Evaluation of the hepatorenal subacute toxicity of polystyrene nanoplastics on immunohistochemical, histopathological, endoplasmic reticulum stress, and biochemical changes: The protective role of ellagic acid

Plastic products are widely used for a variety of purposes. Therefore, exposure to polystyrene nanoplastics (PS-NPs) products may affect the biological systems of humans and other organisms. Ellagic acid (EA) is a naturally occurring flavonoid compound that exhibits antioxidant activities. This study investigated the potential harmful effects of PS-NPs on the liver and kidney, and to determine the molecular and cellular mechanisms related with exposure to PS-NPs 24 male rats were divided randomly and equally into 4 groups; control (distilled water), PS-NPs (15 mg/kg/day) exposed group, EA (35 mg/kg/day) exposed group and PS-NPs plus EA exposed group via orally using gavage for 28 days. The application of PS-NPs for 28 days led to a decrease in Nrf2 levels and the antioxidant content (SOD, CAT, GPx, and GST) liver and kidney tissues, while the MDA level, which is an indicator of cellular lipid peroxidation, increased. Additionally, changes were observed in serum indicators such as ALT, AST, LDH, urea and creatinine. Similarly, 8-OHdG, NF-κB, IL-1β levels, TNF-α and caspase-3 expression increased. Histopathological changes were observed in liver and kidney tissues, along with an increase in ER stress (HSP70, HSP90, GRP78, PERK, and CHOP). The combination of EA treatment and PS-NPs led to a reduction in PS-NPs-induced hepatic and renal toxicity and an enhancement in the parameters that were investigated.