Evaluation of Ginkgo Biloba's potential effects on testis tissue in experimental hypoxia induced during pregnancy

The present study aims to investigate the potential effects of Ginkgo biloba administered during testis development and postnatal periods to the offspring of pregnant rats subjected to chronic hypobaric hypoxia on testis development using immunohistochemical and electron microscopy techniques.For the study purposes, Wistar albino rats on the fifth day of pregnancy were placed in hypoxic chambers filled with a gaseous mixture of O2 10% and N2 90% for 10 days. Three groups of postnatal male rats were formed: the first group served as the control, the second as the hypoxia group and the third as the hypoxia + Ginkgo biloba treatment group. Testis tissues were obtained from the experimental animals on Day 7, 14 and 21, which were stained immunohistochemically with PCNA antibody to study cell proliferation and evaluated using the TUNEL method to determine apoptosis. Changes on the testis thin structure level were examined by using scanning electron microscope. Length of the spermatogenic epithelium was measured in six animals at six points for each group. Statistical analyses were carried out using Shapiro Wilk test, Bonferroni Adjusted Kruskal Wallis and Bonferroni Adjusted Mann Whitney U tests.PCNA immunostaining demonstrated decreased involvement in the hypoxic group compared to the control group, while the extent of involvement was similar between the hypoxic group to which Ginkgo biloba was administered, and the control group.TUNEL assay showed decreased cell proliferation with hypoxia, whereas apoptosis was relatively induced by this condition. Administration of Ginkgo biloba demonstrated protective effects consistent with the control group on Day 21.Electron microscopic studies revealed spermatogenic serial changes and several degenerative alternations, particularly mitochondrial cristae lysis and vacuolization in Leydig cells in the hypoxia group. Leydig cells, which stimulate the development of seminiferous epithelium, were primarily affected by hypoxia, while the thin structure was partially protected in the group to which Ginkgo biloba was administered.Statistical analyses also showed shorter spermatogenic epithelium length in the hypoxic group compared to the control group, whereas a partial increase was achieved after treatment with Ginkgo biloba. In the hypoxic group treated with Ginkgo biloba for 21 days, epithelium length was comparable to that observed in the control group.In conclusion, hypoxia induced during pregnancy adversely affects cell cycle in testis structure of the offspring of experimental animals and also induced Leydig cells activity. On the other hand Ginkgo biloba provides protective effects, particularly with long-term use.