Preliminary Investigation on the Effect of Aqueous Seed Extract of Soybean (Glycine max) on the Placenta of Wistar rats

Abstract

Background: Glycine max is a type of legume that is extensively cultivated for its versatile edible bean and has significant concentrations of nutritional minerals. However, high intakes of soy isoflavones have been linked to potential adverse effects. This study investigated the effects of aqueous seed extract of Soybean (Glycine max) on the placenta of Wistar rats.

Materials and method: Twenty-four (24) pregnant animals were allotted to three groups with eight (8) rats each. Group A served as the control, Group B and C were orally administered with 250mg/kg and 500mg/kg body weight of soybean respectively. On day 19 of pregnancy the rats were sacrificed. The placenta was harvested, weighed and diameter was measured. Likewise, each fetus was weighed and the crown rump length (CRL) was measured. Placenta tissues were fixed in formal-saline, processed and stained with H&E.

Result: There was a significantly lower fetal weight in the group administered with 250mg/kg and 500mg/kg of soybean, whereas, no significance was observed in placental weights compared to control. Fetal-placenta ratio was significantly lower in the group 500mg/kg compared to control. The placenta major and minor diameters were significantly lower in the group 500mg/kg while the 250mg/kg group was significantly lower in placenta minor diameter only compared to control. The CRL was significantly lower in the 500mg/kg group compared to control. Histological results showed that Glycine max affected the cystic degeneration of glycogen cell islands of the placenta in a dose-dependent manner.

Conclusion: Ultimately, increased consumption of soybean impaired intrauterine growth and was also a source of distress to the fetus. It is therefore advised that pregnant females consume it with caution.