Effect Of C-jun On Basic Proliferation Of Piglet's Leydig Cells In Vitro

Leydig Cells are the main excreting cells which apply multiple enzymes to produce testosterone from cholesterol. The testosterone secretion is regulated by many factors, such as gonadotrophins, growth factors. In fact, several studies indicated that these factors regulate testosterone secretion through adjusting the related proto-oncogenes. Anyway, it's ultimately decided by the capacity of Leydig Cells'testosterone synthesis, including the number of Leydig Cells and capacity of single cell. The former has relation to proliferation and apoptosis, the latter is determined by the activity of testosterone synthesis related enzymes. As one of proto-oncogenes in process of testosterone synthesis, c-jun can promote the testosterone serection. It's unknown whether c-jun can affect the number of Leydig Cells or it can influence the activity of related enzymes. Also, it's reported that c-jun has positive contribution to proliferation. Therefore, this study was aimed to research the effect of c-jun on basic proliferation of piglet's Leydig cells in vitro, to approach the mechanism of c-jun in testosterone synthesis.Leydig Cells were isolated from 3-weeks-old piglets'testis. Its activity, purity and function were qualified before being cultured in vitro. Then they were respectively treated with 0.125,0.25, 0.5,1 and 2μmol/L c-junASODNs, and the expression of c-jun mRNA were detected by FQ-PCR. To study the effect of c-jun on basic proliferation of piglet's Leydig Cells, growth inhibition ratio of Leydig Cells were detected by MTT method and cell cycle phase distribution were examined by flow cytometer analysis, after having been treated with c-junASODNs.Through activity, purity and function evaluation, cells whose activity was over 95%, purity was over 90% and function was very well were chosed to be cultured in vitro. The result of FQ-PCR assays showed that c-jun mRNA expression decreased with the rasing of c-junASODNs concentration.Only 0.125μmol/L c-jun ASODNs could decrease the expression of c-jun gene predominancely (p<0.01). And the expression no longer went down when the concentration up to 1μmol/L. Through MTT analysis, it's found that c-jun ASODNs could significantly inhibit the growth of Leydig Cells (p＜0.01). There has positive correlation between c-jun ASODNs concentration and growth inhibition ratio of Leydig Cells (r=0.8966). After being detected by flow cytometer, we found that the number of Leydig Cells in S phase depressed significantly and that of G0/G1 phase increased aobviously (p＜0.01), after treated with 0.125μmol/L c-jun ASODNs. Compared with the control group, the percentage of Go/G1 phase cell numbers respectively raised 5.78%,11.36%, 16.73%,22.25% and 23.36%. In summary, conclusions were as follows:(1) c-jun ASODNs could inhibit the expression of c-jun mRNA effectively.(2) c-jun ASODNs could low down the growth of Leydig Cells dose-independently.(3) c-jun ASODNs could block cells cycle of Leydig Cells on G0/G1 phase.