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

Obesity is associated with a number of metabolic abnormalities such as type 2 diabetes and has become a major health problem worldwide. In the present study, we investigated the effects of Epimedium koreanum Nakai (Herba Epimedii, HE) and its main constituent icariin on the adipocyte differentiation in 3T3-L1 preadipocytes. HE extract and icariin significantly reduced lipid accumulation and suppressed the expressions of PPARγ, C/EBPα, and SREBP-1c in 3T3-L1 adipocytes. They also inhibited fatty acid synthase (FAS), acyl-Co A synthase (ACS1), and perilipin. Moreover, HE extract and icariin markedly increased the phosphorylation of AMPK. These results indicated that HE extract and icariin can inhibit the adipocyte differentiation through downregulation of the adipogenic transcription factors, suggesting that HE containing icariin may be used as a potential therapeutic agent in the treatment and prevention of obesity.
3T3-L1 Cells ; Adipocytes ; cytology ; drug effects ; metabolism ; Adipogenesis ; drug effects ; Animals ; CCAAT-Enhancer-Binding Protein-alpha ; genetics ; metabolism ; Epimedium ; chemistry ; Flavonoids ; pharmacology ; Lipid Metabolism ; drug effects ; Mice ; PPAR gamma ; genetics ; metabolism ; Plant Extracts ; pharmacology ; Sterol Regulatory Element Binding Protein 1 ; genetics ; metabolism

OBJECTIVETo investigate the effect of peroxisiome proliferator activated receptor-&alpha; (PPAR-&alpha;) on the regulation of cardiomyocyte hypertrophy and the relationship between the effect of PPAR-&alpha; with PI3K/Akt//mTOR signal pathway.

METHODSCardiomyocyte hypertrophy was induced by isoproterenol (ISO). The cell surface area was measured by image analysis system (Leica). The expressions of atrial natriuretic peptide (ANP), β-myosin heavy chain (β-MHC) and PPAR-&alpha; mRNA were detected by qRT-PCR. The protein expressions of Akt, mTOR and P70S6K were detected by Western blot. The expression of PPAR-&alpha; was suppressed by RNAi.

RESULTS(1) The expression of PPAR-&alpha; was significantly reduced in cardiomyocyte hypertrophy. PPAR-&alpha; activator Fenofibrate (Feno) increased the expression of PPAR-&alpha; and suppressed cardiomyocyte hypertrophy. The inhibitory effect of Feno on cardiomyocyte hypertrophy was reversed by PPAR-&alpha; RNAi. (2) Feno significantly inhibited the increase of the protein expressions of p-Akt, p-mTOR and p-p70S6K in ISO induced cardiomyocyte hypertrophy, which could be blocked by PPAR-&alpha; RNAi. (3) PI3K antagonist LY294002 (LY) or mTOR antagonist rapamycin (RAPA) markedly-inhibited cardiomyocyte hypertrophy. The inhibitory effects of LY or RAPA on cardiomyocyte hypertrophy were reversed by PPAR-&alpha; RNAi.

CONCLUSIONPPAR-&alpha; can negatively regulate cardiomyocyte hypertrophy. The effect might be associated with PPAR-&alpha; inhiting PI3K/ Akt/mTOR signal pathway.

Atrial Natriuretic Factor ; metabolism ; Cardiomegaly ; metabolism ; Cells, Cultured ; Fenofibrate ; pharmacology ; Humans ; Isoproterenol ; adverse effects ; Myocytes, Cardiac ; drug effects ; metabolism ; Myosin Heavy Chains ; metabolism ; PPAR alpha ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; RNA, Messenger ; Ribosomal Protein S6 Kinases, 70-kDa ; metabolism ; Signal Transduction ; TOR Serine-Threonine Kinases ; metabolism

OBJECTIVETo investigate the effect of apigenin on the protein expression levels of peroxisome proliferator-activated receptors (PPARs) in liver tissues of rats with nonalcoholic steatohepatitis (NASH).

METHODSThe NASH rat model was established by feeding of a high-fat diet. Unmodeled rats served as the normal controls. The modeled rats were divided into a model control group, Essentiale treatment grouP(300 mg/kg/day),and three apigenin treatment groups for low-dose (15 mg/kg/day), moderate-dose (30 mg/kg/day) and high-dose (60 mg/kg/day). After 13 weeks of treatment,changes in insulin sensitivity from pre-treatment baseline were assessed by measuring the alanine aminotransferase (ALT), aspartate aminotransferase (AST),total cholesterol (TC),triglycerides (TG),low-density and high-density lipoprotein cholesterol (LDL-C and HDL-C),fasting blood glucose (FBG) and fasting insulin (FINS).The liver index and HOMA-IR were also calculated.Protein and gene expression of PPAR&alpha; and PPARgamma in liver tissue were assessed by immunohistochemistry and RT-PCR.Statistical analysis was performed by the LSD test and Games-Howell test.

RESULTSThe apigenin-treated groups showed a significantly greater change in insulin sensitivity than the untreated model group,with the most significant change occurring in the high-dose grouP(P less than 0.05).Compared with the untreated model group,the apigenin-treated groups showed lower levels of ALT (95.4+/-7.3),AST (183.7+/-14.3),TC (1.61+/-0.25),TG (1.23+/-0.21),LDL-C (1.86+/-0.14),FBG (5.29+/-1.45) and FINS (0.76+/-0.86),but a higher level of HDL-C (1.04+/-0.17); again,the high-dose group showed the greatest change (all P less than 0.05).Compared to the untreated model group,the apigenin-treated groups showed significantly lower liver index (3.75+/-0.25 vs.2.90+/-0.17) and HOMA-IR (1.34+/-0.06 vs.0.18+/-0.04),with the high-dose group showing the greatest change (both P less than 0.05). Compared to the untreated model group,the apigenin-treated groups showed higher levels of protein and mRNA of PPAR&alpha; (18.27+/-4.05 and 0.63+/-0.02,respectively) and PPARgamma(8.48+/-5.05 and 0.39+/-0.02),with the high-dose group showing the greatest change (all P < 0.05).

CONCLUSIONApigenin can improve glucose tolerance,lipid metabolism and insulin resistance while decreasing blood levels of TC,TG,LDL-C,FBG,FINS and HOMA-IR,and increasing HDL-C in NASH,as shown in a high-fat diet induced rat model, and may have therapeutic potential.

Alanine Transaminase ; metabolism ; Animals ; Apigenin ; pharmacology ; Aspartate Aminotransferases ; metabolism ; Blood Glucose ; metabolism ; Cholesterol ; metabolism ; Disease Models, Animal ; Insulin ; metabolism ; Insulin Resistance ; Lipid Metabolism ; Liver ; enzymology ; Non-alcoholic Fatty Liver Disease ; metabolism ; PPAR alpha ; metabolism ; PPAR gamma ; metabolism ; Peroxisome Proliferator-Activated Receptors ; metabolism ; Rats ; Rats, Sprague-Dawley ; Triglycerides ; metabolism