The Role of Brain-Derived Neurotrophic Factor in Male Subfertility: A Molecular Investigation

Abstract

Male subfertility represents a significant and escalating global health concern with profound implications for couples worldwide. Emerging evidence has highlighted the potential interplay between several key factors in male reproductive health, with particular emphasis on the interrelationships between Brain-Derived Neurotrophic Factor (BDNF), testosterone, zinc homeostasis, and inflammatory processes. These factors are increasingly recognized as critical modulators of reproductive function. This study is designed to investigate the specific role of BDNF in subfertile males and to elucidate its potential implications for key reproductive pathways, including spermatogenesis, steroidogenesis, and overall reproductive capacity. Twenty-two subfertile male patients, aged between 29 and 40 years, were recruited from the infertility clinic at Al-Madina Fertility Center, Alexandria. Comprehensive evaluations included semen analysis, hormonal assessments, and molecular analyses of BDNF levels in serum and seminal plasma. Significantly lower serum and seminal plasma BDNF levels were observed in all patient categories compared to the control group (n=22 fertile males, p ≤ 0.001). BDNF levels correlated positively with sperm motility and total sperm count (r= 0.530, p < 0.012 and r = 0.449, p < 0.045). Furthermore, a noteworthy inverse relationship was found between BDNF levels and the proportion of abnormal sperm morphology (r=-0.488, p < 0.039). This study demonstrates that reduced levels of BDNF in subfertile males are associated with impaired semen quality. The findings suggest BDNF's role in male subfertility. Further research is needed to clarify its mechanisms and explore therapeutic potential, ultimately leading to more effective and personalized interventions for men facing challenges with fertility.