Serum adiponectin and peroxisome proliferator-activated receptors-γ levels in obese patients with and without prediabetes.

OBJECTIVE: Obesity is an increasingly prevalent global health problem, which is generally caused by the increase in body fat mass above normal and observed in all societies. If the blood glucose level is higher than normal but not high enough to diagnose diabetes, this condition is defined as prediabetes. Adiponectin increases fatty acid oxidation and insulin sensitivity and is closely associated with obesity. One of the nuclear receptor superfamily member peroxisome proliferator-activated receptors is shown to have an important role in various metabolic reactions. This study aimed to investigate the serum levels of adiponectin and peroxisome proliferator-activated receptors-gamma parameters, which are closely related to adipose tissue, energy metabolism, and insulin sensitivity, in obese patients with and without prediabetes. METHODS: For this purpose, 52 obese patients with prediabetes, 48 obese patients with non-prediabetes, and 76 healthy individuals were included in this study. Serum adiponectin and peroxisome proliferator-activated receptors-γ levels were analyzed by ELISA. RESULTS: Serum adiponectin levels were significantly higher in obese patients with prediabetes (18.15±15.99) compared with the control group (15.17±15.67; p=0.42). No significant difference was observed in both adiponectin and peroxisome proliferator-activated receptors-γ levels in the obese patients with the non-prediabetes group compared with the control group. However, no significant difference was observed in the obese patients with prediabetes group and obese patients with non-prediabetes group. CONCLUSION: Our results suggest that adiponectin may serve as an indicator of prediabetes. This implies that examining adiponectin levels in individuals diagnosed with prediabetes may enhance our understanding of the metabolic processes closely linked to prediabetes and related conditions.

Peroxisome Proliferator-Activated Receptor Gamma (PPARγ) Levels in Adolescent with Bipolar Disorder and Their Relationship with Metabolic Parameters.

Peroxisome proliferator-activated receptor gamma (PPARγ) is one of the immune and metabolic regulatory agents. This study examined the serum PPARγ levels and metabolic syndrome (MetS) parameters in pediatric bipolar disorder (PBD) adolescents and compared them with healthy subjects. Serum PPARγ levels, fasting blood glucose (FBG), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and fasting insulin levels of 39 PBD-type I (age range: 14-18) and 36 age- and sex-matched healthy control subjects were compared. The anthropometric measurements were also analyzed, including body weight, height, body mass index (BMI), waist circumference (WC), and blood pressure measurements. The PPARγ levels were significantly lower, and the MetS prevalence was significantly higher in the PBD group than in the control group. The mean BMI, WC, serum TG, and FBG values of the PBD group were statistically higher than the healthy control group. There was no significant relationship between the PPARγ levels and metabolic parameters except fasting glucose. Lower PPARγ activity and higher MetS prevalence in PBD indicate dysregulation of immune and metabolic regulatory parameters. These results may shed light on developing new PBD medications.

Euphausia pacifica (North Pacific Krill): Review of Chemical Features and Potential Benefits of 8-HEPE against Metabolic Syndrome, Dyslipidemia, NAFLD, and Atherosclerosis.

Marine n-3 fatty acids are well known to have health benefits. Recently, krill oil, which contains phospholipids, has been in the spotlight as an n-3 PUFA-containing oil. Euphausia pacifica (E. pacifica), also called North Pacific krill, is a small, red crustacean similar to shrimp that flourishes in the North Pacific Ocean. E. pacifica oil contains 8-hydroxyeicosapentaenoic acid (8-HEPE) at a level more than 10 times higher than Euphausia superba oil. 8-HEPE can activate the transcription of peroxisome proliferator-activated receptor alpha (PPARα), PPARγ, and PPARδ to levels 10, 5, and 3 times greater than eicosapentaenoic acid, respectively. 8-HEPE has beneficial effects against metabolic syndrome (reduction in body weight gain, visceral fat area, amount of gonadal white adipose tissue, and gonadal adipocyte cell size), dyslipidemia (reduction in serum triacylglycerol and low-density lipoprotein cholesterol and induction of serum high-density lipoprotein cholesterol), atherosclerosis, and nonalcoholic fatty liver disease (reduction in triglyceride accumulation and hepatic steatosis in the liver) in mice. Further studies should focus on the beneficial effects of North Pacific krill oil products and 8-HEPE on human health.

TWIST2 and the PPAR signaling pathway are important in the progression of nonalcoholic steatohepatitis.

BACKGROUND: To investigate the roles of the transcription factors twist family bHLH transcription factor 1 (TWIST1), twist family bHLH transcription factor 2 (TWIST2), and peroxisome proliferator activated receptor gamma (PPARγ) in the progression of nonalcoholic steatohepatitis. METHODS: The protein levels of TWIST1, TWIST2 and PPARγ were determined in the serum of nonalcoholic fatty liver disease (NAFLD) patients and healthy controls by enzyme-linked immunosorbent assay (ELISA). An in vivo model for fatty liver was established by feeding C57BL/6 J mice a high-fat diet (HFD). An in vitro model of steatosis was established by treating LO-2 cells with oleic acid (OA). RNA sequencing was performed on untreated and OA-treated LO-2 cells followed by TWIST1, TWIST2 and PPARγ gene mRNA levels analysis, Gene Ontology (GO) enrichment and pathway analysis. RESULTS: The TWIST2 serum protein levels decreased significantly in all fatty liver groups (P < 0.05), while TWIST1 varied. TWIST2 tended to be lower in mice fed an HFD and was significantly lower at 3 months. Similarly, in the in vitro model, the TWIST2 protein level was downregulated significantly at 48 and 72 h after OA treatment. RNA sequencing of LO-2 cells showed an approximately 2.3-fold decrease in TWIST2, with no obvious change in TWIST1 and PPARγ. The PPAR signaling pathway was enriched, with 4 genes upregulated in OA-treated cells (P = 0.0018). The interleukin (IL)-17 and tumor necrosis factor (TNF) signaling pathways were enriched in OA-treated cells. CONCLUSIONS: The results provide evidence that the TWIST2 and PPAR signaling pathways are important in NAFLD and shed light on a potential mechanism of steatosis.

Fortifying Butterfat with Soybean Oil Attenuates the Onset of Diet-Induced Non-Alcoholic Steatohepatitis and Glucose Intolerance.

The addition of plant oils such as soybean oil (S) to a diet rich in saturated fatty acids is discussed as a possible route to prevent or diminish the development of metabolic disease. Here, we assessed whether a butterfat-rich diet fortified with S affects the development of early non-alcoholic steatohepatitis (NASH) and glucose intolerance. Female C57BL/6J mice were fed a standard-control diet (C); a fat-, fructose-, and cholesterol-rich diet (FFC, 25E% butterfat, 50% (wt./wt.) fructose, 0.16% (wt./wt.) cholesterol); or FFC supplemented with S (FFC + S, 21E% butterfat + 4E% S) for 13 weeks. Indicators of liver damage, inflammation, intestinal barrier function, and glucose metabolism were measured. Lipopolysaccharide (LPS)-challenged J774A.1 cells were incubated with linolenic and linoleic acids (ratio 1:7.1, equivalent to S). The development of early NASH and glucose intolerance was significantly attenuated in FFC + S-fed mice compared to FFC-fed mice associated with lower hepatic toll-like receptor-4 mRNA expression, while markers of intestinal barrier function were significantly higher than in C-fed mice. Linolenic and linoleic acid significantly attenuated LPS-induced formation of reactive nitrogen species and interleukin-1 beta mRNA expression in J774A.1 cells. Our results indicate that fortifying butterfat with S may attenuate the development of NASH and glucose intolerance in mice.

Adipokines and Metabolic Regulators in Human and Experimental Pulmonary Arterial Hypertension.

Pulmonary hypertension (PH) is associated with meta-inflammation related to obesity but the role of adipose tissue in PH pathogenesis is unknown. We hypothesized that adipose tissue-derived metabolic regulators are altered in human and experimental PH. We measured circulating levels of fatty acid binding protein 4 (FABP-4), fibroblast growth factor -21 (FGF-21), adiponectin, and the mRNA levels of FABP-4, FGF-21, and peroxisome proliferator-activated receptor γ (PPARγ) in lung tissue of patients with idiopathic PH and healthy controls. We also evaluated lung and adipose tissue expression of these mediators in the three most commonly used experimental rodent models of pulmonary hypertension. Circulating levels of FABP-4, FGF-21, and adiponectin were significantly elevated in PH patients compared to controls and the mRNA levels of these regulators and PPARγ were also significantly increased in human PH lungs and in the lungs of rats with experimental PH compared to controls. These findings were coupled with increased levels of adipose tissue mRNA of genes related to glucose uptake, glycolysis, tricarboxylic acid cycle, and fatty acid oxidation in experimental PH. Our results support that metabolic alterations in human PH are recapitulated in rodent models of the disease and suggest that adipose tissue may contribute to PH pathogenesis.

Imbalanced serum levels of resolvin E1 (RvE1) and leukotriene B4 (LTB4) in patients with allergic rhinitis.

Timely and successful resolution of acute inflammation plays a crucial role in preventing the development of chronic airway inflammation in allergic rhinitis (AR). This study intends to assess the serum levels of pro-inflammatory leukotriene B4 (LTB4), anti-inflammatory mediators, including resolvin E1 (RvE1), RvD1, IL-10, and TGF-ß, besides mRNA expression level of G-protein coupled receptor 120 (GPR120) and peroxisome proliferator-activated receptor-γ (PPAR-γ) receptors in peripheral blood leukocytes of AR patients. Thirty-seven AR patients and thirty age- and gender-matched healthy subjects were enrolled in this study. The serum levels of LTB4, RvE1, RvD1, IL-10, and TGF-ß were measured using enzyme-linked immunosorbent assay (ELISA) technique, and the mRNA expression level of GPR120 and PPAR-γ was assessed by the real-time PCR method. The serum levels of RvE1 and LTB4 were significantly higher in patients with AR than in healthy subjects (P < 0.01 and P < 0.0001, respectively). However, a significantly lower ratio of RvE1 and RvD1 to LTB4 was found in patients with AR relative to healthy subjects (P < 0.05 and P < 0.0001, respectively). Likewise, the serum levels of both IL-10 and TGF-ß cytokines were significantly reduced in patients with AR compared to healthy subjects (P < 0.01 and P < 0.0001, respectively). Furthermore, the mRNA expression of PPAR-γ was significantly lower in patients with AR than in healthy subjects (P < 0.05). Our findings indicate that imbalanced pro-resolving lipid mediator RvE1 and pro-inflammatory LTB4 might contribute to the defective airway inflammation-resolution and subsequent progression toward chronic inflammation in AR patients.

Physical fitness status modulates the inflammatory proteins in peripheral blood and circulating monocytes: role of PPAR-gamma.

The aim of this study was to analyze the metabolic and molecular profile according to physical fitness status (Low or High VO2max) and its impacts on peripheral and cellular inflammatory responses in healthy men. First (Phase I), inflammatory profile (TNF-α, IL-6, IL-10) was analyzed at baseline and post-acute exercise sessions performed at low (< 60% VO2max) and high (> 90% VO2max) intensities considering the individual endotoxin concentrations. Next (Phase II), monocyte cell cultures were treated with LPS alone or associated with Rosiglitazone (PPAR-γ agonist drug) to analyze cytokine production and gene expression. Monocyte subsets were also evaluated by flow cytometry. A positive relationship was observed between LPS concentrations and oxygen uptake (VO2max) (r = 0.368; p = 0.007); however, in the post-exercise an inverse correlation was found between LPS variation (Δ%) and VO2max (r = -0.385; p = 0.004). With the low-intensity exercise session, there was inverse correlation between LPS and IL-6 concentrations post-exercise (r = -0.505; p = 0.046) and a positive correlation with IL-10 in the recovery (1 h post) (r = 0.567; p = 0.011), whereas with the high-intensity exercise an inverse correlation was observed with IL-6 at pre-exercise (r = -0.621; p = 0.013) and recovery (r = -0.574; p = 0.016). When monocyte cells were treated with LPS, High VO2max individuals showed higher PPAR-γ gene expression whereas Low VO2max individuals displayed higher IL-10 production. Additionally, higher TLR-4, IKK1, and PGC-1α gene expression were observed in the High VO2max group than Low VO2max individuals. In conclusion, even with elevated endotoxemia, individuals with High VO2max exhibited higher IL-6 concentration in peripheral blood post-acute aerobic exercise and lower IL-10 concentration during recovery (1 h post-exercise). The anti-inflammatory effects linked with exercise training and physical fitness status may be explained by a greater gene expression of IKK1, TLR-4, and PGC-1α, displaying an extremely efficient cellular framework for the PPAR-γ responses.

ACSL1 affects Triglyceride Levels through the PPARγ Pathway.

In clinical cohort studies, high expression of long-chain acyl-coenzyme A synthetases 1 (ACSL1 gene) in peripheral white blood cells of patients with acute myocardial infarction (AMI) has been utilized as molecular markers of myocardial infarction diagnosis. The plasma triglyceride level of AMI patients is significantly higher than that of healthy individuals. We hypothesized that the high expression of ACSL1 increases the level of triglyceride, which is one of the pathogenesis of AMI promoted by ACSL1. In this report, cell culture based methods were adopted to test the hypothesis and further investigate the effect and mechanism of ACSL1 on lipid metabolism. In this study, liver cells of healthy individuals were cultured, the overexpression and the knockdown vectors of ACSL1 were constructed and transfected into liver cells. The transfection was verified at the mRNA and protein level. Intracellular triglyceride content was quantitatively analyzed using ELISA. Changes of genes related to lipid metabolism were subsequently measured through PCR array. Overexpression of ACSL1 led to higher gene expression and protein levels compared to control and the triglyceride content was significantly increased in overexpressing cells. The expression level of fatty acid oxidation pathway PPARγ was significantly down-regulated compared with the control group, as were genes associated with fatty acid synthesis pathways: SREBP1, ACC, FAS, and SCD1. ACSL1 knockdown decreased the content of triglyceride whereas PPARγ was up-regulated and SREBP1, ACC, FAS, and SCD1 were down-regulated compared with the control group. In summary, high expression of ACSL1 reduced fatty acid ß-oxidation through the PPARγ pathway, thereby increasing triglyceride levels.

Differences in expression of Peroxisome Proliferator-activated Receptor-γ in early-onset preeclampsia and late-onset preeclampsia.

OBJECTIVE: PPARγ is a ligand-binding transcription factor that has been reported to be implicated in lipid metabolism, immune function, and cellular growth and differentiation. It has been suspected to play a role in the pathophysiology of preeclampsia, although the mechanism is yet to be elaborated. This study aims to investigate the expression of PPARγ in early onset preeclampsia (EOPE), late onset preeclampsia (LOPE), and normal pregnancy. We conducted this study using primary trophoblastic cell culture incubated with serum from EOPE, LOPE, and normal pregnancy. The expression of PPARγ in these cells was analyzed using Western Blot. Statistical analysis was performed using one-way ANOVA and Bonferroni's post hoc test. p < 0.05 is considered significant. RESULTS: Serum from normal pregnant women and EOPE did not induce any difference in the expression of PPAR-γ (p > 0.05). In contrast, expression of PPAR-γ was increased in those cells induced by serum from LOPE (p < 0.001). Therefore, we conclude that hypothetically PPAR-γ might play role in the pathophysiology of LOPE but not in EOPE. Other possibility is the activity of PPAR-γ in EOPE is inversely correlated with its expression, therefore the high enzymatic activity of PPAR-γ is tightly regulated by attenuating its expression.

Lansoprazole enhances the antidiabetic effect of dapagliflozin in fortified diet-fed streptozotocin-treated diabetic rats.

Dapagliflozin (DAPA) is used for treating type 2 diabetes, whereas lansoprazole (LPZ) is used as a traditional antiulcer drug. The present study investigated the possible antidiabetic effects of LPZ on fortified diet-fed streptozotocin (FDF/STZ)-induced insulin-resistant diabetic rats. On the basis of the current results, it can be concluded that LPZ could be used as an add-on drug along with the conventional treatment for T2D as it showed beneficial effects in the current experimental model of insulin resistance.

Effects of DHA-enriched fish oil on gene expression levels of p53 and NF-κB and PPAR-γ activity in PBMCs of patients with T2DM: A randomized, double-blind, clinical trial.

BACKGROUND AND AIMS: Omega-3 polyunsaturated fatty acids (PUFAs) are natural peroxisome proliferator-activated receptor gamma (PPAR-γ) ligands. Activated PPAR-γ protects the cardiovascular system against atherosclerotic lesion formation and exerts its anti-inflammatory role by suppressing cytokines induced by nuclear factor kappa-B (NF-κB) in endothelial cells (ECs), and it is hypothesized that apoptosis and cell cycle arrest induced by PPAR-γ ligands may be mediated by the p53-dependent pathway. The aim of our study was to investigate the effects of docosahexaenoic acid (DHA)-enriched fish oil supplement on PPAR-γ activity and mRNA expression levels of p53 and NF-κB. METHODS AND RESULTS: Fifty patients with type 2 diabetes mellitus (T2DM) aged 30-70 years were randomly assigned to receive either 2400 mg/d DHA-rich fish oil or placebo for 8 weeks. Metabolic parameters were assessed at baseline and at the end of the intervention. PPAR-γ activity in the peripheral blood mononuclear cells (PBMCs) was measured using ELISA-based PPAR-γ Transcription Factor Assay Kit, and the gene expression levels of p53 and NF-κB were assessed using real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). On the basis of our finding, 8 weeks of treatment with DHA-rich fish oil increased PPAR-γ activity in PBMCs of subjects with T2DM (p < 0.01) compared to that in placebo (p = 0.4). Between-group comparisons of mean PPAR-γ activity changes showed significant differences (p = 0.03), whereas mRNA expression levels of the p53 and NF-κB genes did not show significant differences between studied groups (p = 0.2 and p = 0.5, respectively). CONCLUSION: Our findings indicated that short-term DHA-rich fish oil supplementation may modulate PPAR-γ activity in PBMCs.

Serum PGE2, 15d-PGJ, PPARγ and CRP levels in patients with schizophrenia.

Many hypotheses have been proposed for the development of schizophrenia, including the one proposing that exogenous and endogenous factors are linked to inflammatory processes. There is strong evidence about the immunological and inflammatory dysfunction in schizophrenia. In this study, we aimed to measure serum 15-deoxy-delta(12,14)-prostaglandin J (15d-PGJ), peroxisome proliferator-activated receptor gamma(PPARγ), prostaglandin E2 (PGE2) and C-reactive protein (CRP) levels. Forty-four patients and 39 healthy volunteers were included in the study. Serum PGE2, 15d-PGJ, PPARγ and CRP levels were measured in both the groups. Demographic data forms were filled out for the patient group, and the Positive and Negative Syndrome Scale, Clinical Global Impression-Severity scale and Calgary Depression scale were used to assess patients' clinical status. Serum PGE2, 15d-PGJ and PPARγ levels were found to be significantly lower in patients with schizophrenia than in healthy controls. There was no significant relationship between the serum PGE2, 15d-PGJ and PPARγ levels and CRP levels.In this study, the evidence of systemic inflammatory conditions in patients with schizophrenia was found. The duration of the disease has been found to be the only variable that independently affects all three biomarker levels in the patients with schizophrenia.

Correlation of serum vitamin D, adipose tissue vitamin D receptor, and peroxisome proliferator-activated receptor γ in women with gestational diabetes mellitus.

BACKGROUND: Gestational diabetes mellitus (GDM) is a common complication during pregnancy. Obesity and overweight are closely related to metabolic diseases and diabetes. However, the role of adipose tissue in the pathogenesis of GDM remains to be studied. The aim of this study was to investigate the correlation of vitamin D (VD) levels, VD receptor (VDR), and peroxisome proliferator-activated receptor γ (PPARγ) expression with GDM in overweight or obese women. METHODS: One hundred and forty pregnant women with full-term single-birth cesarean-section were selected as the study subjects and grouped (70 GDM women, including 35 non-overweight/non-obese women [group G1] and 35 women with overweight or obesity [group G2]; 70 pregnant women with normal glucose tolerance, including 35 non-overweight/non-obese women [group N1] and 35 overweight/obese women [group N2]). The levels of serum VD, blood biochemistry, and adiponectin were compared in these women. Subcutaneous adipose tissue was isolated from the abdominal wall incision. VDR and PPARγ messenger RNA (mRNA) transcript levels in these adipose tissues were quantified by real-time polymerase chain reaction. The differences between the levels of PPARγ protein and phosphorylated PPARγ Ser273 were detected by Western blotting. RESULTS: The serum VD level of GDM women was lower in comparison to that of women with normal glucose tolerance (G1 vs. N1: 20.62 ±â€Š7.87 ng/mL vs. 25.85 ±â€Š7.29 ng/mL, G2 vs. N2: 17.06 ±â€Š6.74 ng/mL vs. 21.62 ±â€Š7.18 ng/mL, P < 0.05), and the lowest in overweight/obese GDM women. VDR and PPARγ mRNA expression was higher in the adipose tissues of GDM women in comparison to that of women with normal glucose tolerance (VDR mRNA: G1 vs. N1: 210.00 [90.58-311.46] vs. 89.34 [63.74-159.92], G2 vs. N2: 298.67 [170.84-451.25] vs. 198.28 [119.46-261.23], PPARγ mRNA: G1 vs. N1: 100.72 [88.61-123.87] vs. 87.52 [66.37-100.04], G2 vs. N2: 117.33 [100.08-149.00] vs. 89.90 [76.95-109.09], P < 0.05), and their expression was the highest in GDM + overweight/obese women. VDR mRNA levels positively correlated with the pre-pregnancy body mass index (BMI), pre-delivery BMI, fasting blood glucose (FBG), homeostasis model assessment of insulin resistance (HOMA-IR), and PPARγ mRNA while it negatively correlated with the VD and the adiponectin levels (r = 0.395, 0.336, 0.240, 0.190, 0.235, -0.350, -0.294, respectively, P < 0.05). The degree of PPARγ Ser273 phosphorylation increased in obese and GDM pregnant women. PPARγ mRNA levels positively correlated with pre-pregnancy BMI, pre-delivery BMI, FBG, HOMA-IR, serum total cholesterol, triglyceride, free fatty acid, and VDR mRNA, while it negatively correlated with the VD and adiponectin levels (r = 0.276, 0.199, 0.210, 0.230, 0.182, 0.214, 0.270, 0.235, -0.232, -0.199, respectively, P < 0.05). CONCLUSIONS: Both GDM and overweight/obese women had decreased serum VD levels and up-regulated VDR and PPARγ mRNA expression in adipose tissue, which was further higher in the overweight or obese women with GDM. VD may regulate the formation and differentiation of adipocytes through the VDR and PPARγ pathways and participate in the occurrence of GDM.

Effects of oral Nigella sativa oil on the expression levels and serum concentrations of adiponectin, PPAR-γ, and TNF-α in overweight and obese women: a study protocol for a crossover-designed, double-blind, placebo-controlled randomized clinical trial.

BACKGROUND: Obesity is a major public health problem in recent decades. The accumulation of excessive fat promotes inflammatory status. Meanwhile, herbal products are marketed for their weight-loss properties, such as Nigella sativa (N. Sativa) which has been used for centuries to treat rheumatoid arthritis, diabetes, and asthma; recently, the anti-obesity characteristics of N. sativa have also been indicated. However, the exact mechanisms and cellular-related pathways are still unclear. Thus, we will aim to assess the effects of oral N. sativa on the gene expression of inflammatory and adipogenesis-related factors, including TNF-α, PPAR-γ, and adiponectin as well as assessing their serum concentrations among obese and overweight individuals. METHODS: Obese and overweight women aged 25-55 years with a body mass index (BMI) of 25-35 kg/m2 will be recruited from the Obesity Clinic in Shahid Sadoughi University of Medical Sciences and will be assessed for eligibility against inclusion criteria. They will be randomly assigned into two groups to receive either two capsules of N. sativa or two capsules of placebo per day for eight weeks (each capsule contains 1000 mg of N. sativa or placebo). There will be a four-week wash-out period and then participants will receive the reverse supplements for another eight weeks. Biochemical assessments and gene expressions (using real-time polymerase chain reaction) will be conducted at the beginning and at the end of every intervention period. DISCUSSION: The present study will investigate the probable cellular pathways for the anti-obesity effects of N. sativa in overweight/obese women. TRIAL REGISTRATION: Iranian Registry of Clinical Trials, IRCT20180528039884N1 . Registered on 2nd of July, 2018.

Assessment of total, ligand-induced peroxisome proliferator activated receptor γ ligand activity in serum.

BACKGROUND: Humans are exposed to a complex mixture of environmental chemicals that impact bone and metabolic health, and traditional exposure assessments struggle to capture these exposure scenarios. Peroxisome proliferator activated receptor-gamma (PPARγ) is an essential regulator of metabolic and bone homeostasis, and its inappropriate activation by environmental chemicals can set the stage for adverse health effects. Here, we present the development of the Serum PPARγ Activity Assay (SPAA), a simple and cost-effective method to measure total ligand activity in small volumes of serum. METHODS: First, we determined essential components of the bioassay. Cos-7 cells were transfected with combinations of expression vectors for human PPARγ and RXRα, the obligate DNA-binding partner of PPARγ, along with PPRE (DR1)-driven luciferase and control eGFP reporter constructs. Transfected cells were treated with rosiglitazone, a synthetic PPARγ ligand and/or LG100268, a synthetic RXR ligand, to characterize the dose response and determine the simplest and most efficacious format. Following optimization of the bioassay, we assessed the cumulative activation of PPARγ by ligands in serum from mice treated with a PPARγ ligand and commercial human serum samples. RESULTS: Cos-7 cells endogenously express sufficient RXR to support efficacious activation of transfected PPARγ. Co-transfection of an RXR expression vector with the PPARγ expression vector did not increase PPRE transcriptional activity induced by rosiglitazone. Treatment with an RXR ligand marginally increased PPRE transcriptional activity in the presence of transfected PPARγ, and co-treatment with an RXR ligand reduced rosiglitazone-induced PPRE transcriptional activity. Therefore, the final bioassay protocol consists of transfecting Cos-7 cells with a PPARγ expression vector along with the reporter vectors, applying rosiglitazone standards and/or 10 µL of serum, and measuring luminescence and fluorescence after a 24 h incubation. Sera from mice dosed with rosiglitazone induced PPRE transcriptional activity in the SPAA in a dose-dependent and PPARγ-dependent manner. Additionally, human serum from commercial sources induced a range of PPRE transcriptional activities in a PPARγ-dependent manner, demonstrating the ability of the bioassay to detect potentially low levels of ligands. CONCLUSIONS: The SPAA can reliably measure total PPRE transcriptional activity in small volumes of serum. This system provides a sensitive, straightforward assay that can be reproduced in any cell culture laboratory.

Effects of Cariprazine, Aripiprazole, and Olanzapine on Mouse Fibroblast Culture: Changes in Adiponectin Contents in Supernatants, Triglyceride Accumulation, and Peroxisome Proliferator-Activated Receptor-γ Expression.

Background and Objectives: The use of the dopamine-partial agonist subclass (also termed dopamine stabilizers) of atypical antipsychotics for the treatment of negative schizophrenia symptoms and some mood disorders has increased recently. Similar to other second-generation antipsychotics (SGAs), aripiprazole (ARI) and cariprazine (CAR) also influence food intake, but the peripheral effects of these drugs on adipose-tissue homeostasis, including adipokine secretion as well as lipo- and adipogenesis, are not fully elucidated. In this study, we explored the adipocyte-related mechanisms induced by second-generation antipsychotics (SGAs), leading to changes in peripheral signals involved in energy homeostasis. Materials and Methods: CAR, a new SGA, was compared with ARI and olanzapine (OLA), using cell cultures to study adipogenesis, and the expression levels of peroxisome proliferator-activated receptor-γ (PPAR-γ) was measured in adipocytes derived from mouse fibroblasts, by western blotting on days 7, 14, and 21 postinduction. The triglyceride (TG) content of the cells was also evaluated on day 15 using Oil Red O staining, and the adiponectin (AN) content in the cell culture supernatants was quantified on days 7 and 15 by enzyme-linked immunosorbent assay. Cells were treated with two concentrations of ARI (0.5 and 20 µg/mL), OLA (1 and 20 µg/mL), and CAR (0.1 and 2 µg/mL). Results: Both concentrations of ARI and OLA, as well as the lower concentration of CAR, significantly increased the TG contents. The AN levels in the supernatants were significantly increased by the higher concentration of ARI on days 7 and 15 (p < 0.05). Although PPAR-γ levels were not significantly affected by ARI and OLA, the lower concentration of CAR induced a significant time-dependent decrease in PPAR-γ expression (p < 0.05). Conclusions: The in vitro adipogenesis considered from TG accumulation, AN secretion, and PPAR-γ expression was differently influenced by ARI, CAR, and OLA. Understanding the adipocyte-related mechanisms of antipsychotics could contribute to understanding their weight-influencing effect.

Natural and Artificial Sweeteners and High Fat Diet Modify Differential Taste Receptors, Insulin, and TLR4-Mediated Inflammatory Pathways in Adipose Tissues of Rats.

It is difficult to know if the cause for obesity is the type of sweetener, high fat (HF) content, or the combination of sweetener and fat. The purpose of the present work was to study different types of sweeteners; in particular, steviol glycosides (SG), glucose, fructose, sucrose, brown sugar, honey, SG + sucrose (SV), and sucralose on the functionality of the adipocyte. Male Wistar rats were fed for four months with different sweeteners or sweetener with HF added. Taste receptors T1R2 and T1R3 were differentially expressed in the tongue and intestine by sweeteners and HF. The combination of fat and sweetener showed an additive effect on circulating levels of GIP and GLP-1 except for honey, SG, and brown sugar. In adipose tissue, sucrose and sucralose stimulated TLR4, and c-Jun N-terminal (JNK). The combination of HF with sweeteners increased NFκB, with the exception of SG and honey. Honey kept the insulin signaling pathway active and the smallest adipocytes in white (WAT) and brown (BAT) adipose tissue and the highest expression of adiponectin, PPARγ, and UCP-1 in BAT. The addition of HF reduced mitochondrial branched-chain amino transferase (BCAT2) branched-chain keto acid dehydrogenase E1 (BCKDH) and increased branched chain amino acids (BCAA) levels by sucrose and sucralose. Our data suggests that the consumption of particular honey maintained functional adipocytes despite the consumption of a HF diet.

The Effects of Probiotic Supplementation on Gene Expression Related to Inflammation, Insulin and Lipid in Patients with Parkinson's Disease: A Randomized, Double-blind, PlaceboControlled Trial.

BACKGROUND: This study was conducted to evaluate the effects of probiotic supplementation on gene expression related to inflammation, insulin and lipid in patients with Parkinson's disease (PD). METHODS: This randomized, double-blind, placebo-controlled clinical trial was conducted in 50 patients with PD as a pilot study. Participants were randomly allocated into two groups to take either 8×109 CFU/day probiotic supplements or placebo (n = 25 each group, one capsule daily) for 12 weeks. Gene expression related to inflammation, insulin, and lipid was quantified in peripheral blood mononuclear cells (PBMC) of PD patients, with RT-PCR method. RESULTS: After the 12-week intervention, compared with the placebo, probiotic intake downregulated gene expression of interleukin-1 (IL-1) (P = 0.03), IL-8 (P < 0.001) and tumor necrosis factor alpha (TNF-α) (P=0.04) in PBMC of subjects with PD. In addition, probiotic supplementation upregulated transforming growth factor beta (TGF-ß) (P = 0.02) and peroxisome proliferatoractivated receptor gamma (PPAR-γ) (P = 0.03) in PBMC of subjects with PD compared with the placebo. We did not observe any significant effect of probiotic intake on gene expression of low-density lipoprotein receptor (LDLR) and vascular endothelial growth factor (VEGF) in PBMC of patients with PD. CONCLUSION: Overall, probiotics supplementation for 12 weeks in PD patients significantly improved gene expression of IL-1, IL-8, TNF-α, TGF-ß and PPAR-γ, but did not affect gene expression of VEGF and LDLR, and biomarkers of inflammation and oxidative stress.

Assessment of potential biomarkers of atherosclerosis in Indian patients with type 2 diabetes mellitus.

BACKGROUND & OBJECTIVES: : Various biological markers of subclinical atherosclerosis have been proposed to predict cardiovascular events in patients with diabetes mellitus (DM). However, there are only a few clinical studies assessing the role of invasive biomarkers [CD-36, peroxisome proliferator-activated receptor gamma (PPAR-γ) and YKL-40] in Indian patients with type 2 DM (T2DM). Hence, the present study was conducted to assess protein levels and gene expression of CD-36, PPAR-γ and YKL-40 in patients with T2DM and compare that with hypertensive and healthy controls. METHODS: : All the participants were subjected to medical history, anthropometric measurements and biochemical and biomarker (ELISA and real-time polymerase chain reaction) estimations. The study groups consisted of patients with T2DM (>5 yr) with hypertension (n=55), patients with T2DM (<2 yr) without hypertension (n=28), hypertensive controls (n=31) and healthy controls (n=30). RESULTS: : Gene expressions of YKL-40 and CD36 were significantly higher in patients with T2DM (>5 yr) with hypertension compared to healthy controls (P=0.006). In addition, a significant increase in serum levels of sCD36, PPAR-γ and YKL-40 was observed in patients with T2DM (>5 yr) with hypertension compared to healthy controls (P< 0.05). Serum levels as well as gene expression of CD36 showed significant correlation with serum levels as well as gene expression of PPAR-γ (ρ=0.45 and ρ=0.51; P< 0.001), respectively. INTERPRETATION & CONCLUSIONS: : CD36 and YKL-40 may be potential inflammatory biomarkers for early onset of atherosclerosis in patients with T2DM.