Oxidative and nitrosative stress in association with DNA damage in coronary heart disease.

INTRODUCTION: Oxidative and nitrosative stress caused by a disturbance in the homeostasis of pro-oxidants and antioxidants play a vital role in the pathogenesis of coronary heart disease (CHD). Enhanced formation of reactive oxygen species/reactive nitrogen species may also affect the oxidation/nitration of biomolecules such as lipids, proteins and DNA. The present study was undertaken to estimate oxidative and nitrosative stress, and to evaluate oxidative DNA damage. METHODS: The study population consisted of 120 patients with angiographically documented CHD and an equal number of age- and gender-matched healthy controls. Lipid profiles were estimated using Glaxo kits. Estimation of plasma malondialdehyde (MDA), nitrite/nitrate and comet assay were carried out using previously published methods. RESULTS: Lipid profiles were significantly different in patients with coronary artery disease compared to the controls (p-value less than 0.01). The levels of MDA, nitrite/nitrate and DNA damage in the patients were significantly higher compared to the controls, and a strong correlation was found between the comet tail length and the MDA and nitrite/nitrate levels. Further analysis revealed that the influence of nitrite/nitrate was greater than that of MDA. CONCLUSION: Our results indicate that abnormal levels of lipid profiles, along with increased oxidative and nitrosative stress as well as somatic DNA damage, could be important pathogenic factors that act as additional prognostic predictors. They may also serve as potential targets for therapeutic strategies in CHD for early management and prevention of the disease.

Serum cholinesterases in Down syndrome children before and after nutritional supplementation.

INTRODUCTION: Down syndrome (DS) children have different degrees of developmental abnormalities associated with mental retardation. A cascade of pathological changes triggering alterations in cholinesterase-mediated functions seems to be the cause of neuronal and muscular dysfunctions, such as memory loss, disturbed cognitive skills, and language impairment in virtually all DS individuals, but there are currently no efficacious biomedical treatments for these central nervous system-associated impairments. The present study aimed to evaluate the effects of nutritional supplementation on cholinesterases in serum of DS children. METHODS: Activities of acetyl- and butyrylcholinesterase were analysed in the serum samples of 40 DS children, along with an equal number of age- and sex-matched controls under study. RESULTS: The activities of serum acetyl- and butyrylcholinesterase were found to be low in DS children before nutritional supplementation, compared to controls, and showed considerable improvement after six months of supplementation of zinc in combination with antioxidant vitamins and minerals. A significant improvement was also observed in cognitive skills and behavioural patterns after nutritional supplementation. CONCLUSION: The present pilot study suggests the significance of early intervention with nutritional supplementation in DS children to ameliorate the severity of this disorder.

Oxidative stress and total antioxidant status in myocardial infarction.

INTRODUCTION: Coronary artery disease is caused by the additive and interactive effects of inherited and environmental factors. Substantial evidence shows that reactive oxygen species (ROS) play a vital role in the aetiopathogenesis of atherosclerosis. Our study has been designed to evaluate the oxidative stress due to ROS and assess the antioxidant protection against ROS, in addition to the major risk factors, like lipid profiles, habit of smoking and conditions such as diabetes mellitus and hypertension, in myocardial infarction (MI) patients. METHODS: World Health Organisation criteria were followed in the selection of the subjects. 150 patients with MI were included in the study along with equal number of age- and gender-matched controls. Malondialdehyde (MDA) and nitrite/nitrate levels were measured as markers of oxidative stress of free radical induced injury, and total antioxidant status was determined to assess the antioxidant protection against ROS, along with the lipid profiles. RESULTS: The levels of total cholesterol, low density lipoprotein cholesterol, triglycerides, MDA and nitrite/nitrate were found to be significantly high, while high density lipoprotein cholesterol and total antioxidant capacity were significantly low in MI patients compared to controls. CONCLUSION: Our study revealed the importance of determining the total antioxidant status in MI, in addition to the markers of oxidative stress and lipid profiles to enable the formulation of specific antioxidant therapies for an early intervention and better management of the disease. The study also suggests initiating lifestyle modifications as a preventive measure to reduce the burden of the disease.