4-Hydroxyderricin and xanthoangelol from Ashitaba (Angelica keiskei) suppress differentiation of preadiopocytes to adipocytes via AMPK and MAPK pathways

Traditional Chinese medicine and plant-derived natural products in regulating triglyceride metabolism: Mechanisms and therapeutic potential

The incidence of cardiometabolic disease is increasing globally, with a trend toward younger age of onset. Among these, atherosclerotic cardiovascular disease is a leading cause of mortality worldwide. Despite the efficacy of traditional lipid-lowering drugs, such as statins, in reducing low-density lipoprotein cholesterol levels, a significant residual risk of cardiovascular events remains, which is closely related to unmet triglyceride (TG) targets. The clinical application of current TG-lowering Western medicines has certain limitations, necessitating alternative or complementary therapeutic strategies. Traditional Chinese medicine (TCM) and plant-derived natural products, known for their safety owing to their natural origins and diverse biological activities, offer promising avenues for TG regulation with potentially fewer side effects. This review systematically summarises the mechanisms of TG metabolism and subsequently reviews the regulatory effects of TCM and plant-derived natural products on TG metabolism, including the inhibition of TG synthesis (via endogenous and exogenous pathways), promotion of TG catabolism, regulation of fatty acid absorption and transport, enhancement of lipophagy, modulation of the gut microbiota, and other mechanisms. In conclusion, through a comprehensive analysis of recent studies, this review consolidates the multifaceted regulatory roles of TCM and plant-derived natural products in TG metabolism and elucidates their potential as safer, multi-target therapeutic agents in managing hypertriglyceridemia and mitigating cardiovascular risk, thereby providing a basis for new drug development.

Pharmacophore Modeling and Binding Affinity of Secondary Metabolites from Angelica keiskei to HMG Co-A Reductase

Statins are cholesterol-lowering drugs with a mechanism of inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase, but long-term use can cause side effects. An example of a plant capable of reducing cholesterol levels is Angelica keiskei (ashitaba). Therefore, this study aimed to obtain suitable compounds with inhibitory activity against the HMG-CoA reductase enzyme from ashitaba through in silico tests. The experiment began with screening and pharmacophore modeling, followed by molecular docking on ashitaba's compounds, statins groups, and the native ligand was (3R,5R)-7-[4-(benzyl carbamoyl)-2-(4-fluorophenyl)-5-(1-methylethyl)-1H-imidazole-1-yl]-3,5-dihydroxyheptanoic acid (4HI). Based on the results of the molecular docking simulations, 15 hit compounds had a small binding energy (ΔG). Pitavastatin, as the comparator drug (ΔG = -8.24 kcal/mol; Ki = 2.11 µM), had a lower ΔG and inhibition constant (Ki) than the native ligand 4HI (ΔG = -7.84 kcal/mol; Ki = 7.96µM). From ashitaba's compounds, it was found that 4'-O-geranylnaringenin, luteolin, isobavachalcone, dorsmannin A, and 3'-carboxymethyl-4,2'-dihydroxy-4'-methoxychalcone have low ΔG of below -6 kcal/mol. The lowest ΔG value was found in 3'-carboxymethyl-4,2'-dihydroxy-4'-methoxy chalcone with a ΔG of -6.67 kcal/mol and Ki value of 16.66 µM, which was lower than the ΔG value of the other comparator drugs, atorvastatin (ΔG = -5.49 kcal/mol; Ki = 1148.17 µM) and simvastatin (ΔG = -6.50 kcal/mol; Ki = 22.34 µM). This compound also binds to the important amino acid residues, including ASN755D, ASP690C, GLU559D, LYS735D, LYS691C, and SER684C, through hydrogen bonds. Based on the results, the compound effectively binds to six important amino acids with good binding affinity and only requires a small concentration to reduce half of the enzyme activity.

Two Prenylated Chalcones, 4-Hydroxyderricin, and Xanthoangelol Prevent Postprandial Hyperglycemia by Promoting GLUT4 Translocation via the LKB1/AMPK Signaling Pathway in Skeletal Muscle Cells

SCOPE

Stimulation of glucose uptake in the skeletal muscle is crucial for the prevention of postprandial hyperglycemia. Insulin and certain polyphenols enhance glucose uptake through the translocation of glucose transporter 4 (GLUT4) in the skeletal muscle. The previous study reports that prenylated chalcones, 4-hydroxyderricin (4-HD), and xanthoangelol (XAG) promote glucose uptake and GLUT4 translocation in L6 myotubes, but their underlying molecular mechanism remains unclear. This study investigates the mechanism in L6 myotubes and confirms antihyperglycemia by 4-HD and XAG.

METHODS AND RESULTS

In L6 myotubes, 4-HD and XAG promote glucose uptake and GLUT4 translocation through the activation of adenosine monophosphate-activated protein kinase (AMPK) and liver kinase B1 (LKB1) signaling pathway without activating phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) and Janus kinases (JAKs)/signal transducers and activators of transcriptions (STATs) pathways. Moreover, Compound C, an AMPK-specific inhibitor, as well as siRNA targeting AMPK and LKB1 completely canceled 4-HD and XAG-increased glucose uptake. Consistently, oral administration of 4-HD and XAG to male ICR mice suppresses acute hyperglycemia in an oral glucose tolerance test.

CONCLUSION

In conclusion, LKB1/AMPK pathway and subsequent GLUT4 translocation in skeletal muscle cells are involved in Ashitaba chalcone-suppressed acute hyperglycemia.

Natural Chalcones for the Management of Obesity Disease

In the last decade, the incidence of obesity has increased dramatically worldwide, reaching a dangerous pandemic spread. This condition has serious public health implications as it significantly increases the risk of chronic diseases such as type 2 diabetes, fatty liver, hypertension, heart attack, and stroke. The treatment of obesity is therefore the greatest health challenge of our time. Conventional therapeutic treatment of obesity is based on the use of various synthetic molecules belonging to the class of appetite suppressants, lipase inhibitors, hormones, metabolic regulators, and inhibitors of intestinal peptide receptors. The long-term use of these molecules is generally limited by various side effects and tolerance. For this reason, the search for natural alternatives to treat obesity is a current research goal. This review therefore examined the anti-obesity potential of natural chalcones based on available evidence from in vitro and animal studies. In particular, the results of the main in vitro studies describing the principal molecular therapeutic targets and the mechanism of action of the different chalcones investigated were described. In addition, the results of the most relevant animal studies were reported. Undoubtedly, future clinical studies are urgently needed to confirm and validate the potential of natural chalcones in the clinical prophylaxis of obesity.

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.

Anti-obesity effect of Angelica keiskei Jiaosu prepared by yeast fermentation on high-fat diet-fed mice

In this study, an Angelica keiskei (A. keiskei) Jiaosu (FAK) was prepared by yeast fermentation to investigate its anti-obesity effect on high-fat diet (HFD)-fed mice. 70 SPF grade male C57BL/6J mice were randomly divided into 7 groups (n = 10): blank control group (N), high-fat model group (M), positive control group (Orl), unfermented control group (NF), high-dose intervention group (FH), medium-dose intervention group (FM), and low-dose intervention group (FL). The results showed that FAK intervention significantly reduced the body weight, Lee's index and liver index of HFD-fed mice (P < 0.05). Compared with M group, the serum levels of triglyceride (TG), total cholesterol (TC), leptin and glucose (GLU) in FH group were remarkably decreased and that of interleukin-27 (IL-27) were increased (P < 0.05). The levels of TG, and TC in the liver of mice were also markedly decreased in the FH group (P < 0.05). HE staining results showed that the liver cells in the three intervention groups had less degeneration and fatty vacuoles in the cytoplasm, and the liver cords were orderly arranged compared with that of M group. Furthermore, FAK significantly inhibited epididymal adipose tissue cell expansion induced by HFD. FAK up-regulated the protein expression levels of p-AMPK and PPARα to promote lipolysis and down-regulated the expression of PPARγ to reduce lipid synthesis (P < 0.05). Additionally, the results of gut microbiota showed that after the intervention, a decrease trend of F/B value and Deferribacterota was noticed in the FH group compared with M group. At the genus level, FAK intervention significantly increased that of Ileiobacterium compared to the M group (p < 0.05). A rising trend of norank_f_Muribaculaceae, Lactobacillus, and Bifidobacterium were also observed in the HF group. Conclusively, these findings demonstrated that FAK intervention can effectively improve obesity in mice caused by HFD and the potential mechanisms was related to the regulation of serum levels of leptin and IL-27, lipogenesis and lipolysis in adipose tissue and gut microbiota composition.

Novel Bacillus ginsengihumi CMRO6 Inhibits Adipogenesis via p38MAPK/Erk44/42 and Stimulates Glucose Uptake in 3T3-L1 Pre-Adipocytes through Akt/AS160 Signaling

The health benefits of probiotics have been known for decades, but there has only been limited use of probiotics in the treatment of obesity. In this study, we describe, for the first time, the role of cell-free metabolites (CM) from Bacillus ginsengihumi-RO6 (CMRO6) in adipogenesis and lipogenesis in 3T3-L1 pre-adipocytes. The experimental results show that CMRO6 treatment effectively reduced lipid droplet accumulation and the expression of CCAAT/enhancer-binding protein α and β (C/EBPα and C/EBPβ), peroxisome proliferator-activated receptor γ (PPAR-γ), serum regulatory binding protein 1c (SREBP-1c), fatty acid-binding protein 4 (FABP4), fatty acid synthase (FAS), acetyl CoA carboxylase (ACC), phosphorylated p38MAPK, and Erk44/42. Additionally, CMRO6 treatment significantly increased glucose uptake and phosphorylated Akt (S473), AS160, and TBC1D1 protein expressions. Considering the results of this study, B. ginsengihumi may be a novel probiotic used for the treatment of obesity and its associated metabolic disorders.

mTOR and ERK1/2 signaling participate in the process of acetate regulating lipid metabolism and HSL expression

Objective

Acetate plays an important role in host lipid metabolism. However, the network of acetate-regulated lipid metabolism remains unclear. Previous studies show that mitogen-activated protein kinases (MAPKs) and mechanistic target of rapamycin (mTOR) play a crucial role in lipid metabolism. We hypothesize that acetate could affect MAPKs and/or mTOR signaling and then regulate lipid metabolism. The present study investigated whether any cross talk occurs among MAPKs, mTOR and acetate in regulating lipid metabolism.

Methods

The ceramide C6 (an extracellular signaling-regulated kinases 1 and 2 [ERK1/2] activator) and MHY1485 (a mTOR activator) were used to treat rabbit adipose-derived stem cells (ADSCs) with or without acetate, respectively.

Results

It indicated that acetate (9 mM) treatment for 48 h decreased the lipid deposition in rabbit ADSCs. Acetate treatment decreased significantly phosphorylated protein levels of ERK1/2 and mTOR but significantly increased mRNA level of hormone-sensitive lipase (HSL). Acetate treatment did not significantly alter the phosphorylated protein level of p38 MAPK and c-Jun aminoterminal kinase (JNK). Activation of ERK1/2 and mTOR by respective addition in media with ceramide C6 and MHY1485 significantly attenuated decreased lipid deposition and increased HSL expression caused by acetate.

Conclusion

Our results suggest that ERK1/2 and mTOR signaling pathways are associated with acetate regulated HSL gene expression and lipid deposition.

4-Hydroxyderricin Promotes Apoptosis and Cell Cycle Arrest through Regulating PI3K/AKT/mTOR Pathway in Hepatocellular Cells

4-hydroxyderricin (4-HD), as a natural flavonoid compound derived from Angelica keiskei, has largely unknown inhibition and mechanisms on liver cancer. Herein, we investigated the inhibitory effects of 4-HD on hepatocellular carcinoma (HCC) cells and clarified the potential mechanisms by exploring apoptosis and cell cycle arrest mediated via the PI3K/AKT/mTOR signaling pathway. Our results show that 4-HD treatment dramatically decreased the survival rate and activities of HepG2 and Huh7 cells. The protein expressions of apoptosis-related genes significantly increased, while those related to the cell cycle were decreased by 4-HD. 4-HD also down-regulated PI3K, p-PI3K, p-AKT, and p-mTOR protein expression. Moreover, PI3K inhibitor (LY294002) enhanced the promoting effect of 4-HD on apoptosis and cell cycle arrest in HCC cells. Consequently, we demonstrate that 4-HD can suppress the proliferation of HCC cells by promoting the PI3K/AKT/mTOR signaling pathway mediated apoptosis and cell cycle arrest.

A novel peptide promotes human trophoblast proliferation and migration through PI3K/Akt/mTOR signaling pathway

Background

Preeclampsia (PE) is a complex pregnancy-related disease that endangers the safety of maternal and fetal. The purpose of this study is to reveal the pathogenesis of preeclampsia and discover new predictors from the perspective of peptidomics. The umbilical cord blood of PE and control group was analyzed by peptidomics. A peptide named Regulation of Proliferation Process in Preeclampsia (ROPPIP) was screened out to explore its role in the proliferation, migration and apoptosis of trophoblast cells in preeclampsia.

Methods

We compared and analyzed the umbilical cord blood of patients with PE and normal pregnant women using liquid chromatography-tandem mass spectrometry (LC-MS). hTR-8/Svneo cells cultured in vitro were divided into ROPPIP group and a disordered peptide group as control. Cell Counting Kit-8 (CCK-8) assay, flow cytometry, Transwell chamber assays and western blot analysis were performed to detect cell proliferation, invasion, migration and apoptosis, in addition to the expression of Matrix metalloproteinase-2 (MMP2), nuclear associated antigen Ki67, B-cell lymphoma-2 (Bcl2), Caspase 3, and β-actin protein.

Results

We identified 133 differential peptides. Of these, 51 were up-regulated while 82 were down-regulated. the polypeptide SFGVRMATASPTDGNV with low differential expression in the serum of PE patients was selected for the study, we named the polypeptide as Regulation of Proliferation Process in PE (ROPPIP). The experiment shows that ROPPIP can up-regulate the expression levels of MMP2, Ki67, and Bcl2 in HTR-8/Svneo cells, down-regulate the expression of caspase-3, promote the proliferation and migration of HTR-8/Svneo cells and inhibit the apoptosis induced by cisplatin, the activation of the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway may be associated with the function of ROPPIP.

Conclusions

ROPPIP promotes HTR-8/Svneo cells migration and proliferation, and inhibits apoptosis, by regulating the activation of the PI3K/AKT/mTOR signaling pathway.

Acetate stimulates lipogenesis via AMPKα signaling in rabbit adipose-derived stem cells

Acetate plays an important role in host lipid metabolism. However, the regulatory network underlying acetate-regulated lipometabolism remains unclear. The aim of this study was to determine whether any cross talk occurs among adenosine 5'-monophosphate-activated protein kinase (AMPK), mitogen-activated protein kinases (MAPKs) and acetate in regulating lipid metabolism. The compound C (an AMPK inhibitor), and SB203580 (a p38 MAPK inhibitor) were used to treat rabbit adipose-derived stem cells (ADSCs) with or without acetate, respectively. It indicated that acetate (6 mM) for 6 h increased the lipid deposition in rabbit ADSCs. Besides, acetate treatment (6 mM) increased significantly phosphorylated protein level of AMPKα and p38 MAPK, but not altered significantly the phosphorylated protein level of extracellular signaling-regulated kinase (ERK) and c-Jun aminoterminal kinase (JNK). The blocking of AMPKα signaling attenuated acetate-induced lipid accumulation, but not that of p38 MAPK signaling. In conclusion, our findings suggest that AMPKα signaling pathway is associated with acetate-induced lipogenesis.

Metabolic and transcriptome responses of RNAi-mediated AMPKα knockdown in Tribolium castaneum

Background

The AMP-activated protein kinase (AMPK) is an intracellular fuel sensor for lipid and glucose metabolism. In addition to the short-term regulation of metabolic enzymes by phosphorylation, AMPK may also exert long-term effects on the transcription of downstream genes through the regulation of transcription factors and coactivators. In this study, RNA interference (RNAi) was conducted to investigate the effects of knockdown of TcAMPKα on lipid and carbohydrate metabolism in the red flour beetle, Tribolium castaneum, and the transcriptome profiles of dsTcAMPKα-injected and dsEGFP-injected beetles under normal conditions were compared by RNA-sequencing.

Results

RNAi-mediated suppression of TcAMPKα increased whole-body triglyceride (TG) level and the ratio between glucose and trehalose, as was confirmed by in vivo treatment with the AMPK-activating compound, 5-Aminoimidazole-4-carboxamide1-β-D-ribofuranoside (AICAR). A total of 1184 differentially expressed genes (DEGs) were identified between dsTcAMPKα-injected and dsEGFP-injected beetles. These include genes involved in lipid and carbohydrate metabolism as well as insulin/insulin-like growth factor signaling (IIS). Real-time quantitative polymerase chain reaction analysis confirmed the differential expression of selected genes. Interestingly, metabolism-related transcription factors such as sterol regulatory element-binding protein 1 (SREBP1) and carbohydrate response element-binding protein (ChREBP) were also significantly upregulated in dsTcAMPKα-injected beetles.

Conclusions

AMPK plays a critical role in the regulation of beetle metabolism. The findings of DEGs involved in lipid and carbohydrate metabolism provide valuable insight into the role of AMPK signaling in the transcriptional regulation of insect metabolism.

Sinensol-C Isolated from Spiranthes sinensis Inhibits Adipogenesis in 3T3-L1 Cells through the Regulation of Adipogenic Transcription Factors and AMPK Activation

Obesity is an abnormal medical condition caused by accumulation of body fat that presents negative health impacts. Adipocyte hyperplasia, also known as adipogenesis, is one of the major manifestations of obesity. In the present study, we isolated six phenanthrene derivatives (compounds 1–6) from the ethyl acetate fraction of Spiranthes sinensis and investigated their anti-adipogenic activity. We found that among the six phenanthrene derivatives, compound 6 (sinensol-C) exhibited strong inhibitory activity against intracellular lipid accumulation in 3T3-L1 adipocytes, with an IC₅₀ value of 12.67 μM. Sinensol-C remarkably suppressed the accumulation of lipid droplets and adipogenesis, via down-regulation of adipogenic transcription factors, including peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), sterol regulatory element binding protein-1 (SREBP-1c), fatty acid synthase (FAS), and fatty acid binding protein 4 (FABP4), during adipocyte differentiation in 3T3-L1 cells. In addition, treatment with sinensol-C significantly increased the adenosine monophosphate-activated protein kinase (AMPK) activity in 3T3-L1 cells. Taken together, these data strongly suggest that sinensol-C regulates adiogenesis via down-regulation of adipogenic transcription factors and up-regulation of AMPK. Furthermore, this is the first study that demonstrates that sinensol-C has the capacity to modulate adipogenesis.

4-Hydroxyderricin and xanthoangelol isolated from Angelica keiskei prevent dexamethasone-induced muscle loss

Since a decrease in muscle mass leads to an increased risk of mortality, the prevention of muscle wasting contributes to maintaining the quality of life. Recently, we reported that glabridin, a prenylated flavonoid in licorice, prevents dexamethasone-induced muscle loss. In this study, we focused on the other prenylated chalcones 4-hydroxyderricin and xanthoangelol in Ashitaba (Angelica keiskei) and investigated their prevention effect on dexamethasone-induced muscle loss. It was found that 4-hydroxyderricin and xanthoangelol significantly prevented dexamethasone-induced protein degradation in C2C12 myotubes by suppressing the expression of ubiquitin ligases, Cbl-b and MuRF-1. These prenylated chalcones acted as the antagonists of the glucocorticoid receptor and inhibited the binding of dexamethasone to this receptor and its subsequent nuclear translocation. In addition, the chalcones suppressed the phosphorylation of p38 and FoxO3a as the upstream factors for ubiquitin ligases. Dexamethasone-induced protein degradation and upregulation of Cbl-b were attenuated by the knockdown of the glucocorticoid receptor but not by the knockdown of p38. In male C57BL/6J mice, the Ashitaba extract, containing 4-hydroxyderricin and xanthoangelol, suppressed dexamethasone-induced muscle mass wasting accompanied by a decrease in the expression of ubiquitin ligases by inhibiting the nuclear translocation of the glucocorticoid receptor and phosphorylation of FoxO3a. In conclusion, 4-hydroxyderricin and xanthoangelol are effective compounds to inhibit steroid-induced muscle loss.

Effect of Supplementation with Hydroethanolic Extract of Campomanesia xanthocarpa (Berg.) Leaves and Two Isolated Substances from the Extract on Metabolic Parameters of Mice Fed a High-Fat Diet

There are still controversies regarding the correlation between the beneficial effects for health and the administration of isolated compounds or crude extracts in therapeutic applications. Campomanesia xanthocarpa, found in the Brazilian Cerrado, demonstrated beneficial effects in metabolic disorders associated with obesity. We investigated the effects of Campomanesia xanthocarpa hydroethanolic extract and two isolated substances from the extract (S1 and S2) in a diet-induced obesity (DIO) model. Male Swiss mice were divided into five groups: (1) American Institute of Nutrition (AIN-93M) diet, (2) high-fat diet (HF), (3) HF supplemented with C. xanthocarpa hydroethanolic leaf extract at 100 mg/kg (HFE), (4) HF supplemented with S1 at 1 mg/kg (HFS1) and (5) HF supplemented with S2 at 1 mg/kg (HFS2). The HFS1, HFS2 and HFE groups did not present decreasing body weight or visceral adiposity gain. No differences in glycemic and lipid parameters, or in the expression of protein content in two cytokines, interleukin-6 (IL-6) and anti-inflammatory (IL-10), were observed. Only the HFS1 group displayed decreased food intake. Even though substantial effects such as an improvement in obesity features or the metabolic and histological parameters promoted by S1, S2 and the extract were not observed, further investigations are necessary to evaluate the principal genes and protein expressions involved in regulating food behavior promoted by S1.

A Chalcone from Ashitaba (Angelica keiskei) Stimulates Myoblast Differentiation and Inhibits Dexamethasone-Induced Muscle Atrophy

Ashitaba, Angelica keiskei Koidzumi (AK), as a traditional medicine in Korea, Japan, and China, has been known as an elixir of life having therapeutic potential. However, there is no scientific evidence to support that Ashitaba can enhance or maintain muscle strength. To find a new therapeutic agent from the medicinal plant, we evaluated the anti-myopathy effect of chalcones from ethanol extract of AK (EAK) in cellular and animal models of muscle atrophy. To examine anti-myopathy activity, EAK was treated into dexamethasone injected rats and muscle thickness and histopathological images were analyzed. Oral administration of EAK (250 or 500 mg/kg) alleviated muscle atrophic damages and down-regulated the mRNA levels of muscle-specific ubiquitin-E3 ligases. Among ten compounds isolated from EAK, 4-hydroxyderricin was the most effective principle in stimulating myogenesis of C2C12 myoblasts via activation of p38 mitogen-activated protein kinase (MAPK). In three cellular muscle atrophy models with C2C12 myoblasts damaged by dexamethasone or cancer cell-conditioned medium, 4-hydroxyderricin protected the myosin heavy chain (MHC) degradation through suppressing expressions of MAFbx, MuRF-1 and myostatin. These results suggest that the ethanol extract and its active principle, 4-hydroxyderricin from AK, can overcome the muscle atrophy through double mechanisms of decreasing muscle protein degradation and activating myoblast differentiation.

Penta-O-galloyl-β-d-glucose, a hydrolysable tannin from Radix Paeoniae Alba, inhibits adipogenesis and TNF-α-mediated inflammation in 3T3-L1 cells

Penta-O-galloyl-β-d-glucose (PGG) was purified and identified from Radix Paeoniae Alba by HSCCC and HPLC/ESI-MS, and its inhibitory effects on adipogenesis and TNF-α-induced inflammation were assessed in 3T3-L1 cell line. The results showed that PGG dose-dependently reduced intracellular lipids accumulation, and this involved decrease the expression levels of major adipogenic markers, PPARγ, C/EBP α, through MAPKs inhibition. This was accompanied by a reduction of lipogenic genes, ACC, FAS, and SCD-1, involved in fatty acid synthesis. Furthermore, PGG also inhibited TNF-α-induced expression of inflammatory cytokines including IL-6 and MCP-1 in the matured 3T3-L1 adipocytes. The inhibitions were likely mediated by blocking the MAPKs and NF-κB activation. These findings highlighted that PGG could serve as a potent therapeutic agent for controlling obesity and obesity-related chronic inflammation.

Benzyl isothiocyanate ameliorates lipid accumulation in 3T3-L1 preadipocytes during adipocyte differentiation

Benzyl isothiocyanate (BITC) is an organosulfur compound derived from cruciferous vegetables and papaya seeds. In this study, we investigated the effect of BITC on the lipid accumulation in 3T3-L1 preadipocytes during adipocyte differentiation. The treatment of BITC during the differentiation-inducing stage significantly ameliorated the lipid accumulation, whereas it had no inhibitory effect during the differentiation-maintaining stage. BITC also significantly suppressed the mRNA expression of the adipocyte-specific markers, such as CCAAT/enhancer-binding protein α (C/EBPα), C/EBPβ, C/EBPδ and peroxisome proliferator-activated receptor γ. BITC significantly inhibited the phosphorylation of extracellular signal-regulated kinase phosphorylation, whereas it enhanced that of AMP-activated protein kinase. Furthermore, BITC significantly suppressed the intracellular 2-deoxyglucose uptake as well as glucose transporter 4 expression. These results suggest that inhibition of the adipocyte differentiation and glucose uptake may mainly contribute to the inhibitory effect of BITC on the lipid accumulation in 3T3-L1 preadipocytes. Abbreviations: PPARγ: peroxisome proliferator-activated receptor γ; CEBP: CCAAT/enhancer-binding protein; GLUT4: glucose transporter 4; AMPK: AMP-activated protein kinase; ERK1/2: extracellular signal-regulated kinase 1/2; MAPK: a mitogen-activated protein kinase; ITCs: isothiocyanates; BITC: benzyl isothiocyanate; FBS: fetal bovine serum; CS: calf serum; AITC: allyl ITC; IBMX: 3-isobutyl-1-methylxanthine; LDH: lactate dehydrogenase; KRH: Krebs-Ringer-Hepes-bicarbonate; 2-DG: 2-deoxy-d-glucose.

Caffeine-Stimulated Intestinal Epithelial Cells Suppress Lipid Accumulation in Adipocytes

Caffeine is a methylxanthine derived from plant foods such as coffee beans and tea leaves, and has multiple biological activities against physiological response and several diseases. Although there are some reports about the direct effect of caffeine against anti-lipid accumulation in vitro, the effect of caffeine on lipid accumulation in adipocytes through stimulating intestinal epithelial cells is unknown. Since direct treatment with caffeine to 3T3-L1 cells did not affect lipid accumulation, we determined whether caffeine-stimulated intestinal epithelial Caco-2 cells influence the lipid accumulation in 3T3-L1 adipocytes. Caco-2 cells were cultured on a transwell insert with or without caffeine for 24 h. Subsequently, the basolateral component of the Caco-2 cell culture on the transwell was collected and termed caffeine-conditioning medium (CCM). When 3T3-L1 adipocytes were incubated with CCM, CCM decreased lipid accumulation and suppressed gene expression of proliferator activated receptor (PPAR) γ and CCAAT/enhancer binding protein (C/EBP) α in 3T3-L1 adipocytes. Furthermore, CCM decreased the expression of C/EBPβ and C/EBPδ at the protein level, but not at the mRNA level. We observed that a proteasome inhibitor, MG132, inhibited CCM-caused down-expression of C/EBPβ and C/EBPδ proteins, and that CCM promoted the ubiquitination level of C/EBPβ and C/EBPδ proteins. Protein microarray analysis showed caffeine suppresses the secretion of inflammatory cytokines, interleukin-8 and plasminogen activator inhibitor-1 from Caco-2 cells. These results suggest that caffeine indirectly suppresses lipid accumulation in 3T3-L1 adipocytes through decreasing secretion of inflammatory cytokines from Caco-2 cells.

The Ashitaba (Angelica keiskei) Chalcones 4-hydroxyderricin and Xanthoangelol Suppress Melanomagenesis By Targeting BRAF and PI3K

Malignant melanoma is an aggressive tumor of the skin and still lacks effective preventive and therapeutic treatments. In melanoma, both the BRAF/MEK/ERK and PI3-K/AKT signaling pathways are constitutively activated through multiple mechanisms, which result in cell-cycle progression and prevention of apoptosis. Therefore, the development of novel strategies for targeting BRAF and PI3K are of utmost importance. In this study, we found that Ashitaba (Angelica keiskei) chalcones, 4-hydroxyderricin (4HD) and xanthoangelol (XAG), suppressed melanoma development by directly targeting both BRAFV600E and PI3K, which blocked the activation of downstream signaling. This led to the induction of G₁ phase cell-cycle arrest and apoptosis in melanoma cells. Importantly, 4HD or XAG dramatically attenuated tumor incidence and volume in the BRAF-activated Pten-deficient melanoma mouse model. Our findings suggest that 4HD and XAG are promising chemopreventive or potential therapeutic agents against melanomagenesis that act by targeting both BRAF and PI3K, providing hope for rapid clinical translation. Cancer Prev Res; 11(10); 607-20. ©2018 AACR.

Inactivation of MAPK in epididymal fat and amelioration of triglyceride secretion by injection of GRK2 siRNA in ob/ob mice

Abnormal G protein-coupled receptor kinase 2 (GRK2) accumulation has a crucial role in the development of insulin resistance and diabetes. Although GRK2 siRNA transfection in the liver improves insulin resistance-related vascular complications, the effects of GRK2 siRNA in lipid metabolism and obesity remain unknown. To investigate how GRK2 siRNA affects obesity, ob/ob mice were transfected with GRK2 siRNA, mainly in the liver, by using a hydrodynamic-based procedure. Epididymal fat, glucose, triglyceride, non-esterified fatty acid (NEFA), and alanine transaminase activity were higher in the control siRNA-transfected ob/ob mice than in the control siRNA-transfected Lean mice, but these parameters were reduced by GRK2 siRNA transfection into the ob/ob mice. GRK2 expression in epididymal fat was not altered among the 3 groups, although hepatic GRK2 expression was higher in the control siRNA-transfected ob/ob mice than in the control siRNA-transfected Lean mice. Additionally, we found that Akt interacted with GRK2 in the liver. Furthermore, phosphorylation levels of ERK1/2 and JNK were higher in the epididymal fats from the control siRNA-transfected ob/ob mice than in those from the control siRNA-transfected Lean mice, but they were lowered by transfection with GRK2 siRNA. The study results showed that GRK2 siRNA improved blood triglyceride levels and abnormal or excessive activity of mitogen-activated protein kinases in epididymal fat. This effect may be promoted by inhibition of the NEFA production pathway in the liver. Therefore, the interaction of organs (hepatic GRK2-epididymal fat) may help improve insulin resistance and diabetes-associated pathophysiology.

Phloretin Promotes Adipogenesis via Mitogen-Activated Protein Kinase Pathways in Mouse Marrow Stromal ST2 Cells

Phloretin, a glucose transporter (GLUT) inhibitor, has pleiotropic effects. The present study examined the effects of phloretin on the commitment of marrow stromal cells to adipocytes, using the mouse marrow stromal cell line ST2. Oil red O staining showed that treatment with phloretin 10–100 µM promoted lipid accumulation. Real-time PCR showed that phloretin significantly increased the expression of adipogenic markers, including PPARγ, C/EBPα, fatty acid synthase, fatty acid-binding protein 4, and adiponectin. Western blotting showed that phloretin inhibited ERK1/2 and JNK but activated p38 MAPK. Treatment with a MAPK/ERK kinase inhibitor and a JNK inhibitor enhanced adipogenesis, similar to phloretin. In contrast, a p38 MAPK inhibitor suppressed phloretin-induced adipogenesis. Although phloretin phosphorylated AMP-activated protein kinase (AMPK), co-incubation with an AMPK inhibitor did not block phloretin-induced adipogenesis. The 2-deoxyglucose colorimetric assay showed that phloretin and siRNA silencing of GLUT1 decreased glucose uptake. However, unlike phloretin treatment, GLUT1 silencing inhibited adipogenesis. In addition, phloretin enhanced adipogenesis in GLUT1 knocked-down cells. Taken together, phloretin induced adipogenesis of marrow stromal cells by inhibiting ERK1/2 and JNK and by activating p38 MAPK. The adipogenic effects of phloretin were independent of glucose uptake inhibition. Phloretin may affect energy metabolism by influencing adipogenesis and adiponectin expression.

Isobavachalcone from Angelica keiskei Inhibits Adipogenesis and Prevents Lipid Accumulation

We isolated isobavachalcone (IBC) from Angelica keiskei (AK) as an anti-obesity component. IBC dose-dependently inhibited 3T3-L1 adipocyte differentiation by down-regulating adipogenic factors. At the mitotic clonal expansion stage (MCE), IBC caused cell cycle arrest in G0/G1 with decreased expression of cell cycle-regulating proteins. IBC also inhibited autophagic flux by inducing intracellular accumulation of LC3B and SQSTM1/p62 proteins while decreasing expression levels of regulating factors for autophagy initiation. In parallel with the inhibition of adipocyte differentiation, IBC decreased intrahepatic fat deposits and rescued the liver steatosis in high fat cholesterol diet-fed zebrafish. In this study, we found that IBC isolated from AK suppresses mitotic clonal expansion and autophagy flux of adipocytes and also shows anti-obesity activity in a high cholesterol-diet zebrafish model by decreasing intrahepatic fat deposits. These results suggest that IBC could be a leading pharmacological compound for the development of anti-obesity drugs.

Inhibitory effect of sinigrin on adipocyte differentiation in 3T3-L1 cells: Involvement of AMPK and MAPK pathways

Adipocyte differentiation is a critical adaptive response to nutritional overload and affects the metabolic outcome of obesity. Sinigrin (2-propenyl glucosinolate) is a glucosinolate belong to the glucoside contained in broccoli, brussels sprouts, and black mustard seeds. We investigated the effects of sinigrin on adipogenesis in 3T3-L1 preadipocytes and its underlying mechanisms. Sinigrin remarkably inhibited the accumulation of lipid droplets and adipogenesis by downregulating the expression of CCAAT-enhancer-binding protein α (C/EBPα), peroxisome proliferator-activated receptor gamma (PPARγ), leptin and aP2. Sinigrin arrested cells in the G₀/G₁ phase of the cell cycle and increased the expression of p21 and p27. CDK2 expression was suppressed by sinigirn in MDI-induced adipocytes. Sinigrin increased the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK) and acetyl-CoA carboxylase (ACC) in the early stage of adipocyte differentiation, suggesting that sinigrin has anti-adipogenic effects through AMPK, MAPK and ACC activation. Sinigrin also inhibited the production of pro-inflammatory cytokines including tumor necrosis factor -alpha (TNF-α) and interleukin (IL)-6, IL-1β and IL-18. Taken together, these data suggest that sinigrin inhibits early-stage adipogenesis of 3T3-L1 adipocytes through the AMPK and MAPK signaling pathways.

Milk Fat Globule Membrane Attenuates High-Fat Diet-Induced Obesity by Inhibiting Adipogenesis and Increasing Uncoupling Protein 1 Expression in White Adipose Tissue of Mice

Milk fat globule membrane (MFGM), a protein-lipid complex surrounding the fat globules in milk, has many health benefits. The aim of the current study was to investigate whether MFGM could prevent obesity through inhibiting adipogenesis and promoting brown remodeling of white adipose tissue (WAT) in mice fed with high-fat diet. C57BL/6 mice were fed a normal diet (ND), high-fat diet (HFD), HFD plus MFGM at 100 mg/kg BW, 200 mg/kg BW or 400 mg/kg BW for 8 weeks. Results showed that MFGM suppressed body weight gain induced by HFD, reduced white adipose tissue (WAT) mass accompanied with the decrease in adipocyte sizes. MFGM was found to have partially improved serum lipid profiles, as well as to have suppressed HFD-induced adipogenesis as shown by reduced expression of peroxisome proliferators-activator receptor-γ (PPARγ), CCAAT/enhancer-binding protein-α (C/EBPα) and sterol regulatory element-binding protein-1c (SREBP-1c). MFGM also markedly increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), showing activation of AMPK pathway. Moreover, MFGM promoted browning of inguinal WAT by upregulation the protein expression of uncoupling protein 1 (UCP1) in HFD mice. Taken together, these findings provide evidence that MFGM may protect against diet-induced adiposity by suppressing adipogenesis and promoting brown-like transformation in WAT.

Anti-obesity effects of pectinase and cellulase enzyme‑treated Ecklonia cava extract in high‑fat diet‑fed C57BL/6N mice

The present study investigated the anti‑obesity effects of enzyme‑treated Ecklonia cava extract (EEc) in C57BL/6N mice with high‑fat diet (HFD)‑induced obesity. The EEc was separated and purified with the digestive enzymes pectinase (Rapidase X‑Press L) and cellulase (Rohament CL) and its effects on the progression of HFD‑induced obesity were examined over 10 weeks. The mice were divided into 6 groups (n=10/group) as follows: Normal diet group, HFD group, mice fed a HFD with 25 mg/kg/day Garcinia cambogia extract and mice fed a HFD with 5, 25 or 150 mg/kg/day EEc (EHD groups). Changes in body weight, fat, serum lipid levels and lipogenic enzyme levels were determined. The body weight and liver weight were increased in the HFD group compared with those in the ND group, which was significantly reduced by EEc supplementation. In addition, significant reductions in epididymal, perirenal and mesenteric white adipose tissues were present in the EHD groups and all three EHD groups exhibited decreases in insulin, leptin and glutamate pyruvate transaminase levels compared with those in the HFD group. In addition, EEc treatment significantly decreased the serum and hepatic triglyceride levels compared with those in the HFD group. However, the levels of high‑density lipoprotein cholesterol/total cholesterol ration increased significantly in EHD‑25 and ‑150 groups compared with those in the HFD group. Changes in adipogenic and lipogenic protein expression in the liver was assessed by western blot analysis. The EHD‑25 and -150 groups exhibited reduced levels of CCAAT/enhancer‑binding protein α and peroxisome proliferator activated receptor γ. However, the phosphorylation ratios of AMP‑activated protein kinase and acetyl‑CoA carboxylase were significantly increased in the liver tissue obtained from the EHD (5, ‑25 and ‑150 mg/kg/day) groups compared with those in the HFD group. EEc supplementation reduced levels of sterol regulatory element‑binding protein‑1c, adipose fatty acid‑binding protein, fatty acid synthase and leptin, while it significantly increased glucose transporter type 4 and adiponectin protein levels in the liver tissues of all three EHD groups compared with those in the HFD group. Taken together, these results suggest that EEc exerts anti‑obesity effects by reducing body weight and the serum and hepatic levels of obesity‑associated factors. Thus, EEc supplementation reduces HFD‑induced obesity in C57BL/6N mice and has the potential to prevent obesity and subsequent metabolic disorders.

Bee Venom Suppresses the Differentiation of Preadipocytes and High Fat Diet-Induced Obesity by Inhibiting Adipogenesis

Bee venom (BV) has been widely used in the treatment of certain immune-related diseases. It has been used for pain relief and in the treatment of chronic inflammatory diseases. Despite its extensive use, there is little documented evidence to demonstrate its medicinal utility against obesity. In this study, we demonstrated the inhibitory effects of BV on adipocyte differentiation in 3T3-L1 cells and on a high fat diet (HFD)-induced obesity mouse model through the inhibition of adipogenesis. BV inhibited lipid accumulation, visualized by Oil Red O staining, without cytotoxicity in the 3T3-L1 cells. Male C57BL/6 mice were fed either a HFD or a control diet for 8 weeks, and BV (0.1 mg/kg or 1 mg/kg) or saline was injected during the last 4 weeks. BV-treated mice showed a reduced body weight gain. BV was shown to inhibit adipogenesis by downregulating the expression of the transcription factors CCAAT/enhancer-binding proteins (C/EBPs) and the peroxisome proliferator-activated receptor gamma (PPARγ), using RT-qPCR and Western blotting. BV induced the phosphorylation of AMP-activated kinase (AMPK) and acetyl-CoA carboxylase (ACC) in the cell line and in obese mice. These findings demonstrate that BV mediates anti-obesity/differentiation effects by suppressing obesity-related transcription factors.

Minor phenolics from Angelica keiskei and their proliferative effects on Hep3B cells

A new coumarin, (-)-cis-(3'R,4'R)-4'-O-angeloylkhellactone-3'-O-β-d-glucopyranoside (1) and two new chalcones, 3'-[(2E)-5-carboxy-3-methyl-2-pentenyl]-4,2',4'-trihydroxychalcone (4) and (±)-4,2',4'-trihydroxy-3'-{2-hydroxy-2-[tetrahydro-2-methyl-5-(1-methylethenyl)-2-furanyl]ethyl}chalcone (5) were isolated from the aerial parts of Angelica keiskei (Umbelliferae), together with six known compounds: (R)-O-isobutyroyllomatin (2), 3'-O-methylvaginol (3), (-)-jejuchalcone F (6), isoliquiritigenin (7), davidigenin (8), and (±)-liquiritigenin (9). The structures of the new compounds were determined by interpretation of their spectroscopic data including 1D and 2D NMR data. All known compounds (2, 3, and 6-9) were isolated as constituents of A. keiskei for the first time. To identify novel hepatocyte proliferation inducer for liver regeneration, 1-9 were evaluated for their cell proliferative effects using a Hep3B human hepatoma cell line. All isolates exhibited cell proliferative effects compared to untreated control (DMSO). Cytoprotective effects against oxidative stress induced by glucose oxidase were also examined on Hep3B cells and mouse fibroblast NIH3T3 cells and all compounds showed significant dose-dependent protection against oxidative stress.

Fucosterol inhibits adipogenesis through the activation of AMPK and Wnt/β-catenin signaling pathways

Fucosterol is a sterol constituent primarily derived from brown algae. Recently, the antiadipogenic effect of fucosterol has been reported; however, its molecular mechanism remains to be studied. Fucosterol effectively upregulated the phosphorylations of both adenosine monophosphate (AMP)-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), and downregulated the expression levels of lipogenesis-related factors. Moreover, fucosterol activated the major components of the Wnt/β-catenin signaling pathway, including β-catenin, disheveled 2 (DVL2), and cyclin D1 (CCND1), whereas it inactivated glycogen synthase kinase 3β (p-GSK3β) by stimulating its phosphorylation. In the presence or absence of fucosterol, the adipogenic transcriptional factors [peroxisome proliferator activated-receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), and sterol regulatory element binding protein-1c (SREBP-1c)] were upregulated by the inhibition of AMPK by compound C or the knockdown of β-catenin by siRNA. Overall, these data demonstrate that fucosterol prevents adipogenesis by mediating both AMPK- and Wnt/β-catenin-signaling pathways.

Angelica keiskei, an emerging medicinal herb with various bioactive constituents and biological activities

Angelica keiskei (Miq.) Koidz. (Umbelliferae) has traditionally been used to treat dysuria, dyschezia, and dysgalactia as well as to restore vitality. Recently, the aerial parts of A. keiskei have been consumed as a health food. Various flavonoids, coumarins, phenolics, acetylenes, sesquiterpene, diterpene, and triterpenes were identified as the constituents of A. keiskei. The crude extracts and pure constituents were proven to inhibit tumor growth and ameliorate inflammation, obesity, diabetics, hypertension, and ulcer. The extract also showed anti-thrombotic, anti-oxidative, anti-hyperlipidemic, anti-viral, and anti-bacterial activities. This valuable herb needs to be further studied and developed not only to treat these human diseases but also to improve human health. Currently A. keiskei is commercialized as a health food and additives in health drinks. This article presents a comprehensive review of A. keiskei and its potential place in the improvement of human health.

Piceatannol Exerts Anti-Obesity Effects in C57BL/6 Mice through Modulating Adipogenic Proteins and Gut Microbiota

Obesity is a global health concern. Piceatannol (Pic), an analog of resveratrol (Res), has many reported biological activities. In this study, we investigated the anti-obesity effect of Pic in a high-fat diet (HFD)-induced obese animal model. The results showed that Pic significantly reduced mouse body weight in a dose-dependent manner without affecting food intake. Serum total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL) levels, and blood glucose (GLU) were significantly lowered in Pic-treated groups. Pic significantly decreased the weight of liver, spleen, perigonadal and retroperitoneal fat compared with the HFD group. Pic significantly reduced the adipocyte cell size of perigonadal fat and decreased the weight of liver. Pic-treated mice showed higher phosphorylated adenosine 5′-monophosphate-activated protein kinase (pAMPK) and phosphorylated acetyl-CoA carboxylase (pACC) protein levels and decreased protein levels of CCAAT/enhancer-binding protein C/EBPα, peroxisome proliferator-activated receptor PPARγ and fatty acid synthase (FAS), resulting in decreased lipid accumulation in adipocytes and the liver. Pic altered the composition of the gut microbiota by increasing Firmicutes and Lactobacillus and decreasing Bacteroidetes compared with the HFD group. Collectively, these results suggest that Pic may be a candidate for obesity treatment.

Defatted safflower seed extract inhibits adipogenesis in 3T3-L1 preadipocytes and improves lipid profiles in C57BL/6J ob/ob mice fed a high-fat diet

In the present study, we hypothesized that defatted safflower seed which is known to be rich in polyphenols might influence adipogenesis and obesity-related disorders, and therefore the anti-adipogenic and hypolipidemic effects of ethanol extract from defatted safflower (Cathamus tinctorius L.) seeds (CSE) were investigated both in cultured 3T3-L1 preadipocytes and in C57BL/6J ob/ob mice fed a high-fat diet. CSE inhibited adipocyte differentiation of 3T3-L1 preadipocytes and decreased expression of the adipogenic transcription factors, SREBP1c and PPARγ, and their target genes. Six-week-old obese (ob/ob) mice were fed a high-fat diet and treated with CSE (50 or 100 mg/kg/day) by oral gavage for 6 weeks. Body fat mass (epididymal and perirenal white adipose tissues) in the CSE-treated groups was significantly lower than that in the high-fat diet control (HFD) group, whereas average daily food intake was not significantly different among the groups. Plasma and hepatic triglyceride levels and plasma low-density lipoprotein cholesterol level were also significantly lower in the CSE groups compared to the HFD group. These results suggest that CSE which decreases body fat mass and improves lipid profiles in plasma and liver, represents a potential treatment option for obesity and associated metabolic disorders, including hyperlipidemia.

Antitumor and antimetastatic actions of xanthoangelol and 4-hydroxyderricin isolated from Angelica keiskei roots through the inhibited activation and differentiation of M2 macrophages

BACKGROUND

Tumor growth and metastasis have been closely associated with the M2 macrophage-induced activation of tumor-associated macrophages (TAMs).

PURPOSE

The antitumor and antimetastatic actions of xanthangelol and 4-hydroxyderricin on the role of M2 macrophages in the TAMs of highly metastatic osteosarcoma LM8-bearing mice have not yet been fully elucidated. In order to clarify the mechanisms underlying the antitumor and antimetastatic actions of the above chalcones, we performed in vivo and in vitro studies.

STUDY DESIGN

The antitumor and antimetastatic actions of xanthoangelol and 4-hydroxyderricin were examined in vivo and the effects on M2 macrophage differentiation and activation were examined in vitro.

METHODS

We examined the antitumor and antimetastatic effects of xanthoangelol and 4-hydroxyderricin on highly metastatic osteosarcoma LM8-bearing mice (in vivo). Further, we examined their effects on the differentiation of interleukin (IL)-4 plus IL-13-induced M2 macrophages and activation of IL-4 plus IL13-induced M2 macrophages (in vitro). We also investigated the expression and phosphorylation of signal transducer and activator of transcript 3 (Stat 3) in the differentiation process of M2-polarized macrophages (in vitro).

RESULTS

Xanthoangelol or 4-hydroxyderricin (25 or 50 mg/kg, twice daily) inhibited tumor growth, metastasis to the lung and liver, and TAM expression in tumors. In addition, xanthoangelol (10, 25 or 50 μM) and 4-hydroxyderricin (5, 10, 25 or 50 μM) inhibited the production of IL-10 and monocyte chemoattractant protein (MCP)-1 in M2-polarized macrophages. This result indicated that xanthoangelol and 4-hydroxyderricin inhibited the activation of M2 macrophages. Furthermore, xanthoangelol (5-50 μM) inhibited the phosphorylation of Stat 3 without affecting the expression of the Stat 3 protein in the differentiation process of M2 macrophages, which indicated that these chalcones inhibited the differentiation of M2 macrophages.

CONCLUSION

These findings suggested that the antitumor and antimetastatic actions of xanthoangelol and 4-hydroxyderrcin might be attributed to the regulated activated TAMs through the inhibition of activation and differentiation of M2 macrophages in the tumor microenvironment.

A-type ECG and EGCG dimers disturb the structure of 3T3-L1 cell membrane and strongly inhibit its differentiation by targeting peroxisome proliferator-activated receptor γ with miR-27 involved mechanism

The effects of four proanthocyanidin dimers including epicatechin-(4β→8, 2β→O→7)-epicatechin (A-type EC dimer), epicatechin-(4β→8)-epicatechin (B-type EC dimer), epicatechin-3-gallate-(4β→8, 2β→O→7)-epicatechin-3-gallate (A-type ECG dimer) and epigallocatechin-3-gallate-(4β→8, 2β→O→7)-epigallocatechin-3-gallate (A-type EGCG dimer) on 3T3-L1 preadipocyte cell differentiation and the underlying mechanisms were explored and compared. The results showed that A-type ECG dimer and A-type EGCG dimer significantly reduced the intracellular lipid accumulation in 3T3-L1 preadipocyte cells by targeting miR-27a and miR-27b as well as peroxisome proliferator-activated receptor γ (PPARγ) in the early stage of differentiation, while A-type EC dimer and B-type EC dimer showed little effect. In addition, our results revealed that the inhibitory effects of proanthocyanidin dimers on 3T3-L1 preadipocyte differentiation were highly structure-dependent and the effects were associated with the dimer-membrane interactions. The presence of galloyl moieties and A-type linkage within the structure of proanthocyanidins might be crucial for their inhibitory effect on adipogenesis. The strong disturbing effects of A-type ECG and A type EGCG dimers on the fluidity, hydrophobicity and permeability of membrane of 3T3-L1 preadipocyte cell were at least, in part, responsible for their distinct inhibitory effects on adipocyte hyperplasia.

Two chalcones, 4-hydroxyderricin and xanthoangelol, stimulate GLUT4-dependent glucose uptake through the LKB1/AMP-activated protein kinase signaling pathway in 3T3-L1 adipocytes

4-Hydroxyderricin (4HD) and xanthoangelol (XAG) are major components of n-hexane/ethyl acetate (5:1) extract of the yellow-colored stem juice of Angelica keiskei. 4-Hydroxyderricin and XAG have been reported to increase glucose transporter 4 (GLUT4)-dependent glucose uptake in 3T3-L1 adipocytes, but the detailed mechanism of this phenomenon remains unknown. This present study was aimed at clarifying the detailed mechanism by which 4HD and XAG increase GLUT4-dependent glucose uptake in 3T3-L1 adipocytes. Both 4HD and XAG increased glucose uptake and GLUT4 translocation to the plasma membrane. 4-Hydroxyderricin and XAG also stimulated the phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase. In addition, phosphorylation of liver kinase B1 (LKB1), which acts upstream of AMPK, was also increased by 4HD and XAG treatment. Small interfering RNA knockdown of LKB1 attenuated 4HD- and XAG-stimulated AMPK phosphorylation and suppressed glucose uptake. These findings demonstrate that 4HD and XAG can increase GLUT4-dependent glucose uptake through the LKB1/AMPK signaling pathway in 3T3-L1 adipocytes.

Toxicological assessment of Ashitaba Chalcone

The plant Angelica keiskei contains two main physiologically active flavonoid chalcones, 4-hydroxyderricin and xanthoangelol. Known as ashitaba in Japan, powder from the sap is widely consumed for its medicinal properties in Asia as a dietary supplement. Limited previously reported mammalian studies were without evidence of toxicity. GLP studies reported here, including a bacterial reverse mutation assay, a chromosome aberration assay, and an in vivo micronucleus assay are negative for genotoxicity. A GLP- compliant 90-day repeated oral gavage study of ashitaba yellow sap powder containing 8.45% chalcones in Sprague Dawley rats resulted in expected known physiological effects on coagulation parameters and plasma lipids at 300 and 1000 mg/kg/day. Ashitaba-related pathology included a dose-related male rat-specific alpha 2-urinary globulin nephropathy at 100, 300, and 1000 mg/kg/day and jejunal lymphangiectasia in both sexes at 1000 mg/kg/day. All other study parameters and histopathological changes were incidental or not of toxicological concern. Based on these studies ashitaba chalcone powder is not genotoxic with a NOAEL of 300 mg/kg in male and female rats.

Ashitaba (Angelica keiskei) extract prevents adiposity in high-fat diet-fed C57BL/6 mice

Two main chalcones, 4-hydroxyderricin and xanthoangelol, from Ashitaba, which is a food ingredient and a folk medicine in Asia, have been demonstrated to modulate lipid metabolism in 3T3-L1 and HepG2 cells. In this study, we investigated the effects of Ashitaba extract on adiposity in mice fed a high-fat (HF) diet and its underlying mechanisms based on adipose tissue and hepatic lipid metabolism. C57BL/6 mice were fed a normal or HF diet supplemented with Ashitaba extract (0.01% and 0.1%, w/w) for 16 weeks. Ashitaba extract suppressed the HF diet-induced body weight gain and fat deposition in white adipose tissue, reduced plasma cholesterol, glucose, and insulin levels, increased the adiponectin level, lowered triglyceride and the liver cholesterol content, increased phosphorylation of AMP-activated protein kinase (AMPK) in adipose tissue and liver, inhibited lipogenesis in adipose tissue by down-expression of peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer-binding protein α and sterol regulatory element-binding protein 1 (SREBP1), inhibited lipogenesis in the liver by down-expression of SREBP1 and its target enzyme fatty acid synthase, and promoted fatty acid oxidation by up-expression of carnitine palmitoyltransferase-1A and PPARα. In conclusion, Ashitaba extract can possibly prevent adiposity through modulating lipid metabolism through phosphorylation of AMPK in adipose tissue and liver.

Dioscin inhibits adipogenesis through the AMPK/MAPK pathway in 3T3-L1 cells and modulates fat accumulation in obese mice

Dioscin (DS) is a steroidal saponin present in a number of medicinal plants and has been shown to exert anticancer, antifungal and antiviral effects. The present study aimed to deternube the effects DS on the regulation of adipogenesis and to elucidate the underlying mechanisms. In vitro experiments were performed using differentiating 3T3-L1 cells treated with various concentrations (0-4 µM) of DS for 6 days. A cell viability assay was performed on differentiating cells following exposure to DS. Oil Red O staining and triglyceride content assay were performed to evaluate the lipid accumulation in the cells. We also carried out the following experiments: i) flow cytometry for cell cycle analysis, ii) quantitative reverse transcription polymerase chain reaction for measuring adipogenesis-related gene expression, and iii) western blot analysis to measure the expression of adipogenesis transcription factors and AMP-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC) and mitogen-activated protein kinase (MAPK) phosphorylation. In vivo experiements were performed using mice with obesity induced by a high-fat diet (HFD) that were treated with or without DS for 7 weeks. DS suppressed lipid accumulation in the 3T3-L1 cells without affecting viability at a dose of up to 4 µM. It also delayed cell cycle progression 48 h after the initiation of adipogenesis. DS inhibited adipocyte differentiation by the downregulation of adipogenic transcription factors and attenuated the expression of adipogenesis-associated genes. In addition, it enhanced the phosphorylation of AMPK and its target molecule, ACC, during the differentiation of the cells. Moreover, the inhibition of adipogenesis by DS was mediated through the suppression of the phosphorylation of MAPKs, such as extracellular-regulated kinase 1/2 (ERK1/2) and p38, but not c-Jun-N-terminal kinase (JNK). DS significantly reduced weight gain in the mice with HFD-induced obesity; this was evident by the suppression of fat accumulation in the abdomen. the present study reveals an anti-adipogenic effect of DS in vitro and in vivo and highlights AMPK/MAPK signaling as targets for DS during adipogenesis.