Comparative proteomic analysis of heat stress proteins associated with rat sperm maturation

Heat stress is demonstrated to have an effect on the function of the male testis, however, limited information has been reported on its effects on sperm maturation. In the present study, a comparative proteomic analysis was performed on the rat caput epididymal fluids responsible for sperm maturation, to identify key heat‑stress‑associated sperm maturation proteins. The results demonstrated 21 proteins corresponding to 29 differential protein spots, including 10 downregulated and 11 upregulated proteins in the heat treatment group. Functional analysis demonstrated that these proteins were primarily involved in enriched reproduction and antioxidant activity. Analysis of western blot and immunohistochemical analysis demonstrated that the expression of antioxidant proteins peroxiredoxin 6 and clusterin were downregulated, and the expression of superoxide dismutase upregulated, in the heat treatment group. Morphological and TUNEL experiments demonstrated that altered nucleus activity occurred in the caput epididymis. The study provided, to the best of our knowledge, novel information for studies on the biological functions of the epididymis and sperm maturation.