Konukoglu Dildar, Serin Ozden, Turhan Mehtap Sultan
Department of Biochemistry, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey.
Arch Med Res. 2006 Jul;37(5):602-6. doi: 10.1016/j.arcmed.2005.12.002.
Recent evidence suggested that leptin-induced oxidative stress in human endothelial cells in vivo and increased oxidative stress in human essential hypertension may further contribute to both the development of atherosclerosis and other cardiovascular diseases. We investigated the association of plasma leptin levels with plasma lipid peroxidation and nitric oxide metabolites (NOx) in obese hypertensive atherosclerosis model.
Plasma leptin, lipid peroxidation and NOx levels were determined in age-matched non-obese normotensive female subjects (n = 30), obese normotensive female subjects (n = 45), and obese hypertensive female subjects (n = 50). Plasma leptin levels were determined by immunoradiometric method. Lipid peroxidation was determined as thiobarbituric acid reactive substances (TBARS) using spectrophotometric method. NOx levels were determined using enzymatic method.
We found that plasma leptin and TBARS levels were increased in obesity, and obese hypertensives have significantly higher plasma leptin and TBARS levels than obese normotensives (p <0.001 and p <0.001). Obese hypertensives have significantly lower plasma NOx levels than obese normotensives (p <0.001). In univariate and multivariate regression analysis, plasma leptin levels were significantly correlated with TBARS (p <0.01 and p <0.01) in obese subjects. Plasma TBARS were also inversely correlated with NOx in hypertensive obese subjects (r = -0.412, p <0.01).
Our results have shown that elevated leptin levels may be associated with increased oxidative stress and free-radical-induced decreased NOx levels. Therefore, hyperleptinemia may be an important contributor to the generation of hypertension in obesity.
最近有证据表明，瘦素在体内可诱导人内皮细胞产生氧化应激，而在原发性高血压患者中氧化应激增加，这可能进一步促进动脉粥样硬化及其他心血管疾病的发展。我们在肥胖高血压动脉粥样硬化模型中研究了血浆瘦素水平与血浆脂质过氧化及一氧化氮代谢产物（NOx）之间的关联。
测定年龄匹配的非肥胖正常血压女性受试者（n = 30）、肥胖正常血压女性受试者（n = 45）和肥胖高血压女性受试者（n = 50）的血浆瘦素、脂质过氧化和NOx水平。采用免疫放射分析法测定血浆瘦素水平。用分光光度法将脂质过氧化测定为硫代巴比妥酸反应性物质（TBARS）。采用酶法测定NOx水平。
我们发现肥胖患者血浆瘦素和TBARS水平升高，肥胖高血压患者的血浆瘦素和TBARS水平显著高于肥胖正常血压患者（p <0.001和p <0.001）。肥胖高血压患者的血浆NOx水平显著低于肥胖正常血压患者（p <0.001）。在单因素和多因素回归分析中，肥胖受试者的血浆瘦素水平与TBARS显著相关（p <0.01和p <0.01）。在高血压肥胖受试者中，血浆TBARS也与NOx呈负相关（r = -0.412，p <0.01）。
我们的结果表明，瘦素水平升高可能与氧化应激增加及自由基诱导的NOx水平降低有关。因此，高瘦素血症可能是肥胖中高血压发生的重要促成因素。
