Parathyroid hormone-related protein (PTHrP) is synthesized by diverse tissues, and its processing produces several fragments, each with apparently distinct autocrine and paracrine bioactivities. In bone, PTHrP appears to modulate bone formation in part through promoting osteoblast differentiation. The putative effect of PTH-like and PTH-unrelated fragments of PTHrP on human mesenchymal stem cell (MSCs) is not well known. Human MSCs were treated with PTHrP (1-36) or PTHrP (107-139) or both (each at 10 nM) in osteogenic or adipogenic medium, from the start or after 6 days of exposure to the corresponding medium, and the expression of several osteoblastogenic and adipogenic markers was analyzed. PTHrP (1-36) inhibited adipogenesis in MSCs and favoured the expression of osteogenic early markers. The opposite was observed with treatment of MSCs with PTHrP (107-139). Moreover, inhibition of the adipogenic differentiation by PTHrP (1-36) prevailed in the presence of PTHrP (107-139). The PTH/PTHrP type 1 receptor (PTH1R) gene expression was maximum in the earlier and later stages of osteogenesis and adipogenesis, respectively. While PTHrP (107-139) did not modify the PTH1R overexpression during adipogenesis, PTHrP (1-36) did inhibit it; an effect which was partially affected by PTHrP (7-34), a PTH1R antagonist, at 1 microM. These findings demonstrate that both PTHrP domains can exert varying effects on human MSCs differentiation. PTHrP (107-139) showed a tendency to favor adipogenesis, while PTHrP (1-36) induced a mild osteogenic effect in these cells, and inhibited their adipocytic commitment. This further supports the potential anabolic action of the latter peptide in humans.
Adipogenesis/drug effects ; Alkaline Phosphatase/biosynthesis/genetics ; Antigens, Differentiation/biosynthesis/genetics ; Bone Marrow/pathology ; Cell Differentiation/drug effects ; Cells, Cultured ; Core Binding Factor Alpha 1 Subunit/biosynthesis/genetics ; Culture Media ; Gene Expression Regulation ; Humans ; Lipoprotein Lipase/biosynthesis/genetics ; Mesenchymal Stem Cells/*drug effects/metabolism/pathology ; Osteoblasts/drug effects/*metabolism/pathology ; Osteogenesis/drug effects ; PPAR gamma/biosynthesis/genetics ; Parathyroid Hormone/*pharmacology ; Peptide Fragments/*pharmacology ; Receptor, Parathyroid Hormone, Type 1/antagonists & inhibitors

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

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

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

OBJECTIVE: To investigate the effect of the peroxisome proliferator activated receptor-gamma (PPAR-gamma) agonist troglitazone on TGF-beta(1) and fibronectin (Fn) expression in human peritoneal mesothelial cells (HPMCs). METHODS: HPMCs were cultured from human omentum by an enzyme digestion method, growing in medium containing 30 mmol/L D-glucose. TGF-beta(1) and Fn expression were measured in HPMCs in the presence and absence of 15 micromol/L troglitazone. The mRNA expressions of PPAR-gamma,TGF-beta(1) and Fn were determined by semi-quantification reverse transcriptive PCR (RT-PCR). The protein of TGF-beta(1) was determined by enzyme-linked immunosorbent assay (ELISA) and proteins of PPAR-gamma and Fn were determined by Western blot. RESULTS: The mRNA and protein expression of TGF-beta(1) and Fn were significantly increased in HPMCs stimulated with 30 mmol/L D-glucose compared with the control group with F12 media (P<0.01). Obvious decrease of TGF-beta(1) was found in troglitazone(15 micromol/L) treated group compared with group stimulated with 30 mmol/L D-glucose (P<0.05). Exposure of HPMCs to troglitazone reduced the Fn secretion (P<0.05). CONCLUSION Troglitazone reduced the expression of TGF-beta(1) in HPMCs stimulated by 30mmol/L D-glucose, and reduced Fn production. PPAR-gamma agonists may have a specific role in ameliorating the course of progressive peritoneal fibrosis under long-term peritoneal dialysis states.
Blotting, Western ; Cells, Cultured ; Chromans ; pharmacology ; Dose-Response Relationship, Drug ; Enzyme-Linked Immunosorbent Assay ; Epithelial Cells ; cytology ; drug effects ; metabolism ; Fibronectins ; biosynthesis ; genetics ; Glucose ; pharmacology ; Humans ; PPAR gamma ; biosynthesis ; genetics ; Peritoneum ; cytology ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Thiazolidinediones ; pharmacology ; Transforming Growth Factor beta1 ; biosynthesis ; genetics ; Troglitazone

AIMTo investigate the effect of resveratrol on EMMPRIN expression of macrophages.

METHODSHuman monocytic cell line THP-1 cells were co-cultured with EMMPRIN-highly-expressed MCF-7 cells; MMP-9 production was assayed by zymography. THP-1 cells were induced by PMA, expression of EMMPRIN was assayed by Western blotting. Cells were treated with resveratrol or PPARgamma agonist--pioglitazone during differentiation, EMMPRIN expression and MMP-9 activity were assayed. U937 cells were co-transfected with PPARy expression and luciferase-coding reporter vector, then cultured with pioglitazone or resveratrol, the activating capability of resveratrol on PPARgamma was evaluated by measuring the luciferase activity. THP-1 cells were pretreated with PPARgamma antagonist--GW9662 before pioglitazone or resveratrol treatment, then assayed for EMMPRIN expression and MMP-9 production.

RESULTSEMMPRIN expression was greatly increased during the differentiation from monocytes to macrophages; co-culturing with MCF-7 cells significantly increased MMP-9 production by monocytes. Both resveratrol and pioglitazone markedly inhibited EMMPRIN expression during monocytes differentiation. Resveratrol significantly activated PPARgamma and GW9662 greatly decreased the effect of resveratrol on EMMPRIN and MMP-9.

CONCLUSIONEMMPRIN expression is greatly up-regulated from monocytes to macrophages, which may play a role in inducing MMPs production by monocytes/macrophages. Resveratrol can significantly inhibit EMMPRIN expression via activating PPARgamma, which may be the underlying mechanism of its inhibitory effect on MMPs production by monocytes/macrophages.

Anilides ; pharmacology ; Antineoplastic Agents, Phytogenic ; pharmacology ; Basigin ; biosynthesis ; genetics ; Blotting, Western ; Breast Neoplasms ; metabolism ; pathology ; Cell Differentiation ; drug effects ; Cell Line ; Cell Line, Tumor ; Coculture Techniques ; Dose-Response Relationship, Drug ; Female ; Humans ; Luciferases ; genetics ; metabolism ; Macrophages ; cytology ; drug effects ; metabolism ; Matrix Metalloproteinase 9 ; biosynthesis ; Monocytes ; cytology ; drug effects ; metabolism ; PPAR gamma ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; Stilbenes ; pharmacology ; Thiazolidinediones ; pharmacology ; U937 Cells

OBJECTIVETo explore the mechanism of Shenqi compound recipe (SQCR) anti-earlier diabetic artherosclerosis in GK rats.

METHODFour-month specefic pathogen free (SPF) GK rats were divided randomly according to blood glucose level into four groups: model group (5 mL x kg(-1) x d(-1) sterile water), ramipril group (positive control, 1 mg x kg(-1) x d(-1)), SQCR low dosage (0.72 g x kg(-1) x d(-1)) and SQCR high dosage group (2.88 g x kg(-1) x d(-1)) and Wistar rats as normal control group(5 mL x kg(-1) x d(-1) sterile water). GK rats took high-fat diet freely and meanwile were injected N-omega-nitro-L-arginine methyl ester (L-N-AME) intra-peritoneally with the dose of 10 mg x kg(-1) x d(-1) in order to induce earlier diabetic artherosclerosis, while normal control group took regular diet and were injected normal saline intra-peritoneally. In the experiment periods, each group was administrated correspondent substance respectively for 32 d. At the end, sampling blood by abdominal aorta and picking aorta on ice. Determined monocyte chemoattractant protein-1 (MCP-1) concentration by ELISA, messenger ribonucleic acid (mRNA) expression of MCP-1 and peroxisome proliferator-activated receptor gamma (PPARgamma) in aorta by reverse transcriptase PCR (RT-PCR).

RESULTConcentrations of MCP-1 in serum in SQCR low and high dosage groups and the mRNA expression of MCP-1 in SQCR high dosage group were all decreased significantly compared with model group (P < 0.05). The mRNA expression of PPARgamma in SQCR low and high dosage groups all increased compared with model group (P < 0.05 or P < 0.01).

CONCLUSIONInhibiting the mRNA and protein expression of MCP-1 and upregulating the mRNA expression of PPARgamma in aorta might be contribute to SQCR anti-earlier diabetic artherosclerosis in GK rats partly.

Animals ; Aorta ; metabolism ; Astragalus membranaceus ; chemistry ; Atherosclerosis ; etiology ; metabolism ; Chemokine CCL2 ; biosynthesis ; blood ; genetics ; Diabetes Mellitus, Type 2 ; complications ; metabolism ; Drug Combinations ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Male ; PPAR gamma ; biosynthesis ; genetics ; Panax ; chemistry ; Plants, Medicinal ; chemistry ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar

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 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