| vascular endothelial growth factor A | OKDB#: 30 |
| Symbols: | VEGFA | Species: | human | ||
| Synonyms: | VPF, VEGF, MVCD1 | Locus: | 6p21.1 in Homo sapiens |
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| General Comment |
VEGF is a heparin-binding growth factor specific for vascular endothelial cells that is able to induce angiogenesis in vivo. DNA sequencing suggests the existence of several molecular species of VEGF. VEGFs are secreted proteins, in contrast to other endothelial cell mitogens such as acidic or basic fibroblast growth factors and platelet-derived endothelial cell growth factor (Leung et al., 1989).
NCBI Summary: This gene is a member of the PDGF/VEGF growth factor family. It encodes a heparin-binding protein, which exists as a disulfide-linked homodimer. This growth factor induces proliferation and migration of vascular endothelial cells, and is essential for both physiological and pathological angiogenesis. Disruption of this gene in mice resulted in abnormal embryonic blood vessel formation. This gene is upregulated in many known tumors and its expression is correlated with tumor stage and progression. Elevated levels of this protein are found in patients with POEMS syndrome, also known as Crow-Fukase syndrome. Allelic variants of this gene have been associated with microvascular complications of diabetes 1 (MVCD1) and atherosclerosis. Alternatively spliced transcript variants encoding different isoforms have been described. There is also evidence for alternative translation initiation from upstream non-AUG (CUG) codons resulting in additional isoforms. A recent study showed that a C-terminally extended isoform is produced by use of an alternative in-frame translation termination codon via a stop codon readthrough mechanism, and that this isoform is antiangiogenic. Expression of some isoforms derived from the AUG start codon is regulated by a small upstream open reading frame, which is located within an internal ribosome entry site. The levels of VEGF are increased during infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), thus promoting inflammation by facilitating recruitment of inflammatory cells, and by increasing the level of angiopoietin II (Ang II), one of two products of the SARS-CoV-2 binding target, angiotensin-converting enzyme 2 (ACE2). In turn, Ang II facilitates the elevation of VEGF, thus forming a vicious cycle in the release of inflammatory cytokines. [provided by RefSeq, Jun 2020] |
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| General function | Ligand, Growth factor, Cell death/survival, Cell proliferation | ||||
| Comment | VEGF antagonist for the prevention of ovarian hyperstimulation syndrome: Current status. Naredi N 2014 et al. Ovarian Hyperstimulation Syndrome (OHSS) an iatrogenic and potentially life-threatening complication resulting from an exaggerated response to ovulation induction with gonadotropins during assisted reproductive technologies, is a self-limiting disorder with a broad spectrum of clinical manifestations related to increased capillary permeability and fluid retention brought about by many biochemical mediators especially vascular endothelium growth factor (VEGF), playing a pivotal role in its pathophysiology. Although various strategies had been proposed and tried to prevent this serious complication none was found to be completely effective. With the current knowledge and understanding of the causative molecule i.e. VEGF in the pathogenesis of OHSS, pharmacologic tools targeting this member of the family of heparin binding proteins, seems promising. Antagonizing and blocking VEGF action by dopamine agonists especially Cabergoline has shown to be a valid alternative to overcome the changes induced by the gonadotropins. Delaying embryo transfer with embryo cryopreservation definitely reduces the incidence of OHSS but not the early OHSS. In-vitro maturation of oocytes a major breakthrough in the field of ART although totally eliminates the risk of OHSS is highly labor intensive and cannot routinely carried in all cycles. Thus the newer drugs, mainly the dopamine agonists in the light of the new pathogenic and pharmacological evidence, should definitely be considered for prevention of both early and late OHSS. ///////////////////////// VEGF, a homodimeric glycoprotein of relative molecular mass 45,000, is the only mitogen that specifically acts on endothelial cells. It may be a major regulator of tumor angiogenesis in vivo. Vascular endothelial growth factor (VEGF) production by the monkey corpus luteum during the menstrual cycle: isoform-selective messenger RNA expression in vivo and hypoxia-regulated protein secretion in vitro Tesone M,et al . Experiments were designed to investigate the expression and regulation of vascular endothelial growth factor (VEGF) in the primate corpus luteum (CL) throughout the luteal life span in the natural menstrual cycle. Corpora lutea were collected during the early (ECL; Days 3-5 post-LH surge), mid (MCL; Day 6- 8 post-LH surge), mid-late (MLCL; Days 10-12 post-LH surge), late (LCL; Days 14-16 post-LH surge), and very late (Days 17- 18 post-LH surge) luteal phase. Specific primers were designed to amplify mRNAs encoding VEGF isoforms 206, 189, 183, 165, 145, and 121. Only two cDNA products were obtained by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends; cloning and sequencing confirmed their 98% homology to the corresponding human VEGF 165 and 121 sequences. Semiquantitative RT-PCR assays indicated that VEGF 165 mRNA levels increased (P < 0.05) from ECL to MLCL but then declined (P < 0.05) by LCL. Although VEGF 121 mRNA levels were limited in ECL, they increased significantly in MCL (P < 0.05). Levels of VEGF protein, as measured by Western blot analysis, were two- to fourfold higher for VEGF 165 versus VEGF 121. Also, VEGF 165 levels were higher (P < 0.05) in ECL and MCL compared to those at later stages. During 2-day culture, preparations of dispersed luteal cells secreted VEGF into the media; the highest levels were observed in ECL and declined (P < 0.05) by LCL. Regardless of luteal stage, hypoxic conditions increased (P < 0.05) VEGF levels, whereas LH exposure increased (P < 0.05) progesterone, but not VEGF, in the media. These results are consistent with a dynamic, local regulation of VEGF production during the life span of the primate CL that is not directly controlled by LH. Single-chain bi-functional VEGF-FSH-CTP is superior to the combination therapy of rec-VEGF plus FSH-CTP in stimulating angiogenesis during ovarian folliculogenesis. Trousdale RK et al. Infertility technologies often employ exogenous gonadotropin therapy to increase antral follicle production. In an effort to enhance ovarian response several long-acting FSH therapies have been developed including an FSH-CTP, where the FSH subunits are linked by the C-terminal peptide (CTP) moiety from human chorionic gonadotropin (hCG) which is responsible for the increased half-life of hCG. We found that administration of FSH-CTP for ovarian hyperstimulation in rats blunted ovarian follicle vascular development. In women, reduced ovarian vasculature has been associated with lower pregnancy rates. We were interested in determining if vascular endothelial growth factor (VEGF) therapy could enhance ovarian angiogenesis in FSH-CTP treated rats. Co-administration of systemic FSH-CTP plus recombinant VEGF was compared with treatment with a novel, single-chain bi-functional VEGF-FSH-CTP (VFC) analog. For VFC the FSH portion targets the protein to the ovary and stimulates follicle growth while VEGF enhances local vascular development. Both in vitro and in vivo studies confirm the dual FSH and VEGF action of the VEGF-FSH-CTP protein. Evaluation of ovarian follicle development demonstrates that administration of combination therapy using VEGF and FSH-CTP failed to increase follicle vasculature above levels seen with FSH-CTP monotherapy. However, treatment with VFC significantly increased follicle vascular development while concurrently increasing the number of large antral follicles produced. In conclusion we report the production and characterization of a long-acting, bi-functional VEGF-FSH-CTP protein which is superior to combination therapy for enhancing VEGF activity in the ovary and stimulating follicular angiogenesis in rats. | ||||
| Cellular localization | Secreted | ||||
| Comment | candidate123 | ||||
| Ovarian function |
Follicle endowment, Initiation of primordial follicle growth, Primary follicle growth, Preantral follicle growth, Follicle atresia, Ovulation, Steroid metabolism, Luteinization, Oocyte growth, Early embryo development
, Pluripotent cell derivation |
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| Comment | The FSH-HIF-1α-VEGF pathway is critical for ovulation and oocyte health but not necessary for follicular growth in mice. Li C et al. (2020) Recent evidence has indicated that follicular vascularization is critical to ovarian follicle development and survival. Follicle-stimulating hormone (FSH), a gonadotropin that induces follicular growth and development, also acts as the major survival factor for antral follicles. FSH has been reported to stimulate angiogenesis in the theca layers mediated in part by the vascular endothelial growth factor A (VEGFA) and the transcription factor hypoxia inducible factor 1α (HIF-1α). However, it remains largely undetermined whether FSH-dependent growth and survival of antral follicles relies on FSH-induced vascularization. Here, we first demonstrated that induction of angiogenesis through the FSH-HIF-1α-VEGFA axis is not required for FSH-stimulated follicular growth in mouse ovary. FSH increased the total number of blood vessels in mouse ovarian follicles, which was correlated with elevated expression of VEGFA and HIF-1α in granulosa cells (GCs). In contrast, blocking of follicular angiogenesis using inhibitors against the HIF-1α-VEGFA pathway repressed vasculature formation in follicles despite FSH administration. Interestingly, by measuring follicular size and ovarian weight, we found that the suppression of angiogenesis via HIF-1α-VEGFA pathway did not influence FSH-mediated follicular growth. However, inhibition of FSH-induced follicular vascularization by PX-478, a small-molecule inhibitor that suppresses HIF-1α activity, blocked ovulation and triggered atresia in large follicles. On the other hand, PX-478 injection reduced oocyte quality via impairing the meiotic apparatus, showing a prominently defective spindle assembly and actin dynamics. Collectively, our findings unveiled a vascularization-independent effect of FSH on follicular growth; whereas follicular survival, ovulation, and oocyte development relies on FSH-mediated angiogenesis in the follicles.////////////////// Increased supply from blood vessels promotes the activation of dormant primordial follicles in mouse ovaries. Komatsu K et al. (2020) The controlled activation of dormant primordial follicles is important for the maintenance of periodic ovulation. Previous reports have clearly identified the signaling pathway in granulosa cells and oocytes that controls the activation of primordial follicles; however, the exact cue for the in vivo activation of dormant primordial follicles is yet to be elucidated. In this study, we found that almost all activated primordial follicles made contact with blood vessels. Based on this result, we speculated that the contact between primordial follicles and blood vessels may provide a cue for the activation of dormant primordial follicles. To confirm this hypothesis, we attempted to activate dormant primordial follicles within the ovaries by inducing angiogenesis through the use of biodegradable gels containing recombinant vascular endothelial growth factor and in cultured ovarian tissues by increasing the serum concentration within the culture medium. The activation of dormant primordial follicles was promoted in both experiments, and our results indicated that an increase in the supply of the serum component, from new blood vessels formed via angiogenesis, to the dormant primordial follicles is the cue for their in vivo activation. In the ovaries, angiogenesis often occurs during every estrous cycle, and it is therefore likely that angiogenesis is the crucial event that influences the activation of primordial follicles.////////////////// Intravenous neutralization of vascular endothelial growth factor reduces vascular function/permeability of the ovary and prevents development of OHSS-like symptoms in rhesus monkeys. Bishop CV et al. (2017) Ovarian hyperstimulation syndrome (OHSS) is a disorder associated with elevated serum VEGFA following chorionic gonadotropin (hCG) exposure in controlled ovarian stimulation (COS) cycles in women. In this study, we tested the effect of intravenous VEGFA neutralization on OHSS-like symptoms and vascular function in rhesus macaques during COS cycles. Monkeys (n = 8) were treated with 3 COS protocols and assigned randomly to groups as follows: 1) COS alone (Control, n = 5); 2) COS + VEGF mAb Avastin 19 ± 5 h before hCG (Avastin pre-hCG; n = 6); 3) COS + Avastin 3-4 days post-hCG (Avastin post-hCG; n = 4); 4) COS + Simulated Early Pregnancy (SEP n = 3); or 5) COS + SEP + Avastin (SEP + Avastin n = 3). Follicles were aspirated 36 h post-hCG, fluid was collected from one follicle for analysis of steroid and vascular hormone content. Remaining follicles were aspirated, and luteinized granulosa cells (LGCs) cultured for 24 h. Ovarian/uterine vascular flow (VF) and blood volume (BV) were analyzed by contrast enhanced ultrasound (CEUS) before hCG bolus and 6-8 days post-hCG bolus/time of peak SEP response. Ovarian permeability to albumin was analyzed by Dynamic Contrast Enhanced-MRI (DCE-MRI) post-hCG. Abdominal fluid was present in 4/5 Control, 2/6 Avastin pre-hCG, and 3/4 Avastin post-hCG females. Neutralization of VEGFA before hCG reduced ovarian VF, BV, and permeability to albumin (P < 0.05), while only ovarian VF and permeability were reduced in Avastin-post hCG group (P < 0.05). There was no effect of Avastin on ovarian vascular function during COS + SEP. VEGF levels in follicular fluid were reduced 78-fold by Avastin pre-hCG, and LGCs exposed to Avastin in vivo also released 4-fold less VEGF into culture media (P < 0.05). Culture medium of LGCs exposed to VEGFA neutralization in vivo had lower levels of P4 and ANGPT1, and an increased ratio of ANGPT2/1 (P < 0.05). Uterine VF was reduced by SEP + Avastin in the basalis/junctional zone (P < 0.05). Avastin treatment before hCG prevents the development of symptoms associated with ovarian hyperstimulation syndrome. In vitro data suggest neutralization of VEGFA alters expression of other vascular factors typically induced by hCG in the luteinizing follicle. Neutralization of VEGFA action alters the vascular function of the basalis zone of the uterus during simulated early pregnancy, indicating a potential effect on embryo implantation.////////////////// Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA) synergistically promote steroidogenesis and survival of cultured buffalo granulosa cells. Mishra SR et al. (2017) The present study investigated the combined effect of fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGF-A) on estradiol (E2) secretion and relative abundance of mRNA for aromatase enzyme (CYP19A1), proliferating cell nuclear antigen (PCNA) and BCL-2 associated X protein (BAX) in cultured buffalo granulosa cells (GCs). Follicles were isolated and classified into four groups based on size and E2 concentration in follicular fluid (FF): Small, 4-6mm diameter, E2<0.5ng/ml; Medium, 7-9mm, E2=0.5-5ng/ml; Large, 10-13mm, E2=5-40ng/ml; Preovulatory (PFs), >14mm, E2>180ng/ml. The GCs of PF were cultured in 24 well cell culture plates and allowed to become 75-80% confluent. Then cultured GCs were treated with FGF2 (200ng/ml) and VEGF-A (100ng/ml) separately and in combination for three incubation periods (24, 48 and 72h). Estradiol secretion was greater in GCs treated with FGF2+VEGF-A compared to FGF2 or VEGF-A at all incubation periods and was greatest (P<0.05) at 72h of incubation. The relative abundance of CYP19A1 and PCNA mRNA were relatively consistent with the amount E2 secretion. In contrast, the relative abundance of Bax mRNA was less in GCs treated with the combination of FGF2 and VEGF-A as compared to either FGF2 or VEGF-A alone and the least concentration (P<0.05) was at 72h of incubation. Findings with use of immunocytochemistry of cells treated with these factors were consistent to the relative abundance of mRNA transcript for the factor. The present findings indicate that FGF2 and VEGF-A may function in a synergistic manner to promote steroidogenesis and survival of cultured buffalo GCs.////////////////// Effect of Local Basic Fibroblast Growth Factor and Vascular Endothelial Growth Factor on Subcutaneously Allotransplanted Ovarian Tissue in Ovariectomized Mice. Gao J et al. (2015) One of the major obstacles to ovarian tissue preservation is delayed angiogenesis that leads follicles lost after transplantation. The aim of the present study was to investigate the effects of bFGF and VEGF on heterotopic transplanted ovarian tissue using a mouse model. Female mice underwent bilateral ovariectomy. Ovarian tissues encapsulated by fibrin hydrogels were transplanted subcutaneously into recipient mice, in which ovarian hormonal cyclicity was absent. The fibrinogen solution was mixed with bFGF, VEGF, or a mixture of bFGF and VEGF. The grafts were recovered 21 days after transplantation. Follicle morphology and follicle numbers were observed by H&E staining. Blood vessels were observed in transplanted intra-ovarian tissue by CD31 antibody IHC staining. Daily vaginal cytology was performed to determine estrous cycle and functional restoration of transplanted ovarian tissue. Blood was collected weekly and serum FSH levels were measured with a radioimmunoassay kit. Apoptosis analysis was performed by anti-AC-3 staining and survivin mRNA expression. The number of primordial follicles and secondary follicles in the bFGF+VEGF group was significantly higher than in the control group. The vascular density in the bFGF+VEGF groups were significantly higher than in the bFGF and the VEGF groups; there was no significant difference between the bFGF and VEGF groups. Estrous cycle was earlier in the bFGF+VEGF group compared with the control group; all mice in this group restored ovarian function. Serum FSH levels in the bFGF+VEGF group were significantly lower than in the control group by day 14 post-transplantation. The AC-3-positive in control group was significantly higher compared with bFGF group and VEGF group, and in bFGF+VEGF group was significantly lower than bFGF group and VEGF group. Survivin mRNA expression in bFGF+VEGF group was significantly higher than control group. The combination of bFGF and VEGF has beneficial effects on follicle survival, angiogenesis, and resumption of estrous cycles.////////////////// Vascular endothelial growth factor A improves quality of matured porcine oocytes and developing parthenotes. Kere M 2014 et al. Vascular endothelial growth factor is a multipotent angiogenic factor implicated in cell survival and proliferation. The objective was to determine effects of exogenous recombinant human VEGFA (or VEGFA165) in culture media on porcine oocyte maturation and parthenote development. Adding 5ng/mL VEGFA to the culture medium improved the maturation rate of denuded oocytes (P < 0.05), although 5, 50, or 500ng/mL did not significantly affect nuclear maturation of oocytes. Parthenotes from oocytes cultured either in invitro maturation or invitro culture medium supplemented with 5 or 50ng/mL VEGFA had an improved blastocyst rate and increased total numbers of cells (P < 0.05). Moreover, those treated with 5ng/mL of VEGFA had a higher hatched blastocyst rate (average of 121 cells per blastocyst). All VEGFA-treated oocytes had reduced apoptotic indices (P < 0.05), except for those with a higher dose (500ng/mL) of VEGFA which had more apoptotic cells (P < 0.05). Adding 5ng/mL VEGFA to oocytes during the last 22h of invitro maturation improved (P < 0.05) blastocyst rates and total numbers of cells, with reduced apoptosis indices similar to that of long-term (44h) culture. Furthermore, Axitinib (VEGFR inhibitor) reversed the effects of VEGFA on parthenote development (P < 0.05). Follicular fluids from medium (2-6mm) to large (>6mm) follicles contained 5.3 and 7.0ng/mL vascular endothelial growth factor protein, respectively, higher (P < 0.05) than concentrations in small (<2mm) follicles (0.4ng/mL). Also, VEGFA and its receptor (VEGFR-2) were detected (immunohistochemistry) in growing follicles and developing blastocysts. In addition, VEGFA inhibited caspase-3 activation in matured oocytes (P < 0.05). In conclusion, this is apparently the first report that VEGFA has proliferative and cytoprotective roles in maturing porcine oocytes and parthenotes. Furthermore, an optimal VEGFA concentration promoted porcine oocyte maturation and subsequent development. ///////////////////////// Expression Pattern of Vascular Endothelial Growth Factor in Canine Folliculogenesis and its Effect on the Growth and Development of Follicles after Ovarian Organ Culture. Abdel-Ghani M 2014 et al. In this study, the expressions of VEGF in dog follicles were detected by immunohistochemistry and the effects of VEGF treatment on the primordial to primary follicle transition and on subsequent follicle progression were examined using a dog ovary organ culture system. The frozen-thawed canine ovarian follicles within slices of ovarian cortical tissue were cultured for 7 and 14?days in presence or absence of VEGF. After culture, the ovaries were fixed, sectioned, stained and counted for morphologic analysis. The results showed that VEGF was expressed in the theca cells of antral follicles and in the granulosa cells nearest the oocyte in preantral follicle but not in granulosa cells of primordial and primary follicles; however, the VEGF protein was expressed in CL. After in vitro culture, VEGF caused a decrease in the number of primordial follicles and concomitant increase in the number of primary follicles that showed growth initiation and reached the secondary and preantral stages of development after 7 and 14?days. Follicular viability was also improved in the presence of VEGF after 7 and 14?days in culture. In conclusion, treatment with VEGF was found to promote the activation of primordial follicle development that could provide an alternative approach to stimulate early follicle development in dogs. ///////////////////////// Stimulatory effect of vascular endothelial growth factor on progesterone production and survivability of cultured bubaline luteal cells. Chouhan VS 2014 et al. The objectives of the present study were to investigate the effects of vascular endothelial growth factor (VEGF) on progesterone (P4) synthesis in cultured luteal cells from different stages of the estrous cycle and on expression of steroidogenic acute regulatory protein (STARD1), cytochrome P450 cholesterol side chain cleavage (CYP11A1) and 3?hydroxysteroid dehydrogenase (HSD3B), antiapoptotic gene PCNA, and proapoptotic gene BAX in luteal cells obtained from mid-luteal phase (MLP) of estrous cycle in buffalo. Corpus luteum samples from the early luteal phase (ELP; day 1st-4th; n=4), MLP (day 5th-10th; n=4), and the late luteal phase (LLP; day 11th-16th; n=4) of oestrous cycle were obtained from a slaughterhouse. Luteal cell cultures were treated with VEGF (0, 1, 10 and 100ng/ml) for 24, 48 and 72h. Progesterone was assessed by RIA, while mRNA expression was determined by quantitative real-time PCR (qRT-PCR). Results indicated a dose- and time-dependent stimulatory effect of VEGF on P4 synthesis and expression of steroidogenic enzymes. Moreover, VEGF treatment led to an increase in PCNA expression and decrease in BAX expression. In summary, these findings suggest that VEGF acts locally in the bubaline CL to modulate steroid hormone synthesis and cell survivability, which indicates that this factor has an important role as a regulator of CL development and function in buffalo. ///////////////////////// Role of Vascular Endothelial Growth Factor in Maintenance of Pregnancy in Mice. Wada Y et al. It is well known that withdrawal of progesterone from the maternal circulation is a critical stimulus to parturition in rodents, such as rats and mice. However, mechanisms that determine the timing of progesterone withdrawal are not completely understood. In the present study, we examined whether the vascular endothelial growth factor (VEGF) system in the corpus luteum (CL) contributes to the regulation of circulating progesterone levels and acts as a determinant of the timing of parturition in mice. We found that reduction in the expression levels of VEGF and VEGF receptor-2 in the CL precedes the impairment of luteal circulation and a series of events leading to parturition (i.e., reduction of plasma progesterone, enhancement of myometrium contractility, and onset of parturition). Blocking of VEGF signaling by using the inhibitor of VEGFR tyrosine kinase KRN633 at mid-pregnancy caused a similar sequence of events and induced preterm birth. These results suggest that the VEGF system in the CL plays a critical role in maintaining a high level of circulating progesterone, and determining the timing of parturition in mice. Vascular endothelial growth factor-A(165) (VEGF-A (165)) stimulates the in vitro development and oocyte competence of goat preantral follicles. Ara?R et al. The aim of this study was to evaluate the effect of vascular endothelial growth factor-A(165) (VEGF-A(165)) on the in vitro development of goat secondary preantral follicles. Preantral follicles (=150??m in diameter) were isolated from the ovaries of adult mixed-breed goats and individually cultured for 18?days in aMEM in the absence (control) or presence of VEGF-A(165) at concentrations of 10?ng/ml (VEGF10) and 100?ng/ml (VEGF100). Analyses of follicular survival, diameter, antrum formation and rate of daily growth were performed every 6?days. At the end of the culture period, morphologically normal oocytes (=110??m in diameter) were taken for in vitro maturation (IVM). The results demonstrated that all follicles presented oocytes and granulosa cells that were morphologically normal and after labeling with calcein-AM, high rates of oocyte viability were observed in all treatments. The follicular diameter and the growth rate achieved in the presence of VEGF10 were higher than those of the control. Both treatments with VEGF-A(165) showed higher rates of oocyte recovery for IVM when compared with the control. Moreover, only the addition of VEGF-A(165) permitted oocytes grown in vitro to reach metaphase II. Thus, the addition of VEGF-A(165) to the culture medium improves the development of goat preantral follicles cultured in vitro, allowing the production of mature oocytes. Ovulation is accompanied by a large increase in the permeability of the capillaries surrounding the follicle, beginning a few hours after the ovulatory stimulus. The resulting edema may play a role in ovulation as well as in the formation and vascularization of the CL. Koos (1995) reported a marked increase in steady state levels of the transcripts for VEGF120 and VEGF164 between 1 and 4 h after hCG in whole ovaries of PMSG-primed immature rats. Increases were detectable both in granulosa cells and in thecal/stromal tissue. The high level of expression was maintained in the corpus luteum. Thus, the preovulatory increase in follicular vascular permeability is closely associated with a marked, sustained increase in VEGF expression. Ferrara et al. (1996) reported that treatment with truncated soluble Flt-1 receptors, which inhibit VEGF bioactivity, resulted in complete suppression of CL angiogenesis in a rat model of hormonally induced ovulation. This effect was associated with inhibition of CL development and progesterone release. These findings demonstrate that, in spite of the redundancy of potential mediators, VEGF is essential for CL angiogenesis. Fraser HM, et al 2000 reported the suppression of luteal angiogenesis in the primate after neutralization of vascular endothelial growth factor Marmosets were treated with an antibody to vascular endothelial growth factor (VEGF). Treatment commenced at the time of ovulation and was continued for 3 days (early luteal group) or 10 days (midluteal group). Bromodeoxyuridine was used to label proliferating cells, being administered 1 h before collecting ovaries from control and treated animals in the early or midluteal phase. Intense proliferation in the early luteal phase was suppressed by anti-VEGF treatment. This resulted in blockade of development of the normally extensive capillary bed, as in the animals treated until the mid-luteal phase the numbers of endothelial cells were reduced. The hormone-producing cells remained largely unaltered in the posttreatment corpus luteum, although the presence of lipid accumulation, and small pockets of cells showing basophilia and nuclear condensation were observed. Significantly, luteal function, as judged by secretion of progesterone, was markedly compromised by the treatment, being reduced by 60% in comparison with controls. Danforth DR, et al reported that Vascular Endothelial Growth Factor Stimulates Preantral Follicular Growth in the Rat Ovary. The regulation of preantral follicle growth in mammals is poorly understood. The availability of an adequate vascular supply to provide endocrine and paracrine signals may be important in the early states of follicle growth as well as the later states of follicle selection and dominance. The objective of the present study was to investigate whether Vascular Endothelial Growth Factor (VEGF) plays a role in preantral follicle development in the rat ovary. Immature (21 day old) Sprague Dawley rats were injected with 500 ng VEGF in saline or 50 micro g diethylstilbestrol (DES) in oil under the bursa of one ovary. The contralateral ovary was injected with a corresponding volume of vehicle. Rats were euthanitized 48h later and the ovaries were removed and analyzed histologically. Intrabursal administration of VEGF significantly increased the number of primary and small secondary, but not large secondary preantral follicles in the ovary, similar to the effect of DES (p<0.05). VEGF stimulated preantral follicle growth in a time- and dose-dependent manner. Subcutaneous DES administration increased the number of primary and secondary follicles, and both subcutaneous and intrabursal estrogen administration stimulated VEGF protein expression in the rat ovary. These data indicate that VEGF stimulates preantral follicle development in the rat ovary, is regulated by estrogen, and may be one of the factors that participate in the regulation of early follicle growth in the rat. Direct injection of vascular endothelial growth factor into the ovary of mice promotes follicular development. Fertil Steril. 2004 . Fraser HM,et al reported that single Injections of Vascular Endothelial Growth Factor Trap Block Ovulation in the Macaque and Produce a Prolonged, Dose-Related Suppression of Ovarian Function. Follicular development is associated with intense angiogenesis and increased permeability of blood vessels under the control of locally-produced angiogenic factors such as vascular endothelial growth factor (VEGF). The aim of the present study was to evaluate the effects of transient inhibition of VEGF on pituitary-ovarian function in the macaque. Animals were given a single, intravenous injection of a potent, receptor-based VEGF antagonist, the VEGF Trap. VEGF Trap was given at a dose of 4, 1 or 0.25 mg/kg in the mid-follicular phase or at 1.0 mg/kg in the late follicular phase. Controls were treated with vehicle or a control protein, recombinant human Fc (1 mg/kg). Blood samples were collected once daily for 12 days following injection, and three times per week thereafter until normal ovulatory cycles had resumed. The VEGF Trap produced a rapid suppression of estradiol and inhibin B concentrations at all doses tested, followed by a marked and sustained increase in LH and FSH. Ovulation and formation of a functional corpus luteum, as evidenced by increased serum progesterone levels, failed to occur at the anticipated time. Normal ovarian activity resumed when plasma concentrations of unbound VEGF Trap fell below about 1 mg/L. When treatment was initiated in the mid-follicular phase, control macaques ovulated 7.2 +/- 0.4 days later, but ovulation was delayed in a dose dependent manner by VEGF Trap, occurring 23 +/- 0.7, 30 +/- 1.4 and 43 +/- 0.8 days after injection of 0.25, 1 or 4 mg/kg respectively. Thus, the VEGF Trap exerts a potent, dose-dependent but reversible inhibitory effect on ovarian function. Expression of vascular endothelial growth factor messenger ribonucleic acid and protein in human preimplantation embryos. Hwu YM et al. In contrast to a previous report by Krussel et al., with the inclusion of larger numbers of unfertilized oocytes and normal embryos and more sensitive immunofluorescence, this study shows that expression of vascular endothelial growth factor messenger ribonucleic acid can be detected from the oocyte to the blastocyst stage and that protein can be detected from the 3-cell stage to the blastocyst stage in human preimplantation embryos. Neutralization of Endogenous Vascular Endothelial Growth Factor Depletes Primordial Follicles in the Mouse Ovary. Roberts AE et al. The regulation of early follicular growth and development involves a complex interaction of autocrine, paracrine, and endocrine signals. The ability of these factors to regulate follicle growth may depend, in part, on the extent of vascular delivery to and perfusion of the ovary. Vascular endothelial growth factor A (VEGFA) is a major regulator of vascular physiology in the ovary. VEGFA is produced in numerous ovarian compartments, and likely plays a role in the regulation of all phases of follicular growth from preantral through preovulatory. The aim of the present study was to further evaluate the role of VEGF in early follicle growth by neutralization of endogenous VEGF or VEGF receptors. Adult mice were injected systemically or prepubertal mice were injected directly under the ovarian bursa with antibodies designed to neutralize VEGF or block interaction with its receptors in the ovary. Both systemic and intrabursal injections of VEGF antibody significantly reduced the number of primordial follicles within 1-3 days after administration without affecting primary or secondary follicle numbers. Primordial follicle numbers were not different from control levels by 30 days after VEGFA antibody administration. Administration of antibodies to the kinase domain receptor (KDR) for VEGF but not the FMS-like tyrosine receptor (FLT1) for VEGF also results in a significant decrease in primordial follicles. These data suggest that VEGF plays a vital role in the maintenance and growth of the primordial follicle pool. Vascular endothelial growth factor (VEGF) suppresses ovarian granulosa cell apoptosis in vitro. Kosaka N et al. Vascular endothelial growth factor (VEGF) inhibits the follicular atresia that resulted from granulosa cell apoptosis in the mammalian ovary. In the present study, we examined the effect of VEGF on granulosa cell apoptosis. Here, we report that VEGF suppresses granulosa cell apoptosis by inhibiting the release of caspase-activated DNase (CAD) without being associated with the mitochondrial pathway. VEGF did not stimulate or inhibit Bcl-xL and Bax, respectively, in granulosa cells. In addition, VEGF did not suppress the expression of active caspase-3, whereas follicle-stimulating hormone (FSH) inhibited caspase-3. However, VEGF and FSH suppressed the release of CAD resulting from the disintegration of the CAD-ICAD complex. These results demonstrate that VEGF is a strong survival factor for granulosa cell apoptosis (ovarian follicular atresia). Effect of direct ovarian injection of vascular endothelial growth factor gene fragments on follicular development in immature female rats. Shimizu T et al. Vascular endothelial growth factor (VEGF) expression in granulosa cells is associated with the thecal vasculature growth during ovarian follicular development. We hypothesized that injection of VEGF gene fragments directly into the rat ovary would induce production of a large number of ovulatory follicles and that these follicles would ovulate. To test this hypothesis, we treated immature female rats with combinations of hormones and VEGF gene fragments. The animals were divided into two groups: one group received solution containing transfection reagents as a control (n = 5), while the other group received direct ovarian injection of VEGF gene fragments at 19 (n = 5), 21 (n = 5), 23 (n = 5), or 25 (n = 5) days after birth followed by i.p. administration of 20 IU equine chorionic gonadotropin (eCG) at the age of 26 days. Forty-eight hours after eCG injection, animals were given 20 IU human chorionic gonadotropin (hCG) i.p. and then the oocytes in both groups were counted. The maximum number of ovulated oocytes was obtained when the VEGF gene fragments were injected into the rat ovary at 21 days after birth. Histological examination revealed that the injection of VEGF gene fragments markedly increased the vascular density around the preovulatory follicles and also the number of these follicles. Our data provide the first reported evidence that most ovulatory follicles generated by injection of VEGF gene fragments are able to ovulate upon hCG treatment. These results demonstrate that injection of VEGF gene fragments directly into the ovary stimulates the development of antral follicles by inducing the formation of thecal vasculature in immature female rats. Follicular fluid VEGF levels directly correlate with perifollicular blood flow in normoresponder patients undergoing IVF. Monteleone P et al. BACKGROUND: It has become increasingly clear that the follicular microenvironment of the maturing human oocyte is a determining factor for the implantation potential of an embryo deriving from that oocyte. Indeed the quality and maturity of an oocyte are influenced by the level of intrafollicular oxygen content which, in turn, is proportional to the degree of follicular vascularity. The aim of the study was to establish whether there is a relationship between follicular fluid VEGF concentrations, perifollicular vascularity and reproductive outcome in normal responders under the age of 35 undergoing IVF. MATERIALS AND METHODS: Sixty-one consecutive patients, all at their first IVF cycle, were included in the study. All patients had primary infertility due to male factor or tubal factor. At oocyte retrieval, the perifollicular vascularity of two follicles per ovary was estimated qualitatively through power Doppler blood flow, for a total of two hundred forty-four follicles. The follicular fluid from the identified follicles was centrifuged and stored until VEGF assay. The maturity and fertilization rate of the corresponding oocytes as well as embryo quality and pregnancy rate were recorded. RESULTS: In our study, we found VEGF levels to be significantly correlated with grade of perifollicular vascularity. Oocytes obtained from follicles with the higher grade of vascularization also showed a higher rate of fertilization, embryos, a better quality and higher pregnancy rates were obtained in women with highly vascularized follicles. Perifollicular blood flow doppler indices seem to predict oocyte viability and quality. Moreover, VEGF may play a potential role in the development of the perifollicular capillary network. DISCUSSION: The ability of a given follicle to express VEGF and develop an adequate vascular network may be inter-related in patients under the age of 35. An adequate blood supply may be fundamental important in the regulation of intrafollicular oxygen levels and the determination of oocyte quality. Intrabursal injection of vascular endothelial growth factor trap in eCG-treated prepubertal rats inhibits proliferation and increases apoptosis of follicular cells involving the PI3K/AKT signaling pathway. Abramovich D et al. OBJECTIVE: To investigate the effects of local inhibition of vascular endothelial growth factor A (VEGFA) on proliferation and apoptosis of follicular cells in rat ovaries. To analyze the role of the PI3K/AKT signaling pathway on VEGFA effects. DESIGN: Experimental study. SETTING: Research laboratory. ANIMAL(S): Female Sprague Dawley rats, 21 days old, treated with equine chorionic gonadotropin (eCG). MAIN OUTCOME MEASURE(S): Follicular cell proliferation, apoptosis, and activation of the PI3K/AKT signaling pathway after intrabursal injection of a VEGFA inhibitor. RESULT(S): Inhibition of VEGFA leads to a decrease in the expression of the proliferation marker proliferating cell nuclear antigen (PCNA) in theca and granulosa cells (GC) and an increase in the activation of caspase 3 in antral follicles. Furthermore, we observed a decrease in the phosphorylation of RAC-alpha serine/threonine-protein kinase (AKT) and its target Bcl2 antagonist of cell death (BAD). No differences were found in the levels of kinase insert domain receptor (KDR) protein or in endothelial cell density. CONCLUSION(S): The VEGFA prevents apoptosis and stimulates proliferation of follicular cells, regulating follicular growth and development. The PI3K/AKT signaling pathway is one of the pathways involved in this mechanism. Therefore, VEGFA has a role as an antiapoptotic and proliferative factor in follicular cells from the rat ovary. Neutralization of Vascular Endothelial Growth Factor Antiangiogenic Isoforms Is More Effective Than Treatment with Proangiogenic Isoforms in Stimulating Vascular Development and Follicle Progression in the Perinatal Rat Ovary. Artac RA et al. Inhibition of vascular endothelial growth factor A (VEGFA) signal transduction arrests both vascular and follicle development. Since anti-angiogenic VEGFA isoforms are proposed to block pro-angiogenic VEGFA isoforms from binding to their receptors, we hypothesized that pro-angiogenic isoforms promote and anti-angiogenic isoforms inhibit these processes. The anti-angiogenic isoforms, Vegfa_165b and 189b, were amplified and sequenced from rat ovaries. The 165b sequence was 90% homologous to human VEGFA_165B. Quantitative RT-PCR determined Vegfa_165b mRNA was more abundant around Embryonic Day 18 but Vegfa_189b lacked a distinct pattern of abundance. Anti-angiogenic VEGFA isoforms were localized to pre-granulosa and granulosa cells of all follicle stages and to theca cells of advanced stage follicles. To determine the effects of VEGFA isoforms in developing ovaries, Postnatal Day 3/4 rat ovaries were cultured with VEGFA164 or an antibody to anti-angiogenic isoforms (anti-VEGFAxxxB). Treatment with 50 ng/ml of VEGFA164 resulted in a 93% increase in vascular density (P < 0.01) and treated ovaries were composed of fewer primordial follicles (stage 0) and more developing follicles (stages 1-4) than controls (P < 0.04). Ovaries treated with 5 ng/ml of VEGFAxxxB antibody had a 93% increase in vascular density (P < 0.02) with fewer primordial and early primary follicles (stage 1) and more primary, transitional, and secondary follicles (stages 1, 3, and 4, respectively) compared to controls (P < 0.005). We conclude that neutralization of anti-angiogenic VEGFA isoforms may be a more effective mechanism of enhancing vascular and follicular development in perinatal rat ovaries than treatment with the pro-angiogenic isoform, VEGFA164. Direct Survival Role of Vascular Endothelial Growth Factor (VEGF) on Rat Ovarian Follicular Cells. Irusta G et al. The aim of the present work was to analyze the direct effect of VEGF in follicular cell proliferation, apoptosis and activation of the PI3K/AKT and ERK/MEK signaling pathways in early antral follicles or granulosa cells. Antral follicles or granulosa cells were isolated from prepubertal female Sprague Dawley rats treated with DES.VEGF directly stimulates follicular cell proliferation and it also decreases apoptosis by inhibiting caspase 3 activation. In addition, VEGF increases the proliferation and inhibits the apoptosis of isolated granulosa cells in culture. VEGF activates the PI3K/AKT pathway evidenced by an increase in AKT phosphorylation levels and induces the phosphorylation of ERK1/2 in cultured antral follicles. These results demonstrate for the first time that VEGF has a proliferative and cytoprotective role in early antral follicles and in granulosa cells isolated from DES treated- prepubertal rats and suggest that PI3K/AKT and ERK/MEK signaling pathways are involved in these processes. Expression of vascular endothelial growth factor A during ligand-induced down-regulation of luteinizing hormone receptor in the ovary. Harada M et al. Vascular endothelial growth factor A (VEGF-A) is one of the most important regulators of ovarian angiogenesis. In this study, we examined the temporal relationship between VEGF-A and luteinizing hormone receptor (LHR) mRNA expression during ligand-induced down-regulation of LHR. Immature female rats were treated with pregnant mare's serum gonadotropin followed by 25 IU hCG 56h later (day 0). On day 5, treatment with hCG (50IU) to down-regulate LHR showed a temporal decrease in VEGF-A mRNA and protein levels in parallel with decreasing LHR mRNA. This effect was specific since the expression of CYP11A1 mRNA showed no decline. Examination of VEGF-A mRNA expression, using in situ hybridization histochemistry with (35)S-labeled antisense VEGF-A mRNA probe, showed intense signal in the corpora lutea on day 5. Treatment with 50IU hCG to down-regulate LHR mRNA showed a decline in the intensity of VEGF-A mRNA in the corpora lutea. VEGF-A mRNA expression returned to control level 53h later when the expression of LHR mRNA also recovered. These results show that the transient down-regulation of VEGF-A mRNA and protein closely parallels the ligand-induced down-regulation of LHR mRNA. The present study establishes a close association between VEGF-A and LHR mRNA expression, suggesting the possibility that VEGF-A-induced vascularization of the ovary is dictated by the expression of LHR and this might play a regulatory role in ovarian physiology. Vascular endothelial growth factor isoforms 120, 164 and 205 are reduced with atresia in ovarian follicles of sheep. Rosales-Torres AM et al. Vascular endothelial growth factor (VEGF) is a potent stimulator of endothelial cell proliferation and neo-vasculogenesis. In the ovary, VEGF mRNA is localised in the follicle, and it is associated with follicular growth and dominance. Alternative splicing of VEGF mRNA produces eight mature forms of mRNA for equal number of VEGF isoforms. In the present study, the VEGF isoforms in granulosa and theca cells of large (4-6mm) and preovulatory (>6mm) sheep follicles were studied during the process of atresia. Follicles were classified as healthy, early atretic and atretic, and the granulosa and theca cells were isolated. The mRNA for three of these isoforms was found in both theca and granulosa cells, and was quantified by image analysis after RT-PCR using primers that amplified VEGF120, VEGF164, VEGF188 and VEGF205 isoforms. The mRNA for these three isoforms was found in both theca and granulosa cells of healthy and atretic follicles. Atresia was accompanied with a reduction in mRNA for VEGF164 and VEGF120 in granulosa and theca cells (P<0.05). Amounts of both isoforms were reduced with the extent of atresia in the granulosa cells, whilst in the theca cells this reduction was only evident in advanced atretic follicles. Furthermore, after the onset of atresia, VEGF205 was not detectable in the granulosa cells. Follicle size did not affect the amount of VEGF mRNA. Hence, the onset of atresia in follicles of sheep is coupled with a reduction in VEGF mRNA. The decrease in VEGF observed with atresia in follicles of sheep was greater in granulosa than in theca cells. | ||||
| Expression regulated by | FSH, LH, Steroids, Growth Factors/ cytokines, IL-1, EGF,FGF, NGF, dopamine, melatoninGDF9, TGFb | ||||
| Comment | Melatonin stimulates VEGF expression in human granulosa-lutein cells: A potential mechanism for the pathogenesis of ovarian hyperstimulation syndrome. Li Y et al. (2020) Melatonin can be synthesized and secreted not only by the pineal gland but also by many extra-pineal tissues. It has been shown that many ovarian functions are regulated by melatonin locally. Ovarian hyperstimulation syndrome (OHSS) is a serious complication during ovulation induction of the in vitro fertilization treatment. To date, the etiology of OHSS is not fully understood. However, vascular endothelial growth factor (VEGF) is recognized as a critical mediator for the pathogenesis of OHSS. High expression of melatonin has been detected in the follicular fluid of OHSS patients. However, whether VEGF expression can be regulated by melatonin in human granulosa cells and further contributes to the pathogenesis of OHSS remain unknown. In this study, we show that melatonin stimulates VEGF expression in human granulosa-lutein (hGL) cells. Our results reveal that the MT2 receptor and activation of AKT are involved in melatonin-induced VEGF expression. Using a rat OHSS model, we report that the VEGF levels are up-regulated in the ovaries of OHSS rats. Blocking the melatonin system by administrating MT2 receptor antagonist, 4-P-PDOT, alleviates OHSS symptoms by decreasing the expression of VEGF. In addition, the expression levels of melatonin and VEGF in the follicular fluid of OHSS patients are up-regulated and positively correlated. This study demonstrates an important role for melatonin in regulating the pathogenesis of OHSS.//////////////////-β1 induces VEGF expression in human granulosa-lutein cells: a potential mechanism for the pathogenesis of ovarian hyperstimulation syndrome. Fang L et al. (2020) Ovarian hyperstimulation syndrome (OHSS) is one of the most serious and iatrogenic complications that can occur during in vitro fertilization treatment. Although the pathogenesis of OHSS is not fully understood, vascular endothelial growth factor (VEGF) has been recognized as an important mediator of the development of OHSS. Transforming growth factor-beta-1 (TGF-β1) is known to regulate various ovarian functions. However, whether VEGF can be regulated by TGF-β1 in human granulosa cells has not been determined. In addition, the role of TGF-β1 in the pathogenesis of OHSS remains unknown. In the present study, we demonstrate that TGF-β1 stimulates VEGF expression in and secretion from both immortalized human granulosa-lutein (hGL) cells and primary hGL cells. Our results demonstrate that the SMAD2/3, ERK1/2, and p38 MAPK signaling pathways are involved in TGF-β1-induced VEGF expression and secretion. Using a mouse OHSS model, we show that the expression levels of TGF-β1 and VEGF are increased in the ovaries of OHSS mice. Blocking TGF-β1 signaling inhibits the development of OHSS by attenuating VEGF expression. Moreover, clinical results reveal that the protein levels of TGF-β1 and VEGF are increased in the follicular fluid of patients with OHSS, and that the levels of these two proteins in the follicular fluid are positively correlated. The results of this study help to elucidate the mechanisms by which VEGF expression is regulated in hGL cells, which could lead to the development of alternative therapeutic approaches for treating OHSS.////////////////// Growth differentiation factor 9 inhibits vascular endothelial growth factor expression in human granulosa cells. Guo C et al. (2020) In aortic endothelial cells, the TGFβ signaling pathway is involved in the regulation of vascular endothelial growth factor (VEGF), which encodes a potent angiogenic factor crucial for the development of ovarian hyperstimulation syndrome. Growth differentiation factor 9 (GDF9) is a member of the TGFβ family and its effect on VEGF expression in human granulosa cells is unknown. In this study, human granulosa cells were collected from patients during the course of oocyte retrieval for in vitro fertilization and were cultured in vitro. After the first 48 h of culture, cells were treated with GDF9 with or without SB431542 (an ALK5 inhibitor) at various doses. The medium was then collected to determine the concentration of VEGF by ELISA. Cellular RNA was collected and extracted for quantification by real-time quantitative fluorescence PCR. Our study showed that GDF9 suppressed VEGF release from human granulosa cells in a dose-dependent manner and also downregulated VEGF mRNA levels in these cells. Furthermore, SB431542 antagonized the suppression of VEGF mRNA by GDF9 and diminished the inhibitory effect of GDF9 on VEGF release by human granulosa cells. Our results indicated that GDF9 can inhibit VEGF expression in human granulosa cells and ALK5 might mediate this process.////////////////// Up-regulation of AREG, EGFR and HER2 contributes to increased VEGF expression in granulosa cells of patients with OHSS†. Fang L et al. (2019) Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication in women undergoing induction of ovulation with human chorionic gonadotropin (hCG) for assisted reproductive techniques. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) ligand expressed in human granulosa cells and follicular fluid and can be up-regulated by luteinizing hormone (LH)/hCG. However, whether the expression levels of AREG, EGFR and HER2 change in the granulosa cells of OHSS patients remains unknown. If it does, whether these molecules are involved in the development of OHSS requires investigation. In the present study, we showed that AREG, EGFR, and HER2 transcripts in granulosa cells as well as follicular fluid AREG proteins were elevated in OHSS patients. Increased AREG levels were associated with transcript levels and follicular content of vascular endothelial growth factor (VEGF), the marker for OHSS pathology. Treatment of cultured granulosa cells with AREG stimulated VEGF expression and secretion, with granulosa cells from OHSS patients showing more rapid and pronounced increases than the non-OHSS group. In addition, siRNA-mediated knockdown of EGFR and AREG attenuated the hCG-induced up-regulation of VEGF. This study demonstrated that granulosa cell-secreted AREG plays an important role in the development of OHSS, suggesting that the EGFR/HER2-mediated signaling could be a novel drug target for the prevention and treatment of OHSS.////////////////// Hormonal regulation of vascular endothelial growth factor A (VEGFA) gene expression in granulosa and theca cells of cattle1. Nichols JA et al. (2019) Vascular endothelial growth factor A (VEGFA) stimulates angiogenesis and is associated with increased vascularity in ovarian follicles of cattle. The objectives of this study were to investigate the developmental and hormonal regulation of VEGFA expression in ovarian granulosa and theca cells of cattle. Bovine ovaries were collected from a local slaughterhouse and granulosa (GC) and theca cells (TC) were collected from small (SM; 1 to 5 mm) and large (LG; 8 to 20 mm) follicles. Cells were collected fresh or cultured in serum-free medium and treated with various factors that regulate angiogenesis and follicular development. RNA was collected for analysis of VEGFA mRNA abundance via quantitative PCR. In SMGC, prostaglandin E2 (PGE2) and follicle stimulating hormone (FSH) decreased (P < 0.05) VEGFA mRNA abundance by 30% to 46%, whereas in LGGC PGE2 and FSH were without effect (P > 0.10). In SMGC, dihydrotestosterone (DHT), sonic hedgehog (SHH) and growth differentiation factor-9 (GDF9) decreased (P < 0.05) VEGFA expression by 30% to 40%. Fibroblast growth factor-9 (FGF9) and estradiol (E2) were without effect (P > 0.10) on VEGFA mRNA in both SMGC and LGGC, whereas progesterone increased (P < 0.05) VEGFA mRNA in LGGC but had no effect in LGTC. Bone morphogenetic protein-4 (BMP4), luteinizing hormone (LH) and FGF9 increased (P < 0.05) abundance of VEGFA mRNA by 1.5- to 1.9-fold in LGTC. Insulin-like growth factor-1 (IGF1) was without effect (P > 0.10) on VEGFA mRNA in both TC and GC. An E2F transcription factor inhibitor, HLM0064741 (E2Fi), dramatically (i.e., 8- to 13-fold) stimulated (P < 0.01) the expression of VEGFA mRNA expression in both SMGC and LGTC. Abundance of VEGFA mRNA was greater (P < 0.05) in LGGC and SMGC than in LGTC. Also, SMTC had greater (P < 0.05) abundance of VEGFA mRNA than LGTC. In conclusion, VEGFA mRNA abundance was greater in GC than TC, and VEGFA expression decreased in TC during follicle development. Some treatments either suppressed, stimulated or had no effect on VEGFA expression depending on the cell type. The inhibition of E2F transcription factors had the greatest stimulatory effect of all treatments evaluated, and thus E2Fs may play an important role in regulating angiogenesis during follicle growth in cattle.////////////////// Dopamine agonist inhibits vascular endothelial growth factor protein production and secretion in granulosa cells. Ferrero H et al. (2015) Dopamine receptor 2 agonists (D2-ags) inhibit vascular endothelial growth factor (VEGF) secretion in luteinized granulosa cells (LGCs) both in vitro and in vivo. However, the mechanism of D2 regulation of the VEGF/VEGF Receptor 2 (VEGFR-2) pathway remains to be elucidated. We sought to determine the effects of D2 signaling on VEGF transcription and translation in LGCs, with the expectation of identifying potential D2-ag-based therapies for ovarian hyperstimulation syndrome (OHSS). LGCs from egg donors were cultured with chorionic gonadotropin (hCG) in the presence of Actinomycin-D (ActD) or Brefeldin-A (BFA) to evaluate the effects of a D2-ag, cabergoline (Cb2), on VEGF secretion. The contribution of the conventional Gi/Go, Gz and AKT/β-Arrestin pathways in the VEGF regulation was assessed by adding pertussis toxin (PTX), phorbol 12-myristate 13-acetate (PMA), or wortmannin (WT). While Cb2 inhibited VEGF secretion by interfering with VEGF peptide translation and secretion, inhibition of conventional D2 transduction pathways did not reverse Cb2-mediated inhibition of VEGF secretion. The effects of D2-ag on VEGF translation and secretion are mediated by D2 signaling pathways that have yet to be described. We found that D2-ag inhibits VEGF secretion at the post-transcriptional level, suggesting that D2-ag treatment should be combined with therapies that inhibit VEGF transcription, such as the employment of LH or GnRH for triggering ovulation, to improve the efficacy of OHSS prevention.////////////////// Effect of HIF-1a/VEGF signaling pathway on plasma progesterone and ovarian prostaglandin F2a secretion during luteal development of pseudopregnant rats. Pan XY et al. (2015) The corpus luteum is a temporary endocrine structure in mammals that plays an important role in the female reproductive cycle and is formed from a ruptured and ovulated follicle with rapid angiogenesis. Vascular endothelial growth factor (VEGF) is thought to be vital in normal and abnormal angiogenesis in the ovary, but the molecular regulation of luteal VEGF expression during corpus luteum development in vivo is still poorly understood at present. Therefore, we examined whether hypoxia-inducible factor-1a (HIF-1a) is induced and regulates VEGF expression and luteal function in vivo using a pseudopregnant rat model treated with a small-molecule inhibitor of HIF-1a, echinomycin. Corpus luteum development in the pseudopregnant rat ovary was determined after measuring plasma progesterone concentration and ovarian prostaglandin F2a content to reflect changes in HIF-1a and VEGF on different days of this developmental process. At day 7, the corpus luteum was formed and the expression of HIF- 1a/VEGF reached a maximum, while a significant decrease in HIF-1a/ VEGF expression was observed when luteolysis occurred at day 13. Additionally, echinomycin blocked luteal development by inhibiting VEGF expression mediated by HIF-1a and following luteal function by detecting the progesterone changes at day 7. These results demonstrated that HIF-1a-mediated VEGF expression might be an important mechanism regulating ovarian luteal development in mammals in vivo, which may provide new strategies for fertility control and for treating some types of ovarian dysfunction, such as polycystic ovarian syndrome, ovarian hyperstimulation syndrome, and ovarian neoplasia.////////////////// Effect of Antiprogesterone RU486 on VEGF Expression and Blood Vessel Remodeling on Ovarian Follicles before Ovulation. Mauro A 2014 et al. BACKGROUND The success of ovarian follicle growth and ovulation is strictly related to the development of an adequate blood vessel network required to sustain the proliferative and endocrine functions of the follicular cells. Even if the Vascular Endothelial Growth Factor (VEGF) drives angiogenesis before ovulation, the local role exerted by Progesterone (P4) remains to be clarified, in particular when its concentration rapidly increases before ovulation. AIM This in vivo study was designed to clarify the effect promoted by a P4 receptor antagonist, RU486, on VEGF expression and follicular angiogenesis before ovulation, in particular, during the transition from pre to periovulatory follicles induced by human Chorionic Gonadotropins (hCG) administration. MATERIAL AND METHODS Preovulatory follicle growth and ovulation were pharmacologically induced in prepubertal gilts by combining equine Chorionic Gonadotropins (eCG) and hCG used in the presence or absence of RU486. The effects on VEGF expression were analyzed using biochemical and immunohistochemical studies, either on granulosa or on theca layers of follicles isolated few hours before ovulation. This angiogenic factor was also correlated to follicular morphology and to blood vessels architecture. RESULTS AND CONCLUSIONS VEGF production, blood vessel network and follicle remodeling were impaired by RU486 treatment, even if the cause-effect correlation remains to be clarified. The P4 antagonist strongly down-regulated theca VEGF expression, thus, preventing most of the angiogenic follicle response induced by hCG. RU486-treated follicles displayed a reduced vascular area, a lower rate of endothelial cell proliferation and a reduced recruitment of perivascular mural cells. These data provide important insights on the biological role of RU486 and, indirectly, on steroid hormones during periovulatory follicular phase. In addition, an in vivo model is proposed to evaluate how periovulatory follicular angiogenesis may affect the functionality of the corpus luteum (CL) and the success of pregnancy. ///////////////////////// Dopamine receptor 2 activation inhibits ovarian vascular endothelial growth factor secretion in?vitro: implications for treatment of ovarian hyperstimulation syndrome with dopamine receptor 2 agonists. Ferrero H 2014 et al. OBJECTIVE To ascertain whether vascular endothelial growth factor (VEGF) secretion by luteinized granulosa cells (GCs) is modulated by the dopaminergic system in a dose-dependent fashion and how this is related to the differential efficacy of dopamine receptor 2 (D2)-agonists (D2-ag) in preventing ovarian hyperstimulation syndrome (OHSS). DESIGN The relationship between the dopaminergic system and VEGF secretion in luteinized GCs was evaluated. Archived human ovaries were immunostained to characterize D2 expression. SETTING University affiliated infertility center. PATIENT(S) Premenopausal women and egg donors. INTERVENTION(S) Luteinized GCs were cultured with the D2-ag cabergoline. Human ovarian sections were immunostained for D2. MAIN OUTCOME MEASURE(S) The VEGF was measured by ELISA and D2 expression was evaluated by In-Cell ELISA. The D2 expression throughout the luteal phase was characterized by immunohistochemistry. RESULT(S) The VEGF secretion was decreased by the D2-ag in a dose-dependent fashion. The efficiency of this process was correlated with the amount of D2 expressed by luteinized GCs. A decrease in D2 expression in ovarian sections was observed during the late luteal phase. CONCLUSION(S) The efficacy of D2-ags in preventing OHSS might rely on their capacity to inhibit VEGF secretion by luteinized GCs. Because this capacity is dose-dependent, increasing the intraovarian concentration of D2-ags should be explored as a means of increasing the efficacy of these drugs in preventing OHSS. ///////////////////////// Growth Factor Induces Vascular Endothelial Growth Factor Expression in Granulosa Cells via a trkA Receptor/ MAPK-ERK2 dependent pathway. Julio-Pieper M et al. Context: Acquisition of ovulatory competence by antral follicles requires development of an adequate vascular supply. Although it is well established that ovarian angiogenesis is cyclically regulated by vascular endothelial growth factor (VEGF), the factors controlling VEGF production by ovarian follicles remain largely unknown. Nerve growth factor (NGF) may be one of these factors, because NGF promotes angiogenesis and synthesis of angiogenic factors in other tissues and is produced by human granulosa cells (h-GCs). Objective: To determine if NGF influences the production of VEGF by h-GCs and to identify a potential signaling pathway underlying this effect. Design: A prospective experimental study. Patients: H-GCs were obtained from 41 women participating in the in vitro fertilization program of our Institution. Methods: Changes in VEGF mRNA after exposure to NGF were evaluated in cultured h-GCs by PCR and real-time PCR. The effect of NGF on VEGF secretion was determined by ELISA. The involvement of trkA, the high affinity NGF receptor, was examined by inhibiting the receptor's tyrosine kinase activity with K252a. The contribution of an ERK1/ERK2-mediated signaling pathway was identified by detecting NGF-dependent phosphorylation of these proteins and by blocking their activity with the inhibitor U0126. Results: NGF promotes VEGF production in cultured h-GCs. Blockade of trkA receptor tyrosine kinase activity blocks this effect. NGF induces MAPK ERK2 phosphorylation, and blockade of this signaling pathway prevents the NGF-induced increase in VEGF production. Conclusions: NGF promotes ovarian angiogenesis by enhancing the synthesis and secretion of VEGF from h-GCs, via a trkA- and ERK2-dependent mechanism. Christenson et al. (1997) reported the FSH and LH/CG stimulation of VEGF production by macaque granulosa cells from pre- and periovulatory follicles. Neulen et al. (1998) reported that the secretion of vascular endothelial growth factor from human luteinized granulosa cells is human chorionic gonadotrophin dependent. Laitinen et al. (1997) reported that the mRNAs of VEGF, VEGF-B, and VEGF-C are expressed in human granulosa-luteal (GL) cells and that their mRNA steady state levels are regulated in cultured human cells in an isotype-specific manner. The differential regulation of VEGF, VEGF-B, and VEGF-C in human GL cells suggests that distinct VEGF isotypes may play different roles during the vascularization of the human ovarian follicle and corpus luteum.Studies by Levitas E et al 2000 documented an in vivo increase in VEGF transcripts before ovulation in rats; disclose a marked dependance of VEGF on IL-1 beta; reveal the IL-1 beta effect to be receptor mediated and dose and time dependant and to be shared by at least two growth factors- epidermal growth factor and basic fibroblastic growth factor. Progesterone induces the expression of vascular endothelial growth factor (VEGF) 120 and Flk-1, its receptor, in bovine granulosa cells. Shimizu T et al. Vascular endothelial growth factor (VEGF) isoforms (VEGF 120 and VEGF 164) secreted by granulosa cells are involved in thecal angiogenesis during follicular development in the bovine ovary. The follicular fluid in the developing follicle includes a slight amount of the progesterone. However, the progesterone (P4) effects on VEGF120 and VEGF164 isoforms have not been well characterized in the bovine granulosa cells. We investigated the effects of progesterone on the gene expression of hypoxia-inducible factor 1alpha (HIF-1alpha, transcription factor), VEGF120, VEGF164 and Flk-1, its receptors, in cultured bovine granulosa cells. Messenger RNA expression for HIF-1alpha, VEGF120, VEGF164 and Flk-1 was quantified using real-time PCR methods. The levels of VEGF120, HIF-1alpha and Flk-1 mRNAs were increased significantly by P4 at a concentration of 10ng/ml. In contrast, the expression of VEGF 164 gene is inhibited by P4. The level of VEGF120 and Flk-1 mRNAs in the granulosa cells treated with 10ng/ml progesterone plus 1ng/ml estradiol significantly decreased compared with progesterone alone. In contrast, the addition of 1ng/ml estradiol to the culture medium increased the expression of VEGF164 gene. In conclusion, our data demonstrated that progesterone might stimulate the expression of the VEGF120 via HIF-1alpha, transcription factor, in bovine granulosa cells. These results suggest the hormone-dependent expression pattern of VEGF isoforms during follicular development. Thus, our study suggested the expression of VEGF isoforms in granulosa cells might be controlled by a different pathway during follicle development in cow. Potential role of follicle-stimulating hormone (FSH) and transforming growth factor (TGF?) in the regulation of ovarian angiogenesis. Kuo SW et al. Angiogenesis occurs during ovarian follicle development and luteinization. Pituitary secreted FSH was reported to stimulate the expression of endothelial mitogen VEGF in granulosa cells. And, intraovarian cytokine TGFb1 is known to facilitate FSH-induced differentiation of ovarian granulosa cells. This intrigues us to investigate the potential role of FSH and TGFb1 regulation of granulosa cell function in relation to ovarian angiogenesis. Granulosa cells were isolated from gonadotropin-primed immature rats and treated once with FSH and/or TGF? for forty-eight hours, and the angiogenic potential of conditioned media (GCCM) was determined using an in vitro assay with aortic ring embedded in collagen gel and immunoblotting. FSH and TGF? increased the secreted angiogenic activity in granulosa cells (FSH+TGF? > FSH ? TGFb1 > control) that was partly attributed to the increased secretion of pro-angiogenic factors VEGF and PDGF-B. This is further supported by the evidence that pretreatment with inhibitor of VEGF receptor-2 (Ki8751) or PDGF receptor (AG1296) throughout or only during the first two-day aortic ring culture period suppressed microvessel growth in GCCM-treated groups, and also inhibited the FSH+TGF?-GCCM-stimulated release of matrix remodeling-associated gelatinase activities. Interestingly, pretreatment of AG1296 at late stage suppressed GCCM-induced microvessel growth and stability with demise of endothelial and mural cells. Together, we provide original findings that both FSH and TGF? increased the secretion of VEGF and PDGF-B, and that in turn upregulated the angiogenic activity in rat ovarian granulosa cells. This implicates that FSH and TGF? play important roles in regulation of ovarian angiogenesis during follicle development. J. Cell. Physiol. ? 2010 Wiley-Liss, Inc. | ||||
| Ovarian localization | Granulosa, Theca, Luteal cells, Ovarian tumor | ||||
| Comment | Anti-VEGFA Therapy Reduces Tumor Growth and Extends Survival in a Murine Model of Ovarian Granulosa Cell Tumor. Tsoi M et al. Although angiogenesis has been proposed as a therapeutic target for the treatment of ovarian granulosa cell tumor (GCT), its potential has not been evaluated in controlled studies. To do so, we used the Pten (tm1Hwu/tm1Hwu); Ctnnb1 (tm1Mmt/+);Amhr2 (tm3(cre)Bhr/+) (PCA) mouse model, which develops GCTs that mimic the advanced disease in women. A monoclonal anti-vascular endothelial growth factor A (VEGFA) antibody was administered weekly to PCA mice beginning at 3 weeks of age. By 6 weeks of age, anti-VEGFA therapy significantly decreased tumor weights relative to controls (P < .05) and increased survival, with all treated animals but none of the controls surviving to 8 weeks of age. Analyses of PCA tumors showed that anti-VEGFA treatment resulted in significant decreases in tumor cell proliferation and microvessel density relative to controls (P < .05). However, treatment did not have a significant effect on apoptosis or tumor necrosis. The VEGFA receptor 2 (VEGFR2) signaling effector p44/p42 mitogen-activated protein kinase (MAPK), whose activity is associated with cell proliferation, was significantly less phosphorylated (i.e., activated) in tumors from the treated group (P < .05). Conversely, no significant difference was found in the activation of protein kinase B, a VEGFR2 signaling effector associated with cell survival. Together, these results suggest that anti-VEGFA therapy is effective at inhibiting GCT growth in the PCA model and acts by reducing microvascular density and cell proliferation through inhibition of the VEGFR2-MAPK pathway. Findings from this preclinical model therefore support the investigation of targeting VEGFA for the adjuvant treatment of GCT in women. In human ovaries, granulosa cells in primordial and primary follicles were VEGF negative, but at the preantral stage, the granulosa cells showed weakly positive immunostaining for VEGF. However, the VEGF immunostaining in granulosa cells was weak throughout folliculogenesis. In contrast, theca interna cells of developing follicles showed strong staining for VEGF, which was well correlated with PCNA positivity in vascular endothelial cells in the thecal layer. In atretic follicles, granulosa and theca cells were VEGF negative. In corpora lutea, VEGF was strongly expressed in both granulosa and theca lutein cells in the early luteal phase when the PCNA positivity in the endothelium increased. VEGF staining in these cells became weak in the mid- and late luteal phases (Yamamoto et al., 1997 . | ||||
| Follicle stages | Secondary, Antral, Preovulatory, Corpus luteum | ||||
| Comment | Angiogenesis in The Ovary - The Most Important Regulatory Event for Follicle and Corpus Luteum Development and Function in Cow - An Overview. Berisha B et al. (2015) In the ovary, the development of new capillaries from pre-existing ones (angiogenesis) is a complex event regulated by numerous local factors. The dominant regulators of angiogenesis in ovarian follicles and corpora lutea are the vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), insulin-like growth factor (IGF), angiopoietin (ANPT) and hypoxia-inducible factor (HIF) family members. Antral follicles in our study were classified according to the oestradiol-17-beta (E2) content in follicular fluid (FF) and were divided into five classes (E2 < 0.5, 0.5-5, 5-20, 20-180 and >180 ng/ml FF). The corresponding sizes of follicles were 5-7, 8-10, 10-13, 12-14 and >14 mm, respectively. Follicle tissue was separated in theca interna (TI) and granulosa cells (GC). The corpora lutea (CL) in our study were assigned to the following stages: days 1-2, 3-4, 5-7, 8-12 13-16 and >18 of the oestrous cycle and months 1-2, 3-4, 6-7 and >8 of pregnancy. The dominant regulators were measured at mRNA and protein expression levels; mRNA was quantified by RT-qPCR, hormone concentrations by RIA or EIA and their localization by immunohistochemistry. The highest expression for VEGF-A, FGF-2, IGF-1 and IGF-2, ANPT-2/ANPT-1 and HIF-1-alpha was found during final follicle maturation and in CL during the early luteal phase (days 1-4) followed by a lower plateau afterwards. The results suggest the importance of these factors for angiogenesis and maintenance of capillary structures for final follicle maturation, CL development and function.////////////////// Vascular endothelial growth factor A and its two receptors in human preantral follicles from fetuses, girls, and women. Abir R et al. OBJECTIVE: To investigate the expression of vascular endothelial growth factor A (VEGF-A) and that its two receptors (VEGFR1, VEGFR2) in human preantral follicles. DESIGN: Immunohistochemical, in situ hybridization, and reverse transcriptase polymerase chain reaction (RT-PCR) study of the expression of the VEGF-A system in human ovaries. SETTING: Major tertiary-care academic center. PATIENT(S): Twenty-two patients who underwent pregnancy terminations at 21-35 gestational weeks and 29 girls/women aged 5-39 years who underwent ovarian laparoscopies. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Laboratory analysis of human ovarian specimens. RESULT(S): Immunhistochemistry and in situ hybridization revealed the expression of the proteins and mRNA transcripts for VEGFR1 and VEGFR2 in oocytes, granulosa cells, and stroma cells from fetuses and girls/women. The protein for VEGF-A was detected immunohistochemically in oocytes, granulosa cells, and stroma cells from fetuses and girls. VEGF-A and VEGFR1 proteins were expressed more strongly than VEGFR2. VEGF-A(121), VEGF-A(165), and VEGF-A(189) isoforms were identified by RT-PCR in the ovarian samples from fetuses and women. CONCLUSION(S): The presence of the VEGF-A receptors, particularly in the granulosa cells, suggests that VEGF-A might be involved in proliferation initiation of primordial follicles or play an as yet unknown role in human preantral follicles. Controlled ovarian hyperstimulation with gonadotropins is followed by Ovarian Hyperstimulation Syndrome (OHSS) in some women. An unidentified capillary permeability factor from the ovary has been implicated, and VEGF is a candidate protein. Levin et al. (1998) analyzed follicular fluids (FF) from 80 women who received hormonal induction for infertility and concluded that VEGF is the follicular fluid factor responsible for increased vascular permeability, thereby contributing to the pathogenesis of OHSS. Agrawal et al. (1999) presented data to support the role of VEGF as an important nonsteroidal index of ovarian response. The VEGF rise may have an advantage over the estradiol concentration, the number of follicles, and the number of oocytes, which individually predict only 15%-25% of cases of ovarian hyperstimulation syndrome (OHSS).Localization and Quantification of Cyclic Changes in the Expression of Endocrine Gland Vascular Endothelial Growth Factor in the Human Corpus Luteum Fraser HM,et al . Angiogenesis is essential for normal growth and function of the corpus luteum. The roles of various angiogenic factors in these events are being elucidated. Endocrine gland vascular endothelial growth factor (EG-VEGF) has recently been described in the human ovary. To define the localization of EG-VEGF mRNA in the corpus luteum and determine changes in its expression, dated human corpora lutea were studied at the early, mid- and late luteal phase. Quantitative RT-PCR was employed to determine changes in EG-VEGF mRNA and compare expression to its related factor Prokineticin-2 (PK-2) and the established angiogenic factor, VEGF. In situ hybridization was used to localize sites of production of EG-VEGF. To investigate whether expression of EG-VEGF was under the influence of LH or progesterone, luteinised granulosa cells were stimulated with hCG +/- a progesterone synthesis inhibitor. EG-VEGF mRNA increased throughout the luteal phase while there was no change in VEGF mRNA. The relative abundance of RNAs based upon PCR signal intensity showed that VEGF and EG-VEGF were highly expressed while expression of PK-2 was low. EG-VEGF mRNA was localized predominantly to granulosa-derived cells of the corpus luteum. HCG stimulated both VEGF and EG-VEGF mRNA in vitro but the level of expression was not influenced by progesterone. These results establish that in the human corpus luteum EG-VEGF is principally derived from granulosa lutein cells and that its synthesis is highest during the mid to late luteal phase. | ||||
| Phenotypes |
PCO (polycystic ovarian syndrome) |
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| Mutations |
9 mutations
Species: mouse
Species: mouse
Species: None
Species: human
Species: mouse
Species: mouse
Species: mouse
Species: human
Species: human
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| Genomic Region | show genomic region | ||||
| Phenotypes and GWAS | show phenotypes and GWAS | ||||
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| created: | July 22, 1999, midnight | by: |
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| last update: | Aug. 18, 2020, 1:51 p.m. | by: | hsueh email: |
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