Adipocyte Hypertrophy Research Articles

An abdominal obesity missense variant in the adipocyte thermogenesis gene TBX15 is implicated in adaptation to cold in Finns.

Mechanisms of abdominal obesity GWAS variants have remained largely unknown. To elucidate these mechanisms, we leveraged subcutaneous adipose tissue (SAT) single nucleus RNA-sequencing and genomics data. After discovering that heritability of abdominal obesity is enriched in adipocytes, we focused on a SAT unique adipocyte marker gene, the transcription factor TBX15, and its abdominal obesity-associated deleterious missense variant, rs10494217. The allele frequency of rs10494217 revealed a north-to-south decreasing gradient, with consistent significant FST values observed for 25 different populations when compared to Finns, a population with a history of genetic isolation. Given the role of Tbx15 in mouse thermogenesis, the frequency may have increased as an adaptation to cold in Finns. Our selection analysis provided significant evidence of selection for the abdominal obesity risk allele T of rs10494217 in Finns, with a north-to-south decreasing trend in other populations, and demonstrated that latitude significantly predicts the allele frequency. We also discovered that the risk allele status significantly affects SAT adipocyte expression of multiple adipocyte marker genes in trans in two cohorts. Two of these trans genes have been connected to thermogenesis, supporting the thermogenic effect of the TBX15 missense variant as a possible cause of its selection. Adipose expression of one trans gene, a lncRNA, AC002066.1, was strongly associated withadipocyte size, implicating it in metabolically unhealthy adipocyte hypertrophy. In summary, the abdominal obesity variant rs10494217 was selected in Finns, and individuals with the risk allele have trans effects on adipocyte expression of genes relating to thermogenesis and adipocyte hypertrophy.

Short-Term Zinc Supplementation Stimulates Visceral Adipose Catabolism and Inflammation in Mice.

Zinc (Zn), a fundamental trace element in human biology, exhibits pivotal roles in sustaining vital physiological processes and regulating metabolic homeostasis. Insufficient zinc intake has been linked to deleterious consequences on growth, reproductive functions, metabolic activities, and immune responses in both humans and animals. Oral zinc supplementation is usually performed to meet zinc requirement. Previous studies have shown that long-term supplementation of zinc in mice impaired AKT signaling and induced adipocyte hypertrophy in visceral adipose tissue. The presented study was conducted to investigate the role and mechanism of short-term zinc supplementation on lipids metabolism. Zinc sulfate was supplemented in the drinking water of C57/BL6J male mice at 30 ppm or 90 ppm for one week. Water consumption, food intake, and body weight were analyzed, adipose tissue and serum profile of metabolites were investigated, and the key genes related to lipid metabolism were analyzed. Short-term zinc supplementation decreased visceral adipose tissue weight and adipocyte size compared to the control group, but no difference was observed in food intake, water consumption, and body weight between the two groups. Further studies revealed that short-term zinc supplementation significantly increased the serum insulin level while decreasing the serum NEFA content. In addition, zinc supplementation increased the expression of Atgl and Hsl in the visceral adipose tissue compared with the control mice. Furthermore, the phosphorylation level of HSL and protein level of PPARg in the epididymal adipose tissue increased by zinc supplementation compared with the control mice. In comparison, the protein level of FASN was down-regulated by short-term zinc supplementation in the epididymal adipose tissue, although the expression of lipogenic genes was not changed. The expression of F4/80 and Tnfa were increased in zinc-supplemented adipose tissue as compared with the control group. Our findings suggest that short-term zinc supplementation might reduce fat deposition by enhancing lipolysis in mice. Future studies could focus on the effect of intermittent zinc supplementation on fat reduction in both animal models and humans.

The Potential of Dehydrated Geniotrigona thoracica Stingless Bee Honey against Metabolic Syndrome in Rats Induced by a High-Carbohydrate, High-Fat Diet

Background/Objectives: Metabolic syndrome (MS) is diagnosed when at least three out of five key risk factors are present: obesity, high blood pressure, insulin resistance, high triglycerides (TG) and low high-density lipoprotein (HDL). MS is often associated with chronic low-grade inflammation. Recent studies have shown that raw stingless bee honey (SBH) can alleviate MS risk factors. However, the high moisture content in raw SBH predisposes it to fermentation, which can degrade its quality. Therefore, dehydrating SBH is necessary to prevent the fermentation process. This study aimed to compare the effects of dehydrated (DeGT) and raw (RGT) SBH from Geniotrigona thoracica species on high-carbohydrate, high-fat diet (HCHF)-induced MS in rats. Methods: Twenty-four male Wistar rats were divided into four groups: control (C), HCHF-induced MS without treatment (MS), HCHF-induced MS treated with DeGT (MS+DeGT) and HCHF-induced MS treated with RGT (MS+RGT). Group C received standard rat chow, while the other groups were fed with HCHF diet for 16 weeks. In the final eight weeks, two HCHF-induced groups received their respective SBH treatments. Results: Both DeGT and RGT treatments reduced energy intake, fat mass, high blood pressure, inflammatory (tumour necrosis factor-alpha (TNF-α)) and obesity (the leptin/adiponectin (L/A) ratio, corticosterone, 11 beta-hydroxysteroid dehydrogenase type-1 (11βHSD1)) markers, as well as prevented histomorphometry changes (prevented adipocyte hypertrophy, increased the Bowman’s space area and glomerular atrophy). Additionally, DeGT increased serum HDL levels, while RGT reduced serum TG, leptin and other inflammatory markers (interleukin-6 (IL-6) and interleukin-1 beta (IL-1β)), as well as hepatosteatosis. Conclusions: While DeGT demonstrates potential as a preventive agent for MS, RGT exhibited more pronounced anti-MS effects in this study.

Histologic Characterization of Tumor-Adjacent Mammary Adipose Tissue in Normal-Weight and Overweight/Obese Patients with Triple-Negative Breast Cancer

Background: Obesity is a risk factor of several types of cancer, including breast cancer. In this study, we aimed to histologically characterize the adipose tissue of the tumor microenvironment (TME) of triple-negative breast cancer (TNBC) in overweight/obese versus normal-weight patients. Methods: TNBC tissue sections from normal-weight (BMI<25) and overweight/obese patients (BMI≥25) were stained with antibodies against CD68, CD163, CD31, CD34, and vimentin. At the invasive tumor front, positive cells were counted in tumor adjacent adipose tissue (AT) and within cancer tissue (CT). Further, the size of the tumor-adjacent and distant mammary adipocytes was determined in perilipin stained sections. Expression of ANGPTL4, CD36 and FABP4, proteins involved in fatty acid metabolism, was analyzed in marginal tumor cells using an immune reactive score. Results: Overweight/obese TNBC patients had significantly larger adipocytes, higher numbers of CD163+ macrophages (BMI<25: 2.80 vs. BMI≥25: 10.45; p = 0.011) and lower numbers of CD31+ (BMI<25: 4.20 vs. BMI≥25: 2.40; p = 0.018) and CD34+ (BMI<25: 14.60 vs. BMI≥25: 5.20; p = 0.045) cells as markers of angiogenesis in the AT as well as a higher frequency of cancer-associated-fibroblast-like cells in the AT and CT (BMI<25: 7.60 vs. BMI≥25: 25.39 in total; p = 0.001). Moreover, expression of CD36 (BMI<25: 2.15 vs. BMI≥25: 2.60; p = 0.041) and ANGPTL4 (BMI<25: 6.00 vs. BMI≥25: 9.80; p = 0.026) was elevated in the TNBC cells of overweight/obese patients. Conclusions: Our data suggest BMI-related changes in the TME of overweight/obese TNBC patients, including hypertrophied adipocytes, reduced vascularization, more M2-like macrophages and CAF-like cells, and an increase in the expression of fatty acid metabolizing proteins in marginal tumor cells, all contributing to a more tumor-promoting, immunosuppressive environment.

Effects of the Fungicide Prothioconazole on Lipid Metabolism in Mice: Whitening Alterations of Brown Adipose Tissue.

With considerable concerns about the associations between metabolic disorders and agricultural biocides, there are scattered data suggesting that the triazole fungicide prothioconazole (PTC) at lower doses than the no observed adverse effect level of 5000 μg/kg/d possibly has the potential to disrupt glycolipid metabolism in mammals. Here, we investigated the effects of 50, 500, and 5000 μg/kg/d of PTC on glycolipid metabolism in mice following 8 weeks of administration via drinking water, with specific attention on brown adipose tissue (BAT) and white adipose tissue (WAT) in addition to the liver. We found that along with the increased serum triglyceride level in the 5000 μg/kg/d group, small fatty vacuoles occurred in livers in all treatment groups, indicating lipid accumulation. No change in WAT was observed, but PTC caused BAT whitening, characterized by adipocyte hypertrophy, more unilocular adipocytes with enlarged lipid droplets, reduced UCP1 levels, and down-regulated Doi2 expression, and even the dose of 50 μg/kg/d was effective. Transcriptomic analysis revealed immune inhibition and circadian rhythm disturbance in BAT from the 5000 μg/kg/d group, which are in agreement with BAT whitening and inactivation. On employing the C3H10T1/2 cells in vitro, we found that PTC treatment concentration-dependently promoted lipid accumulation in brown adipocytes, along with altered expression of thermogenesis-related and circadian genes. Taken together, our study shows that low doses of PTC caused BAT whitening, calling for much attention to the new target by pollutants.

Effects of Environmental Noise Stress on Mouse Metabolism

Environmental noise is associated with various health outcomes. However, the mechanisms through which these outcomes influence behavior and metabolism remain unclear. This study investigated how environmental noise affects the liver, adipose tissue, and brain metabolic functions, leading to behavioral and body weight changes. Mice were divided into a noise group exposed to construction noise and an unexposed (control) group. Behavior and body weight changes were monitored over 50 days. Early changes in response to noise exposure were assessed by measuring plasma cortisol and glial fibrillary acidic protein expression in brain tissues on days 1, 15, and 30. Chronic responses, including changes in lipoprotein and fat metabolism and neurotransmitters, were investigated by analyzing serum lipoprotein levels and body fat mass and evaluating liver, fat, and brain tissue after 50 days. The noise group showed higher locomotor activity and reduced anxiety in the open-field and Y-maze tests. Noise exposure caused an initial weight loss; however, chronic noise increased fat mass and induced adipocyte hypertrophy. Our findings underscore the role of environmental noise-induced stress in augmenting locomotor activity and reducing anxiety in mice through neurotransmitter modulation while increasing the risk of obesity by decreasing HDL cholesterol levels and promoting adipocyte hypertrophy.

Impact of the local renin–angiotensin system in perivascular adipose tissue on vascular health and disease

Perivascular adipose tissue (PVAT) is found locally around blood vessels. It has the ability to release vasoactive chemicals, such as factors that relax and contract blood vessels. PVAT is now recognized as an endocrine organ with metabolic activity and as a “protagonist” for maintaining vascular homeostasis. Angiotensin II, a powerful vasoconstrictor of the renin–angiotensin system (RAS) that can increase blood pressure and vascular tone, is produced locally by PVAT. To mitigate the multiple vascular effects of angiotensin II, PVAT also generates molecules such as angiotensin (1–7), adiponectin, and nitric oxide. Reactive oxygen species and proinflammatory cytokines are produced in greater amounts when PVAT-mediated angiotensin II is present, resulting in endothelial dysfunction, inflammation, atherosclerosis, and other vascular disorders. The anticontractile and procontractile nature of PVAT is frequently disrupted in obese individuals, which increases the production of angiotensin II and decreases the production of anti-inflammatory and vasodilatory factors. These changes in turn exacerbate vascular inflammation, hypertension, and atherosclerosis. PVAT, which is crucial for maintaining vascular homeostasis, loses its anticontractile effect in obesity due to adipocyte hypertrophy, inflammation, and oxidative stress, exacerbating endothelial dysfunction. Overactive RAS in PVAT facilitates the migration and proliferation of vascular smooth muscle cells and atherosclerotic plaques, both of which accelerate the development of atherosclerosis. Targeting PVAT and the local RAS can offer therapeutic benefits in treating hypertension, atherosclerosis, and other vascular diseases. This review highlights the scientific underpinnings of the function of PVAT in regulating the autocrine and paracrine activities of vascular RAS constituents.

Evaluation of the Effects of Diet-Induced Obesity in Zebrafish (Danio rerio): A Comparative Study

Objectives: This study aimed to compare diet-induced obesity (DIO) models in zebrafish and investigate the complications and differences between sexes in biochemical and inflammatory parameters. Methods: Adult animals of both sexes were divided into four groups (n = 50) and fed for eight weeks: control group 1: Artemia sp. (15–30 mg/day/fish); control group 2: commercial fish food (3.5% of average weight); obesity group 1: pasteurized egg yolk powder + soybean oil (5% of average weight); obesity group 2: Artemia sp. (60–120 mg/day/fish). Dietary intake, caloric intake and efficiency, body mass index, biochemical, inflammatory, behavioral, histopathological, and stereological parameters, and inflammation-related gene expression were investigated. Results: Obesity group 1 was the most indicated to investigate changes in the anxious behavioral profile (p < 0.05), triglyceride elevation [52.67 (1.2) mg/dL], adipocyte hypertrophy [67.8 (18.1) µm2; p = 0.0004], and intestinal inflammation. Obesity group 2 was interesting to investigate in terms of weight gain [167 mg; p < 0.0001), changes in fasting glucose [48.33 (4.14) mg/dL; p = 0.003), and inflammatory parameters [IL-6: 4.24 (0.18) pg/mL; p = 0.0015]. Conclusions: Furthermore, both DIO models evaluated in the present study were effective in investigating hepatic steatosis. The data also highlighted that sex influences inflammatory changes and fasting blood glucose levels, which were higher in males (p > 0.05). The results show new metabolic routes to be explored in relation to DIO in zebrafish.

Unacylated but not acylated ghelin plasma levels are negatively associated with adipocyte hypertrophy in humans

Unacylated but not acylated ghelin plasma levels are negatively associated with adipocyte hypertrophy in humans

Adipocytes Size of the Epicardial Adipose Tissue in Patients With Coronary Artery Disease and Coronary Atherosclerosis: Relationship With Parameters of Blood Lipid Transport Function, Carbohydrate Metabolism and Inflammatory Markers

Aim. To assess the potential relationship between morphometric characteristics of adipocytes in epicardial and subcutaneous adipose tissue (EAT, SAT) and the lipid transport function of the blood, glucose e metabolism, and inflammatory biomarkers in patients with ischemic heart disease (IHD) after coronary artery bypass grafting.Material and methods. The study included 47 patients (33 men and 14 women) aged 53-72 years with chronic IHD. The study material was EAT and SAT adipocytes obtained from intraoperative explants. The size of EAT and SAT adipocytes and the proportion of EAT and SAT adipocytes with ≥100 μm and ≤50 μm sizes were determined. Carbohydrate metabolism parameters, blood lipid transport function, and inflammatory biomarkers were assessed. Surrogate indices of insulin resistance (IR) were calculated.Results. The mean size of EAT adipocytes, in contrast to SAT adipocytes, correlated (p<0.05) with serum concentrations of tumor necrosis factor alpha (TNF-α) (rs=0.43), triglycerides (TG) (rs=0.36), interleukin (IL)-1β (rs=0.29), basal C-peptide (rs=0.40) and TyG index (rs=0.32). Male gender and blood concentrations of basal C-peptide and TG in combination were identified as statistically significant determinants of an increase in the mean size of EAT adipocytes. The threshold values of TG and non-high-density lipoprotein cholesterol (nHDL-C) associated with an increase in the mean size of EAT adipocytes ≥87.61 μm were 1.4 and 2.63 mM, respectively. Patients with TG concentrations ≥1.4 mM had a greater size and proportion of hypertrophied EAT adipocytes, IR indices, and higher blood concentrations of basal glucose, high-sensitivity C-reactive protein, TNF-α, and IL-1β. TG concentrations of 1.2-1.4 mM, compared with concentrations <1.2 mM, were associated with a greater mean size of EAT adipocytes and higher serum IL-10 concentrations. Patients with non-HDL-C ≥2.63 mM, compared with its lower concentrations, had more pronounced hypertrophy of EAT adipocytes.Conclusion. Disorders in the morphometric characteristics of EAT adipocytes, in contrast to SAT adipocytes, are associated with increased blood concentrations of TG, non-HDL-C, inflammatory markers, and increased IR indices. It was shown for the first time that a combination of three factors, male gender, blood concentrations of basal C-peptide, and TG, independently of other indicators describe the variability of the mean size of EAT adipocytes. Increases in TG from 1.2 to 1.4 mM are associated with a larger size of EAT adipocytes and cytokine imbalance. Our data confirm the validity of identifying optimal blood concentrations of TG and non-HDL-C in patients with IHD and coronary atherosclerosis.

Rosehip Extract Decreases Reactive Oxygen Species Production and Lipid Accumulation in Hypertrophic 3T3-L1 Adipocytes with the Modulation of Inflammatory State.

Rosa canina L. (rosehip) is used worldwide in traditional medicine as a plant with medicinal properties. However, its anti-obesity effects are not fully explained on a transcriptional level. In the present work, the 3T3-L preadipocytes were utilized to explore the impact of R. canina fruit extract (RCE) on the cellular and molecular pathways involved in adipocyte hypertrophy. Obtained results showed the ability of RCE to reduce lipid overloads in hypertrophic adipocytes associated with the down-regulation of mRNA expressions of adipogenic transcription factors such as PPARγ, C/EBPα, and SREBP-1c as well as genes involved in lipid biosyntheses such as FAS, LPL, and aP2. Moreover, obesity-associated oxidative stress (antioxidant enzyme activities and ROS generation) and inflammation were ameliorated in RCE-treated hypertrophic adipocytes. The mRNA and protein levels of adipokines such as leptin, resistin, and adiponectin were restored to more favorable levels. Rosa canina fruit might be a valuable source of phytochemicals in preventing obesity and obesity-related metabolic complications.

Fiery Connections: Macrophage-Mediated Inflammation, the Journey from Obesity to Type 2 Diabetes Mellitus and Diabetic Kidney Disease.

The high prevalence of diabetes mellitus (DM) poses a significant public health challenge, with diabetic kidney disease (DKD) as one of its most serious consequences. It has become increasingly clear that type 2 DM (T2D) and the complications of DKD are not purely metabolic disorders. This review outlines emerging evidence related to the step-by-step contribution of macrophages to the development and progression of DKD in individuals who specifically develop T2D as a result of obesity. The macrophage is a prominent inflammatory cell that contributes to obesity, where adipocyte hypertrophy leads to macrophage recruitment and eventually to the expansion of adipose tissue. The recruited macrophages secrete proinflammatory cytokines, which cause systemic inflammation, glucose dysregulation, and insulin sensitivity, ultimately contributing to the development of T2D. Under such pathological changes, the kidney is susceptible to elevated glucose and thereby activates signaling pathways that ultimately drive monocyte recruitment. In particular, the early recruitment of proinflammatory macrophages in the diabetic kidney produces inflammatory cytokines/chemokines that contribute to inflammation and tissue damage associated with DKD pathology. Macrophage activation and recruitment are crucial inciting factors that also persist as DKD progresses. Thus, targeting macrophage activation and function could be a promising therapeutic approach, potentially offering significant benefits for managing DKD at all stages of progression.

Influence of Type 2 Diabetes and Adipose Tissue Dysfunction on Breast Cancer and Potential Benefits from Nutraceuticals Inducible in Microalgae.

Breast cancer (BC) represents the most prevalent cancer in women at any age after puberty. From a pathogenetic prospective, despite a wide array of risk factors being identified thus far, poor metabolic health is emerging as a putative risk factor for BC. In particular, type 2 diabetes mellitus (T2DM) provides a perfect example bridging the gap between poor metabolic health and BC risk. Indeed, T2DM is preceded by a status of hyperinsulinemia and is characterised by hyperglycaemia, with both factors representing potential contributors to BC onset and progression. Additionally, the aberrant secretome of the dysfunctional, hypertrophic adipocytes, typical of obesity, characterised by pro-inflammatory mediators, is a shared pathogenetic factor between T2DM and BC. In this review, we provide an overview on the effects of hyperglycaemia and hyperinsulinemia, hallmarks of type 2 diabetes mellitus, on breast cancer risk, progression, treatment and prognosis. Furthermore, we dissect the role of the adipose-tissue-secreted adipokines as additional players in the pathogenesis of BC. Finally, we focus on microalgae as a novel superfood and a source of nutraceuticals able to mitigate BC risk by improving metabolic health and targeting cellular pathways, which are disrupted in the context of T2DM and obesity.

Gestational exposure to BPA alters the expression of glucose and lipid metabolic mediators in the placenta: Role in programming offspring for obesity

Bisphenol A (BPA) exposure during pregnancy is known to predispose offspring to obesity in later life. Our previous studies demonstrated obesogenic effects in BPA-exposed offspring, including excess body fat, increased feed efficiency, adipocyte hypertrophy, and altered leptin signaling. However, the role of the placenta in mediating these effects remained unclear. This study investigates the mechanisms by which BPA exposure affects placental glucose and lipid transporters and their impact on offspring adiposity in Wistar rats. Dams were orally gavaged with BPA [0.4 (low dose-LD) and 4.0 (high dose-HD) μg/kg body weight] from gestational day (gD) 4–14. Gestational exposure to LD BPA increased the expression of 11β hydroxysteroid dehydrogenase 1 (11β HSD1) and estrogen receptor alpha (ERα) proteins (p<0.05) in the placenta compared to control and HD BPA. Similar changes were observed in the expression of mTOR signaling mediators, fatty acid transporters, and intracellular fatty acid-binding proteins. There were no changes in the dam's body weight or lipid and glucose profiles. However, there was a dose dependent increase in glucose transporter (GLUT1) expression in the placenta. While LD BPA increased hexokinase 2 expression in the placenta, HD BPA had no effect. Both doses of BPA increased IL6 expression, but only LD BPA exposure increased PPAR-gamma expression. Additionally, BPA exposure induced ADRP expression and localization, suggesting potential lipid overload in the placenta. Furthermore, BPA exposure altered the placental epigenetic profile, with increased expression of DNA methyltransferases (DNMTs). Overall, gestational BPA exposure led to dose-specific alterations in placental glucose and lipid metabolic activities, possibly playing an role in increasing the supply of these macronutrients to the fetus and predisposing the offspring to obesity.

Low-methoxy-pectin and chlorogenic acid synergistically promote lipolysis and β-oxidation by regulating AMPK signaling pathway in obese mice

Chlorogenic acid (CGA) displays various biological activities in preventing high-calorie diet-induced metabolic complications. The absorption efficiency of CGA in the stomach and small intestine is relatively low, with approximately 70 % of CGA being metabolized by colonic microorganisms before it enters the bloodstream. In this study, we successfully developed CGA-LMP (Low-methoxy-pectin) conjugates to improve the absorption rate of CGA. C57BL/6J mice were fed high-fat diets (HFD) supplemented with CGA, LMP, or CGA-LMP conjugates for a duration of eight weeks. The results demonstrated that the CGA, LMP, or CGA-LMP conjugates prevented HFD-induced hyperlipidemia, inflammation, liver steatosis, and adipocyte hypertrophy in obese mice. Notably, the CGA-LMP conjugates demonstrated superior efficacy in alleviating obesity compared to CGA or LMP alone. Further studies revealed that the primary mechanism of weight loss was the activation of the AMPK signaling pathway, which facilitates lipolysis and lipid β-oxidation. These findings highlight that the enhanced the anti-obesity effectiveness of CGA-LMP conjugates, expanding their potential applications in the field of functional nutrition and foods.

Effects of the FHL2 gene on the development of subcutaneous and intramuscular adipocytes in goats

BackgroundAdipose tissue affects not only the meat quality of domestic animals, but also human health. Adipocyte differentiation is regulated by a series of regulatory genes and cyclins. Four and half-LIM protein (FHL2) is positively correlated with the hypertrophy of adipocytes and can cause symptoms such as obesity and diabetes.ResultIn the transcriptome sequencing analysis of intramuscular adipocytes after three days of differentiation, the differentially expressed gene FHL2 was found. To further explore the biological significance of the differentially expressed gene FHL2, which was downregulated in the mature adipocytes. We revealed the function of FHL2 in adipogenesis through the acquisition and loss of function of FHL2. The results showed that the overexpression of FHL2 significantly increased the expression of adipogenic genes (PPARγ, C/EBPβ) and the differentiation of intramuscular and subcutaneous adipocytes. However, silencing FHL2 significantly inhibited adipocyte differentiation. The overexpression of FHL2 increased the number of adipocytes stained with crystal violet and increased the mRNA expression of proliferation marker genes such as CCNE, PCNA, CCND and CDK2. In addition, it significantly increased the rate of EdU positive cells. In terms of apoptosis, overexpression of FHL2 significantly inhibited the expression of P53 and BAX in both intramuscular and subcutaneous adipocytes, which are involved in cell apoptosis. However, overexpression of FHL2 promoted the expression of BCL, but was rescued by the silencing of FHL2.ConclusionsIn summary, FHL2 may be a positive regulator of intramuscular and subcutaneous adipocyte differentiation and proliferation, and acts as a negative regulator of intramuscular and subcutaneous adipocyte apoptosis. These findings provide a theoretical basis for the subsequent elucidation of FHL2 in adipocytes.

An antifibrotic compound that ameliorates hyperglycaemia and fat accumulation in cell and HFD mouse models.

Appropriate management of blood glucose levels and the prevention of complications are important in the treatment of diabetes. We have previously reported on a compound named HPH-15 that is not only antifibrotic but also AMP-activated protein kinase (AMPK)-activating. In this study, we evaluated whether HPH-15 is useful as a therapeutic medication for diabetes. We examined the effects of HPH-15 on AMPK activation, glucose uptake, fat accumulation and lactic acid production in L6-GLUT4, HepG2 and 3T3-L1 cells, as a model of muscle, liver and fat tissue, respectively. Additionally, we investigated the glucose-lowering, fat-accumulation-suppressing, antifibrotic and AMPK-activating effect of HPH-15 in mice fed a high-fat diet (HFD). HPH-15 at a concentration of 10 µmol/l increased AMPK activation, glucose uptake and membrane translocation of GLUT4 in each cell model to the same extent as metformin at 2 mmol/l. The production of lactic acid (which causes lactic acidosis) in HPH-15-treated cells was equal to or less than that observed in metformin-treated cells. In HFD-fed mice, HPH-15 lowered blood glucose from 11.1±0.3 mmol/l to 8.2±0.4 mmol/l (10 mg/kg) and 7.9±0.4 mmol/l (100 mg/kg) and improved insulin resistance. The HPH-15 (10 mg/kg) group showed the same level of AMPK activation as the metformin (300 mg/kg) group in all organs. The HPH-15-treated HFD-fed mice also showed suppression of fat accumulation and fibrosis in the liver and fat tissue; these effects were more significant than those obtained with metformin. Mice treated with high doses of HPH-15 also exhibited a 44% reduction in subcutaneous fat. HPH-15 activated AMPK at lower concentrations than metformin in vitro and in vivo and improved blood glucose levels and insulin resistance in vivo. In addition, HPH-15 was more effective than metformin at ameliorating fatty liver and adipocyte hypertrophy in HFD-fed mice. HPH-15 could be effective in preventing fatty liver, a common complication in diabetic individuals. Additionally, in contrast to metformin, high doses of HPH-15 reduced subcutaneous fat in HFD-fed mice. Presumably, HPH-15 has a stronger inhibitory effect on fat accumulation and fibrosis than metformin, accounting for the reduction of subcutaneous fat. Therefore, HPH-15 is potentially a glucose-lowering medication that can lower blood glucose, inhibit fat accumulation and ameliorate liver fibrosis.

NR2F2 Reactivation in Early-life Adipocyte Stem-like Cells Rescues Adipocyte Mitochondrial Oxidation.

In humans, perinatal exposure to an elevated omega-6 (n6) relative to omega-3 (n3) Fatty Acid (FA) ratio is associated with the likelihood of childhood obesity. In mice, we show perinatal exposure to excessive n6-FA programs neonatal Adipocyte Stem-like cells (ASCs) to differentiate into adipocytes with lower mitochondrial nutrient oxidation and a propensity for nutrient storage. Omega-6 FA exposure reduced fatty acid oxidation (FAO) capacity, coinciding with impaired induction of beige adipocyte regulatory factors PPARγ, PGC1α, PRDM16, and UCP1. ASCs from n6-FA exposed pups formed adipocytes with increased lipogenic genes in vitro, consistent with an in vivo accelerated adipocyte hypertrophy, greater triacylglyceride accumulation, and increased % body fat. Conversely, n6-FA exposed pups had impaired whole animal 13C-palmitate oxidation. The metabolic nuclear receptor, NR2F2, was suppressed in ASCs by excess n6-FA intake preceding adipogenesis. ASC deletion of NR2F2, prior to adipogenesis, mimicked the reduced FAO capacity observed in ASCs from n6-FA exposed pups, suggesting that NR2F2 is required in ASCs for robust beige regulator expression and downstream nutrient oxidation in adipocytes. Transiently re-activating NR2F2 with ligand prior to differentiation in ASCs from n6-FA exposed pups, restored their FAO capacity as adipocytes by increasing the PPARγ-PGC1α axis, mitochondrial FA transporter CPT1A, ATP5 family synthases, and NDUF family Complex I proteins. Our findings suggest that excessive n6-FA exposure early in life dampens an NR2F2-mediated induction of beige adipocyte regulators, resulting in metabolic programming that is shifted towards nutrient storage.

Lespedeza homoloba enhances the immunosuppressive milieu of adipose tissue and suppresses fasting blood glucose.

Immune cells migrate to hypertrophied adipocytes and release proinflammatory cytokines, leading to adipocyte dysfunction and diabetes. Numerous species of Lespedeza, which are members of the plant family Fabaceae and distributed primarily in temperate Asia and North America, exhibit binding to peroxisome proliferator-activated receptor (PPAR) γ, a target nuclear receptor for treating diabetes. Therefore, the present study aimed to determine which species of Lespedeza plants exert an anti-inflammatory effect in adipose tissue and suppression of blood glucose increase through PPARγ ligand and radical scavenging activity. PPARγ binding and DPPH radical scavenging assays of L. homoloba (LH), L. thunbergii (LT), L. maximowiczii (LM) and L. thunbergii (LT) were performed. LH and LT showed significant ligand activity towards PPARγ and notable radical scavenging activity. LH exhibited a stronger DPPH radical scavenging activity than LT and thus was measured adiponectin secretion from 3T3-L1-derived adipocytes and IL-10 secretion from murine splenocytes. LH increased the adiponectin and the IL-10 secretions. In flow cytometric analysis, BALB/c male mice administered LH exhibited an increase in regulatory T cells (Tregs) and cytotoxic T lymphocyte-associated protein (CTLA)-4+ Tregs as well as a decrease in T helper (Th)17, Th17/Treg ratio and CD8+ and CD4+ T cells in subcutaneous adipose tissue. Conversely, in the spleen, LH decreased Tregs and increased Th17 cells, Th17/Treg ratio and CD4+ and CD8+ T cells. These findings indicated that LH activated immunoreaction in the spleen and Treg cells that migrate to subcutaneous adipose tissue may suppress inflammation. In fasting blood glucose and adiponectin assays, LH-exposed mice exhibited suppression of fasting glucose levels. Therefore, LH may prevent type 2 diabetes by suppressing adipose tissue inflammation.

Sustained improvements in brain health and metabolic markers 24 months following bariatric surgery.

Obesity and its metabolic complications are associated with lower grey matter and white matter densities, whereas weight loss after bariatric surgery leads to an increase in both measures. These increases in grey and white matter density are significantly associated with post-operative weight loss and improvement of the metabolic/inflammatory profiles. While our recent studies demonstrated widespread increases in white matter density 4 and 12 months after bariatric surgery, it is not clear if these changes persist over time. The underlying mechanisms also remain unknown. In this regard, numerous studies demonstrate that the enlargement or hypertrophy of mature adipocytes, particularly in the visceral fat compartment, is an important marker of adipose tissue dysfunction and obesity-related cardiometabolic abnormalities. We aimed (i) to assess whether the increases in grey and white matter densities previously observed at 12 months are maintained 24 months after bariatric surgery; (ii) to examine the association between these structural brain changes and adiposity and metabolic markers 24 months after bariatric surgery; and (iii) to examine the association between abdominal adipocyte diameter at the time of surgery and post-surgery grey and white matter densities changes. Thirty-three participants undergoing bariatric surgery were recruited. Grey and white matter densities were assessed from T1-weighted magnetic resonance imaging scans acquired prior to and 4, 12 and 24 months post-surgery using voxel-based morphometry. Omental and subcutaneous adipose tissue samples were collected during the surgical procedure. Omental and subcutaneous adipocyte diameters were measured by microscopy of fixed adipose tissue samples. Linear mixed-effects models were performed controlling for age, sex, surgery type, initial body mass index, and initial diabetic status. The average weight loss at 24 months was 33.6 ± 7.6%. A widespread increase in white matter density was observed 24 months post-surgery mainly in the cerebellum, brainstem and corpus callosum (P < 0.05, false discovery rate) as well as some regions in grey matter density. Greater omental adipocyte diameter at the time of surgery was associated with greater changes in total white matter density at 24 months (P = 0.008). A positive trend was observed between subcutaneous adipocyte diameter at the time of surgery and changes in total white matter density at 24 months (P = 0.05). Our results show prolonged increases in grey and white matter densities up to 24 months post-bariatric surgery. Greater preoperative omental adipocyte diameter is associated with greater increases in white matter density at 24 months, suggesting that individuals with excess visceral adiposity might benefit the most from surgery.