Study of Oxidative Stress in Essential Hypertension
B.K. Agarwal1, Tripti Saxena2, Sabiha Naz21Department of Medical Biochemistry,Index Medical College,Indore (M.P.) 2Department of Medical Biochemistry,Gandhi Medical College,Bhopal (M.P.)
Abstract: Essential hypertension is associated with an elevation of reactive oxygen species (ROS) which reacts with membrane lipids to form lipid hydroperoxides that decomposes to form Malondialdehyde (MDA) an indicator of oxidative stress. Endogenous antioxidant enzyme, Superoxide dismutase (SOD) counteracts oxidative stress. This study aims at understanding the role of oxidative stress in essential hypertension. The study comprised of 50 confirmed cases of hypertension and 50 age and sex matched controls .Inclusion criteria includes patients with blood pressure ≥ 140/90 mm of Hg, while patients with secondary hypertension, stroke, CAD,MI and diabetes mellitus are excluded. Serum SOD estimated spectrophotometrically by Mishra H.P. and Fridovich I,1972 method and Plasma MDA by colorimetric method of Satoch K.et al. SOD activity was statistically significantly (p<0.0001) decreased while MDA level was statistically significantly (p<0.0001) increased in hypertensives compared to controls. Patients suffering from hypertension have increased ROS activity which oxidizes nitric oxide (NO) and affect vascular tone.Lassegue et al (2004) also found convincing evidence that ROS is an intrinsic part of pathology of hypertension. If oxidative stress is indeed a cause or consequence of hypertension, then reduction in oxidative damage may result in a reduction in blood pressure. Antioxidants like Vit.A,Vit.C and Vit E which are present in vegetables, citrus fruits and oils respectively are able to trap ROS and thus may be capable of reducing oxidative damage and possibly blood pressure. Estimation of oxidative stress markers (SOD and MDA) is simple and inexpensive; it can be used to predict the development of atherosclerotic disease like coronary artery disease, cerebrovascular disease and renal complications associated with essential hypertension. Oxidative stress markers estimation may also be helpful in assessing the usefulness of antihypertensive drugs in prevention of associated complications.
Keywords: Superoxide dismutase; Malondialdehyde; Reactive Oxygen Species Back to TOC