Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2+, the expression and proteolytic activity of calpain in the lens epithelial cells (...Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2+, the expression and proteolytic activity of calpain in the lens epithelial cells (LECs) of H2O2-induced cataract. Methods: Rat lenses were cultured in vitro and cataract was induced by H2O2. The level of intracellular free Ca2+ was measured by fluorescence determination with fura-2/AM. The expression of m-calpain protein in LECs was detected with immunohistochemical method. The proteolytic activity in LECs was measured using a fluorogenic synthetic substrate. Results: There were significant differences of the level of intracellular free Ca2+ (P=0.001, 0.000, 0.000), the expression of m-calpain (P=0.001, 0.000, 0.000) and the proteolytic activity of calpain (P=0.001, 0.000, 0.000) between H2O2-induced and control group at 6, 12 and 24 h, respectively. Conclusions: H2O2 can increase intracellular free Ca2+, then enhance the expression and proteolytic activity of calpain which may play a role in the mechanism of oxidative cataract of rat.展开更多
OBJECTIVE: To detect the expression of basic fibroblast growth factor (bFGF) in human ocular tissues, and to assess the effect of bFGF on the proliferation of human cataract lens epithelial cells (LECs) and its correl...OBJECTIVE: To detect the expression of basic fibroblast growth factor (bFGF) in human ocular tissues, and to assess the effect of bFGF on the proliferation of human cataract lens epithelial cells (LECs) and its correlation with age. METHODS: Enucleated eyes were subjected to immunostaining for bFGF protein. Human cataract LECs were cultured in vitro, and treated with bFGF for 48 hr. Proliferation was estimated by the positive area ratio of proliferating cell nuclear antigen (PCNA) in immunohistochemistry. RESULTS: bFGF protein was found in various human ocular tissues. bFGF stimulated human cataract LEC proliferation, and there was an age-related decrease in responsiveness of human cataract LECs to bFGF (P展开更多
文摘Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2+, the expression and proteolytic activity of calpain in the lens epithelial cells (LECs) of H2O2-induced cataract. Methods: Rat lenses were cultured in vitro and cataract was induced by H2O2. The level of intracellular free Ca2+ was measured by fluorescence determination with fura-2/AM. The expression of m-calpain protein in LECs was detected with immunohistochemical method. The proteolytic activity in LECs was measured using a fluorogenic synthetic substrate. Results: There were significant differences of the level of intracellular free Ca2+ (P=0.001, 0.000, 0.000), the expression of m-calpain (P=0.001, 0.000, 0.000) and the proteolytic activity of calpain (P=0.001, 0.000, 0.000) between H2O2-induced and control group at 6, 12 and 24 h, respectively. Conclusions: H2O2 can increase intracellular free Ca2+, then enhance the expression and proteolytic activity of calpain which may play a role in the mechanism of oxidative cataract of rat.
文摘OBJECTIVE: To detect the expression of basic fibroblast growth factor (bFGF) in human ocular tissues, and to assess the effect of bFGF on the proliferation of human cataract lens epithelial cells (LECs) and its correlation with age. METHODS: Enucleated eyes were subjected to immunostaining for bFGF protein. Human cataract LECs were cultured in vitro, and treated with bFGF for 48 hr. Proliferation was estimated by the positive area ratio of proliferating cell nuclear antigen (PCNA) in immunohistochemistry. RESULTS: bFGF protein was found in various human ocular tissues. bFGF stimulated human cataract LEC proliferation, and there was an age-related decrease in responsiveness of human cataract LECs to bFGF (P