PPARgamma Expression Research Articles

Gestational exposure to BPA alters the expression of glucose and lipid metabolic mediators in the placenta: Role in programming offspring for obesity

Bisphenol A (BPA) exposure during pregnancy is known to predispose offspring to obesity in later life. Our previous studies demonstrated obesogenic effects in BPA-exposed offspring, including excess body fat, increased feed efficiency, adipocyte hypertrophy, and altered leptin signaling. However, the role of the placenta in mediating these effects remained unclear. This study investigates the mechanisms by which BPA exposure affects placental glucose and lipid transporters and their impact on offspring adiposity in Wistar rats. Dams were orally gavaged with BPA [0.4 (low dose-LD) and 4.0 (high dose-HD) μg/kg body weight] from gestational day (gD) 4–14. Gestational exposure to LD BPA increased the expression of 11β hydroxysteroid dehydrogenase 1 (11β HSD1) and estrogen receptor alpha (ERα) proteins (p<0.05) in the placenta compared to control and HD BPA. Similar changes were observed in the expression of mTOR signaling mediators, fatty acid transporters, and intracellular fatty acid-binding proteins. There were no changes in the dam's body weight or lipid and glucose profiles. However, there was a dose dependent increase in glucose transporter (GLUT1) expression in the placenta. While LD BPA increased hexokinase 2 expression in the placenta, HD BPA had no effect. Both doses of BPA increased IL6 expression, but only LD BPA exposure increased PPAR-gamma expression. Additionally, BPA exposure induced ADRP expression and localization, suggesting potential lipid overload in the placenta. Furthermore, BPA exposure altered the placental epigenetic profile, with increased expression of DNA methyltransferases (DNMTs). Overall, gestational BPA exposure led to dose-specific alterations in placental glucose and lipid metabolic activities, possibly playing an role in increasing the supply of these macronutrients to the fetus and predisposing the offspring to obesity.

Effects of Cryolipolysis on the Conversion of White Adipose Tissue: Pilot Study.

Cryolipolysis (CLL) is a widely employed noninvasive procedure for body fat reduction. It operates by inducing cooling, leading to the crystallization of cytoplasmic lipids, loss of cellular integrity, and apoptosis/necrosis of adipocytes, accompanied by local inflammation. Ongoing discussions revolve around CLL's potential to transform white adipocytes into brown adipocytes, potentially yielding more significant effects compared to alternative procedures. Thus, this randomized, blinded clinical study aimed to investigate the effects of CLL on adipose tissue and elucidate the mechanisms involved in its application and capacity for adipocyte conversion. Tissue samples from six patients were assessed at intervals of 45, 60, and 90 days following the application of the CLL protocol during abdominoplasty surgeries. The samples underwent immunohistochemical analyses targeting various markers, revealing higher expression of PPAR-gamma, PPAR-alpha, and UCP-1 markers in CLL-treated samples. Therefore, the present study suggests that CLL has the ability to intervene in adipocyte conversion.

NOVEL ITACONATE DERIVATIVE ATTENUATES ISOPROTERENOL INDUCED CARDIOTOXICITY IN EXPERIMENTAL ANIMALS: A MOLECULAR PATHWAY INSIGHT

Objective: 4-octyl itaconate (4-OI) is a potential drug for the treatment of myocardial infarction on account of its potent anti-inflammatory, antioxidant and anti-apoptotic properties. Thus, we hypothesise that 4-OI may attenuate isoproterenol(ISO) induced cardiotoxicity by modulating several molecular pathways in Wistar albino rats. Design and method: After getting approval from animal ethics committee(278/IAEC/2021), the experimental work was started. ISO 5mg/kg s.c., was administered daily for 15 days. Adult male rats were randomly divided into 5 groups (n=6): normal control group, ISO control group, treatment control groups. 4-OI was administered i.p. at 3 different doses (2.5,5,10 mg/kg) to rats from day 1 and continued for 15 days along with ISO. On the 16th day, surgery was performed, right carotid artery was cannulated for recording of hemodynamic parameters. Blood was drawn using cardiac puncture and rats were then sacrificed, one portion of the heart was immediately stored in 10% formalin for histopathological evaluation and second portion was kept in -80 degree C for further studies. Serum was stored for biochemical, pro-inflammatory cytokines estimation (TNF, IL-6, IL1 beta) and cardiac injury markers (CKMB, LDH). Results: 4-OI improved cardiac function and attenuated pathological changes as seen microscopically in the H&amp;E stained heart tissue sections. On ultrastructural evaluation, 4-OI treatment (5, 10mg/kg) groups presented with lesser nuclear condensation and mitochondrial swelling, as compared to the ISO control group. A significant decline in the serum and tissue levels of cardiac injury markers (CK-MB, LDH) and inflammatory markers were observed in 4-OI (5,10mg/kg) treated rats, as compared to ISO control group. Additionally, 4-OI suppressed oxidative stress and apoptosis, along with an increased PPAR-gamma expression. Molecular pathway assessment revealed that at the dose of 10mg/kg, 4-OI reduced the expression of NFkappaB, IKK-beta and enhanced the expression of Nrf-2 and HO-1. On analysis of the inflammatory MAPK pathway, expression of the pro-survival kinase ERK was also increased while JNK and p38 protein expressions were reduced. Conclusions: 4-OI at a dose of 10mg/kg mitigates myocardial toxicity in ISO treated rats by maintaining morphological structure of heart tissue with oxidative stress profile and reduced inflammation

Prmt6 represses the pro-adipogenic Ppar-gamma–C/ebp-alpha transcription factor loop

The feed-forward loop between the transcription factors Ppar-gamma and C/ebp-alpha is critical for lineage commitment during adipocytic differentiation. Ppar-gamma interacts with epigenetic cofactors to activate C/ebp-alpha and the downstream adipocytic gene expression program. Therefore, knowledge of the epigenetic cofactors associated with Ppar-gamma, is central to understanding adipocyte differentiation in normal differentiation and disease. We found that Prmt6 is present with Ppar-gamma on the Ppar-gamma and C/ebp-alpha promoter. It contributes to the repression of C/ebp-alpha expression, in part through its ability to induce H3R2me2a. During adipocyte differentiation, Prmt6 expression is reduced and the methyltransferase leaves the promoters. As a result, the expression of Ppar-gamma and C/ebp-alpha is upregulated and the adipocytic gene expression program is established. Inhibition of Prmt6 by a small molecule enhances adipogenesis, opening up the possibility of epigenetic manipulation of differentiation. Our data provide detailed information on the molecular mechanism controlling the Ppar-gamma–C/ebp-alpha feed-forward loop. Thus, they advance our understanding of adipogenesis in normal and aberrant adipogenesis.

Vitamin D supplementation alleviates insulin resistance in prediabetic rats by modifying IRS-1 and PPARγ/NF-κB expressions.

Prediabetes is a condition of intermediate hyperglycemia that may progress to type 2 diabetes. Vitamin D deficiency has been frequently linked to insulin resistance and diabetes. The study aimed to investigate the role of D supplementation and its possible mechanism of action on insulin resistance in prediabetic rats. The study was conducted on 24 male Wistar rats that were randomly divided into 6 rats as healthy controls and 18 prediabetic rats. Prediabetic rats were induced with a high-fat and high-glucose diet (HFD-G) combined with a low dose of streptozotocin. Rats with the prediabetic condition were then randomized into three groups of 12-week treatment: one group that received no treatment, one that received vitamin D3 at 100 IU/kg BW, and one group that received vitamin D3 at 1000 IU/kg BW. The high-fat and high-glucose diets were continuously given throughout the twelve weeks of treatment. At the end of the supplementation period, glucose control parameters, inflammatory markers, and the expressions of IRS1, PPARγ, NF-κB, and IRS1 were measured. Vitamin D3 dose-dependently improves glucose control parameters, as shown by the reduction of fasting blood glucose (FBG), oral glucose tolerance test (OGTT), glycated albumin, insulin levels, and markers of insulin resistance (HOMA-IR). Upon histological analysis, vitamin D supplementation resulted in a reduction of the islet of Langerhans degeneration. Vitamin D also enhanced the ratio of IL-6/IL-10, reduced IRS1 phosphorylation at Ser307, increased expression of PPAR gamma, and reduced phosphorylation of NF-KB p65 at Ser536. Vitamin D supplementation reduces insulin resistance in prediabetic rats. The reduction might be due to the effects of vitamin D on IRS, PPARγ, and NF-κB expression.

PS-B11-6: ENDOTHELIAL GHRELIN RECEPTOR INCREASE WHITE FAT WEIGHT THROUGH ACTIVATION OF MTOR-PPARGAMMA PATHWAY

Ghrelin secretion from the stomach acts on peripheral tissues to cause weight gain and fat accumulation in white adipose tissue (WAT). The role of endothelial growth hormone secretagogue-receptor (GHSR) in lipid accumulation was evaluated by restoring the expression of GHSR only in the endothelial cells of GHSR-deficient mice using the Cre-LoxP system (GHSR-EC). Radioisotope (RI) -labeled H-triolein was orally administered to evaluate lipid uptake in WAT. GHSR-deficient mice had reduced RI uptake in WAT compared to control mice, and GHSR-EC mice recovered the reduced RI uptake in GHSR-deficient mice. Furthermore, the body weight and WAT weight of GHSR-deficient mice after high-fat diet loading were significantly decreased compared with control mice, but increased in GHSR-EC mice. In vitro studies, ghrelin stimulation increased the uptake of free fatty acids by GHSR-mediated activation of the mTOR pathway and increased expression of PPARgamma. From these results, ghrelin takes up lipids via endothelial GHSR and contributes to fat accumulation in white adipose tissue.

Inhibition of Abelson Tyrosine-Protein Kinase 2 Suppresses the Development of Alcohol-Associated Liver Disease by Decreasing PPARgamma Expression

Alcohol-associated liver disease (ALD) represents a spectrum of alcohol use-related liver diseases. Outside of alcohol abstinence, there are currently no Food and Drug Administration-approved treatments for advanced ALD, necessitating a greater understanding of ALD pathogenesis and potential molecular targets for therapeutic intervention. The ABL-family proteins, including ABL1 and ABL2, are non-receptor tyrosine kinases that participate in a diverse set of cellular functions. We investigated the role of the ABL kinases in alcohol-associated liver disease. We used samples from patients with ALD compared with healthy controls to elucidate a clinical phenotype. We established strains of liver-specific Abl1 and Abl2 knockout mice and subjected them to the National Institute on Alcohol Abuse and Alcoholism acute-on-chronic alcohol feeding regimen. Murine samples were subjected to RNA sequencing, AST, Oil Red O staining, H&E staining, Western blotting, and quantitative polymerase chain reaction to assess phenotypic changes after alcohol feeding. Invitro modeling in HepG2 cells as well as primary hepatocytes from C57BL6/J mice was used to establish this mechanistic link of ALD pathogenesis. We demonstrate that the ABL kinases are highly activated in ALD patient liver samples as well as in liver tissues from mice subjected to an alcohol feeding regimen. We found that the liver-specific knockout of Abl2, but not Abl1, attenuated alcohol-induced steatosis, liver injury, and inflammation. Subsequent RNA sequencing and gene set enrichment analyses of mouse liver tissues revealed that relative to wild-type alcohol-fed mice, Abl2 knockout alcohol-fed mice exhibited numerous pathway changes, including significantly decreased peroxisome proliferator activated receptor (PPAR) signaling. Further examination revealed that PPARγ, a previously identified regulator of ALD pathogenesis, was induced upon alcohol feeding in wild-type mice, but not in Abl2 knockout mice. Invitro analyses revealed that shRNA-mediated knockdown of ABL2 abolished the alcohol-induced accumulation of PPARγ as well as subsequent lipid accumulation. Conversely, forced overexpression of ABL2 resulted in increased PPARγ protein expression. Furthermore, we demonstrated that the regulation of hypoxia inducible factor 1 subunit alpha (HIF1α) by ABL2 is required for alcohol-induced PPARγ expression. Furthermore, treatment with ABL kinase inhibitors attenuated alcohol-induced PPARγ expression, lipid droplet formation, and liver injury. On the basis of our current evidence, we propose that alcohol-induced ABL2 activation promotes ALD through increasing HIF1α and the subsequent PPARγ expression, and ABL2 inhibition may serve as a promising target forthe treatment of ALD.

The Symbiosis Between Lactobacillus acidophilus and Inulin: Metabolic Benefits in an Obese Murine Model.

Obesity is defined as having an excess of adipose tissue and is associated with the development of diabetes, hypertension, and atherosclerosis, which are the main causes of death worldwide. Research shows that probiotics and prebiotics reduce the metabolic alterations caused by high-fat diets. Therefore, this work evaluated the effect of the incorporation of Lactobacillus acidophilus (probiotic) and inulin (prebiotic) in the diet through obesity markers (biochemical, anthropometric, and molecular markers) in an obese murine model. Four treatments were administered: (1) hypocaloric diet (HD), (2) HD + L. acidophilus, (3) HD + inulin, and (4) DH supplemented with L. acidophilus + inulin for 8weeks. After treatment, glucose, triglycerides, total cholesterol, HDL-C, and LDL-C in plasma were determined. In addition, the total body weight and adipose tissue were taken to calculate the body mass index. Following RNA extraction from adipose tissue, the expression of PPAR gamma, PPAR alpha, and transforming growth factor beta 1 (TGF1β) was evaluated by semiquantitative PCR. All treatments showed an improvement in biochemical markers compared to the values of the obese model (p < 0.05). Optimal values for blood glucose (133.2 ± 14.3mg/dL), triglycerides (71 ± 4.6mg/dL), total cholesterol (48.9 ± 6mg/dL), HDL-C (40.9 ± 4.8mg/dL), and LDL-C (8.4 ± 1.7mg/dL) were obtained in the mixed treatment. Regarding fat mass index (FMI), prebiotic treatment caused the greatest reduction. On the other hand, mixed treatment increased the gene expression of PPARα and TGF1β in adipose tissue with DH with L. acidophilus and inulin treatment. This work demonstrates that the use of L. acidophilus and inulin as a complementary treatment is a viable alternative for prevention and action as a complementary treatment for obesity given the reduction in biochemical parameters and anthropometric indices; these reductions were greater than those found in the classic treatment of obesity due to the induction of the expression of genes related to lipid metabolism and anti-inflammatory cytokines, which contribute to reducing the high levels of glucose, triglycerides, and cholesterol caused by obesity.

English

Prostate cancer is the leading cause of mortality in men worldwide, and dietary fat influence its incidence. This study investigated the effect of feeding Tetracarpidium conophorum seed oil (TCSO) on 3-methylcholanthrene (MCA) induced prostate cancer in Wistar rats, the expression of cyclooxygenase-2 (COX-2) and peroxisome proliferator activated receptor gamma (PPAR-?) in the prostatic tissues. The TCSO was extracted with n-hexane in a Soxhlet apparatus and characterized by gas chromatography. Forty-eight male wistar rats (4 weeks old) were divided into three groups of 16 rats each and fed for 12 weeks. Group A and B animals were fed with diet containing TCSO extract. The animals in Groups A and C received intraperitoneally a dose of MCA (150 mg/kg) after 30 days of feeding. Groups A and B rats were fed with diet containing 10% of extracted TCSO throughout the period of the experiment. Results showed that COX-2 activity significantly decreased (p &lt; 0.05) in Group A (0.71&plusmn;0.07) and B (0.60&plusmn;0.05) when compared with Group C (1.17&plusmn;0.10) with increased COX-2 expression. PPAR-gamma activity was significantly increased (p &lt; 0.05) in Group A (1.89&plusmn;0.13) and B (2.30&plusmn;0.15) in comparison with Group C (1.16&plusmn;0.10) which has the lowest PPAR-gamma expression. TCSO extract delayed latency period in Group A where lumps were observed after 4 weeks of 3-methylcholanthrene induction in comparison with Group C where lumps were observed in less than 2 weeks of MCA induction. Gamma-linoleic acid, docosahexaenoic acid and myristoleic acid were higher in the liver cell membrane of animals in Group A compared to animals in Group C. This work therefore showed that TCSO contains bioactive components that may oppose prostate carcinogenesis induced by MCA. Key words: Cyclooxygenase-2, linoleic acid, prostate cancer, Tetracarpidium conophorum, polyunsaturated fatty acid.

Dietary supplementation with gamma-linolenic, linoleic and oleic acids decreases PPAR-gamma expression and helps the tetracycline derivative to reduce NOD2 expression in patients with acne vulgaris

Dietary supplementation with gamma-linolenic, linoleic and oleic acids decreases PPAR-gamma expression and helps the tetracycline derivative to reduce NOD2 expression in patients with acne vulgaris

Fluoxetine-induced hepatic lipid accumulation is mediated by prostaglandin endoperoxide synthase 1 and is linked to elevated 15-deoxy-Δ12,14 PGJ2.

Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14 PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14 PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment.

Effect of omega-3 fatty acid supplementation on gene expression of inflammation, oxidative stress and cardiometabolic parameters: Systematic review and meta-analysis

There is growing evidence of the beneficial health effects of omega-3 fatty acid (FAs) supplementation on gene expression of metabolic factors, but a summation of outcomes from randomized controlled trials (RCTs) is lacking. Our aim was to investigate the state of the evidence on the potential impacts of omega-3 FA oral intake on gene expression of factors related to inflammation and oxidative stress (IL-1, IL-8, Sirt-1 and TNF-α) and cardiometabolic parameters (LDLR, PPAR-gamma, adiponectin, Lp(a), and GLUT-1). Scopus, Web of Science, MEDLINE, and the Cochrane Central Register of Controlled Trials were searched from inception until December 2020. RCTs which evaluated the effect of oral intake of omega-3 FA on gene expression of cardiometabolic risk factors were included. Data were extracted using STATA software and analyzed using a random effect model. The effect size is given in a standardized mean difference (SMD) and a 95% confidence interval (95% CI). The quality of the included RCTs was assessed by Cochrane tool and almost all studies had a fair quality. Thirteen trials were included in this systematic review. Current analysis indicated that omega-3 FA intake significantly up-regulated the PPAR-gamma (SMD: 1.05; 95% CI: 0.62, 1.48; I2 = 73.9%) and down-regulation of LDLR (SMD: −0.75; 95% CI: −0.38, −0.13; I2 = 77.8%) and IL-1(SMD: −0.89; 95% CI: −1.24, −0.54; I2 = 00.0%). However, these outcomes also indicate that omega-3 FA intake has no significant effect on the gene expression of adiponectin, GLUT-1, Lp(a), IL-8, Sirt-1 and TNF-α. This analysis suggests that omega-3 FA intake may improve gene expression of PPAR-gamma, LDLR and IL-1. However, large well-designed, and long-duration RCTs are still required to clarify the effect of omega-3 FA intake on the expression of critical factors related to inflammation, oxidative stress, and cardiometabolic parameters codifying genes.

INVESTIGATION OF BIOACTIVE FLAVONOID SOURCED FROM CITRUS FRUITS ON ITS EFFECT UPON CARDIAC HYPERTROPHY: AN EXPERIMENTAL STUDY

Objective: Cardiac hypertrophy is an adaptive process of the heart. It is a leading cause for heart failure, which in turn has a high mortality rate. Hesperidin (HES) is a bioactive flavanone glycoside with agonistic activity on Peroxisome Proliferator-Activated Receptor gamma (PPAR-gamma), reported to be an inhibitor of cardiac hypertrophy signalling pathways. Therefore, we investigated the cardio-protective effect of this bioactive flavonoid in isoproterenol induced cardiac hypertrophy. Design and method: Male albino Wistar rats were divided into 6 groups (n = 6) and administered isoproterenol (3 mg/kg/day s.c.) or hesperidin (200 mg/kg/day, p.o.) and isoproterenol or enalapril (30 mg/kg/day p.o.) and isoproterenol or a combination of hesperidin and enalapril for 28 days. On the 29th day, rats were anaesthetized followed by cannulation of coronary artery to record hemodynamic parameters. Blood sample was collected and heart was excised to evaluate for parameters like biochemical, histopathological, ultrastructural and immunohistochemical studies. Results: Hesperidin significantly normalized heart weight/body weight ratio and cardiomyocyte area in the treated rats. Moreover, hesperidin improved cardiac function and attenuated pathological changes as seen in the heart tissue sections. A decline in the levels of cardiac injury markers (CK-MB, LDH) and inflammatory markers TNF-alpha, IL-6) was observed. Additionally, hesperidin suppressed oxidative stress and apoptosis along with an increased PPAR-gamma expression. Conclusions: Hesperidin has a good potential for attenuation of cardiac hypertrophy and acts by virtue of its PPAR-gamma agonistic, anti-inflammatory, anti-apoptotic and anti-oxidant properties.

SR-BI deficiency disassociates obesity from hepatic steatosis and glucose intolerance development in high fat diet-fed mice

Scavenger receptor BI (SR-BI) has been suggested to modulate adipocyte function. To uncover the potential relevance of SR-BI for the development of obesity and associated metabolic complications, we compared the metabolic phenotype of wild-type and SR-BI deficient mice fed an obesogenic diet enriched in fat. Both male and female SR-BI knockout mice gained significantly more weight as compared to their wild-type counterparts in response to 12 weeks high fat diet feeding (1.5-fold; P < .01 for genotype). Plasma free cholesterol levels were ~2-fold higher (P < .001) in SR-BI knockout mice of both genders, whilst plasma cholesteryl ester and triglyceride concentrations were only significantly elevated in males. Strikingly, the exacerbated obesity in SR-BI knockout mice was paralleled by a better glucose handling. In contrast, only SR-BI knockout mice developed atherosclerotic lesions in the aortic root, with a higher predisposition in females. Biochemical and histological studies in male mice revealed that SR-BI deficiency was associated with a reduced hepatic steatosis degree as evident from the 29% lower (P < .05) liver triglyceride levels. Relative mRNA expression levels of the glucose uptake transporter GLUT4 were increased (+47%; P < .05), whilst expression levels of the metabolic PPARgamma target genes CD36, HSL, ADIPOQ and ATGL were reduced 39%–58% (P < .01) in the context of unchanged PPARgamma expression levels in SR-BI knockout gonadal white adipose tissue. In conclusion, we have shown that SR-BI deficiency is associated with a decrease in adipocyte PPARgamma activity and a concomitant uncoupling of obesity development from hepatic steatosis and glucose intolerance development in high fat diet-fed mice.

Leonotis Leonurus improves the crosstalk between peripheral tissues both in vivo and in vitro

Ethnopharmacological relevanceUnravelling the anti-diabetic mechanism of action of L. leonurus at adipose, liver, muscle and pancreatic level. AimsTo investigate the mechanism of action of an organic extract of L. leonurus and marrubiin at the gene level in adipose, liver and muscle tissues of an obese rat model and in a co-culture model. Materials and methodsObese Wistar rats were fed a cafeteria diet for eight weeks, treated with an extract of L. Leonurus, marrubiin, sulfonylurea and aspirin for two weeks and the level of gene expression of selected markers were investigated across different tissues. The effects mediated by the different treatments were investigated in co-culture cell models involving 3T3-L1 (fat), Chang (liver), C2C12 (muscle) and INS-1 (pancreatic) cells under both normal and hyperglycemic conditions. ResultsL. leonurus extract mediated a significant increase in PPAR gamma, glucokinase, FAS and UCP2 gene expression in adipose tissue, whilst the opposite was observed in the liver. At the muscle level, a significant increase in FAS gene expression was observed relative to the obese control rats. Furthermore, the extract as well as marrubiin, modulated improvements in the adipokine profile. The co-culture models showed that the effect mediated by the extract was dependent on, the tissue type as well as the glycemic conditions. ConclusionsL. Leonurus extract as well as marrubiin exhibit anti-diabetic properties where the mechanism of action is mainly at the adipose tissue level. The increase in expression of the genes of interest mentioned above potentially play a protective role towards the liver and possibly towards the muscle tissues as well.

Meliorative effects of Pergamum harmala seed extract on obese diabetic rats

Objective: To explore the potential antidiabetic activity of methanolic extract of Harmal seeds in obese-diabetic rats. Design: Randomized controlled experimental study. Animals: Forty male Sprague Dawley rats. Procedures: The P. harmala seeds methanolic extract was prepared and orally administered at two doses of 150 and 250 mg/kg to two groups of streptozotocin-induced diabetic rats. Two additional control groups were used as healthy control and obese-diabetic control groups. Animals were euthanized after 8 weeks of experimental period, blood and tissue samples were collected. Liver tissue samples were used to determine antioxidant and oxidative stress markers; while those from adipose tissue were used for estimation of PPAR gamma expression. Results: Supplementation of P. harmala methanolic extract with both doses (150 and 250 mg/kg) to diabetic rats (G3 and G4) significantly reversed the observed alterations in the levels of blood glucose, cholesterol, triglyceride, LDL, malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) (P &lt;0.05). . In addition, the downregulation of PPAR gamma expression in diabetic rats (G2) was also restored in rats (G3 and G4) supplemented with P.harmala methanolic extract. Conclusion and clinical relevance: Our finding revealed that Harmal seed extract has a potent antidiabetic activity in streptozotocin-induced diabetic rats that can be used as a dietary supplement by diabetic patients.

Beneficial Effects of Isoflavones in the Kidney of Obese Rats Are Mediated by PPAR-Gamma Expression.

Several studies have demonstrated an important association between altered lipid metabolism and the development of kidney injury because of a high-fat diet. Fructose is also closely associated with renal injury. We opted for a combination of fructose and saturated fats in a diet (DH) that is a model known to induce renal damage in order to evaluate whether soy isoflavones could have promising use in the treatment of renal alterations. After two months of ingestion, there was an expansion of visceral fat, which was associated with long-term metabolic disorders, such as sustained hyperglycemia, insulin resistance, polyuria, dyslipidemia, and hypertension. Additionally, we found a decrease in renal blood flow and an increase in renal vascular resistance. Biochemical markers of chronic kidney disease were detected; there was an infiltration of inflammatory cells with an elevated expression of proinflammatory cytokines (tumor necrosis factor-α, interleukin (IL)-6, and IL-1β), the activation of the renin–angiotensin system, and oxidative/nitrosative stress. Notably, in rats exposed to the DH diet for 120 days, the concomitant treatment with isoflavones after 60 days was able to revert metabolic parameters, renal alterations, and oxidative/nitrosative stress. The beneficial effects of isoflavones in the kidney of the obese rats were found to be mediated by expression of peroxisome proliferator-activated receptor gamma (PPAR-γ).

Regulation of in Vitro Adipogenesis by All-trans Retinoic Acid (P21-075-19)

ObjectivesVitamin A, referred to as retinol, is an essential nutrient that affects the cell growth and differentiation including adipogenesis. Although previous studies using supraphysiological doses (over 1 mM) of all-trans retinoic acid (atRA) demonstrated anti-adipogenic activity, effects of atRA at various levels on differentiation of 3T3-L1 preadipocytes have not been extensively investigated. MethodsVarious doses of atRA were supplemented during the differentiation of 3T3-L1 preadipocytes. Lipid accumulation was assessed by Oil-Red-O staining and cellular triglyceride levels. Expression levels of adipogenic markers and cell cycle regulators were measured by quantitative real-time PCR or Western blot analyses. In addition, cell proliferation, cell cycle, and cytotoxicity were analyzed. ResultsOur study showed that the amount of cellular triglyceride and intensities of Oil-Red-O staining were decreased by supplementing atRA (1 and 10 mM) but increased by low concentrations of atRA (0.01 to 100 nM) compared with the control. Also PPARg and FABP4 were gradually over-expressed by atRA up to 1 nM but decreased at over the 1 nM concentrations. Moreover, mitotic clonal expansion (MCE) and consequential growth-arrest were analyzed as important steps in adipogenesis of 3T3-L1 cells. The 1 nM group showed more cell proliferation and thereafter a higher ratio of G0/G1 phase on day 2. Protein levels of S/G2-phase factors were dose-dependently increased by atRA up to 1 nM on day 1, but the factors were highly expressed in higher doses on day 2. G0/G1 markers were higher at the higher doses of atRA on day 1; whereas, they were highly expressed in mild or medium doses on day 2. ConclusionsOur data indicate that atRA controls adipogenesis with accompanied changes in expression of PPARgamma and FABP4, cell proliferation and follow-up growth-arrest. These results indicate that atRA can function both as a negative and positive regulator of adipogenesis depending on dosages, providing a strategy for achieving proper nutritional balance for treatment of obesity. Funding SourcesUSDA-NIFA and KRIBB Research Initiative Program.

1744-P: DBI-500 Significantly Increases Adipose Tissue Expression of PPAR-gamma and Adiponectin in DIO Mice and Significantly Decreases Markers of Fibrosis in Two Murine NASH Models

Introduction and Aims: The aims of these studies were to explore the scope of activity of oral DBI-500, an atypical glycolipid, in a murine model of prediabetic type 2 diabetes and obesity, and in two models of NASH. Methods: Part 1. Male C57BL/6 mice (14 weeks old) that received a high fat diet were divided into 3 groups (8 - 9 per group) and were either dosed with up to 144 mg/kg, 72 mg/kg or matching placebo via once daily oral gavage for 7 days. Fasting glucose, body weight and gene expression analyses were performed. Part 2. NASH was induced in male C57BL/6 mice using a standard methionine/choline deficient diet. Concomitant with initiation of diet, 4 groups of 8 mice received either placebo, 80 or 40 mg/kg DBI-500 or 40 mg/kg + metformin every other day for 4 weeks per gavage. Part 3. NASH was induced by diet in apolipoprotein-E-deficient mice using western diet (WD). Dose groups of 5 dose groups of 8 mice were dose with DBI-500 (100, 50 or 25mg/kg, or 25mg+metformin). Results: Part 1. Gene expression analysis of epidymal fat samples showed significant increases in PPAR-gamma and adiponectin expression with concomitant significant reduction in CD8+ expression. Blood glucose and body weight were reduced. Plasma levels of PAI-1 and CD40L were also significantly reduced. Part 2. MCD mice showed significant and dose dependent reduction in hepatic collagen. Part 3. In ApoE deficient mice, DBI-500 significantly reduced expression of hepatic alpha-SMA and TGF-beta1, and significantly increased PPAR-delta. BDI-500 also significantly increased HNF4-alpha. Conclusions: DBI-500 is a potential once daily novel therapy for type two diabetes and NASH that also significantly reduces markers of cardiovascular risk. DBI-500’s capacity to increase expression of HNF4-alpha strongly indicates potential as combination treatment with FXR agonists. Disclosure A. Leighton: Stock/Shareholder; Self; Dale Biotech, Inc.

Transgenic Exosomes for Thymus Regeneration.

During senescence, Wnt4 expression is down-regulated (unlike their Frizzled receptors), while PPARgamma expression increases in the thymus. Together, these changes allow for thymic degeneration to occur, observed as adipose involution. However, when restored, Wnt4 can efficiently counteract PPARgamma and prevent thymic senescence from developing. The Wnt-pathway activator miR27b has also been reported to inhibit PPARgamma. Our goal was to evaluate the Wnt4 and miR27b levels of Wnt4-transgenic thymic epithelial cell (TEC)-derived exosomes, show their regenerative potential against age-related thymic degeneration, and visualize their binding and distribution both in vitro and in vivo. First, transgenic exosomes were harvested from Wnt4 over-expressing TECs and analyzed by transmission electron microscopy. This unveiled exosomes ranging from 50 to 100 nm in size. Exosomal Wnt4 protein content was assayed by ELISA, while miR27b levels were measured by TaqMan qPCR, both showing elevated levels in transgenic exosomes relative to controls. Of note, kit-purified TEI (total exosome isolate) outperformed UC (ultracentrifugation)-purified exosomes in these parameters. In addition, a significant portion of exosomal Wnt4 proved to be displayed on exosomal surfaces. For functional studies, steroid (Dexamethasone or DX)-induced TECs were used as cellular aging models in which DX-triggered cellular aging was efficiently prevented by transgenic exosomes. Finally, DiI lipid-stained exosomes were applied on the mouse thymus sections and also iv-injected into mice, for in vitro binding and in vivo tracking, respectively. We have observed distinct staining patterns using DiI lipid-stained transgenic exosomes on sections of young and aging murine thymus samples. Moreover, in vivo injected DiI lipid-stained transgenic exosomes showed detectable homing to the thymus. Of note, Wnt4-transgenic exosome homing outperformed control (Wnt5a-transgenic) exosome homing. In summary, our findings indicate that exosomal Wnt4 and miR27b can efficiently counteract thymic adipose involution. Although extrapolation of mouse results to the human setting needs caution, our results appoint transgenic TEC exosomes as promising tools of immune rejuvenation and contribute to the characterization of the immune-modulatory effects of extracellular vesicles in the context of regenerative medicine.