Overview of genomics and post-genomics research on type 2 diabetes mellitus: Future perspectives and a framework for further studies

In this review, we briefly outlined salient features of pathophysiology and results of the genetic association studies hithertoconducted on type 2 diabetes. Primarily focusing on the current status of genomic research, we briefly discussed the limitedprogress made during the post-genomic era and tried to identify the limitations of the post-genomic research strategies. Wesuggested reanalysis of the existing genomic data through advanced statistical and computational methods and recommended integrated genomics-metabolomics approaches for future studies to facilitate understanding of the gene-environment interactions in the manifestation of the disease. We also propose a framework for research that may be apt fordetermining the effects of urbanization and changing lifestyles in the manifestation of complex genetic disorders like type 2diabetes in the Indian populations and offset the confounding effects of both genetic and environmental factors in thenatural way

Histopathological changes due to the effect of selenium in experimental cockerels.

Background & objectives: Selenium usually acts as an antioxidant at optimal levels in the body and increased levels are toxic. In this study an attempt was made to evaluate the effect of an optimum dose (0.14 mg) of selenium on histopathological changes in experimental hypercholesterolemia in cockerels. Methods: the effect of selenium (0.14 mg) was investigated on histopathological changes in four tissues namely liver, kidney, heart, and descending aorta in cockerel animal model. Animals were either fed with stock diet (group C), stock diet with cholesterol (group CH), stock diet with selenium (group Se), stock diet, selenium and cholesterol (group CH+Se) for six months. Animals were sacrified and the tissues were isolated and subjected to histopathological study. Results: xanthochromatic collections in liver were observed in group CH; hydropic degeneration in group Se and lobular disarray, hydropic degeneration and kuppfer cell hyperplasia in group CH+Se were observed. In kidney, mild mononuclear infiltration was observed in interstitium in groups CH, Se and CH+Se. myocyte disruption, and mononuclear infiltration in group CH and cCH+Se, and disruption of muscle bundles with vascular congestion in group Se were observed. Smooth muscle proliferation in the media of blood vessel was observed in groups CH, Se and CH+Se. Interpretation & conclusions: Tthe results of the present study suggested that the optimum dose of (140 μg/day) feeding induced atherogenesis by inflammation and smooth muscle proliferation in cockerels with experimentally induced hypercholesterolaemia.

Prevalence of coronary artery disease and coronary risk factors in an urban population of Tirupati.

AIMS AND OBJECTIVES: To determine the prevalence of coronary heart disease and its risk factors in the urban population of Tirupati. METHODS: The urban population of Tirupati is spread into 20 wards. Thirteen wards were selected randomly and systematic random sampling was done to identify the sampling unit household. A total of 1519 subjects (539 males and 980 females) 20 years of age formed the sample of the study. Demographic (age, sex, occupation, education and income), behavioral (smoking), anthropometric (height, weight, waist and hip circumferences) and physiological (blood pressure) parameters were noted and recorded and biochemical parameters (serum glucose, total cholesterol, triglycerides, HDL cholesterol levels) were assayed. Coronary artery disease was diagnosed based on history and ECG changes suggestive of ST-segment depression (Minnesota 4-1 to 4-2) or Q wave changes (Minnesota codes 1-1-1 to 1-1-7) or T wave changes (Minnesota codes 5-1 to 5-3). RESULTS: The overall prevalence in the study population was 12.63 (192 cases). In males it was 6.86 (37 cases) and in females 15.81 (155 cases). The major risk factors in this population were central obesity 1003 (66%) [male 320 (59.4%) and females 683 (41.12%)], low HDL cholesterol 709 (46.67%) [male 284 (52.69%) and females 425 (43.36%)], obesity 588 (38.07%) [males 187 (34.32%) and females 403 (41.12%)], high triglyceride levels (>or= 150 mg/dl) 444 (29.22%)[(males 173 (32.09%) and females 272 (27.75%)], high cholesterol levels (>or= 200mg/dl) [(males 127 (23.56%) and females 278 (28.36%)] and hypertension 396 (26.06) [(males 149 (27.64%) and females 247 (25.20%)]. Around a fraction of subjects had metabolic syndrome 371 (24.42%) [(males 90 (16.69%) and females 281 (28.64%)]. In multivariate regression analysis, age (OR 1.05 95% CI 1.01-1.09 p<0.01) and high serum LDL cholesterol level (OR 4.62 95% CI 2.29-9.32 p<0.001) in males and serum triglycerides (OR 1.003 95% CI 1.000-1.005) in females were associated with CAD. CONCLUSIONS: Association of age, high LDL cholesterol in males and triglycerides in females with CAD shows the importance of these risk factors in this population. This was only a cross-sectional study done at one point of time. Clinical importance of these risk factors needs to be tested in the longitudinal study.

Association of serum antioxidants and risk of coronary heart disease in South Indian population.

BACKGROUND AND AIM: Higher prevalence of coronary heart disease (CHD) has been reported in south Indian population, which cannot be accounted for by the traditional risk factors like hyperlipidemia. Identification of new risk factors may help in treatment and prevention of CHD in this part of the world. In an attempt to investigate the causes of increased incidence of CHD in this part of the world, we intended to look for oxidative stress in our patients as a possible risk factor. As an initial step in this perspective, a case- control study was conducted to find out the serum antioxidant levels and their association with CHD in south Indian population. SETTINGS AND DESIGN: A tertiary care hospital; Case--control study. MATERIALS AND METHODS: One hundred thirty nine angiographically proven CHD patients (aged 29-75 years) were studied against 59 population based healthy controls (aged 29-72 years) free of CHD. Fasting serum cholesterol, triglycerides, HDL cholesterol, erythrocyte and plasma glutathione peroxidase and superoxide dismutase were estimated on automated clinical chemistry analyzer. LDL cholesterol and VLDL cholesterol were calculated. Vitamins A and E were estimated using high performance liquid chromatography (HPLC). STATISTICAL ANALYSIS: Unpaired t test was used to compare means. Binary logistic regression was done to find out the association between dependent and independent variables. RESULTS: Significantly higher levels of Total Cholesterol/HDL cholesterol and LDL cholesterol/HDL cholesterol ratio and lower HDL cholesterol levels were observed in patients when compared to controls. No significant difference of plasma and erythrocyte glutathione peroxidase and superoxide dismutase activity was observed between patients and controls. Significantly lower levels of vitamin E in patients than in controls was observed (P<0.001). Serum vitamin E was inversely associated with coronary heart disease even after controlling for age and other coronary risk factors (Odds ratio 0.898, 95% CI 0.826-0.976 P=0.01). CONCLUSIONS: The results of present study suggest that deficiency of vitamin E may be an independent risk factor of CHD. This study brings out the need for long- term monitoring of vitamin E supplementation as a preventive measure for CHD in the population studied.

Seroprevalence of IgG antibodies to Chlamydia pneumoniae and Helicobacter pylori among coronary heart disease patients and normal individuals in South Indian population.

In recent years, the role of infectious agents in the aetiology of atherosclerotic disease has come to the forefront. In the present study, seroprevalence (IgG) of chlamydia pneumoniae and helicobacter pylori in patients with atherosclerotic coronary heart disease was compared to normal healthy adults. Out of a total of 117 patients 101 had unstable angina (UA) and 16 had chronic stable angina (CSA). C. pneumoniae seropositivity was found in 66% of patients with UA and 94% of CSA patients. The corresponding figures for H. pylori were 58% and 56% respectively. In comparison, 81% of healthy adults were seropositive for C. pneumoniae and 53% for H.pylori. No significant association was found between CHD and the infectious agents. However, this study has revealed a high infection by C. pneumoniae as well as H.pylori in this part of India.