Controversial association between serum levels of vitamin D and IgE response in obesity: A cross sectional studies in Children of the Colombian Caribbean

Abstract

Event Abstract Back to Event Controversial association between serum levels of vitamin D and IgE response in obesity: A cross sectional studies in Children of the Colombian Caribbean Eduardo A. Egea Bermejo1*, Luis C. Fang Mercado2, 3, Nicole S. Pereira Sanandres1, Kenny Y. Del Toro Camargo4, Jorge Ordoñez4, Maria D. Garavito Galofre5, Carlos Silvera Redondo5 and Gloria Garavito De Egea1 1 Universidad del Norte, Medicina, Colombia 2 Universidad de Cartagena, Facultad de Odontologia, Colombia 3 Universidad Rafael Nuñez, Odontologia, Colombia 4 Universidad del Norte, Medicina, Colombia 5 Universidad del Norte, Medicina, Colombia Background: Previous studies have evaluated the association between vitamin D and allergic response in atopic individuals. Example of this is that vitamin D deficiency behave as a risk factor for increased IgE response. In obese patients is still uncertain this association. Meanwhile, the gene variants in the vitamin D receptor (VDR) have been associated with multiple complex diseases, in the case of obesity can alter the expression of vitamin D receptor in adipose tissue and in turn modify the behavior of obesity. Currently there are few studies reporting this association in the Colombian Caribbean populations. Objective: Analyze the genetic association of the VDR SNPs: TaqI, ApaI, BsmI and FokI with obesity susceptibility and its influence with serum vitamin D levels and total IgE response in children. Methods: An analytical crosssectional study (cases = 120 and controls n = 182) with obese children between 5 and 17 years old from the Colombian Caribbean coast was made. The SNPs were genotyped by RT-PCR and Taqman probes. Serum levels of 25-hydroxy vitamin D were measured by ELISA; concentrations <10 ng / mL (vitamin D deficient), 10-30ng / mL (insufficient), ≥30 to <100 ng / mL (Enough) and ≥100ng / mL (High). Total IgE was classified according to age and sex of the participants, Total IgE> 100 IU / mL on average it was considered high. P values <0.05 were statistically significant. Results: Our results showed an association between high levels of vitamin D and childhood obesity, 48.3% (n = 58) of cases had levels> 100 ng / mL compared to 0.5% (n = 1) in controls. In the control group, the average of vitamin D level was 36.4 ± 22.9 ng / mL unlike obese was 93.6 ± 27.8 ng / mL (p = 0.00). As regard to the total IgE response, no difference was observed between the study groups. However, both obese and controls had elevated levels (317.07 ± 331.5 vs 280.6 ± 272.7; p = 0.786). The analysis of genetic polymorphism association between VDR and obesity showed no difference significant statistically in allelic and genotypic distribution of SNPs; all genetic polymorphisms were in Hardy-Weingber equilibrium Our results showed no association between genetic variants with Total serum vitamin D and IgE in children with obesity. When correlating serum levels of vitamin D and total IgE not an association was observed (Spearman Rho: 0.023; p = 0.641). Conclusions: The results obtained in this study show no vitamin D deficiency associated with obesity in this population group. However, independent of the systemic condition of the individual, high total IgE response in most of the population is observed. We have previously reported the absence of vitamin D and high total IgE response in different age groups in the Colombian Caribbean coast. The observed association with childhood obesity in the studied population is specifically given by the serum vitamin D and not the IgE response. Furthermore these serum biomarkers are not associated with each other, at least directly. Validation of these findings with further studies in populations with a genetic load and similar socioeconomic characteristics is required. Acknowledgements We gratefully acknowledge to The Universidad del Norte and Colciencia for their financial support and the patients for their collaboration.