Effect of moderate-intensity aerobic exercise on penile α-SMA and eNOS expression in diabetes mellitus rats model: a non-pharmacological approach to diabetic erectile dysfunction

Background: Diabetes mellitus (DM) is a chronic disease with globally increasing prevalence, significantly impacting quality of life, including erectile dysfunction (ED). Moderate-intensity aerobic exercise has been shown to improve metabolic and cardiovascular parameters, yet limited studies have examined its effect on erectile function. This study aimed to explore the effect of aerobic exercise on the expression of alpha-smooth muscle actin (α-SMA) and endothelial nitric oxide synthase (eNOS) in the penile tissue of diabetic rat models. Methods: This true-experimental study used 24 male Rattus norvegicus (Wistar), aged 12 weeks, randomly assigned to three groups: control (C), diabetic without intervention (NE), and diabetic with aerobic exercise (E). The aerobic exercise was performed for 60 minutes per session, 5 days a week, for 10 weeks. The expression of eNOS and α-SMA in penile tissues was analysed by immunohistochemistry and quantified by Image J Software Version 1.54p. Statistical analysis was performed using SPSS software version 29.0, including tests for homogeneity and normality, followed by one-way ANOVA with LSD or Tukey post hoc tests for normally distributed data, or the Kruskal Wallis test for non-normal distributions. Results: There was no significant difference in eNOS expression among the three groups (p>0.05). However, α-SMA expression showed a significant difference among the three groups (p<0.05). Group E showed a significant increase in α-SMA expression compared to Group NE (p=0.034). Conclusions: Moderate-intensity aerobic exercise improves α-SMA expression in the penile tissue of diabetic rats, contributing to better erectile function. Although it did not affect eNOS expression, this finding supports the potential of exercise-based non-pharmacological therapy for managing ED in diabetic patients.