Effect of dehydroepiandrosterone on meiotic spindle structure and oocyte quality in mice.

OBJECTIVES: Dehydroepiandrosterone (DHEA) has been reported to improve pregnancy chances in women with diminished ovarian reserve (DOR) and to reduce miscarriage rates by 50-80%. This study, therefore, assesses effects of DHEA on number of retrieved oocytes and meiotic spindles. MATERIALS AND METHODS: A randomized, prospective, controlled study was conducted on eight groups, four groups of young mice and four elderly. All young and old groups received different oral doses (35, 50, 75 mg/kg) of DHEA for 3 months. Meiotic spindle assessment was done by immunocytochemical techniques using a confocal laser microscope (Leica TCS-4D). RESULTS: Statistical surveys showed that in control young groups 80% (P=0.0845) and in the old control group 73.3% (P=0.000) of the meiotic spindles have a normal shape and structure; the difference was meaningful. The young with 50 mg/kg of DHEA in 85.4% and the young with 75 mg/kg of DHEA in 84.2% were normal in shape and structure. Statistical analysis showed that the difference was meaningless (P=0.845). The old group with 30 mg/kg of DHEA in 81.1%, the old with 50 mg/kg of DHEA in 83.9%, and the old with 75 mg/kg of DHEA in 79.0% showed normal shape and structure. The meiotic spindle disruption ratio in old mice showed a significant difference (P=0.000) in comparison with others in young groups. Statistical analysis showed that difference between DHEA and control groups is meaningful. But this difference was meaningless between DHEA groups. CONCLUSION: Results showed that DHEA has a positive and improvement effect on the meiotic spindle in old mice.

Study of Tnp1, Tekt1, and Plzf Genes Expression During an in vitro Three-Dimensional Neonatal Male Mice Testis Culture

Background: In vitro spermatogenesis has a long research history beginning in the early 20th century. This organ culture method was therefore abandoned, and alternative cell culture methods were chosen by many researchers. Here, whether Tnp1, Tekt1, and Plzf, which play a crucial role in spermatogenesis, can be expressed during testis organ culture was assessed. Methods: Testes of 10 mouse pups were first removed, and the testis tissue was then separated into smaller pieces of seminiferous tubules. The size of the pieces was arbitrary; approximately 1 mg in weight or 1 mm3 in size when compacted. Afterwards, the testis tissue fragments (1­3) were transferred to the hexahedrons, incubated in a culture incubator and cultured for 12 weeks. Histological assessment and molecular evaluation were carried out at the end of the study. Results: The results showed that the expression of Tekt1 as a mitotic gene in mouse pups decreased significantly (p ≤ 0.05) in comparison to adult mouse testis. Meanwhile, the expression of Tnp1 as a meiotic gene increased significantly (p ≤ 0.05) as compared to neonate mouse testis at the beginning of the culture. The expression of Plzf showed no significant difference during the 12 weeks of culture (p ≥ 0.05). Based on histological study, different types of spermatocytes and post-meiotic stages of germ cells could not be detected. Conclusion: This kind of three-dimensional culture can induce expression of post-meiotic gene, Tnp1, but only at the molecular level and not beyond meiosis.