Terapia antiobesidade com cálcio papel da ação da vitamina D no adipócito

• Autor(a) principal: Nobre, Jessica Lopes
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/12663
• topic: Early weaning; Programming; Obesity; Calcium diet; Vitamin D; Desmame precoce; Programação; Obesidade; Cálcio; Vitamina D; Obesidade; Adipócitos; Cálcio Efeito fisiológico; Desmame; Vitamina D; CNPQ::CIENCIAS BIOLOGICAS::FISIOLOGIA::FISIOLOGIA DE ORGAOS E SISTEMAS::FISIOLOGIA ENDOCRINA

Obesity is a worldwide epidemic and in Brazil more than 50% of people are overweight/obese. We show that a rich calcium diet has an anti-obesity effect in obese animals programmed by early weaning (EW), an effect mediated by vitamin D action, which appears to directly regulate adipogenesis. Thus, we decided to evaluate the effect of vitamin D on the metabolism of adipose tissue in vivo with EW animals and in vitro with 3T3L1 lineage. At birth, lactating rats were divided into: EW Group, dams were wrapped with a bandage to interrupt lactation in the last 3 days of lactation; C Group, dams whose pups had free access to breast milk during the lactation period (21 days). At 120 days-old, EW offspring were subdivided into: EW standard diet; EW, received calcium supplementation (EWCa, calcium carbonate 10g / kg chow). We also use 3T3L1 cell line to incubated with calcitriol (1,25 (OH) 2D) or leptin. Significance level was at p<0,05. Ew offspring had lower body weight during the 3 days of weaning and lower ionized calcium, without changing in plasma calcidiol (25(OH)D). At 120 days-old (first day of calcium diet) there was no difference in body weight, food intake, body total fat and visceral fat. At 180 days-old, the EW animals were overweight, hyperphagia, higher total and visceral body fat, increased adipocyte area, higher leptin content in visceral adipose tissue, lower content of OBRb and SOCS3. There was an increase in serum levels of 25(OH)D, no change in 1,25(OH)2D levels and PTH. In liver, the EW animals had no change in Cyp2r1, SIRT1 and cholesterol, but showed lower VDR and PPARα, and increased triglyceride content. In kidney of the animals, had no difference in VDR expression, Cyp27b1/1α-Hydroxylase and Cyp24/24hydroxylase. In the gut, there was a lower calbindin and no change in VDR. In adipose tissue, EW animals had lower VDR expression and higher Cyp27b1/1α-hydroxylase expression, C/EBP-β, PPARg, IL-6, MCP1 and TNFα, and no change in IL1β and lower IL10. We observed no change in plasma inflammatory cytokines. We found higher TBARS and carbonyl in liver. The calcium supplemented diet normalized almost all disorders found in EW group. In 3T3L1 cells, 1,25(OH)2D incubation decreased CYP27B1/1α-hydroxylase and VDR expression, and despite higher VDR content; decreased cell proliferation with no change in apoptosis. The leptin incubation decreased CYP27B1/1α-hydroxylase; and the co-incubation decreased VDR expression with no change in CYP27B1/1α-hydroxylase. Early weaning leads to malnutrition and hypocalcemia, reflecting on changes in vitamin D metabolism/action, contributing to long-term to vitamin D resistance and higher adiposity, inflammation and oxidative stress. Dietary calcium supplementation during 2 months protect against the development of these disorders en EW group.