Ren Hongmei, Ghebremeskel Kebreab, Okpala Iheanyi, Lee Ava, Ibegbulam Obike, Crawford Michael
Institute of Brain Chemistry and Human Nutrition, London Metropolitan University, London, United Kingdom.
Int J Vitam Nutr Res. 2008 May;78(3):139-47. doi: 10.1024/0300-9831.78.3.139.
In previous studies, we found that homozygous sickle cell (HbSS) patients, compared with their healthy (HbAA) counterparts, had reduced levels of the omega-3 fatty acids, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, in red cells, platelets, and mononuclear cells. These differences were not due to lower intake of the two fatty acids. We have investigated whether reduced antioxidant status in the patients could help explain the observed phenomenon. Blood specimens previously obtained for fatty acid study from Nigerian (26 HbSS and 30 HbAA) and British (30 HbSS, 9 sickle cell-hemoglobin C/HbSC, and 15 HbAA) subjects were analyzed for antioxidant status. The Nigerian HbSS patients compared with the controls had lower plasma retinol, alpha-tocopherol, and beta-carotene concentrations (p < 0.005) and reduced activity of red cell Cu/Zn-superoxide dismutase (Cu/Zn-SOD) (p < 0.05). Similarly, the British HbSS group had reduced concentrations of plasma alpha-tocopherol (p < 0.005), and activities of red cell Cu/Zn-superoxide dismutase (p < 0.05) and Se-glutathione peroxidase (Se-GPx) (p < 0.005) than the controls. In addition, the British patients in comparison with those who had HbSC, a mild form of the disease, had lower alpha-tocopherol than that of the HbAA controls (p < 0.005). In the British sickle cell patients, there was a positive correlation between red cell ethanolamine phosphoglyceride (EPG) DHA and Cu/Zn-SOD activity (r = 0.700, p < 0.05), choline phosphoglyceride (CPG) DHA and Se-GPx activity (r = 0.605, p < 0.05), and CPG EPA and Se-GPx activity (r = 0.558, p > 0.05). Similarly, the percent DHA in red cell EPG was positively related with the activity of Se-GPx in the patients with HbSC (r = 0.674, p < 0.05). These findings suggest that the lower levels of membrane EPA and DHA in blood cells of the HbSS patients could be due to peroxidation resulting from a compromised antioxidant competence.
在先前的研究中，我们发现，与健康（HbAA）对照者相比，纯合子镰状细胞（HbSS）患者红细胞、血小板和单核细胞中的ω-3脂肪酸二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）水平降低。这些差异并非由于这两种脂肪酸的摄入量较低。我们研究了患者抗氧化状态降低是否有助于解释所观察到的现象。对先前从尼日利亚（26例HbSS和30例HbAA）和英国（30例HbSS、9例镰状细胞-血红蛋白C/HbSC和15例HbAA）受试者采集的用于脂肪酸研究的血液标本进行了抗氧化状态分析。与对照组相比，尼日利亚HbSS患者的血浆视黄醇、α-生育酚和β-胡萝卜素浓度较低（p<0.005），红细胞铜/锌超氧化物歧化酶（Cu/Zn-SOD）活性降低（p<0.05）。同样，英国HbSS组的血浆α-生育酚浓度（p<0.005）、红细胞铜/锌超氧化物歧化酶活性（p<0.05）和硒谷胱甘肽过氧化物酶（Se-GPx）活性（p<0.005）均低于对照组。此外，与患有轻度疾病形式HbSC的患者相比，英国患者的α-生育酚低于HbAA对照组（p<0.005）。在英国镰状细胞患者中，红细胞乙醇胺磷酸甘油酯（EPG）DHA与Cu/Zn-SOD活性之间存在正相关（r = 0.700，p<0.05），胆碱磷酸甘油酯（CPG）DHA与Se-GPx活性之间存在正相关（r = 0.605，p<0.05），CPG EPA与Se-GPx活性之间存在正相关（r = 0.558，p>0.05）。同样，HbSC患者红细胞EPG中的DHA百分比与Se-GPx活性呈正相关（r = 0.674，p<0.05）。这些发现表明，HbSS患者血细胞中膜EPA和DHA水平较低可能是由于抗氧化能力受损导致的过氧化作用。
