Visit our Expo - Redox and Inflammation signaling 2012

Session XVII : Cell signaling in health and disease Poster XVII, 40
Signaling pathways regulating production of hyaluronic acid in pig oocyte-cumulus cell-
complexes
Radek Procházka and Eva Nagyová
Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech
Republic, Lib2chov, 277 21 Czech Republic. E-mail: prochazka@iapg.cas.cz
Cumulus cells undergo an extensive expansion following the preovulatory surge of
gonadotrophins due to increased production of hyaluronic acid (HA) and its deposition in
extracellular spaces. In vitro, the expansion can be stimulated with FSH in all mammalian
species. The insulin like-growth factor-I (IGF-I) can modify the action of FSH on cumulus
cells. The objective of this study was to characterize mechanisms by which the IGF-I affects
the FSH-stimulated production and deposition of HA in pig oocyte-cumulus complexes
(OCCs). For this purpose, signaling pathways activated in cumulus cells by IGF-I were
studied and their importance for production of HA was assessed. OCCs isolated from 3-5 mm
follicles were cultured in M-199 medium supplemented with 3 mg/ml polyvinyl pyrrolidone
under an atmosphere of 5% CO2 in air for 24 h. To quantify production of HA, OCCs were
cultured in the presence of 2.5 µCi of tritiated glucosamine hydrochloride and the
incorporated label was measured by a liquid scintillation counter in medium containing OCCs
(total HA) or within the complexes alone (retained HA). We found that production and
retention of HA was significantly higher in OCCs cultured in medium with FSH (10 ng/ml)
than in control group cultured without FSH (P