Anti-adipogenic Effects Research Articles

Bifidobacterium longum subsp. infantis YB0411 Inhibits Adipogenesis in 3T3-L1 Pre-adipocytes and Reduces High-Fat-Diet-Induced Obesity in Mice.

Although the health benefits of probiotics have been widely known for decades, there has still been limited use of probiotic bacteria in anti-obesity therapy. Herein, we demonstrated the role of Bifidobacterium longum subsp. infantis YB0411 (YB, which was selected by an in vitro adipogenesis assay) in adipogenic differentiation in 3T3-L1 pre-adipocytes. We observed that YB-treatment effectively reduced triglyceride accumulation and the expression of CCAAT/enhancer-binding protein α, β, and δ (C/EBPα, C/EBPβ, and C/EBPδ), peroxisome proliferator-activated receptor γ (PPARγ), fatty acid-binding protein 4 (aP2), and acetyl-CoA carboxylase (ACC). YB-treatment also reduced the levels of core autophagic markers (p62 and LC3B) in 3T3-L1 pre-adipocytes. Small-interfering-RNA-mediated knockdown and competitive-chemical-inhibition assays showed that AMP-activated protein kinase (AMPK) commenced the anti-adipogenic effect of YB. In addition, YB supplement markedly reduced body weight and fat accretion in mice with high-fat-diet-induced obesity. Our findings suggest that YB may be used as a potential probiotic candidate to ameliorate obesity.

Anti‐adipogenic Effects of αAL14 Mediated by Modulation of PI3K/Akt Pathways in 3T3-L1 Cells

A model peptide, αAL14, was designed from the primary structure of a novel antimicrobial peptide purified form the abalone. αAL14 was only reported for antimicrobial and anti-angiogenic effects. Therefore, in this study, we investigated anti-adipogenic effects of αAL14 on preadipocyte, 3T3-L1. Obesity is an imbalance in metabolism caused by excessive energy intake or reduced energy consumption, and fat accumulates in the body, which causes chronic disease such as high pressure, cardiovascular disease, diabetes, and cancer. Inhibition of adipogenesis has been focused on as a strategy for treating metabolic disease including diabetes and obesity. In order to confirm the effect on adipocyte differentiation, αAL14 was treated while inducing differentiation from preadipocytes into mature adipocytes. We observed that αAL14 potently and dose-dependently suppressed accumulation of lipid droplets during mature adipocyte differentiation. αAL14 also down-regulated the expression of key adipogenic regulator such as peroxisome proliferator-activated receptor γ (PPAR γ), CCAAT/enhancer binding protein α (C/EBP α) and sterol regulatory element-binding protein 1 (SREBP1). In addition, αAL14 diminished the insulin-stimulated phosphoinositide 3-kinase (PI3K)/Akt signaling and its downstream factors that promote adipogenesis by inducing the expression of PPAR γ, such as mechanistic target of rapamycin (mTOR), glycogen synthase kinase 3β (GSK-3β) and forkhead box (Fox) transcription factors, which may reduce glucose uptake in response to insulin and lipid accumulation. These results indicated that αAL14 suppresses adipocyte differentiation and lipid accumulation depending on multiple mechanisms. In summary, αAL14 could be a novel inhibitor of adipogenesis and may have applications for the treatment of obesity.

Oxidant therapy improves adipogenic differentiation of adipose-derived stem cells in human wound healing

BackgroundAdipose-derived stem cells (ASC) and adipocytes are involved in numerous physiological and pathophysiological conditions, which have been extensively described in subcutaneous and visceral fat depots over the past two decades. However, much less is known about ASC and adipocytes outside classical fat tissue depots and their necessity in tissue remodeling after injury. Therefore, we investigated the etiology of adipocytes in human granulation tissue and define their possible role wound healing.MethodsIdentification of human wound tissue adipocytes was determined by immunohistochemical staining of granulation tissue sections from patients undergoing surgical debridement. Stromal cell fractions from granulation tissue and subcutaneous fat tissue were generated by collagenase type II-based protocols. Pro- and anti-inflammatory wound bed conditions were mimicked by THP1- and CD14+ monocyte-derived macrophage models in vitro. Effects of macrophage secretome on ASC differentiation and metabolism were determined by immunoblotting, flow cytometry, and microscopy assessing early and late adipocyte differentiation states. Functional rescuing experiments were conducted by lentiviral transduction of wildtype PPARG, IL1RA, and N-chlorotaurine (NCT) treatment.ResultsSingle and clustered adipocyte populations were detected in 11 out of 13 granulation tissue specimens and single-cell suspensions from granulation tissue showed adipogenic differentiation potential. Pro-inflammatory signaling by IFNG/LPS-stimulated macrophages (M (IFNG/LPS)) inhibited the maturation of lipid droplets in differentiated ASC. In contrast, anti-inflammatory IL4/IL13-activated macrophages (M (IL4/IL13)) revealed minor effects on adipocyte development. The M (IFNG/LPS)-induced phenotype was associated with a switch from endogenous fatty acid synthesis to glycolysis-dominated cell metabolism and increased pro-inflammatory cytokine production. Impaired adipogenesis was associated with increased, but seemingly non-functional, CEBPB levels, which failed to induce downstream PPARG and CEBPA. Neither transgenic PPARG overexpression, nor inhibition of IL1B was sufficient to rescue the anti-adipogenic effects induced by IFNG/LPS-activated macrophages. Instead, macrophage co-treatment during stimulation with NCT, a mild oxidant produced by activated granulocytes present in human wounds in vivo, significantly attenuated the anti-adipogenic effects.ConclusionsIn conclusion, the appearance of adipocytes in wound tissue indicates a prevailing anti-inflammatory environment that could be promoted by NCT treatment and may be associated with improved healing outcomes.Graphical abstract

Functional triterpenoids from medicinal fungi Ganoderma applanatum: A continuous search for antiadipogenic agents

Previously, we have demonstrated the antiadipogenic benefits of Ganoderma triterpenoids (GTs), which indicated GTs have potential therapeutic implications for obesity. In this study, the EtOAc extract of Ganoderma applanatum was further phytochemically investigated for searching new antiadipogenic agents, which led to the isolation of a total of 15 highly oxygenated lanostane triterpenoids, including 9 new compounds (1–9) and 6 known analogues (10–15). Structurally, ganodapplanoic acids A and B (1, 2) are two rearranged 6/6/5/6-fused lanostane-type triterpenoids with an unusual C-13/C-15 oxygen bridge moiety. In addition, the EtOAc extract (GAE) and isolates (1–4,6–15) were assayed for their antiadipogenic effects in 3T3-L1 adipocytes. The results revealed that compound 9 effectively repressed adipogenesis through down-regulating the expression of major proteins (PPARγ, CEBPβ and FAS) involving differentiation and adipogenesis in 3T3-L1 adipocytes. Thus, the present study further demonstrated the antiadipogenic potential of GTs and provided a possible perspective for obesity treatment.

Inhibition of Lipid Accumulation and Cyclooxygenase-2 Expression in Differentiating 3T3-L1 Preadipocytes by Pazopanib, a Multikinase Inhibitor.

Pazopanib is a multikinase inhibitor with anti-tumor activity. As of now, the anti-obesity effect and mode of action of pazopanib are unknown. In this study, we investigated the effects of pazopanib on lipid accumulation, lipolysis, and expression of inflammatory cyclooxygenase (COX)-2 in differentiating and differentiated 3T3-L1 cells, a murine preadipocyte. Of note, pazopanib at 10 µM markedly decreased lipid accumulation and triglyceride (TG) content during 3T3-L1 preadipocyte differentiation with no cytotoxicity. Furthermore, pazopanib inhibited not only expression of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), and perilipin A but also phosphorylation of signal transducer and activator of transcription (STAT)-3 during 3T3-L1 preadipocyte differentiation. In addition, pazopanib treatment increased phosphorylation of cAMP-activated protein kinase (AMPK) and its downstream effector ACC during 3T3-L1 preadipocyte differentiation. However, in differentiated 3T3-L1 adipocytes, pazopanib treatment did not stimulate glycerol release and hormone-sensitive lipase (HSL) phosphorylation, hallmarks of lipolysis. Moreover, pazopanib could inhibit tumor necrosis factor (TNF)-α-induced expression of COX-2 in both 3T3-L1 preadipocytes and differentiated cells. In summary, this is the first report that pazopanib has strong anti-adipogenic and anti-inflammatory effects in 3T3-L1 cells, which are mediated through regulation of the expression and phosphorylation of C/EBP-α, PPAR-γ, STAT-3, ACC, perilipin A, AMPK, and COX-2.

An adiponectin receptor agonist promote osteogenesis via regulating bone-fat balance.

ObjectivesAdiponectin signalling has been considered to be a promising target to treat diabetes‐related osteoporosis. However, contradictory results regarding bone formation were observed due to the various isoforms of adiponectin. Therefore, it would be necessary to investigate the effect of adiponectin receptor signals in regulating bone‐fat balance.Materials and MethodsWe primarily applied a newly found specific activator for adiponectin receptor, AdipoRon, to treat bone metabolism‐related cells to investigate the role of Adiponectin receptor signals on bone‐fat balance. We then established femur defect mouse model and treated them with AdipoRon to see whether adiponectin receptor activation could promote bone regeneration.ResultsWe found that AdipoRon could slightly inhibit the proliferation of pre‐osteoblast and pre‐osteoclast, but AdipoRon showed no effect on the viability of mesenchymal stromal cells. AdipoRon could remarkably promote cell migration of mesenchymal stromal cells. Additionally, AdipoRon promoted osteogenesis in both pre‐osteoblasts and mesenchymal cells. Besides, AdipoRon significantly inhibited osteoclastogenesis via its direct impact on pre‐osteoclast and its indirect inhibition of RANKL in osteoblast. Moreover, mesenchymal stromal stems cells showed obviously decreased adipogenesis when treated with AdipoRon. Consistently, AdipoRon‐treated mice showed faster bone regeneration and repressed adipogenesis.ConclusionsOur study demonstrated a pro‐osteogenic, anti‐adipogenic and anti‐osteoclastogenic effect of adiponectin receptor activation in young mice, which suggested adiponectin receptor signalling was involved in bone regeneration and bone‐fat balance regulation.

Anti-adipogenic effects of interferon-gamma is mediated by a stat5-smad3 dyad in visceral adipose mesenchymal stromal cells

Anti-adipogenic effects of interferon-gamma is mediated by a stat5-smad3 dyad in visceral adipose mesenchymal stromal cells

Shrimp Oil Extracted from Shrimp Processing By-Product Is a Rich Source of Omega-3 Fatty Acids and Astaxanthin-Esters, and Reveals Potential Anti-Adipogenic Effects in 3T3-L1 Adipocytes.

The province of Newfoundland and Labrador, Canada, generates tons of shrimp processing by-product every year. Shrimp contains omega (n)-3 polyunsaturated fatty acids (PUFA) and astaxanthin (Astx), a potent antioxidant that exists in either free or esterified form (Astx-E). In this study, shrimp oil (SO) was extracted from the shrimp processing by-product using the Soxhlet method (hexane:acetone 2:3). The extracted SO was rich in phospholipids, n-3 PUFA, and Astx-E. The 3T3-L1 preadipocytes were differentiated to mature adipocytes in the presence or absence of various treatments for 8 days. The effects of SO were then investigated on fat accumulation, and the mRNA expression of genes involved in adipogenesis and lipogenesis in 3T3-L1 cells. The effects of fish oil (FO), in combination with Astx-E, on fat accumulation, and the mRNA expression of genes involved in adipogenesis and lipogenesis were also investigated. The SO decreased fat accumulation, compared to untreated cells, which coincided with lower mRNA expression of adipogenic and lipogenic genes. However, FO and FO + Astx-E increased fat accumulation, along with increased mRNA expression of adipogenic and lipogenic genes, and glucose transporter type 4 (Glut-4), compared to untreated cells. These findings have demonstrated that the SO is a rich source of n-3 PUFA and Astx-E, and has the potential to elicit anti-adipogenic effects. Moreover, the SO and FO appear to regulate adipogenesis and lipogenesis via independent pathways in 3T3-L1 cells.

Anti-adipogenic and lipid-lowering activity of piperine and epigallocatechin gallate in 3T3-L1 adipocytes

The present study was aimed to evaluate the anti-adipogenic activity of piperine (PIP) and epigallocatechin gallate (EGCG) in 3T3-L1 cells. In cytotoxicity studies, PIP and EGCG showed IC50 values of 260 and 218 µM respectively and in combination (20 µM each) did not show cytotoxicity. Treatment with PIP and EGCG (20 µM each) significantly (p<.01) inhibited cell differentiation, lipid droplets deposition and enhanced glycerol release in 3T3-L1 cells. The secreted level of leptin was decreased but adiponectin level was increased in treated 3T3-L1 cells than untreated cells. In molecular expression studies, key adipogenic genes PPAR-γ, SREBP-1c, FAS, Fab-4, C/EBP-α and HMG-CoA reductase were markedly down-regulated but UCP-1 was up-regulated in treated 3T3-L1 cells and the same trend was observed in expression levels of selected proteins. In conclusion, our results demonstrated a combination of PIP and EGCG exhibited strong anti-adipogenic and lipid lowering effect than individual treatments due to synergism.

Dillenia Indica Fruit Extract Suppressed Diet-induced Obesity in Rats by Down-regulating the mRNA Level of Proadipogenic Transcription Factors and Lipid Metabolizing Enzymes

Background: Dillenia indica (Family: Dilleniaceae) is an antioxidant-rich edible fruitbearing medicinal plant. The fruit of this plant (known as elephant apple) has many uses in traditional medicine. Objective: By considering its antioxidant content and ameliorating effects, this study aimed to evaluate the anti-adipogenic effects of D. indica fruit extract (DIFE) on high-fat diet (HFD) fed obese rats. Methods: Male Wistar rats were fed with a standard diet (SD), or high-fat diet (HFD), or HFD with 100 mg/kg or 200 mg/kg or 400 mg/kg DIFE for 8 weeks. The fruit extract was given orally by feeding gavage. The body weight, liver weight, visceral fat weight, plasma lipids, and oxidative stress-related parameters were measured. The mRNA level of different adipogenesis related transcription factors, lipogenic and lipolytic enzymes was also evaluated. Results: Consumption of DIFE daily (400 mg/kg) for 8 weeks resulted in a significant reduction of high-fat diet-induced body weight, liver weight, visceral fat weight, total cholesterol, and LDL-cholesterol level. High-fat diet-mediated elevation of oxidative stress markers was also lowered, with a parallel augmentation of the activities of antioxidant enzymes, due to 400 mg/kg DIFE feeding. DIFE also down-regulated the mRNA level of important pro-adipogenic factors like PPARγ, LXRα, and SREBP1c which consequently downregulated the transcript levels of lipogenic enzymes: ACC, FAS, HMGCR, and DGAT. The transcript level of lipolytic enzyme, HSL was also down-regulated in 400 mg/kg DIFE-fed rats. Conclusion: These findings indicate that the antioxidant-rich ethanolic extract of D. indica fruit can down-regulate the gene expression of pro-adipogenic transcription factors and lipid metabolizing enzymes and thus can suppress diet-induced obesity in Wistar rat.

Oral intake of Lactobacillus plantarum L-14 extract alleviates TLR2- and AMPK-mediated obesity-associated disorders in high-fat-diet-induced obese C57BL/6J mice.

ObjectivesWhether periodic oral intake of postbiotics positively affects weight regulation and prevents obesity‐associated diseases in vivo is unclear. This study evaluated the action mechanism of Lactobacillus plantarum L‐14 (KTCT13497BP) extract and the effects of its periodic oral intake in a high‐fat‐diet (HFD) mouse model.Materials and methodsMouse pre‐adipocyte 3T3‐L1 cells and human bone marrow mesenchymal stem cells (hBM‐MSC) were treated with L‐14 extract every 2 days during adipogenic differentiation, and the mechanism underlying anti‐adipogenic effects was analysed at cellular and molecular levels. L‐14 extract was orally administrated to HFD‐feeding C57BL/6J mice every 2 days for 7 weeks. White adipose tissue was collected and weighed, and liver and blood serum were analysed. The anti‐adipogenic mechanism of exopolysaccharide (EPS) isolated from L‐14 extract was also analysed using Toll‐like receptor 2 (TLR2) inhibitor C29.ResultsL‐14 extract inhibited 3T3‐L1 and hBM‐MSC differentiation into mature adipocytes by upregulating AMPK signalling pathway in the early stage of adipogenic differentiation. The weight of the HFD + L‐14 group (31.51 ± 1.96 g) was significantly different from that of the HFD group (35.14 ± 3.18 g). L‐14 extract also significantly decreased the serum triacylglycerol/high‐density lipoprotein cholesterol ratio (an insulin resistance marker) and steatohepatitis. In addition, EPS activated the AMPK signalling pathway by interacting with TLR2, consequently inhibiting adipogenesis.ConclusionsEPS from L‐14 extract inhibits adipogenesis via TLR2 and AMPK signalling pathways, and oral intake of L‐14 extract improves obesity and obesity‐associated diseases in vivo. Therefore, EPS can be used to prevent and treat obesity and metabolic disorders.

Effects of Ginsenoside Rg3 on Inhibiting Differentiation, Adipogenesis, and ER Stress-Mediated Cell Death in Brown Adipocytes.

Objectives Ginsenoside Rg3 (Rg3), a main active component of Panax ginseng, has various therapeutic properties in literatures, and it has been studied for its potential use in obesity control due to its antiadipogenic effects in white adipocytes. However, little is known about its effects on brown adipocytes. Methods The mechanisms through which Rg3 inhibits differentiation, adipogenesis, and ER stress-mediated cell death in mouse primary brown adipocytes (MPBAs) are explored. Results Rg3 significantly induced cytotoxicity in differentiated MPBAs but not in undifferentiated MPBAs. Rg3 treatment downregulated the expression of differentiation and adipogenesis markers and the level of perilipin in MPBAs while upregulating the expression of lipolytic Kruppel-like factor genes. Rg3 also induced lipolysis and efflux of triglycerides from MPBAs and subsequently increased proinflammatory cytokine levels. Notably, Rg3 treatment resulted in elevation of ER stress and proapoptotic markers in MPBAs. Conclusions Our results demonstrate that Rg3 is able to selectively exert cytotoxicity in differentiated MPBAs while leaving undifferentiated MPBAs intact, resulting in the induction of ER stress and subsequent cell death in MPBAs via regulation of various genes related to adipocyte differentiation, adipogenesis, lipolysis, and inflammation. These results indicate that further studies on the potential therapeutic applications of Rg3 are warranted.

Syringin: A Phenylpropanoid Glycoside Compound in Cirsium brevicaule A. GRAY Root Modulates Adipogenesis.

Cirsium brevicaule A. GRAY is a wild perennial herb, and its roots (CbR) have traditionally been used as both food and medicine on the Japanese islands of Okinawa and Amami. The present study evaluated the antiadipogenic effect of CbR using mouse embryonic fibroblast cell line 3T3-L1 from JCRB cell bank. Dried CbR powder was serially extracted with solvents of various polarities, and these crude extracts were tested for antiadipogenic activity. Treatment with the methanol extract of CbR showed a significant suppression of lipid accumulation in 3T3-L1 cells. Methanol extract of CbR was then fractionated and subjected to further activity analyses. The phenylpropanoid glycosidic molecule syringin was identified as an active compound. Syringin dose dependently suppressed lipid accumulation of 3T3-L1 cells without cytotoxicity, and significantly reduced the expressions of peroxisome proliferator-activated receptor gamma, the master regulator of adipogenesis, and other differentiation markers. It was demonstrated that syringin effectively enhanced the phosphorylation of the AMP-activated protein kinase and acetyl-CoA carboxylase. These results indicate that syringin attenuates adipocyte differentiation, adipogenesis, and promotes lipid metabolism; thus, syringin may potentially serve as a therapeutic candidate for treatment of obesity.

Extract of Acalypha australis L. inhibits lipid accumulation and ameliorates HFD-induced obesity in mice through regulating adipose differentiation by decreasing PPARγ and CEBP/α expression.

BackgroundObesity is a principal risk factor for the development of type 2 diabetes and cardiovascular diseases. Natural plants and/or foods play an important role in the management of obesity. Acalypha australis L. (AAL) is a kind of potherb popular among Asian populations, and it is also consumed as a food ingredient and traditional herbal medicine.ObjectiveWe investigated the effects of water extract from AAL on high-fat-diet (HFD)-induced obese mice and 3T3-L1 adipocytes to develop a new functional food material.DesignNine-week-old male mice were randomly divided into control (chow diet, n = 6) and HFD (n = 30) group. From 12-weeks onward, mice in the HFD group were further separated into model (saline, 6 mL/kg), simvastatin (0.11 mg/mL, 6 mL/kg), and AAL treatment (low, middle, and high dosage: 300, 600, and 900 mg/kg) group, with 6 animals per group, while mice in the control group were treated with saline (6 mL/kg). Food intake, body/fat weight, liver/kidney indexes, and lipid profiles were determined. Tissues were fixed with formalin for pathological examination. Western blotting and PCR were performed to evaluate the protein and mRNA expression in 3T3-L1 adipocytes. Oil Red O staining was used to determine lipid accumulation.ResultsAAL administration significantly suppressed body weight gain, and reduced fat pad weight and Lee’s index in obese mice, but had no effect on liver/kidney index. AAL also reduced serum cholesterol, triglyceride, and LDL-C and increased HDL-C levels. Histological analysis revealed that AAL significantly ameliorated lipid accumulation in the liver and subcutaneous adipose tissue. In vitro, Oil Red O staining showed that AAL inhibited adipose differentiation by down-regulating the gene and protein expression of PPARγ and C/EBPα. AAL also reversed HFD-induced intestinal dysbacteriosis.ConclusionAAL water-soluble extract has a significant anti-adipogenic effect in the HFD-induced obese mice model.

Extract of Acalypha australis L. inhibits lipid accumulation and ameliorates HFD-induced obesity in mice through regulating adipose differentiation by decreasing PPARγ and CEBP/α expression

Background: Obesity is a principal risk factor for the development of type 2 diabetes and cardiovascular diseases. Natural plants and/or foods play an important role in the management of obesity. Acalypha australis L. (AAL) is a kind of potherb popular among Asian populations, and it is also consumed as a food ingredient and traditional herbal medicine.&#x0D; Objective: We investigated the effects of water extract from AAL on high-fat-diet (HFD)-induced obese mice and 3T3-L1 adipocytes to develop a new functional food material.&#x0D; Design: Nine-week-old male mice were randomly divided into control (chow diet, n = 6) and HFD (n = 30) group. From 12-weeks onward, mice in the HFD group were further separated into model (saline, 6 mL/ kg), simvastatin (0.11 mg/mL, 6 mL/kg), and AAL treatment (low, middle, and high dosage: 300, 600, and 900 mg/kg) group, with 6 animals per group, while mice in the control group were treated with saline (6 mL/ kg). Food intake, body/fat weight, liver/kidney indexes, and lipid profiles were determined. Tissues were fixed with formalin for pathological examination. Western blotting and PCR were performed to evaluate the protein and mRNA expression in 3T3-L1 adipocytes. Oil Red O staining was used to determine lipid accumulation.&#x0D; Results: AAL administration significantly suppressed body weight gain, and reduced fat pad weight and Lee’s index in obese mice, but had no effect on liver/kidney index. AAL also reduced serum cholesterol, triglyceride, and LDL-C and increased HDL-C levels. Histological analysis revealed that AAL significantly ameliorated lipid accumulation in the liver and subcutaneous adipose tissue. In vitro, Oil Red O staining showed that AAL inhibited adipose differentiation by down-regulating the gene and protein expression of PPARγ and C/EBPα. AAL also reversed HFD-induced intestinal dysbacteriosis.&#x0D; Conclusion: AAL water-soluble extract has a significant anti-adipogenic effect in the HFD-induced obese mice model.

Biotransformation of whey by Weissella cibaria suppresses 3T3-L1 adipocyte differentiation

Biotransformation, the structural modification of chemical compounds, has proved to be an indispensable tool in providing beneficial health effects. Although the health benefits of biotransformation using plant sources has been widely studied, the anti-adipogenic effect of biotransformed dairy products, such as whey, have not yet been demonstrated. Here, we investigated the anti-adipogenic effect of whey biotransformed by Weissella cibaria in 3T3-L1 adipocytes. Weissella cibaria-biotransformed whey considerably reduced the accumulation of lipid droplets and intracellular triglycerides in 3T3-L1 cells. In the presence of W. cibaria-biotransformed whey, the mRNA and protein expression of a key transcription factor, peroxisome proliferator-activated receptor γ (PPARγ), for adipogenesis was markedly suppressed in 3T3-L1 cells. Additionally, W. cibaria-biotransformed whey also decreased the mRNA and protein expressions of lipoprotein lipase and adipocyte fatty acid-binding protein, which are regulated by PPARγ. Moreover, W. cibaria-biotransformed whey inhibited the expression of adipokines, resistin, and leptin. Collectively, these results suggest that whey biotransformed by W. cibaria has the potential to exert anti-adipogenic effects by inhibiting intracellular signaling events of adipogenic-related transcription factors and target genes.

Piceatannol Is Superior to Resveratrol at Suppressing Adipogenesis in Human Visceral Adipose-Derived Stem Cells.

Resveratrol (3,4′,5-trans-trihydroxystilbene) and piceatannol (3,3′,4′,5-trans-tetraphydroxystilbene) are major stilbene compounds that are predominantly present in various natural foods, such as berries and fruits. Both phytochemical compounds are consumed as dietary supplements to prevent various metabolic diseases and for their anti-aging properties. Adipose-derived stem cells from human visceral adipose tissue (vASCs) are a useful in vitro model for evaluating their adipogenic effect. Treatment with resveratrol and piceatannol significantly inhibited lipid accumulation in vASCs. Their effective concentrations were 5, 10, and 20 μM for inhibiting adipogenesis of vASCs. Interestingly, despite the similar chemical structures of the two compounds, piceatannol showed a higher anti-adipogenic effect at 20 μM than resveratrol in vASCs. Moreover, the inhibitory capacity of lipid droplet generation was higher for piceatannol at 20 μM than that of resveratrol. Piceatannol significantly attenuated the expression level of adipogenic markers (e.g., CCAAT/enhanced binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), and adipocyte fatty acid binding protein (aP2)) compared to resveratrol at the mRNA and protein levels. These results suggest that piceatannol is a superior anti-adipogenic compound compared to resveratrol in the vASC model of visceral obesity.

An in vitro mechanistic approach towards understanding the distinct pathways regulating insulin resistance and adipogenesis by apocynin

Adipogenesis is a cascade of processes that entail the differentiation of fibroblasts into mature adipocytes, which results in the accumulation of triglycerides in the adipose cells due to high dietary supplements. This physiological condition increases the risk of type 2 diabetes. Apocynin (4-hydroxy-3-methoxyacetophenone), an organic compound from the root extracts of the medicinal herb Picrorhiza kurroa, has been used in various experimental studies. The current study focuses on deciphering the cellular and molecular mechanisms interlinking obesity and diabetes by validating the various key targets involved in insulin signaling and adipogenesis. Apocynin exhibited enhanced glucose uptake and decreased lipid accumulation in the adipocytes. Furthermore, the expression of molecular markers involved in the insulin signaling pathway, such as IRTK, IRS-1, PI3K, GLUT-4, and the adipogenic pathway, such as PPAR α, adiponectin, C/EBP-α and SREBP1C, by qPCR supported our hypothesis largely. Apocynin mimicked insulin in the insulin-signaling pathway by showing equivalent gene expression. It ameliorated adipogenesis by downregulating the key markers in the adipogenic pathway. Corroborating the hypothesis that Apocynin is antihyperlipidemic in nature, it reduced the expression of PPARα and adiponectin. These results substantiate that Apocynin exerts anti-diabetic and anti-adipogenic effects by regulating resistin and antioxidant enzyme levels in vitro.

Chronic Oleoylethanolamide Treatment Decreases Hepatic Triacylglycerol Level in Rat Liver by a PPARγ/SREBP-Mediated Suppression of Fatty Acid and Triacylglycerol Synthesis.

Oleoylethanolamide (OEA) is a naturally occurring bioactive lipid belonging to the family of N-acylethanolamides. A variety of beneficial effects have been attributed to OEA, although the greater interest is due to its potential role in the treatment of obesity, fatty liver, and eating-related disorders. To better clarify the mechanism of the antiadipogenic effect of OEA in the liver, using a lipidomic study performed by 1H-NMR, LC-MS/MS and thin-layer chromatography analyses we evaluated the whole lipid composition of rat liver, following a two-week daily treatment of OEA (10 mg kg−1 i.p.). We found that OEA induced a significant reduction in hepatic triacylglycerol (TAG) content and significant changes in sphingolipid composition and ceramidase activity. We associated the antiadipogenic effect of OEA to decreased activity and expression of key enzymes involved in fatty acid and TAG syntheses, such as acetyl-CoA carboxylase, fatty acid synthase, diacylglycerol acyltransferase, and stearoyl-CoA desaturase 1. Moreover, we found that both SREBP-1 and PPARγ protein expression were significantly reduced in the liver of OEA-treated rats. Our findings add significant and important insights into the molecular mechanism of OEA on hepatic adipogenesis, and suggest a possible link between the OEA-induced changes in sphingolipid metabolism and suppression of hepatic TAG level.

Neferine suppresses autophagy-induced inflammation, oxidative stress and adipocyte differentiation in Graves' orbitopathy.

Previous studies in Graves’ orbitopathy (GO) patient‐derived fibroblasts showed that inhibition of autophagy suppresses adipogenic differentiation. Autophagy activation is associated with inflammation, production of reactive oxygen species and fibrosis. Neferine is an alkaloid extracted from Nelumbo nucifera, which induces Nrf2 expression and inhibits autophagy. Here, we have elucidated the role of neferine on interleukin (IL)‐13‐induced autophagy using patient‐derived orbital fibroblasts as an in vitro model of GO. GO patient‐derived orbital fibroblasts were isolated and cultured to generate an in vitro model of GO. Autophagy was determined by Western blot detection of the markers such as Beclin‐1, Atg‐5 and LC3 and by immunofluorescence detection of autophagosome formation. Analysis of differentiation towards an adipogenic lineage was performed by Oil red O staining. The expression of inflammatory factors was detected by ELISA and semiquantitative RT‐PCR. Neferine inhibited autophagy in GO orbital fibroblasts, as indicated by the suppression of IL‐13‐induced autophagosome formation, overexpression of autophagy markers, increased LC3‐II/LC3‐I levels and finally down‐regulation of p62. Neferine suppressed IL‐13‐induced inflammation, ROS generation, fibrosis and adipogenic differentiation in GO patient‐derived orbital fibroblasts. The anti‐inflammatory, antioxidant and antiadipogenic effects of neferine were accompanied by the up‐regulation of Nrf2. These results indicated that orbital tissue remodelling and inflammation in GO may be mediated by autophagy, and neferine suppressed autophagy‐related inflammation and adipogenesis through a mechanism involving Nrf2.