ABSTRACT

Increased oxidative stress arising from the maternal hyperglycemic-induced disturbances in fetal metabolism has been suggested to play a role in the pathogenesis of disturbed embryogenesis in diabetic pregnancies. Maternal diabetes in pregnancy and the associated hyperglycemia is also believed to expose the fetus to disturbed metabolic conditions in-utero creating a ‘metabolic memory’ that programs the fetus for glucose intolerance, diabetes mellitus and obesity later in life. Bitter kola (Garcinia kola) is a medicinal plant with a wide range of pharmacological effects including ant diabetic and antioxidant effects. In this study, the effects of aqueous extracts of Garcinia kola seed on the pregnancy outcome and early postnatal development of the offspring of pregnant alloxan diabetiPc and non-diabetic Wister rats was studied. Forty (40) nulliparous female Wister rats were used. Pregnancy was induced in all the rats, and diabetes induced in twenty (20) making two groups; pregnant diabetic and pregnant non-diabetic. These two groups were further subdivided into four groups of five rats each receiving different concentrations of the extract as follows; control, 100mg, 200mg, and 300mg/kg of body weight. The extract was administered orally as a single dose daily throughout gestation. The extract caused a reversal of the significant reduction of weight gain and significantly increased weight gain among the pregnant diabetic rats. It also significantly reduced the fasting blood glucose concentration in the hyperglycemic diabetic rats in a dose-dependent manner to values close to normal. These may be due to the insulinogenic effect of kolaviron an active principle of Bitter kola The extract significantly increased the litter size among the diabetic pregnant rats in a dose-dependent manner when compared with their control that showed a statistically significant reduction in litter size. This observed effect of the extract may be because of the anti-oxidative stress effects of kolaviron and ascorbic acid (constituents ofBitter kola) observed in previous studies. The extract also reduced the birth weight, excessive early post natal growth, and the high fasting blood glucose concentration on the weaning (21st) day, among the offspring of diabetic rat in a dose-dependent manner when compared with those of the diabetic pregnant control group. These may be due to the blood glucose lowering effect of the aqueous extract of Bitter kola seed among their mothers which leaves little or no excess glucose for the fetus to absorb and as such avert the major complications of diabetic pregnancy. The result of this study suggests that Bitter kolamay have a protective effect against the adverse effects of diabetes in pregnancy on both the mother and the offspring.