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

In obesity, adipocytes undergo dramatic morphological and molecular changes associated with alterations in their gene expression profile. To identify genes differentially modulated in white adipose tissue (WAT) of obese db/db mice compared to wild type (wt) mice, we utilized RNA fingerprinting. Among the 52 candidates that we identified, we focused here on cathepsin K (ctsk), a cysteine protease, prevalently localized in lysosomes and involved in bone extracellular matrix degradation. In db/db mice, WAT ctsk mRNA was elevated 5.9-fold, as were Mitf and TFE3 (2- and 3.3-fold respectively), two transcription factors involved in ctsk induction in osteoclasts. Moreover, the level of WAT ctsk mRNA was increased in other obese models including A(y), fat, and tubby (2.8-, 3.2-, and 4.9-fold respectively) and decreased in mice undergoing weight loss. Despite the ubiquitous distribution of the ctsk transcript, we demonstrated that the obesity related increase is specific to the adipocytes. Further, in vitro experiments proved that the abundance of ctsk transcript increases upon adipose conversion of the established cell line of preadipocytes 3T3-F442A. In addition, ctsk gene expression was examined in adipose tissue of 21 lean and obese male subjects and significant correlations with BMI (r = 0.54, P = 0.012) and plasma leptin levels (r = 0.54, P = 0.015) were found. In conclusion, the WAT of obese db/db mice exhibits a different expression profile from that of the wt mice, and cathepsin K can be considered a novel marker of obesity and a target for the inhibition of adipose mass growth.
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PMID:Identification of cathepsin K as a novel marker of adiposity in white adipose tissue. 1265 57

The molecular mechanisms by which obesity increases the risk of cardiovascular diseases are poorly understood. The purpose of this study was to identify candidate biomarkers overexpressed in adipose tissue of obese subjects that could link expanded fat mass to atherosclerosis. We compared gene expression profile in subcutaneous adipose tissue (scWAT) of 28 obese and 11 lean subjects using microarray technology. This analysis identified 240 genes significantly overexpressed in scWAT of obese subjects. The genes were then ranked according to the correlation between gene expression and body mass index (BMI). In this list, the elastolytic cysteine protease cathepsin S was among the highly correlated genes. RT-PCR and Western blotting confirmed the increase in cathepsin S mRNA (P=0.006) and protein (P<0.05) in obese scWAT. The circulating concentrations of cathepsin S were also significantly higher in obese than in nonobese subjects (P<0.0001). Both cathepsin S mRNA in scWAT and circulating levels were positively correlated with BMI, body fat, and plasma triglyceride levels. In addition, we show that the proinflammatory factors, lipopolysaccharide, interleukin-1beta, and tumor necrosis factor-alpha increase cathepsin S secretion in human scWAT explants. This study identifies cathepsin S as a novel marker of adiposity. Since this enzyme has been implicated in the development of atherosclerotic lesions, we propose that cathepsin S represents a molecular link between obesity and atherosclerosis.
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PMID:Cathepsin S, a novel biomarker of adiposity: relevance to atherogenesis. 1598 26

We previously showed that the cysteine protease cathepsin S (CTSS), known to degrade several components of the extracellular matrix (ECM), is produced by human adipose cells and increased in obesity. Because ECM remodeling is a key process associated with adipogenesis, this prompted us to assess the potential role of CTSS to promote preadipocyte differentiation. Kinetic studies in primary human preadipocytes revealed a modest increase in CTSS gene expression and secretion at the end of differentiation. CTSS activity was maximal in preadipocyte culture medium but decreased thereafter, fitting with increased release of the CTSS endogenous inhibitor, cystatin C, during differentiation. Inhibition of CTSS activity by an exogenous-specific inhibitor added along the differentiation, resulted in a 2-fold reduction of lipid content and expression of adipocyte markers in differentiated cells. Conversely, the treatment of preadipocytes with human recombinant CTSS increased adipogenesis. Moreover, CTSS supplementation in preadipocyte media markedly reduced the fibronectin network, a key preadipocyte-ECM component, the decrease of which is required for adipogenesis. Using immunohistochemistry on serial sections of adipose tissue of obese subjects, we showed that adipose cells staining positive for CTSS are mainly located in the vicinity of fibrosis regions containing fibronectin. Herein we propose that CTSS may promote human adipogenesis, at least in part, by degrading fibronectin in the early steps of differentiation. Taken together, these results indicate that CTSS released locally by preadipocytes promotes adipogenesis, suggesting a possible contribution of this protease to fat mass expansion in obesity.
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PMID:Cathepsin s promotes human preadipocyte differentiation: possible involvement of fibronectin degradation. 1682 21

The first type 2 diabetes (T2D) gene to be identified in a genome wide scan followed by positional cloning was CAPN10 encoding the cysteine protease calpain-10. Subsequently, a large number of studies have investigated variation in CAPN10 in relation to T2D. Two CAPN10 single nucleotide polymorphisms (SNPs), the SNP43 (rs3792267) and the SNP44 (rs2975760), have been associated with T2D in some, but not all studies conducted in a wide range of ethnicities. We investigated the two SNPs for association with T2D in a relatively large, homogenous population of Danish whites (n = 1359 T2D cases, n = 4659 normoglycemic and glucose-tolerant control subjects), however, no significant associations of the SNP43 or the SNP44 variant with T2D were found. Neither were the two variants associated with obesity, and no association of either variant with diabetes-related quantitative traits was found in a study involving a population-based sample of 5698 middle-aged subjects. Meta-analyses, however, of the present and previously published studies involving 15,368 (SNP43) or 13,628 (SNP44) subjects yielded odds ratios of 1.09 (95% CI 1.02-1.16, p = 0.007) and 1.15 (1.07-1.23, p = 0.0002), respectively, for association with T2D. In conclusion, in a relatively large study sample of whites we found no consistent evidence of association of the CAPN10 SNP43 or SNP44 with T2D, obesity, or related quantitative traits, although meta-analyses of these two CAPN10 SNPs demonstrated an association with T2D.
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PMID:Variation in CAPN10 in relation to type 2 diabetes, obesity and quantitative metabolic traits: studies in 6018 whites. 1685 2

Type 2 diabetes mellitus (T2DM) can lead to death without treatment and it has been predicted that the condition will affect 215 million people worldwide by 2010. T2DM is a multifactorial disorder whose precise genetic causes and biochemical defects have not been fully elucidated, but at both levels, calpains appear to play a role. Positional cloning studies mapped T2DM susceptibility to CAPN10, the gene encoding the intracellular cysteine protease, calpain 10. Further studies have shown a number of noncoding polymorphisms in CAPN10 to be functionally associated with T2DM while the identification of coding polymorphisms, suggested that mutant calpain 10 proteins may also contribute to the disease. Here we review recent studies, which in addition to the latter enzyme, have linked calpain 5, calpain 3, and its splice variants, calpain 2 and calpain 1 to T2DM-related metabolic pathways along with T2DM-associated phenotypes, such as obesity and impaired insulin secretion, and T2DM-related complications, such as epithelial dysfunction and diabetic cataract.
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PMID:Calpains and their multiple roles in diabetes mellitus. 1715 22

Several autoimmune diseases are thought to be mediated in part by interleukin (IL)-18. Many are those with associated increased interferon-gamma (IFNgamma) levels such as systemic lupus erythematosus, macrophage activation syndrome, rheumatoid arthritis, Crohn's disease, psoriasis, and graft-versus-host disease. In addition, ischemia, including acute renal failure in human beings, appears to involve IL-18. Animal studies also support the concept that IL-18 is a key player in models of lupus erythematosus, atherosclerosis, graft-versus-host disease, and hepatitis. Unexpectedly, IL-18 plays a role in appetite control and the development of obesity. IL-18 is a member of the IL-1 family; IL-1beta and IL-18 are related closely, and both require the intracellular cysteine protease caspase-1 for biological activity. The IL-18 binding protein, a naturally occurring and specific inhibitor of IL-18, neutralizes IL-18 activities and has been shown to be safe in patients. Other options for reducing IL-18 activities are inhibitors of caspase-1, human monoclonal antibodies to IL-18, soluble IL-18 receptors, and anti-IL-18 receptor monoclonal antibodies.
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PMID:Interleukin-18 and the pathogenesis of inflammatory diseases. 1733 92

Obesity is thought to be a major determinant in the development of cardiovascular diseases, but the mechanisms whereby enlarged adipose tissue affects vascular function remain poorly defined. Chronic inflammation is a common feature of obesity and atherosclerosis, and several inflammatory markers produced by adipose tissue have been considered as candidates that potentially favor the development of atherosclerotic lesions in humans. To identify other effective candidates, we combined bioclinical data for individuals of increasing weight with adipose tissue gene-expression profiling. This strategy led to the discovery of cathepsin S (CTSS), for which gene expression was strongly correlated with subjects' body mass index (BMI). CTSS is an elastolytic cysteine protease that has been implicated in the development of atherosclerotic lesions in both animal models and humans. In this review, we discuss the role of CTSS in obesity and atherosclerosis, and emphasize the potential mechanisms that could link the two diseases. We also position this protease as a potential therapeutic target to reduce associated cardiovascular risks in obese patients.
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PMID:Emerging role of cathepsin S in obesity and its associated diseases. 1737 27

Growing evidences indicate that proteases are implicated in adipogenesis and in the onset of obesity. We previously reported that the cysteine protease cathepsin K (ctsk) is overexpressed in the white adipose tissue (WAT) of obese individuals. We herein characterized the WAT and the metabolic phenotype of ctsk deficient animals (ctsk-/-). When the growth rate of ctsk-/- was compared to that of the wild type animals (WT), we could establish a time window (5-8 weeks of age) within which ctsk-/-display significantly lower body weight and WAT size as compared to WT. Such a difference was not observable in older mice. Upon treatment with high fat diet (HFD) for 12 weeks ctsk-/- gained significantly less weight than WT and showed reduced brown adipose tissue, liver mass and a lower percentage of body fat. Plasma triglycerides, cholesterol and leptin were significantly lower in HFD-fed-ctsk-/- as compared to HFD-fed WT animals. Adipocyte lipolysis rates were increased in both young and HFD-fed-ctsk-/-, as compared to WT. Carnitine palmitoyl transferase-1 activity, was higher in mitochondria isolated from the WAT of HFD treated ctsk-/- as compared to WT. Together, these data indicate that ctsk ablation in mice results in reduced body fat content under conditions requiring a rapid accumulation of fat stores. This observation could be partly explained by an increased release and/or utilization of FFA and by an augmented ratio of lipolysis/lipogenesis. These results also demonstrate that under a HFD, ctsk deficiency confers a partial resistance to the development of dyslipidemia.
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PMID:Cathepsin K null mice show reduced adiposity during the rapid accumulation of fat stores. 1766 61

The cysteine protease cathepsin S (CatS) is involved in the pathogenesis of autoimmune disorders, atherosclerosis, and obesity. Therefore, it represents a promising pharmacological target for drug development. We generated ligand-based and structure-based pharmacophore models for noncovalent and covalent CatS inhibitors to perform virtual high-throughput screening of chemical databases in order to discover novel scaffolds for CatS inhibitors. An in vitro evaluation of the resulting 15 structures revealed seven CatS inhibitors with kinetic constants in the low micromolar range. These compounds can be subjected to further chemical modifications to obtain drugs for the treatment of autoimmune disorders and atherosclerosis.
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PMID:Discovery of novel cathepsin S inhibitors by pharmacophore-based virtual high-throughput screening. 1863 74

Cathepsin K is a highly potent collagenase and the predominant papain-like cysteine protease expressed in osteoclasts. Cathepsin K deficiencies in humans and mice have underlined the central role of this protease in bone resorption and, thus, have rendered the enzyme as an attractive target for anti-resorptive osteoporosis therapy. In the past decade, a lot of efforts have been made in developing highly potent, selective and orally applicable cathepsin K inhibitors. Some of these inhibitors have passed preclinical studies and are presently in clinical trials at different stages of advancement. The development of the inhibitors and preliminary results of the clinical trials revealed problems and lessons concerning the in situ specificity of the compounds and their tissue targeting. In this review, we briefly summarize the history of cathepsin K research and discuss the current development of cathepsin K inhibitors as novel anti-resorptives for the treatment of osteoporosis. We also discuss potential off-target effects of cathepsin K inhibition and alternative applications of cathepsin K inhibitors in arthritis, atherosclerosis, blood pressure regulation, obesity and cancer.
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PMID:Cathepsin K inhibitors for osteoporosis and potential off-target effects. 1938 76


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