Dioscorea hispida supplementation-induced histological changes in maternal rat's liver and placenta / Shahira Fariza Maslan

Dioscorea hispida (D. hispida) is a well-known poisonous wild tuber plants used as food in Malaysia. The study regarding D. hispida intoxicating effect on liver and placental tissues including its safety for consumption require investigation. Therefore, this study was aimed to investigate the effect of D. hispida supplementation on maternal rat via histological examination of the maternal rat's liver and placenta. A total of 30 pregnant Sprague-Dawley rats were divided randomly into five groups (n=6) consists of a negative control group and four D. hispida supplementation groups. The negative control group rat's was administered with distilled water while the rats in other four groups were supplemented with increasing dosage of D. hispida aqueous extract; 250 mg/kg, 500 mg/kg, 1000 mg/kg, and 2000 mg/kg via oral gavage. The supplementation was given during organogenesis period and euthanization was done on day 21. Both tissues were harvested and routinely processed for histological examination. The liver weight of rats in all supplemented groups were increased with only rats of 2000 mg/kg D. hispida extract group showed significant liver weight increment compared to control group (p < 0.05). The placental weight of rats in 250 mg/kg, 500 mg/kg and 1000 mg/kg extract supplemented groups increased with reduction of placental number compared to control but not significantly difference. Placental weight of rat in group 2000 mg/kg extract decreased compared to control with presence of unformed placenta. Photomicrograph of maternal rats' liver and placental tissues in all supplemented groups showed significant morphology changes especially at dose 2000 mg/kg extract indicating possible toxic effect of the extract on the liver and placenta. Histological examination of maternal rats' liver in all supplemented groups undergo degeneration which characterized by hepatocyte swelling, cytoplasmic vacuolation, cytolysis, margination and clumping of nucleus chromatin. The placental histological examination of the maternal rats in all supplemented groups presented changes of the basal and labyrinth zone. The glycogen cells were reduced with fibrin deposition in the basal zone while in the labyrinth zone, there were irregular vessel formation in the extract supplemented groups. In conclusion, D. hispida plant aqueous extract exerted histological changes in maternal rat's liver and placenta tissues which indicate that this extract potentially gives deleterious effect to both tissues.