Department of Biophysics, Panjab University, Chandigarh, 160014, India.
Department of Hematology, Postgraduate Institute of Medical Education and Research, (PGIMER), Chandigarh, India.
Biol Trace Elem Res. 2019 Jun;189(2):490-500. doi: 10.1007/s12011-018-1483-y. Epub 2018 Aug 27.
Selenium (Se), an essential trace element and potent nutritional antioxidant, exerts its biological effects through incorporation into selenoproteins like glutathione peroxidase (GPx). Modest decrement in the levels of GPx could be partly responsible for peroxidation of RBCs, which results into hemolytic anemia. Therefore, it is hypothesized that dietary Se, as selenoproteins (GPx), can maintain the homeostasis in RBCs and regulate the erythropoiesis by preventing oxidative stress-mediated hemolysis. Se-deficient (0.01 ppm), Se-adequate (0.1 ppm sodium selenite), and Se-supplemented (0.5 ppm sodium selenite) status were created in Balb/c mice by feeding yeast-based diets for 8 weeks and established by measuring Se levels in plasma and activities, expressions of Se-dependent selenoproteins. Fifty percent of mice from each differential Se group were treated with phenylhydrazine (PHZ, 20 mg/kg, i.p.) to induce hemolytic anemia. Results indicated that PHZ-treated Se-deficient animals demonstrated increased hemolysis, abnormal RBC morphology, increase in Heinz bodies and reticulocytes, and denaturation of hemoglobin to globin precipitates and methemoglobin. Se supplementation protected against these hemolytic changes and makes RBCs less fragile. These findings were consistent with dietary Se concentration-dependent changes in activity and expression of GPx indicating that ROS-mediated oxidative stress is integral to hemolysis. Protective effects of Se supplementation against increased levels of ROS, protein carbonyls, and peroxide damage to membrane lipids and enzymatic antioxidants validated these observations. In conclusion, dietary Se supplementation protected the RBCs against hemolysis by mitigating ROS-mediated oxidative stress.
硒(Se)是一种必需的微量元素和有效的营养抗氧化剂,通过与谷胱甘肽过氧化物酶(GPx)等硒蛋白结合发挥其生物学作用。GPx 水平的适度降低可能部分导致 RBC 过氧化,从而导致溶血性贫血。因此,有人假设膳食硒(如硒蛋白(GPx))可以通过防止氧化应激介导的溶血来维持 RBC 内稳态并调节红细胞生成。通过用基于酵母的饮食喂养 8 周,在 Balb/c 小鼠中建立了硒缺乏(0.01 ppm)、硒适量(0.1 ppm 亚硒酸钠)和硒补充(0.5 ppm 亚硒酸钠)状态,并通过测量血浆和活性中的硒水平来确定硒状态。来自每个差异硒组的 50%的小鼠用苯肼(PHZ,20 mg/kg,ip)处理以诱导溶血性贫血。结果表明,PHZ 处理的硒缺乏动物表现出溶血增加、RBC 形态异常、海因茨体和网织红细胞增加以及血红蛋白变性为珠蛋白沉淀和高铁血红蛋白。硒补充可防止这些溶血变化并使 RBC 不易破裂。这些发现与 GPx 活性和表达随膳食硒浓度的变化一致,表明 ROS 介导的氧化应激是溶血的关键。硒补充对 ROS、蛋白质羰基和过氧化损伤膜脂质和酶抗氧化剂水平增加的保护作用验证了这些观察结果。总之,膳食硒补充通过减轻 ROS 介导的氧化应激来保护 RBC 免受溶血。