Three-dimensional morphological analysis of spermatogenesis in aged mouse testes

Area of Science:

• Reproductive Biology
• Gerontology
• Cell Biology

Background:

• Spermatogenesis, the process of sperm production, naturally declines with advancing age.
• Understanding age-related changes in spermatogenesis is crucial for addressing male infertility.

Purpose of the Study:

• To investigate age-related and region-specific alterations in spermatogenesis using a 3D reconstruction of mouse seminiferous tubules.
• To examine changes in the seminiferous epithelium and spermatogenic waves over time.

Main Methods:

• 3D reconstruction of seminiferous tubules from serial sections of 12 mice aged 12 to 30 months.
• Analysis of age-related and region-specific changes in the seminiferous epithelium and spermatogenic waves.
• Assessment of spermatogenesis impairment via Sertoli cell vacuole formation.

Main Results:

• Seminiferous tubule structure (number, branching, length) remained unchanged with age.
• Age-related alterations in spermatogenesis, marked by Sertoli cell vacuole formation, were evident by 12 months.
• Impaired spermatogenesis increased by 24 months and was localized near the rete testis and testis center.
• Spermatogenic waves progressively shortened with age.

Conclusions:

• Aging significantly impacts spermatogenesis, leading to impaired sperm production and altered spermatogenic waves.
• Region-specific alterations within the seminiferous tubules contribute to age-related decline.
• These findings provide a foundation for understanding age-related male infertility and developing interventions.