Rohrbach Susanne, Martin Antonio, Niemann Bernd, Cherubini Antonio
Institute of Pathophysiology, Martin-Luther-University Halle-Wittenberg, Germany.
Eur J Heart Fail. 2008 Mar;10(3):226-32. doi: 10.1016/j.ejheart.2008.01.001. Epub 2008 Feb 20.
Indirect observations are compatible with cardiac vitamin C deficiency as one contributory factor to oxidative stress in heart failure, but data on ventricular vitamin C content are lacking. Here, we used the well established model of aortic-banded rats at the stage of compensated hypertrophy (6 weeks after banding) and at the transition to cardiac failure (22 weeks after banding) to analyze vitamin C, vitamin E, protein carbonyls and malondialdehyde tissue content together with the respective plasma concentrations. Furthermore, we investigated the expression of the vitamin C transporters SVCT1 and SVCT2 in the left ventricle (LV). Aortic-banded rats, independently from their age, had higher malondialdehyde and protein carbonyl levels in plasma and LV tissue compared to sham-operated animals indicating increased oxidative stress. Plasma vitamin C remained unaffected from cardiac overload, while LV vitamin C was elevated in both stages of hypertrophy together with an increased expression of the vitamin C transporter SVCT2 suggesting increased vitamin C uptake. The levels of antioxidants and lipid peroxides were similar 6 and 22 weeks after aortic banding. Therefore, the accumulation of vitamin C in compensated hypertrophy and in decompensated failure excludes cardiac vitamin C deficiency as a primary factor to oxidative stress in this model.
间接观察结果表明,心脏维生素C缺乏可能是导致心力衰竭氧化应激的一个因素,但目前尚缺乏关于心室维生素C含量的数据。在此,我们利用已建立的主动脉缩窄大鼠模型,在代偿性肥大阶段(缩窄后6周)和向心力衰竭转变阶段(缩窄后22周),分析维生素C、维生素E、蛋白质羰基和丙二醛的组织含量以及各自的血浆浓度。此外,我们还研究了维生素C转运体SVCT1和SVCT2在左心室(LV)中的表达。与假手术动物相比,主动脉缩窄大鼠无论年龄大小,其血浆和左心室组织中的丙二醛和蛋白质羰基水平均较高,表明氧化应激增加。心脏超负荷对血浆维生素C没有影响,而在肥大的两个阶段左心室维生素C均升高,同时维生素C转运体SVCT2的表达增加,提示维生素C摄取增加。主动脉缩窄6周和22周后,抗氧化剂和脂质过氧化物水平相似。因此,在代偿性肥大和失代偿性心力衰竭中维生素C的积累排除了心脏维生素C缺乏作为该模型氧化应激主要因素的可能性。