Protective Effects of Limonene and a Nano-Liposomal Limonene Formulation Against Chlorfenapyr-Induced Renal Toxicity: Mechanistic Insights into NRF2/HO-1 and NF-κB/COX-2 Signaling, Mitochondrial Dysfunction, and Apoptosis in Rat Kidneys

Abstract

Chlorfenapyr (CFP) is a widely used pesticide associated with nephrotoxicity through oxidative stress, inflammation, and mitochondrial dysfunction. This study investigated the protective effects of limonene (LM) and its nano-liposomal formulation (LM-LNPs) against CFP-induced renal injury in rats. Animals were divided into six groups—control, LM, LM-LNPs, CFP, CFP + LM, and CFP + LM-LNPs—and treated orally for 30 days. CFP exposure resulted in marked renal dysfunction, histopathological and ultrastructural damage, suppression of the NRF2/HO-1/NQO1 antioxidant pathway, depletion of endogenous antioxidants excessive generation of reactive oxygen and nitrogen species, lipid peroxidation products, and DNA damage. These changes were accompanied by activation of NF-κB/COX-2-mediated inflammation, mitochondrial respiratory impairment, disrupted energy metabolism, and induction of apoptosis. Co-treatment with LM significantly ameliorated these alterations, whereas LM-LNPs produced greater improvements in renal function, tissue architecture, redox homeostasis, mitochondrial function, and inflammatory and apoptotic signaling. Immunohistochemical analyses further confirmed enhanced NRF2 expression and reduced NF-κB immunoreactivity in LM-LNP-treated kidneys. Overall, nano-liposomal delivery enhanced the renoprotective efficacy of limonene, highlighting its potential as a therapeutic strategy against pesticide-induced kidney injury.