The Action of Vitamin D in Adipose Tissue: Is There the Link between Vitamin D Deficiency and Adipose Tissue-Related Metabolic Disorders?

Abstract

Adipose tissue plays an important role in systemic metabolism via the secretion of adipocytokines and storing and releasing energy. In obesity, adipose tissue becomes dysfunctional and characterized by hypertrophied adipocytes, increased inflammation, hypoxia, and decreased angiogenesis. Although adipose tissue is one of the major stores of vitamin D, its deficiency is detective in obese subjects. In the presented review, we show how vitamin D regulates numerous processes in adipose tissue and how their dysregulation leads to metabolic disorders. The molecular response to vitamin D in adipose tissue affects not only energy metabolism and adipokine and anti-inflammatory cytokine production via the regulation of gene expression but also genes participating in antioxidant defense, adipocytes differentiation, and apoptosis. Thus, its deficiency disturbs adipocytokines secretion, metabolism, lipid storage, adipogenesis, thermogenesis, the regulation of inflammation, and oxidative stress balance. Restoring the proper functionality of adipose tissue in overweight or obese subjects is of particular importance in order to reduce the risk of developing obesity-related complications, such as cardiovascular diseases and diabetes. Taking into account the results of experimental studies, it seemed that vitamin D may be a remedy for adipose tissue dysfunction, but the results of the clinical trials are not consistent, as some of them show improvement and others no effect of this vitamin on metabolic and insulin resistance parameters. Therefore, further studies are required to evaluate the beneficial effects of vitamin D, especially in overweight and obese subjects, due to the presence of a volumetric dilution of this vitamin among them.

Vitamin D and Obesity/Adiposity—A Brief Overview of Recent Studies

“…For some years now, VD has attracted increasing attention due to the resurgence of VD deficiency in children and adults worldwide [ 2 , 3 , 4 ] and its suspected multiple extraskeletal benefits, including for cardiometabolic health [ 1 , 5 ]. In the cardiometabolic context, a huge number of in vitro experiments have clearly mapped out the actions of vitamin D on key parameters of adipose tissue and adipocyte biology including adipogenesis and the regulation of gene expression in response to energy homeostasis and inflammation (see [ 6 , 7 , 8 ] for reviews). These lines of evidence all converge towards a beneficial role of vitamin D in the physiology of adipose tissue, prompting a massive body of research attempting to unravel the relationship between vitamin D and obesity/adiposity in humans and in animals.…”

Lifestyle and health of individuals with multiple sclerosis according to body mass index: initial results

“…Among the participants in our study, the overweight and obese individuals showed a significantly lower vitamin D concentration compared to the normal-weight individuals, despite the lack of corresponding differences in the use of supplementation. This was probably due to the fact that obesity usually leads to a decreased bioavailability of vitamin D because its active form is stored and degraded in the adipose tissue [35]. Biotin is a vitamin that is engaged in the synthesis of myelin.…”

Vitamin D and Visceral Obesity in Humans: What Should Clinicians Know?

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