Hipovitaminose D em pacientes com fibrose cística: prevalência e influência do polimorfismo BsmI (rs 1544410) do gene VDR na suplementação com vitamina D sobre marcadores de processo inflamatório e estresse oxidativo

• Autor(a) principal: Queiroz, Dayanna Joyce Marques
• Data de Publicação: 2021
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/22362
• topic: Hipovitaminose D; Polimorfismo genético; Fibrose cística; Inflamação; Hypovitaminosis D; Genetic polymorphism; Cystic fibrosis; Inflammation; CNPQ::CIENCIAS DA SAUDE::NUTRICAO

Patients with Cystic Fibrosis are at risk for vitamin deficiency due to pancreatic insufficiency. Vitamin deficiency is possibly associated with an inflammatory state and oxidative stress. The presence of genetic polymorphisms in the VDR appears to play a role in supplementation response and clinical effects. The aim of the present study was to evaluate the prevalence of hypovitaminosis D and the influence of the VDR gene’s BsmI polymorphism (rs 1544410) on vitamin D megadose supplementation on inflammatory process and oxidative stress markers in patients with Cystic Fibrosis. A multicenter cross-sectional study was performed, followed by a single-arm nonrandomized pre and post-study with patients who had 25(OH)D insufficiency or deficiency. Patients with Cystic Fibrosis were > 5 years old, both genders. In the first stage of the study, 48 patients with Cystic Fibrosis participated, who were interviewed regarding sociodemographic profile, skin type photo and sun exposure, anthropometric data (weight, height, Body Mass Index), food consumption, biochemical evaluation for analysis of renal function and liver, calcium, parathyroid hormone (PTH), inflammatory process (C-reactive protein (CRP) and alpha-1-acid glycoprotein- A1GPA) and oxidative stress (malondialdehyde- MDA and total antioxidant capacity- CAOT) and genotypic determination of the BsmI polymorphism (rs 1544410). Patients diagnosed with insufficiency and/or vitamin D deficiency, were supplemented with vitamin D, 4000 IU/day for children aged 5 to 10 years and 10,000 IU/day for children over 10 years, adolescents and adults, for 8 weeks. Statistical analysis was performed using the “Statistical Pacage for the Social Sciences” and Prism 6, adopting a significance level of p<0.05. It was observed that the majority of the population had Vitamin D insufficiency and/or deficiency (64.6%). There was no association between vitamin D levels and gender, sun exposure, photo skin type, nutritional status and genotypic variation of the BsmI polymorphism. After multivariate linear regression analysis, the MDA showed an inverse association with the blood values of 25- Hydroxyvitamin D (p= 0.01), but conditioned by markers of the inflammatory process. When only oxidative stress is evaluated, this association disappears. Individuals with the BB and Bb genotypes showed increased serum levels of 25(OH)D, but not those with the bb genotype of the BsmI polymorphism of the VDR gene. The analysis paired with the BB genotype showed a reduction in A1GPA. The bb genotype showed high levels of MDA compared to the pre intervention period. In conclusion, there was a high prevalence of hypovitaminosis D in patients with Cystic Fibrosis, presenting an inverse relationship with oxidative stress when associated with markers of the inflammatory process. As for the BsmI polymorphism of the VDR gene, genotype variation seems to influence vitamin D levels and markers of inflammatory process and oxidative stress. The presence of polymorphism appears to influence the effect of supplementation and clinical response in patients with Cystic Fibrosis. We suggest that our studies take longer and more patients to understand ideal levels for vitamin D correction and the relationship with genetic polymorphisms in the VDR gene.