¹Xizang Agriculture and Animal Husbandry University, College of Animal Science, Linzhi 860000, Xizang, P. R. CHINA
²Key Laboratory for Prevention and Control of Hydatid Disease in Xizang (Co-constructed by Ministry and Province), Ministry of Agriculture and Rural Affairs,College of Animal Science, Xizang Agricultural and Animal Husbandry University, Linzhi 860000, Xizang, P. R. CHINA DOI : 10.9775/kvfd.2026.37003 Both copper sulfate (CuSO₄) and polystyrene microplastics (PS-MPs) exhibit toxic effects on the male reproductive system. Notably, PS-MPs can adsorb copper ions, making their combined pollution-induced reproductive toxicity and underlying mechanisms urgent to clarify. This study aimed to investigate the toxic effects of CuSO₄ and PS-MPs co-exposure on sperm quality and testicular tissue in male mice, and to determine potential synergism, thereby providing a basis for assessing reproductive health risks. Male mice were randomly divided into control, CuSO₄, PS-MPs, and combined exposure groups, with continuous intragastric administration for 30 days. Sperm parameters, testicular histopathology, cell apoptosis, and apoptosis-related protein expressions [Bcl-2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2), cysteinyl aspartate specific proteinase-3 (Caspase-3), tumor protein p53 (p53)] were detected. Results showed that combined exposure most significantly inhibited body weight gain (P<0.05). Compared with single exposure, the combined group exhibited more severe sperm quality deterioration, severe testicular histopathological lesions, and a significant increase in Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells (P<0.05 or P<0.01). Western blot analysis confirmed upregulated expressions of Bax, Caspase-3, and p53, and downregulated Bcl-2 in the combined group, indicating activation of the apoptotic pathway. In conclusion, CuSO₄ and PS-MPs have aggravated toxic effects on the male reproductive system, and the mechanism involves the activation of apoptotic signaling. Keywords : Combined exposure, CuSO₄, Male reproductive toxicity, PS-MPs, Sperm quality