title: Effect of different zinc sources and levels on inhibition of the apoptosis induced by glucocorticoid of thymocytes in vitro.
abstract: This experiment was conducted to investigate the effects of zinc sulfate and zinc methionine (Zn-Met) and their levels on apoptosis induced by glucocorticoid of thymocytes and the possible mechanism. Dexamethasone was used to make the apoptosis model of thymocytes; zinc sulfate and zinc methionine were supplemented to the medium at levels of 0, 50, 100, 500, and 1000 microM. The activity of cells, Cu,Zn superoxide dismutase (Cu,Zn-SOD), DNA ladder pattern, intracellular calcium concentration, and the percentage of apoptosis nuclei were determined. Both ZnSO4 and Zn-Met could modulate apoptosis; they inhibited apoptosis and decreased DNA fragmentation. The regulation was concentration dependent. At levels of 50 and 100 microM, the effect of Zn-Met on inhibiting apoptosis was less efficient than that of ZnSO4 (p<0.05), but the activity of the cells cultured with Zn-Met was higher than those cultured with ZnSO4; they showed no difference in modulating apoptosis when added at levels of 500 and 1000 microM to the medium (p>0.05). Intracellular calcium concentrations of cells cultured with Zn-Met were higher than those cultured with ZnSO4 at the same levels. Zinc supplementation decreased the concentration of intracellular calcium significantly (p<0.05) and increased the activity of Cu,Zn-SOD in the extract of the cells (p<0.05). Both zinc sulfate and Zn-Met could modulate apoptosis of thymocytes induced by glucocorticoid; the mechanism might involve the exchange of intracellular calcium, the redox of cells, and the two forms of zinc might go different ways in the regulations.
authors: Department of Animal Nutrition, School of Food Science and Technology, Southern Yangtze University, Wuxi, Jiangsu Province, People's Republic of China.
authors: Yu
authors: Y
authors: Ze-peng
authors: Le
authors: L
authors: Guo-wei
authors: Huang
authors: H
authors: Hong-yu
authors: Wei
authors: W
authors: Yun-yu
authors: Shi
authors: S
authors: Yong-hui
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis; D002118:Calcium / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D004396:Coloring Agents / Q000494:pharmacology; D004247:DNA / Q000737:chemistry; D053938:DNA Fragmentation; D003907:Dexamethasone / Q000494:pharmacology; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D005938:Glucocorticoids / Q000378:metabolism*; D066298:In Vitro Techniques; D051379:Mice; D008813:Mice, Inbred ICR; D010084:Oxidation-Reduction; D013482:Superoxide Dismutase / Q000378:metabolism; D013778:Tetrazolium Salts / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism*; D013997:Time Factors; D015032:Zinc / Q000378:metabolism / Q000494:pharmacology*; D017967:Zinc Compounds / Q000378:metabolism; D019287:Zinc Sulfate / Q000378:metabolism
chemical_list: D000975:Antioxidants; D004396:Coloring Agents; D005938:Glucocorticoids; D013778:Tetrazolium Salts; D013844:Thiazoles; D017967:Zinc Compounds; D019287:Zinc Sulfate; D003907:Dexamethasone; D004247:DNA; D013482:Superoxide Dismutase; C022616:thiazolyl blue; D015032:Zinc; D002118:Calcium