Niosomal l-carnitine and quercetin improve sperm quality and testicular function in atrazine-induced reproductive toxicity in rats.

Atrazine (ATZ), a frequently employed herbicide, is classified as one of the environmental pollutants that play a pivotal role in progression of male infertility. L-carnitine (LC) and quercetin (QT) possess antioxidant properties, rendering them viable additional treatments for male infertility. Additionally, specialized drug delivery systems, such as niosomes, enhance the distribution of hydrophilic pharmaceuticals. This study aimed to investigate the ameliorative potential of LC and QT, administered in conventional and niosomal formulations, against ATZ-induced testicular dysfunction in adult male albino rats. Thirty rats were randomly assigned to six experimental groups: control, ATZ, ATZ + LC, ATZ + LC-loaded niosomes (LCLN), ATZ + QT, and ATZ + QT-loaded niosomes (QTLN). Treatments were administered orally for 56 consecutive days. Biochemical analyses, sperm evaluations, gene expression assessments, and histopathological measures were conducted. ATZ exposure significantly decreased absolute and relative seminal vesicle weights, impaired sperm motility, viability, morphology and count, and reduced circulating testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) concentrations. Moreover, ATZ markedly elevated malondialdehyde levels, suppressed the activities of endogenous antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase), and downregulated the transcription of key steroidogenic genes (HSD3B, StAR and CYP11A1). Histopathological assessment further revealed pronounced degenerative changes in the testes, epididymis, seminal vesicles, and prostate. Co-administration of LC or QT, particularly in niosomal formulations, significantly attenuated these deleterious effects. They restored sperm quality, re-established redox homeostasis, normalized steroidogenic gene expression, and preserved the structural integrity of reproductive tissues. In conclusion, niosomal formulations of LC and QT confer superior protective efficacy against ATZ-induced testicular toxicity compared to their conventional counterparts, underscoring their therapeutic potential as targeted interventions against environmental toxicants.