Effects of Quercetin on Palladium Chloride-Induced Endoplasmic Reticulum Stress, Inflammation, Oxidative Stress, and Apoptosis in Hepatorenal Tissues

To understand the potential hazards of palladium particles dispersed in the environment, comprehensive toxicological studies are required. Quercetin (Que) is a natural flavonoid compound with antioxidant properties. This study was conducted to investigate the potential protective effects of Que (30 mg/kg bw) usage against oxidative stress, apoptosis, inflammation, and endoplasmic reticulum (ER) stress damage in palladium chloride (PdCl2) (8 mg/kg bw)-induced hepatorenal toxicity in rats. As a result of 28 days of PdCl2 application, antioxidant capacity (SOD, CAT, GPx, and GST) in hepatorenal tissues decreased, and the MDA level, which is a marker of lipid peroxidation, increased. In addition, changes were determined in markers such as ALT, AST, LDH, urea, and creatinine in serum. Similarly, PON-1 and AChE activities decreased and NO, 8-OHdG, IL-1β, and IL-6 levels and TNF-α expression increased. Due to PdCl2 exposure, cytoprotective transcription factor Nrf2 expression decreased and caspase-3 expression increased. Along with the increase in ER stress (HSP70, HSP90, GRP78, and CHOP) induced by PdCl2, a decrease in aquaporin 1 and nephrin expressions was observed in renal tissues due to histopathological changes in hepatorenal tissues. Que treatment together with PdCl2 reduced PdCl2-induced hepatorenal toxicity and provided improvement in the investigated parameters.