NCBI Summary:
Granulins are a family of secreted, glycosylated peptides that are cleaved from a single precursor protein with 7.5 repeats of a highly conserved 12-cysteine granulin/epithelin motif. The 88 kDa precursor protein, progranulin, is also called proepithelin and PC cell-derived growth factor. Cleavage of the signal peptide produces mature granulin which can be further cleaved into a variety of active, 6 kDa peptides. These smaller cleavage products are named granulin A, granulin B, granulin C, etc. Epithelins 1 and 2 are synonymous with granulins A and B, respectively. Both the peptides and intact granulin protein regulate cell growth. However, different members of the granulin protein family may act as inhibitors, stimulators, or have dual actions on cell growth. Granulin family members are important in normal development, wound healing, and tumorigenesis. [provided by RefSeq, Jul 2008]
General function
Ligand, Hormone, Cytokine, Growth factor
Comment
Cellular localization
Secreted
Comment
Increased expression of PGRN protein in follicular fluid and mRNA in granulosa cells in overweight patients with polycystic ovary syndrome. Zhou D et al. (2017) Obesity and low-grade chronic inflammation play critical roles in pathological process of PCOS. PGRN is an adipokine and was recently reported that it could induce a low-grade chronic inflammatory state and plays a functional role in insulin resistance associated with obesity. The overall goal of the present study was to evaluate the levels of PGRN in follicular fluid (FF) and the expression of PGRN in granulosa cells (GCs) with respect to the quality of the oocytes both in patients with PCOS and in the normal ovary during COH cycles. Ninety-two patients underwent IVF-ET were divided into four groups based on body mass index: normal-weight PCOS group; overweight PCOS group; non-overweight control group and overweight control group. FF samples and GCs were collected at the time of oocyte retrieval. The PGRN, TNF-α, IL-6 and MCP-1 levels were measured by ELISA, and the mRNA expression of PGRN in GCs was detected by real-time polymerase chain reaction. Analysis of PGRN expression revealed that PGRN levels in FF and the mRNA expression of PGRN in GCs were higher in patients with PCOS than in control patients, and higher in overweight patients than in the normal-weight patients; PGRN in FF of PCOS was positively correlate with basal testosterone and FF TNF-α，but negative correlation with retrieved oocytes number CONCLUSION: This study suggests that PGRN may be a crucial determinant of fertilization success for PCOS patients.//////////////////