Search

Background: There is evidence demonstrating that the contribution of sedentary behavior and effect of physical activity on metabolic phenotypes is mediated by polymorphisms in genes. Methods: The type and frequency of physical activity was assessed by means of structured questionnaires in 1555 South African school learners. Anthropometric measurements, blood pressure, fasting blood glucose and lipids were measured using standard procedures. The effect of different types and frequency of physical activity on obesity-related traits was assessed in relation to MC3R T6K and V811 genotypes in 430 of the learners. Results: Levels of total cholesterol were significantly lower in learners carrying the MC3R T6K and V81I minor alleles, after adjusting for age, race, gender, and each specific physical activity category. An activity-by-genotype interaction was also detected: learners heterozygous for the V81I polymorphism and performed house chores often had reduced total cholesterol. Though no association was observed between frequency of physical activity and BMI, television viewing was significantly associated with an increase in height, weight and marginally with waist circumference. Conclusion: Our findings suggest that physical activity even in the form of house chores has a positive effect on metabolic traits and this effect is further enhanced in the presence of MC3R polymorphisms. [ABSTRACT FROM AUTHOR]

Objective: Metabolic syndrome (MetS) and its associated cardiovascular risk are on the increase in children. High-sensitivity C-reactive protein (hs-CRP) has emerged as a useful marker for inflammation associated with atherosclerosis and cardiovascular disease. Our aim was to determine the distribution of hs-CRP in an effort to identify the MetS variable that is critical in modulating plasma CRP levels in a population of South African adolescents. Design: A cross-sectional analytical study design was used for this investigation, where the dependent and independent variables were measured simultaneously. Methods: Anthropometric variables, blood pressure, fasting blood glucose and lipids were performed on 324 consenting learners aged 15-18 years from three different ethnic groups (Black, White and Coloured). The National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) for ages 15-18 year olds was used to define MetS. Results: The prevalence of MetS and obesity was 3.7% and 7.1%, respectively. The hs-CRP levels were significantly higher in subjects with a waist-circumference greater than the 90th percentile (p < 0.01) and in obese learners with MetS, but was lower in adolescents with normal weight and MetS. Median hs-CRP levels increased with an increasing number of metabolic abnormalities and exceeded 3 mg/L in 19% of adolescents. Gender and ethnic differences were observed. Conclusion: Our findings suggest that obesity and waist circumference appear to be major mediators of hs-CRP levels in South African adolescents. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate the levels of non-esterified fatty acids in plasma from patients with multiple sclerosis and further to correlate these findings with the neurological profile as measured by the Kurtzke Expanded Disability Status Scale. Methods: Plasma non-esterified fatty acids and esterified fatty acids from 30 control subjects and 31 patients with multiple sclerosis were measured by gas chromatography. Results: Non-esterified fatty acids C18:2n-6, C20:4n-6, C16:1n-7, C18:1n-7, C18:1n-9, C14:0, C16:0 and C18:0 were significantly increased in plasma from patients with multiple sclerosis, P ≤ 0.01, while esterified fatty acid C18:2n-6 was decreased, P = 0.003. Fatty acid PC C16:1n-7 and non-esterified fatty acids C16:1n-7, C18:1n-7 and C18:1n-9 showed positive and fatty acids C18:1n-9, C20:0, C22:0 and C24:0 showed inverse correlations with the Functional System Scores. Conclusions: We have identified increased monounsaturated non-esterified fatty acids in plasma from patients with multiple sclerosis as indicative of a worse disease outcome. Further, the decrease in fatty acid C18:2n-6, with increases in non-esterified fatty acids C18:2n-6 and C20:4n-6, suggested a role for these eicosanoid precursor fatty acids in the inflammatory condition experienced by these patients. [ABSTRACT FROM AUTHOR]