Upregulation of Integrin-α6 and Integrin-β1 Gene Expressions in Mouse Spermatogonial Stem Cells after Continues and Pulsed Low Intensity Ultrasound Stimulation

OBJECTIVE: low intensity ultrasound (continues and pulsed) is a form of energy. Spermatogonial stem cells (SSCs) are at the base of male fertility. This study investigated the effects of low intensity ultrasound stimulation (LIUS) and low intensity pulsed ultrasound stimulation (LIUPS) on the expression of germ cell-specific and pluripotency genes in SSCs in vitro. MATERIALS AND METHODS: In this experimental study, isolated SSCs from neonatal male mice were cultured in Dulbecco’s Modified Eagle’s Medium (DMEM) with 10% fetal bovine serum (FBS). In addition, to confirm identification of SSCs, PLZF protein was detected positively in SSCs derived colonies. SSCs were stimulated by LIUS and LIUPS for 5 days, followed by assessment of expression of integrin-α6 (Itga6) and β1 (Itgβ1), as two germ cell-specific genes, and Oct- 4, as a pluripotency gene, on day 21st by quantitive reverse transcriptase-polymerase chain reaction (qRT-PCR). To investigate the proliferation rate and colonization of SSCs in different groups, counting whole number of the cells and colonies as well as analysis of the respective diameters were performed on days 7(th), 14(th) and 21(st). Data was analyzed by ANOVA test. RESULTS: LIUS and LIUPS treatment of mouse SSCs increased expression of Itga6 and Itgβ1 genes in the experimental groups, compared to the control group (P<0.05), whereas there was no significant difference between the groups, regarding the expression of Oct-4 gene. These treatments maintained survival rate, while they increased proliferation rate and colonization of SSCs during the first week of culture. However, within the second week, proliferation rate and colonization were decreased in the experimental groups. CONCLUSION: These results suggested that LIUS and LIUPS treatment had good effect on SSCs proliferation and colonization, based on the gene-specific marker expression during 21 days culture in vitro.