Evaluation of the efficacy of icariin against heat stress-induced spermatogenic dysfunction in the testes of dogs.

Abstract

INTRODUCTION: This study examines the detrimental effects of high-temperature environments on canine testicular function and reproductive health, and investigates the potential of, particularly its active component icariin, in alleviating these effects and improving testicular function. METHODS: A completely randomized single-factor design was employed, involving 24 adult male Beagle dogs (9.82&#x202f;&#xb1;&#x202f;0.73&#x202f;kg) assigned randomly to four treatment groups, with six dogs in each group. The groups included a negative control group ("Control"), a positive control group exposed to testicular heat stress ("Model"), and two icariin-treated groups receiving daily doses of 0.5&#x202f;g/kg (Icariin-L) and 1.0&#x202f;g/kg (Icariin-H), respectively. All groups, except the negative control, underwent a testicular heat stress model to induce damage and assess the effects of icariin on sperm quality, testicular function, hormone levels, protein expression, and testicular histological changes. RESULTS: Icariin supplementation improved sperm quality under heat stress, as indicated by increased total sperm count and motility, along with a reduction in sperm malformation rate (&#x202f;<&#x202f;0.01). It also restored adenosine triphosphate (ATPase) activities (Na-K-ATPase, Mg-ATPase, and Ca-ATPase) and serum hormone levels (,, and) (&#x202f;<&#x202f;0.01). Western blot analysis revealed that icariin upregulated steroidogenic proteins (,, and) and the tight junction protein(&#x202f;<&#x202f;0.01), while downregulating theexpression (a key regulator of mitochondrial apoptosis) and enhancing theexpression (a major anti-apoptotic factor in thefamily) (&#x202f;<&#x202f;0.01). Histological assessments demonstrated that icariin mitigated heat-induced damage to seminiferous tubules, epithelial thinning, and spermatogonia degeneration. Furthermore, molecular docking analysis confirmed a strong binding affinity between icariin and, mediated by hydrogen bonding and hydrophobic interactions. CONCLUSION: These findings suggest that icariin may alleviate testicular heat stress by modulating testosterone synthesis, enhancing ATPase function, restoring blood-testis barrier integrity, and inhibiting apoptosis. The dose-dependent efficacy (1.0&#x202f;g/kg&#x202f;>&#x202f;0.5&#x202f;g/kg) supports the potential of icariin as a possible therapeutic agent for improving reproductive health in dogs exposed to high-temperature environments.