Piceatannol inhibits oxidative stress through modification of Nrf2-signaling pathway in testes and attenuates spermatogenesis and steroidogenesis in rats exposed to cadmium during adulthood

Background: Cadmium (Cd) is considered a heavy metal and potential pollutant to the environment. Purpose: The purpose of this study was to evaluate the protective potential of piceatannol (PT; 10 mg/kg body weight/day) against cadmium (Cd; 5 mg/kg body weight/day)-induced testicular dysfunction in Wistar rats. Materials and methods: Rats were randomly divided into four groups: control, PT, Cd, and Cd + PT. Results: Treatment with Cd resulted in a significant decrease in body, testicular, and epididymal weights, sperm quantity and quality, steroidogenic marker-enzyme activities, mRNA- and protein-expression levels of SF1, StAR, and P450 side chain-cleaving enzyme, and serum male sex hormonal levels when compared to controls. Testicular malondialdehyde levels were significantly increased, with a significant reduction in enzymatic and nonenzymatic antioxidants in Cd-treated rats compared to control rats. Testicular histomorphometric results supported the biochemical and molecular alterations observed in the study. In addition, significant downregulation in mRNA- and protein-expression levels of cytosolic Nrf2, HO1, gamma GCS, GPx, and NQO1, as well as significant upregulation in mRNA- and protein-expression levels of Nrf2 and Keap1 in testicular tissue, were noticed in rats administered Cd. PT treatment inCd-treated rats caused marked alleviation in body and organ weights, sperm analysis, steroidogenesis, serum hormonal levels, histomorphometric changes, and oxidative and antioxidative status in testes when compared to Cd alone-treated rats. Further, treatment of rats with PT1 showed a marked improvement in mRNA- and protein-expression levels of Nrf2 and its regulated genes and proteins. Conclusion: The present study provides compelling evidence that PT treatment results in significant protection against Cd-induced testicular dysfunctions, such as spermatogenesis, steroidogenesis, and oxidative stress in rats, possibly through modification of the Nrf2-Keap1 signalling pathway.