Prevalence of specific cardiovascular disease risk factors in young Newfoundland and Labrador adults living in urban and rural communities.

INTRODUCTION: The province of Newfoundland and Labrador has a high rate of cardiovascular disease. Risk factors of cardiovascular disease have not been well studied in young adults. There are reasons to believe that the prevalence of cardiovascular disease risk factors may be higher in young adults residing in rural versus urban settings. METHODS: 540 men and women, ages 18 to 34 years and residing in urban and rural areas of Newfoundland and Labrador were compared for cigarette smoking and for body size. Both body mass index and waist circumference measures were used to indicate body size. Education level and family income were also studied. Data were collected via personal interview as part of a larger study, Nutrition Newfoundland and Labrador. RESULTS: No difference was noted between the 2 groups in regular smoking or BMI. More female rural residents had a waist circumference above the accepted cut-off compared with female urban residents (32.5% v. 17.0%). CONCLUSION: Young adults in urban and rural areas both experience high rates of modifiable risk factors for CVD. Some may be more prevalent in rural areas. Prevention programs should include young adults, especially those residing in rural areas.

Molecular effects of homocysteine on cbEGF domain structure: insights into the pathogenesis of homocystinuria.

Homocystinuria is an inborn error of methionine metabolism that results in raised serum levels of the highly reactive thiol-containing amino acid homocysteine. Homocystinurics often exhibit phenotypic abnormalities that are similar to those found in Marfan syndrome (MFS), a heritable connective tissue disorder that is caused by reduced levels of, or defects in, the cysteine-rich extracellular matrix (ECM) protein fibrillin-1. The phenotypic similarities between homocystinuria and MFS suggest that elevated homocysteine levels may result in an altered function of fibrillin-1. We have used recombinant calcium binding epidermal growth factor-like (cbEGF) domain fragments from fibrillin-1, and an unrelated protein Notch1, to analyse the effects of homocysteine on the native disulphide (cystine) bonds of these domains. We show using analytical reverse phase, high performance liquid chromatography (HPLC), electrospray ionisation mass spectrometry (ESI-MS) and limited proteolysis that homocysteine attacks intramolecular disulphide bonds causing reduction of cystine and domain misfolding, and that the effects of homocysteine are dependent on its concentration. We also identify the importance of calcium binding to cbEGF domains for their stabilisation and protection against homocysteine attack. Collectively, these data suggest that reduction of intramolecular cbEGF domain disulphide bonds by homocysteine and the resulting disruption of this domain fold may contribute to the change in connective tissue function seen in homocystinuria. Furthermore, since we show that the effects of homocysteine are not unique to fibrillin-1, other cbEGF-containing proteins may be implicated in the pathogenic mechanisms underlying homocystinuria.