Supplementing alpha-tocopherol (vitamin E) and vitamin D3 in high fat diet decrease IL-6 production in murine epididymal adipose tissue and 3T3-L1 adipocytes following LPS stimulation

Multifaceted Roles of Vitamin D for Diabetes: From Immunomodulatory Functions to Metabolic Regulations

Numerous studies have established associations between vitamin D and diabetes. The vitamin D receptor is widely distributed throughout the human body, including in pancreatic beta cells (β-cells), hepatocytes, and immune cells. Therefore, vitamin D's effect on the risk, progression, or complications of diabetes may be mediated through various mechanisms. These include the regulation of insulin secretion or sensitivity and modulation of β-cell function and its immunomodulatory and anti-inflammatory effects. This review extensively explores the relationship between vitamin D status and diabetes, as well as the preventive or therapeutic effects of vitamin D supplementation on diabetes from human studies. Additionally, it examines in detail the impact of vitamin D on immune and inflammatory responses in the diabetic milieux and β-cell function to better understand the underlying mechanisms through which vitamin D influences diabetes.

Genetic Factors Contributing to Interindividual Variability of α-Tocopherol Levels in Subcutaneous Adipose Tissue among Healthy Adult Males

In humans, α-tocopherol (α-TOC) is mainly stored in adipose tissue, where it participates in preventing damages induced by inflammation and reactive oxygen species. Factors, including genetic ones, that explain adipose tissue α-TOC concentration remain poorly understood. This study, therefore, aimed to characterize the interindividual variability of adipose tissue α-TOC concentration in healthy individuals and to identify single nucleotide polymorphisms (SNPs) associated with it. The study used a randomized cross-over design with 42 healthy adult males. α-TOC concentration was measured in fasting plasma and periumbilical adipose tissue samples, both at fast and 8 h after consumption of three standard meals. Partial least squares (PLS) regression was performed to identify SNPs associated with the interindividual variability of adipose tissue α-TOC concentration. Adipose tissue α-TOC concentration was not associated with fasting plasma concentration (Pearson's r = 0.24, 95% CI: [-0.08, 0.51]). There was a high interindividual variability of adipose tissue α-TOC concentration (CV = 61%). A PLS regression model comprising 10 SNPs in five genes (PPARG, ABCA1, BUD13, CD36, and MGLL) explained 60% (adjusted R2) of the variability of this concentration. The interindividual variability of adipose tissue α-TOC concentration in humans is due, at least partly, to SNPs in genes involved in α-TOC and triglyceride metabolism.

Vitamin 25(OH)D3, E, and C Supplementation Impact the Inflammatory and Antioxidant Responses in Piglets Fed a Deoxynivalenol-Contaminated Diet and Challenged with Lipopolysaccharides

Using alternative ingredients or low-quality grain grades to reduce feeding costs for pig diets can introduce mycotoxins such as deoxynivalenol (DON) into feed, which is known to induce anorexia, inflammation, and oxidative stress. Adding vitamin 25(OH)D3 or vitamins E and C to the feed could increase piglets' immune system to alleviate the effects of DON. This study used 54 pigs (7.8 ± 0.14 kg) in 27 pens (2 pigs/pen) with a vitamin 25(OH)D3 or vitamin E-C supplementation, or their combination, in DON-contaminated (5.1 mg/kg) feed ingredients over 21 days followed by a lipopolysaccharide (LPS) challenge (20 µg/kg BW) 3 h prior to euthanasia for 1 piglet per pen. DON contamination induced anorexia, which reduced piglet growth. DON also induced immunomodulation, oxidative stress, and downregulated vitamin D status. The vitamin E and C supplementation and the combination of vitamins E, C, and 25(OH)D3 provided protection against DON contamination by not only decreasing blood and liver oxidative stress markers, but also by increasing antioxidant enzymes and tocopherol levels in blood, indicating improved antioxidant defense mechanisms. The combination of vitamins also restored the vitamin D status. After LPS challenge, DON contamination decreased intestinal and liver antioxidant statuses and increased inflammation markers. The addition of vitamins E and C to DON-contaminated feed reduced markers of inflammation and improved the antioxidant status after the LPS immune stimulation. The combination of all these vitamins also reduced the oxidative stress markers and the inflammation in the intestine and mesenteric lymph nodes, suggesting an anti-inflammatory effect.

Vitamin D in Diabetes: Uncovering the Sunshine Hormone's Role in Glucose Metabolism and Beyond

Over the last decades, epidemiology and functional studies have started to reveal a pivotal role of vitamin D in both type 1 and type 2 diabetes pathogenesis. Acting through the vitamin D receptor (VDR), vitamin D regulates insulin secretion in pancreatic islets and insulin sensitivity in multiple peripheral metabolic organs. In vitro studies and both T1D and T2D animal models showed that vitamin D can improve glucose homeostasis by enhancing insulin secretion, reducing inflammation, reducing autoimmunity, preserving beta cell mass, and sensitizing insulin action. Conversely, vitamin D deficiency has been shown relevant in increasing T1D and T2D incidence. While clinical trials testing the hypothesis that vitamin D improves glycemia in T2D have shown conflicting results, subgroup and meta-analyses support the idea that raising serum vitamin D levels may reduce the progression from prediabetes to T2D. In this review, we summarize current knowledge on the molecular mechanisms of vitamin D in insulin secretion, insulin sensitivity, and immunity, as well as the observational and interventional human studies investigating the use of vitamin D as a treatment for diabetes.

Adipose Tissue Aging and Metabolic Disorder, and the Impact of Nutritional Interventions

Adipose tissue is the largest and most active endocrine organ, involved in regulating energy balance, glucose and lipid homeostasis and immune function. Adipose tissue aging processes are associated with brown adipose tissue whitening, white adipose tissue redistribution and ectopic deposition, resulting in an increase in age-related inflammatory factors, which then trigger a variety of metabolic syndromes, including diabetes and hyperlipidemia. Metabolic syndrome, in turn, is associated with increased inflammatory factors, all-cause mortality and cognitive impairment. There is a growing interest in the role of nutritional interventions in adipose tissue aging. Nowadays, research has confirmed that nutritional interventions, involving caloric restriction and the use of vitamins, resveratrol and other active substances, are effective in managing adipose tissue aging’s adverse effects, such as obesity. In this review we summarized age-related physiological characteristics of adipose tissue, and focused on what nutritional interventions can do in improving the retrogradation and how they do this.

A Hyaluronic Acid-Based Formulation with Simultaneous Local Drug Delivery and Antioxidant Ability for Active Viscosupplementation

Hyaluronic acid (HA) and its derivatives are widely used for intra-articular injection to augment compromised viscoelastic properties of damaged synovial fluid. Combining HA-based devices with anti-inflammatory drugs or bioactive principles in order to provide an additional benefit to the viscosupplementation is emerging as a new promising approach to improve the clinical outcome. Here, we aim to design a novel active viscosupplementation agent that can load and release hydrophobic drugs and at the same time possessing antioxidant properties. Optimized ternary systems named HCV based on HA, (2-hydroxypropyl)-β-cyclodextrin (CD), and vitamin E (VE), without being engaged in formal chemical bonding with each other, showed the best viscoelastic and lubrication properties along with antioxidant capabilities, able to solubilize and release DF. The physical-chemical characterization suggested that the HCV system displayed rheological synergism and higher thermal stability because of the presence of VE and its antioxidant activity, and the loading of hydrophobic drugs was improved by the presence of CD and VE. Cell morphology and viability tests on L929 cells exhibited high biocompatibility of the HCV system with higher level expression of anti-inflammatory interleukin-10.

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

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.

A Novel Multi-Ingredient Supplement Activates a Browning Program in White Adipose Tissue and Mitigates Weight Gain in High-Fat Diet-Fed Mice

We investigated the effects of a novel multi-ingredient supplement comprised of polyphenol antioxidants and compounds known to facilitate mitochondrial function and metabolic enhancement (ME) in a mouse model of obesity. In this study, 6-week-old male C57/BL6J mice were placed on a high-fat diet (HFD; ~60% fat) for 6 weeks, with subsequent allocation into experimentalgroups for 4 weeks: HFD control, HFD + ME10 (10 components), HFD + ME7 (7 components), HFD + ME10 + EX, HFD + EX (where '+EX' animals exercised 3 days/week), and chow-fed control. After the intervention, HFD control animals had significantly greater body weight and fat mass. Despite the continuation of HFD, animals supplemented with multi-ingredient ME or who performed exercise training showed an attenuation of fat mass and preservation of lean body mass, which was further enhanced when combined (ME+EX). ME supplementation stimulated the upregulation of white and brown adipose tissue mRNA transcripts associated with mitochondrial biogenesis, browning, fatty acid transport, and fat metabolism. In WAT depots, this was mirrored by mitochodrial oxidative phosphorylation (OXPHOS) protein expression, and increased in vivo fat oxidation measured via CLAMS. ME supplementation also decreased systemic and local inflammation markers. Herein, we demonstrated that novel multi-ingredient nutritional supplements induced significant fat loss independent of physical activity while preserving muscle mass in obese mice. Mechanistically, these MEs appear to act by inducing a browning program in white adipose tissue and decreasing other pathophysiological impairments associated with obesity, including mitochondrial respiration alterations induced by HFD.

Association of EDARV370A with breast density and metabolic syndrome in Latinos

The ectodysplasin receptor (EDAR) is a tumor necrosis factor receptor (TNF) superfamily member. A substitution in an exon of EDAR at position 370 (EDARV370A) creates a gain of function mutant present at high frequencies in Asian and Indigenous American populations but absent in others. Its frequency is intermediate in populations of Mexican ancestry. EDAR regulates the development of ectodermal tissues, including mammary ducts. Obesity and type 2 diabetes mellitus are prevalent in people with Indigenous and Latino ancestry. Latino patients also have altered prevalence and presentation of breast cancer. It is unknown whether EDARV370A might connect these phenomena. The goals of this study were to determine 1) whether EDARV370A is associated with metabolic phenotypes and 2) if there is altered breast anatomy in women carrying EDARV370A. Participants were from two Latino cohorts, the Arizona Insulin Resistance (AIR) registry and Sangre por Salud (SPS) biobank. The frequency of EDARV370A was 47% in the Latino cohorts. In the AIR registry, carriers of EDARV370A (GG homozygous) had significantly (p < 0.05) higher plasma triglycerides, VLDL, ALT, 2-hour post-challenge glucose, and a higher prevalence of prediabetes/diabetes. In a subset of the AIR registry, serum levels of ectodysplasin A2 (EDA-A2) also were associated with HbA1c and prediabetes (p < 0.05). For the SPS biobank, participants that were carriers of EDARV370A had lower breast density and higher HbA1c (both p < 0.05). The significant associations with measures of glycemia remained when the cohorts were combined. We conclude that EDARV370A is associated with characteristics of the metabolic syndrome and breast density in Latinos.

Untargeted Metabolomics Analysis Revealed Lipometabolic Disorders in Perirenal Adipose Tissue of Rabbits Subject to a High-Fat Diet

Simply Summary

A high-fat diet is widely recognized as a significant modifiable risk for metabolic diseases. In this study, untargeted metabolomics, combined with liquid chromatography and high-resolution mass spectrometry, was used to evaluate perirenal adipose tissue metabolic changes. Our study revealed 206 differential metabolites. These metabolites were mainly associated with the biosynthesis of unsaturated fatty acids, the arachidonic acid metabolic pathway, the ovarian steroidogenesis pathway, and the platelet activation pathway. Our study revealed that a high-fat diet causes significant lipometabolic disorders; these metabolites may inhibit oxygen respiration by increasing adipocytes cells and density, cause mitochondrial and endoplasmic reticulum dysfunction, produce inflammation, and finally lead to insulin resistance, thereby increasing the risk of Type 2 diabetes, atherosclerosis, and other metabolic syndromes.

Abstract

A high-fat diet (HFD) is widely recognized as a significant modifiable risk for insulin resistance, inflammation, Type 2 diabetes, atherosclerosis and other metabolic diseases. However, the biological mechanism responsible for key metabolic disorders in the PAT of rabbits subject to HFD remains unclear. Here, untargeted metabolomics (LC-MS/MS) combined with liquid chromatography (LC) and high-resolution mass spectrometry (MS) were used to evaluate PAT metabolic changes. Histological observations showed that the adipocytes cells and density of PAT were significantly increased in HFD rabbits. Our study revealed 206 differential metabolites (21 up-regulated and 185 down-regulated); 47 differential metabolites (13 up-regulated and 34 down-regulated), comprising mainly phospholipids, fatty acids, steroid hormones and amino acids, were chosen as potential biomarkers to help explain metabolic disorders caused by HFD. These metabolites were mainly associated with the biosynthesis of unsaturated fatty acids, the arachidonic acid metabolic pathway, the ovarian steroidogenesis pathway, and the platelet activation pathway. Our study revealed that a HFD caused significant lipometabolic disorders. These metabolites may inhibit oxygen respiration by increasing the adipocytes cells and density, cause mitochondrial and endoplasmic reticulum dysfunction, produce inflammation, and finally lead to insulin resistance, thus increasing the risk of Type 2 diabetes, atherosclerosis, and other metabolic syndromes.

The Role of Vitamin D in Adipose Tissue Biology: Adipocyte Differentiation, Energy Metabolism, and Inflammation

Adipose tissue is composed of diverse cell types and plays a major role in energy homeostasis and inflammation at the local and systemic levels. Adipose tissue serves as the main site for vitamin D storage and is among the most important extraskeletal targets of vitamin D which can modulate multiple aspects of adipose tissue biology. Vitamin D may exert inhibitory or stimulatory effects on adipocyte differentiation depending on cell type, stage of differentiation, and the treatment time point. Moreover, vitamin D controls energy metabolism in adipose tissue by affecting fatty acid oxidation, expression of uncoupling proteins, insulin resistance, and adipokine production. Adipose tissue inflammation can have a significant impact on the metabolic disorders often associated with obesity, and vitamin D can modulate the inflammatory response of immune cells and adipocytes within the adipose tissue. This review discusses the role of adipose tissue in vitamin D metabolism, as well as the regulatory role of vitamin D in adipocyte differentiation, adipose tissue energy metabolism, and inflammation, thereby providing insights into the importance of vitamin D in adipose tissue biology.

Insulin resistance: a connecting link between Alzheimer's disease and metabolic disorder

Recent evidence suggests that Alzheimer's disease (AD) is closely linked with insulin resistance, as seen in type 2 diabetes mellitus (T2DM). Insulin signaling is impaired in AD brains due to insulin resistance, ultimately resulting in the formation of neurofibrillary tangles (NFTs). AD and T2DM are connected at molecular, clinical, and epidemiological levels making it imperative to understand the contribution of T2DM, and other metabolic disorders, to AD pathogenesis. In this review, we have discussed various modalities involved in the pathogenesis of these two diseases and explained the contributing parameters. Insulin is vital for maintaining glucose homeostasis and it plays an important role in regulating inflammation. Here, we have discussed the roles of various contributing factors like miRNA, leptin hormone, neuroinflammation, metabolic dysfunction, and gangliosides in insulin impairment both in AD and T2DM. Understanding these mechanisms will be a big step forward for making molecular therapies that may help maintain or prevent both AD and T2DM, thus reducing the burden of both these diseases.

Associations Between Different Dietary Vitamins and the Risk of Obesity in Children and Adolescents: A Machine Learning Approach

BACKGROUNDS

Simultaneous dietary intake of vitamins is considered as a common and real scenario in daily life. However, limited prospective studies have evaluated the association between multivitamins intake and obesity in children and adolescents.

OBJECTIVES

This study aimed to evaluate the relationship between the intake of different dietary vitamins and the risk of obesity in children (6-11 years) and adolescents (12-19 years).

METHODS

We conducted a cross-sectional study based on data from U.S. National Health and Nutrition Examination Survey, 2013-2016. A total of 3634 children and adolescents were included who had available data on dietary vitamins, obesity and covariates. We analyzed the dietary intake levels of nine vitamins, including vitamin A, vitamin B₁, vitamin B₂, vitamin B₆, vitamin B₁₂, vitamin C, vitamin D, vitamin E, vitamin K. Multivariate logistic regression was used to model the associations between vitamins and obesity. Bayesian kernel machine regression (BKMR) was employed to explore the joint and independent effects of vitamins on obesity among children and adolescents.

RESULTS

In the multivariate logistic regression model, five vitamins (vitamin A, vitamin B₁, vitamin B₂, vitamin B₁₂, and vitamin D) were negatively associated with obesity in children and adolescents. BKMR analysis showed that when the concentration of the nine vitamins was at or above the 55th percentile compared with the median value, the combined intake of these vitamins could significantly reduce the risk of obesity in children and adolescents. Potential interactions between vitamin B₂ and vitamin B₁₂ in increasing the risk of obesity in children and adolescents were observed.

CONCLUSIONS

We determine the combined effects of multivitamins on obesity in children and adolescents, and observe a significant interaction between vitamin B₂ and vitamin B₁₂. Further cohort studies are needed to clarify the health effects of multivitamins intake in a larger population.

Low doses of eriocitrin attenuate metabolic impairment of glucose and lipids in ongoing obesogenic diet in mice

Eriocitrin is a citrus flavonoid with a high capacity to reduce the oxidative stress related to metabolic disorders and obesity. We assessed the effects of low doses of eriocitrin on the oxidative stress, inflammation, and metabolism of glucose and lipids of high-fat diet (HFD)-fed obese mice. Fifty male C57BL/6J mice were randomly assigned into five groups (n 10). The mice were fed an HFD (45 % kcal from fat, i.e. lard) for 4 weeks for obesity induction. After this period, the mice continued receiving the same HFD, but supplemented with eriocitrin at 10, 25 or 100 mg/kg body weight (bw) for an additional 4 weeks. Control groups were fed with standard diet (10 % kcal of fat, i.e. soy oil) or with HFD without eriocitrin, for eight consecutive weeks. At the end of the study, mice supplemented with eriocitrin showed lower levels of blood serum glucose and blood and liver triacylglycerols (P < 0⋅05). There was also improved levels of insulin, HOMA-IR, total-cholesterol, resistin and lipid peroxidation in the supplemented mice. It was concluded that the 25 mg dose of eriocitrin improved all the parameters studied and had positive effects on oxidative stress, systemic inflammation and metabolism of lipids and glucose in general.

The Molecular Mechanisms by Which Vitamin D Prevents Insulin Resistance and Associated Disorders

Numerous studies have shown that vitamin D deficiency is very common in modern societies and is perceived as an important risk factor in the development of insulin resistance and related diseases such as obesity and type 2 diabetes (T2DM). While it is generally accepted that vitamin D is a regulator of bone homeostasis, its ability to counteract insulin resistance is subject to debate. The goal of this communication is to review the molecular mechanism by which vitamin D reduces insulin resistance and related complications. The university library, PUBMED, and Google Scholar were searched to find relevant studies to be summarized in this review article. Insulin resistance is accompanied by chronic hyperglycaemia and inflammation. Recent studies have shown that vitamin D exhibits indirect antioxidative properties and participates in the maintenance of normal resting ROS level. Appealingly, vitamin D reduces inflammation and regulates Ca²⁺ level in many cell types. Therefore, the beneficial actions of vitamin D include diminished insulin resistance which is observed as an improvement of glucose and lipid metabolism in insulin-sensitive tissues.

Vitamin D ameliorates adipose browning in chronic kidney disease cachexia

Patients with chronic kidney disease (CKD) are often 25(OH)D3 and 1,25(OH)2D3 insufficient. We studied whether vitamin D repletion could correct aberrant adipose tissue and muscle metabolism in a mouse model of CKD-associated cachexia. Intraperitoneal administration of 25(OH)D3 and 1,25(OH)2D3 (75 μg/kg/day and 60 ng/kg/day respectively for 6 weeks) normalized serum concentrations of 25(OH)D3 and 1,25(OH)2D3 in CKD mice. Vitamin D repletion stimulated appetite, normalized weight gain, and improved fat and lean mass content in CKD mice. Vitamin D supplementation attenuated expression of key molecules involved in adipose tissue browning and ameliorated expression of thermogenic genes in adipose tissue and skeletal muscle in CKD mice. Furthermore, repletion of vitamin D improved skeletal muscle fiber size and in vivo muscle function, normalized muscle collagen content and attenuated muscle fat infiltration as well as pathogenetic molecular pathways related to muscle mass regulation in CKD mice. RNAseq analysis was performed on the gastrocnemius muscle. Ingenuity Pathway Analysis revealed that the top 12 differentially expressed genes in CKD were correlated with impaired muscle and neuron regeneration, enhanced muscle thermogenesis and fibrosis. Importantly, vitamin D repletion normalized the expression of those 12 genes in CKD mice. Vitamin D repletion may be an effective therapeutic strategy for adipose tissue browning and muscle wasting in CKD patients.

Therapeutic Efficacy of Antioxidants in Ameliorating Obesity Phenotype and Associated Comorbidities

Obesity has been a worldwide epidemic for decades. Despite the abundant increase in knowledge regarding the etiology and pathogenesis of obesity, the prevalence continues to rise with estimates predicting considerably higher numbers by the year 2030. Obesity is characterized by an abnormal lipid accumulation, however, the physiological consequences of obesity are far more concerning. The development of the obesity phenotype constitutes dramatic alterations in adipocytes, along with several other cellular mechanisms which causes substantial increase in systemic oxidative stress mediated by reactive oxygen species (ROS). These alterations promote a chronic state of inflammation in the body caused by the redox imbalance. Together, the systemic oxidative stress and chronic inflammation plays a vital role in maintaining the obese state and exacerbating onset of cardiovascular complications, Type II diabetes mellitus, dyslipidemia, non-alcoholic steatohepatitis, and other conditions where obesity has been linked as a significant risk factor. Because of the apparent role of oxidative stress in the pathogenesis of obesity, there has been a growing interest in attenuating the pro-oxidant state in obesity. Hence, this review aims to highlight the therapeutic role of antioxidants, agents that negate pro-oxidant state of cells, in ameliorating obesity and associated comorbidities. More specifically, this review will explore how various antioxidants target unique and diverse pathways to exhibit an antioxidant defense mechanism.

Effects of 1,25-dihydroxyvitamin D3 on the Inflammatory Responses of Stromal Vascular Cells and Adipocytes from Lean and Obese Mice

Vitamin D status has been implicated in obesity and adipose tissue inflammation. In the present study, we explored the effects of dietary vitamin D supplementation on adipose tissue inflammation and immune cell population, and the effects of in vitro 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) treatment on pro-inflammatory cytokine production by stromal vascular cells (SVCs) and adipocytes in lean and high-fat diet-induced obese mice. The results show that epididymal fat Mcp-1 and Rantes mRNA levels, which were higher in obese mice compared with lean mice, were significantly down-regulated by vitamin D supplementation. While obese mice had higher numbers of macrophages and natural killer (NK) cells within adipose tissue, these remained unaltered by vitamin D supplementation. In accordance with these in vivo findings, the in vitro 1,25(OH)2D3 treatment decreased IL-6, MCP-1, and IL-1β production by SVCs from obese mice, but not by adipocytes. In addition, 1,25(OH)2D3 treatment significantly decreased Tlr2 expression and increased mRNA levels of Iκba and Dusp1 in SVCs. These findings suggest that vitamin D supplementation attenuates inflammatory response in adipose tissue, especially in SVCs, possibly through inhibiting NF-κB and MAPK signaling pathways in SVCs but not by the inhibition of macrophage infiltration.

Chronic vitamin D insufficiency impairs physical performance in C57BL/6J mice

Vitamin D insufficiency (serum 25-OH vitamin D < 30 ng/ml) affects 70-80% of the general population, yet the long-term impacts on physical performance and the progression of sarcopenia are poorly understood. We therefore followed 6-month-old male C57BL/6J mice (n=6) consuming either sufficient (STD, 1000 IU) or insufficient (LOW, 125 IU) vitamin D3/kg chow for 12 months (equivalent to 20-30 human years). LOW supplemented mice exhibited a rapid decline of serum 25-OH vitamin D levels by two weeks that remained between 11-15 ng/mL for all time points thereafter. After 12 months LOW mice displayed worse grip endurance (34.6 ± 14.1 versus 147.5 ± 50.6 seconds, p=0.001), uphill sprint speed (16.0 ± 1.0 versus 21.8 ± 2.4 meters/min, p=0.0007), and stride length (4.4 ± 0.3 versus 5.1 ± 0.3, p=0.002). LOW mice also showed less lean body mass after 8 months (57.5% ± 5.1% versus 64.5% ± 4.0%, p=0.023), but not after 12 months of supplementation, as well as greater protein expression of atrophy pathway gene atrogin‑1. Additionally, microRNA sequencing revealed differential expression of mIR‑26a in muscle tissue of LOW mice. These data suggest chronic vitamin D insufficiency may be an important factor contributing to functional decline and sarcopenia.

Linking the metabolic syndrome and obesity with vitamin D status: risks and opportunities for improving cardiometabolic health and well-being

The global death toll from noncommunicable diseases is exceptionally high, reported to cause 71% of global deaths worldwide. Metabolic syndrome risk factors, especially excessive adiposity and obesity, are at the heart of the problem resulting in increased co-morbidities such as cardiometabolic diseases and cancer, increased health costs, poorer quality of life, and shortened survival. Vitamin D3 can positively reverse many of these adverse effects and outcomes through blocking signaling mechanisms that predispose to cardiometabolic and metastatic disease. As an affordable natural agent, vitamin D3 can be used to counteract obesity-induced inflammation, block early adipogenesis, enhance glucose uptake, counteract hyperleptinemia, ameliorate insulin resistance, and reduce hypertension. This is supported by data from in vitro, in vivo and epidemiological studies and clinical trials. We propose that everyone in general and obese patients in particular consider raising 25-hydroxyvitamin D levels through UVB exposure and/or supplemental vitamin D3 intake to reduce cardiometabolic and metastatic disease and increase longevity.

Role of epigenetics in transformation of inflammation into colorectal cancer

Molecular mechanisms associated with inflammation-promoted tumorigenesis have become an important topic in cancer research. Various abnormal epigenetic changes, including DNA methylation, histone modification, chromatin remodeling, and noncoding RNA regulation, occur during the transformation of chronic inflammation into colorectal cancer (CRC). These changes not only accelerate transformation but also lead to cancer progression and metastasis by activating carcinogenic signaling pathways. The NF-κB and STAT3 signaling pathways play a particularly important role in the transformation of inflammation into CRC, and both are critical to cellular signal transduction and constantly activated in cancer by various abnormal changes including epigenetics. The NF-κB and STAT3 signals contribute to the microenvironment for tumorigenesis through secretion of a large number of pro-inflammatory cytokines and their crosstalk in the nucleus makes it even more difficult to treat CRC. Compared with gene mutation that is irreversible, epigenetic inheritance is reversible or can be altered by the intervention. Therefore, understanding the role of epigenetic inheritance in the inflammation-cancer transformation may elucidate the pathogenesis of CRC and promote the development of innovative drugs targeting transformation to prevent and treat this malignancy. This review summarizes the literature on the roles of epigenetic mechanisms in the occurrence and development of inflammation-induced CRC. Exploring the role of epigenetics in the transformation of inflammation into CRC may help stimulate futures studies on the role of molecular therapy in CRC.

Analysis of Association between Vitamin D Deficiency and Insulin Resistance

Recent evidence revealed extra skeleton activity of vitamin D, including prevention from cardiometabolic diseases and cancer development as well as anti-inflammatory properties. It is worth noting that vitamin D deficiency is very common and may be associated with the pathogenesis of insulin-resistance-related diseases, including obesity and diabetes. This review aims to provide molecular mechanisms showing how vitamin D deficiency may be involved in the insulin resistance formation. The PUBMED database and published reference lists were searched to find studies published between 1980 and 2019. It was identified that molecular action of vitamin D is involved in maintaining the normal resting levels of ROS and Ca2+, not only in pancreatic β-cells, but also in insulin responsive tissues. Both genomic and non-genomic action of vitamin D is directed towards insulin signaling. Thereby, vitamin D reduces the extent of pathologies associated with insulin resistance such as oxidative stress and inflammation. More recently, it was also shown that vitamin D prevents epigenetic alterations associated with insulin resistance and diabetes. In conclusion, vitamin D deficiency is one of the factors accelerating insulin resistance formation. The results of basic and clinical research support beneficial action of vitamin D in the reduction of insulin resistance and related pathologies.

The effect of chronic oral vitamin D supplementation on adiposity and insulin secretion in hypothalamic obese rats

Reduced plasma vitamin D (VD) levels may contribute to excessive white adipose tissue, insulin resistance (IR) and dyslipidaemia. We evaluated the effect of chronic oral VD supplementation on adiposity and insulin secretion in monosodium glutamate (MSG)-treated rats. During their first 5 d of life, male neonate rats received subcutaneous injections of MSG (4 g/kg), while the control (CON) group received saline solution. After weaning, groups were randomly distributed into VD supplemented (12 µg/kg; three times/week) and non-supplemented (NS) rats, forming four experimental groups (n 15 rats/group): CON-NS, CON-VD, MSG-NS and MSG-VD. At 76 d of life, rats were submitted to an oral glucose tolerance test (OGTT; 2 g/kg), and at 86 d, obesity, IR and plasma metabolic parameters were evaluated. Pancreatic islets were isolated for glucose-induced insulin secretion (GIIS), cholinergic insulinotropic response and muscarinic 3 receptor (M3R), protein kinase C (PKC) and protein kinase A (PKA) expressions. Pancreas was submitted to histological analyses. VD supplementation decreased hyperinsulinaemia (86 %), hypertriacylglycerolaemia (50 %) and restored insulin sensibility (89 %) in MSG-VD rats, without modifying adiposity, OGTT or GIIS, compared with the MSG-NS group. The cholinergic action was reduced (57 %) in islets from MSG-VD rats, without any change in M3R, PKA or PKC expression. In conclusion, chronic oral VD supplementation of MSG-obese rats was able to prevent hyperinsulinaemia and IR, improving triacylglycerolaemia without modifying adiposity. A reduced cholinergic pancreatic effect, in response to VD, could be involved in the normalisation of plasma insulin levels, an event that appears to be independent of M3R and its downstream pathways.

The Role of Tocotrienol in Protecting Against Metabolic Diseases

Obesity is a major risk factor for diabetes, and these two metabolic conditions cause significant healthcare burden worldwide. Chronic inflammation and increased oxidative stress due to exposure of cells to excess nutrients in obesity may trigger insulin resistance and pancreatic β-cell dysfunction. Tocotrienol, as a functional food component with anti-inflammatory, antioxidant, and cell signaling-mediating effects, may be a potential agent to complement the current management of obesity and diabetes. The review aimed to summarize the current evidence on the anti-obesity and antidiabetic effects of tocotrienol. Previous studies showed that tocotrienol could suppress adipogenesis and, subsequently, reduce body weight and fat mass in animals. This was achieved by regulating pathways of lipid metabolism and fatty acid biosynthesis. It could also reduce the expression of transcription factors regulating adipogenesis and increase apoptosis of adipocytes. In diabetic models, tocotrienol was shown to improve glucose homeostasis. Activation of peroxisome proliferator-activated receptors was suggested to be responsible for these effects. Tocotrienol also prevented multiple systemic complications due to obesity and diabetes in animal models through suppression of inflammation and oxidative stress. Several clinical trials have been conducted to validate the antidiabetic of tocotrienol, but the results were heterogeneous. There is no evidence showing the anti-obesity effects of tocotrienol in humans. Considering the limitations of the current studies, tocotrienol has the potential to be a functional food component to aid in the management of patients with obesity and diabetes.

1α,25(OH)2D3 attenuates IL-6 and IL-1β-mediated inflammatory responses in macrophage conditioned medium-stimulated human white preadipocytes by modulating p44/42 MAPK and NF-κB signaling pathways

BACKGROUND

Metabolic syndrome is characterized by macrophage infiltration and inflammatory responses-metaflammation in adipose tissue. IL-6 and IL-1β could mediate the inflammatory responses in macrophage stimulated-preadipocytes by modulating MAPK and NF-κB pathways. To test this hypothesis we used antibodies to block IL-6 and IL-1β action in macrophage conditioned medium (MacCM)-stimulated human white preadipocytes. Moreover, as interventions that prevent this could potentially be used to treat or prevent metabolic syndrome, and 1α,25(OH)₂D₃ has previously been reported to exert an anti-inflammatory action on macrophage-stimulated adipocytes, in this study we also investigated whether 1α,25(OH)₂D₃ could attenuate inflammatory responses in MacCM-stimulated preadipocytes, and explored the potential anti-inflammatory mechanisms.

METHODS

Human white preadipocytes were cultured with 25% MacCM for 24 h to elicit inflammatory responses. This was confirmed by measuring the concentrations and mRNA levels of major pro-inflammatory factors [IL-1β, IL-6, IL-8, monocyte chemoattractant protein (MCP)-1 and regulated on activation, normal T cell expressed and secreted (RANTES)] by ELISA and qPCR, respectively. IL-6 and IL-1β actions were blocked using IL-6 antibody (300 ng/ml) and IL-1β antibody (15 μg/ml), respectively. Potential anti-inflammatory effects of 1α,25(OH)₂D₃ were investigated by pre-treatment and treatment of 1α,25(OH)₂D₃ (0.01 to 10 nM) for 48 h in MacCM-stimulated preadipocytes. In parallel, western blotting was used to determine inflammatory signaling molecules including relA of the NF-κB pathway and p44/42 MAPK modified during these processes.

RESULTS

MacCM enhanced the secretion and gene expression of IL-1β, IL-6, IL-8, MCP-1 and RANTES by increasing the phosphorylation levels of relA and p44/42 MAPK in preadipocytes, whereas blocking IL-6 and IL-1β action inhibited the inflammatory responses by decreasing p44/42 MAPK and relA phosphorylation, respectively. Furthermore, 10 nM of 1α,25(OH)₂D₃ generally inhibited the IL-6 and IL-1β-mediated inflammatory responses, and reduced both p44/42 MAPK and relA phosphorylation in MacCM-stimulated preadipocytes.

CONCLUSIONS

1α,25(OH)₂D₃ attenuates IL-6 and IL-1β-mediated inflammatory responses, probably by inhibiting p44/42 MAPK and relA phosphorylation in MacCM-stimulated human white preadipocytes.

An integrated adipose-tissue-on-chip nanoplasmonic biosensing platform for investigating obesity-associated inflammation

Although many advanced biosensing techniques have been proposed for cytokine profiling, there are no clinically available methods that integrate high-resolution immune cell monitoring and in situ multiplexed cytokine detection together in a biomimetic tissue microenvironment. The primary challenge arises due to the lack of suitable label-free sensing techniques and difficulty for sensor integration. In this work, we demonstrated a novel integration of a localized-surface plasmon resonance (LSPR)-based biosensor with a biomimetic microfluidic 'adipose-tissue-on-chip' platform for an in situ label-free, high-throughput and multiplexed cytokine secretion analysis of obese adipose tissue. Using our established adipose-tissue-on-chip platform, we were able to monitor the adipose tissue initiation, differentiation, and maturation and simulate the hallmark formation of crown-like structures (CLSs) during pro-inflammatory stimulation. With integrated antibody-conjugated LSPR barcode sensor arrays, our platform enables simultaneous multiplexed measurements of pro-inflammatory (IL-6 and TNF-α) and anti-inflammatory (IL-10 and IL-4) cytokines secreted by the adipocytes and macrophages. As a result, our adipose-tissue-on-chip platform is capable of identifying stage-specific cytokine secretion profiles from a complex milieu during obesity progression, highlighting its potential as a high-throughput preclinical readout for personalized obesity treatment strategies.

Wild pistachio (Pistacia atlantica mutica) oil improve metabolic syndrome features in rats with high fructose ingestion

OBJECTIVES

Metabolic syndrome is a multiplex risk factor for diabetes and cardiovascular disease. Since some dietary fats such as mono-unsaturated fatty acids (MUFA) modify metabolic syndrome components the aim of the present study was to evaluate the preventive effects of mixture, kernel and hull oils of wild pistachio (WP) (Pistacia atlantica mutica) as good sources of MUFA on different features of this abnormality in rats under induction.

MATERIALS AND METHODS

In this study rats were randomly assigned to six groups with 12 animals per group. Metabolic syndrome was induced by fructose solution in groups 2, 3, 4, 5, and 6. Group 3 received sunflower oil and groups 4, 5, and 6 received mixture, hull and kernel oils of WP (2 ml/kg/day), respectively, for 10 weeks. Then, lipid profiles, glycemic indices, oxidative stress and inflammatory parameters were measured using standard laboratory tests.

RESULTS

Different forms of WP oil induced hypotriglyceridemia, but the hypocholesterolemia effect was seen only in the mixed and kernel oil groups. Kernel oil also significantly reduced LDL and HDL cholesterol (P<0.05). In addition, mixed and kernel oils notably decreased glycemic indices (fasting blood glucose and insulin resistance) compared with the fructose group. Serum insulin levels were significantly increased in the kernel oil group (P<0.05). All WP oils also significantly decreased inflammation (IL-6).

CONCLUSION

The results showed that the consumption of WP kernel oil may have beneficial effects on preventing hyperglycemia, hypertriglyceridemia, hypercholesterolemia, inflammation and pancreatic secretory disorders.

Molecular mechanisms of neuroprotective effect of adjuvant therapy with phenytoin in pentylenetetrazole-induced seizures: Impact on Sirt1/NRF2 signaling pathways

Current anticonvulsant therapies are principally aimed at suppressing neuronal hyperexcitability to prevent or control the incidence of seizures. However, the role of oxidative stress processes in seizures led to the proposition that antioxidant compounds may be considered as promising candidates for limiting the progression of epilepsy. Accordingly, the aim of this study is to determine if coenzyme Q10 (CoQ10) and alpha-tocopherol (α-Toc) have a neuroprotective effect in rats against the observed oxidative stress and inflammation during seizures induced by pentylenetetrazole (PTZ) in rats, and to study their interactions with the conventional antiseizure drug phenytoin (PHT), either alone or in combination. Overall, the data revealed that α-Toc and CoQ10 supplementation can ameliorate PTZ-induced seizures and recommended that nuclear factor erythroid 2-related factor 2 (NRF2) and silencing information regulator 1 (Sirt1) signaling pathways may exemplify strategic molecular targets for seizure therapies. The results of the present study provide novel mechanistic insights regarding the protective effects of antioxidants and suggest an efficient therapeutic strategy to attenuate seizures. Additionally, concurrent supplementation of CoQ10 and α-Toc may be more effective than either antioxidant alone in decreasing inflammation and oxidative stress in both cortical and hippocampal tissues. Also, CoQ10 and α-Toc effectively reverse the PHT-mediated alterations in the brain antioxidant status when compared to PHT only.

Adipose tissue inflammation and VDR expression and methylation in colorectal cancer

Background

Lack of vitamin D (VD) has been associated with colorectal cancer (CRC). VD has anti-inflammatory effects and regulates several cellular pathways by means of its receptor, including epigenetic modifications. Adipose tissue dysfunction has been related to low-grade inflammation, which is related to diseases like cancer. The aim of this study was to explore the relationship between serum 25-hydroxyvitamin D (25(OH)D), adipose tissue gene expression of VD receptor (VDR), pro-inflammatory markers, and the epigenetic factor DNA methyltransferase 3a (DNMT3A) as well as VDR promoter methylation in CRC.

Methods

Blood and visceral adipose tissue from 57 CRC and 50 healthy control subjects were collected. CRC subjects had lower serum 25(OH)D levels and higher VDR gene expression, and these were negatively correlated in the CRC group.

Results

Adipose tissue NFκB1, IL6, and IL1B gene expression were higher in the CRC subjects than in the control subjects. 25(OH)D correlated negatively with NFκB1 and CRP. In turn, CRP correlated positively with NFκB1, IL6, IL1B, and VDR gene expression as well as NFκB1 that correlated positively with IL6 and IL1B. DNMT3A mRNA was negatively correlated with serum 25(OH)D and positively correlated with VDR DNA methylation. VDR DNA methylation at position 4 had lower levels in the CRC group. Global NFκB1 methylation at dinucleotide 3 was lower in the CRC group.

Conclusion

Our results suggest that adipose tissue may be a key factor in CRC development. The low 25(OH)D levels and high adipose tissue VDR expression in CRC may, at least in part, mediate this relationship by modifying adipose tissue DNA methylation and promoting inflammation.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0493-0) contains supplementary material, which is available to authorized users.

Association between vitamin deficiency and metabolic disorders related to obesity

Inappropriate food behavior contributes to obesity and leads to vitamin deficiency. This review discusses the nutritional status of water- and fat-soluble vitamins in obese subjects. We verified that most vitamins are deficient in obese individuals, especially the fat-soluble vitamins, folic acid, vitamin B₁₂ and vitamin C. However, some vitamins have been less evaluated in cases of obesity. The adipose tissue is considered a metabolic and endocrine organ, which in excess leads to changes in body homeostasis, as well as vitamin deficiency which can aggravate the pathological state. Therefore, the evaluation of vitamin status is of fundamental importance in obese individuals.

Vitamin D3 supplementation of a high fat high sugar diet ameliorates prediabetic phenotype in female LDLR-/- and LDLR+/+ mice

INTRODUCTION

Fatty liver disease is prevalent in populations with high caloric intake. Nutritherapeutic approaches are being considered, such as supplementary Vitamin D3 , to improve aspects of metabolic syndrome, namely fatty liver disease, hyperlipidemia, and insulin resistance associated with obesity.

METHODS

We analyzed female LDLR-/- and LDLR+/+ mice on a 10-week diabetogenic diet for markers of fatty liver disease, metabolic strain, and inflammation.

RESULTS

The groups on a high fat high sugar diet with supplementary Vitamin D3 , in comparison with the groups on a high fat high sugar diet alone, showed improved transaminase levels, significantly less hypertriglyceridemia and hyperinsulinemia, and histologically, there was less pericentral hepatic steatosis. Levels of non-esterified fatty acids and lipid peroxidation products were significantly lower in the group supplemented with additional Vitamin D3 , as were systemic markers of inflammation (serum endotoxin and IL-6). M2 macrophage phenotype predominated in the group supplemented with additional Vitamin D3 . Beneficial changes were observed as early as five weeks' supplementation with Vitamin D3 and extended to restoration of high fat high sugar diet induced decrease of bone mineral density.

CONCLUSION

In summary, Vitamin D3 was a significantly beneficial dietary additive to blunt a prediabetic phenotype in diet-induced obesity of female LDLR-/- and LDLR+/+ mice.

Vitamin D Insufficiency Exacerbates Adipose Tissue Macrophage Infiltration and Decreases AMPK/SIRT1 Activity in Obese Rats

Obesity is recognized as a state of chronic low-grade systemic inflammation due to adipose tissue macrophage infiltration and production of proinflammatory adipokines. Decreased vitamin D status is associated with obesity. The specific aim of the present study is to investigate the effects of vitamin D on obesity-induced adipose tissue inflammation. Male Sprague-Dawley rats were randomized and fed a normal diet (NOR, 1000 IU vitamin D/kg diet), a 45% high-fat diet (HF, 1000 IU vitamin D/kg diet), or a 45% high-fat diet containing 25 IU vitamin D/kg diet (HF+LVD) for 12 weeks. The vitamin D-insufficient diet (HF+LVD) led to vitamin D inadequacy as determined by serum 25(OH)D level, 68.56 ± 7.97 nmol/L. The HF+LVD group exacerbated HF-increased adipocyte size, adipogenic gene expression of PPARγ, adipose tissue macrophage recruitment, and proinflammatory cytokine IL-6 and TNFα levels in epididymal white adipose tissue. In addition, vitamin D insufficiency significantly decreased mRNA levels of β-oxidation-related genes such as CPT1α, PGC1α, PPARα, VLCAD, LCAD, MCAD, and UCP1. Moreover, significant decrements of SIRT1 and AMPK activity were noted in obese rats fed with a vitamin D-insufficient diet. The observed deleterious effects of vitamin D insufficiency on adipose tissue expansion, immune cell infiltration and inflammatory status suggest vitamin D plays a beneficial role in adipocyte metabolic metabolism and obesity progression. SIRT1 and AMPK activity may play a role in the mechanism of vitamin D action.

Akkermansia muciniphila improves metabolic profiles by reducing inflammation in chow diet-fed mice

Abnormal shifts in the composition of gut microbiota contribute to the pathogenesis of metabolic diseases, including obesity and type 2 diabetes (T2DM). The crosstalk between gut microbes and the host affects the inflammatory status and glucose tolerance of the individuals, but the underlying mechanisms have not been elucidated completely. In this study, we treated the lean chow diet-fed mice with Akkermansia muciniphila, which is thought to be inversely correlated with inflammation status and body weight in rodents and humans, and we found that A. muciniphila supplementation by daily gavage for five weeks significantly alleviated body weight gain and reduced fat mass. Glucose tolerance and insulin sensitivity were also improved by A. muciniphila supplementation compared with the vehicle. Furthermore, A. muciniphila supplementation reduced gene expression related to fatty acid synthesis and transport in liver and muscle; meanwhile, endoplasmic reticulum (ER) stress in liver and muscle was also alleviated by A. muciniphila. More importantly, A. muciniphila supplementation reduced chronic low-grade inflammation, as reflected by decreased plasma levels of lipopolysaccharide (LPS)-binding protein (LBP) and leptin, as well as inactivated LPS/LBP downstream signaling (e.g. decreased phospho-JNK and increased IKBA expression) in liver and muscle. Moreover, metabolomics profiling in plasma also revealed an increase in anti-inflammatory factors such as α-tocopherol, β-sitosterol and a decrease of representative amino acids. In summary, our study demonstrated that A. muciniphila supplementation relieved metabolic inflammation, providing underlying mechanisms for the interaction of A. muciniphila and host health, pointing to possibilities for metabolic benefits using specific probiotics supplementation in metabolic healthy individuals.

Vitamin D levels in children with familial Mediterranean fever

BACKGROUND

This study aimed to determine whether vitamin D deficiency is more common in children with familial Mediterranean fever (FMF) than in healthy individuals.

METHODS

The study group consisted of 100 patients diagnosed with FMF and 50 healthy children. Serum baseline 25-hydroxyvitamin D levels and other related parameters were evaluated.

RESULTS

The mean (standard deviation [SD]) vitamin D levels in patients with FMF and healthy controls were 24.78 (8.35) and 28.70 (11.70) ng/mL, respectively. Patients with FMF had significantly decreased vitamin D levels compared with those in healthy controls (P = 0.039). Vitamin D levels were similar in patients with FMF with different MEFV mutations (P = 0.633). Age was significantly correlated with vitamin D levels (r = -0.235, P = 0.019). In addition, a negative correlation between parathyroid hormone and vitamin D levels was detected (rs = -0.382, P < 0.0001).

CONCLUSION

This study demonstrated that vitamin D levels are lower in children with FMF than in healthy controls. We speculate that vitamin D levels should be carefully examined, and nutritional supplementation may be required in patients with FMF. Further studies with larger patient populations are needed to confirm the frequency of vitamin D deficiency in patients with FMF.

Effect of vitamin E succinate on inflammatory cytokines induced by high-intensity interval training

Aim and Scope:

The anti-inflammatory effect of vitamin E under moderate exercises has been evaluated. However, the effect of vitamin E succinate, which has more potent anti-inflammatory effect than other isomers of vitamin E has not been evaluated. Therefore, the aim of the present study was to evaluate the effects of vitamin E succinate on tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) production induced by high-intensity interval training (HIIT).

Materials and Methods:

In the present study, 24 rats were randomly divided into control (C), supplementation (S), HIIT, and HIIT + supplementation (HIIT+S) groups. HIIT training protocol on a treadmill (at a speed of 40–54 m/min) and vitamin E succinate supplementation (60 mg/kg/day) was conducted for 6 weeks.

Results:

Serum IL-6 in the HIIT group significantly increased compared with the C group (350.42 ± 123.31 pg/mL vs 158.60 ± 41.96 pg/mL; P = 0.002). Also, serum TNF-α concentrations significantly enhanced (718.15 ± 133.42 pg/mL vs 350.87 ± 64.93 pg/mL; P = 0.001) in the HIIT group compared with the C group. Treatment of the training group with vitamin E numerically reduced IL-6 and TNF-α when compared with the HIIT group (217.31 ± 29.21 and 510.23 ± 217.88, respectively, P > 0.05). However, no significant changes were observed in serum TNF-α (P = 0.31) and IL-6 (P = 0.52) concentrations in the HIIT + S group compared with the C group.

Conclusion:

HIIT-induced IL-6 and TNF-α decreased by administration of Vitamin E succinate.

Impact of anti-inflammatory nutrients on obesity-associated metabolic-inflammation from childhood through to adulthood

Obesity-related metabolic conditions such as insulin resistance (IR), type 2 diabetes and CVD share a number of pathological features, one of which is metabolic-inflammation. Metabolic-inflammation results from the infiltration of immune cells into the adipose tissue, driving a pro-inflammatory environment, which can induce IR. Furthermore, resolution of inflammation, an active process wherein the immune system counteracts pro-inflammatory states, may be dysregulated in obesity. Anti-inflammatory nutritional interventions have focused on attenuating this pro-inflammatory environment. Furthermore, with inherent variability among individuals, establishing at-risk populations who respond favourably to nutritional intervention strategies is important. This review will focus on chronic low-grade metabolic-inflammation, resolution of inflammation and the putative role anti-inflammatory nutrients have as a potential therapy. Finally, in the context of personalised nutrition, the approaches used in defining individuals who respond favourably to nutritional interventions will be highlighted. With increasing prevalence of obesity in younger people, age-dependent biological processes, preventative strategies and therapeutic options are important to help protect against development of obesity-associated co-morbidities.

Adiponectin: A biomarker for chronic hepatitis C?

Adiponectin, a hormone primarily synthesized and secreted by adipose tissue, plays a pivotal role in lipid metabolism. Chronic hepatitis C (CHC) infection is characterized by disordered lipid metabolism, which may potentially evolve into steatosis over a period of time. A growing body of evidence appears to link decreased adiponectin plasma levels with severe CHC-related steatosis, which suggests a potential role of this adipokine as a diagnostic and therapeutic target for clinical application. In this review, we have attempted to summarize the current status of adiponectin research in the context of CHC, concentrating predominantly on its roles in CHC, and its potential relevance as a biomarker for CHC.

Vitamin D modulates adipose tissue biology: possible consequences for obesity?

Cross-sectional studies depict an inverse relationship between vitamin D (VD) status reflected by plasma 25-hydroxy-vitamin D and obesity. Furthermore, recent studies in vitro and in animal models tend to demonstrate an impact of VD and VD receptor on adipose tissue and adipocyte biology, pointing to at least a part-causal role of VD insufficiency in obesity and associated physiopathological disorders such as adipose tissue inflammation and subsequent insulin resistance. However, clinical and genetic studies are far less convincing, with highly contrasted results ruling out solid conclusions for the moment. Nevertheless, prospective studies provide interesting data supporting the hypothesis of a preventive role of VD in onset of obesity. The aim of this review is to summarise the available data on relationships between VD, adipose tissue/adipocyte physiology, and obesity in order to reveal the next key points that need to be addressed before we can gain deeper insight into the controversial VD-obesity relationship.

Vitamin D: A new player in non-alcoholic fatty liver disease?

Vitamin D through its active form 1a-25-dihydroxyvtamin D [1,25(OH)₂D] is a secosteroid hormone that plays a key role in mineral metabolism. Recent years have witnessed a significant scientific interest on vitamin D and expanded its actions to include immune modulation, cell differentiation and proliferation and inflammation regulation. As our understanding of the many functions of vitamin D has grown, the presence of vitamin D deficiency has become one of the most prevalent micronutrient deficiencies worldwide. Concomitantly, non-alcoholic fatty liver disease (NAFLD) has become the most common form of chronic liver disease in western countries. NAFLD and vitamin D deficiency often coexist and epidemiologic evidence has shown that both of these conditions share several cardiometabolic risk factors. In this article we provide an overview of the epidemiology and pathophysiology linking NAFLD and vitamin D deficiency, as well as the available evidence on the clinical utility of vitamin D supplementation in NAFLD.

Adiponectin serum level in chronic hepatitis C infection and therapeutic profile

Hepatic steatosis is commonly seen in the patients with chronic hepatitis C virus (HCV) infection. HCV is closely associated with lipid metabolism, and viral steatosis is more common in genotype 3 infection owing to a direct cytopathic effect of HCV core protein. In non-genotype 3 infection, hepatic steatosis is considered largely to be the result of the alterations in host metabolism; metabolic steatosis is primarily linked with HCV genotype 1. Adipose tissue secretes different hormones involved in glucose and lipid metabolisms. It has been demonstrated that adipocytokines are involved in the pathogenesis of non-alcoholic fatty liver disease, as the decreased plasma adiponectin levels, a soluble matrix protein expressed by adipoctyes and hepatocyte, are associated with liver steatosis. Various studies have shown that steatosis is strongly correlated negatively with adiponectin in the patients with HCV infection. The role of adiponectin in hepatitis C virus induced steatosis is still not completely understood, but the relationship between adiponectin low levels and liver steatosis is probably due to the ability of adiponectin to protect hepatocytes from triglyceride accumulation by increasing β-oxidation of free fatty acid and thus decreasing de novo free fatty acid production.

Phenotypic shift of adipocytes by cholecalciferol and 1α,25 dihydroxycholecalciferol in relation to inflammatory status and calcium content

Recent experimental data seem to suggest a relevant role for 1,25[OH]2cholecalciferol (1,25[OH]2D3) in adipocyte physiology and pathophysiology, with some studies showing adipogenic and pro-inflammatory properties, and others lipolytic and anti-inflammatory functions. Moreover, to our knowledge, the role of cholecalciferol (D3) in adipocytes function is still not known. Therefore, the aim of this study was to investigate in vitro the effects of 1,25[OH]2D3, as well as of D3, in 3T3-L1 adipocytes in basal and inflammatory conditions, testing the effects of different calcium concentrations in adipocytes culture medium. In 3T3-L1 adipocytes, CYP27A1 and CYP27B1 mRNA were detected in basal conditions and induced after D3 treatment. Pre-treatment of 3T3-L1 adipocytes not only with 1,25[OH]2D3, but also with D3 before inflammatory stimulation, significantly prevented the increase in gene expression and protein secretion of IL-6 and TNF-α, and significantly increased IL-10 mRNA and protein production compared with adipocytes treated only with lipopolysaccharide (LPS). Biological effects of D3 were still present after inhibition of P450 activity with ketokonazole. LPS determined a decrease in cell area compared with controls, paralleled by a significant increase in optical density (OD) of lipid droplets, whereas 1,25[OH]2D3 and D3 alone significantly increased adipocytes area and decreased OD. Pretreatment with both forms of vitamin D preserved cells from the reduction in their area observed after LPS treatment. LPS decreased more the area of cells grown in a high calcium medium than of adipocytes grown in a low calcium medium. In the presence of a high calcium medium, 1,25(OH)2D3 treatment preserved cell area, maintaining its anti-inflammatory and adipogenic properties. In conclusion our results show that D3, besides 1,25[OH]2D3, presents anti-inflammatory effects on 3T3-L1, as well as that adipocytes have the enzymatic pathways necessary to locally regulate the production of active forms of vitamin D, capable of influencing adipocyte phenotype and function.

Serum amyloid A-related inflammation is lowered by increased fruit and vegetable intake, while high-sensitive C-reactive protein, IL-6 and E-selectin remain unresponsive

The present study assessed whether increased fruit and vegetable (F&V) intake reduced the concentrations of the inflammatory marker serum amyloid A (SAA) in serum, HDL2 and HDL3 and whether the latter reduction influenced any of the functional properties of these HDL subfractions. The present study utilised samples from two previous studies: (1) the FAVRIT (Fruit and Vegetable Randomised Intervention Trial) study – hypertensive subjects (systolic blood pressure (BP) range 140–190 mmHg; diastolic BP range 90–110 mmHg) were randomised to receive a 1-, 3- or 6-portion F&V/d intervention for 8 weeks, and (2) the ADIT (Ageing and Dietary Intervention Trial) study – older subjects (65–85 years) were randomised to receive a 2- or 5-portion F&V/d intervention for 16 weeks. HDL2 and HDL3 were isolated by rapid ultracentrifugation. Measurements included the following: serum high-sensitive C-reactive protein (hsCRP) by an immunoturbidimetric assay; serum IL-6 and E-selectin and serum-, HDL2- and HDL3-SAA by ELISA procedures; serum-, HDL2- and HDL3-cholesterol ester transfer protein (CETP) activity by a fluorometric assay. Although the concentrations of hsCRP, IL-6 and E-selectin were unaffected by increasing F&V intake in both studies (P>0·05 for all comparisons), those of SAA in HDL3 decreased in the FAVRIT cohort (P= 0·049) and those in HDL2 and HDL3 decreased in the ADIT cohort (P= 0·035 and 0·032), which was accompanied by a decrease in the activity of CETP in HDL3 in the FAVRIT cohort (P= 0·010) and in HDL2 in the ADIT cohort (P= 0·030). These results indicate that SAA responds to increased F&V intake, while other inflammatory markers remain unresponsive, and this leads to changes in HDL2 and HDL3, which may influence their antiatherogenic potential. Overall, the present study provides tangible evidence of the effectiveness of increased F&V intake, which may be of use to health policy makers and the general public.

Obesity, adipose tissue function and the role of vitamin D

Introduction

Obesity is not just a cosmetic problem. Pathological accumulation of body fat can cause many health problems: insulin resistance, impaired glucose tolerance, and diabetes mellitus type 2. It may also increase morbidity and mortality. Adipose tissue plays an important role in body homeostasis by producing and secreting several bioactive proteins known as adipokines: adiponectin, leptin, resistin, visfatin, and apelin, which are involved in the regulation of food intake, glucose and lipid metabolism, and insulin action. There can be observed nutritional deficiencies, despite increased food intake, in morbidly obese people. Data concerning concentrations of serum 25(OH)D₃ presented an inverse correlation with obesity parameters like: BMI (body mass index), waist circumference, fat mass or percentage of body fat. Also, higher insulin sensitivity was associated with higher concentrations of vitamin D.

Conclusions

Studies published up to now suggest that vitamin D plays an important role in adipose tissue function and could be involved in the synthesis and modulation of adipokine production. This article is a review of the literature on fatty tissue function and the role of vitamin D in obesity.

Vitamin D and adipose tissue-more than storage

The pandemic increase in obesity is inversely associated with vitamin D levels. While a higher BMI was causally related to lower 25-hydroxyvitamin D (25(OH)D), no evidence was obtained for a BMI lowering effect by higher 25(OH)D. Some of the physiological functions of 1,25(OH)₂D₃ (1,25-dihydroxycholecalciferol or calcitriol) via its receptor within the adipose tissue have been investigated such as its effect on energy balance, adipogenesis, adipokine, and cytokine secretion. Adipose tissue inflammation has been recognized as the key component of metabolic disorders, e.g., in the metabolic syndrome. The adipose organ secretes more than 260 different proteins/peptides. However, the molecular basis of the interactions of 1,25(OH)₂D₃, vitamin D binding proteins (VDBPs) and nuclear vitamin D receptor (VDR) after sequestration in adipose tissue and their regulations are still unclear. 1,25(OH)₂D₃ and its inactive metabolites are known to inhibit the formation of adipocytes in mouse 3T3-L1 cell line. In humans, 1,25(OH)₂D₃ promotes preadipocyte differentiation under cell culture conditions. Further evidence of its important functions is given by VDR knock out (VDR^−/−) and CYP27B1 knock out (CYP27B1 ^−/−) mouse models: Both VDR^−/− and CYP27B1^−/− models are highly resistant to the diet induced weight gain, while the specific overexpression of human VDR in adipose tissue leads to increased adipose tissue mass. The analysis of microarray datasets from human adipocytes treated with macrophage-secreted products up-regulated VDR and CYP27B1 genes indicating the capacity of adipocytes to even produce active 1,25(OH)₂D₃. Experimental studies demonstrate that 1,25(OH)₂D₃ has an active role in adipose tissue by modulating inflammation, adipogenesis and adipocyte secretion. Yet, further in vivo studies are needed to address the effects and the effective dosages of vitamin D in human adipose tissue and its relevance in the associated diseases.

Metabolic profile response to administration of epigallocatechin-3-gallate in high-fat-fed mice

BACKGROUND

Obesity is associated with increased adipose tissue and glucose intolerance. High-fat diets (HFDs) are known to induce obesity and increase proinflammatory adipokines. The consumption of green tea may improve the health of obese individuals because it contains a potent antioxidant that has effects on body weight, energy expenditure and serum cholesterol concentrations.

METHODS

We examined the effects of epigallocatechin-3-gallate (EGCG) (50 mg/kg body weight per day) or saline after 30 or 60 days of treatment. Mice were distributed into four groups: 1) NS: normolipidic diet receiving saline; 2) NE: normolipidic diet receiving EGCG; 3) HFS: high-fat diet receiving saline; 4) HFE: high-fat diet receiving EGCG.

RESULTS

We observed that administration of a HFD plus EGCG treatment for 60 days reduced delta weight, the relative weights of the mesenteric adipose tissue (MES), retroperitonial adipose tissue (RET), epididymal adipose tissue (EPI), the sum of the adipose tissues (SAT), reduced triacylglycerol (TG) and improved both high-density lipoprotein (HDL) cholesterol levels and the adiponectin/STA ratio when compared with HFS.

CONCLUSIONS

Our results suggest that the chronic administration of EGCG (60 days) promoted a significant improvement in glucose tolerance, decreased adipose tissue deposits, weight mass, TG and HDL-C only when associated with high-fat diet treatment.

The role of vitamin D in critical illness

The role of vitamin D in critical illness is under investigation. Recent data indicate declining levels of serum vitamin D in multiple adult populations. Deficiencies have been strongly linked to infectious processes and certain chronic disorders. Vitamin D deficiency that is present at the onset of critical illness may impact the severity of illness and contribute to less-than-optimal outcomes. This article describes the function of vitamin D, the effects that deficiencies have on body systems, and the emerging role of vitamin D deficiency for critically ill patients.