Fatty Acid Binding Protein aP2 Research Articles

Leuconostoc Citreum Inhibits Adipogenesis and Lipogenesis by Inhibiting p38 MAPK/Erk 44/42 and Stimulating AMPKα Signaling Pathways.

Probiotics provide a range of health benefits. Several studies have shown that using probiotics in obesity treatment can reduce bodyweight. However, such treatments are still restricted. Leuconostoc citreum, an epiphytic bacterium, is widely used in a variety of biological applications. However, few studies have investigated the role of Leuconostoc spp. in adipocyte differentiation and its molecular mechanisms. Therefore, the objective of this study was to determine the effects of cell-free metabolites of L. citreum (LSC) on adipogenesis, lipogenesis, and lipolysis in 3T3-L1 adipocytes. The results showed that LSC treatment reduced the accumulation of lipid droplets and expression levels of CCAAT/ enhancer-binding protein-α & β (C/EBP-α & β), peroxisome proliferator-activated receptor-γ (PPAR-γ), serum regulatory binding protein-1c (SREBP-1c), adipocyte fatty acid binding protein (aP2), fatty acid synthase (FAS), acetyl CoA carboxylase (ACC), resistin, pp38MAPK, and pErk 44/42. However, compared to control cells, adiponectin, an insulin sensitizer, was elevated in adipocytes treated with LSC. In addition, LSC treatment increased lipolysis by increasing pAMPK-α and suppressing FAS, ACC, and PPAR-γ expression, similarly to the effects of AICAR, an AMPK agonist. In conclusion, L. citreum is a novel probiotic strain that can be used to treat obesity and its associated metabolic disorders.

Inhibitory Effects of Hydrolysable Tannins on Lipid Accumulation in 3T3-L1 Cells.

Obesity is currently the most common cause of metabolic diseases including type 2 diabetes and hyperlipidemia. Obesity results from excess lipid accumulation in adipose tissue. Several studies have investigated the inhibitory effects of natural plant-derived products on adipocyte differentiation and lipid accumulation. In this study, we examined the effect of hydrolysable tannins composed of gallic acid and glucose on adipocyte differentiation in 3T3-L1 cells. 1,2,3,4,6-Penta-O-galloyl-β-D-glucose (PGG) (1), a representative gallotannin, inhibited lipid accumulation in 3T3-L1 cells, whereas ellagitannins (tellimagrandin I, eugeniin and casuarictin) did not. The expression of adipocyte differentiation-related genes, including peroxisome proliferator activator γ2 (Pparγ2), CCAAT/enhancer binding protein α (C/EBPα) and adipocyte fatty acid binding protein (aP2), was significantly suppressed in PGG (1)-treated 3T3-L1 cells beginning at day 2 after induction of differentiation. While PGG (1) did not directly reduce Pparγ2 expression, it reduced the expression of its target genes in mature adipocytes. In addition, PGG (1) treatment inhibited mitotic clonal expansion, one of earliest events of adipocyte differentiation. These findings indicate that PGG (1) has an inhibitory effect on adipocyte differentiation through the suppression of mitotic clonal expansion.

Derhamnosylmaysin Inhibits Adipogenesis via Inhibiting Expression of PPARγ and C/EBPα in 3T3-L1 Cells.

We investigated the effects of derhamnosylmaysin (DM) on adipogenesis and lipid accumulation in 3T3-L1 adipocytes. Our data showed that DM inhibited lipid accumulation and adipocyte differentiation in 3T3-L1 cells. Treatment of 3T3-L1 adipocytes with DM decreased the expression of major transcription factors, such as sterol regulatory element-binding protein-1c (SREBP-1c), the CCAAT-enhancer-binding protein (CEBP) family, and peroxisome proliferator-activated receptor gamma (PPARγ), in the regulation of adipocyte differentiation. Moreover, the expression of their downstream target genes related to adipogenesis and lipogenesis, including adipocyte fatty acid-binding protein (aP2), lipoprotein lipase (LPL), stearyl-CoA-desaturase-1 (SCD-1), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS), was also decreased by treatment with DM during adipogenesis. Additionally, DM attenuated insulin-stimulated phosphorylation of Akt. These results first demonstrated that DM inhibited adipogenesis and lipogenesis through downregulation of the key adipogenic transcription factors SREBP-1c, the CEBP family, and PPARγ and inactivation of the major adipogenesis signaling factor Akt, which is intermediated in insulin. These studies demonstrated that DM is a new bioactive compound for antiadipogenic reagents for controlling overweight and obesity.

Anti-Obesity Potential of Ponciri Fructus: Effects of Extracts, Fractions and Compounds on Adipogenesis in 3T3-L1 Preadipocytes.

Background: Ponciri Fructus, a crude drug consisting of the dried immature fruits of Poncirus trifoliata (L.) Raf., is a popular folk medicine used for the treatment of allergy and gastrointestinal disorders in Korea and China. In this study, the anti-adipogenic activity of extracts and isolated compounds were evaluated using 3T3-L1 preadipocytes. Methods: Dried immature fruits were extracted and fractionated into n-hexane, ethyl acetate (EtOAc), n-butanol and water-soluble fractions. The ethanol extract and fractions were tested for anti-adipogenic activity in the 3T3-L1 cell line. The active fractions (n-hexane and EtOAc fractions) were further subjected to chromatographic techniques to isolate and identify active compounds. Furthermore, the isolated compounds were evaluated for their anti-adipogenic activity. Results: Altogether, seven compounds, including two flavonoids, one phytosteroid and four coumarin derivatives, were isolated. Ethanol extract, n-hexane fraction, EtOAc fraction and three isolated compounds (phellopterin, oxypeucedanin and poncirin) showed significant anti-adipogenic activity as observed by reduced lipid deposition in differentiated 3T3-L1 cells. Further, oxypeucedanin downregulated the key adipogenic markers, such as peroxisome proliferator-activated receptors proteins γ (PPAR-γ), sterol response element binding proteins-1 (SREBP-1), CCAAT/enhancer binding proteins-α (C/EBP-α), adipocyte-specific lipid binding proteins (FABP-4), adipocyte fatty acid binding proteins (aP2), lipoprotein lipase (LPL) and leptin. Conclusion: This study indicated that the ethanol extract, hexane fraction and ethyl acetate fraction of P. trifoliata fruits possess strong anti-adipogenic activity, containing the active compounds such as phellopterin, oxypeucedanin and poncirin. Further research is recommended to explore their efficacy and safety in animal and clinical models.

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.

Natural Extracts from White Common Bean (Phaseolus vulgaris L.) Inhibit 3T3-L1 Adipocytes Differentiation

Background: Recent studies have shown that the consumption of common bean (Phaseolus vulgaris L.) foods plays an essential role in the prevention and treatment of obesity. Methods: In this study, different natural extracts that include common bean polyphenol-rich extract (CBP), α-amylase inhibitor-rich extract (α-AIE), and non-starch polysaccharides-rich extract (NSP) were isolated. Their effects on 3T3-L1 adipocytes differentiation were evaluated, respectively. Results: The results showed that CPB reduced the lipid content in the mature adipocytes to 79.29% (150 μg/mL) and 35.13% (300 μg/mL), and α-AIE reduced it to 90.20% (2 mg/mL) and 68.28% (4 mg/mL), while NSP exhibited an auxo-action, suggesting that both CBP and a-AIE inhibited 3T3-L1 adipocytes differentiation. Additionally, CBP significantly suppressed (p < 0.05) the mRNA expression level and the protein expression level of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT-enhancer-binding protein α (C/EBPα), sterol-regulatory element binding proteins 1 c (SREBP-1c), lipoprotein lipase (LPL), and fatty acid binding protein (ap2). Meanwhile, α-AIE only showed significant suppression effects on PPARγ, C/EBPα, and ap2 at the high dose of 4 mg/mL (p < 0.05). Conclusions: These findings indicate that CBP, from white common bean, might be the major component responsible for the inhibitory effects on adipocyte differentiation.

Effect of Astaxanthin on the Inhibition of Lipid Accumulation in 3T3-L1 Adipocytes via Modulation of Lipogenesis and Fatty Acid Transport Pathways.

Obesity is defined as a condition of excessive fat tissue accumulation. It was the major factor most closely associated with lifestyle-related diseases. In the present study, we investigated the effect of astaxanthin on the inhibition of lipid accumulation in 3T3-L1 adipocytes. 3T3-L1 adipocytes were treated with 0–25 µg/mL of astaxanthin for 0–48 h. The result indicated that astaxanthin significantly decreased the oil Red O stained material (OROSM), intracellular triglyceride accumulation, and glycerol 3-phosphate dehydrogenase (GPDH) activity in 3T3-L1 adipocytes (p < 0.05). At the molecular level, astaxanthin significantly down-regulated the mRNA expression of peroxisome proliferator-activated receptor-γ (PPARγ) in 3T3-L1 adipocytes (p < 0.05). Moreover, target genes of PPARγ on the inhibition of lipogenesis, such as Acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), fatty acid binding protein (aP2), cluster of differentiation 36 (CD36), and lipoprotein lipase (LPL) in 3T3-L1 adipocytes were significantly down-regulated at a time-dependent manner (p < 0.05). These results suggested that astaxanthin efficiently suppressed lipid accumulation in 3T3-L1 adipocytes and its action is associated with the down-regulation of lipogenesis-related genes and the triglyceride accumulation in 3T3-L1 adipocytes. Therefore, astaxanthin can be developed as a potential nutraceutical ingredient for the prevention of obesity in a niche market.

Contrary Roles of Wnt/β-Catenin Signaling in BMP9-Induced Osteogenic and Adipogenic Differentiation of 3T3-L1 Preadipocytes.

Our previous study revealed that 3T3-L1 preadipocytes can differentiate to either osteoblasts or adipocytes in response to bone morphogenic protein 9 (BMP9). In the present study, we try to further investigate whether the Wnt/β-catenin signaling plays a crucial role in this process. It was found that BMP9 effectively activated the Wnt/β-catenin signaling, and induced the expression levels of certain canonical Wnt ligands and their receptors in preadipocytes. Exogenous expression of β-catenin, Wnt1, Wnt3a, and Wnt10b potentiated BMP9-induced alkaline phosphatase (ALP) activity, while β-catenin knockdown or Dickkopf 1 (Dkk1) diminished BMP9-induced ALP activity. Moreover, it was demonstrated that β-catenin overexpression promoted BMP9-induced mineralization, and increased the expression levels of late osteogenic markers osteopontin and osteocalcin. Furthermore, β-catenin inhibited BMP9-induced lipid accumulation and the adipogenic marker adipocyte fatty acid binding protein (aP2). The cell-implantation assay results identified that β-catenin not only augmented BMP9-induced ectopic bone formation, but also blocked adipogenesis in vivo. Mechanistically, it was found that β-catenin and BMP9 synergistically stimulated the osteogenic transcription factors runt-related transcription factor 2 (Runx2) and Osterix (OSX). However, BMP9-induced adipogenic transcription factors, peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT enhancer-binding protein α (C/EBPα), were inhibited by β-catenin. Therefore, these findings suggested that the Wnt/β-catenin signaling, potentially via the modulation of osteogenic and adipogenic transcriptional factors, exerts an opposite effect on BMP9-induced osteogenic and adipogenic differentiation in preadipocytes.

A Pea (Pisum sativum L.) Seed Vicilins Hydrolysate Exhibits PPARγ Ligand Activity and Modulates Adipocyte Differentiation in a 3T3-L1 Cell Culture Model.

Legume consumption has been reported to induce beneficial effects on obesity-associated metabolic disorders, but the underlying mechanisms have not been fully clarified. In the current work, pea (Pisum sativum L.) seed meal proteins (albumins, legumins and vicilins) were isolated, submitted to a simulated gastrointestinal digestion, and the effects of their hydrolysates (pea albumins hydrolysates (PAH), pea legumins hydrolysates (PLH) and pea vicilin hydrolysates (PVH), respectively) on 3T3-L1 murine pre-adipocytes were investigated. The pea vicilin hydrolysate (PVH), but not native pea vicilins, increased lipid accumulation during adipocyte differentiation. PVH also increased the mRNA expression levels of the adipocyte fatty acid-binding protein (aP2) and decreased that of pre-adipocyte factor-1 (Pref-1) (a pre-adipocyte marker gene), suggesting that PVH promotes adipocyte differentiation. Moreover, PVH induced adiponectin and insulin-responsive glucose transporter 4 (GLUT4) and stimulated glucose uptake. The expression levels of peroxisome proliferator-activated receptor γ (PPARγ), a key regulator of adipocyte differentiation, were up-regulated in 3T3-L1 cells treated with PVH during adipocyte differentiation. Finally, PVH exhibited PPARγ ligand activity. Lactalbumin or other pea hydrolysates (PAH, PLH) did not exhibit such effects. These findings show that PVH stimulates adipocyte differentiation via, at least in part, the up-regulation of PPARγ expression levels and ligand activity. These effects of PVH might be relevant in the context of the beneficial health effects of legume consumption in obesity-associated metabolic disorders.

Inhibition of 3T3-L1 Adipocyte Differentiation by D-allulose

Obesity is a serious problem in modern society and its prevalence continues to increase worldwide, resulting in metabolic disorder related diseases. D-allulose, a sugar substitute, boasts a near-zero calorie value and regulates lipid accumulation. However, the molecular mechanism of D-allulose at the cellular level has not been fully elucidated. In this study, we investigated the effect of D-allulose on 3T3-L1 adipocyte differentiation. D-allulose inhibits differentiation of 3T3-L1 preadipocytes into mature adipocytes, as examined by Oil Red O staining. The mRNA levels of genes involved in lipogenesis, including fatty acid synthase (FAS) and adipocyte fatty acid-binding protein (aP2), were significantly decreased and intracellular triglyceride (TG) content was markedly reduced with D-allulose treatment. We also monitored the activity of major adipogenic transcription factors–CREB, SREBP-1c, and PPARψ–using 3T3-L1 reporter cell lines that were constructed to secrete Gaussia luciferase upon binding of a transcription factor to its DNA binding element. Collectively, D-allulose suppresses adipocyte differentiation and lipid accumulation through regulating adipogenic transcription factors and may have anti-obesity potential.

Decursin and Decursinol Angelate Suppress Adipogenesis through Activation of β-catenin Signaling Pathway in Human Visceral Adipose-Derived Stem Cells.

Visceral adiposity is closely associated with metabolic disorders and cardiovascular diseases. Angelica gigas Nakai (AGN) has been reported to possess anti-obesity effects and higher amounts of coumarin compounds are present in AGN. However, the active compounds suppressing adipogenesis in AGN and mechanisms of action have not been investigated in adipose-derived stem cells (ASCs) isolated from visceral adipose tissue (VAT). Among four coumarin compounds of AGN, decursin (D) and decursinol angelate (DA) significantly inhibited adipocyte differentiation from ASCs. D and DA downregulated CCAAT/enhancer binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), adipocyte fatty acid binding protein (aP2), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC) at both mRNA and protein levels. Next, treatment with adipogenic differentiation medium (ADM) on ASCs downregulated β-catenin expression at protein level, while addition of D and DA could restore protein expression and nuclear translocation of β-catenin suppressed by ADM. D and DA treatment on ADM treated ASCs increased inhibitory phosphorylation of Glycogen synthase kinase (GSK)-3β, thereby preventing β-catenin from degradation. Additionally, si-β-catenin transfection significantly upregulated protein expression of C/EBPα and PPARγ, alleviating the anti-adipogenic effect of D and DA on ADM treated ASCs. Overall, D and DA, active compounds from AGN, suppressed adipogenesis through activation of β-catenin signaling pathway in ASCs derived from human VAT, possibly using as natural anti-visceral adiposity agents.

OR01-1 Leveraging Immunometabolic Control to Prevent and Treat Obesity Related Asthma

Asthma is a chronic inflammatory disease of the airways with an increasing prevalence but limited treatment options. Although the pathogenesis is not fully understood, it has a major immunometabolic component including contribution of lipid mediators to airway inflammation. Interestingly, accumulating evidence implicates obesity as a critical risk factor for asthma where these lipid mediators are upregulated. However, how obesity leads to asthma remains a critical but poorly understood area. There is a great need for novel treatments for obesity-related asthma as this group of patients are less-responsive to conventional therapies. The fatty acid binding protein aP2 is a fundamental immunometabolic regulator, which is increased in obese mice and humans. aP2 deficiency in mice improves the dysregulated metabolic outcomes of obesity and related diseases such as diabetes and atherosclerosis, which share similar lipid derangements and immunometabolic underpinnings. Moreover, we reported that aP2 secreted from adipose tissue acts as a hormone, supporting inter-organ communication. We and others have shown that increased serum aP2 levels strongly correlate with poor metabolic, inflammatory and cardiovascular outcomes in multiple independent human studies. Lastly, humans who carry a haploinsufficiency allele of aP2 have reduced risk for developing dyslipidemia, diabetes, and cardiovascular disease. Together, these findings indicate that the biological functions of aP2 are conserved and highly relevant to human pathophysiology. Interestingly, in recent studies we detected increased expression of aP2 in lung and bronchoalveolar lavage fluid (BALF) in obese mice. Strikingly, severely obese (ob/ob) aP2 deficient mice were markedly protected against obesity-related airway hyperresponsiveness. These data strongly support that aP2 is a mediator of this unique form of airway disease associated with obesity in experimental models. To evaluate the translational implications of these observations, we measured serum aP2 in humans and found 25.4% higher aP2 concentrations (54.5 ± 19.2 vs 43.4 ± 20.1 ng/ml *p<0.05) in overweight and obese asthmatics compared to obese non-asthmatics. Importantly, higher levels of serum aP2 was positively correlated with asthma status only in overweight and obese individuals, whereas there was no significant difference between lean asthmatics vs non-asthmatics. (Groups; non-asthmatics and asthmatics BMI<25 vs BMI>25, n= 510, 15, 370, 15, respectively, analyzed by two-way ANOVA *p<0.05). The frequency of asthma was also 8% higher (50% vs 42%) in overweight and obese group as compared to lean subjects. With this line of investigation, we generated critical insights into obesity related asthma pathogenesis and showing that secreted aP2 might represent a well-validated and promising target for the development of a novel therapeutic strategy in humans.

Rotenoisin A is a novel anti-adipogenic compound

The purpose of this study was to investigate the mechanisms underlying the inhibitory effects of rotenoisin A on adipogenesis in 3T3-L1 preadipocytes. 3T3-L1 cells were treated with rotenoisin A for 8 days after the induction of differentiation. Oil-red O staining showed that rotenoisin A significantly inhibited DMI-induced lipid accumulation and adipocyte differentiation. We found that rotenoisin A treatment of 3T3-L1 preadipocytes significantly reduced the mRNA and protein levels of the key adipocyte-specific transcription factors C/EBPβ, C/EBPα, and PPARγ and markedly inhibited the expression of fatty acid-binding protein (aP2), fatty acid synthase (FAS), and lipoprotein lipase (LPL). Furthermore, we observed that rotenoisin A substantially increased the phosphorylation of AMP-activated protein kinase (AMPK) and its downstream target phosphorylated acetyl CoA carboxylase (ACC). However, co-treatment with Compound C, an AMPK inhibitor, reversed the rotenoisin A-induced inhibition of the expression of the adipogenic transcription factors C/EBPα and PPARγ and decreased the levels of phosphorylated AMPK in differentiated 3T3-L1 cells. These results demonstrated that the anti-adipogenesis mechanism involves the down-regulation of critical adipogenic transcription factors, including C/EBPβ, C/EBPα, and PPARγ, through activation of the AMPK signaling pathway by rotenoisin A.

Acrylamide induces adipocyte differentiation and obesity in mice

Obesity is a critical risk factor for various diseases including type II diabetes, cerebral infarction, cardiovascular diseases, and various cancers. Acrylamide (ACR) is present in wide range of foods, including fried potato products, root vegetables, bakery products, chips, cakes, cereals, and coffee. In this study, ACR treatment dramatically increased the accumulation of lipid droplets. We also examined expression levels of peroxisome proliferator-activated receptors γ (PPARγ), CCAAT enhancer binding protein α (c/EBPα), and CCAAT enhancer binding protein β (c/EBPβ) as adipogenic transcription factors for adipocyte differentiation. They were dose-dependently increased by treatment of ACR. Moreover, effects of ACR on mitogen-activated protein kinases (MAPKs) and 5′ AMP-activated protein kinase (AMPK)-Acetyl-CoA carboxylase (ACC) activation were investigated. Results also showed that ACR induced phosphorylation of MAPKs and AMPK-ACC. ACR also induced expression of adipocyte fatty acid-binding protein (aP2), lipoprotein lipase (LPL), sterol regulatory element-binding protein (SREBP)-1c, and fatty acid synthase (FAS). Exposure of ACR to high fat diet (HFD)-fed mice significantly increased body weight, organ weight, and fat mass of mice. Collectively, these result showed that ACR can act as an enhancer of adipocyte. Therefore, we suggest that up-regulation of the adipogenesis by ACR may be related to the regulation of the MAPKs and AMPK-ACC pathway.

Astragalus Polysaccharide Improves Insulin Sensitivity via AMPK Activation in 3T3-L1 Adipocytes.

Astragalus polysaccharide (APS) is an important bioactive component of Astragalus membranaceus which is used as an anti-diabetes herb in traditional Chinese medicine. The objective of this study was to investigate the effects and mechanisms of APS on insulin-sensitizing of adipocytes. Mouse 3T3-L1 preadipocytes were used as a model. The results showed that APS increased preadipocytes proliferation in a dose dependent manner, and 0.1 μg/mL APS sufficiently increased Proliferating Cell Nuclear Antigen (PCNA) content (p < 0.01). Moreover, APS enhanced intracellular lipid accumulation and mRNA expression of proliferator-activated receptor γ (PPARγ, p < 0.01), CCAAT/enhancer binding protein α (C/EBPα, p < 0.01) and fatty acid binding protein (aP2, p < 0.01). As expected, corresponding protein contents were elevated. Importantly, APS increased 2-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)Amino)-2-Deoxyglucose (2-NBDG) uptake (p < 0.01). Meanwhile, both mRNA and protein content of glucose transporter 4 (Glut4) were elevated by APS (p < 0.01). The APS treatment enhanced tyrosine phosphorylation of insulin receptor substrate 1 (IRS1, p < 0.05) and phosphor-Akt content (p < 0.01). Besides, phosphorylated AMP-activated protein kinase (AMPK) content was increased in the APS treated cells (p < 0.01). Taken together, APS improved insulin sensitivity by enhancing glucose uptake, possibly through AMPK activation. These results suggested that APS might be a therapeutic candidate for insulin resistance.

Enhanced digestive enzyme activity and anti-adipogenic of fermented soy-powder milk with probiotic Lactobacillus plantarum P1201 through an increase in conjugated linoleic acid and isoflavone aglycone content

This study aimed to produce fermented soy-powder milk (FSPM) with Lactobacillus plantarum P1201 and to evaluate its anti-obesity activity. Isoflavone and conjugated linoleic acid (CLA) of unfermented soy-powder milk (UFSPM) and FSPM and were analyzed via high-pressure liquid chromatography (HPLC) and gas chromatography (GC). Their inhibitory activities against α-glucosidase, α-amylase, and pancreatic lipase were assayed. Their anti-obesity activities were evaluated on the basis of their inhibitory effects on adipocyte differentiation in 3T3-L1 cells, and the expression of mRNAs associated with adipogenesis and lipid metabolism were analyzed via real time-polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR). FSPM with L. plantarum P1201 increased the isoflavone aglycones (daidzein, glycitein, and genistein) content and produced CLA in soy-powder milk (SPM), both of which possessed bio-activity. Both UFSPM and FSPM showed dose-dependent inhibitory activity for α-glucosidase, α-amylase, and pancreatic lipase. FSPM, but not UFSPM, suppressed adipogenesis in 3T3-L1 cells and reduced their triglyceride content by 23.1% after treatment with 1,000 μg/mL of FSPM, compared with the control group. The anti-obesity effect of FSPM can be attributed to CLA and isoflavone aglycones, which targeted CCAAT/enhancer binding protein α (C/EBP-α) and down-regulated lipoprotein lipase (LPL), adiponectin, adipocyte fatty acid-binding protein (aP2), fatty acid synthase (FAS), and acetyl CoA carboxylase (ACC) mRNA. Furthermore, FSPM enhanced the inhibitory activity of glucosidase and pancreatic enzymes and anti-obesity activity. Further studies are required to investigate whether the anti-obesity effect of FSPM persists in an in vivo mouse model of diet-induced obesity.

Cissus quadrangularis extract (CQR-300) inhibits lipid accumulation by downregulating adipogenesis and lipogenesis in 3T3-L1 cells.

The objective of this study was to evaluate the anti-obesity activity and the action mechanism of Cissus quadrangularis extracts (CQR-300) in 3T3-L1 adipocytes. Cissus quadrangularis was extracted with hot water, resulting in CQR-300. The anti-obesity activity of CQR-300 in 3T3-L1 adipocytes was examined by Oil-red O staining. Possible mechanisms of CQR-300 in 3T3-L1 adipocytes were determined by real-time PCR and western blot. Treatment with CQR-300 inhibited lipid accumulation without showing cytotoxicity to 3T3-L1 adipocytes. Furthermore, CQR-300 decreased adipogenesis/lipogenesis-related mRNA expression levels of fatty acid binding protein (aP2), fatty acid synthase (FAS), lipoprotein lipase (LPL), stearoyl-CoA desaturase-1 (SCD-1), and acetyl-CoA carboxylase (ACC). CQR-300 also down-regulated expression levels of adipogenesis/lipogenesis-associated proteins, including peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), sterol regulatory element binding protein-1c (SREBP-1c), and FAS. It's also up-regulated the expression level of phosphorylated-AMPK (p-AMPK). Collectively, these results suggested that CQR-300 might have an anti-obesity effect by its ability to decrease expression levels of adipogenesis/lipogenesis-related genes and proteins.

Bergamottin Inhibits Adipogenesis in 3T3-L1 Cells and Weight Regulation in Diet-Induced Obese Mice.

Obesity is a serious and increasing health problem worldwide, and the inhibition of adipogenesis is considered to be a potential therapeutic target for it. Bergamottin (BGM), a component of grapefruit juice, has been reported to regulate lipolysis. However, the physiological role of BGM in obesity has not been evaluated so far. In the present study, we investigated the effects of BGM on obesity in 3T3-L1 cells and in mice fed a high-fat diet (HFD). BGM inhibited adipogenic differentiation of 3T3-L1 cells along with a significant decrease in the lipid content by downregulating the expression of two critical adipogenic factors, CCAAT enhancer-binding protein-alpha (C/EBP[Formula: see text]) and peroxisome proliferator activated receptor-gamma (PPAR[Formula: see text]). The expressions of target proteins such as adipocyte fatty acid-binding protein (aP2), adiponectin, and resistin were also decreased by BGM. It activated AMP-activated protein kinase (AMPK) by increasing phosphorylation of AMPK and the downstream target acetyl-CoA carboxylase (ACC), indicating that BGM exerted its antiadipogenic effect through AMPK activation. In the HFD-induced obese mouse model, BGM administration significantly reduced the weight and sizes of white adipose tissue as well as the weight gain of mice fed HFD. Moreover, UCP1 and PGC1[Formula: see text] expressions, well-known as brown adipocyte marker genes, were higher in the BGM-treated HFD mice than that in the HFD-induced obese mice. This study suggests that BGM suppress adipogenesis by AMPK activation in vitro and reduces body weight in vivo.

Monascus ruber-Fermented Buckwheat (Red Yeast Buckwheat) Suppresses Adipogenesis in 3T3-L1 Cells.

Although various treatments have been used for weight loss to date, obese people rarely have safe and effective treatment options. Therefore, the antiobesity effects of several natural compounds are being actively investigated. This study was conducted to investigate the antiadipogenic effects of Monascus ruber-fermented Fagopyrum esculentum (red yeast buckwheat, RYB) in 3T3-L1 cells. We assessed the intracellular lipid content and adipocyte differentiation by oil red O staining and the expression of genes and proteins associated with adipocyte differentiation by reverse transcription-polymerase chain reaction and western blotting in 3T3-L1 cells. RYB dose dependently inhibited 3T3-L1 cell differentiation at concentrations of 50-800 μg/mL, without cytotoxic effects. It also suppressed the expression of adipogenic transcription factors, including peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding protein α, and adipocyte-specific genes, such as adipocyte fatty acid-binding protein (aP2), fatty acid synthase, and leptin, during preadipocyte differentiation into adipocytes. Furthermore, RYB reduced cyclin-dependent kinase 2 and cyclin expression and increased p21 and p27 expression, thus causing cell cycle arrest at the G1/S phase. Collectively, these results suggest that RYB may be an effective nutraceutical for weight loss as indicated by its ability to suppress adipogenesis-specific gene expression and cause cell cycle arrest at the G1/S interphase.

3T3-L1 세포에서 상엽이 유발하는 AMPK signaling pathway를 통한 adipogenesis 억제에 관한 연구

상엽은 뽕나무 잎을 건조한 약재로서 항염증, 항당뇨, 미백, 항산화, 항박테리아, 항알러지 및 면역조절 등과 같은 여러 가지 약리작용을 하는 것으로 알려져 있으나 항비만 효능에 대한 연구는 부족한 실정이다. 본 연구에서는 상엽 에탄올 추출물(ethanol extracts of Mori Folium, EEMF)이 유발하는 항비만 효능을 확인하기 위하여 3T3-L1 지방전구세포가 지방세포로 분화되는 과정에서 EEMF가 어떠한 영향을 미치는 지를 조사하였다. 3T3-L1 지방전구세포의 분화유도 시 EEMF를 처리하였을 경우 지방세포의 특징인 지방방울의 수 및 지방함량이 농도의 존적으로 감소하였으며, triglyceride의 생성도 억제되는 것으로 나타났다. 또한 EEMF는 pro-adipogenic transcription factors인 SREBP-1c, <TEX>$PPAR{\gamma}$</TEX>, <TEX>$C/EBP{\alpha}$</TEX> 및 <TEX>$C/EBP{\beta}$</TEX> 의 발현억제와 함께 adipocyte-specific genes인 aP2 및 Leptin의 발현억제도 유발하는 것으로 조사되었다. 특히 EEMF는 AMPK 및 ACC의 인산화를 억제하는 것으로 나타났지만 AMPK 억제제인 compound C를 이용하여 AMPK의 활성을 억제하였을 경우 EEMF에 의하여 유발되는 pro-adipogenic transcription factors 및 adipocyte-specific genes의 억제현상이 회복되었다. 이상의 결과에서 EEMF가 유발하는 adipogenesis의 억제는 AMPK signaling pathway의 활성화를 통하여 유발된다는 것을 알 수 있었으며, 추가적인 연구를 통하여 상엽에 함유되어 있는 유효성분에 대한 분석이 필요할 것으로 생각된다. Mori Folium, the leaf of Morus alba, is a traditional medicinal herb that shows various pharmacological activities such as antiinflammatory, antidiabetic, antimelanogenesis, antioxidant, antibacterial, antiallergic, and immunomodulatory activities. However, the mechanisms of their inhibitory effects on adipocyte differentiation and adipogenesis remain poorly understood. In the present study, we investigated the inhibition of adipocyte differentiation and adipogenesis by ethanol extracts of Mori Folium (EEMF) in 3T3-L1 preadipocytes. Treatment with EEMF suppressed the terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by a decrease in the lipid droplet number and lipid content through Oil Red O staining. EEMF significantly reduced the accumulation of cellular triglyceride, which is associated with a significant inhibition of pro-adipogenic transcription factors, including sterol regulatory element-binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor-<TEX>${\gamma}$</TEX> (<TEX>$PPAR{\gamma}$</TEX>), and CCAAT/enhancer-binding proteins <TEX>${\alpha}$</TEX> (<TEX>$C/EBP{\alpha}$</TEX>) and <TEX>${\beta}$</TEX> (<TEX>$C/EBP{\beta}$</TEX>). In addition, EEMF potentially downregulated the expression of adipocyte-specific genes, including adipocyte fatty acid binding protein (aP2) and leptin. Furthermore, EEMF treatment effectively increased the phosphorylation of the AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase (ACC); however, treatment with a potent inhibitor of AMPK, compound C, significantly restored the EEMF-induced inhibition of pro-adipogenic transcription factors and adipocyte-specific genes. These results together indicate that EEMF has preeminent effects on the inhibition of adipogenesis through the AMPK signaling pathway, and further studies will be needed to identify the active compounds in Mori Folium.