Adipose tissue vitamin D

An overview of selected papers related to bone published in 2017 is provided. PURPOSE: This paper accompanies a lecture at the 2018 Belgian Bone Club annual Clinical Update Symposium held in Brussels on January 20th, discussing the best papers (in the opinion of the author) published in the previous year. METHODS: A PubMed search using the keyword "bone" and articles published in 2017. RESULTS: Hot topics include screening for osteoporosis, novel anabolic drugs such as romosozumab and abaloparatide for osteoporosis and rare metabolic bone diseases, as well as long-term efficacy of denosumab and possible risk of multiple vertebral fractures following its discontinuation...

BACKGROUND: To what extent does the circulating 25-hydroxyvitamin D (25[OH]D) concentration help to meet the physiological needs of humans is an ongoing subject of debate. Remaining unexposed to the sun to reduce melanoma cancer risk, current lifestyle with less out door activities, and increasing obesity rates, which in turn increases the storage of vitamin D in the adipose tissue, are presumably factors that contribute to the substantial upsurge in the prevalence of vitamin D deficiency in humans...

OBJECTIVES: Lower vitamin D status has been associated with adiposity in children through adults. However, the evidence of the impact of maternal vitamin-D status during pregnancy on offspring's adiposity is mixed. The objective of this study was to examine the associations between maternal vitamin-D [25(OH)D] status at mid-gestation and neonatal abdominal adipose tissue (AAT) compartments, particularly the deep subcutaneous adipose tissue linked with metabolic risk. METHODS: Participants (N = 292) were Asian mother-neonate pairs from the mother-offspring cohort, Growing Up in Singapore Towards healthy Outcomes...

BACKGROUND/AIMS: Asian Indians have a high prevalence of vitamin D deficiency and metabolic syndrome. Vitamin D deficiency is associated with an increased risk of cardiovascular disease and diabetes. METHODS: We performed a cross-sectional study of 150 Asian Indians (50% male) from the San Francisco Bay Area. We assessed the association between 25-OH vitamin D (25-OHD) levels and vitamin D deficiency with body composition (anthropometric and radiographic measures) and metabolic outcomes...

Cancer cachexia, weight loss with altered body composition, is a multifactorial syndrome propagated by symptoms that impair caloric intake, tumor byproducts, chronic inflammation, altered metabolism, and hormonal abnormalities. Cachexia is associated with reduced performance status, decreased tolerance to chemotherapy, and increased mortality in cancer patients. Insulin resistance as a consequence of tumor byproducts, chronic inflammation, and endocrine dysfunction has been associated with weight loss in cancer patients...

BACKGROUND: The accumulation and pro-inflammatory polarization of immune cells, mainly macrophages, in adipose tissue (AT) are considered crucial factors for obesity-induced chronic inflammatory diseases. SCOPE OF REVIEW: In this review, we highlighted the role of adipose tissue macrophage (ATM) polarization on AT function in the obese state and the effect of the micro-environment and intracellular metabolism on the dynamic switch of ATMs into their pro-inflammatory or anti-inflammatory phenotypes, which may have distinct influences on obesity-related chronic inflammatory diseases...

The literature on thyroid autoimmunity has identified many potential factors at play for the initiation and progression of autoimmune thyroid diseases. These factors include genetic susceptibility, environmental factors, some drugs, iodine and selenium, infection, molecular mimics, and immune system defects. The sheer number of feasible factors makes sorting out the necessary agents from the fellow travelers difficult. In addition, many of these factors have the capability to interact-further confusing the picture...

Recently, we demonstrated high serum leptin and 25(OH)D (calcidiol) in obese animals, with high C/EBPβ and PPARγ expression in adipose tissue. Since the role of vitamin D in adipogenesis remains controversial and hyperleptinemia is found in obesity, we asked if leptin could interfere in vitamin D action on adipocytes. Here, we studied the direct effect of these two hormones upon 3T3L1 preadipocytes incubated with or without 1,25(OH)2D (100 nM, 24 h) and with leptin (10-7 M, 4 h later). RT-PCR (VDR and Cyp27b1/1α-hydroxylase), western blotting (VDR, Cyp27b1/1α-hydroxylase, ObR-b, C/EBPβ , PPARγ and Bax content), a cell proliferation assay and an Annexin V-FITC binding assay were performed...

To evaluate the effects of maternal vitamin D deficiency on body fat and adipogenesis in offspring rats, and explore the potential mechanism, we constructed a vitamin D deficient rat model and performed metabolic activity evaluation, body fat monitoring, biochemical analysis, adipogenesis assay, methylation microarray and RNA-seq for their offspring rats. We found the weight of vitamin D deficient (VDD) offspring was gradually higher than that of control (CLT) offspring, and the difference was significant since 10 weeks old...

SCOPE: Several studies have proposed a role of vitamin D in adipogenesis. Here, we sought to study the impact of the vitamin D receptor (Vdr) on adipocyte size in young and old mice and the effect of maternal vitamin D deficiency on fetal adipogenesis. METHODS AND RESULTS: Histological analysis of adipose tissues shows that Vdr knockout (KO) mice have smaller adipocytes than wild-type (WT) mice. Next, we compare young and old Vdr-KO and WT mice and find no differences in adipocyte sizes between weaned Vdr-KO and WT mice...

It is well established that the active form of vitamin D (i.e., 1,25-dihydroxyvitamin D [1,25(OH)2D]) regulates the expression of genes involved in its own metabolism and transport in the kidney and possibly in the liver. However, little is known about the transcriptional impact of cholecalciferol supplementation on white adipose tissue (WAT) and adipocytes, which are a major site of vitamin D and 25-hydroxyvitamin D [25(OH)D] storage in the organism. To fill this gap, we investigated the impact of cholecalciferol supplementation in WAT via a panel of genes coding for enzymes and proteins involved in vitamin D metabolism and uptake...

Subcutaneous white adipose tissue (scWAT) is the major fat depot in humans and is a central player in regulating whole body metabolism. Skin exposure to UV wavelengths from sunlight is required for Vitamin D synthesis and pigmentation, although it is plausible that longer visible wavelengths that penetrate the skin may regulate scWAT function. In this regard, we discovered a novel blue light-sensitive current in human scWAT that is mediated by melanopsin coupled to transient receptor potential canonical cation channels...

There is a high prevalence of vitamin D insufficiency and deficiency worldwide likely because of both limited sun-exposure and inadequate dietary intake. Meat, including pork, is not typically considered a dietary source of vitamin D, possibly because of management practices that raise pigs in confinement. This experiment determined the vitamin D content of loin and subcutaneous adipose tissue in sun-exposed finisher pigs. Two separate groups of pigs were used. The first group (28 white Landrace-Duroc) was assigned at random to either sunlight exposure (SUN) in spring and summer or confinement per standard practice (Control)...

Introduction Crosstalk between bone and adipose tissues is implicated in several pathologic conditions related to bone metabolism. Omentin-1, a 34-kD protein, is released from omental adipose tissue. A few studies indicated the effect of omentin-1 on bone health and bone mineral density (BMD) and the interaction of omentin-1 with vitamin D. Therefore, this study aimed to investigate the relationship between omentin-1, vitamin D, and BMD in postmenopausal women with osteoporosis compared with non-osteoporotic counterparts...

Adipose tissue has traditionally only been considered as an energy storage organ. Nevertheless, the importance of this tissue in systemic physiology and, especially, in systemic inflammation has been highlighted in recent years. Adipose tissue expresses proteins related to vitamin D (VD) metabolism, and it has been proposed that it can act as a VD storage tissue. The active form of VD, 1,25-dihydroxyvitamin D3 (1,25(OH)₂D₃), is able to modify adipocyte and adipose tissue physiology via the VD receptor (VDR), decreasing the expression of pro-inflammatory cytokines in adipose tissue...

Lysine succinylation, emerging as a novel post-translational modification, is closely related to the regulation of diverse biological processes, including many aspects of metabolism. Growing evidence suggests that low vitamin D status might exert an adverse impact on energy balance, adipogenesis and inflammation in white adipose tissue (WAT). However, whether there are any interactions between vitamin D and lysine succinylation still remains unknown. Here, combining high-affinity enrichment of lysine succinylated peptides with mass spectrometry and bioinformatics analysis, we reported the systematic profiling of the lysine succinylome, identifying 209 sites occurring on 159 proteins were up-regulated, 3 sites in 3 proteins were down-regulated in vitamin D receptor (VDR)-/- mice...

BACKGROUND AND AIM: Sarcopenia is a geriatric syndrome in which there is a decrease in muscle mass, muscle strength, and muscle function. Interleukin-15 (IL-15), a myokine released by skeletal muscle, has effects on both muscle and adipose tissue. We evaluated the relationship between plasma IL-15 level and sarcopenia. METHODS: We evaluated a total of 160 outpatient older people, and 80 of whom had sarcopenia. Sarcopenia was defined according to the European Working Group on Sarcopenia in Older People criteria...

Context: Vitamin D and 25-hydroxyvitamin D [25(OH)D] are stored in adipose tissue, but the clinical relevance is uncertain. Objective: To evaluate changes in serum 25(OH)D and adipose tissue vitamin D levels after stopping vitamin D supplementation. Design: A prospective, double-blind cohort follow-up study. Setting: Clinical Research Unit at University Hospital of North Norway. Patients: Seventy-six subjects were included after participation in a 3- to 5-year prevention of type 2 diabetes study and were administered 20,000 IU of vitamin D or placebo per week...

PURPOSE OF REVIEW: The possibility to use vitamin D supplementation to improve muscle wasting, with particular focus on cancer cachexia, is discussed. RECENT FINDINGS: Vitamin D exerts biological actions on myogenic precursor proliferation and differentiation, impinging on muscle regeneration. However, the effects of VitD supplementation in diseases associated with muscle atrophy, such as cancer cachexia, are poorly investigated. Data obtained in experimental models of cancer cachexia show that the administration of vitamin D to tumor-bearing animals is not able to prevent or delay both muscle wasting and adipose tissue depletion, despite increased expression of muscle vitamin D receptor...

Obese adolescents have increased fracture risk, but effects of alterations in adiposity on bone accrual and strength in obese adolescents are not understood. We evaluated 12-month changes in trabecular and cortical volumetric bone mineral density (vBMD) and cortical geometry in obese adolescents undergoing a randomized weight management program, and investigated the effect of body composition changes on bone outcomes. Peripheral quantitative computed tomography (pQCT) of the radius and tibia, and whole-body dual-energy X-ray absorptiometry (DXA) scans were obtained at baseline, 6 months, and 12 months in 91 obese adolescents randomized to standard care versus behavioral intervention for weight loss...