Effects of IGF-1, TGF-α plus TGF-β1 and bFGF on in vitro survival, growth and apoptosis in FSH-stimulated buffalo (Bubalis bubalus) preantral follicles

ObjectiveInvestigate the effect of various growth factors viz. IGF-I, TGF-α + TGF-β1 and bFGF either alone or in combination, with FSH on in vitro growth, survival, antrum formation, steroidogenesis and apoptosis of buffalo preantral follicles (PFs).MethodsBuffalo ovaries were collected from abattoir; PFs were isolated and divided into five treatment groups. TCM-199 supplemented with 10% FBS, 1% ITS + EGF + FSH control (group a), control + IGF-I (group b), control + TGF-α + TGF-β1 (group c), control + IGF-I + TGF-α + TGF-β1 (group d) and control + bFGF (group e). Progesterone (P4) and 17β-estradiol (E2) concentrations were evaluated by RIA and apoptosis by TUNEL assay.ResultsTGF-α + TGF-β1 inhibited follicular survival and induced oocyte apoptosis, while IGF-I + TGF-α + TGF-β1 suppressed this inhibitory action. IGF-I significantly (P < 0.05) enhanced the follicle survival, growth and induced antrum formation. FGF had greater effects on both survival and growth rate of oocytes than other treatment groups. Progesterone and estradiol accumulation was significantly (P < 0.05) greater in presence of FGF and IGF-I than TGF-α + TGF-β1.ConclusionSurvival, growth, antrum formation and steroidogenesis are stimulated by IGF-I and bFGF, whereas TGF-α + TGF-β1 inhibited growth and survival of PFs which led to induced oocyte apoptosis in buffalo PFs.