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@#Introduction: Investigations relating to the effect of stress on reproductive outcome, offspring survival rate and chances of still births are currently attracting global concern. The present study evaluated the effect of maternal gestation induced-stress in the altered reproductive outcome of adult female Wistar rats, offspring sex – ratio and survival following exposure to different stress models. Methods: The study protocol involved two parts. Seventy-eight adult healthy female Wistar rats aged between 12 – 14 weeks and weighing between 150-180g were procured and utilized for part 1 study. The rats were exposed to three stressors; restraint, mirror and intruder, respectively, for three hours per day for three weeks. For part 2 experiment twenty-four female offspring rats from the part 1 study were used. Results: Exposure of rats to the varying stressors increased gestate on length, decreased mean pup weights and litter size at birth especially when the rats were stressed by exposure to restraint or intruder stressor. The effect of stress on gestation period, pup weights and litter size were largely variable and dependent on the nature of stressor applied. There was significant (p<0.05) reduction in the survival rates of offspring of rats exposed to the different nature of stressors especially when stressed with restraint or intruder stressors. The stressors’ impact was greatest when the rats were exposed to the varying stressors up to the end of the 2nd trimester and beyond. Furthermore, the male sex ratio of offspring of stressed rats was significantly (p<0.05) reduced than the females. Conclusion: Stressful maternal condition tends to compromise the fetal outcome, sex ratio specificity and the survival rate of offspring.
RESUMO
The present study examines the effect of some bioactive constituents of Vernonia amygdalina crude extract and fractions on enzymes involved in glucose metabolism and treatment of Diabetes Mellitus. Fresh Vernonia amygdalina leaves were extracted using ethanol. Four fractions from this extract were obtained by liquid-liquid fractionation technique using solvents of varying polarity and the bioactive compounds were identified by Gas Chromatography–Mass Spectrum (GC-MS) analysis. Resultant fractions were administered at 300 mg/kgBW to streptozotocin (60 mg/kg) induced diabetic wistar rats. The results shows that various fractions produced a fall in the fasting blood glucose level in diabetic rats; Chloroform (65.85%), ethyl acetate (69.65%) Benzene (45.59%) and Butanol (37.31%) and all fractions showed increase in the activity of glucose metabolic enzymes (hexokinase, pyruvate kinase, Glucose-6-phosphate dehydrogenase (G6PDH) and Diaphorase (NADPH) between 20–81%, significantly higher than that of the metformin (reference drug at 50 mg/kg). Administration of Crude ethanolic leaf extracts of Vernonia amygdalina at dose of 300 mg/kg produced a fall (81.45%) in the fasting blood glucose level and subsequent increase in glucose metabolic enzyme activity (hexokinase, pyruvate kinase, Glucose-6-phosphate dehydrogenase (G6PDH) and Diaphorase (NADPH) (20–35%) in the diabetic Wistar rats after 28 days of treatment. GC-MS analysis showed that the plant and its fractions possess hypoglycaemic bioactive constituents such as Phytol, Palmitic acid, stearic acid and oxirane. The findings suggest that Vernonia amygdalina extract reduced the hyperglycaemic effect of streptozotocin-induced diabetes through its effect on glucose metabolism by promoting enzymes of the glycolytic and the pentose phosphate pathway, a property attributable to its active chemical constituents.