Dissemin is shutting down on January 1st, 2025

Published in

BioScientifica, Reproduction, 4(141), p. 467-479, 2011

DOI: 10.1530/rep-10-0419

Links

Tools

Export citation

Search in Google Scholar

Expression and effect of resistin on bovine and rat granulosa cell steroidogenesis and proliferation

This paper is made freely available by the publisher.
This paper is made freely available by the publisher.

Full text: Download

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

Resistin, initially identified in adipose tissue and macrophages, was implicated in insulin resistance. Recently, its mRNA was found in hypothalamo–pituitary axis and rat testis, leading us to hypothesize that resistin may be expressed in ovary. In this study, we determined in rats and cows 1) the characterization of resistin in ovary by RT-PCR, immunoblotting, and immunohistochemistry and 2) the effects of recombinant resistin (10, 100, 333, and 667 ng/ml)±IGF1 (76 ng/ml) on steroidogenesis, proliferation, and signaling pathways of granulosa cells (GC) measured by enzyme immunoassay, [3H]thymidine incorporation, and immunoblotting respectively. We observed that resistin mRNA and protein were present in several bovine and rat ovarian cells. Nevertheless, only bovine GC abundantly expressed resistin mRNA and protein. Resistin treatment decreased basal but not IGF1-induced progesterone (P<0.05; whatever the dose) and estradiol (P<0.005; for 10 and 333 ng/ml) production by bovine GC. In rats, resistin (10 ng/ml) increased basal and IGF1-induced progesterone secretion (P<0.0001), without effect on estradiol release. We found no effect of resistin on rat GC proliferation. Conversely, in cows, resistin increased basal proliferation (P<0.0001; for 100–667 ng/ml) and decreased IGF1-induced proliferation of GC (P<0.0001; for 10–333 ng/ml) associated with a decrease in cyclin D2 protein level (P<0.0001). Finally, resistin stimulated AKT and p38-MAPK phosphorylation in both species, ERK1/2-MAPK phosphorylation in rats and had the opposite effect on the AMPK pathway (P<0.05). In conclusion, our results show that resistin is expressed in rat and bovine ovaries. Furthermore, it can modulate GC functions in basal state or in response to IGF1in vitro.