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)

The utilization of L-alanine by liver is dependent on amino acid uptake from blood. This uptake, mainly mediated by the A transport system, may be regulated by different nutritional and physiologic conditions. The regulation of this transport system by diets with different protein content was tested in lean and obese Zucker rats. High-protein (HP) and low-protein (LP) diets led to changes in the rats' growth patterns, especially in lean animals. However, homeostasis was relatively well maintained, as seen in plasma values, in spite of the increased urea production in the HP groups and increased triacylglycerides in the LP groups. The obese animals took up L-alanine at a higher rate than the lean animals. Obesity led to the emergence of a high-affinity component (K(M) approximately 0.1-0.2 mM) in the transport system, which was not dependent on the protein content of the diet. This component has a 10-fold increase in affinity for L-alanine, but with an approximately 3- to 5-fold reduction in maximal velocity of transport.
 ...
PMID:The hepatic amino acid system A transport activity, is up-regulated in obese Zucker rats. 1553 71

Interleukin-6 (IL-6) is a pleiotropic cytokine involved in the pathophysiology of various human diseases such as type 2 diabetes and obesity. IL-6 signals via a heterodimeric receptor complex consisting of a soluble IL-6 alpha-subunit (IL-6 receptor [IL6R]) and a signal transducing subunit (gp130). The IL6R gene maps to an important candidate locus for type 2 diabetes on chromosome 1q21. An Asp358Ala polymorphism of the IL6R has been reported to associate with obesity in Pima Indians. We investigated the Asp358Ala polymorphism in relation to type 2 diabetes, obesity, and other pre-diabetic quantitative traits among Danish whites. By applying a recessive genetic model in a case-control study of 1,349 type 2 diabetic patients and 4,596 glucose-tolerant control subjects, we found a significant difference in genotype distribution (P = 0.008) and in allele frequency (Ala-allele 38.3% [95% CI 36.5-40.1] in diabetic subjects vs. 41.2% [40.2-42.2] in control subjects; P = 0.007). The odds ratio for the Asp/Asp carriers versus Ala/Ala carriers was 1.38 (1.09-1.71). Among 4,251 middle-aged glucose-tolerant subjects, the Asp358Ala polymorphism was not associated with estimates of obesity, post-oral glucose tolerance test serum insulin release, or the homeostasis model assessment of insulin resistance index. In conclusion, the Asp358Ala polymorphism of the IL6R associates with type 2 diabetes in Danish whites.
 ...
PMID:Variation in the interleukin-6 receptor gene associates with type 2 diabetes in Danish whites. 1556 70

The agouti-related protein (AGRP) is an endogenous antagonist of the centrally expressed melanocortin receptors. The melanocortin-4 receptor (MC4R) is involved in energy homeostasis, food intake, sexual function, and obesity. The endogenous hAGRP protein is 132 amino acids in length, possesses five disulfide bridges at the C-terminus of the molecule, and is expressed in the hypothalamus of the brain. We have previously reported that a monocyclic hAGRP(103-122) peptide is an antagonist at the melanocortin receptors expressed in the brain. Stereochemical inversion from the endogenous l- to d-isomers of single or multiple amino acid modifications in this monocyclic truncated hAGRP sequence resulted in molecules that are converted from melanocortin receptor antagonists into melanocortin receptor agonists. The Asp-Pro-Ala-Ala-Thr-Ala-Tyr-cyclo[Cys-Arg-DPhe-DPhe-Asn-Ala-Phe-Cys]-Tyr-Ala-Arg-Lys-Leu peptide resulted in a 60 nM melanocortin-1 receptor agonist that is 100-fold selective versus the mMC4R, 1000-fold selective versus the mMC3R, and ca. 180-fold selective versus the mMC5R. In attempts to identify putative ligand-receptor interactions that may be participating in the agonist induced stimulation of the MC4R, selected ligands were docked into a homology molecular model of the mMC4R. These modeling studies have putatively identified hAGRP ligand DArg111-mMC4RAsn115 (TM3) and the hAGRP DPhe113-mMC4RPhe176 (TM4) interactions as important for agonist activity.
 ...
PMID:Stereochemical studies of the monocyclic agouti-related protein (103-122) Arg-Phe-Phe residues: conversion of a melanocortin-4 receptor antagonist into an agonist and results in the discovery of a potent and selective melanocortin-1 agonist. 1561 19

We investigated the relationship between Ala54Thr variant allele of the fatty acid-binding protein 2 (FABP2) gene (Ala54Thr) and development of obesity in Japanese obese women. FABP2 genotypes were determined with a fluorescent allele-specific DNA primer assay system. Body weight, waist and hip circumference, amounts of visceral and subcutaneous white adipose tissue measured by computed tomography (CT) were compared between subjects with Thr allele and without Thr allele before and after the diet and exercise therapy in 80 Japanese obese women. The frequency of the Thr54 allele did not differ between obese and control subjects (0.388 versus 0.329, respectively). In subjects with Ala/Thr and Thr/Thr genotype, adjusted resting metabolic rate (RMR) was significantly lower than the subjects with Ala/Ala genotype. Subjects with the Thr54 allele showed significantly greater waist circumference after diet and exercise therapy than subjects with Ala/Ala genotype. They also demonstrated greater body weight at 20 years of age compared to subjects with Ala/Ala genotype. In conclusion, Thr54 allele of FABP2 has associations with lower adjusted resting metabolic rate, resistance in reducing visceral white adipose tissue (WAT) and early onset of obesity in Japanese obese women.
 ...
PMID:Thr54 allele of the FABP2 gene affects resting metabolic rate and visceral obesity. 1562 Apr 32

Expression of the agouti signaling protein (ASIP) during hair growth produces the red/yellow pigment pheomelanin. ASIP, and its neuropeptide homolog the agouti-related protein (AgRP) involved in energy balance, are novel, paracrine signaling molecules that act as inverse agonists at distinct subsets of melanocortin receptors. Ubiquitous ASIP expression in mice gives rise to a pleiotropic phenotype characterized by a uniform yellow coat color, obesity, overgrowth, and metabolic derangements similar to type II diabetes in humans. Here we report the synthesis and NMR structure of ASIP's active, cysteine-rich, C-terminal domain. ASIP adopts the inhibitor cystine knot fold and, along with AgRP, are the only known mammalian proteins in this structure class. Moreover, ASIP populates two distinct conformers resulting from a cis peptide bond at Pro102-Pro103 and a coexistence of cis/trans isomers of Ala104-Pro105. Pharmacologic studies of Pro-->Ala mutants demonstrate that the minor conformation with two cis peptide bonds is responsible for activity at all MCRs. The loop containing the heterogeneous Ala-Pro peptide bond is conserved in mammals, and suggests that ASIP is either trapped by evolution in this unusual configuration or possesses function outside of strict MCR antagonism.
 ...
PMID:Structures of the agouti signaling protein. 1570 17

The aim of this study was to evaluate the correlation of ultrasonography-proven fatty liver with liver functions, serum lipid levels and anthropometric measurements in children with exogenous obesity. Three hundred and twenty-two patients (183 girls, 56.8%) with a mean age of 11.4+/-3.2 years (4-18 years) who presented with the complaint of obesity were enrolled. In 38 (11.8%) patients, increased liver echogenicity resembling fatty liver was found (Group 1). The body mass index percentages of group 1 patients were significantly higher than of those without fatty liver (Group 2) (157.7+/-18.0 vs 151.3+/-17.8, p=0.038). Alanine and aspartate aminotransferase levels of group 1 patients were significantly higher than of group 2 (p=0.002 vs p=0.028, respectively). Triglyceride levels were significantly higher in group 1 patients (120.8+/-88.8 vs 100.5+/-58.5 mg/dl, p=0.044). In conclusion, ultrasonography is an easy and noninvasive method for the diagnosis of fatty liver in children with obesity. Body mass index and serum lipids were higher in group 1 patients. The diagnosis and early treatment of obesity in childhood is important for the prevention and better treatment of related complications. Thus, ultrasonography should be a part of the early evaluation of obese children.
 ...
PMID:Fatty liver in obese children: prevalence and correlation with anthropometric measurements and hyperlipidemia. 1588 25

In white adipose tissue (WAT), hormone-sensitive lipase (HSL) can mediate lipolysis, a central pathway in obesity and diabetes. Gene-targeted HSL-deficient (HSL-/-) mice with no detectable HSL peptide or activity (measured as cholesteryl esterase) have WAT abnormalities, including low mass, marked heterogeneity of cell diameter, increased diacylglycerol content, and low beta-adrenergic stimulation of adipocyte lipolysis. Three transgenic mouse strains preferentially expressing human HSL in WAT were bred to a HSL-/- background. One, HSL-/- N, expresses normal human HSL (41.3 +/- 9.1% of normal activity); two express a serine-to-alanine mutant (S554A) initially hypothesized to be constitutively active: HSL-/- ML, 50.3 +/- 12.3% of normal, and HSL-/- MH, 69.8 +/- 15.8% of normal. In WAT, HSL-/- N mice resembled HSL+/+ controls in WAT mass, histology, diacylglyceride content, and lipolytic response to beta-adrenergic agents. In contrast, HSL-/- ML and HSL-/- MH mice resembled nontransgenic HSL-/- mice, except that diacylglycerol content and perirenal and inguinal WAT masses approached normal in HSL-/- MH mice. Therefore, 1) WAT expression of normal human HSL markedly improves HSL-/- WAT biochemically, physiologically, and morphologically; 2) similar levels of S554A HSL have a low physiological effect despite being active in vitro; and 3) diacylglycerol accumulation is not essential for the development of the characteristic WAT pathology of HSL-/- mice.
 ...
PMID:Human hormone-sensitive lipase (HSL): expression in white fat corrects the white adipose phenotype of HSL-deficient mice. 1596 88

Fatty liver at ultrasounds, with/ without raised plasma levels of hepatic enzymes, is common in obesity. In most cases, it is the hallmark of non-alcoholic fatty liver disease (NAFLD), a potentially progressive disease associated with insulin resistance and the metabolic syndrome (MS). We tested the hypothesis that insulin resistance per se might be associated with hepatocellular necrosis. Alanine and aspartate aminotransferases (ALT and AST; no.=799) and gamma-glutamyltranspeptidase (GGT; no.=459) were analyzed in a group of treatment-seeking obese patients recruited in 12 Italian medical centers. Insulin resistance was calculated by the homeostasis model assessment method (HOMA-IR; no.=522). Median ALT and AST increased with increasing obesity class (p=0.001 and p=0.005) and exceeded normal limits in 21.0% of cases. Also HOMA-IR increased with the obesity class (p<0.0001), and was higher in subjects with elevated ALT (median, 4.93 vs 2.89; p<0.0001). A significant correlation was observed between HOMA-IR and ALT (R2=0.208; p<0.0001), as well as between HOMA-IR and AST or GGT (R2=0.112 and R2=0.080; p<0.0001). The correlation was maintained when cases with elevated enzyme levels were omitted from analysis. Diabetes and hypertriglyceridemia were the features of the MS most commonly associated with raised liver enzymes. In logistic regression, after correction for age, gender, BMI and features of the MS, HOMA-IR maintained a highly predictive value for raised ALT, AST and GGT. We conclude that in obesity insulin resistance is a risk factor for raised liver enzyme levels, possibly related to NAFLD.
 ...
PMID:Aminotransferase and gamma-glutamyltranspeptidase levels in obesity are associated with insulin resistance and the metabolic syndrome. 1596 6

The combined effect of Peroxisome proliferator-activated receptor gamma (PPARG) Pro/Ala and interleukin-6 G174C gene variants, was evaluated in 429 Caucasian subjects in order to determine whether subjects carrying both variants were at different risk for obesity. In particular, the combined contribution of these two variants (both independent and interaction effects) to the total variation of obesity-related factors was estimated. All subjects were genotyped for codon 12 Pro/Ala locus variability and for the interleukin-6-174 C/G promoter polymorphism. Subjects with the Ala variant had significantly lower BMI, insulin resistance, triglyceride levels than those without. Furthermore, subjects with Ala variant had significantly lower IL-6 levels (0.88 +/- 0.9 vs 1.61 +/- 2.25 pg/ml; p = 0.041). In contrast, the IL6-C variant was significantly associated with lower plasma IL-6 and with lower total cholesterol levels but was not significantly associated with any other obesity risk factors. Indeed, subjects carrying both PPARG and IL-6 gene variants, had a clearly more favourable profile of obesity related risk factors than subjects with one variant, having Ala+/C+ carriers lower BMI (22.8 +/- 2.3 vs 24.14 +/- 1.9; f = 5.31; p < 0.005), insulin resistance (1.49 +/- 0.70 vs 2.13 +/- 0.92; f = 4.342; p = 0.038) and triglyceride levels (79.15 +/- 32.9 vs 98 +/- 6.73 mg/dl; f = 3.120; p < 0.005). These findings suggest that the effect of the two genetic variants on 'obesity related' factors is additive.
 ...
PMID:Role of interaction between variants in the PPARG and interleukin-6 genes on obesity related metabolic risk factors. 1602 43

Otsuka Long-Evans Tokushima fatty (OLETF) rats lack the CCK-1 receptor, are hyperphagic, progressively become obese, and develop type-2 diabetes. We recently demonstrated an increased preference for both real and sham feeding of sucrose in this strain, suggesting altered orosensory sensitivity. To investigate taste functions, we used an automated gustometer with 10-s access to different concentrations of various sapid stimuli. Tests were repeated at 10 and 18 wk of age to assess the early and advanced stages of prediabetes, respectively. Compared with age-matched, nonmutant controls, the OLETF rats showed higher avidity for sucrose at both ages. This difference increased as a function of age and tastant concentration. An exaggerated response also occurred for saccharin, alanine, and fructose, but not for Polycose. Similarly, OLETF rats consumed monosodium-glutamate more at the lower concentrations compared with controls, an effect that age also accentuated. In contrast, there was no statistical strain or age differences in responses to NaCl, MgCl2, citric acid, quinine-HCl, and the trigeminal stimulus capsaicin. These findings demonstrate that compared with controls, OLETF rats differ in their gustatory functions with an overall augmented sensitivity for sweet that progresses during prediabetes. This effect explains their overconsumption of sweet solutions and may contribute to the overall hyperphagia and obesity in this strain.
 ...
PMID:Altered taste sensitivity in obese, prediabetic OLETF rats lacking CCK-1 receptors. 1608 77


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