PPARgamma Expression Research Articles

Barley grass juice (Hordeum vulgare L.) inhibits obesity and improves lipid profile in high fat diet-induced rat model

Ethnopharmacological relevanceHordeum vulgare (L.), commonly known as barley belonging to Poaceae family is a widely used cereal. Barley seeds are considered to possess high nutritional value and antioxidant properties. The grass of barley is also considered as a part of health drink in many parts of India. It is claimed to suppress a number of health disorders including obesity, diabetes, circulatory disorders, arthritis, anemia, excessive cholesterol levels, renal difficulties, and cancer. However, the antiobesity potential of barley grass has not been explored till now. Aim of the studyThe aim of the present study was to characterize and evaluate the anti-obesity activity of barley grass juice (Hordeum vulgare L.) in high fat diet induced model. Materials and methodsBarley grass juice was characterized by GC-MS analysis for identifying the active phytochemical constituents and was subjected to standard in vitro antioxidant studies. For in vivo studies, obesity was induced by high fat diet model in adult male Wistar rats. Atorvastatin (10 mg/kg) was used as the standard and barley grass juice was administered at two dose levels (200 and 400 mg/kg) for a period of 60 days. Anthropometric parameters, lipid profile and liver function markers were screened at regular intervals in all the treatment groups. At the end of the study, histopathological evaluations of liver and carotid artery were performed. The levels of in vivo antioxidant enzymes like SOD, catalase, reduced glutathione and lipid peroxidation in terms of malondialdehyde were also estimated in the liver homogenates. Expression levels of PPAR-gamma and caspase 3 were determined in the liver. ResultsResults indicated that barley grass juice (Hordeum vulgare L.) exhibited potent in vitro antioxidant activity. Rats administered with high fat diet for 60 days showed a significant increase in body weight, BMI, altered lipid profile, liver function markers like AST, ALT, ALP and increased expression of PPAR-gamma and caspase 3. However, administration of barley grass juice for 60 days, profoundly decreased the bodyweight, BMI, improved lipid profile and liver function markers. This was supported by the decreased expression of PPAR-gamma and caspase 3 in liver. Histopathological variations observed in liver and carotid artery of high fat diet group, when treated with BJG showed preserved hepatocytes and reduced atherosclerosis. GC-MS analysis identified the presence of 12 phytochemical constituents in barley grass juice. ConclusionOur study demonstrates the antiobesity activity of barley grass juice and it may be concluded that barley grass juice can be an effective nutraceutical in the management of obesity.

Iso-alpha acids from hops (Humulus lupulus) inhibit hepatic steatosis, inflammation, and fibrosis

Non-alcoholic fatty liver disease (NAFLD) is considered to be the hepatic manifestation of the metabolic syndrome. Iso-alpha acids (IAAs), hop-derived bitter compounds in beer, have been shown to beneficially affect different components of the metabolic syndrome such as insulin resistance and dyslipidemia. However, IAAs have not yet been studied in the context of chronic liver disease. Here we analyzed the effect of IAA on the pathogenesis of NAFLD. Once, we applied IAA to mice in combination with a NAFLD-inducing Western-type diet (WTD), and observed that IAA significantly inhibited WTD-induced body weight gain, glucose intolerance, and hepatic steatosis. Fitting to this, IAA dose-dependently inhibited cellular lipid accumulation in primary human hepatocytes (PHH) in vitro. Reduced expression of PPAR-gamma and key enzymes of lipid synthesis as well as increased expression of PPAR-alpha, indicative for increased lipid combustion, were identified as underlying mechanisms of reduced hepatocellular steatosis in vitro and in vivo. Analysis of hepatic HMOX1 expression indicated reduced oxidative stress in IAA-treated mice, which was paralleled by reduced activation of the JNK pathway and pro-inflammatory gene expression and immune cell infiltration. Furthermore, IAA reduced hepatic stellate cell (HSC) activation and pro-fibrogenic gene expression. Similarly, IAA also dose-dependently reduced oxidative stress and JNK activation in steatotic PHH, inhibited HSC activation, and reduced proliferation and pro-fibrogenic gene expression in already activated HSC in vitro. In conclusion, IAAs inhibit different pathophysiological steps of disease progression in NAFLD. Together with previous studies, which demonstrated the safety of even long-term application of IAA in humans, our data suggest IAA as promising therapeutic agent for the prevention and treatment of (non)alcoholic (fatty) liver disease.Iso-alpha-acids (IAAs) are hops-derived compounds. In this study, the authors show that IAAs inhibit development of non-alcoholic fatty liver disease. They found that IAAs reduced expression of PPAR-γ and key enzymes of lipid synthesis as well as increased expression of PPAR-α, indicative of increased lipid metabolism. IAAs also reduced oxidative stress and JNK-activation, inhibited hepatic stellate cell activation and reduced proliferation and pro-fibrogenic gene expression.

P53 mediated regulation of coactivator associated arginine methyltransferase 1 (CARM1) expression is critical for suppression of adipogenesis.

Coactivator-associated arginine methyltransferase 1 (CARM1/PRMT4) is a type I arginine methyltransferase that mediates transcriptional activation via methylation of histone H3 on R17, R26, and R42. CARM1 is also a coactivator of transcription of various transcription factors such as NF-kB, MEF2C, β-catenin, p53, PPAR-gamma etc. CARM1 has been functionally implicated in maintenance of pluripotency, cellular differentiation, and tumorigenesis; where its expression status plays an important role. Although its expression has been shown to be regulated by a few miRNAs in different contexts at post-transcriptional level, transcriptional regulation of CARM1 gene is still unexplored. In this report we demonstrate that CARM1 is a p53 responsive gene, where p53 could suppress CARM1 promoter-driven luciferase expression. CARM1 gene expression was found to be repressed by p53 in 3T3L1 preadipocytes when activated with Nutlin-3a treatment. Ectopic overexpression of CARM1 could rescue inhibitory effect of p53 on adipogenesis, suggesting a role of p53-CARM1 axis of regulation operational in the context of adipocyte differentiation. p53 and CARM1 showed antagonistic regulatory influence on PPAR-gamma expression; which suggests that p53-mediated suppression of adipogenesis could be partly via repression of CARM1 expression. Taken together these observations provide convincing mechanistic explanation for p53 function in the context of adipocyte differentiation process.

Efatutazone and T0901317 exert synergistically therapeutic effects in acquired gefitinib-resistant lung adenocarcinoma cells.

The development of acquired EGFR‐TKI therapeutic resistance is still a serious clinical problem in the management of lung adenocarcinoma. Peroxisome proliferator activated receptor gamma (PPAR γ) agonists may exhibit anti‐tumor activity by transactivating genes which are closely associated with cell proliferation, apoptosis, and differentiation. However, it remains not clear whether efatutazone has similar roles in lung adenocarcinoma cells of gefitinib resistant such as HCC827‐GR and PC9‐GR. It has been demonstrated by us that efatutazone prominently increased the mRNA and protein expression of PPAR γ, liver X receptor alpha (LXR α),as well as ATP binding cassette subfamily A member 1 (ABCA1). In the presence of GW9662 (a specific antagonist of PPAR γ) or GGPP (a specific antagonist of LXR α), efatutazone (40 μmol/L) restored the proliferation of both HCC827‐GR and PC9‐GR cells and obviously inhibited the increased protein and mRNA expression of PPAR‐gamma, LXR‐alpha, and ABCA1 induced by efatutazone. LXR α knockdown by siRNA (si‐LXR α) significantly promoted the HCC827‐GR and PC9‐GR cells proliferation, whereas incubation efatutazone with si‐LXR α restored the proliferation ability compared with the control group. In addition, combination of efatutazone and LXR α agonist T0901317 showed a synergistic therapeutic effect on lung adenocarcinoma cell proliferation and PPAR gamma, LXR A and ABCA1 protein expression. These results indicate that efatutazone could inhibit the cells proliferation of HCC827‐GR and PC9‐GR through PPAR γ/LXR α/ABCA1 pathway, and synergistic therapeutic effect is achieved when combined with T0901317.

The antihyperlipidemic and antihyperglycemic effects of ginseng flower in high fructose-fed rat via upregulation of hepatic PPAR-gamma expression

The antihyperlipidemic and antihyperglycemic effects of ginseng flower in high fructose-fed rat via upregulation of hepatic PPAR-gamma expression

Ginsenoside Rg3 ameliorated HFD-induced hepatic steatosis through downregulation of STAT5-PPARγ.

Healthy expansion of adipose tissue maintains metabolic homeostasis by storing excess chemical energy in increased fat mass. The STAT5-PPAR gamma pathway reportedly regulates adipocyte differentiation, lipid metabolism and adipogenesis. Ginsenoside Rg3 is one of the diverse groups of steroidal saponins, the major active components of ginseng, which have demonstrated pharmacological properties. In this study, we evaluated the therapeutic effects of ginsenoside Rg3 under pathological conditions in vitro and in vivo We examined the effects of ginsenoside Rg3 on glucose level, insulin sensitivity and lipogenesis in high-fat diet-fed C57BL/6 mice. Ginsenoside Rg3 was also applied to the pre-adipocyte cell line 3T3-L1 to assess the impact on lipogenesis. Ginsenoside Rg3 reduced epididymal white adipose tissue (eWAT) size and hepatic steatosis, and the amount of triglycerides (TGs) in both eWAT and liver. Similar to the murine model, Rg3-treated 3T3-L1 cells showed a reduction in lipid accumulation and amount of total TGs. Ginsenoside Rg3 regulates the expression of PPAR gamma though STAT5 in vitro and in vivo According to our results, lipid metabolism-related genes were downregulated in the high-fat mice and 3T3-L1 cell line. Rg3 shows potential for the amelioration of obesity-induced pathology, acting though STAT5-PPAR gamma to facilitate the healthy functioning of adipose tissue. This is the first report of evidence that obesity-induced insulin resistance and lipotoxicity can be treated with ginsenoside Rg3, which acts though the STAT5-PPAR gamma pathway in vivo and in vitro.

Anti-obesogenic effects of WY14643 (PPAR-alpha agonist): Hepatic mitochondrial enhancement and suppressed lipogenic pathway in diet-induced obese mice

Non-alcoholic fatty liver disease (NAFLD) presents with growing prevalence worldwide, though its pharmacological treatment remains to be established. This study aimed to evaluate the effects of a PPAR-alpha agonist on liver tissue structure, ultrastructure, and metabolism, focusing on gene and protein expression of de novo lipogenesis and gluconeogenesis pathways, in diet-induced obese mice. Male C57BL/6 mice (three months old) received a control diet (C, 10% of lipids, n = 10) or a high-fat diet (HFD, 50% of lipids, n = 10) for ten weeks. These groups were subdivided to receive the treatment (n = 5 per group): C, C-alpha (PPAR-alpha agonist, 2.5 mg/kg/day mixed in the control diet), HFD and HFD-alpha group (PPAR-alpha agonist, 2.5 mg/kg/day mixed in the HFD). The effects were compared with biometrical, biochemical, molecular biology and transmission electron microscopy (TEM) analyses. HFD showed greater body mass (BM) and insulinemia than C, both of which were tackled by the treatment in the HFD-alpha group. Increased hepatic protein expression of glucose-6-phosphatase, CHREBP and gene expression of PEPCK in HFD points to increased gluconeogenesis. Treatment rescued these parameters in the HFD-alpha group, eliciting a reduced hepatic glucose output, confirmed by the smaller GLUT2 expression in HFD-alpha than in HFD. Conversely, favored de novo lipogenesis was found in the HFD group by the increased expression of PPAR-gamma, and its target gene SREBP-1, FAS and GK when compared to C. The treatment yielded a marked reduction in the expression of all lipogenic factors. TEM analyses showed a greater numerical density of mitochondria per area of tissue in treated than in untreated groups, suggesting an increase in beta-oxidation and the consequent NAFLD control. PPAR-alpha activation reduced BM and treated insulin resistance (IR) and NAFLD by increasing the number of mitochondria and reducing hepatic gluconeogenesis and de novo lipogenesis protein and gene expressions in a murine obesity model.

Cucurbitacin E reduces obesity and related metabolic dysfunction in mice by targeting JAK-STAT5 signaling pathway.

Several members of cucurbitaceae family have been reported to regulate growth of cancer by interfering with STAT3 signaling. In the present study, we investigated the unique role and molecular mechanism of cucurbitacins (Cucs) in reducing symptoms of metabolic syndrome in mice. Cucurbitacin E (CuE) was found to reduce adipogenesis in murine adipocytes. CuE treatment diminished hypertrophy of adipocytes, visceral obesity and lipogenesis gene expression in diet induced mice model of metabolic syndrome (MetS). CuE also ameliorated adipose tissue dysfunction by reducing hyperleptinemia and TNF-alpha levels and enhancing hypoadiponectinemia. Results show that CuE mediated these effects by attenuating Jenus kinase- Signal transducer and activator of transcription 5 (JAK- STAT5) signaling in visceral fat tissue. As a result, CuE treatment also reduced PPAR gamma expression. Glucose uptake enhanced in adipocytes after stimulation with CuE and insulin resistance diminished in mice treated with CuE, as reflected by reduced glucose intolerance and glucose stimulated insulin secretion. CuE restored insulin sensitivity indirectly by inhibiting JAK phosphorylation and improving AMPK activity. Consequently, insulin signaling was up-regulated in mice muscle. As CuE positively regulated adipose tissue function and suppressed visceral obesity, dyslipedemia, hyperglycemia and insulin resistance in mice model of MetS, we suggest that CuE can be used as novel approach to treat metabolic diseases.

Regulation of Gene Expression in Downstream Signaling Molecules by Herbal Compound in Insulin Resistant Diabetic Rats

Background: In previous studies, Sharma et al. has already isolated an anti-hyperglycemic compound from the fruit pulp of Eugenia jambolana using HPLC and other chromatographic techniques. However, the effect of antihyperglycemic compound (FIIc) on the expression of PPAR gamma, IRS-1 and IRS-2 in high sucrose diet induced type 2 diabetic rats has not been studied so far. Methods: There were exactly 24 Male Wistar rats were taken and fed on High Sucrose Diet (HSD) for the development of type 2 diabetic animal for 30 weeks. Active compound FIIc was given to group C and Pioglitazone to group D at dose of 20 mg/kg of b.w. orally for 30 weeks respectively. Blood was drawn for the estimation of plasma glucose and serum insulin at week o and at week 30 from retro orbital plexus. At the end of the study animal were sacrificed and organs including pancreas and skeletal muscles were isolated and stored at -80°C. Total RNA was isolated by using Trizol method and expression of PPAR gamma, IRS-1 and IRS-2 was quantified and compared among the study groups by Real Time PCR. Results: After treatment with FIIc for 30 weeks we found a significant reduction in post prandial blood glucose levels in group C rats compared to group B. Serum insulin was also reduced in group C rats compared to group B. In skeletal muscles the mRNA expression of PPAR γ and IRS-1 was found to be 2.48 fold and 2.56 fold increased respectively as compared to group B. Similarly the mRNA expression of IRS-2 in pancreas was found to be 2.69 folds increased as compared to group B. Conclusion: FIIc treatment for 30 weeks improves glycemic control and insulin sensitivity by increasing the mRNA expression of PPAR γ, IRS-1 and IRS-2.

Deletion of angiotensin II type 2 receptor accelerates adipogenesis in murine mesenchymal stem cells via Wnt10b/beta-catenin signaling

Recent evidence suggests that the renin-angiotensin system (RAS) has a vital role in adipocyte biology and the pathophysiology of metabolic syndrome. Obesity is the main culprit of metabolic syndrome; and mesenchymal stem cells (MSCs) have been forwarded as a major source of adipocyte generation. Previously, we reported that MSCs have a local RAS and that pharmacological blockade of angiotensin II type 2 receptor (AT2R) promotes adipogenesis in human MSCs. However, the definitive roles of AT2R and how AT2R functions in adipogenesis remains unknown. To this end, we employed AT2R-null murine MSCs to characterize how AT2R affects the differentiation of MSCs into adipocytes. Murine MSCs were isolated from AT2R-null mice and wild-type littermates, grown to confluency, and then differentiated into adipocytes. Adipogenesis was quantitated by assessing the lipid droplet accumulation. Using the lipophilic fluorescent dye, the AT2R-null cells showed significantly increased total fluorescence (261.6±49.6% vs littermate) on day 7. Oil red O staining followed by extraction of the absorbed dye and measurement of the absorbance on day 14 also exhibited significantly increased lipid droplet accumulation in the AT2R-null cells (202.7±14.1% vs littermate). We also examined the expression of adipogenic marker genes by quantitative RT-PCR. The AT2R-null group exhibited significantly increased expression of PPAR-gamma, fatty acid synthase, and adiponectin (vs littermate). We further examined the role of Wnt10b/beta-catenin signaling, which reportedly has an important inhibitory role in adipogenesis. The AT2R-null group exhibited significantly decreased Wnt10b expression accompanied by decreased beta-catenin (vs littermate). Our results thus revealed that the AT2R inhibits adipogenic differentiation in murine MSCs. Moreover, this inhibitory effect is associated with Wnt10b/beta-catenin signaling. These results provide important insights into the pathophysiology of obesity and obesity-related consequences such as metabolic syndrome, hinting at possible future therapies.

Effect of High Glucose Concentration on Human Preadipocytes and Their Response to Macrophage-Conditioned Medium.

Adipose tissue expands via differentiation of preadipocytes into adipocytes (adipogenesis) and/or hypertrophy of existing adipocytes. A low adipogenic capacity promotes adipocyte hypertrophy, causing inflammatory macrophage accumulation and insulin resistance. Macrophage-conditioned medium (MacCM) inhibits adipogenesis and promotes adipocyte inflammation, but it is unknown whether these effects are altered by high glucose (HG) versus normal glucose (NG) concentrations. Our aim was to compare the effect of HG-MacCM versus NG-MacCM on human adipogenesis and adipocyte inflammation. Human monocyte-derived macrophages (MDMs) were placed in 5 mmol/L (NG) or 25 mmol/L (HG) glucose for 24 hours. MacCM was collected and its effect on differentiation of human subcutaneous abdominal preadipocytes and adipocyte inflammation was evaluated. HG-MacCM, but not NG-MacCM, inhibited triacylglycerol (TG) accumulation and protein expression of peroxisome proliferator-activated receptor γ (PPARgamma) during human adipogenesis. Preadipocytes differentiated in HG-MacCM displayed a more pro-inflammatory phenotype, as assessed by increased interleukin-6 and monocyte chemotactic protein-1 (MCP-1), as well as reduced adiponectin mRNA expression. In MDMs, HG increased phosphorylation of inhibitor of kappaB kinase (IKK)-beta and decreased protein expression of inhibitor of kappaB alpha. HG also reduced protein expression of PPARgamma in MDMs. However, no MDM changes in mRNA expression of MCP-1, interleukin-1beta or tumor necrosis factor-alpha were detected. The stimulatory effect of HG-MacCM on MCP-1 expression in adipocytes was partially inhibited when MDMs were treated with sc-514 (IKKbeta inhibitor). High glucose concentration accentuates the anti-adipogenic and pro-inflammatory effects of MacCM on human preadipocytes.

S&T-31 TRANSCRIPTIONAL REGULATION OF CORTICOTROPIN RELEASING FACTOR

You have accessJournal of UrologyScience & Technology Posters1 Apr 2016S&T-31 TRANSCRIPTIONAL REGULATION OF CORTICOTROPIN RELEASING FACTOR Lizath Aguiniga, Anthony Schaeffer, and David Klumpp Lizath AguinigaLizath Aguiniga More articles by this author , Anthony SchaefferAnthony Schaeffer More articles by this author , and David KlumppDavid Klumpp More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.2860AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Interstitial cystitis (IC) patients suffer from chronic pelvic pain and bladder dysfunction. IC patients have altered cortisol levels suggesting dysregulation of the hypothalamic-pituitary adrenal (HPA) axis and suffer from exacerbated symptoms in response to high stress. Corticotropin-releasing factor (CRF) is the initiator of the HPA axis and mediates stress responses and voiding control, where increased CRF levels in Barrington′s nucleus induce bladder dysfunction. Arachidonic acid (AA) metabolites have been shown to induce CRF expression, however the transcriptional mediators of this modulation are unknown. We are investigating which transcription factors mediate AA-induced CRF gene expression. METHODS We used MIRAGE software to identify candidate transcription factor binding sites in a 1kb region of the human CRF gene promoter. We identified a peroxisome proliferator activated hormone response element (PPRE) and two Xenobiotic Responsive Element (XRE) sites as candidate mediators of AA-dependent CRF induction. Site directed mutations of the PPRE and XRE sites were generated in a CRF luciferase reporter plasmid. We evaluated the WT CRF promoter and the mutants for their responses to AA. We also over-expressed transcription factors AhR and PPAR gamma and evaluated AA-induced CRF expression in HEK 293T cells. We used the hypothalamic cell line N42, which has functional CRF expression to assess the role of AhR. We over-expressed AhR, induced with AA and used RT PCR to quantify CRF expression. RESULTS AA induction in the PPRE mutant resulted in increased CRF promoter activity compared to WT, whereas XRE1 had decreased activity. The mutation of both XRE1 and XRE2 resulted in decreased responsiveness to AA. Over expression of PPAR gamma alone showed no change, while over expression of AhR alone showed a significant increase in AA-induced CRF expression; this was inhibited by over-expression of both AhR and PPAR gamma in HEK 293T cells. Over expression of AhR in N42 cells resulted in increased CRF mRNA in response to AA induction. CONCLUSIONS These results suggest AhR binding to the XRE sites modulates AA-dependent CRF gene expression. PPAR gamma inhibits AA-dependent CRF gene expression. Continued studies will use mouse models to examine the in vivo role of AhR and PPAR gamma in modulating voiding in response to stress. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e321 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Lizath Aguiniga More articles by this author Anthony Schaeffer More articles by this author David Klumpp More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Effect of Intestinal Permeability and Gastrointestinal Segmental Transit Time Determined by Wireless Motility Capsule (SmartPill®)

Peroxisome proliferator-activated receptor gamma (PPAR gamma), a nuclear transcription factor, plays a critical role in the regulation of gene expression associated with inflammation and cancer. PPAR gamma is expressed in human gastric cancer as well as in colon cancer. Activation of PPAR gamma by ligand produces pro-apoptotic effect and ameliorate growing of cancer cells. Helicobacter pylori (H. pylori) is a main etiologic agent for gastric inflammation, and raises cell turnover in gastric epithelium. Longstanding infection with this organism is related with the development of non-cardiac gastric cancer. The aim of this study was to investigate the effect of H. pylori on the expression of PPAR gamma protein and mRNA in chronic gastritis.Gastric biopsy samples were taken from H. pylori infected (n=18) and non-infected (n=21) patients during endoscopic examination. PPAR gamma expressions were assessed by real time polymerase chain reaction and immunohistochemistry.PPAR gamma was localized to the nuclei of the foveolar epithelial cells in both infected and non-infected mucosa. PPAR gamma protein expression was higher in H. pylori infected patients than in non-infected patients (3.8+/-0.4 vs. 2.6+/-1.0, H. pylori infected and non-infected, respectively; p<0.05). However, PPAR gamma mRNA levels were not significantly different between the two groups (24+/-18 vs. 29+/-25, H. pylori infected and noninfected, respectively).PPAR gamma expression is increased in the gastric mucosa of H. pylori infected chronic gastritis, which suggests a certain role of PPAR gamma in the mucosal inflammatory reaction to H. pylori infection.

Abstract 1848: PPARγ function is attenuated by full length androgen receptor and the AR-V7 variant in human prostate cancer cells

Abstract The peroxisome proliferator activated receptor gamma (PPARγ) is a ligand-activated transcription factor that regulates in vitro and in vivo growth of castration-resistant human prostate cancer (PCa) cells. However, the factors that control expression of PPARγ within human PCa have not been characterized. We have previously shown that the androgen dihydrotestosterone decreases PPARγ levels and transcriptional activity in human PCa cells. Dihydrotestosterone serves as a high affinity ligand for the 110 kD form of the androgen receptor (AR-FL). Recent studies have shown the development of castration-resistant forms of prostate cancer is not only due to reactivation of AR-FL but also results from the expression of androgen receptor splice variants (ARVs) that lack the ligand-binding domain of the receptor. The goal of this study is to define the extent to which AR-FL and an ARV found in castration-resistant prostate cancer, AR-V7, regulate PPARγ expression and function. We first examined the role of AR-FL in the AR-positive C4-2 cell line. siRNA-mediated knockdown of endogenous AR-FL within C4-2 cells increased PPARγ protein and transcriptional activity. We next used reporter assays to further define the role of AR-FL and AR-V7 in PPARγ function. In these experiments, we first transfected plasmid vectors that express the AR-V7 or AR-FL into the AR null PC-3 prostate cancer cell line. A luciferase-based reporter assay was then used to measure alterations in PPARγ transcriptional activity within transfected cells. The addition of AR-FL to PC-3 cells resulted in reduced basal PPARγ luciferase activity. The ability of the ligand rosiglitazone to increase PPARγ activation was also suppressed in AR-FL positive PC-3 cells. A comparable decrease in ligand-induced PPARγ activation was detected in PC-3 cells that expressed AR-V7. The reduction in PPARγ activity produced by AR-FL and AR-V7 was likely not due to alterations in PPAR gamma expression, for we did not detect a consistent reduction in PPARγ mRNA and protein in transfected cells. Overall these data suggest that both AR-FL and AR-V7 are negative regulators of PPARγ function. Moreover, the AR-V7 stimulated reduction in PPARγ activity does not require the presence of AR-FL. Studies currently are underway to define the effect of endogenous AR-V7 on PPARγ expression and activity. This project was supported by NIGMS RISE grant (2R25GM059994-13), a NCI Mentored Career Development Award (K01CA114253), and the Vanderbilt CTSA grant UL1 RR024975-01 from NCRR/NIH. Citation Format: Emuejevoke Olokpa, Lamonica V. Stewart. PPARγ function is attenuated by full length androgen receptor and the AR-V7 variant in human prostate cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1848. doi:10.1158/1538-7445.AM2015-1848

Iodine Affects Differentiation and Migration Process in Trophoblastic Cells.

Iodine deficiency is associated with oxidative stress increase and preeclampsia during gestation, suggesting that iodine concentration plays an important role in the normal placenta physiology. The question raised is to analyze the effect of iodine deficiency on oxidative stress, viability, differentiation, and migration process and changes in the expression of differentiation and migration markers. Iodine deprivation was done using potassium perchlorate (KCLO4) to block sodium iodide symporter (NIS) transporter and 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid DIDS to inhibit pendrine (PEN) transport for 3-48 h. Then trophoblast cells were treated with low iodine doses of 5-500 μM and high iodine doses of 100-5000 μM. Oxidative stress, viability, and human chorionic gonadotropin (hGC) were measured by colorimetric methods. Migration throphoblast cells were evaluated by both wound healing and Boyden chamber assays. Changes in mRNA expression were analyzed by real-time RT-PCR. Iodine deprivation induces a significant increase of reactive oxygen species (ROS), viability, and migration process vs control cells. We found a significant overregulation in the mRNA's peroxisome proliferator-activated receptor (PPAR-gamma), Snail, and matrix metalloproteinase-9 (MMP-9) mRNA's in cells deprived of iodine, as well as a down glial cell missing-1 (GCM-1) regulation, hGC, pregnancy-associated plasma protein-A (PAPP-A), and E-cadherin mRNA expression. The expression of hypoxic induction factor alpha (HIFα) mRNA does not change with iodine deprivation. In cells deprived of iodine, supplementing low iodine doses (5-500 μM) does not induce any significant changes in viability. However, ROS and migration process were decreased, although we found an increased human chorionic gonadotropin (hCG) secretion as a differentiation marker. In addition, we found that PPAR-gamma, Snail, and MPP-9 mRNAs expression are downregulated with low iodine doses, in contrast with GCM-1, PAPP-A, hGC, and E-cadherin that increase their expression vs cells deprived of iodine. High iodine doses (1000-5000 μM) have shown cytotoxic effects. Based on our results, iodine is important for keeping the proliferation/differentiation balance in the placenta.

Molecular Mechanism on Inhibition of MB Angiogenesis by Curcumin Blocking the Wnt/β-Catenin and NF-κB Signaling Pathway and Inhibiting the Expression of VEGFs/VEGFRs

Medulloblastoma (MB) is one of the most common malignant tumors in pediatric brain. The genesis and development of MB are related to abnormal and persistent activation of the Wnt/β-catenin abnormal and NF-κB signaling pathway. The VEGF, as the main target gene regulated by the crosstalk between the two signaling pathways, is closely related to MB. In previous studies, We found that the genesis of MB is associated with the abnormal expression of key molecular GSK-3β,β-catenin and downstream target gene PPAR-gamma in Wnt /β-catenin signaling pathway.It also found that, there have abnormal expression of VEGF-A, C and its receptor VEGFR-2 in MB, and positively correlate with β-catenin. curcumin has anti-angiogenic function, but the exact mechanism is unclear. Combining with the early research findings and the latest literatures, we hypothesized that curcumin can inhibit the expression of VEGFs/VEGFRs by blocking the Wnt/β-catenin and NF-κB signaling pathway.

An experimental study of muscular injury repair in a mouse model of notexin-induced lesion with EPI® technique.

BackgroundThe mechanisms of muscle injury repair after EPI® technique, a treatment based on electrical stimulation, have not been described. This study determines whether EPI® therapy could improve muscle damage.MethodsTwenty-four rats were divided into a control group, Notexin group (7 and 14 days) and a Notexin + EPI group. To induce muscle injury, Notexin was injected in the quadriceps of the left extremity of rats. Pro-inflammatory interleukin 1-beta (IL-1beta) and tumoral necrosis factor-alpha (TNF-alpha) were determined by ELISA. The expression of receptor peroxisome gamma proliferator activator (PPAR-gamma), vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-1 (VEGF-R1) were determined by western-blot.ResultsThe plasma levels of TNF-alpha and IL-1beta in Notexin-injured rats showed a significant increase compared with the control group. EPI® produced a return of TNF-alpha and IL-1beta values to control levels. PPAR-gamma expression diminished injured quadriceps muscle in rats. EPI® increased PPAR-gamma, VEGF and VEGF-R1 expressions. EPI® decreased plasma levels of pro-inflammatory TNF-alpha and IL-1beta and increased anti-inflammatory PPAR-gamma and proangiogenic factors as well as VEGF and VEGF-R1 expressions.ConclusionThe EPI® technique may affect inflammatory mediators in damaged muscle tissue and influences the new vascularization of the injured area. These results suggest that EPI® might represent a useful new therapy for the treatment of muscle injuries. Although our study in rats may represent a valid approach to evaluate EPI® treatment, studies designed to determine how the EPI® treatment may affect recovery of injury in humans are needed.

Placental fibroblast growth factor 21 is not altered in late-onset preeclampsia.

BackgroundPreeclampsia (PE) is associated with alterations of placental function. The incidence of PE is higher in insulin resistant states. Women with PE have high circulating levels of the metabolic regulator fibroblast growth factor 21 (FGF21). FGF21 is synthesized in the placenta. The aim of this study was to compare the expression of FGF21, its receptors, downstream targets and transcriptional regulators in placental tissue from pregnancies with and without late-onset PE. Circulating FGF21 in maternal and cord blood was also studied.MethodsmRNA expression was determined by semi-quantitative real-time PCR and normalized for cellular composition in 17 women with and 20 without PE. Protein expression was quantified by Western Blot. FGF21 levels were measured by ELISA in maternal and cord serum of ten mother-baby dyads per condition.ResultsPlacental FGF21 mRNA and protein expression were similar in PE compared with control. Placental mRNA expression of the FGF receptors (1–4) and the co-receptor beta-Klotho was not different between the groups. There was no difference in the expression of the glucose transporters GLUT1, 3 or 4. PPAR-alpha but not PPAR-gamma expression was decreased in PE. Maternal FGF21 serum levels were not significantly different in PE. FGF21 was detected in cord blood of 6 infants (4 PE, 2 controls) but was undetectable in 14 infants.ConclusionsLate-onset PE is not associated with major changes to the expression of FGF21, its receptors or metabolic targets.Electronic supplementary materialThe online version of this article (doi:10.1186/s12958-015-0006-3) contains supplementary material, which is available to authorized users.

Effect of apigenin on protein expressions of PPARs in liver tissues of rats with nonalcoholic steatohepatitis

To 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). The 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 PPARα and PPARgamma in liver tissue were assessed by immunohistochemistry and RT-PCR.Statistical analysis was performed by the LSD test and Games-Howell test. The 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 PPARα (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). Apigenin 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.

Calreticulin inhibits commitment to adipocyte differentiation.

Calreticulin, an endoplasmic reticulum (ER) resident protein, affects many critical cellular functions, including protein folding and calcium homeostasis. Using embryonic stem cells and 3T3-L1 preadipocytes, we show that calreticulin modulates adipogenesis. We find that calreticulin-deficient cells show increased potency for adipogenesis when compared with wild-type or calreticulin-overexpressing cells. In the highly adipogenic crt(-/-) cells, the ER lumenal calcium concentration was reduced. Increasing the ER lumenal calcium concentration led to a decrease in adipogenesis. In calreticulin-deficient cells, the calmodulin-Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) pathway was up-regulated, and inhibition of CaMKII reduced adipogenesis. Calreticulin inhibits adipogenesis via a negative feedback mechanism whereby the expression of calreticulin is initially up-regulated by peroxisome proliferator-activated receptor gamma (PPAR gamma). This abundance of calreticulin subsequently negatively regulates the expression of PPAR gamma, lipoprotein lipase, CCAAT enhancer-binding protein alpha, and aP2. Thus, calreticulin appears to function as a Ca(2+)-dependent molecular switch that regulates commitment to adipocyte differentiation by preventing the expression and transcriptional activation of critical proadipogenic transcription factors.