Consumption of low-protein or high-fat diets during peripubertal age alter spermatozoa, testis and epididymis of pubertal rats.

Since the 1980s, research has linked environmental factors to adult-onset diseases. The DOHaD theory suggests that exposures during development can permanently affect organ function, predisposing individuals to adult diseases. Studies indicate that protein restriction or a high-fat diet (HFD) during this phase impacts adult metabolism since programmed dysfunctions may depend on changes established during puberty, such as the reproductive system. However, there are no studies on the impact of low-protein (LP) or HFD on male testicles during this phase. For this, Male Wistar rats were categorized into three dietary groups: LP (isocaloric low-protein pelletized); HFD; and Control (balanced commercial) until PND 60. This study was approved by the CEUA-UEM. On postnatal day 61, the animals were euthanized for histopathological, sperm count, and oxidative stress assessments in the testis and epididymis. Statistical analyses were conducted following established ethical principles in animal research. The research revealed significant alterations in daily sperm production and transit through the epididymis. Sperm morphology was affected in the experimental groups. Mitochondrial activity increased in the HFD group. Testicular and epididymal histopathology, seminiferous tubule diameter, and germinal epithelium height, as well as the number of Sertoli and Leydig cells, remained unchanged. Stereological analysis revealed tissue remodeling in the epididymis, particularly in the LP group. LP group showed an increase in lipid peroxidation in the oxidative damage test. In conclusion, low-protein and HFD during peripubertal age did not affect postnatal testicular development in rats. However, they impacted sperm quality, potentially affecting fertility and male reproductive system development.