Objective To investigate the effect of 15-Deoxy-△(12,14)-prostaglandin J2 (15 d-PGJ2) on the expression of macrophage migration inhibitory factor (MIF) and its underlying mechanism in J774A.1. Methods The murine monocyte/macrophage cell line J774A.1 were divided into six groups:lipopolysaccharide (LPS) group,incubated with 1 μg/ml LPS for 1 h;normal control group,incubated with PBS for 1 h;negative control group,incubated with 5 μmol/L 15 d-PGJ2 for 1 h;15 d-PGJ2 group,incubated with 5 μmol/L 15 d-PGJ2 for 1 h followed by 1 μg/ml LPS for 1 h;GW9662 group,incubated with 5 μmol/L 15 d-PGJ2 for 1 h following GW9662 10 μmol/L for 1 h,and then incubated with 1 μg/ml LPS for 1 h;and Vehicle group,control of GW9662,GW9662 was replaced by its solvent DMSO. The expression of MIF was detected via immunofluorescence and agarose gel electrophoresis. RT-qPCR and Western blotting were used to test whether 15 d-PGJ2 could regulate mRNA and protein expression of MIF in J774A.1 upon LPS challenge. The effect of peroxisome proliferator-activated receptor-γ (PPAR-γ) antagonist GW9662 on the regulation of MIF by 15 d-PGJ2 was observed. The effects of 15 d-PGJ2 on the nuclear translocation of PPAR-γ upon LPS challenge were detected via high content screening analysis. Results MIF DNA and protein expressions were detected in J774A.1. MIF mRNA expression was up-regulated (1.75±0.09,P=0.037) when challenged with LPS and 15 d-PGJ2 inhibited its upregulation (0.84±0.08,P=0.026) in J774A.1. The protein level was consistent with the mRNA level. PPAR-γ antagonist GW9662 reversed the effect of 15 d-PGJ2 (mRNA,1.48±0.06,P=0.016;protein,1.28). Furthermore,nuclear translocation of PPAR-γ was regulated by 15 d-PGJ2 in J774A.1 upon LPS challenge(1.39±0.02 vs. 1.01±0.03,P=0.003). Conclusion 15 d-PGJ2 may down-regulate the MIF expression in J774A.1 in a PPAR-γ-dependent manner.
Anilides ; pharmacology ; Animals ; Cell Line ; Intramolecular Oxidoreductases ; metabolism ; Lipopolysaccharides ; Macrophage Migration-Inhibitory Factors ; metabolism ; Mice ; Monocytes ; drug effects ; PPAR gamma ; antagonists & inhibitors ; Prostaglandin D2 ; analogs & derivatives ; pharmacology

OBJECTIVE: To investigate the effect of limb remote ischemic preconditioning (RIPC) on hepatic ischemia/reperfusion (IR) injury and the underlying mechanisms.
 METHODS: Rats were subjected to partial hepatic IR (60 min ischemia followed by 24 hours reperfusion) with or without RIPC, which was achieved by 3 cycles of 10 min-occlusion and 10 min-
reperfusion at the bilateral femoral arteries interval 30 min before ischemia. Some rats were treated with a new PPAR-γ inhibitor, T0070907, before RIPC.
 RESULTS: At the end of reperfusion, liver injury was significantly increased (increases in Suzike's injury score, AST and ALT release), concomitant with elevated oxidative stress (increases in MDA formation, MPO activity, as well as the decrease in SOD activity) and inflammation (increases in TNF-α and IL-6 levels, decrease in IL-10 content). RIPC improved liver function and reduced histologic damage, accompanied by the increased PPAR-γ activation and autophagosome formation as well as the reduced autophagosome clearance. The beneficial effects of RIPC were markedly attenuated by T0070907, an inhibitor of PPAR-γ.
 CONCLUSION RIPC exerts the protective effects on liver by activation of autophagy via PPAR-γ.
Animals ; Autophagy ; drug effects ; genetics ; physiology ; Extremities ; Interleukin-10 ; metabolism ; Interleukin-6 ; metabolism ; Ischemia ; Ischemic Preconditioning ; methods ; Liver ; injuries ; Liver Diseases ; prevention & control ; Oxidative Stress ; drug effects ; PPAR gamma ; antagonists & inhibitors ; Rats ; Reperfusion Injury ; prevention & control ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the effects of pioglitazone on transforming growth factor beta1 (TGFbeta1) expression in ischemia/reperfusion injury myocardium of rats.

METHODSThirty SD rats were randomly divided into five groups (n = 6): ischemia/reperfusion group, pioglitazone 5 mg/(kg x d) group, pioglitazone 10 mg/(kg x d) group, pioglitazone 20 mg/(kg x d) group and pioglitazone 20 mg/(kg x d) + peroxisome proliferator-activated receptor gamma (PPARgamma) specific antagonist GW9662 group. Left anterior descending coronary artery of rats were ligated for 30 min and reperfused for 120 min to establish the model of ischemia/reperfusion in vivo. RT-PCR was performed to detect the expression of TGFbeta1 mRNA. Western blot was performed to detect the expression of TGFbeta1 protein.

RESULTSMyocardial apoptosis was significantly suppressed by pioglitazone. Pioglitazone upregulated TGFPbeta1 expression both in mRNA and protein level. GW9662 reversed the inhibition of myocardial apoptosis and the upregulation of TGFbeta1 expression by pioglitazone.

CONCLUSIONPioglitazone can inhibit the myocardial apoptosis induced by ischemia/reperfusion. Pioglitazone may protect the myocardium from ischemia/reperfusion via upregulation of TGFbeta1. This protection may be mediated by PPARgamma.

Anilides ; pharmacology ; Animals ; Apoptosis ; Male ; Myocardial Reperfusion Injury ; metabolism ; Myocardium ; metabolism ; PPAR gamma ; antagonists & inhibitors ; Rats ; Rats, Sprague-Dawley ; Thiazolidinediones ; pharmacology ; Transforming Growth Factor beta1 ; metabolism

17β-estradiol (E2) treatment of cells results in an upregulation of SIRT1 and a down-regulation of PPARγ. The decrease in PPARγ expression is mediated by increased degradation of PPARγ. Here we report that PPARγ is ubiquitinated by HECT E3 ubiquitin ligase NEDD4-1 and degraded, along with PPARγ, in response to E2 stimulation. The PPARγ interacts with ubiquitin ligase NEDD4-1 through a conserved PPXY-WW binding motif. The WW3 domain in NEDD4-1 is critical for binding to PPARΓ. NEDD4-1 overexpression leads to PPARγ ubiquitination and reduced expression of PPARγ. Conversely, knockdown of NEDD4-1 by specific siRNAs abolishes PPARΓ ubiquitination. These data indicate that NEDD4-1 is the E3 ubiquitin ligase responsible for PPARγ ubiquitination. Here, we show that NEDD4-1 delays cellular senescence by degrading PPARΓ expression. Taken together, our data show that E2 could upregulate SIRT1 expression via promoting the PPARΓ ubiquitination-proteasome degradation pathway to delay the process of cell senescence.
Amino Acid Motifs ; Animals ; Cellular Senescence ; Down-Regulation ; drug effects ; Endosomal Sorting Complexes Required for Transport ; antagonists & inhibitors ; genetics ; metabolism ; Estradiol ; pharmacology ; Female ; HeLa Cells ; Humans ; Mice ; Mice, Inbred BALB C ; Nedd4 Ubiquitin Protein Ligases ; PPAR gamma ; genetics ; metabolism ; Proteasome Endopeptidase Complex ; metabolism ; Protein Structure, Tertiary ; RNA Interference ; RNA, Small Interfering ; metabolism ; Sirtuin 1 ; genetics ; metabolism ; Ubiquitin ; metabolism ; Ubiquitin-Protein Ligases ; antagonists & inhibitors ; genetics ; metabolism ; Ubiquitination ; drug effects ; Up-Regulation ; drug effects

OBJECTIVEThis study examined the effects of PI3K inhibitor LY294002 on the differentiation of mouse preadipocytes and the expression of CCAAT enhancer binding protein α (C/EBPα) and peroxisome proliferation activated receptor γ (PPARγ), in order to study the possible roles of insulin receptor substrate (IRSs)/PI3K signal pathway in the differentiation of preadipocytes.

METHODSThe mouse 3T3-L1 cells were cultured normally and divided into experimental and control groups. 3T3-L1 cells in the experimental group were treated with PI3K inhibitor LY294002 (25 μmol/L) and those in the control group were treated with DMSO culture medium. 3-isobutyl-1-methylxanthine (IBMX) (0.5 mmol/L), dexamethasone (10-6 mol/L) and insulin (5 μg/mL) were used to induce the differentiation of 3T3-L1 preadipocytes in both groups. Before culture, and 2, 4 and 8 days after culture, the cells were collected to detect the expression of C/EBPα and PPARγ by real-time PCR and Western blot assays. The lipid droplets of 3T3-L1 preadipocytes were observed by oil-red O staining.

RESULTSPI3K inhibitor LY294002 did not affect the expression of C/EBPα and PPAR&gamma; in un-induced 3T3-L1 preadipocytes (P>0.05), but decreased the expression of C/EBPα and PPAR&gamma; during the in vitro induced differentiation of 3T3-L1 preadipocytes compared with the control group (P<0.05 or 0.01). The lipid droplets count was greatly reduced by LY294002.

CONCLUSIONSPI3K inhibitor LY294002 can inhibit the differentiation of mouse 3T3-LI preadipocytes and the expression of C/EBPα and PPAR&gamma; in the differentiation of 3T3-LI preadipoeytes, suggesting that IRSs/PI3K signal pathway may play an important role in the differentiation of 3T3-L1 preadipocytes by regulating the expression of C/EBPα and PPAR&gamma;.

3T3-L1 Cells ; Adipocytes ; cytology ; drug effects ; Animals ; CCAAT-Enhancer-Binding Protein-alpha ; analysis ; genetics ; Cell Differentiation ; drug effects ; Chromones ; pharmacology ; Gene Expression Regulation ; drug effects ; Mice ; Morpholines ; pharmacology ; PPAR gamma ; analysis ; genetics ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; RNA, Messenger ; analysis

Lysimachia foenum-graecum has been used as an oriental medicine with anti-inflammatory effect. The anti-obesity effect of L. foenum-graecum extract (LFE) was first discovered in our screening of natural product extract library against adipogenesis. To characterize its anti-obesity effects and to evaluate its potential as an anti-obesity drug, we performed various obesity-related experiments in vitro and in vivo. In adipogenesis assay, LFE blocked the differentiation of 3T3-L1 preadipocyte in a dose-dependent manner with an IC50 of 2.5 microg/ml. In addition, LFE suppressed the expression of lipogenic genes, while increasing the expression of lipolytic genes in vitro at 10 microg/ml and in vivo at 100 mg/kg/day. The anti-adipogenic and anti-lipogenic effect of LFE seems to be mediated by the inhibition of PPARgamma and C/EBPalpha expression as shown in in vitro and in vivo, and the suppression of PPARgamma activity in vitro. Moreover, LFE stimulated fatty acid oxidation in an AMPK-dependent manner. In high-fat diet (HFD)-induced obese mice (n = 8/group), oral administration of LFE at 30, 100, and 300 mg/kg/day decreased total body weight gain significantly in all doses tested. No difference in food intake was observed between vehicle- and LFE-treated HFD mice. The weight of white adipose tissues including abdominal subcutaneous, epididymal, and perirenal adipose tissue was reduced markedly in LFE-treated HFD mice in a dose-dependent manner. Treatment of LFE also greatly improved serum levels of obesity-related biomarkers such as glucose, triglycerides, and adipocytokines leptin, adiponectin, and resistin. All together, these results showed anti-obesity effects of LFE on adipogenesis and lipid metabolism in vitro and in vivo and raised a possibility of developing LFE as anti-obesity therapeutics.
3T3-L1 Cells ; Adipogenesis/*drug effects ; Adipose Tissue/drug effects/metabolism ; Adipose Tissue, White ; Animals ; Anti-Obesity Agents/administration & dosage/pharmacology/*therapeutic use ; Body Weight/drug effects ; CCAAT-Enhancer-Binding Protein-alpha/genetics ; Cell Differentiation/drug effects ; Eating/drug effects ; Fatty Acids/metabolism ; Gene Expression/drug effects ; Lipid Metabolism/*drug effects ; Lipids ; Lipogenesis/drug effects ; Mice ; Mice, Inbred C57BL ; Obesity/prevention & control ; PPAR gamma/antagonists & inhibitors/genetics ; Plant Extracts/*pharmacology ; Plants, Medicinal ; Primulaceae/*chemistry

PURPOSE: Imbalances between osteogenic and adipogenic differentiation leads to diseases such as osteoporosis. The aim of our study was to demonstrate the differences in extracellular signal-regulated kinase (ERK) phosphorylation during both adipogenesis and osteogenesis of human bone marrow-derived stem cells (BMSCs). MATERIALS AND METHODS: Using troglitazone, GW9662 and U0126, we investigated their role in hBMSC differentiation to adipogenic and osteogenic fates. RESULTS: ERK1/2 inhibition by U0126 suppressed proliferator-activated receptor (PPAR)gamma expression and lipid accumulation, while it decreased the mRNA expression of adipogenic genes (lipoprotein lipase, PPARgamma, and adipocyte protein) and osteogenic genes (type I collagen and osteopontin). ERK phosphorylation was transient and decreased during adipogenesis, whereas it occurred steadily during osteogenesis. Troglitazone, a PPARgamma agonist, induced adipogenesis by inhibiting ERK phosphorylation even in an osteogenic medium, suggesting that ERK signaling needs to be shut off in order to proceed with adipose cell commitment. Cell proliferation was greatly increased in osteogenesis but was not changed during adipogenesis, indicating that ERK might play different roles in cellular proliferation and differentiation between the two committed cell types. CONCLUSION: The duration and magnitude of ERK activation might be a crucial factor for the balance between adipogenesis and osteogenesis in human bone marrow-derived stem cells.
Adipogenesis/*drug effects/genetics ; Adult ; Anilides/pharmacology ; Bone Marrow Cells/*cytology/drug effects/metabolism ; Butadienes/pharmacology ; Cell Differentiation/drug effects ; Cells, Cultured ; Chromans/pharmacology ; Extracellular Signal-Regulated MAP Kinases/*metabolism ; Female ; Humans ; Male ; Middle Aged ; Nitriles/pharmacology ; Osteogenesis/*drug effects/genetics ; PPAR gamma/agonists/antagonists & inhibitors ; Phosphorylation/drug effects ; Reverse Transcriptase Polymerase Chain Reaction ; Stem Cells/*cytology/drug effects/*metabolism ; Thiazolidinediones/pharmacology

PURPOSE: Imbalances between osteogenic and adipogenic differentiation leads to diseases such as osteoporosis. The aim of our study was to demonstrate the differences in extracellular signal-regulated kinase (ERK) phosphorylation during both adipogenesis and osteogenesis of human bone marrow-derived stem cells (BMSCs). MATERIALS AND METHODS: Using troglitazone, GW9662 and U0126, we investigated their role in hBMSC differentiation to adipogenic and osteogenic fates. RESULTS: ERK1/2 inhibition by U0126 suppressed proliferator-activated receptor (PPAR)gamma expression and lipid accumulation, while it decreased the mRNA expression of adipogenic genes (lipoprotein lipase, PPARgamma, and adipocyte protein) and osteogenic genes (type I collagen and osteopontin). ERK phosphorylation was transient and decreased during adipogenesis, whereas it occurred steadily during osteogenesis. Troglitazone, a PPARgamma agonist, induced adipogenesis by inhibiting ERK phosphorylation even in an osteogenic medium, suggesting that ERK signaling needs to be shut off in order to proceed with adipose cell commitment. Cell proliferation was greatly increased in osteogenesis but was not changed during adipogenesis, indicating that ERK might play different roles in cellular proliferation and differentiation between the two committed cell types. CONCLUSION: The duration and magnitude of ERK activation might be a crucial factor for the balance between adipogenesis and osteogenesis in human bone marrow-derived stem cells.
Adipogenesis/*drug effects/genetics ; Adult ; Anilides/pharmacology ; Bone Marrow Cells/*cytology/drug effects/metabolism ; Butadienes/pharmacology ; Cell Differentiation/drug effects ; Cells, Cultured ; Chromans/pharmacology ; Extracellular Signal-Regulated MAP Kinases/*metabolism ; Female ; Humans ; Male ; Middle Aged ; Nitriles/pharmacology ; Osteogenesis/*drug effects/genetics ; PPAR gamma/agonists/antagonists & inhibitors ; Phosphorylation/drug effects ; Reverse Transcriptase Polymerase Chain Reaction ; Stem Cells/*cytology/drug effects/*metabolism ; Thiazolidinediones/pharmacology

TGFβ/smad pathway is recognized as an important signal pathway to promote the pathogenesis of atherosclerosis (AS). Peroxisome proliferator-activated receptor &gamma; (PPAR&gamma;) activation is considered to be important in modulating AS. Herein, we investigated the regulation of PPAR&gamma; on c-Ski, the repressor of TGFβ/smad pathway, in rat AS model and cultured vascular smooth muscle cells (VSMCs). c-Ski mRNA and protein expression were detected by real-time PCR and Western blot, respectively, in vivo and in vitro with treatment of PPAR&gamma; agonist rosiglitazone and antagonist GW9662. The proliferation and collagen secretion of VSMCs after c-Ski transfection were investigated. The underlying mechanism was further investigated by online program NUBIScan and luciferase reporter gene analysis. Results showed that both mRNA and protein expressions of c-Ski in the AS lesions was down-regulated in vivo, while in cultured VSMCs, c-Ski transfection significantly suppressed the proliferation and collagen secretion of rat VSMCs. Rosiglitazone significantly up-regulated mRNA and protein levels of c-Ski in VSMCs, which could be blocked by GW9662. Online NUBIScan analysis suggested possible PPAR&gamma; binding sites in the promoter region of c-Ski. In addition, luciferase activity of c-Ski reporter gene was also increased obviously in the presence of rosiglitazone. These results indicate that c-Ski is one of the newly found target genes of PPAR&gamma; and thus involved in the anti-AS effect of PPAR&gamma;.
Anilides ; pharmacology ; Animals ; Atherosclerosis ; physiopathology ; Cells, Cultured ; Male ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; metabolism ; PPAR gamma ; agonists ; antagonists & inhibitors ; physiology ; Proto-Oncogene Proteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Repressor Proteins ; genetics ; metabolism ; Signal Transduction ; Smad Proteins ; metabolism ; Thiazolidinediones ; pharmacology ; Transforming Growth Factor beta ; metabolism ; Up-Regulation

BACKGROUND/AIMS: Ligands for peroxisome proliferator-activated receptor gamma (PPAR gamma), a member of the ligand-activated nuclear receptor superfamily, exhibit anti-tumoral effects and are associated with de novo synthesis of proteins involved in regulating the cell cycle and cell survival/death. Helicobacter pylori (H. pylori) is an etiologic agent for gastric adenocarcinoma, and raises the cell turnover of gastric epithelium. The aim of this study was to investigate the effect of PPAR gamma ligand rosiglitazone on the cell proliferation and the expressions of p27 and Skp2 protein in H. pylori infected gastric epithelial cells. METHODS: We examined the expression of PPAR gamma by Western blot in H. pylori infected AGS human gastric epithelial cells. The effect of rosiglitazone on the survival of H. pylori infected AGS cells was assessed by cell viability assay. After the treatment of rosiglitazone in H. pylori infected AGS cells, the expressions of p27 and Skp2 were assessed by Western blot. RESULTS: The expression of PPAR gamma protein was increased in H. pylori infected AGS cells. Cell growth was inhibited and decreased in dose- and time- dependent manner in H. pylori infected AGS cells treated with rosiglitazone. A decrease in Skp2 expression and a reciprocal increase in p27 expression were found in dose- and time-dependent manner in H. pylori infected AGS cells treated with rosiglitazone. CONCLUSIONS: Rosiglitazone inhibited the growth of H. pylori infected AGS cells. Rosiglitazone attenuated Skp2 expression, thereby promoting p27 accumulation in H. pylori infected human gastric epithelial cells. Further studies will be needed to find the effects of accumulation on cell turnover in H. pylori infection and the role in the H. pylori-associated gastric carcinogenesis.
Anti-Bacterial Agents/*pharmacology ; Cell Line ; Cell Proliferation ; Cyclin-Dependent Kinase Inhibitor p27/*metabolism ; Epithelial Cells/metabolism/*microbiology ; Gastric Mucosa/cytology/metabolism/*microbiology ; *Helicobacter pylori ; Humans ; PPAR gamma/antagonists &inhibitors/metabolism ; S-Phase Kinase-Associated Proteins/*metabolism ; Thiazolidinediones/*pharmacology