Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0028754 (obesity)
 124,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Peroxisome proliferator-activated receptors (PPARs) were discovered over a decade ago, and were classified as orphan members of the nuclear receptor superfamily. To date, three PPAR subtypes have been discovered and characterized (PPAR $\alpha$, $\beta/\delta$, $\gamma$ ). Different PPAR subtypes have been shown to play crucial roles in important diseases and conditions such as obesity, diabetes, atherosclerosis, cancer, and fertility. Among the most studied roles of PPARs is their involvement in inflammatory processes. Numerous studies have revealed that agonists of PPAR $\alpha$ and PPAR $\gamma$ exert anti-inflammatory effects both in vitro and in vivo. Using the carrageenan-induced paw edema model of inflammation, a recent study in our laboratories showed that these agonists hinder the initiation phase, but not the late phase of the inflammatory process. Furthermore, in the same experimental model, we recently also observed that activation of PPAR $\delta$ exerted an anti-inflammatory effect. Despite the fact that exclusive dependence of these effects on PPARs has been questioned, the bulk of evidence suggests that all three PPAR subtypes, PPAR $\alpha, \delta, \gamma$, play a significant role in controlling inflammatory responses. Whether these subtypes act via a common mechanism or are independent of each other remains to be elucidated. However, due to the intensity of research efforts in this area, it is anticipated that these efforts will result in the development of PPAR ligands as therapeutic agents for the treatment of inflammatory diseases.
 ...
PMID:Role of Peroxisome Proliferator-Activated Receptors in Inflammation Control. 1529 82

Polycystic ovary syndrome (PCOS) is one of the most common endocrine metabolic diseases and is characterized by obesity in approximately 50% of those affected. Adiponectin is an adipocyte-derived protein that possesses an antiatherosclerotic action and improves insulin sensitivity. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) regulates the transcription of several adipocyte-specific genes. The aim of this study was to investigate the putative influence of the PPAR-gamma gene Pro12Ala polymorphism on the adiponectin levels in PCOS and healthy women. One hundred twenty women with PCOS and 120 healthy women whose ages and body mass indexes matched those of the PCOS patients were investigated. The genetic analysis of PPAR-gamma gene Pro12Ala polymorphism was performed by restriction fragment of polymorphisms. Serum adiponectin levels were evaluated, and the homeostasis model assessment score was also calculated. No subject was homozygous for the Ala12 allele of the PPAR-gamma gene. No significant differences in body mass index, plasma glucose and lipid levels, and homeostasis model assessment scores were observed between and within genotype groups in PCOS and control women. No significant differences in serum adiponectin concentrations were observed between and within genotype groups in PCOS and control women. In conclusion, our results confirm that adiponectin concentrations are similar in PCOS and controls and demonstrate no effect of the PPAR-gamma gene Pro12Ala polymorphism on serum adiponectin levels.
 ...
PMID:Lack of an association between peroxisome proliferator-activated receptor-gamma gene Pro12Ala polymorphism and adiponectin levels in the polycystic ovary syndrome. 1547 14

Peroxisome proliferator-activated receptor (PPAR)-alpha is a ligand-activated transcriptional factor that belongs to the family of nuclear receptors. PPAR-alpha regulates the expression of genes involved in fatty acid beta-oxidation and is a major regulator of energy homeostasis. Fibrates are PPAR-alpha agonists and have been used to treat dyslipidemia for several decades because of their triglyceride (TG) lowering and high-density lipoprotein cholesterol (HDL-C) elevating effects. More recent research has demonstrated anti-inflammatory and anti-thrombotic actions of PPAR-alpha agonists in the vessel wall as well. Thus, PPAR-alpha agonists decrease the progression of atherosclerosis by modulating metabolic risk factors and by their anti-inflammatory actions on the level of the vascular wall. This is confirmed by several clinical studies, in which fibrates have shown to reduce atherosclerotic plaque formation and the event rate of coronary heart disease (CHD), especially in patients suffering from metabolic syndrome (MS). MS is characterized by a group of metabolic risk factors that include obesity, raised blood pressure, dyslipidemia, insulin resistance or glucose intolerance, and a prothrombotic state, and its incidence in the Western world is rising to epidemic proportions. This review paper will focus on the functions of PPAR-alpha in fatty acid beta-oxidation, lipid metabolism, and vascular inflammation. Furthermore, PPAR-alpha genetics, the clinical use of PPAR-alpha activators and their future perspective will be discussed.
 ...
PMID:Peroxisome proliferator-activated receptor (PPAR)-alpha: a pharmacological target with a promising future. 1549 75

Peroxisome proliferator-activated receptor (PPAR) agonists have long been used for the treatment of diabetes and hypercholesterolemia--disorders that give individuals a high predisposition for cardiovascular disease. Prevention of the onset of the latter can begin when a diagnosis of metabolic syndrome, a pathology that groups glucose and lipid disturbances, is made. Although the characteristic components of metabolic syndrome (ie, high blood pressure, obesity, dyslipidemia, insulin resistance and proinflammatory state) are likely to improve through a radical change in lifestyle, a therapeutic approach is also advisable, and the PPAR agonists are the first in a growing list of drugs that may be effective in the prevention of the development of cardiovascular disease.
 ...
PMID:PPARs as targets for the modulation of cardiovascular risk factors associated with the metabolic syndrome. 1550 47

Peroxisome proliferator-activated receptor-gamma (PPARgamma) has been hypothesized as being involved in colorectal cancer given its role in adipocyte development and insulin resistance. In this study we evaluated the association between the Pro12Ala (P12A) PPARgamma polymorphism and body mass index (BMI), waist-to-hip ratio (WHR), physical activity level, and energy intake and risk of colorectal cancer using data from a population-based, case-control study of colon cancer (1,577 cases and 1,971 controls) and rectal cancer (794 cases and 1,001 controls). We further evaluated how the P12A PPARgamma polymorphism is associated with obesity and fat pattern in the control population. The odd ratio for PPARgamma PA or AA genotype relative to the PP genotype for colon cancer was 0.9 (95% confidence interval, CI=0.8-1.0) and for rectal cancer was 1.2 (95% CI=1.0-1.5) adjusting for race, age, and sex. P12A PPARgamma did not significantly interact with BMI, WHR, energy intake, and energy expenditure to alter risk of colon or rectal cancer. Furthermore, the P12A PPARgamma polymorphism was not associated with obesity or WHR in the control population; it did not interact with energy intake or energy expenditure to alter risk of obesity or large WHR. These data do not support the hypothesis that the P12A PPARgamma polymorphism is associated with colon or rectal cancer through regulation of energy balance.
 ...
PMID:PPARgamma, energy balance, and associations with colon and rectal cancer. 1586 Apr 37

Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand--activated transcription factors. Three PPAR isoforms , designated PPARalpha, -beta/delta, and -gamma, have been identified and attracted enormous attention due to the key role these receptors play in regulating adipogenesis, lipid metabolism, insulin sensitivity, inflammation and blood pressure. Growing evidence points to a causative relationship between PPAR activity and the metabolic syndrome, including insulin resistance, glucose intolerance or type II diabetes, obesity, dyslipidemia, hypertension, atherosclerosis, and albuminuria. Importantly, both PPARalpha activators such as fibric acid class of hypolipidemic drugs and PPARgamma agonists including antidiabetic thiazolidinediones (TZDs) have been proved to be effective for improving metabolic syndrome. All three PPAR isoforms appear to play important roles in the development of type II diabetes and diabetic nephropathy. Accumulating data has begun to emerge suggesting PPARs may serve as potential therapeutic targets for treating the metabolic syndrome and its related complications. Here we review the literature pertaining to the action, ligand selectivity and physiological role of PPARs. Particular emphasis is placed on their pathogenic roles in the metabolic syndrome and the therapeutic utility of PPAR modulators in the treatment of type II diabetes.
 ...
PMID:[PPAR family and its relationship to metabolic syndrome]. 1588 36

Aging is associated with a metabolic decline characterized by the development of changes in fat distribution, obesity, and insulin resistance. Dysfunctional humoral and cell-mediated immune responses occur with age, and these aberrations have been implicated in the increased incidence of infectious diseases, hyporesponsiveness to vaccination, and the etiology of numerous chronic degenerative diseases. All these metabolic and immune alterations are associated with a variety of age-related diseases that subsequently result in increased mortality. Leptin can modulate many of the metabolic alterations characteristic of aging. Leptin resistance has been implicated in the pathogenesis of obesity-related complications involving abnormalities of lipid metabolism that resemble those of old age. Increased plasma leptin levels with aging suggest resistance to leptin action and may explain why elderly subjects have abdominal obesity and insulin resistance. Leptin's failure may be considered for the metabolic decline seen with aging. Peroxisome proliferator-activated receptor (PPAR)-alpha, the transcription factor for the mitochondrial and peroxisomal enzymes of beta-oxidation, and its target enzymes, are upregulated by hyperleptinemia. PPARalpha has been shown to mediate the action of the hypolipidemic drugs of the fibrate class on lipid and lipoprotein metabolism. PPARalpha activators furthermore improve glucose homeostasis and influence body weight and energy homeostasis. The administration of agents capable of activating the PPARalpha was found to restore the cellular redox balance, evidenced by a lowering of tissue lipid peroxidation, an elimination of constitutively active NF-kappaB, loss in spontaneous inflammatory cytokine production, and ailing in the aging immunity.
 ...
PMID:PPARalpha activators may be good candidates as antiaging agents. 1589 14

Insulin resistance is frequently accompanied by obesity and both obesity and type 2 diabetes are associated with a mild chronic inflammation. Elevated levels of various cytokines, such as TNF-alpha and IL-6, are typically found in the adipose tissue in these conditions. It has been suggested that many cytokines produced in the adipose tissue are derived from infiltrated inflammatory cells. However, the adipose tissue itself has proven to be an important endocrine organ, secreting several hormones and cytokines, usually referred to as adipokines. Peroxisome proliferator-activated receptor (PPAR)gamma is essential for adipocyte proliferation and differentiation. In recent years, PPARgamma and its ligands, the thiazolidinediones (TZD), have achieved great attention due to their insulin sensitizing and anti-inflammatory properties. Treatment with TZDs result in improved insulin signaling and adipocyte differentiation, increased adipose tissue influx of free fatty acids and inhibition of cytokine expression and action. As a result, PPARgamma plays a central role in maintaining a functional and differentiated adipose tissue.
 ...
PMID:The effect of PPARgamma ligands on the adipose tissue in insulin resistance. 1593 83

Salacia oblonga (SO) root is an Ayurvedic medicine with anti-diabetic and anti-obese properties. Peroxisome proliferator-activated receptor (PPAR)-alpha, a nuclear receptor, plays an important role in maintaining the homeostasis of lipid metabolism. Here, we demonstrate that chronic oral administration of the water extract from the root of SO to Zucker diabetic fatty (ZDF) rats, a genetic model of type 2 diabetes and obesity, lowered plasma triglyceride and total cholesterol (TC) levels, increased plasma high-density lipoprotein levels and reduced the liver contents of triglyceride, non-esterified fatty acids (NEFA) and the ratio of fatty droplets to total tissue. By contrast, the extract had no effect on plasma triglyceride and TC levels in fasted ZDF rats. After olive oil administration to ZDF the extract also inhibited the increase in plasma triglyceride levels. These results suggest that SO extract improves postprandial hyperlipidemia and hepatic steatosis in ZDF rats. Additionally, SO treatment enhanced hepatic expression of PPAR-alpha mRNA and protein, and carnitine palmitoyltransferase-1 and acyl-CoA oxidase mRNAs in ZDF rats. In vitro, SO extract and its main component mangiferin activated PPAR-alpha luciferase activity in human embryonic kidney 293 cells and lipoprotein lipase mRNA expression and enzyme activity in THP-1 differentiated macrophages; these effects were completely suppressed by a selective PPAR-alpha antagonist MK-886. The findings from both in vivo and in vitro suggest that SO extract functions as a PPAR-alpha activator, providing a potential mechanism for improvement of postprandial hyperlipidemia and hepatic steatosis in diabetes and obesity.
 ...
PMID:Salacia oblonga root improves postprandial hyperlipidemia and hepatic steatosis in Zucker diabetic fatty rats: activation of PPAR-alpha. 1597 14

Cardiovascular disease (CVD) remains the leading cause of mortality in developed countries. Several risk factors are associated with CVD, including type 2 diabetes, obesity, insulin resistance, dyslipidaemia and hypertension. Different pharmacological therapies have been developed to control these risk factors. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors, which belong to the nuclear receptor superfamily that controls lipid and glucose metabolism as well as inflammatory risk factors for CVD. PPARalpha agonists, such as the fibrates, correct dyslipidaemia, thus decreasing CVD risk. PPARgamma agonists, such as the glitazones, increase insulin sensitivity and decrease plasma glucose levels in patients with diabetes. Moreover, both PPARalpha and PPARgamma agonists exert anti-inflammatory activities in liver, adipose and vascular tissues. In this review, we focus on the mode of action of PPARalpha and PPARalpha agonists, illustrating the potential of the newly developed dual PPAR agonists for the treatment of global risk in patients with the metabolic syndrome or type 2 diabetes.
 ...
PMID:Inflammation, dyslipidaemia, diabetes and PPars: pharmacological interest of dual PPARalpha and PPARgamma agonists. 1603 93


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>