Mechanism of glial cell line-derived neurotrophic factor in proliferation of spermatogonial stem cells

Abstract

Objectives: The aim was to investigate the mechanism of glial cell line-derived neurotrophic factor (GDNF) in the proliferation of spermatogonial stem cells (SSCs) through detecting the expression of GDNF, receptor tyrosine kinases (RTKs), fyn and focal adhesion kinase (FAK) messenger ribonucleic acids (mRNAs) after gene interference. Materials and Methods: Multiple small interfering RNAs (siRNA) of GDNF were designed and constructed to transfect SSCs. The siRNA of GDNF with the highest efficiency was applied and expressions of GDNF, RTKs, fyn and FAK mRNA and the protein were measured with reverse transcription polymerase chain reaction and western blot, respectively. The proliferation and apoptosis of SSCs were measured with enzyme-labeled meter and flow cytometry, respectively. Results: The expression intensity of GDNF mRNA in SSCs of the experimental group and control group was 12.32 ± 1.22% and 54.25 ± 1.34%, respectively; the apoptosis rate was 25.43 ± 1.91% and 5.61 ± 0.16%, respectively; and there was a significant difference between the two groups (P < 0.01). The expression intensity of RTKs, fyn and FAK in the experimental group was 16.24 ± 1.35%, 18.32 ± 1.34%, and 20.04 ± 1.65%, respectively; the expression intensity of RTKs, fyn and FAK in the control group was 45.35 ± 1.37%, 38.37 ± 1.55% and 43.27 ± 1.28%, respectively; there was a significant difference between the two groups (P < 0.01). Conclusion: These results suggest that the constructed positive vector effectively inhibits the expression of GDNF, RTKs, fyn and FAK mRNAs, and the proliferation of SSCs. GDNF plays an important role in the proliferation of SSCs.