Deficiência de vitamina D e menopausa: efeitos no fígado e no tecido adiposo periovariano de camundongos

Abstract

In the present study, we have evaluated the impact of vitamin D deficiency in ovariectomized female mice. The hypothesis of our study is that vitamin D deficiency increases the inflammation in adipose tissue and promotes accumulation of hepatic fat in the menopause model. Female C57BL / 6 mice, three months old, were ovariectomized or not, and divided into control (C, fed control diet), ovariectomized (Ovx fed control diet), control without vitamin D (D-), fed control diet without vitamin D) and ovariectomized without vitamin D (Ovx (D-), fed control diet without vitamin D) for twelve weeks. As a result, in Ovx (D-) group there was insulin resistance and glucose intolerance, as well as an increase in body mass. In the liver, there was an increase in hepatic steatosis, with consequent increase in lipogenesis and inflammation due to the increase in the expression of genes and proteins of lipid metabolism. In addition, there was a reduction of beta-oxidation and reduction of fatty acid oxidation. In periovarian adipose tissue, ovariectomy increased the mean area of adipocytes and protein and gene expression of pro-inflammatory cytokines. Associated with the findings, there was increase in the local vitamin D metabolism, to compensate the deficiency of this vitamin. In conclusion, that current experimental findings are robust showing that ovariectomy and vitamin D dietary restriction in mice have additive adverse effects that lead to increased body mass, hepatic steatosis and insulin resistance. These findings are linked to increase of lipogenesis markers and decreased of beta-oxidation, predisposing to accumulation of fat in the liver, as well as increased inflammation in periovarian adipose tissue.