prothrombin may serve a broader physiologic role than simply stemming blood loss,
including the identification of multiple G protein-coupled, thrombin-activated receptors, and the well-documented
mitogenic activity of thrombin in in vitro test systems.
Lindsay E. Roach et al 2002 reported thrombin generation and presence of Thrombin Receptor in Ovarian Follicles.
Prothrombin, once converted to its enzymatically active form (i.e., thrombin), induces a broad spectrum of cellular responses in both vascular and avascular tissues. Bovine ovarian granulosa cells isolated from healthy follicles of various sizes contain both prothrombin mRNA and immunologically reactive prothrombin that appears to be identical to prothrombin in follicular fluid and plasma.
NCBI Summary:
Coagulation factor II is proteolytically cleaved to form thrombin in the first step of the coagulation cascade which ultimately results in the stemming of blood loss. F2 also plays a role in maintaining vascular integrity during development and postnatal life. Peptides derived from the C-terminus of this protein have antimicrobial activity against E. coli and P. aeruginosa. Mutations in F2 lead to various forms of thrombosis and dysprothrombinemia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2015]
General function
Ligand, Enzyme
Comment
Increased thrombin generation in women with polycystic ovary syndrome: A pilot study on the effect of metformin and oral contraceptives. Glintborg D et al. (2015) Polycystic ovary syndrome (PCOS) is associated with risk factors for cardiovascular disease (CVD) which may be modified by the use of metformin and oral contraceptives (OC). Thrombin generation (TG) measures are risk markers of CVD and address the composite of multiple factors that influence blood coagulation. This prospective, randomized, intervention study evaluated the potential influence of PCOS on TG measures and the effect of OC and/or metformin on TG measures in women with PCOS. Ninety patients with PCOS and 35 controls were included. Patients were randomized to 12 months of treatment with metformin, metformin+OC or OC alone. C-reactive protein (CRP), fibrinogen, total cholesterol, trunk fat mass, body mass index, estradiol, testosterone, sex hormone binding globulin (SHBG) as well as TG measures, i.e. the lag time for formation of thrombin, the endogenous thrombin potential (ETP), peak thrombin concentration (peak) and time to peak were determined at baseline and after 12 months of treatment. CRP and total testosterone were significantly higher and SHBG significantly lower in PCOS women than in controls (P=0.012, P<0.001 and P=0.008, respectively). The TG measures ETP, peak and lag time were increased in women with PCOS compared to controls (P<0.01). Significant correlations were observed between TG measures and fibrinogen, CRP, SHBG and fat trunk mass (P>0.01). ETP (P=0.006), peak (P=0.003) and lag time (P=0.023) remained increased after adjustment for these potential confounders. Treatment with OC and metformin+OC further increased ETP (P<0.001) and peak (P<0.005) and reduced time to peak (P<0.04). The increase in ETP was significantly lower in the metformin+OC group than in the OC group (P<0.05). Metformin alone did not affect TG significantly. PCOS is associated with increase in TG measures independent of other risk factors of CVD. OC increase TG measures further and may thus add to the increased risk of CVD already present in women with PCOS.//////////////////
Cellular localization
Secreted
Comment
Ovarian function
Follicle development
Comment
Expression regulated by
Comment
Ovarian localization
Granulosa
Comment
Lindsay E. Roach et al 2002 reported thrombin generation and presence of Thrombin Receptor in Ovarian Follicles.
Prothrombin, once converted to its enzymatically active form (i.e., thrombin), induces a broad spectrum of cellular responses in both vascular and avascular tissues. Bovine ovarian granulosa cells isolated from healthy follicles of various sizes contain both prothrombin mRNA and immunologically reactive prothrombin that appears to be identical to prothrombin in follicular fluid and plasma. When tissue factor, the primary physiological activator of thrombin generation in plasma, is used to initiate thrombin formation, the profile of prothrombin-to-thrombin conversion is similar in follicular fluid and plasma. The conclusion that biologically functional prothrombin is synthesized by granulosa cells is further supported by evidence that mRNA for -glutamyl carboxylase, an enzyme essential for the vitamin K-dependent posttranslational modification of prothrombin, is expressed in granulosa cells in a manner similar to prothrombin mRNA. Thrombin's biological effects are mediated through selective proteolytic cleavage and activation of specific receptors. Bovine granulosa cells possess thrombin receptor (PAR-1) mRNA, and as seen with prothrombin mRNA and -glutamyl carboxylase mRNA, cells isolated from small follicles possess more PAR-1 mRNA than cells from large follicles. Thrombin receptor expression by cells in close proximity to an active thrombin-generating system suggests that these factors may be important mediators of cellular function in the ovarian follicle.
Follicle stages
Comment
Endogenous thrombin potential in polycystic ovary syndrome: the association to body mass index, insulin resistance, and inflammation. Aziz M et al. (2015) The objective of this study is to investigate plasma endogenous thrombin generation in four different phenotypes of polycystic ovary syndrome (PCOS) defined by Body Mass Index (BMI) and insulin resistance (IR). PCOS is diagnosed according to the Rotterdam criteria. Multicenter cross-sectional study. Two major University Hospitals in the Capital region of Denmark. Hundred forty-eight European women with PCOS were consecutively recruited during April 2010-February 2012. Clinical examination, blood sampling, and DEXA scan were performed. Endogenous thrombin potential (ETP). PCOS women with phenotype BMI > 25 + IR have increased potential of thrombin generation. ETP is associated with total body fat mass, IR, and CRP. Obese and insulin resistant women with PCOS have elevated level of ETP corresponding to increased risk of CVD. ETP is related to well-known CVD risk factors in PCOS but not in general to the Rotterdam criteria.//////////////////
Phenotypes
Mutations
1 mutations
Species: human
Mutation name: None
type: naturally occurring fertility: infertile - non-ovarian defect Comment: Prothrombin G20210A mutation, hypogonadotropic hypogonadism, and generalized vitiligo-related ischemic stroke in a young adult. Varoglu AO et al. PURPOSE: Cerebral infarction is a rare neurological situation in young adults, usually caused by genetic factors. We report here a case of multiple cerebral infarctions with prothrombin G20210A mutation, hypogonadotropic hypogonadism, and generalized vitiligo as a first case report. CASE REPORT: A 17-year-old female adolescent was admitted to our clinic due to a change in mental status. The patient's neurological examination revealed loss of consciousness and the presence of tetraparesia. Generalized vitiligo was also detected. Magnetic resonance imaging (MRI) and diffusion-weighted investigations (DWIs) showed acute ischemic stroke in the bilateral cerebellum, pons and left occipital regions. Heterozygote prothrombin G20210A mutation was found upon genetic examination. She had never had a menstrual cycle. Laboratory data revealed that the level of luteinizing hormone (LH) was 0.5 mIU/mL (1.1-11.6) and follicle-stimulating hormone (FSH) was 1.7 mIU/mL (2.8-11.3). Therefore, she was diagnosed with hypogonadotropic hypogonadism. The causes of ischemic stroke are heterozygote prothrombin G20210A mutation, generalized vitiligo, and hypogonadotropic hypogonadism. After treatment, the patient's neurological deficit partially improved and she was discharged. CONCLUSION: In order to identify the etiology of ischemic stroke, we suggest physicians take into account heterozygote prothrombin G20210A mutation and endocrine abnormalities, especially hypogonadotropic hypogonadism and generalized vitiligo.