Scoparone inhibits adipocyte differentiation through down-regulation of peroxisome proliferators-activated receptor γ in 3T3-L1 preadipocytes

Pseudotargeted lipidomics analysis of scoparone on glycerophospholipid metabolism in non-alcoholic steatohepatitis mice by LC-MRM-MS

As the inflammatory subtype of nonalcoholic fatty liver disease (NAFLD), the progression of nonalcoholic steatohepatitis (NASH) is associated with disorders of glycerophospholipid metabolism. Scoparone is the major bioactive component in Artemisia capillaris which has been widely used to treat NASH in traditional Chinese medicine. However, the underlying mechanisms of scoparone against NASH are not yet fully understood, which hinders the development of effective therapeutic agents for NASH. Given the crucial role of glycerophospholipid metabolism in NASH progression, this study aimed to characterize the differential expression of glycerophospholipids that is responsible for scoparone's pharmacological effects and assess its efficacy against NASH. Liquid chromatography-multiple reaction monitoring-mass spectrometry (LC-MRM-MS) was performed to get the concentrations of glycerophospholipids, clarify mechanisms of disease, and highlight insights into drug discovery. Additionally, pathologic findings also presented consistent changes in high-fat diet-induced NASH model, and after scoparone treatment, both the levels of glycerophospholipids and histopathology were similar to normal levels, indicating a beneficial effect during the observation time. Altogether, these results refined the insights on the mechanisms of scoparone against NASH and suggested a route to relieve NASH with glycerophospholipid metabolism. In addition, the current work demonstrated that a pseudotargeted lipidomic platform provided a novel insight into the potential mechanism of scoparone action.

Evaluation of the Antioxidant Potential of Citrus medica from Different Geographical Regions and Characterization of Phenolic Constituents by LC-MS

The varying antioxidant potential of Citrus medica associated with different geographical regions makes the evaluation of C. medica for natural antioxidants essential. This work aimed to compare the antioxidant potential of the phenolic constituents from different geographical regions. The chemical compositions were characterized by ultra-high-performance liquid chromatography (UPLC) coupled with mass spectrometry (MS). A total of 67 compounds including 29 coumarin derivatives and 38 flavonoids were tentatively identified by UPLC-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). To evaluate the quality of C. medica from seven different geographical regions, water and 80% methanol fractions were subjected to quantitative analysis. Antioxidant potentials were determined by 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), iron chelation, and reduction methods. The samples collected from Sichuan province showed the highest content of total phenolic compounds. Combined with antioxidant results, the sample from Sichuan province presented good antioxidant activity. This study also showed that total phenolic compounds significantly contributed to the antioxidant activities (2,2-azinobis(3-ethyl-benzothiazoline-6-sulphonic acid) and radical scavenging activity) of C. medica samples (p < 0.01). These results provided chemical information and potential antioxidant value for further research, providing ideal evidence for the quality evaluation and exploitation of the source.

Effects of two triterpenoids from Nigella sativa seeds on insulin resistance of 3T3-L1 adipocytes

Insulin resistance (IR) is a physiological abnormality that occurs when insulin fails to activate the signal transduction pathway in target organs. It was found that supplementation of Nigella sativa seeds with oral antidiabetic medicines helps improve blood glucose control by enhanced β cells activity and alleviation of IR. However, the activities and related mechanisms of phytochemicals from N. sativa seeds have not been thoroughly explored. In this study, the effects of two triterpenoids, 3-O-[β-D-xylopyranose-(1→3)-α-L-rhamnose-(1→2)-α-L-arabinose]-28-O-[α-L-rhamnose-(1→4)-β-D-glucopyranose-L-(1→6)-β-D-glucopyranose]-hederagenin (Hxrarg) and 3-O-[β-D-xylopyranose-(1→3)-α-L-rhamnose-(1→2)-α-L-arabinose]-hederagenin (Hxra), on IR were studied by 3T3-L1 adipocytes model. The results demonstrated that Hxrarg and Hxra inhibited maturation of 3T3-L1 preadipocytes, dramatically stimulated glucose uptake of IR-3T3-L1 adipocytes, promoted transcription of IRS, AKT, PI-3K, and GLUT4 mRNA. Western Blot results suggested that Hxrarg and Hxra were able to markedly up-regulate expression of p-IRS, p-AKT, PI-3K, and GLUT4 proteins. These findings could provide a basic foundation for the continued development and application of N. sativa in medicine and functional foods.

Scoparone Improves Nonalcoholic Steatohepatitis Through Alleviating JNK/Sab Signaling Pathway-Mediated Mitochondrial Dysfunction

The activated c-Jun N-terminal kinase (JNK) specifically combined with SH3 domain-binding protein 5 (Sab) may mediate damage to the mitochondrial respiratory chain. Whether mitochondrial dysfunction induced by the JNK/Sab signaling pathway plays a pivotal role in the lipotoxic injury of nonalcoholic steatohepatitis (NASH) remains a lack of evidence. Scoparone, a natural compound from Traditional Chinese Medicine herbs, has the potential for liver protection and lipid metabolism regulation. However, the effect of scoparone on NASH induced by a high-fat diet (HFD) as well as its underlying mechanism remains to be elucidated. The HepG2 and Huh7 cells with/without Sab-knockdown induced by palmitic acid (PA) were used to determine the role of JNK/Sab signaling in mitochondrial dysfunction and cellular lipotoxic injury. To observe the effect of scoparone on the lipotoxic injured hepatocytes, different dose of scoparone together with PA was mixed into the culture medium of HepG2 and AML12 cells to incubate for 24 h. In addition, male C57BL/6J mice were fed with an HFD for 22 weeks to induce the NASH model and were treated with scoparone for another 8 weeks to investigate its effect on NASH. Molecules related to JNK/Sab signaling, mitochondrial function, and lipotoxic injury were detected in in vitro and/or in vivo experiments. The results showed that PA-induced activation of JNK/Sab signaling was blocked by Sab knockdown in hepatocytes, which improved mitochondrial damage, oxidative stress, hepatosteatosis, cell viability, and apoptosis. Scoparone demonstrated a similar effect on the PA-induced hepatocytes as Sab knockdown. For the NASH mice, treatment with scoparone also downregulated the activation of JNK/Sab signaling, improved histopathological changes of liver tissues including mitochondrial number and morphology, lipid peroxide content, hepatosteatosis and inflammation obviously, as well as decreased the serum level of lipid and transaminases. Taken together, this study confirms that activation of the JNK/Sab signaling pathway-induced mitochondrial dysfunction plays a crucial role in the development of NASH. Scoparone can improve the lipotoxic liver injury partially by suppressing this signaling pathway, making it a potential therapeutic compound for NASH.

Isolation of phenolic acids and tannin acids from Mangifera indica L. kernels as inhibitors of lipid accumulation in 3T3-L1 cells

Mango (Mangifera indica L.) kernels are usually discarded as waste, but they contain many pharmacological properties and bioactivities. In this study, we isolated antiobesity agents from mango kernels that inhibit intracellular lipid formation in 3T3-L1 adipocytes. Two phenolic acids, ethyl gallate and ethyl digallate, and 2 tannin acids, 1,2,3,4,6-penta-O-galloyl-β-d-glucose (PGG) and 3-O-digalloyl-1,2,4,6-tetra-O-β-d-glucose (HGG), were identified from mango kernels and were found to be suppressed lipid accumulation as evidenced by Oil Red O staining. Furthermore, ethyl digallate, PGG, and HGG significantly downregulated the mRNA expression of adipogenic transcription factors such as C/EBPα and PPARγ. However, ethyl gallate did not affect the expression of these transcription factors. Our findings reveal the presence of antiobesity compounds in mango kernels, implying its therapeutic role against obesity.

Exploring the Potential Mechanisms of Melilotus officinalis (L.) Pall. in Chronic Muscle Repair Patterns Using Single Cell Receptor-Ligand Marker Analysis and Molecular Dynamics Simulations

Information regarding the function of Melilotus officinalis (L.) Pall. in skeletal muscles is still unknown. In this study, we explored the possible regulatory targets of M. (L.) Pall. that affects the repair patterns in chronic muscle injury. We analyzed the potential target genes and chemical composition of M. (L.) Pall. and constructed a "drug-component-disease target genes" network analysis. Five active ingredients and 87 corresponding targets were obtained. Muscle-tendon junction (MTJ) cells were used to perform receptor-ligand marker analysis using the CellphoneDB algorithm. Targets of M. (L.) Pall. were screened further for the cellular ligand-receptor protein action on MTJs. Enrichment analysis suggests that those protein-associated ligand receptors may be associated with a range of intercellular signaling pathways. Molecular docking validation was then performed. Five proteins (CCL2, VEGFA, MMP2, MET, and EGFR) may be regulated by the active ingredient luteolin and scoparone. Finally, molecular dynamics simulations revealed that luteolin can stably target binding to MMP2. M. (L.) Pall. influences skeletal muscle repair patterns by affecting the fibroblast interactions in the muscle-tendon junctions through the active ingredients luteolin and scoparone.

Exploring the Molecular Mechanism of Action of Yinchen Wuling Powder for the Treatment of Hyperlipidemia, Using Network Pharmacology, Molecular Docking, and Molecular Dynamics Simulation

Background

Yinchen Wuling powder is often used to treat clinical hyperlipidemia, although its mechanism of action remains unclear. In this study, we aimed to investigate the active ingredients found in Yinchen Wuling powder and find its mechanism of action when treating hyperlipidemia, using a combination of network pharmacology, molecular docking, and molecular dynamics simulation approaches.

Methods

The TCMSP database was used to obtain the principle active ingredients found in Yinchen Wuling powder and the NCBI and DisGeNet databases were used to obtain the main target genes involved in hyperlipidemia, and the intersectional targets were obtained by EXCEL. We also used Cytoscape 3.7.2 software to construct a “Traditional Chinese Medicine-Active Ingredient-Target” network and use STRING platform to conduct “protein-protein interactional” (PPI) analyses on the intersection targets. Bioconductor software and RX 64 4.0.0 software were then used to perform GO functional enrichment analysis and KEGG pathway enrichment analysis on the targets. Molecular docking of core protein-ligand interactions was modeled using AutoDock Vina software. A simulation of molecular dynamics was conducted for the optimal core protein-ligand obtained by molecular docking using Amber18 software.

Results

A total of 63 active ingredients were found in Yinchen Wuling powder, corresponding to 175 targets, 508 hyperlipidemia targets, and 55 intersection targets in total. Cytoscape 3.7.2 showed that the key active ingredients were quercetin, isorhamnetin, taxifolin, demethoxycapillarisin, and artepillin A. The PPI network showed that the key proteins involved were AKT1, IL6, VEGFA, and PTGS2. GO enrichment analysis found that genes were enriched primarily in response to oxygen levels and nutrient levels of the vesicular lumen and were associated with membrane rafts. These were mainly enriched in AGE-RAGE (advanced glycation end products-receptor for advanced glycation end products) signaling pathway in diabetic complications, fluid shear stress, and atherosclerosis, as well as other pathways. The molecular docking results indicated key binding activity between PTGS2-quercetin, PTGS2-isorhamnetin, and PTGS2-taxifolin. Results from molecular dynamics simulations showed that PTGS2-quercetin, PTGS2-isorhamnetin, and PTGS2-taxifolin bound more stably, and their binding free energies were PTGS2-quercetin -29.5 kcal/mol, PTGS2-isorhamnetin -32 kcal/mol, and PTGS2-taxifolin -32.9 kcal/mol.

Conclusion

This study is based on network pharmacology and reveals the potential molecular mechanisms involved in the treatment of hyperlipidemia by Yinchen Wuling powder.

The Pharmacological Effects and Pharmacokinetics of Active Compounds of Artemisia capillaris

Artemisia capillaris Thunb. (A.capillaris, Yin-Chen in Chinese) is a traditional medicinal herb with a wide spectrum of pharmacological properties ranging from effects against liver dysfunction to treatments of severe cirrhosis and cancer. We used relevant keywords to search electronic databases, including PubMed, Medline, and Google Scholar, for scientific contributions related to this medicinal herb and the pharmacokinetics of its components. The pharmaceutical effects of A.capillaris contribute to the treatment not only of viral hepatitis, cirrhosis, and hepatocellular hepatoma, but also metabolic syndrome, psoriasis, and enterovirus in the clinic. The bioactive compounds, including scoparone, capillarisin, scopoletin, and chlorogenic acid, exhibit antioxidant, anti-inflammatory, antisteatotic, antiviral, and antitumor properties, reflecting the pharmacological effects of A.capillaris. The pharmacokinetics of the main bioactive compounds in A. capillaris can achieve a maximum concentration within 1 hour, but only chlorogenic acid has a relatively long half-life. Regarding the use of the A. capillaris herb by health professionals to treat various diseases, the dosing schedule of this herb should be carefully considered to maximize therapeutic outcomes while lessening possible side effects.

Artemisia scoparia: Traditional uses, active constituents and pharmacological effects

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia scoparia Waldst.et Kit (A. scoparia), is an important medicinal plant mainly distributed in China, Korea, Japan, Pakistan, India, Central Europe, Saudi Arabia and Iran. It has been used for a long history to treat fever, inflammation, jaundice, and infection, but systematic reviews about the medicinal uses of A. scoparia are still lacking.

AIM OF THE STUDY

This review is to provide up-to-date information on A. scoparia, including its botanical characteristics, medicinal resources, traditional uses, phytochemistry and pharmacological effects, in exploring therapeutic and scientific potentials.

MATERIALS AND METHODS

The information related to this article was systematically collected from the scientific literature databases including PubMed, Google Scholar, Web of Science, Science Direct, Springer, China National Knowledge Infrastructure, local books, PhD and MS dissertations, and other web sources.

RESULTS

Herein a total of 102 compounds, such as flavonoids, coumarins, chromones, steroids, volatile oil and phenolic acid isolated from A. scoparia are summarized. Among these compounds, the effects of flavonoids, coumarins and phenolic acids were extensively studied. We have comprehensively summarized modern pharmacological studies on A. scoparia and demonstrated A. scoparia and its active components have a wide range of pharmaceutical activities, such as anticancer, anti-inflammatory, antibacterial, liver protection, antiatherogenic, antiviral as well as neuroprotective functions.

CONCLUSIONS

As an important Chinese medicinal plant, modern pharmacological studies have demonstrated that A. scoparia has diverse bioactivities, especially on liver protection and anti-inflammatory activities. These prominent bioactivities highlight prospects on new drug development. Nevertheless, the comprehensive evaluation, long-term in vivo toxicity, and clinical efficacy of A. scoparia require further in-depth research.

Hydro alcoholic green tea extract effect on high fat diet treated NMRI mice and 3T3L1 cells

Purpose

In order to counteract the obesity has epidemics, since current anti-obesity drugs effects remain limited, there is a need to provide new options. As a project aiming to assess potential anti obesity natural compounds, the effects of consumption of a minimal dose of green tea hydro alcoholic extract (GT) on adipocyte differentiation of 3T3L1 cell line were investigated.

Methods

Obesity was induced in female NMRI mice (which are less used overall) by the use of a high fat diet. Mice were divided into four groups of control (C), treated control (TC), obese (O) and treated obese (TO). TC and TO groups received 8 mg/Kg/day of GT for 8 weeks, and weighted weekly, after what biochemical and histological parameters were measured. GT was used at doses of 100,150 and 200 µg/ml on 3T3L1, and staining with Oil-red-O was done for estimation of fat droplet accumulation.

Results

Body weight was found to be affected significantly by GT. Blood glucose levels did not show significant changes between groups, while triglycerides levels of the O group was significantly higher than the C group, but the TO group showed no significant difference with the C group upon GT treatment. Liver and visceral fat tissues showed more normalized tissue and less fat accumulation in the TO group. TO and TC groups showed an ameliorated morphologic state of liver tissues. GT was also able to decrease fat droplet formation in a dose-dependent manner.

Conclusions

Adding a minimal amount of GT to the daily consumption may have preventive effects on fat accumulation in healthy subjects, while in obese cases, GT shows significant therapeutic effect.

Artemisia scoparia and Metabolic Health: Untapped Potential of an Ancient Remedy for Modern Use

Botanicals have a long history of medicinal use for a multitude of ailments, and many modern pharmaceuticals were originally isolated from plants or derived from phytochemicals. Among these, artemisinin, first isolated from Artemisia annua, is the foundation for standard anti-malarial therapies. Plants of the genus Artemisia are among the most common herbal remedies across Asia and Central Europe. The species Artemisia scoparia (SCOPA) is widely used in traditional folk medicine for various liver diseases and inflammatory conditions, as well as for infections, fever, pain, cancer, and diabetes. Modern in vivo and in vitro studies have now investigated SCOPA's effects on these pathologies and its ability to mitigate hepatotoxicity, oxidative stress, obesity, diabetes, and other disease states. This review focuses on the effects of SCOPA that are particularly relevant to metabolic health. Indeed, in recent years, an ethanolic extract of SCOPA has been shown to enhance differentiation of cultured adipocytes and to share some properties of thiazolidinediones (TZDs), a class of insulin-sensitizing agonists of the adipogenic transcription factor PPARγ. In a mouse model of diet-induced obesity, SCOPA diet supplementation lowered fasting insulin and glucose levels, while inducing metabolically favorable changes in adipose tissue and liver. These observations are consistent with many lines of evidence from various tissues and cell types known to contribute to metabolic homeostasis, including immune cells, hepatocytes, and pancreatic beta-cells. Compounds belonging to several classes of phytochemicals have been implicated in these effects, and we provide an overview of these bioactives. The ongoing global epidemics of obesity and metabolic disease clearly require novel therapeutic approaches. While the mechanisms involved in SCOPA's effects on metabolic, anti-inflammatory, and oxidative stress pathways are not fully characterized, current data support further investigation of this plant and its bioactives as potential therapeutic agents in obesity-related metabolic dysfunction and many other conditions.

Deoxynivalenol Exposure Suppresses Adipogenesis by Inhibiting the Expression of Peroxisome Proliferator-Activated Receptor Gamma 2 (PPARγ2) in 3T3-L1 Cells

Deoxynivalenol (DON)-a type B trichothecene mycotoxin, mainly produced by the secondary metabolism of Fusarium-has toxic effects on animals and humans. Although DON's toxicity in many organs including the adrenal glands, thymus, stomach, spleen, and colon has been addressed, its effects on adipocytes have not been investigated. In this study, 3T3-L1 cells were chosen as the cell model and treated with less toxic doses of DON (100 ng/mL) for 7 days. An inhibition of adipogenesis and decrease in triglycerides (TGs) were observed. DON exposure significantly downregulated the expression of PPARγ2 and C/EBPα, along with that of other adipogenic marker genes in 3T3-L1 cells and BALB/c mice. The anti-adipogenesis effect of DON and the downregulation of the expression of adipogenic marker genes were effectively reversed by PPARγ2 overexpression. The repression of PPARγ2's expression is the pivotal event during DON exposure regarding adipogenesis. DON exposure specifically decreased the di-/trimethylation levels of Histone 3 at lysine 4 in 3T3-L1 cells, therefore weakening the enrichment of H3K4me2 and H3K4me3 at the Pparγ2 promoter and suppressing its expression. Conclusively, DON exposure inhibited PPARγ2 expression via decreasing H3K4 methylation, downregulated the expression of PPARγ2-regulated adipogenic marker genes, and consequently suppressed the intermediate and late stages of adipogenesis. Our results broaden the current understanding of DON's toxic effects and provide a reference for addressing the toxicological mechanism of DON's interference with lipid homeostasis.

5'-hydroxy Auraptene stimulates osteoblast differentiation of bone marrow-derived mesenchymal stem cells via a BMP-dependent mechanism

Background

Identifying bone anabolic agents is a superior strategy for the treatment of osteoporosis. Naturally, derived coumarin derivatives have shown osteoanabolic effect in vitro and in vivo. In this study, we investigated the effect of 5′-Hydroxy Auraptene (5′-HA), a coumarin derivative that newly isolated from Lotus lalambensis Schweinf on the differentiation of the mouse bone marrow-derived mesenchymal (skeletal) stem cells (mBMSCs) into osteoblast and adipocyte.

Methods

The effect of 5′-HA on mBMSCs cell proliferation and osteoblast differentiation was assessed by measuring cell viability, quantitative alkaline phosphatase (ALP) activity assay, Alizarin red staining for matrix mineralization and osteogenic gene array expression. Adipogenesis was measured by Oil Red O staining and quantitative real time PCR (qPCR) analysis of adipogenic markers. Regulation of BMPs signaling pathways by 5′-HA was measured by Western blot analysis and qPCR.

Results

5′-HA showed to stimulate the differentiation of mBMSCs into osteogenic cell lineage in a dose-dependent manner, without affecting their differentiation into adipocytic cell lineage. Treatment of mBMSCs with 5′-HA showed to promote significantly the BMP2-induced osteogenesis in mBMSCs via activating Smad1/5/8 phosphorylation and increasing Smad4 expression. Blocking of BMP signaling using BMPR1 selective inhibitor LDN-193189 significantly inhibited the stimulatory effect of 5′-HA on osteogenesis.

Conclusions

Our data identified 5′-HA, as a novel coumarin derivative that function to stimulate the differentiation of mBMSCs into osteoblasts in BMP-signaling dependent mechanism.

Electronic supplementary material

The online version of this article (10.1186/s12929-019-0544-7) contains supplementary material, which is available to authorized users.

Label-free quantitative proteomics identifies transforming growth factor β1 (TGF-β1) as an inhibitor of adipogenic transformation in OP9-DL1 cells and primary thymic stromal cells

Background

Adipocyte accumulation is a predominant feature of age-related thymic involution, but the mechanisms responsible for thymic adipogenesis remain to be elucidated. The aim of this study was to identify key regulators in thymic adipogenesis. We used rosiglitazone, a potent peroxisome proliferator-activated receptor γ (PPARγ) agonist, to induce adipogenic differentiation of OP9-DL1 cells, and investigated the differentially expressed proteins during adipogenic differentiation by using label-free quantitative proteomics. Furthermore, the effects of transforming growth factor β1 (TGF-β1) on rosiglitazone-induced adipogenic differentiation of OP9-DL1 cells as well as the underlying mechanisms were also investigated.

Results

Proteomic analysis identified 139 proteins differed significantly in rosiglitazone-treated cells compared with dimethyl sulphoxide (DMSO)-treated cells. Rosiglitazone-induced adipogenic differentiation was inhibited by TGF-β1 treatment in OP9-DL1 cells and primary thymic stromal cells. Real-time PCR analysis showed significant increases in PPARγ and fatty acid binding protein 4 mRNA levels in rosiglitazone-treated cells, which were inhibited by TGF-β1 treatment. TGF-β1 down-regulated PPARγ expression at both mRNA and protein levels in OP9-DL1 cells. Chromatin immunoprecipitation analysis demonstrated that TGF-β1 enhanced the binding of Smad2/3 and histone deacetylase 1, but reduced the binding of H3K14ac to the promoter of PPARγ gene. TGF-β1 partially reversed the inhibitory effects of rosiglitazone on the expression of Axin2 and β-catenin protein levels. TGF-β1 inhibited rosiglitazone-induced adipogenic transformation in OP9-DL1 cells by down-regulation of PPARγ and activation of the canonical Wnt/β-catenin signaling pathway.

Conclusion

Taken together, activation of TGF-β pathway may serve as a useful strategy to prevent thymic adiposity in age-related thymic involution.

Electronic supplementary material

The online version of this article (10.1186/s13578-019-0311-1) contains supplementary material, which is available to authorized users.

Anti-obesity effects of Diospyros lotus leaf extract in mice with high-fat diet-induced obesity

Diospyros (D.) lotus has been demonstrated to have antioxidant and anti‑inflammatory properties. The purpose of the present study was to evaluate the effect of D. lotus leaf water extract (DLE) on high‑fat diet (HFD)‑induced obesity in C57BL/6 mice. The present study first investigated the effect of DLE on the lipid accumulation and triglyceride (TG) contents in 3T3‑L1 cells, and the results revealed that treatment with DLE suppressed the lipid accumulation and TG level. Subsequently, the anti‑obesity effects of DLE were investigated in vivo. Oral administration of DLE reduced the body weight gain, food efficiency ratio, and liver and visceral fat weight in mice fed with a HFD. DLE administration in these mice also reduced TG, total cholesterol, low‑density lipoprotein cholesterol, glucose, insulin and leptin levels, as well as the atherogenic index. Furthermore, DLE administration decreased hepatic steatosis, as well as serum aspartate transaminase, alanine transaminase and alkaline phosphatase levels in mice fed with HFD. It was further observed that treatment of the HFD‑fed mice with DLE prevented lipid peroxidation, while it recovered glutathione depletion and the activities of superoxide dismutase, catalase and glutathione peroxidase. In conclusion, the current study suggests that the anti‑obesity effect of DLE may provide positive insights as a potential functional food ingredient for the prevention of obesity.

The Inhibitory Effects of Djulis (Chenopodium formosanum) and Its Bioactive Compounds on Adipogenesis in 3T3-L1 Adipocytes

The aim of this study was to provide new insights into the role of the ethanolic extracts of Djulis (Chenopodium formosanum, EECF) and its bioactive compounds in preventing adipogenesis in 3T3-L1 adipocytes. The results demonstrated EECF significantly inhibited oil red O-stained material (OROSM), triglyceride levels and glycerol-3-phosphate dehydrogenase (GPDH) activity in 3T3-L1 adipocytes. The expression of the critical molecules involved in lipid synthesis such as PPARγ, C/EBPα and SREBP-1c was attenuated in EECF-treated cells. According to HPLC-DAD and HPLC-MS/MS analysis, rutin, kaempferol, betanin and another nine compounds were present in EECF. The suppression of lipid accumulation by rutin, kaempferol and betanin occurred by decreasing the gene expression of PPARγ, C/EBPα and SREBP-1c. Taken together, these findings suggest the presence of bioactive compounds in EECF may partly account for the anti-adipogenesis of EECF and EECF is therefore a potentially lipid lowering functional food.

Coumarins as potential antidiabetic agents

OBJECTIVES

Even with great advances in modern medicine and therapeutic agent development, the search for effective antidiabetic drugs remains challenging. Coumarins are secondary metabolites found widely in nature plants and used mainly in anticoagulation and antithrombotic therapy. Over the past two decades, however, there has been an increasing body of literatures related to the effects of coumarins and their derivatives on diabetes and its complications. This review aimed to focus on research findings concerning the effects of coumarins against diabetes and its complications using in-vitro and in-vivo animal models, and also to discuss cellular and molecular mechanisms underlying these effects.

KEY FINDINGS

The search for new coumarins against diabetes and it complications, either isolated from traditional medicine or chemically synthesized, has been constantly expanding. The cellular and molecular mechanisms involved include protecting pancreatic beta cells from damage, improving abnormal insulin signalling, reducing oxidative stress/inflammation, activating AMP-activated protein kinase (AMPK), inhibiting α-glucosidases and ameliorating diabetic complications.

CONCLUSIONS

The effects and mechanisms of coumarins and their derivatives upon diabetes and its complications are discussed in current review. Further investigations remain to be carried out to develop a promising antidiabetic agent based on coumarin cores.

Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice

Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor, the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90%) upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP)-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

Anti-oxidant and anti-adipogenic effects of acorn (Quercus acutissima CARR.) shell extracts via regulation of wnt signaling in 3T3-L1 cells

Acorn (Quercus acutissima CARR.) is a nut from the Fagaceae family that has been used in traditional medicine for many years. However, shells from acorns are regarded as a by-product and are mostly discarded. Anti-adipogenic activities of acorn shells were investigated using 3T3-L1 cells and methanol shell extracts (AE-M). AE-M demonstrated Cu²⁺-chelation activities and anti-oxidant activities via reduction of oxidative stress levels induced using AAPH. Six days after adipocyte differentiation, 50 and 100 μg/mL AE-M completely suppressed 3T3-L1 adipogenesis and the anti-adipogenic effect was stronger than for the positive control 50 μM quercetin. Treatment with AE-M in 3T3-L1 cells reduced mRNA expression levels of adipogenic genes. AE-M-inhibition was found in pre-adipogenic, early, and intermediate stages of adipogenesis in 3T3-L1 cells. The Wnt/β-catenin signaling pathway is required for AE-M-inhibition of 3T3-L1 adipogenesis.

Suppressive Effects of Barley β-Glucans with Different Molecular Weight on 3T3-L1 Adipocyte Differentiation

In this study, 2 β-glucans with different molecular weight were prepared and purified from hull-less barley bran. The aim was to evaluate their effects on the differentiation of 3T3-L1 pre-adipocytes. Results showed that barley β-glucans inhibited the differentiation of 3T3-L1 pre-adipocytes induced by differentiation medium in a dose-dependent manner, the suppressive effect of high-molecular-weight barley β-glucans (552 kDa, BGH) was stronger (P < 0.05) than that of low-molecular-weight barley β-glucan (32 kDa, BGL), evidenced by the significantly decrease (P < 0.05) of Oil-red O staining and intracellular triglyceride content in the mature adipocytes. Besides, gene expression analysis and Western Blot analysis revealed that both BGH and BGL inhibited the mRNA and protein levels of adipogenesis related transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding protein α (C/EBPα) which are principal regulators of adipogenesis. Furthermore, the mRNA and protein expression levels of PPARγ target genes in adipose tissue including adipocyte fatty acid binding protein (ap2), lipoprotein lipase (LPL), uncoupling protein-2 (UCP-2), and glucose-transporter 4 (Glut4) in 3T3-L1 cells was also markedly downregulated (P < 0.05). These findings were anticipated to help develop barley β-glucans based functional food for the management of obesity.

Cocoa tea (Camellia ptilophylla) water extract inhibits adipocyte differentiation in mouse 3T3-L1 preadipocytes

Cocoa tea (Camellia ptilophylla) is a naturally decaffeinated tea plant. Previously we found that cocoa tea demonstrated a beneficial effect against high-fat diet induced obesity, hepatic steatosis, and hyperlipidemia in mice. The present study aimed to investigate the anti-adipogenic effect of cocoa tea in vitro using preadipocytes 3T3-L1. Adipogenic differentiation was confirmed by Oil Red O stain, qPCR and Western blot. Our results demonstrated that cocoa tea significantly inhibited triglyceride accumulation in mature adipocytes in a dose-dependent manner. Cocoa tea was shown to suppress the expressions of key adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma (PPAR γ) and CCAAT/enhancer binding protein (C/EBP α). The tea extract was subsequently found to reduce the expressions of adipocyte-specific genes such as sterol regulatory element binding transcription factor 1c (SREBP-1c), fatty acid synthase (FAS), Acetyl-CoA carboxylase (ACC), fatty acid translocase (FAT) and stearoylcoenzyme A desaturase-1 (SCD-1). In addition, JNK, ERK and p38 phosphorylation were inhibited during cocoa tea inhibition of 3T3-L1 adipogenic differentiation. Taken together, this is the first study that demonstrates cocoa tea has the capacity to suppress adipogenesis in pre-adipocyte 3T3-L1 similar to traditional green tea.

Isoflavones in Chickpeas Inhibit Adipocyte Differentiation and Prevent Insulin Resistance in 3T3-L1 Cells

Diabetes mellitus is a metabolic disease characterized by hyperglycemia arising from defects in insulin secretion. This study investigated the effects of isoflavones in chickpea sprouts germinated in light (IGL) and isoflavones in chickpea seeds (ICS) on insulin resistance through their role in suppression of 3T3-L1 adipocyte differentiation. Results showed that IGL and ICS inhibit the differentiation of 3T3-L1 pre-adipocytes induced by differentiation medium in a dose-dependent manner, and the suppressive effect of IGL was stronger (p < 0.05) than that of ICS, evidenced by a decrease of Oil Red O staining and intracellular triacylglycerol content in the mature adipocytes. IGL and ICS also stimulated glucose uptake significantly (p < 0.05). Besides, IGL and ICS treatment caused a significant decrease in mRNA and protein expression levels of adipogenesis-related transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding protein α (C/EBPα). Furthermore, the mRNA and protein expression levels of adipocyte fatty acid-binding protein (ap2), lipoprotein lipase (LPL), uncoupling protein-2 (UCP-2), and glucose transporter 4 (Glut4) in 3T3-L1 cells were also markedly down-regulated (p < 0.05).

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.

Suppressive effects of saponin-enriched extracts from quinoa on 3T3-L1 adipocyte differentiation

This study was performed to investigate the effect of quinoa saponins (QS) on the differentiation of 3T3-L1 preadipocytes.

Modes-of-Action Related to Repeated Dose Toxicity: Tissue-Specific Biological Roles of PPAR γ Ligand-Dependent Dysregulation in Nonalcoholic Fatty Liver Disease

Comprehensive understanding of the precise mode of action/adverse outcome pathway (MoA/AOP) of chemicals becomes a key step towards superseding the current repeated dose toxicity testing methodology with new generation predictive toxicology tools. The description and characterization of the toxicological MoA leading to non-alcoholic fatty liver disease (NAFLD) are of specific interest, due to its increasing incidence in the modern society. Growing evidence stresses on the PPAR γ ligand-dependent dysregulation as a key molecular initiating event (MIE) for this adverse effect. The aim of this work was to analyze and systematize the numerous scientific data about the steatogenic role of PPAR γ . Over 300 papers were ranked according to preliminary defined criteria and used as reliable and significant sources of data about the PPAR γ -dependent prosteatotic MoA. A detailed analysis was performed regarding proteins which PPAR γ -mediated expression changes had been confirmed to be prosteatotic by most experimental evidence. Two probable toxicological MoAs from PPAR γ ligand binding to NAFLD were described according to the Organisation for Economic Cooperation and Development (OECD) concepts: (i) PPAR γ activation in hepatocytes and (ii) PPAR γ inhibition in adipocytes. The possible events at different levels of biological organization starting from the MIE to the organ response and the connections between them were described in details.