OBJECTIVETo investigate the changes of NF-kappa B binding activity, the expression of PPARr and their correlation in the liver of rats with fatty liver disease (FLD) induced by different pathogenic factors and to investigate the molecular mechanism of the inflammation in FLD.

METHODS40 Wistar rats were randomly divided into 4 groups of ten each: normal group, alcohol group, fat-rich diet group, alcohol adding fat-rich diet group. The rats were sacrificed at the end of the 16th week from the starting day of the experiment. Serum and liver specimens were collected. Histological specimens were stained with HE, SudanIV, and Masson and then studied microscopically. The ultrastructural changes were also checked under an electron microscope. NF-kappa B binding activity and the expression of PPARr mRNA were determined by electrophoretic mobility shift assay (EMSA) and RT-PCR respectively. The correlations between NF-kappa B binding activity and the expression of PPARr and the biochemical indexes were analyzed.

RESULTSSteatosis, inflammation, necrosis and fibrosis were present in livers of the rats of all the experimental groups, and were most severe in the alcohol adding fat-rich diet group. NF-kappa B binding activity was markedly increased in the livers of the alcohol group (142+/-16.32) and of the alcohol adding fat-rich diet group (238+/-19.14) in comparison to the livers of the normal (73+/-9.24, F = 6.36, 17.93) and those of the fat-rich diet group (84+/-10.38, F = 5.96, 16.20). Binding activity was higher in the alcohol adding fat-rich diet group than that in the simple alcohol group, but there was no difference between those of the fat-rich diet and normal groups. The level of PPARr mRNA was lower in the livers of the alcohol, fat-rich diet, alcohol adding fat-rich diet groups (0.2530+/-0.069, 0.3647+/-0.082, 0.1226+/-0.054) than that of the controls (0.8097+/-0.094) (F = 15.43, 7.24, 21.45). NF-kappa B binding activity was correlated positively with the level of serum TNF alpha (r = 0.527, 0.639) and the content of MDA in the liver homogenates (r = 0.723, 0.537), but negatively with the expression of PPARr in the livers of the alcohol and the alcohol adding fat-rich diet groups (r = -0.568, -0.891).

CONCLUSIONThe enhanced nuclear factors NF-kappa B binding activity and decreased expression of PPARr play a pivotal role in the inflammatory response of FLD induced by alcohol and fat-rich diet. It may provide a new idea for treating FLD effectively.

Animals ; Fatty Liver ; metabolism ; Liver ; metabolism ; Male ; NF-kappa B ; metabolism ; PPAR gamma ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar

Swine is an ideal model for diabetes studies. Insulin and insulin resistance are closely related with diabetes. To investigate the effect of SOCS-3 in insulin resistance, porcine primary adipocyte was treated with insulin (100 nmol/L) and dexamethasone (300 nmol/L) to induce insulin resistance. The simi-quantitative PCR results suggested that insulin increased GLUT4, PPARgamma and SOCS-3 gene expression in primary culture porcine adipocytes and no change of OB gene expression. Under insulin resistance conditions, SOCS-3 and OB gene expression were up-regulated, whereas GLUT4 and PPARgamma gene expression were down-regulated in primary porcine adipocytes. The overexpression of PPARgamma gene resulted in the increase of GLUT4 expression by insulin. Different expression levels of SOCS-3 determined the inhibitory effects of insulin signaling. Induction of insulin resistance by dexamethasone was not only due to inhibition of glucose transportation, but also repression of insulin signaling. SOCS-3 might be a potential gene to block the insulin resistance.
Adipocytes ; cytology ; metabolism ; Animals ; Cells, Cultured ; Dexamethasone ; pharmacology ; Glucose Transporter Type 4 ; biosynthesis ; genetics ; Insulin ; pharmacology ; Insulin Resistance ; Leptin ; biosynthesis ; genetics ; PPAR gamma ; biosynthesis ; genetics ; Suppressor of Cytokine Signaling 3 Protein ; Suppressor of Cytokine Signaling Proteins ; biosynthesis ; genetics ; Swine

Animals ; Cells, Cultured ; Cyclosporine ; antagonists & inhibitors ; Fibronectins ; biosynthesis ; genetics ; Hepatocytes ; cytology ; drug effects ; PPAR gamma ; biosynthesis ; genetics ; Protective Agents ; pharmacology ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Thiazolidinediones ; pharmacology ; Transforming Growth Factor beta1 ; biosynthesis ; genetics

To investigate the expression patterns of peroxisome proliferator activated receptor2 (PPARgamma2) gene in the differentiation of mouse embryonic stem (ES) cells into adipocytes, mouse ES cells were transfected with the vector of pPPARgamma2-promoter-luciferase, and PPARgamma2 expressions were analyzed by detecting luciferase activities and by detecting the protein expressions using western blotting. The results showed that the gene PPARgamma2 did not express in undifferentiated mouse ES cells and in embryoid bodies (EBs) within the first 2 days of differentiation induction after EB formation, and began to express from the third day of differentiation induction after EB formation to the finish of the differentiation. The gene's expression in differentiated adipocytes was much stronger than that in differentiating preadipocytes. In Conclusion our results reported for the first time the five-step expression patterns of the gene PPARgamma2 during the whole differentiation procedures from mouse ES cells into adipocytes via preadipocytes, and supported the previous studies that PPARgamma2 is a fat-specific gene that expresses only in developed and developing adipose tissues.
Adipocytes ; cytology ; Animals ; Cell Differentiation ; genetics ; Cells, Cultured ; Electroporation ; Embryonic Stem Cells ; cytology ; metabolism ; Mice ; PPAR gamma ; biosynthesis ; genetics ; Promoter Regions, Genetic ; genetics ; Transfection

OBJECTIVETo investigate the expression and significance of peroxisome proliferators-activated receptor gamma (PPAR gamma) in human glioma.

METHODSImmunohistochemical staining for PPAR gamma was performed using biopsy specimens of human glioma of various histological types. Expression of PPAR gamma and GFAP in glioma cell lines SWO-38, U251 and SHG-44 were analyzed using Western blotting and reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSImmunohistochemical study showed that PPAR gamma was expressed in glioma tissues with positive rate of 37.5%. Western blotting and RT-PCR showed that PPAR gamma was expressed in both glioma cell lines SWO-38 and U251, but not in SHG-44 cells. However, high expression of GFAP was detected in SHG-44 cells.

CONCLUSIONPPAR gamma is associated with carcinogens of glioma. Actived PPAR gamma by agonist may be a novel approach to the treatment of glioma.

Blotting, Western ; Brain Neoplasms ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Glial Fibrillary Acidic Protein ; biosynthesis ; genetics ; Glioma ; genetics ; metabolism ; pathology ; Humans ; Immunohistochemistry ; PPAR gamma ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo study the effect of conjugated linoleic acid (CLA) on expression of adiponectin in white adipose tissue of obese rats.

METHODSMale Wistar rats were randomly divided into control group, high-fat group and high fat + CLA group (0.75 g, 1.50 g, 3.00 g per hundred gram diet weight), we observed the effect of CLA on serum insulin and glucose levels of obese rats, and the reverse transcription polymerase chain reaction (RT-PCR) technique was used to measure the expression level of adiponectin and peroxisome proliferator-activated receptor-gamma (PPARgamma) mRNA.

RESULTSThe serum insulin and glucose levels of obese rats were (11.11 +/- 2.73) microIU/ml, (5.09 +/- 0.66) mmol/L. The supplement of CLA decreased the hyperinsulinemia and hyperglycemia, the serum insulin in CLA group (0.75 g, 1.50 g, 3.00 g per hundred gram diet weight) were (6.99 +/- 1.77) microIU/ml, (7.36 +/- 1.48) microIU/ml, (7.85 +/- 1.60) microIU/ml (P < 0.05), and glucose were (4.28 +/- 0.72) mmol/L, (4.18 +/- 0.55) mmol/L (P < 0.05), (4.06 +/- 0.63) mmol/L (P < 0.05), CLA can increase the expression of adiponectin and PPARgamma in adipose tissue of obese rat.

CONCLUSIONThe CLA might improve the insulin resistance of the obese rat and increase the expression of adiponectin mRNA, which might possibly act through activating PPARgamma.

Adiponectin ; biosynthesis ; genetics ; Adipose Tissue ; metabolism ; Animals ; Insulin Resistance ; physiology ; Linoleic Acids, Conjugated ; pharmacology ; Male ; Obesity ; metabolism ; PPAR gamma ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction

Animals ; Antineoplastic Agents ; therapeutic use ; Chromans ; therapeutic use ; Diethylnitrosamine ; Ligands ; Liver Neoplasms, Experimental ; chemically induced ; drug therapy ; Male ; PPAR gamma ; biosynthesis ; genetics ; Rats ; Rats, Wistar ; Thiazolidinediones ; therapeutic use

OBJECTIVETo investigate the effect of peroxisome proliferator-activated receptor-alpha (PPAR alpha) and PPAR gamma activators on tumor necrosis factor-alpha (TNFalpha) expression in neonatal rat cardiac myocytes.

METHODSPrimary cultures of cardiac myocytes from 1- to 3-day-old Wistar rats were prepared, and myocytes were exposed to lipopolysaccharide (LPS) and varying concentrations of PPAR alpha or PPAR gamma activator (fenofibrate or pioglitazone). RT-PCR and ELISA were used to measure TNFalpha, PPAR alpha, and PPAR gamma expression in cultured cardiac myocytes. Transient transfection of TNFalpha promoter with or without nuclear factor-kappaB (NF-kappaB) binding site to cardiac myocytes was performed.

RESULTSPretreatment of cardiac myocytes with fenofibrate or pioglitazone inhibited LPS-induced TNFalpha mRNA and protein expression in a dose-dependent manner. However, no significant changes were observed on PPAR alpha or PPAR gamma mRNA expression when cardiac myocytes were pretreated with fenofibrate or pioglitazone. Proportional suppression of TNFalpha promoter activity was observed when myocytes was transiently transfected with whole length of TNFalpha promoter (-721/+17) after being stimulated with LPS and fenofibrate or pioglitazone, whereas no change of promoter activity was observed with transfection of TNFalpha reporter construct in deletion of NF-kappaB binding site (-182/+17).

CONCLUSIONSPPAR alpha and PPAR gamma activators may inhibit cardiac TNFalpha expression but not accompanied by change of PPAR alpha or PPAR gamma mRNA expression. Therefore PPAR alpha and PPAR gamma activators appear to play a role in anti-inflammation. The mechanism may partly be involved in suppression of the NF-kappaB pathway.

Animals ; Animals, Newborn ; Cells, Cultured ; Dose-Response Relationship, Drug ; Fenofibrate ; pharmacology ; Lipopolysaccharides ; pharmacology ; Myocytes, Cardiac ; metabolism ; NF-kappa B ; metabolism ; PPAR alpha ; biosynthesis ; genetics ; PPAR gamma ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Wistar ; Thiazolidinediones ; pharmacology ; Tumor Necrosis Factor-alpha ; biosynthesis ; genetics

In the present study, we show that the expression of type 2 glucose transporter isoform (GLUT2) could be regulated by PPAR-gamma in the liver. Rosiglitazone, PPAR-gamma agonist, activated the GLUT2 mRNA level in the primary cultured hepatocytes and Alexander cells, when these cells were transfected with PPAR-gamma/RXR-alpha. We have localized the peroxisome proliferator response element in the mouse GLUT2 promoter by serial deletion studies and site-directed mutagenesis. Chromatin immunoprecipitation assay using ob/ob mice also showed that PPAR-gamma rather than PPAR-alpha binds to the -197/-184 region of GLUT2 promoter. Taken together, liver GLUT2 may be a direct target of PPAR-gamma ligand contributing to glucose transport into liver in a condition when PAPR-gamma expression is increased as in type 2 diabetes or in severe obesity.
Animals ; Cells, Cultured ; Chromatin Immunoprecipitation ; Gene Expression Regulation ; Genes, Reporter ; Hepatocytes/*metabolism ; Liver/metabolism ; Male ; Mice ; Mice, Inbred ICR ; Mice, Transgenic ; Monosaccharide Transport Proteins/*biosynthesis/genetics ; Mutagenesis, Site-Directed ; PPAR alpha/genetics/metabolism ; PPAR gamma/agonists/genetics/*metabolism ; *Promoter Regions (Genetics) ; Protein Isoforms/biosynthesis ; Research Support, Non-U.S. Gov't ; *Response Elements ; Thiazolidinediones/pharmacology

PURPOSE: We recently reported that rosiglitazone (RGTZ), a peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, has a protective effect against cyclosporine (CsA)- induced renal injury. Here we report the effect of RGTZ on peroxisome proliferator-activated receptor gamma (PPARgamma) expression in an experimental model of chronic cyclosporine (CsA) nephropathy. MATERIALS AND METHODS: Chronic CsA nephropathy was induced in Sprague-Dawley rats by administering CsA (15mg/kg per day) for 28 days, and control rats were treated with vehicle (VH group, olive oil 1mL/kg per day) for 28 days. RGTZ (3mg/kg) was concurrently administered via gavage to the CsA and VH groups. Expression of PPARgamma mRNA and protein was evaluated with RT-PCR, immunohistochemistry, and immunoblotting. RESULTS: PPARgamma mRNA expression was similar to the level of PPARgamma protein constitutively expressed in the kidneys of the VH treated rats, with expression in the glomerular epithelial, distal tubular cells, and collecting tubular cells. PPARgamma protein expression in CsA-treated rat kidneys was significantly less than in the VH group. However, concomitant administration of RGTZ restored PPARgamma protein expression in the kidneys of the CsA- reated rats. CONCLUSION: Exogenous administration of RGTZ treatment upregulates PPARgamma expression and that this mechanism may play a role in protecting against CsA-induced renal injury.
Transcription, Genetic/*drug effects ; Thiazolidinediones/*pharmacology ; Rats, Sprague-Dawley ; Rats ; RNA, Messenger/*genetics ; Protein Biosynthesis/*drug effects ; PPAR gamma/*genetics ; Male ; Kidney Diseases/genetics/pathology/*prevention & control ; Gene Expression Regulation/*drug effects ; Disease Models, Animal ; Cyclosporine/*toxicity ; Animals