This study investigates the effects of bisphenol A (BPA) contamination on the kidney and the possible protection by melatonin in experimental rats and isolated mitochondrial models. Rats exposed to BPA (50, 100, and 150 mg/kg, i.p.) for 5 weeks demonstrated renal damages as evident by increased serum urea and creatinine and decreased creatinine clearance, together with the presence of proteinuria and glomerular injuries in a dose-dependent manner. These changes were associated with increased lipid peroxidation and decreased antioxidant glutathione and superoxide dismutase. Mitochondrial dysfunction was also evident as indicated by increased reactive oxygen species production, decreased membrane potential change, and mitochondrial swelling. Coadministration of melatonin resulted in the reversal of all the changes caused by BPA. Studies using isolated mitochondria showed that BPA incubation produced dose-dependent impairment in mitochondrial function. Preincubation with melatonin was able to sustain mitochondrial function and architecture and decreases oxidative stress upon exposure to BPA. The findings indicated that BPA is capable of acting directly on the kidney mitochondria, causing mitochondrial oxidative stress, dysfunction, and subsequently, leading to whole organ damage. Emerging evidence further suggests the protective benefits of melatonin against BPA nephrotoxicity, which may be mediated, in part, by its ability to diminish oxidative stress and maintain redox equilibrium within the mitochondria.

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Mitochondrial impairment ensuing from oxidative imbalance is related to adverse consequences of bisphenol A (BPA), a globally utilized industrial chemical. Recent evidence reveals sirtuin 3 (SIRT3) as a key regulator of mitochondrial homeostasis; however, its role in BPA toxicity remains unidentified. This study explored the potential benefits of N-acetylcysteine (NAC), an effective antioxidant, against BPA toxicity in the kidney and liver, and examined whether SIRT3 was involved in this condition. Male Wistar rats were fed with vehicle, BPA (5, 50 mg/kg), BPA (50 mg/kg) plus NAC (100 mg/kg) and were evaluated after 5 weeks. NAC treatment significantly diminished BPA-induced kidney and liver functional disorders, histopathological alterations, oxidative stress, and apoptosis. The increased mitochondrial reactive oxygen species, the disrupted membrane potential, the swelling, and the impaired mitochondrial fission caused by BPA were also mitigated upon concurrent treatment with NAC. The benefits of NAC were associated with enhanced AMPK-PGC-1α-SIRT3 signaling protein expressions, which led to decreased acetylation of superoxide dismutase 2 (SOD2) and increased expression of mitochondrial antioxidant manganese superoxide dismutase (MnSOD). The findings demonstrate the efficacy of NAC in protecting BPA-induced kidney and liver injury, which, in part, is mediated by activating SIRT3 and improving mitochondrial function, dynamics, and oxidative imbalance.

Nephrotoxicity is recognized as a serious disorder affected by chronic cadmium exposure. Imbalance between radical generation and elimination is considered a critical factor involved in the initiation and progression of renal injury caused by this heavy metal. The present study investigated the possible protection by catechin, a natural phenolic antioxidant, against cadmium nephrotoxicity and elucidated its potential mechanism. Male Wistar rats were assigned to receive vehicle, cadmium (CdCl 2 mg/kg, i.p.) and cadmium plus catechin (25, 50, and 100 mg/kg, orally, respectively). After 4 weeks of treatment, rats exposed to cadmium demonstrated a marked rise in blood urea nitrogen and creatinine, a fall in creatinine clearance, and renal pathologies like severe tubular damage, apoptosis, and abnormal mitochondrial structure. Significant increases in malondialdehyde, nitric oxide, and tumor necrosis factor-alpha, while reductions in antioxidant thiols, superoxide dismutase, and catalase, were also detected in the kidney tissues of cadmium-intoxicated rats. These alterations were associated with mitochondrial dysfunction as supported by an increase in mitochondrial reactive oxygen species production and a decline in mitochondrial membrane potential. Treatment with catechin significantly attenuated all the changes caused by cadmium. These findings suggest that catechin effectively protects the kidney against toxic effect of cadmium, presumably through its antioxidant, anti-inflammation, and mitochondrial protection. The study outcomes not only add evidence to reinforce the medical benefits of catechin but also, most importantly, give rise to a prospect of developing renal preventive strategy for individuals who are at risk of cadmium contamination by means of catechin supplementation.

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.

Distant organ liver damage after acute kidney injury (AKI) remains a serious clinical setting with high mortality. This undesirable outcome may be due to some hidden factors that can intensify the consequences of AKI. Exposure to bisphenol A (BPA), a universal chemical used in plastics industry, is currently unavoidable and can be harmful to the liver. This study explored whether BPA exposure could be a causative factor that increase severity of remote liver injury after AKI and examined the preventive benefit by N-acetylcysteine (NAC) in this complex condition. Male Wistar rats were given vehicle, BPA, or BPA + NAC for 5 weeks then underwent 45 min renal ischemia followed by 24 h reperfusion (RIR), a group of vehicle-sham-control was also included. RIR not only induced AKI but produced liver injury, triggered systemic oxidative stress as well as inflammation, which increasing severity upon exposure to BPA. Given NAC to BPA-exposed rats diminished the added-on effects of BPA on liver functional impairment, oxidative stress, inflammation, and apoptosis caused by AKI. NAC also mitigated the abnormalities in mitochondrial functions, dynamics, mitophagy, and ultrastructure of the liver by improving the mitochondrial homeostasis regulatory signaling AMPK-PGC-1α-SIRT3. The study demonstrates that NAC is an effective adjunct for preserving mitochondrial homeostasis and reducing remote effects of AKI in environments where BPA exposure is vulnerable.

Human health hazards caused by bisphenol A (BPA), a precursor for epoxy resins and polycarbonate-based plastics, are well documented and are closely associated with mitochondrial impairment and oxidative imbalance. This study aimed to assess the therapeutic efficacy of N-acetylcysteine (NAC) on renal deterioration caused by long-term BPA exposure and examine the signaling transduction pathway involved. Male Wistar rats were given vehicle or BPA orally for 12 weeks then the BPA-treated group was subdivided to receive vehicle or NAC concurrently with BPA for a further 4 weeks, while the vehicle-treated normal control group continued to receive vehicle through to the end of experiment. Proteinuria, azotemia, glomerular filtration reduction and histopathological abnormalities caused by chronic BPA exposure were significantly reduced following NAC therapy. NAC also diminished nitric oxide and lipid peroxidation but enhanced renal glutathione levels, and counteracted BPA-induced mitochondrial swelling, increased mitochondrial reactive oxygen species production, and the loss of mitochondrial membrane potential. The benefit of NAC was related to the modulation of signaling proteins in the AMPK-SIRT3-SOD2 axis. The present study shows the potential of NAC to restore mitochondrial integrity and oxidative balance after long-term BPA exposure, and suggests that NAC therapy is an effective approach to tackle renal deterioration in this condition.

Diabetic nephropathy (DN) is the primary cause of end-stage renal disease worldwide. Oxidative stress and mitochondrial dysfunction are central to its pathogenesis. Rice husk, the leftover from the milling process, is a good source of phytochemicals with antioxidant activity. This study evaluated the possible protection of purple rice husk extract (PRHE) against diabetic kidney injury. Type 2 diabetic rats were given vehicle, PRHE, metformin, and PRHE+metformin, respectively, while nondiabetic rats received vehicle. After 12 weeks, diabetic rats developed nephropathy as proven by metabolic alterations (increased blood glucose, insulin, HOMA-IR, triglycerides, cholesterol) and renal abnormalities (podocyte injury, microalbuminuria, increased serum creatinine, decreased creatinine clearance). Treatment with PRHE, metformin, or combination diminished these changes, improved mitochondrial function (decreased mitochondrial swelling, reactive oxygen species production, membrane potential changes), and reduced renal oxidative damage (decreased lipid peroxidation and increased antioxidants). Increased expression of PGC-1α, SIRT3, and SOD2 and decreased expression of Ac-SOD2 correlated with the beneficial outcomes. HPLC revealed protocatechuic acid and cyanidin-3-glucoside as the key components of PRHE. The findings indicate that PRHE effectively protects against the development of DN by retaining mitochondrial redox equilibrium via the regulation of PGC-1α-SIRT3-SOD2 signaling. This study creates an opportunity to develop this agricultural waste into a useful health product for diabetes.