Obesity, dyslipidemia and vitamin D deficiency are growing health problems in the Arabian Gulf region. Their association with each other is yet to be clarified.
Three-hundred and fourteen Bahraini ...adults, 164 males and 150 females comparable in median age (34.5 vs. 31.0 yrs), body mass index (BMI), and ethnicity were recruited. The plasma level of 25-hydroxyvitamin D3 (25OHD3) was measured by chemiluminescent immunoassay and lipid profile parameters were measured by an automated clinical chemistry analyzer. Based on BMI, study subjects were grouped into underweight, normal, overweight, moderate obesity, and severe obesity subjects.
The results revealed an extremely high prevalence of vitamin D deficiency (79.9%) and insufficiency (18.8%). The predictors of low 25OHD3 levels were female gender, small age, conservative dressing, least exposure to sunlight, and less fish intake. In all subjects, the lowest 25OHD3 level was seen in underweight and severe obesity groups. Furthermore, the 25OHD3 level was significantly higher in males as compared to females and it was positively correlated with the age. However, detailed analysis showed that overweight males unlike females had the highest 25OHD3 levels which were significantly higher than in the severely obese males. While the lipid profile parameters were positively correlated with BMI, the total and LDL cholesterols were negatively correlated with the levels of 25OHD3 in males.
Vitamin D deficiency was associated with both severely obese and underweight subjects, in the former it was likely to be institutional while in the latter it was likely to be nutritional. Furthermore, hypercholesterolemia (LDL-C) was associated with 25OHD3 sub-normality. Further analysis revealed that the significant associations were gender-dependent.
We investigated a possible association between polymorphisms in vitamin D binding protein (GC) and vitamin D receptor (VDR) genes and obesity in Bahraini adults. For this purpose, 406 subjects with ...varying body mass indexes (BMIs) were selected. Plasma levels of 25-hydroxyvitamin D3 (25OHD3) were measured by chemiluminescence immunoassay. Six single nucleotide polymorphisms, 2 in the VDR gene (rs731236 TC and rs12721377 AG) and 4 in the GC gene (rs2282679 AC, rs4588 CA, rs7041 GT, and rs2298849 TC), were genotyped by real-time polymerase chain reaction. We found that the rs7041 minor allele (G) and rare genotype (GG) were associated with higher BMI (p = 0.007 and p = 0.012, respectively), but they did not influence 25OHD3 levels. However, the minor alleles of rs2282679 (A) and rs4588 (C) were associated with low 25OHD3 plasma levels (p = 0.039 and p = 0.021, respectively), but not with BMI. Having categorized the subjects based on their sex, we found that (i) rs7041 GG associated with high BMI in females (p = 0.003), (ii) rs4588 CC associated with high BMI in females (p = 0.034) and low 25OHD3 levels in males (p = 0.009), and (iii) rs12721377 AA associated with low 25OHD3 levels in females (p = 0.039). Notably, none of the common haplotypes (6 in the GC gene and 3 in the VDR gene) were associated with BMI. Therefore, polymorphisms in the GC (rs2282679, rs4588, rs7041) and VDR (rs12721377) genes were independently associated with obesity and 25OHD3 levels with a clear sex dimorphism.
We investigated a possible association between polymorphisms in vitamin D binding protein (GC) and vitamin D receptor (VDR) genes and obesity in Bahraini adults. For this purpose, 406 subjects with ...varying body mass indexes (BMIs) were selected. Plasma levels of 25-hydroxyvitamin D3 (25OHD3) were measured by chemiluminescence immunoassay. Six single nucleotide polymorphisms, 2 in the VDR gene (rs731236 TC and rs12721377 AG) and 4 in the GC gene (rs2282679 AC, rs4588 CA, rs7041 GT, and rs2298849 TC), were genotyped by real-time polymerase chain reaction. We found that the rs7041 minor allele (G) and rare genotype (GG) were associated with higher BMI (p = 0.007 and p = 0.012, respectively), but they did not influence 25OHD3 levels. However, the minor alleles of rs2282679 (A) and rs4588 (C) were associated with low 25OHD3 plasma levels (p = 0.039 and p = 0.021, respectively), but not with BMI. Having categorized the subjects based on their sex, we found that (i) rs7041 GG associated with high BMI in females (p = 0.003), (ii) rs4588 CC associated with high BMI in females (p = 0.034) and low 25OHD3 levels in males (p = 0.009), and (iii) rs12721377 AA associated with low 25OHD3 levels in females (p = 0.039). Notably, none of the common haplotypes (6 in the GC gene and 3 in the VDR gene) were associated with BMI. Therefore, polymorphisms in the GC (rs2282679, rs4588, rs7041) and VDR (rs12721377) genes were independently associated with obesity and 25OHD3 levels with a clear sex dimorphism. Key words: obesity, vitamin D receptor, vitamin D binding protein, polymorphism, Bahrain. Nous examinons une association possible entre les polymorphismes de la proteine porteuse de vitamine D (<< GC >>) et les genes des recepteurs de la vitamine D (<< VDR >>) et l'obesite chez des adultes bahreinis. A cette fin, nous examinons 406 sujets a l'indice de masse corporelle (IMC) different. On mesure le taux plasmatique de 25-hydroxyvitamine D3 (<< 25OHD3 >>) au moyen par la technique d'immunoessai par chimioluminescence. Le genotypage au moyen de la reaction en chaine par polymerase en temps reel revele six polymorphismes des nucleotides simples : deux dans le gene VDR (rs731236 TC et rs12721377 AG) et quatre dans le gene GC (rs2282679 AC, rs4588 CA, rs7041 GT et rs2298849 TC). D'apres nos observations, l'allele mineur rs7041 (G) et un genotype rare (GG) sont associes a un IMC plus eleve (p = 0,007 et p = 0,012, respectivement), mais n'influencent pas le taux de 25OHD3. Toutefois, les alleles mineurs de rs2282679 (A) et rs4588 (C) sont associes a un faible taux plasmatique de 25OHD3 (p = 0,039 et p = 0,021, respectivement), mais pas a l'IMC. Apres la repartition des sujets selon le sexe, on observe ce qui suit : (i) rs7041 GG est associe a un IMC eleve chez les femmes (p = 0,003), (ii) rs4588 CC est associe a un IMC eleve chez les femmes (p = 0,034) et a un faible taux de 25OHD3 chez les hommes (p = 0,009) et (iii) rs12721377 AA est associe a un faible taux de 25OHD3 chez les femmes (p = 0,039). Fait a noter, aucun des haplotypes reguliers (6 dans le gene GC et 3 dans le gene VDR) n'est associe a l'IMC. En conclusion, les polymorphismes des genes GC (rs2282679, rs4588, rs7041) et VDR (rs12721377) sont associes independamment a l'obesite et au taux de 25OHD3 incluant un dimorphisme sexuel net. Traduit par la Redaction Mots-cles: obesite, recepteur de vitamine D, proteine porteuse de vitamine D, polymorphisme, Bahrein.
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