Olatunji L A, Soladoye A O
Department of Physiology, College of Health Sciences, University of Ilorin, P.M.B. 1515, Ilorin, Nigeria.
Afr J Med Med Sci. 2007 Jun;36(2):155-61.
Cardiovascular disorders are the primary causes of morbidity and mortality in patients with diabetes mellitus (DM). Agents that improve lipid profile and reduce oxidative stress have been shown to reduce the ensuing risk factors. In the present study, we investigated whether increased magnesium intake could improve hyperglycaemia, dyslipidaemia, and reduce oxidative stress in alloxan-induced diabetic rats. Male Wistar rats were divided into non-diabetic (ND), diabetic (DM) and diabetic fed on a high magnesium diet (DM-Mg) groups. Plasma concentrations of thiobarbituric acid reactive substances (TBARS) were used as markers of oxidative stress. Plasma levels of ascorbic acid, magnesium and calcium were also determined. Diabetes was induced by injecting alloxan (100 mg/kg B.W). The fasting blood glucose levels were significantly lower in the DM-Mg rats than in the DM rats. Plasma total cholesterol, triglyceride, TBARS levels were significantly higher while plasma HDL-cholesterol, HDL-cholesterol/total cholesterol ratio, ascorbic acid levels were significantly lowered in DM rats compared with the ND rats. Increased intake of magnesium significantly abrogated these alterations. There were no significant differences in the plasma levels of magnesium and calcium between the DM and ND groups. However, plasma levels of magnesium but not calcium were significantly elevated in DM-Mg rats when compared with other groups. In conclusion, these results suggest that diet rich in magnesium could exert cardioprotective effect through reduced plasma total cholesterol, triglyceride, oxidative stress and ameliorated HDL-cholesterol/total cholesterol ratio as well as increased plasma ascorbic acid and magnesium in diabetic rats.
心血管疾病是糖尿病患者发病和死亡的主要原因。已证明能改善血脂状况并降低氧化应激的药物可降低随之而来的风险因素。在本研究中，我们调查了增加镁摄入量是否能改善四氧嘧啶诱导的糖尿病大鼠的高血糖、血脂异常，并降低氧化应激。雄性Wistar大鼠被分为非糖尿病组（ND）、糖尿病组（DM）和高镁饮食喂养的糖尿病组（DM-Mg）。血浆中硫代巴比妥酸反应性物质（TBARS）的浓度用作氧化应激的标志物。还测定了血浆中抗坏血酸、镁和钙的水平。通过注射四氧嘧啶（100mg/kg体重）诱导糖尿病。DM-Mg组大鼠的空腹血糖水平显著低于DM组大鼠。与ND组大鼠相比，DM组大鼠的血浆总胆固醇、甘油三酯、TBARS水平显著升高，而血浆高密度脂蛋白胆固醇、高密度脂蛋白胆固醇/总胆固醇比值、抗坏血酸水平显著降低。增加镁的摄入量可显著消除这些变化。DM组和ND组之间血浆镁和钙水平无显著差异。然而，与其他组相比，DM-Mg组大鼠的血浆镁水平显著升高，而钙水平无显著变化。总之，这些结果表明，富含镁的饮食可通过降低糖尿病大鼠的血浆总胆固醇、甘油三酯、氧化应激，改善高密度脂蛋白胆固醇/总胆固醇比值，以及增加血浆抗坏血酸和镁水平，发挥心脏保护作用。
