Effect of IGF-I on the colonizing ability, viability and apoptosis related genes expression in sheep’s spermatogonial stem cells

This study was conducted to evaluate the effect of IGF-I on the number and area of colonies, viability and apoptosis related genes expression in sheep’s spermatogonial stem cells (SSCs). In this study, SSCs at the basal membrane of seminiferous tubules were isolated from testes of Afshari sheep using enzymatic digestion steps. The control group did not receive IGF-I and the other groups received 0.1, 1, 5 and 10 μg/ml IGF-I, respectively. The cells were cultured for 2 weeks and the colonizing abilities were evaluated on the 5th and 14th days of culture. At the end of culturing period, apoptosis status and apoptosis related genes expression (BAX and BCL2) were evaluated. The results showed using 5 and 10 μg/ml IGF-I improved colonizing abilities on the 5th and 14th days compared to the other groups (P≤0.05). The highest viability and lowest apoptosis status was observed in groups received 5 and 10 μg/ml IGF-I (P≤0.05). The highest BCL2 expression and lowest BAX expression was observed in groups received 5 and 10 μg/ml IGF-I (P≤0.05). Therefore, using suitable dose of IGF-I in culture medium could be an effective method to improve the quality and viability of sheep’s SSCs during studying on stem cells.