NADPH oxidase-2 inhibitor apocynin attenuates high-fat diet-induced kidney and bladder injury

Objective: This study aimed to evaluate the effects of NADPH oxidase-2 (NOX-2) inhibitor apocynin (APC) on high-fat diet (HFD)- induced renal and bladder injury. Materials and Methods: Wistar albino rats were divided into 4 groups: Control, HFD, HFD+dimetyl sulfoxide (DMSO), and HFD+APC. Rats in HFD, HFD+DMSO, and HFD+APC groups were fed with HFD for sixteen weeks. In the last 4 weeks of the experiment, either DMSO or APC (25 mg/kg, dissolved in DMSO) was applied to the HFD+DMSO or HFD+APC groups. Lipid profiles and leptin values were measured in blood serum. Renal and bladder oxidant/antioxidant parameters, histological changes in the tissues, NOX-2-, nuclear factor kappa B (NF-ĸB)-immunopositive and apoptotic cells were evaluated. Results: At the end of the experiment, leptin, cholesterol, and triglyceride levels were higher and high-density lipoprotein levels were lower in the HFD and HFD+DMSO groups compared to controls. In these experimental groups, an increase in malondialdehyde, 8-hydroxy-deoxyguanosine and myeloperoxidase levels and a decrease in glutathione levels, as well as an increase in collagen, NOX-2 – and NFĸ-B-immunopositive and apoptotic cells were found. Also, a deterioration in kidney and bladder morphology was observed. All these biochemical and histopathological findings improved in the HFD+APC group. Conclusion: High-fed diet causes renal and bladder injury by increasing NOX-2 activity and inflammation via oxidative stress. APC might alleviate tissue injury by inhibiting oxidative stress.