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)

The exact mechanisms by which NO mediates its neuromodulatory effects within the central control of cardiovascular functions are still unclear. Both excitatory and inhibitory actions of NO in different regions of the brainstem have been reported, and that it could be caused by direct actions of NO on neurones and/or by NO-mediated changes in local cerebral blood flow. Microinjection studies suggest that direct modulation of neuronal activity by NO through cyclic 3'-5' guanosine monophosphate (cGMP)-dependent mechanisms predominates. In contrast, endogenous NO produces. only minor changes in local cerebral blood flow, and potentiation of NO-dependent vasodilation with an inhibitor of phosphodiesterase V (PDE5i) has no significant effect on sympathetic activity. Activation of the NO-system in the lower brain stem modulates various central and reflex-activated neuronal pathways. To a large extent, this appears to be mediated by NO-induced GABA- and glutamate-release within the ventrolateral medulla (VLM) and the nucleus of the solitary tract (NTS). In addition, NO has been shown to reduce local generation of angiotensin II (AII) in all areas. Recent studies suggest that the NO-mediated modulation of autonomic function is severely impaired in cardiovascular diseases. Possibly in conjunction with AII, which triggers and promotes superoxide radical generation, chronic oxidative stress (COS) could act as a key mediator of this process. Evidence supporting this hypothesis comes from studies on pigs that were chronically treated with organic nitrates to pharmacologically induce COS. In these animals, microinjection of superoxide dismutase into the rostral VLM (RVLM) diminished sympathetic activity by up to 70%, whereas peroxynitrite, a key mediator of NO-related oxidative stress, had excitotoxic effects. Antagonism of neuronal COS may therefore represent a novel approach to counteract neurohumoral activation in diseases such hypertension, obesity and heart failure.
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PMID:Mechanisms of action of nitric oxide in the brain stem: role of oxidative stress. 1214 34

Our group has recently demonstrated (Gesta, S., Simon, M., Rey, A., Sibrac, D., Girard, A., Lafontan, M., Valet, P., and Saulnier-Blache, J. S. (2002) J. Lipid Res. 43, 904-910) the presence, in adipocyte conditioned-medium, of a soluble lysophospholipase d-activity (LPLDact) involved in synthesis of the bioactive phospholipid lysophosphatidic acid (LPA). In the present report, LPLDact was purified from 3T3F442A adipocyte-conditioned medium and identified as the type II ecto-nucleotide pyrophosphatase phosphodiesterase, autotaxin (ATX). A unique ATX cDNA was cloned from 3T3F442A adipocytes, and its recombinant expression in COS-7 cells led to extracellular release of LPLDact. ATX mRNA expression was highly up-regulated during adipocyte differentiation of 3T3F442A-preadipocytes. This up-regulation was paralleled by the ability of newly differentiated adipocytes to release LPLDact and LPA. Differentiation-dependent up-regulation of ATX expression was also observed in a primary culture of mouse preadipocytes. Treatment of 3T3F442A-preadipocytes with concentrated conditioned medium from ATX-expressing COS-7 cells led to an increase in cell number as compared with concentrated conditioned medium from ATX non-expressing COS-7 cells. The specific effect of ATX on preadipocyte proliferation was completely suppressed by co-treatment with a LPA-hydrolyzing phospholipase, phospholipase B. Finally, ATX expression was found in mature adipocytes isolated from mouse adipose tissue and was substantially increased in genetically obese-diabetic db/db mice when compared with their lean siblings. In conclusion, the present work shows that ATX is responsible for the LPLDact released by adipocytes and exerts a paracrine control on preadipocyte growth via an LPA-dependent mechanism. Up-regulations of ATX expression with adipocyte differentiation and genetic obesity suggest a possible involvement of this released protein in the development of adipose tissue and obesity-associated pathologies.
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PMID:Autotaxin is released from adipocytes, catalyzes lysophosphatidic acid synthesis, and activates preadipocyte proliferation. Up-regulated expression with adipocyte differentiation and obesity. 1264 76

The Food & Drug Administration has recently approved, or is in the process of approving newer drugs such as the phosphodiesterase inhibitors and apomorphine to treat men's health issues including erectile dysfunction. Increasing age results in a gradual hypogonadal state in men, for which different novel delivery systems of androgens are currently offered for the symptomatic patient. As such, many men are presenting to healthcare practitioners for the first time. The age of presentation for erectile dysfunction and andropause often overlaps, typically in the fifties and beyond, therefore, it makes sense to screen for erectile dysfunction in andropause patients and vice versa. Erectile dysfunction is usually a harbinger for other illnesses, such as coronary heart disease and depression. The hypogonadal state, likewise, could be a harbinger for other ill health states in men, including obesity, depression, osteoporosis and possibly memory loss. While the newer treatments for erectile dysfunction and andropause are distinctly different and targeted at symptom relief, the presentation of the patient with erectile dysfunction or andropause offers an excellent opportunity for screening for other health states and health education strategies.
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PMID:Novel treatment options for overlapping yet distinct erectile dysfunction and andropause syndromes. 1280 83

Erectile dysfunction (ED) is a common problem in men over 40-50 years of age. Risk factors include: diabetes, lipid abnormalities, smoking, hypertension, obesity, and lack of physical activity. Oral phosphodiesterase-5 inhibitors appear effective and safe in most cardiac patients.
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PMID:Erectile dysfunction in the cardiac patient. 1516 92

1. In the present study, we conducted the first randomized, double-blind, placebo-controlled study of bofu-tsusho-san (BF), an oriental herbal medicine (24 mg/day ephedrine in Ephedrae Herba and an efficacy equivalent of 280 mg caffeine, judging from the phosphodiesterase-inhibitory effect of Glycyrrhizae Radix, Forsythiae Fructus and Schizonepetae Spica and another 14 crude drugs) in obese women with impaired glucose tolerance (IGT). 2. The aim of the present study was to determine whether BF was effective in decreasing visceral adiposity and insulin resistance. Eighty-one Japanese women (body mass index (BMI) 36.5 +/- 4.8 kg/m2) with IGT and insulin resistance (IR), who had been treated with a low-calorie diet (5016 kj/day: 1200 kcal) and an exercise regimen (1254 kj/day: 300 kcal), were randomized to receive either placebo (n=40) or BF treatment (n=41) three times a day. 3. After 24 weeks treatment, the BF group lost significantly (P <0.01) more bodyweight and abdominal visceral fat without a decrease in the adjusted resting metabolic rate (RMR), whereas the placebo group lost bodyweight (P <0.05) and had no significant change in abdominal visceral fat. The BF group had a lower fasting serum insulin level (P <0.05), a lower insulin area under the curve (P <0.05) and a lower level of the homeostasis model assessment of insulin resistance (P <0.01) compared with values before treatment. 4. We conclude that BF could be a useful herbal medicine in treating obesity with IGT.
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PMID:Efficacy of bofu-tsusho-san, an oriental herbal medicine, in obese Japanese women with impaired glucose tolerance. 1547 69

Our laboratories have developed several technologies to accelerate drug discovery process on the basis of structural chemoproteomics. They include SPS technology for the efficient determination of protein structures, SCP technology for the rapid lead generation and SDF technology for the productive lead optimization. Using these technologies, we could determine many 3D structures of target proteins bound with biologically active chemicals including the structure of phosphodiesterase 5/Viagra complex and obtain highly potent compounds in animal models of obesity, diabetes, cancer and inflammation. In this paper, we will discuss concepts and applications of structural chemoproteomics for drug discovery.
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PMID:Structural chemoproteomics and drug discovery. 1581 88

An elevated circulating level of the adipocyte-derived satiety hormone leptin is an independent risk factor for cardiovascular disease. Because thrombus formation is a major cause of acute coronary events and leptin was shown previously to facilitate ADP-induced platelet aggregation, we chose to define the signaling events involved in leptin-mediated platelet activation. Using pharmacological, biochemical, and cell biological approaches, we show that leptin-induced platelet activation required activation of a signaling cascade that included the long form of the leptin receptor, three kinases [Janus kinase 2 (JAK2), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (PKB/Akt)], the insulin receptor substrate-1 (IRS-1), and the major human platelet cAMP phosphodiesterase phosphodiesterase 3A (PDE3A). Moreover, we identify a role for an intraplatelet LEPR/JAK2/IRS-1/PI3K/PKB/PDE3A molecular complex that allows for the selective leptin-mediated activation of platelets. Our data demonstrate that leptin promotes platelet activation, provides a mechanistic basis for the prothrombotic effect of this hormone, and identifies a potentially novel therapeutic avenue to limit obesity-associated cardiovascular disease.
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PMID:Leptin-mediated activation of human platelets: involvement of a leptin receptor and phosphodiesterase 3A-containing cellular signaling complex. 1588 25

Leptin resistance leads to obesity and may affect responses to the second messenger cGMP. We tested the hypothesis that the myocardial negative metabolic response to cGMP would be enhanced in leptin-resistant animals. This hypothesis was tested in anesthetized open-chest Zucker obese (n = 16) and age-matched control rats (n = 13). Coronary blood flow (microspheres) and O2 extraction (microspectrophotometry) measurements were used to determine myocardial O2 consumption (VO2). Protein phosphorylation by cGMP protein kinase and cAMP phosphodiesterase activity were also determined. Either vehicle (saline) or 8-Br-cGMP (10(-3) M) was topically applied to the left ventricular surface. Body weight was significantly greater in the obese rats (523 +/- 17 versus 322 +/- 12 g). There were no hemodynamic differences between groups. There was no difference in VO2 between lean (52 +/- 13 mL O2/min/100 g) and obese (54 +/- 9) vehicle-treated rats. 8-Br-cGMP significantly lowered VO2 in obese (35 +/- 6) but not lean (45 +/- 7) rats. This was not related to altered protein phosphorylation by the cGMP protein kinase. Cyclic GMP inhibited cAMP phosphodiesterase activity in lean but not obese hearts. Thus, the high myocardial oxygen consumption of lean rats was not significantly affected by cGMP but was reduced in obese hearts. This appeared to be related to a reduced inhibition of cAMP phosphodiesterase activity by cGMP in the Zucker obese rat.
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PMID:Negative metabolic effects of cGMP are enhanced in obese rat hearts. 1589 79

The past decade has witnessed a dramatic increase in the prevalence of obesity. Comorbidities of obesity include type 2 diabetes mellitus, hypertension, and lipid abnormalities, all of which contribute to cardiovascular disease (CVD) and are associated with endothelial dysfunction. These abnormalities frequently cluster in individuals, and the term metabolic syndrome is now widely used to define this cluster. The syndrome is frequently (although not invariably) associated with insulin resistance and CVD. Diabetes is associated with CVD, which may be asymptomatic in some cases, particularly when associated with autonomic neuropathy. This has implications for guidelines on the evaluation of patients with erectile dysfunction (ED) and CVD. Treatment of ED in men with diabetes has been revolutionized by the introduction of phosphodiesterase 5 inhibitors. However, men with diabetes tend to respond less positively to these agents, at least as currently prescribed. This decreased responsiveness may be related to the severity of endothelial function in patients with diabetes. Additional therapeutic strategies may be needed to overcome this problem.
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PMID:Endothelial and erectile dysfunction, diabetes mellitus, and the metabolic syndrome: common pathways and treatments? 1638 60

The prevalence of both cardiovascular disease (CVD) and erectile dysfunction (ED) increases with advancing age. These conditions share the common risk factors of diabetes mellitus, hypertension, hyperlipidemia, smoking, and obesity. They also share a pathophysiologic mechanism of decreased vascular blood flow via endothelial dysfunction. There are several lines of evidence that endothelial dysfunction in men with ED can be detected well before overt manifestations of vascular damage, including atherosclerotic effects. Some evidence shows that ED can be improved not only with phosphodiesterase 5 inhibitors but also by treating the risk factors directly. This includes cessation of smoking, correction of hyperlipidemia, and amelioration of obesity through weight loss. Conversely, ED may be prevented through maintenance of lean body mass, consistency of physical activity, and smoking abstinence, similar to other risk factors for CVD.
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PMID:Relation of endothelial cell function to erectile dysfunction: implications for treatment. 1638 68


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