The Effect Of 1α,25-（OH）₂D₃ On Sheep Testicular Cells

[Objective] Vitamin D is a steroid hormone with a broad range of functions, it regulates lots of physiological functions, such as calcium homeostasis, bone metabolism, cell differentiation and proliferation, with the help of vitamin D recepter (VDR). Recently, researchers have found that VDR also exists in the reproductive system of male animals, therefore, many studies about the effect of vitamin D on male reproductive function have been launched. But the direct effect of bioactive vitamin D (1α,25-(OH)2D3) on testicular cells is unclear. Therefore, the objectives of this study were to investigate the effect of 1α,25-(OH)2D3 on cell viability, proliferation, apoptosis, cAMP, glycometabolism and antioxida-tion of sheep testicular total cells; investigate the effect of 1α,25-(OH)2D3 on cell viability, testosterone production and expression of testosterone production-related genes of Leydig cells; investigate the effect of 1α,25-(OH)2D3 on ABP production and phagocytosis of Sertoli cells.[Method] After cultured with different concentration of 1α,25-(OH)2D3 (0 nM,1 nM,10 nM,100 nM), the cell viability of testicular total cells and Leydig cells was tested by CCK-8; the proliferation of testicular total cells was determined by cell counting; the apoptosi of testicular total cells was determined by apoptosis fluorescence staining and expression analyze of apoptosi related genes; the cAMP production of testicular total cells, testosterone production of Leydig cells and ABP production of Sertoli cells were measured by Elisa; the glycometabolism-related enzymes and antioxidation-related enzymes activities were tested by colorimetry; the expression of testosterone production-related genes were measured by Real-time PCR; the phagocytosis of Sertoli cells was determined by oil red o staining and triglyceride and cholesterol analyze.[Result] The results showed that 1α,25-(OH)2D3 increased the cell viability, intracellular cAMP concentration, glucose absorption, lactic acid production, hexokinase activity, pyruvic acid production, lactic dehydrogenase activity, citrate synthase activity, succinodehydrogenase activity, total antioxidant capacity, catalase activity, superoxide dismutase activity of sheep testicular total cells(P<0.05/P<0.01); however, the effects of 1α,25-(OH)2D3 on cell proliferation, apoptosis genes (p53, box, bcl-2) expression, pyruvate kinase activity, glutathion peroxidase activity and glutathione S transferase activity of sheep testicular total cells were non-existent. The results also showed that 1α,25-(OH)2D3 increased the cell viability and LH-induced testosterone production of sheep Leydig cells, increased the expression of testosterone biosynthesis genes (StAR,3β-HSD, CYP17a) (P<0.05/P<0.01); however, there were no effect of 1α,25-(OH)2D3 on the expression of testosterone biosynthesis genes (P450scc and 17βHSD). For sheep Sertoli cells, the results showed that 1α,25-(OH)2D3 increased the ABP production of sheep Sertoli cells (P<0.05). However, the effect of 1α,25-(OH)2D3 on phagocytosis of sheep Sertoli cells was non-existent.[Conclusion] 1α,25-(OH)2D3 increased the cell viability, intracellular cAMP concentration, the abilities of glycometabolism and antioxidation of sheep testicular total cells, however, the effect of 1α,25-(OH)2D3 on proliferation and apoptosis of sheep testicular total cell were non-existent. 1α,25-(OH)2D3 increased the cell viability of Leydig cells, and increased LH-induced testosterone production by improving the expression of testosterone production-related genes (StAR,3β-HSD, CYP17d). 1α,25-(OH)2D3 increased the ABP production of sheep Sertoli cells. However, the effect of 1α,25-(OH)2D3 on phagocytosis of sheep Sertoli cells was non-existent.