大豆球蛋白对小肠Ca^(2+)吸收相关酶Ca^(2+)-ATP酶和超氧化物歧化酶活性的影响

Effects of Glycinin on the Activities of Ca^(2+)-ATPase and Superoxide Dismutase in Small Intestine

为探讨大豆球蛋白对小肠内微量元素Ca2+吸收的影响及相关机制。采用自动生化分析仪测定小肠囊内液中Ca2+浓度,并测定小肠囊中段组织中与Ca2+吸收相关的Ca2+-ATP酶和超氧化物歧化酶活性。结果显示,单独应用大豆球蛋白(0.4~1 mg·mL-1)对小肠囊Ca2+吸收无明显影响,但可剂量依赖性抑制小肠粘膜内Ca2+-ATP酶活性,同时剂量依赖性的反馈性诱导增强小肠粘膜内超氧化物歧化酶活性。1 mg·mL-1大豆球蛋白通过抑制Ca2+-ATP酶活性抑制葡萄糖酸钙Ca2+吸收。综上表明,大豆球蛋白通过抑制Ca2+-ATP酶活性阻碍Ca2+的吸收及转运,并可能通过反馈性的增强SOD的活性以减少氧化自由基对粘膜的进一步损伤。

To evaluate the effects and mechanism of glycinin on Ca2＋ absorption in small intestine, the Ca2＋ concentrations of the inner liquid in the everted gut sacs were determined by automatic biochemistry analyzer. Then the homogenized small intestine was applied to evaluate the activities of Ca2＋-ATPase and Superoxide Dismutase （SOD）. The results showed that single usage of glycinin （0.4-1 mg mL-1） to everted gut sacs did not significantly change the Ca2＋ absorption,whereas with dose-dependent inhibitions of Ca2＋-ATPase activities and enhancement of superoxide dismutase activities. But 1 mg mL-1 glycinin could enhance the Ca2＋ absorptions with calcium gluconate addition to culture medium. Our work indicated that glycin inhibited Ca2＋ absorption and transportation by inhibiting the activity of CaE＋-ATPase,and with feedback mode,the activity of SOD was enhanced to resist the damage of oxygen free radicals to intestinal mucosa.