The Effects of Fructose on the Developmental Competence, Bio-chemical Biomarkers and Apoptotic Gene Expression by Murine Oocytes

THE goal of the current study was to investigate the effects of fructose supplementation in the culture medium on in vitro maturation, and the developmental competence of murine oocytes, biochemical markers and the expression of apoptotic and HIF-1 alpha in cumulus oocyte cells (COCs). Murine oocytes were matured in IVF media supplemented with 1.25, 2.75 and 5-mM fructose. The developmental parameters (MI, MII, GVBD, degenerated and activated cells) were examined with NO, GPX, GSH, MDA, and TAC biomarkers. The expression of mRNA for apoptotic genes by COCs were evaluated. The low dosage improves significantly (P<0.05) the developmental competence markers than the control and higher doses of fructose. In vitro-matured mouse oocytes with 1.25 mM fructose showed a significant increase (P<0.05) in NO level in the In-vitro matured when compared with the control and other groups. The GPX concentrations in the in-vitro matured oocytes showed a significant decrease (P<0.05) with 5mM fructose. The MDA levels in the vitro-matured oocytes were higher (P<0.05) when the murine oocytes were exposed to 2.75 mM of fructose. The TAC in the oocyte showed no changes (P<0.05) when the oocytes were exposed to both 1.25 mM. Moreover, the supplementation of IVM media showed a down regulation of apoptotic and HIF-1 alpha genes when compared with the control and high dosage supplementation (P<0.05). Altogether, the supplementation of IVM media with lower dosage of fructose improves the developmental competence markers in the murine oocytes via its effects on oxidant and antioxidant activity and downregulation of apoptotic and HIF-1 alpha genes.