Study of subacute renal toxicity of Bisphenol A in rats

Bisphenol A (BPA) falls in the category of hormonal disruptors due to its widespread application, and several studies have revealed its toxicity in different doses. However, few studies have investigated the effect of BPA on the renal system. Therefore, the present study aimed to investigate the effect of BPA on renal system function in rats.

Initially, the rats were divided into 6 groups (n=6). Group 1 received only the carrier substance. The rats in the second to sixth groups were gavaged with BPA in 0.1, 1, 10, 50, and, 100 mg/kg/BW/day doses for 29 days, respectively. On the 30th day, blood samples were taken from the heart and kidney tissues were separated after collecting 24 h urine. Biochemical parameters including urea, creatinine, total urine and serum protein, and serum albumin were measured subsequently. Eventually, kidney tissue was sent to a laboratory for histological examination.

There was no significant difference in serum creatinine levels in rats treated with different doses of bisphenol A. However, its level in urine increased at 50 mg/kg dose, compared to 1 and 10 mg/kg doses (P<0.001). Serum and urine urea increased significantly only at of 10 mg/kg dose, compared to 1 and 0.1 mg/kg doses (P<0.001). Serum albumin was reduced at 100 mg/kg dose, compared to controls. Total serum protein decreased at doses of 50 and 100 mg/kg, compared to controls and increased in urine at 50mg/kg dose (P<0.001). The protein/creatinine ratio increased significantly at doses of 1 to 50 mg/kg (P<0.001). Histological examination also revealed that BPA caused degenerative, infiltration, and dilation changes in kidney tissue in a dose-dependent manner.

Based on the obtained data, BPA at 50 and 100 mg/kg concentrations could lead to kidney tissue damage in rats and subsequent renal failure.