Hypoxia reduces the proliferation and occludin expression of primary sertoli cells / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the effect of hypoxia on the proliferation and occludin expression of primary rat Sertoli</p><p><b>METHODS</b>We constructed a primary Sertoli cell system by two-step enzymatic digestion in 18 -22 days old Wistar rats and identified it by oil red O and immunofluorescence methods. We randomly divided the Sertoli cells into five groups to be cultured in oxygen at the concentrations of 20%, 15%, 10%, 5% and 1%, respectively, for 6, 12, 24, 48 and 72 hours. We detected the proliferation of the Sertoli cells by CCK-8 assay, determined the expression of occludin by Western blot, and analyzed the differences among the five groups.</p><p><b>RESULTS</b>Oil red O staining revealed red lipid droplets in the cytoplasm of the Sertoli cells, and immunofluorescence showed the positive expression of the FasL protein, with the purity of Sertoli cells over 95% in vitro. Compared with the 20% normoxic group, the proliferation of the Sertoli cells was gradually reduced in the 15% and 10% hypoxia groups, and significantly declined in the 5% and 1% groups (P < 0.01). At 12 hours, the expression of occludin began to decrease with the prolonging of time and reduction of oxygen concentration (P < 0.01).</p><p><b>CONCLUSION</b>Hypoxia suppresses the proliferation of Sertoli cells and reduces the expression of occludin. It could be inferred that hypoxia could damage the integrity of blood-testis barrier and spermatogenesis of the testis.</p>

High temperature reduces the proliferation of and occludin expression in rat Sertoli cells in vitro / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the action mechanisms of temperature in male infertility or subfertility by observing the effects of different temperatures on the proliferation of and occludin (OCLN) expression in rat Sertoli cells in vitro.</p><p><b>METHODS</b>We isolated Sertoli cells from the testis of male Wistar rats, and performed oil red O staining and immunohistochemistry to identify their FasL. We cultured the Sertoli cells at 34 degrees C (control group) and at 35, 36, 37, 38 and 39 degrees C (experimental groups) for 4 days. Then we measured their proliferation by CCK-8 assay, observed their morphology and structure by hematoxylin-eosin staining, and determined their OCLN expression level by Western blotting and immunofluorescence.</p><p><b>RESULTS</b>The purity of the isolated Sertoli cells was (96.20 +/- 1.95)%. CCK-8 assay indicated that the proliferation of the Sertoli cells was increased between 34 and 36 degrees C, and decreased at 36-39 degrees C. The pyknotic nuclei and fragmentation of the Sertoli cells were more obvious at > 36 degrees C. Western blot and immunofluorescence showed the highest level of OCLN expression at 36 degrees C, which, however, decreased while the temperature rose above 36 degrees C (P < 0. 01).</p><p><b>CONCLUSION</b>High temperature (> 36 degrees C) inhibited the proliferation of rat Sertoli cells in vitro, and decreased the expression of OCLN, which suggests that a higher temperature above 36 degrees C may reduce male fertility by affecting the proliferation of Sertoli cells and integrity of the tight junction among Sertoli cells or Sertoli cells and other cells.</p>