Peroxisome Proliferator-Activated Receptor-γGene Expression and Its Association with Oxidative Stress in Patients with Metabolic Syndrome

The effect of evening primrose oil (Oenothera biennis) on the level of adiponectin and some biochemical parameters in rats with fructose induced metabolic syndrome

The effect of evening primrose oil on adiponectin level and some biochemical parameters in model of fructose-induced metabolic syndrome were investigated. The rats were divided into 4 groups: control, evening primrose oil, fructose, fructose + evening primrose oil. Body weight, daily feed and water consumptions and systolic blood pressures of animals were measured. At the end of trial, blood samples were taken, livers were excised and histopathological examination was performed. Glucose, uric acid, triglyceride, T.cholesterol, LDL, HDL, VLDL, ALT, AST, ALP, LDH, adiponectin, insulin, IL-6, TNF-α, TAC, and TOS levels were analysed. Some analysed parameters and systolic blood pressure of fructose + evening primrose oil group decreased significantly compared to fructose group and adiponectin, TAC, and HDL levels were significantly increased. As conclusion, evening primrose oil can be considered as antioxidant agent by reducing oxidative stress, increasing adiponectin levels and insulin sensitivity, anti-inflammatory properties, exhibiting anti-atherogenic effect by regulating dyslipidemia and systolic blood pressure.

Production of Reactive Oxygen Species by Epicardial Adipocytes Is Associated with an Increase in Postprandial Glycemia, Postprandial Insulin, and a Decrease in Serum Adiponectin in Patients with Severe Coronary Atherosclerosis

Purpose. This work investigates the relations between the production of reactive oxygen species (ROS) by epicardial adipose tissue (EAT) adipocytes and parameters of glucose/insulin metabolism, circulating adipokines levels, and severity of coronary atherosclerosis in patients with coronary artery disease (CAD); establishing significant determinants describing changes in ROS EAT in this category of patients. Material and methods. This study included 19 patients (14 men and 5 women, 53−72 y.o., 6 patients with diabetes mellitus type 2; 5 patients with prediabetes), with CAD, who underwent coronary artery bypass graft surgery. EAT adipocytes were isolated by the enzymatic method from intraoperative explants obtained during coronary artery bypass grafting. The size of EAT adipocytes and ROS level were determined. Results. The production of ROS by EAT adipocytes demonstrated a direct correlation with the level of postprandial glycemia (rs = 0.62, p < 0.05), and an inverse correlation with serum adiponectin (rs = −0.50, p = 0.026), but not with general and abdominal obesity, EAT thickness, and dyslipidemia. Regression analysis demonstrated that the increase in ROS of EAT adipocytes occurs due to the interaction of the following factors: postprandial glycemia (β = 0.95), postprandial insulin (β = 0.24), and reduced serum adiponectin (β = −0.20). EAT adipocytes in patients with diabetes and prediabetes manifested higher ROS production than in patients with normoglycemia. Although there was no correlation between the production of ROS by EAT adipocytes and Gensini score in the total group of patients, higher rates of oxidative stress were observed in EAT adipocytes from patients with a Gensini score greater than median Gensini score values (≥70.55 points, Gr.B), compared to patients with less severe coronary atherosclerosis (<70.55 points, Gr.A). Of note, the frequency of patients with diabetes and prediabetes was higher among the patients with the most severe coronary atherosclerosis (Gr.B) than in the Gr.A. Conclusions. Our data have demonstrated for the first time that systemic impairments of glucose/insulin metabolism and a decrease in serum adiponectin are significant independent determinants of oxidative stress intensity in EAT adipocytes in patients with severe coronary atherosclerosis. The possible input of the interplay between oxidative stress in EAT adipocytes and metabolic disturbances to the severity of coronary atherosclerosis requires further investigation.

Effects of Nigella sativa supplementation on blood concentration and mRNA expression of TNF-α, PPAR-γ and adiponectin, as major adipogenesis-related markers, in obese and overweight women: a crossover, randomised-controlled trial

Adipocyte expansion through adipogenesis can offset the adverse metabolic effects of obesity. Nigella sativa (NS) (black seed) oil is shown to have therapeutic features in the management of obesity. NS oil might have beneficial changes in obese populations through mediating serum levels of adipogenesis-related parameters and relative transcriptional gene-diet interactions (nutrigenomics), though no previous studies assessed this mechanism in overweight/obese participants. This study assessed the effects of NS oil supplements on blood concentration and mRNA expression levels of TNF-α, PPAR-γ and serum adiponectin and expression of AdipoR1, as major adipogenesis and obesity-related parameters, in overweight/obese women using a cross-over design. Eligible women were randomised to receive either NS oil supplements (2000 mg/d) or placebo. Two periods of interventions (8 weeks in each) were cross-changed by a 4-week washout period. An individualised diet plan without calorie deficits was given to participants to match their energy/macronutrient intakes. The Pkcross procedure and intention-to-treat analysis were performed using Stata. Cohen's d(d) was estimated to measure the magnitude of the effects. Forty-six participants were included. NS oil capsules reduced transcription levels ((d = -2·31), P < 0·001) and blood concentrations of TNF-α ((d = -0·29), P < 0·001). AdipoR1 expression (d = 2·24, P < 0·001) and serum adiponectin (d = 0·88, P < 0·001) showed a significant augmentation with a medium-high effect size, as did gene expression (d = 0·69, P < 0·001) and serum levels of PPAR-γ (d = 0·97, P < 0·001). There was a moderate but significant decrease in body weight (d = 0·6, P < 0·001). The present beneficial findings would provide strong information for future nutrigenomics/clinical trial studies assessing the role of NS in the management of obesity and other comorbidities.

Impact of ibuprofen and peroxisome proliferator-activated receptor gamma on emotion-related neural activation: A randomized, placebo-controlled trial

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen have shown initial promise in producing antidepressant effects. This is perhaps due to these drugs being peroxisome proliferator-activated receptor gamma (PPARγ) agonists, in addition to their inhibition of cyclooxygenase enzymes. Some, albeit mixed, evidence suggests that PPARγ agonists have antidepressant effects in humans and animals. This double-blind, placebo-controlled, pharmacologic functional magnetic resonance imaging (ph-fMRI) study aimed to elucidate the impact of ibuprofen on emotion-related neural activity and determine whether observed effects were due to changes in PPARγ gene expression. Twenty healthy volunteers completed an emotional face matching task during three fMRI sessions, conducted one week apart. Placebo, 200 mg, or 600 mg ibuprofen was administered 1 h prior to each scan in a pseudo-randomized order. Peripheral blood mononuclear cells were collected at each session to isolate RNA for PPARγ gene expression. At the doses used, ibuprofen did not significantly change PPARγ gene expression. Ibuprofen dose was associated with decreased blood oxygen level-dependent (BOLD) activation in the dorsolateral prefrontal cortex and fusiform gyrus during emotional face processing (faces-shapes). Additionally, PPARγ gene expression was associated with increased BOLD activation in the insula and transverse and superior temporal gyri (faces-shapes). No interaction effects between ibuprofen dose and PPARγ gene expression on BOLD activation were observed. Thus, results suggest that ibuprofen and PPARγ may have independent effects on emotional neurocircuitry. Future studies are needed to further delineate the roles of ibuprofen and PPARγ in exerting antidepressant effects in healthy as well as clinical populations.

Association of PPARγ gene expression with postprandial hypertriglyceridaemia and risk of type 2 diabetes mellitus

PURPOSE

Peroxisome proliferator-activated receptor γ (PPARγ) gene is strongly associated with type 2 diabetes mellitus, as well as postprandial lipemia, and plays an important role in Wnt dependent adipogenesis in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). We aimed to study the expression of PPARγ gene in SAT and VAT to find out its correlation with postprandial hypertriglyceredemia and glucose intolerance.

METHODS

Thirty subjects who were scheduled to undergo abdominal surgery were recruited in three groups (n = 10 in NGT, n = 10 in prediabetes, and n = 10 in T2DM). A standardized oral fat challenge was performed. Anthropometry, plasma glucose, HbA1c, and fasting serum insulin were also measured. SAT and VATs were collected during surgery for PPARγ gene expression studies by real-time PCR.

RESULTS

PPARγ gene expression was 5.5-fold lower in T2DM and 1.7-fold lower in prediabetes as compared with NGT subjects in VAT. There was a significant negative correlation of expression of PPARγ gene in VAT {Tgauc (r = -0.57, p < 0.007), Peak Tg (r = -0.51, p < 0.01)} as well as in subcutaneous adipose tissue {Tgauc (r = -0.45, p < 0.02)} with PPTg responses measures.

CONCLUSION

Reduced adipocyte expression of PPARγ gene and the resultant postprandial hypertriglyceredemia is associated with greater risk of diabetes and prediabetes.

The implication of hepatokines in metabolic syndrome

Hepatokines are liver-derived proteins with equivocal roles in metabolic syndrome (MetS). These proteins have prominent role in pathogenesis of MetS component such as obesity, insulin resistance, dyslipidemia and hypertension. The identification and functional characterization of hepatokines may provide significant insights that could help in better understanding of MetS pathogenesis. Fetuin-A, Hepatocyte-derived fibrinogen-related protein 1, Fibroblast growth factor 21, Angiopoietin-related growth factor, Selenoprotein-P, Angiopoietin like proteins, Leukocyte cell-derived chemotaxin 2 are regarded as the most significant hepatokines. We describe recent data on these new hormones in progression of MetS. Understanding of the accurate role of these proteins in pathophysiology of MetS can help improving prevention and treatment of this syndrome.

Is oxidative stress of adipocytes a cause or a consequence of the metabolic syndrome?

Metabolic syndrome is accompanied by oxidative stress in animals and humans. The main source of ROS in experimental metabolic syndrome is NADPH oxidase and possibly adipocyte mitochondria. It is now documented that oxidative stress induces insulin resistance of adipocytes and increases secretion of leptin, MCP-1, IL-6, and TNF-α by adipocytes. It was established that oxidative stress induces a decrease in adiponectin production by adipocytes. It has also been shown that obesity itself can induce oxidative stress. Oxidative stress can cause an alteration of intracellular signaling in adipocytes that apparently leads to the formation of insulin resistance of adipocytes. Chronic stress, glucocorticoids, mineralocorticoids, angiotensin-II, TNF-α also play an important role in the pathogenesis of oxidative stress of adipocytes. Oxidative stress is not only a consequence of metabolic syndrome, but also a reason and a foundational link in the pathogenesis of the metabolic syndrome.

Autophagy as an emerging target in cardiorenal metabolic disease: From pathophysiology to management

Although advances in medical technology and health care have improved the early diagnosis and management for cardiorenal metabolic disorders, the prevalence of obesity, insulin resistance, diabetes, hypertension, dyslipidemia, and kidney disease remains high. Findings from numerous population-based studies, clinical trials, and experimental evidence have consolidated a number of theories for the pathogenesis of cardiorenal metabolic anomalies including resistance to the metabolic action of insulin, abnormal glucose and lipid metabolism, oxidative and nitrosative stress, endoplasmic reticulum (ER) stress, apoptosis, mitochondrial damage, and inflammation. Accumulating evidence has recently suggested a pivotal role for proteotoxicity, the unfavorable effects of poor protein quality control, in the pathophysiology of metabolic dysregulation and related cardiovascular complications. The ubiquitin-proteasome system (UPS) and autophagy-lysosomal pathways, two major although distinct cellular clearance machineries, govern protein quality control by degradation and clearance of long-lived or damaged proteins and organelles. Ample evidence has depicted an important role for protein quality control, particularly autophagy, in the maintenance of metabolic homeostasis. To this end, autophagy offers promising targets for novel strategies to prevent and treat cardiorenal metabolic diseases. Targeting autophagy using pharmacological or natural agents exhibits exciting new strategies for the growing problem of cardiorenal metabolic disorders.

PPARγ provides anti-inflammatory and protective effects in intrahepatic cholestasis of pregnancy through NF-κB pathway

AIMS

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific hepatic disorder with potentially deleterious consequences of fetuses. Although the intimate relationship between ICP and peroxisome proliferator-activated receptor γ (PPARγ) has been previously reported in physiological and pathological conditions, the detailed mechanisms in the process of intrahepatic cholestasis of pregnancy has been unclear. The aims of this study are to assess the role of PPARγ regulating the reactive oxygen species (ROS) and inflammation in the process of the ICP.

METHODS

Clinical data of the pregnant women were collected. And the serum of cytokines, hepatic function, the expression of PPARγ and NF-κB were measured. The rat and fetal rat ICP model were constructed and detection of the expression of PPARγ and NF-κB, evaluation the level of ROS and inflammation.

RESULTS

The clinical data showed that the new-born information in severe ICP group were significantly different as compared to that in control group (P < 0.05), and part of information in mild ICP group were also difference to that in control group (P < 0.05). The expression of PPARγ and NF-κB were significantly higher in clinical pregnant women, rat, fetal rat ICP model groups and taurocholate acid (TCA) treated HTR-8/SVneo cell (P < 0.01). PPARγ inhibited the production of ROS and decreased the level of inflammation. PPARγ down-regulated the NF-κB pathway.

CONCLUSIONS

PPARγ provides the anti-inflammatory and protective effects in intrahepatic cholestasis of pregnancy through NF-κB pathway, which might be a probably one of the mechanisms of ICP.

Role of Red Cell Distribution Width in the Relationship between Clinical Outcomes and Anticoagulation Response in Patients with Atrial Fibrillation

Little is known as to why elevated red cell distribution width (RDW) is associated with adverse clinical outcomes in patients with atrial fibrillation (AF). We hypothesized that RDW value might predict the intensity of anticoagulation, resulting in higher adverse events in patients with AF taking warfarin. We analyzed 657 patients with non-valuvular AF who took warfarin. The intensity of anticoagulation was assessed as mean time in the therapeutic range (TTR) and defined TTR ≥60% as an optimal intensity. The primary end-point was the composite of stroke/systemic embolism and major bleeding. The secondary end-point was the composite of stroke/systemic embolism, major bleeding and death. The relationship between the baseline RDW with TTR and clinical outcomes was assessed using categorical variables as quartiles or dichotomous variables. The mean value of TTR decreased as an increment of the RDW (45.2% vs. 44.7% vs. 40.8% vs. 35.2%, p<0.001). Primary and secondary end-points were significantly increased when TTR was less than 60% and RDW was more than 13.6%. Ratio of patients achieving optimal anticoagulation were significantly decreased as an increment of RDW. A RDW of ≥13.6% was a significant predictor for poor anticoagulation control (adjusted Odds ratio [OR] 0.43, 95% confidence interval [CI] 0.23–0.82), stroke (adjusted hazard ratio [HR] 3.86, 95% CI 1.11–13.40), primary (adjusted HR 1.88, 95% CI 1.12–3.16) and secondary end-point (adjusted HR 2.46, 95% CI 1.26–4.81). RDW was negatively associated with TTR in patients with AF. Therefore, RDW might be a useful marker for the prediction of anticoagulation response and clinical outcomes in patients with AF.