The effect of swimming endurance training and silymarin supplementation during pregnancy on maternal cadmium exposure - induced apoptosis in hepatocytes of rat neonates

Both cell proliferation and apoptosis are required forproper development of the neonatal parenchyma of the liver. This study was conducted to evaluate the effects of swimming endurance training and silymarin supplementation during pregnancy on maternal cadmium – induced apoptosis in hepatocytes of neonates. 72 pregnant Wistar rats (200 ± 20 g) were divided into 9 groups. Cadmium chloride was given orally (400mg/kg in drinking water) from the first day of pregnancy. Training protocol was included 60 minutes swimming for 5 days per week during pregnancy. Silymarin (100 mg/kg) was injected subcutaneously three times a week. Liver tissue was removed two days after born and apoptotic index also determined by nonradioactive in situ end labeling method using TUNEL immunocytochemical technique. The ANOVA and post hoc LSD tests were used to analyze the collected data at p≤ 0. 05. Apoptotic index of hepatocytes were decreased significantly in cadmium- silymarin and cadmium- silymarin-training groups (p < 0. 001). Swimming training caused no significant changes in apoptotic index of hepatocytes (p = 0. 83). Swimming endurance training during pregnancy probably have no effect on maternal cadmium – induced of apoptosis in hepatocytes of neonates، however، silymarin could reduce it.