Fermented whey modulated AFB1 and OTA-induced hepatotoxicity and nephrotoxicity in vivo. A relative and absolute quantification about sex differences

Aflatoxin B1 (AFB1) and ochratoxin A (OTA) are well-known to promote hepatotoxicity and nephrotoxicity in vivo, which may be counteracted by natural compounds like fermented whey (FW). Carbamoyl phosphate synthetase 1 (CPS1) and kidney injury molecule 1 (KIM-1) are typical biomarkers used to detect liver and kidney damage, respectively. Thus, RT-qPCR and droplet digital PCR (ddPCR) analysis were performed to assess the potential beneficial effect of FW against AFB1 and OTA hepatotoxicity and nephrotoxicity in male and female Wistar rats by analyzing the altered gene expression of hepatic CPS1 and renal KIM-1 after 28 days of oral exposure. In male livers, the most damaging treatment was AFB1 by reducing CPS1 expression, which was totally reversed by FW-administration. This bioactive compound also improved gene expression changes induced by OTA and mycotoxins mixture. In female livers, a significant CPS1 overexpression was observed for each exposure performed, in which FW-supplementation reported no remarkable differences compared with mycotoxins exposure. Conversely, in the kidneys of male and female rats, exposure to mycotoxins promoted renal damage by altering KIM-1 gene expression, being OTA-exposure the most harmful condition. In both sexes, ddPCR analysis demonstrated that FW-addition modulated mycotoxins induced KIM-1 gene expression changes, thus reducing kidney damage. In this organ, sex-related responses were not clearly observed. Therefore, these findings confirmed that AFB1 and OTA-promoted hepatotoxicity and nephrotoxicity in vivo, which could be modulated by dietary FW supplementation.