The Anti-Obesogenic Effects of Muscadine Grapes through Ciliary Neurotrophic Factor Receptor (Cntfr) and Histamine Receptor H1 (Hrh1) Genes in 3T3-L1 Differentiated Mouse Cells.

Obesity and type 2 diabetes are prevalent metabolic diseases that have significant links to several chronic diseases, including cancer, diabetes, hypertension, and cardiovascular disease. Muscadine grape extracts have shown the potential to reduce adiposity and improve insulin sensitivity and glucose control. Thus, this study was designed to determine the potential of muscadine grape berries extract (Pineapple and Southern Home) for its antiobesity properties in 3T3-L1 cells as a model for obesity research. The current study's data indicated the total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydraziyl (DPPH) activity were higher in cultivar (CV) Southern Home, meanwhile, elevated the total flavonoid content (TFC) in Pineapple. Both extracts were safe across the tested range (0-5 mg/mL). A noticeable reduction in lipid accumulation was also found in extract-treated cells. In preadipocytes and adipocytes, the tested extracts showed significant alterations in various genes involved in glucose homeostasis and obesity. The most remarkable findings of the current study are the upregulation of two genes, Cntfr (+712.715-fold) and Hrh1 (+270.11-fold) in CV Pineapple extract-treated adipocytes 3T3-L1 and the high fold increase in Ramp3 induced by both Pineapple and Southern Home in pre-adipose cells. Furthermore, the tested extracts showed a potential to alter the mRNA of various genes, including Zfp91, B2m, Nr3c1, Insr, Atrn, Il6ra, Hsp90ab1, Sort1, and Npy1r. In conclusion, the data generated from the current study suggested that the two extracts under investigation are considered potential candidates for controlling insulin levels and managing obesity.

Role of Corn Peptide Powder in Lipopolysaccharide-Induced Inflammatory Responses in 3T3-L1 Adipocytes.

Corn peptide (CP) is a short, naturally occurring, and physiologically active peptide generated from corn-protease-catalyzed hydrolysis. CP plays a role in preventing obesity-related disorders, but its impact on reducing inflammation is unknown. Hence, this study examined the possible protective effects of corn peptide powder (CPP) against the harmful effects of lipopolysaccharide (LPS), with a particular emphasis on reducing oxidative damage and inflammation in adipocytes. Hence, mature 3T3-L1 adipocytes underwent exposure to 10 ng/mL LPS, with or without CPP (10 and 20 µg/mL). LPS stimulation increased reactive oxygen species and superoxide anion generation. However, this effect was reduced in a dose-dependent manner by pretreatment with CPP. CPP treatment elevated the mRNA expressions of the antioxidant enzymes manganese superoxide dismutase (mnSOD) and glutathione peroxidase 1 (Gpx1) while reducing the mRNA expressions of the cytosolic reactive oxygen species indicators p40 and p67 (NADPH oxidase 2). In addition, CPP inhibited the monocyte chemoattractant protein-1, tumor necrosis factor-alpha, Toll-like receptor 4, and nuclear factor kappa B mRNA expressions induced by LPS. These findings demonstrate that CPP may ameliorate adipocyte dysfunction by suppressing oxidative damage and inflammatory responses through a new mechanism known as Toll-like receptor 4/nuclear factor kappa B-mediated signaling.

Red Oranges and Olive Leaf Waste-Derived Bioactive Extracts Promote Adipocyte Functionality In Vitro.

Obesity is increasingly prevalent worldwide and is linked to metabolic diseases, such as insulin resistance (IR) and type 2 diabetes mellitus (T2DM), due to excessive free fatty acids (FFAs). Although lifestyle changes are effective, they often prove to be insufficient as initial treatments for obesity. Additionally, while surgical and pharmacological interventions are available, they are not entirely safe or effective. Recently, interest has grown in utilizing food waste and plant-derived phenolic compounds for their health benefits, presenting a promising avenue for managing obesity and its related disorders. Indeed, many studies have examined the potential inhibitory effects of the natural extract on adipocyte differentiation and lipid accumulation. This study focused on the evaluation of the effects of standardized extracts obtained from red oranges and olive leaf waste on 3T3-L1 murine pre-adipocyte and adipocyte functionality. Red orange extract (ROE) and olive leaf extract (OLE), alone and in combination, were tested to assess their anti-obesity and anti-inflammatory effects, as well as their potential therapeutic benefits. Three in vitro models were established to investigate the effects of the extracts on (I) adipocyte differentiation; (II) mature and hypertrophic adipocytes challenged with palmitic acid (PA) and erastin (ER), respectively; and (III) erastin-induced cytotoxicity on pre-adipocytes.

TNF-α/Stearate Induced H3K9/18 Histone Acetylation Amplifies IL-6 Expression in 3T3-L1 Mouse Adipocytes.

Extensive evidence supports the connection between obesity-induced inflammation and the heightened expression of IL-6 adipose tissues. However, the mechanism underlying the IL-6 exacerbation in the adipose tissue remains unclear. There is general agreement that TNF-α and stearate concentrations are mildly elevated in adipose tissue in the state of obesity. We hypothesize that TNF-α and stearate co-treatment induce the increased expression of IL-6 in mouse adipocytes. We therefore aimed to determine IL-6 gene expression and protein production by TNF-α/stearate treated adipocytes and investigated the mechanism involved. To test our hypothesis, 3T3-L1 mouse preadipocytes were treated with TNF-α, stearate, or TNF-α/stearate. IL-6 gene expression was assessed by quantitative real-time qPCR. IL-6 protein production secreted in the cell culture media was determined by ELISA. Acetylation of histone was analyzed by Western blotting. Il6 region-associated histone H3 lysine 9/18 acetylation (H3K9/18Ac) was determined by ChIP-qPCR. 3T3-L1 mouse preadipocytes were co-challenged with TNF-α and stearate for 24 h, which led to significantly increased IL-6 gene expression (81 ± 2.1 Fold) compared to controls stimulated with either TNF-α (38 ± 0.5 Fold; p = 0.002) or stearate (56 ± 2.0 Fold; p = 0.013). As expected, co-treatment of adipocytes with TNF-α and stearate significantly increased protein production (338 ± 11 pg/mL) compared to controls stimulated with either TNF-α (28 ± 0.60 pg/mL; p = 0.001) or stearate (53 ± 0.20 pg/mL, p = 0.0015). Inhibition of histone acetyltransferases (HATs) with anacardic acid or curcumin significantly reduced the IL-6 gene expression and protein production by adipocytes. Conversely, TSA-induced acetylation substituted the stimulatory effect of TNF-α or stearate in their synergistic interaction for driving IL-6 gene expression and protein production. Mechanistically, TNF-α/stearate co-stimulation increased the promoter-associated histone H3 lysine 9/18 acetylation (H3K9/18Ac), rendering a transcriptionally permissive state that favored IL-6 expression at the transcriptional and translational levels. Our data represent a TNF-α/stearate cooperativity model driving IL-6 expression in 3T3-L1 cells via the H3K9/18Ac-dependent mechanism, with implications for adipose IL-6 exacerbations in obesity.

2α-Substituted Vitamin D Derivatives Effectively Enhance the Osteoblast Differentiation of Dedifferentiated Fat Cells.

The active form of vitamin D3, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], is a principal regulator of calcium homeostasis through activation of the vitamin D receptor (VDR). Previous studies have shown that 2α-(3-hydroxypropyl)-1,25D3 (O1C3) and 2α-(3-hydroxypropoxy)-1,25D3 (O2C3), vitamin D derivatives resistant to inactivation enzymes, can activate VDR, induce leukemic cell differentiation, and increase blood calcium levels in rats more effectively than 1,25(OH)2D3. In this study, to further investigate the usefulness of 2α-substituted vitamin D derivatives, we examined the effects of O2C3, O1C3, and their derivatives on VDR activity in cells and mouse tissues and on osteoblast differentiation of dedifferentiated fat (DFAT) cells, a cell type with potential therapeutic application in regenerative medicine. In cell culture experiments using kidney-derived HEK293 cells, intestinal mucosa-derived CaCO2 cells, and osteoblast-derived MG63 cells, and in mouse experiments, O2C2, O2C3, O1C3, and O1C4 had a weaker effect than or equivalent effect to 1,25(OH)2D3 in VDR transactivation and induction of the VDR target gene CYP24A1, but they enhanced osteoblast differentiation in DFAT cells equally to or more effectively than 1,25(OH)2D3. In long-term treatment with the compound without the medium change (7 days), the derivatives enhanced osteoblast differentiation more effectively than 1,25(OH)2D3. O2C3 and O1C3 were more stable than 1,25(OH)2D3 in DFAT cell culture. These results indicate that 2α-substituted vitamin D derivatives, such as inactivation-resistant O2C3 and O1C3, are more effective than 1,25(OH)2D3 in osteoblast differentiation of DFAT cells, suggesting potential roles in regenerative medicine with DFAT cells and other multipotent cells.

Adipocyte secreted NRG4 ameliorates age-associated metabolic dysfunction.

With the progressive aging of society, there is an increasing prevalence of age-related diseases that pose a threat to the elderly's quality of life. Adipose tissue, a vital energy reservoir with endocrine functions, is one of the most vulnerable tissues in aging, which in turn influences systematic aging process, including metabolic dysfunction. However, the underlying mechanism is still poorly understood. In this study, we found that NRG4, a novel adipokine, is obviously decreased in adipocyte tissues and serums during aging. Moreover, delivered recombinant NRG4 protein (rNRG4) into aged mice can ameliorate age-associated insulin resistance, glucose disorders and other metabolic disfunction. In addition, rNRG4 treatment alleviates age-associated hepatic steatosis and sarcopenia, accompanied with altered gene signatures. Together, these results indicate that NRG4 plays a key role in the aging process and is a therapeutic target for the treatment of age-associated metabolic dysfunction.

Anti-Obesity Activities of the Compounds from Perilla frutescens var. acuta and Chemical Profiling of the Extract.

Perilla frutescens var. acuta (Lamiaceae) is widely used not only as an oil or a spice, but also as a traditional medicine to treat colds, coughs, fever, and indigestion. As an ongoing effort, luteolin-7-O-diglucuronide (1), apigenin-7-O-diglucuronide (2), and rosmarinic acid (3) isolated from P. frutescens var. acuta were investigated for their anti-adipogenic and thermogenic activities in 3T3-L1 cells. Compound 1 exhibited a strong inhibition against adipocyte differentiation by suppressing the expression of Pparg and Cebpa over 52.0% and 45.0%, respectively. Moreover, 2 inhibited the expression of those genes in a dose-dependent manner [Pparg: 41.7% (5 µM), 62.0% (10 µM), and 81.6% (50 µM); Cebpa: 13.8% (5 µM), 18.4% (10 µM), and 37.2% (50 µM)]. On the other hand, the P. frutescens var. acuta water extract showed moderate thermogenic activities. Compounds 1 and 3 also induced thermogenesis in a dose-dependent manner by stimulating the mRNA expressions of Ucp1, Pgc1a, and Prdm16. Moreover, an LC-MS/MS chromatogram of the extract was acquired using UHPLC-MS2 and it was analyzed by feature-based molecular networking (FBMN) and the Progenesis QI software (version 3.0). The chemical profiling of the extract demonstrated that flavonoids and their glycoside derivatives, including those isolated earlier as well as rosmarinic acid, are present in P. frutescens var. acuta.

Effects of glucocorticoids on adipose tissue plasticity.

Glucocorticoids (GCs) play an important role in metabolic adaptation, regulating carbohydrate-lipid homeostasis and the immune system. Because they also have anti-inflammatory and immunosuppressive properties, synthetic analogues of GCs have been developed and are widely used in the treatment of chronic inflammatory conditions and in organ transplantation. GCs are among the most commonly prescribed drugs in the world. However, long term and high GC doses can cause side effects such as GC-induced diabetes and lipodystrophy. In recent years, a large number of independent studies have reported the effects of constitutive and adipocyte-specific deletion of the GC receptor (GR) in mice under different diets and treatments, resulting in contrasting phenotypes. To avoid potential compensatory mechanisms associated with the constitutive adipocyte GR silencing during adipose tissue development, our team has generated an inducible mouse model of GR deletion specifically in the adipocyte (AdipoGR-KO). Using this mouse model, we were able to demonstrate the critical role of the adipocyte GR in GC-induced metabolic changes. Indeed, under conditions of hypercorticism, AdipoGR-KO mice showed an improvement in glucose tolerance and insulin sensitivity, as well as in lipid profile, despite a massive increase in adiposity. This result is explained by a densification of adipose tissue vascularization, highlighting the repressive role of adipocyte GR in the healthy expansion of this tissue. Our work has largely contributed to the demonstration of the important role of the adipocyte GR in the physiology and pathophysiology of the adipose tissue and its impact on energy homeostasis.

Assessment of the disruption effects of tetrabromobisphenol A and its analogues on lipid metabolism using multiple in vitro models.

Tetrabromobisphenol A (TBBPA), a widely-used brominated flame retardant, has been revealed to exert endocrine disrupting effects and induce adipogenesis. Given the high structural similarities of TBBPA analogues and their increasing exposure risks, their effects on lipid metabolism are necessary to be explored. Herein, 9 representative TBBPA analogues were screened for their interference on 3T3-L1 preadipocyte adipogenesis, differentiation of C3H10T1/2 mesenchymal stem cells (MSCs) to brown adipocytes, and lipid accumulation of HepG2 cells. TBBPA bis(2-hydroxyethyl ether) (TBBPA-BHEE), TBBPA mono(2-hydroxyethyl ether) (TBBPA-MHEE), TBBPA bis(glycidyl ether) (TBBPA-BGE), and TBBPA mono(glycidyl ether) (TBBPA-MGE) were found to induce adipogenesis in 3T3-L1 preadipocytes to different extends, as evidenced by the upregulated intracellular lipid generation and expressions of adipogenesis-related biomarkers. TBBPA-BHEE exhibited a stronger obesogenic effect than did TBBPA. In contrast, the test chemicals had a weak impact on the differentiation process of C3H10T1/2 MSCs to brown adipocytes. As for hepatic lipid formation test, only TBBPA mono(allyl ether) (TBBPA-MAE) was found to significantly promote triglyceride (TG) accumulation in HepG2 cells, and the effective exposure concentration of the chemical under oleic acid (OA) co-exposure was lower than that without OA co-exposure. Collectively, TBBPA analogues may perturb lipid metabolism in multiple tissues, which varies with the test tissues. The findings highlight the potential health risks of this kind of emerging chemicals in inducing obesity, non-alcoholic fatty liver disease (NAFLD) and other lipid metabolism disorders, especially under the conditions in conjunction with high-fat diets.

Myo-inositol rescued insulin resistance and dyslipidemia in db/db mice.

Myo-inositol (MI), present in a variety of foods, is essential in several important processes of cell physiology. In this study, we explored the protective effects of MI against hyperglycemia and dyslipidemia in db/db mice, a typical animal model of type 2 diabetes mellitus (T2DM). MI supplement effectively suppressed the high plasma glucose and insulin levels and markedly relieved the insulin resistance (IR) in the db/db mice, comparable to metformin's effects. In MIN6 pancreatic ß cells, MI also restrained the upsurge of insulin secretion stimulated by high-concentration glucose but had no impact on the promoted cell proliferation. Moreover, MI abated the enhanced plasma triglyceride and total cholesterol levels in the db/db mice. Notably, the lipid droplet formation of mesenchymal stem cells (MSCs) from db/db mice was significantly diminished after the treatment of MI, indicating that MI could effectively inhibit the differentiation of db/db mouse MSCs into adipocytes. However, MI regretfully failed to control obesity in db/db mice. This work proved that MI significantly helped db/db mice's metabolic disorders, indicating that MI has potential as an effective adjunctive treatment for hyperglycemia and dyslipidemia in T2DM patients.

7-MEGA™ inhibits adipogenesis in 3T3-L1 adipocytes and suppresses obesity in high-fat-diet-induced obese C57BL/6 mice.

BACKGROUND: Overweight, often known as obesity, is the abnormal and excessive accumulation of fat that exposes the health of a person at risk by increasing the likelihood that they may experience many chronic conditions. Consequently, obesity has become a global health threat, presenting serious health issues, and attracting a lot of attention in the healthcare profession and the scientific community. METHOD: This study aims to explore the anti-adipogenic properties of 7-MEGA™ in an attempt to address obesity, using both in vitro and in vivo research. The effects of 7MEGA™ at three distinct concentrations were investigated in obese mice who were given a high-fat diet (HFD) and 3T3-L1 adipocytes. RESULTS: 7MEGA™ decreased the total fat mass, overall body weight, and the perirenal and subcutaneous white adipose tissue (PWAT and SWAT) contents in HFD mice. Additionally, 7MEGA™ showed promise in improving the metabolic health of individuals with obesity and regulate the levels of insulin hormone, pro-inflammatory cytokines and adipokines. Furthermore, Peroxisome proliferator-activated receptors (PPAR) α and γ, Uncoupling Protein 1 (UCP-1), Sterol Regulatory Element-Binding Protein 1 (SREBP-1), Fatty Acid-Binding Protein 4 (FABP4), Fatty Acid Synthase (FAS), Acetyl-CoA Carboxylase (ACC), Stearoyl-CoA Desaturase-1 (SCD-1) and CCAAT/Enhancer-Binding Protein (C/EBPα) were among the adipogenic regulators that 7MEGA™ could regulate. CONCLUSION: In summary, this study uncovered that 7MEGA™ demonstrates anti-adipogenic and anti-obesity effects, suggesting its potential in combating obesity.

Inhibition and reversal of a TGF-ß1 induced myofibroblast phenotype by adipose tissue-derived paracrine factors.

BACKGROUND: Hypertrophic scarring results from myofibroblast differentiation and persistence during wound healing. Currently no effective treatment for hypertrophic scarring exists however, autologous fat grafting has been shown to improve scar elasticity, appearance, and function. The aim of this study was to understand how paracrine factors from adipose tissues and adipose-derived stromal cells (ADSC) affect fibroblast to myofibroblast differentiation. METHODS: The transforming growth factor-ß1 (TGF-ß1) induced model of myofibroblast differentiation was used to test the effect of conditioned media from adipose tissue, ADSC or lipid on the proportion of fibroblasts and myofibroblasts. RESULTS: Adipose tissue conditioned media inhibited the differentiation of fibroblasts to myofibroblasts but this inhibition was not observed following treatment with ADSC or lipid conditioned media. Hepatocyte growth factor (HGF) was readily detected in the conditioned medium from adipose tissue but not ADSC. Cells treated with HGF, or fortinib to block HGF, demonstrated that HGF was not responsible for the inhibition of myofibroblast differentiation. Conditioned media from adipose tissue was shown to reduce the proportion of myofibroblasts when added to fibroblasts previously treated with TGF-ß1, however, conditioned media treatment was unable to significantly reduce the proportion of myofibroblasts in cell populations isolated from scar tissue. CONCLUSIONS: Cultured ADSC or adipocytes have been the focus of most studies, however, this work highlights the importance of considering whole adipose tissue to further our understanding of fat grafting. This study supports the use of autologous fat grafts for scar treatment and highlights the need for further investigation to determine the mechanism.

Development of piperine nanoparticles stabilized by OSA modified starch through wet-media milling technique with enhanced anti-adipogenic effect in 3T3-L1 adipocytes.

Piperine (PIP) has been known for its pharmacological activities with low water solubility and poor dissolution, which limits its nutritional application. The purpose of this research was to enhance PIP stability, dispersibility and biological activity by preparing PIP nanoparticles using the wet-media milling approach combined with nanosuspension solidification methods of spray/freeze drying. Octenyl succinic anhydride (OSA)-modified waxy maize starch was applied as the stabilizer to suppress aggregation of PIP nanoparticles. The particle size, redispersibility, storage stability and in vitro release behavior of PIP nanoparticles were measured. The regulating effect on adipocyte differentiation was evaluated using 3T3-L1 cell model. Results showed that PIP nanoparticles had a reduced particle size of 60 ± 1 nm, increased release rate in the simulated gastric (SGF) and intestinal fluids (SIF) and enhanced inhibition effect on adipogenesis in 3T3-L1 cells compared with free PIP, indicating that PIP-loaded nanoparticles with improved stability and anti-adipogenic property were developed successfully by combining wet-media milling and drying methods.

Evaluating the Nutritional Composition of Unripe Citrus and Its Effect on Inhibiting Adipogenesis and Adipocyte Differentiation.

Citrus fruits offer a range of health benefits due to their rich nutritional profile, including vitamin C, flavonoids, carotenoids, and fiber. It is known that unripe citrus has higher levels of vitamin C, dietary fiber, polyphenols, and flavonoids compared to mature fruits. In this study, we assessed the nutritional components of unripe citrus peel and pressed juices, as well as their anti-obesity potential through the modulation of adipocyte differentiation and the expression of adipogenesis-related genes, specifically PPARγ and C/EBPα, in 3T3-L1 preadipocytes. Our analysis revealed that unripe citrus peel exhibited elevated levels of fiber and protein compared to pressed juice, with markedly low levels of free sugar, particularly sucrose. The content of hesperidin, a representative flavonoid in citrus fruits, was 3,157.6 mg/kg in unripe citrus peel and 455.5 mg/kg in pressed juice, indicating that it was approximately seven times higher in unripe citrus peel compared to pressed juice. Moreover, we observed that the peel had a dose-dependently inhibitory effect on adipocyte differentiation, which was linked to a significant downregulation of adipogenesis-related gene expression. Thus, our findings suggest that unripe citrus possesses anti-obesity effects by impeding adipogenesis and adipocyte differentiation, with the peel demonstrating a more pronounced effect compared to pressed juice.

Imeglimin modulates mitochondria biology and facilitates mitokine secretion in 3T3-L1 adipocytes.

AIMS: Imeglimin, a novel antidiabetic drug, has recently been reported to affect pancreatic ß-cells and hepatocytes. Adipose tissue plays a crucial role in systemic metabolism. However, its effect on adipocytes remains unexplored. Herein, we investigated the effects of imeglimin on adipocytes, particularly in the mitochondria. MAIN METHODS: The 3T3-L1 adipocytes were treated with imeglimin. Mitochondrial respiratory complex I activity and NAD+, NADH, and AMP levels were measured. Protein expression levels were determined by western blotting, mitochondrial DNA and mRNA expression levels were determined using quantitative polymerase chain reaction, and secreted adipocytokine and mitokine levels were determined using adipokine array and enzyme-linked immunosorbent assay. KEY FINDINGS: Imeglimin inhibited complex I activity, decreased the NAD+/NADH ratio, and increased AMP levels, which were associated with the enhanced phosphorylation of AMP-activated protein kinase. In addition, imeglimin increased the mitochondrial DNA content and levels of mitochondrial transcription factor A and peroxisome proliferator-activated receptor-γ coactivator 1-α mRNA, which were abolished by Ly294002, a phosphoinositide 3-kinase inhibitor. Furthermore, imeglimin facilitated the expression levels of markers of the mitochondrial unfolded protein response, and the gene expression and secretion of two mitokines, fibroblast growth factor 21 and growth differentiation factor 15. The production of both mitokines was transcriptionally regulated and abolished by phosphoinositide 3-kinase and Akt inhibitors. SIGNIFICANCE: Imeglimin modulates mitochondrial biology in adipocytes and may exert a mitohormetic effect through mitokine secretion.

Preadipocytes potentiate melanoma progression and M2 macrophage polarization in the tumor microenvironment.

Melanoma, the deadliest skin cancer, originates from epidermal melanocytes. The influence of preadipocytes on melanoma is less understood. We co-cultured mouse melanoma B16 cells with 3T3L1 preadipocytes to form mixed spheroids and observed increased melanoma proliferation and growth compared to B16-only spheroids. Metastasis-related proteins YAP, TAZ, and PD-L1 levels were also higher in mixed spheroids. Treatment with exosome inhibitor GW4869 halted melanoma growth and reduced expression of these proteins, suggesting exosomal crosstalk between B16 and 3T3L1 cells. MiR-155 expression was significantly higher in mixed spheroids, and GW4869 reduced its levels. Additionally, co-culturing with Raw264.7 macrophage cells increased M2 markers IL-4 and CD206 in Raw264.7 cells, effects that were diminished by GW4869. These results indicate that preadipocytes may enhance melanoma progression and metastasis via exosomal interactions.

EGCG alleviates heat-stress-induced fat deposition by targeting HSP70 through activation of AMPK-SIRT1-PGC-1α in porcine subcutaneous preadipocytes.

Obesity has emerged as a prominent global health concern, with heat stress posing a significant challenge to both human health and animal well-being. Despite a growing interest in environmental determinants of obesity, very few studies have examined the associations between heat stress-related environmental factors and adiposity. Consequently, there exists a clear need to understand the molecular mechanisms underlying the obesogenic effects of heat stress and to formulate preventive strategies. This study focused on culturing porcine subcutaneous preadipocytes at 41.5 ℃ to induce heat stress, revealing that this stressor triggered apoptosis and fat deposition. Analysis demonstrated an upregulation in the expression of HSP70, BAX, adipogenesis-related genes (PPARγ, AP2, CEBPα and FAS), the p-AMPK/AMPK ratio and SIRT1, PGC-1α in the heat stress group compared to the control group (P < 0.05). Conversely, the expression of lipid lysis-related genes (ATGL, HSL and LPL) and Bcl-2 decreased in the heat stress group compared to the control group (P < 0.05). Furthermore, subsequent activator and/or inhibitor experiments validated that heat stress modulated HSP70 and AMPK signalling pathways to enhance lipogenesis and inhibit lipolysis in porcine subcutaneous preadipocytes. Importantly, this study reveals, for the first time, that EGCG mitigates heat-stress-induced fat deposition by targeting HSP70 through the activation of AMPK-SIRT1-PGC-1α in porcine subcutaneous preadipocytes. These findings elucidate the molecular mechanisms contributing to heat stress-induced obesity and provide a foundation for the potential clinical utilisation of EGCG as a preventive measure against both heat stress and obesity.

miR-486-5p-rich extracellular vesicles derived from patients with olanzapine-induced insulin resistance negatively affect glucose-regulating function.

A high risk of glucometabolic disorder severely disturbs compliance and limits the clinical application of olanzapine. MicroRNAs (miRNAs) in extracellular vesicles (EVs) have been reported as emerging biomarkers in glucolipid metabolic disorders. A total of 81 individuals with continuous olanzapine treatment over 3 months were recruited in this study, and plasma EVs from these individuals were isolated and injected into rats via the tail vein to investigate the glucose-regulating function in vivo. Moreover, we performed a miRNA profiling assay by high through-put sequencing to clarify the differentiated miRNA profiles between two groups of patients who were either susceptible or not susceptible to olanzapine-induced insulin resistance (IR). Finally, we administered antagomir and cocultured them with adipocytes to explore the mechanism in vitro. The results showed that individual insulin sensitivity varied in those patients and in olanzapine-administered rats. Furthermore, treatment with circulating EVs from patients with olanzapine-induced IR led to the development of metabolic abnormalities in rats and adipocytes in vitro through the AKT-GLUT4 pathway. Deep sequencing illustrated that the miRNAs of plasma EVs from patients showed a clear difference based on susceptibility to olanzapine-induced IR, and miR-486-5p was identified as a notable gene. The adipocyte data indicated that miR-486-5p silencing partially reversed the impaired cellular insulin sensitivity. Collectively, this study confirmed the function of plasma EVs in the interindividual differences in olanzapine-induced insulin sensitivity.

Berberine attenuates obesity-induced insulin resistance by inhibiting miR-27a secretion.

INTRODUCTION: Berberine (BBR) is an alkaloid found in plants. It has neuroprotective, anti-inflammatory and lipid-lowering activity. However, the efficacy of treatment with BBR and the mechanisms through which it acts need further study. AIMS: This study investigated the therapeutic effects and the mechanism of action of BBR on obesity-induced insulin resistance in peripheral tissues. METHODS: High-fat-fed C57BL/6J mice and low-fat-fed C57BL/6J mice with miR-27a overexpression were given BBR intervention (100 mg/kg, po), and the oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were performed. Palmitic acid-stimulated hypertrophic adipocyte models were treated with BBR (10 µM). Related indicators and protein expression levels were examined. RESULTS: The AUCs of the OGTT and the ITT in the BBR intervention group were reduced significantly (p < 0.01) (p < 0.05), and the serum biochemical parameters, including FBG, TC, TG and LDL-C were significantly reduced after BBR intervention. In the in vitro experiments, the triglyceride level and volume of lipid droplets decreased significantly after BBR intervention (p < 0.01) (p < 0.05). Likewise, BBR ameliorates skeletal muscle and pancreas insulin signalling pathways in vivo and in vitro. DISCUSSION: The results showed that BBR significantly ameliorated insulin resistance, reduced body weight and percent body fat and improved serum biochemical parameters in mice. Likewise, BBR reduced triglyceride level and lipid droplet volume in hypertrophic adipocytes, BBR improved obesity effectively. Meanwhile, BBR ameliorated the histomorphology of the pancreas, and skeletal muscle and pancreas insulin related signalling pathways of islets in in vitro and in vivo experiments. The results further demonstrated that BBR inhibited miR-27a levels in serum from obese mice and supernatant of hypertrophic adipocytes. miR-27a overexpression in low-fat fed mice indicated that miR-27a caused insulin resistance, and BBR intervention significantly improved the miR-27a induced insulin resistance status. CONCLUSION: This study demonstrates the important role of BBR in obesity-induced peripheral insulin resistance and suggest that the mechanism of its effect may be inhibition of miR-27a secretion.

Hypocholesterolemic potential of Bacillus amyloliquefaciens KAVK1 modulates lipid accumulation on 3T3-L1 adipose cells and high fat diet-induced obese rat model.

The significance of microorganisms occurring in foods is predominantly targeted due to their application for identifying a novel range of the bacterial spectrum. Diverse microbial species are capable of exhibiting potential pharmacological activities like antimicrobial and anticancer. Microbial strains capable of reducing obesity-related syndromes have also been reported. In the present study, the hypocholesterolemic efficacy of Bacillus amyloliquefaciens isolated from dairy products was scrutinised by in vitro (3T3-L1 adipose cells) and in vivo (high-fat diet-induced obese Wistar albino rats) methods. Potential cholesterol-lowering isolates were screened using a plate assay method and optimised by physical parameters. Molecular identification of the topmost five cholesterol-lowering isolates was acquired by amplification of the 16 S rRNA gene region. Bacillus amyloliquefaciens strain KAVK1, followed by strains KAVK2, KAVK3, KAVK4, and KAVK5 were molecularly determined. Further, cholesterol-lowering strains degraded the spectral patterns determined by the side chain of a cholesterol molecule. The anti-lipase activity was demonstrated using the porcine pancreatic lipase inhibitory method and compared with the reference compound Atorvastatin. Lyophilised strain KAVK1 revealed maximum pancreatic lipase inhibition. Strain KAVK1 attenuated lipid accumulation in 3T3-L1 adipose cell line predicted by Oil Red O staining method. Significant reduction of body weight and change in lipid profile was recognised after the supplement of KAVK1 to obese rats. Histopathological changes in organs were predominantly marked. The result of this study implies that the cholesterol-lowering B. amyloliquefaciens KAVK1 strain was used to treat hypercholesterolemia.