Bisphenol A aggravates renal ischemia–reperfusion injury by disrupting mitochondrial homeostasis and N-acetylcysteine mitigates the injurious outcomes

Abstract

© 2019 International Union of Biochemistry and Molecular Biology Exposure to bisphenol A (BPA), a chemical generally used in consumer products, becomes a global public health concern, as humans are increasingly exposed through their daily consuming activities. Renal ischemia–reperfusion (RIR) is the major cause of acute kidney injury with high prevalence and increased long-term risks for multiple comorbidities and mortality. As the kidney is susceptible to these conditions, we explored whether the outcomes following the RIR episode could be influenced by BPA exposure, and investigated the therapeutic possibility by N-acetylcysteine (NAC) including the mechanisms involved. Three groups of male Wistar rats were fed with vehicle, BPA 5, and 50 mg/kg, respectively, for five consecutive weeks then underwent the sham operation. Three other groups with identical treatment underwent bilateral renal IR induction (45-min ischemia followed by 24-hr reperfusion). An additional RIR group was treated with BPA 50 plus NAC 100 mg/kg. BPA-exposed rats that encountered RIR episode showed dose-dependent worsening of RIR injury as evidenced by augmentations of renal dysfunction and histopathological abnormalities, oxidative stress, apoptosis, mitochondrial functional impairment, mitochondrial dynamic, and mitophagy disproportion compared with the vehicle-exposed RIR group. The NAC therapy considerably attenuated the exacerbated effects of BPA, which was associated with increased AMP-activated protein kinase (AMPK), PGC-1α, silent information regulator 3 or sirtuin 3 (SIRT3), and mitofusin 2 (MFN2) expressions but decreased Phosphorylated dynamin-related protein 1 (p-DRP1)/Dynamin-related protein 1 (DRP1), PTEN-induced putative kinase (PINK), and PARKIN expressions. These findings reveal the detrimental effect of repeated BPA exposure on the renal outcomes following the IR episode, and further demonstrate the protective efficacy of NAC by maintaining mitochondrial homeostasis, which is, partly, mediated through the AMPK-PGC-1α-SIRT3 axis.