This study aims to investigate the in vitro mechanisms underlying the beneficial effects of puerarin on hepatic insulin resistance(IR) based on the carbohydrate response element-binding protein(ChREBP)/peroxisome proliferator-activated receptor(PPAR)α/PPARγ axis involved in glucose and lipid metabolism. An IR-HepG2 cell model was established by treating cells with dexamethasone for 48 h, and the cells were then treated with 10, 20, and 40 μmol·L~(-1) puerarin for 24 h. Glucose levels and output in the extracellular fluid were measured by the glucose oxidase method, while cell viability was assessed by the cell counting kit-8(CCK-8) assay. The adenosine triphosphate(ATP) content and glycogen synthesis were evaluated through chemiluminescence and periodic acid-Schiff staining, respectively. Western blot was employed to quantify the protein levels of forkhead box protein O1(FoxO1), phosphorylated forkhead box protein O1 [p-FoxO1(Ser256)], glucagon, phosphofructokinase, liver type(PFKL), pyruvate kinase L-R(PKLR), pyruvate dehydrogenase complex 1(PDHA1), insulin receptor substrate 2(IRS2), phosphatidylinositol 3-kinase p85(PI3KR1), phosphorylated protein kinase B [p-Akt(Thr308)], glycogen synthase(GYS), glycogen phosphorylase, liver type(PYGL), adiponectin(ADPN), ChREBP, PPARα, and PPARγ. Additionally, the protein levels of acetyl-CoA carboxylase 1(ACC1), phosphorylated ATP citrate lyase [p-ACLY(Ser455)], sterol regulatory element binding protein 1c(SREBP-1c), peroxisome proliferator-activated receptor gamma coactivator 1α(PGC1α), carnitine palmitoyltransferase 1α(CPT1α), and glucagon receptor(GCGR) were also determined. Immunofluorescence was employed to visualize the expression and nuclear location of ChREBP/PPARα/PPARγ. Furthermore, quantitative PCR with the antagonists GW6471 and GW9662 was employed to assess Pparα, Pparγ, and Chrebp. The findings indicated that puerarin effectively reduced both the glucose level and glucose output in the extracellular fluid of IR-HepG2 cells without obvious effect on the cell viability, and it increased intracellular glycogen and ATP levels. Puerarin down-regulated the protein levels of FoxO1 and glucagon while up-regulating the protein levels of p-FoxO1(Ser256), PFKL, PKLR, PDHA1, IRS2, PI3KR1, p-Akt(Thr308), GYS, PYGL, ADPN, ACC1, SREBP-1c, p-ACLY(Ser455), PGC1α, CPT1α, and GCGR in IR-HepG2 cells. Furthermore, puerarin up-regulated both the mRNA and protein levels of ChREBP, PPARα, and PPARγ and promoted the translocation into the nucleus. GW6471 was observed to down-regulate the expression of Pparα while up-regulating the expression of Chrebp and Pparγ. GW9662 down-regulated the expression of Pparγ while up-regulating the expression of Pparα, with no significant effect on Chrebp. In summary, puerarin activated the hepatic ChREBP/PPARα/PPARγ axis, thereby coordinating the glucose and lipid metabolism, promoting the conversion of glucose to lipids to exert the blood glucose-lowering effect.
Isoflavones/pharmacology* ; Humans ; PPAR gamma/genetics* ; Hep G2 Cells ; Glucose/metabolism* ; Lipid Metabolism/drug effects* ; PPAR alpha/genetics* ; Liver/drug effects* ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics* ; Insulin Resistance

OBJECTIVES: To investigate the effect of curcumin on lipid metabolism in non-small cell lung cancer (NSCLC) and its molecular mechanism. METHODS: The inhibitory effect of curcumin (0-70 μmol/L) on proliferation of A549 and H1299 cells was assessed using MTT assay, and 20 and 40 μmol/L curcumin was used in the subsequent experiments. The effect of curcumin on lipid metabolism was evaluated using cellular uptake assay, wound healing assay, triglyceride (TG)/free fatty acid (NEFA) measurements, and Oil Red O staining. Western blotting was performed to detect the expressions of PGC-1α, PPAR-α, and HIF-1α in curcumin-treated cells. Network pharmacology was used to predict the metabolic pathways, and the results were validated by Western blotting. In a nude mouse model bearing A549 cell xenograft, the effects of curcumin (20 mg/kg) on tumor growth and lipid metabolism were assessed by measuring tumor weight and observing the changes in intracellular lipid droplets. RESULTS: Curcumin concentration-dependently inhibited the proliferation of A549 and H1299 cells and significantly reduced TG and NEFA levels and intracellular lipid droplets. Western blotting revealed that curcumin significantly upregulated PGC-1α and PPAR‑α expressions in the cells. KEGG pathway enrichment analysis predicted significant involvement of the HIF-1 signaling pathway in curcumin-treated NSCLC, suggesting a potential interaction between HIF-1α and PPAR‑α. Western blotting confirmed that curcumin downregulated the expression of HIF-1α. In the tumor-bearing mice, curcumin treatment caused significant reduction of the tumor weight and the number of lipid droplets in the tumor cells. CONCLUSIONS Curcumin inhibits NSCLC cell proliferation and lipid metabolism by downregulating the HIF-1α pathway.
Curcumin/pharmacology* ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Animals ; Lipid Metabolism/drug effects* ; Carcinoma, Non-Small-Cell Lung/pathology* ; Lung Neoplasms/pathology* ; Mice, Nude ; Down-Regulation ; Mice ; Cell Proliferation/drug effects* ; Cell Line, Tumor ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; PPAR alpha/metabolism* ; Signal Transduction/drug effects* ; A549 Cells

OBJECTIVES: To investigate the effect of Ching Shum Pills (CSP) for alleviating non-alcoholic fatty liver disease (NAFLD) and the underlying mechanism. METHODS: In a mouse model of NAFLD, the therapeutic effect of CSP was evaluated by measuring serum glucose, lipid profiles (TC, TG, LDL-C, HDL-C), and hepatic function markers. Network pharmacology was employed to identify active compounds in CSP and their targets using TCMSP, HERB, SwissTargetPrediction, GeneCards, OMIM, and DisGeNET. Protein-protein interaction (PPI) networks, Gene Ontology (GO), and KEGG pathway analyses were conducted. Molecular docking (AutoDock Vina) was used to assess the compound-target binding affinities. Quantitative real-time PCR (qRT-PCR) was used to validate the mRNA expressions of the core genes in the liver tissue of the mouse models. RESULTS: In the mouse model of NAFLD, treatment with CSP significantly reduced body weight gain and serum TG levels of the mice, and high-dose CSP treatment resulted in obvious reduction of ALT levels and hepatic fat accumulation. Network pharmacology analysis identified quercetin and 2-monolinolenin as the key bioactives in CSP, which target TNF, AKT1, IL6, TP53, and ALB. Docking simulations suggested strong binding between the two core compounds and their target proteins. The results of qRT-PCR showed that high-fat diet induced significant downregulation of Tp53, Cpt1, and Ppara expressions in mice, which was effectively reversed by CSP treatment. CONCLUSIONS CSP can improve lipid metabolism disorders in NAFLD mice through a regulatory mechanism involving multiple targets and pathways to reduce liver fat accumulation and protect liver function. The key components in CSP such as quercetin and linolenic acid monoacylglycerol may participate in the regulation of such metabolic processes as fatty acid oxidation by targeting TP53.
Animals ; Non-alcoholic Fatty Liver Disease/drug therapy* ; Mice ; Drugs, Chinese Herbal/pharmacology* ; Lipid Metabolism/drug effects* ; Molecular Docking Simulation ; Disease Models, Animal ; Liver/metabolism* ; Male ; Lipid Metabolism Disorders/drug therapy* ; PPAR alpha/metabolism* ; Mice, Inbred C57BL ; Network Pharmacology

OBJECTIVE: To Investigate the effects of lithocholic acid (LCA) on the balance between osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). METHODS: Twelve 10-week-old SPF C57BL/6J female mice were randomly divided into an experimental group (undergoing bilateral ovariectomy) and a control group (only removing the same volume of adipose tissue around the ovaries), with 6 mice in each group. The body mass was measured every week after operation. After 4 weeks post-surgery, the weight of mouse uterus was measured, femur specimens of the mice were taken for micro-CT scanning and three-dimensional reconstruction to analyze changes in bone mass. Tibia specimens were taken for HE staining to calculate the number and area of bone marrow adipocytes in the marrow cavity area. ELISA was used to detect the expression of bone turnover markers in the serum. Liver samples were subjected to real-time fluorescence quantitative PCR (RT-qPCR) to detect the expression of key genes related to bile acid metabolism, including cyp7a1, cyp7b1, cyp8b1, and cyp27a1. BMSCs were isolated by centrifugation from 2 C57BL/6J female mice (10-week-old). The third-generation cells were exposed to 0, 1, 10, and 100 μmol/L LCA, following which cell viability was evaluated using the cell counting kit 8 assay. Subsequently, alkaline phosphatase (ALP) staining and oil red O staining were conducted after 7 days of osteogenic and adipogenic induction. RT-qPCR was employed to analyze the expressions of osteogenic-related genes, namely ALP, Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), as well as adipogenic-related genes including Adiponectin (Adipoq), fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ (PPARγ). RESULTS: Compared with the control group, the body mass of the mice in the experimental group increased, the uterus atrophied, the bone mass decreased, the bone marrow fat expanded, and the bone metabolism showed a high bone turnover state. RT-qPCR showed that the expressions of cyp7a1, cyp8b1, and cyp27a1, which were related to the key enzymes of bile acid metabolism in the liver, decreased significantly ( P<0.05), while the expression of cyp7b1 had no significant difference ( P>0.05). Intervention with LCA at concentrations of 1, 10, and 100 μmol/L did not demonstrate any apparent toxic effects on BMSCs. Furthermore, LCA inhibited the expressions of osteogenic-related genes (ALP, Runx2, and OCN) in a dose-dependent manner, resulting in a reduction in ALP staining positive area. Concurrently, LCA promoted the expressions of adipogenic-related genes (Adipoq, FABP4, and PPARγ), and an increase in oil red O staining positive area. CONCLUSION After menopause, the metabolism of bile acids is altered, and secondary bile acid LCA interferes with the balance of osteogenic and adipogenic differentiation of BMSCs, thereby affecting bone remodelling.
Female ; Mice ; Animals ; Core Binding Factor Alpha 1 Subunit/pharmacology* ; PPAR gamma/metabolism* ; Steroid 12-alpha-Hydroxylase/metabolism* ; Mice, Inbred C57BL ; Cell Differentiation ; Osteogenesis ; Mesenchymal Stem Cells ; Bile Acids and Salts/pharmacology* ; Bone Marrow Cells ; Cells, Cultured ; Azo Compounds

The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα^-/-+ND) group and ketogenic diet (PPARα^-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα^-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα^-/-+ND group, the PPARα^-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.
Animals ; Mice ; Adipose Tissue, Brown/metabolism* ; PPAR alpha/pharmacology* ; Diet, Ketogenic ; Uncoupling Protein 1/metabolism* ; Blood Glucose/metabolism* ; Temperature ; Mice, Inbred C57BL ; Liver ; Adipose Tissue/metabolism*

The aim of this study was to investigate the effect of activating transcription factor 3 (ATF3) on the differentiation of intramuscular preadipocytes in goat, and to elucidate its possible action pathway at the molecular level. In this study, the recombinant plasmid of goat pEGFP-N1-ATF3 was constructed, and the intramuscular preadipocytes were transfected with liposomes. The relative expression levels of adipocyte differentiation marker genes were detected by quantitative real-time PCR (qRT-PCR). After transfection of goat intramuscular preadipocytes with the goat pEGFP-N1-ATF3 overexpression vector, it was found that the accumulation of lipid droplets was inhibited, and the adipocyte differentiation markers PPARγ, C/EBPα and SREBP1 were extremely significantly down-regulated (P < 0.01), while C/EBPβ and AP2 were significantly down-regulated (P < 0.05). The ATF3 binding sites were predicted to exist in the promoter regions of PPARγ, C/EBPα and AP2 by the ALGGEN PROMO program. The overexpression of goat ATF3 inhibits the accumulation of lipid droplets in intramuscular preadipocytes, and this effect may be achieved by down-regulating PPARγ, C/EBPα and AP2. These results may facilitate elucidation of the regulatory mechanism of ATF3 in regulating the differentiation of goat intramuscular preadipocytes.
3T3-L1 Cells ; Activating Transcription Factor 3/pharmacology* ; Adipocytes ; Adipogenesis/genetics* ; Animals ; CCAAT-Enhancer-Binding Protein-alpha/pharmacology* ; Cell Differentiation ; Goats ; Mice ; PPAR gamma/metabolism*

Objective To explore the potential targets of triclosan in the treatment of nonalcoholic fatty liver disease(NAFLD) and to provide new clues for the future research on the application of triclosan. Methods The targets of triclosan and NAFLD were obtained via network pharmacology.The protein-protein interaction network was constructed with the common targets shared by triclosan and NAFLD.The affinity of triclosan to targets was verified through molecular docking.Gene ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment were carried out to analyze the key targets and the potential mechanism of action.NAFLD model was established by feeding male C57BL/6J mice with high-fat diet for 12 weeks.The mice were randomly assigned into a model group and a triclosan group [400 mg/(kg·d),gavage once a day for 8 weeks].The hematoxylin-eosin(HE) staining was used for observation of the pathological changes and oil red O staining for observation of fat deposition in mouse liver.Western blotting was employed to detect the protein level of peroxisome proliferator-activated receptor alpha(PPARα) in the liver tissue. Results Triclosan and NAFLD had 34 common targets,19 of which may be the potential targets for the treatment,including albumin(ALB),PPARα,mitogen-activated protein kinase 8(MAPK8),and fatty acid synthase.Molecular docking predicted that ALB,PPARα,and MAPK8 had good binding ability to triclosan.KEGG pathway enrichment showcased that the targets were mainly enriched in peroxisome proliferator-activated receptor signaling pathway,in which ALB and MAPK8 were not involved.Triclosan alleviated the balloon-like change and lipid droplet vacuole,decreased the lipid droplet area,and up-regulated the expression level of PPARα in mouse liver tissue. Conclusion PPARα is a key target of triclosan in the treatment of NAFLD,which may be involved in fatty acid oxidation through the peroxisome proliferator activated receptor signaling pathway.
Animals ; Liver/pathology* ; Male ; Mice ; Mice, Inbred C57BL ; Molecular Docking Simulation ; Network Pharmacology ; Non-alcoholic Fatty Liver Disease/drug therapy* ; PPAR alpha/therapeutic use* ; Triclosan/therapeutic use*

Endogenously eliminating the hematoma is a favorable strategy in addressing intracerebral hemorrhage (ICH). This study sought to determine the role of retinoid X receptor-α (RXR-α) in the context of hematoma absorption after ICH. Our results showed that pharmacologically activating RXR-α with bexarotene significantly accelerated hematoma clearance and alleviated neurological dysfunction after ICH. RXR-α was expressed in microglia/macrophages, neurons, and astrocytes. Mechanistically, bexarotene promoted the nuclear translocation of RXR-α and PPAR-γ, as well as reducing neuroinflammation by modulating microglia/macrophage reprograming from the M1 into the M2 phenotype. Furthermore, all the beneficial effects of RXR-α in ICH were reversed by the PPAR-γ inhibitor GW9662. In conclusion, the pharmacological activation of RXR-α confers robust neuroprotection against ICH by accelerating hematoma clearance and repolarizing microglia/macrophages towards the M2 phenotype through PPAR-γ-related mechanisms. Our data support the notion that RXR-α might be a promising therapeutic target for ICH.
Anilides/pharmacology* ; Cerebral Hemorrhage/drug therapy* ; Hematoma/drug therapy* ; Humans ; Macrophages ; Microglia ; Neuroprotection ; PPAR gamma ; Retinoid X Receptor alpha

Tanshinone Ⅱ_A( Tan Ⅱ_A),the liposoluble constituents of Salvia miltiorrhiza,can not only ameliorate the lipidic metabolism and decrease the concentration of lipid peroxidation,but also resist oxidation damage,scavenge free radicals and control inflammation,with a protective effect on prognosis after liver function impairment. Therefore,the studies on the exact mechanism of Tan Ⅱ_A in protecting the liver can provide important theoretical and experimental basis for the prevention and treatment effect of Tan Ⅱ_A for liver injury. In the present study,the protective effects and mechanism of Tan Ⅱ_A on 4-hydroxynonenal( 4-HNE)-induced liver injury were investigated in vitro. Normal liver tissues NCTC 1469 cells were used to induce hepatocytes oxidative damages by 4-HNE treatment. The protective effect of Tan Ⅱ_A on hepatocytes oxidative damages was detected by release amount of lactate dehydrogenase( LDH) analysis and hoechst staining. The protein expression changes of peroxisome proliferator-activated receptor α( PPARα) and peroxisome proliferator response element( PPRE) were analyzed by Western blot analysis in NCTC 1469 cells before and after Tan Ⅱ_A treatment. The gene expression changes of fatty aldehyde dehydrogenase( FALDH) were analyzed by Real-time polymerase chain reaction( PCR) analysis. The results showed that 4-HNE increased the release amount of LDH,lowered the cell viability of NCTC 1469 cells,and Tan Ⅱ_A reversed 4-HNE-induced hepatocyte damage. Western blot analysis and RT-PCR analysis results showed that 4-HNE decreased the expression of PPARα and FALDH and increased the expression of 4-HNE. However,the expression of PPARα and FALDH were increased significantly and the expression of 4-HNE was decreased obviously after Tan Ⅱ_A treatment. This study confirmed that the curative effect of Tan Ⅱ_A was obvious on hepatocytes damage,and the mechanism may be associated with activating PPARα and FALDH expression as well as scavenging 4-HNE.
Aldehyde Oxidoreductases ; metabolism ; Aldehydes ; Animals ; Cell Line ; Diterpenes, Abietane ; pharmacology ; Hepatocytes ; drug effects ; Lipid Peroxidation ; Mice ; Oxidative Stress ; PPAR alpha ; metabolism

This study aims to investigate the PPARγ agonists isolated from the aqueous extract of Siegesbeckia pubescens( SPA) and their anti-inflammatory activities in vitro. The 293 T cells transfected transiently with PPARγ recombinant plasmid were used as a screening model to guide the isolation of PPARγ activitating components,and then PPARγ activities were measured by double luciferase reporter gene assay. The chemical structures were identified by chromatography or spectroscopic techniques. Furthermore,a UC inflammatory model in vitro was established on HT-29 cells by stimulating with TNF-α． The mRNA levels and secretion of proinflammatory cytokines on HT-29 cells,such as IL-1β,TNF-α,IL-8,were detected by RT-PCR and ELISA. The results showed that five diterpenoids were obtained from the fraction D_(50) with the strongest PPARγ activity among others in SPA,and determined as kirenol( 1),darutigenol( 2),enantiomeric-2-ketone-15,16,19-three hydroxypinomane-8( 14)-ene-19-O-β-D-glucoside( 3),darutoside( 4),enantiomeric-2-β,15,16,19-four hydroxypinomane-8( 14)-ene-19-O-β-D-glucoside( 5),respectively. All the compounds exhibited active effects on PPARγ in a concentration-dependent manner( P<0. 01). In addition,compound 1 significantly inhibited the expression of IL-1β mRNA and secretion of IL-8 on HT-29 cells inflammation model( P<0. 001); both compounds 2 and 3 effectively inhibited the expression of IL-1β,TNF-α,IL-8 mRNA and secretion of IL-8( P<0. 01 or P<0. 001),although at different extent; compound 4 significantly inhibited the expression of IL-1β and TNF-α mRNA( P<0. 01 or P<0. 001),while compound 5 inhibited the expression of IL-1β mRNA obviously( P<0. 001). In conclusion,the diterpenoids 1-5 isolated from S. pubescens have the PPARγ activation activities and potential effects of anti-UC in vitro.
Anti-Inflammatory Agents/pharmacology* ; Asteraceae/chemistry* ; Colitis, Ulcerative ; Cytokines/immunology* ; Diterpenes/pharmacology* ; HT29 Cells ; Humans ; PPAR gamma/agonists* ; Tumor Necrosis Factor-alpha