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 1988, insulin-like growth factor-binding protein-1 (IGFBP-1) became the first characterized member of a group of structurally related soluble proteins which specifically bind and modulate the actions of the IGFs. Since then, a wealth of information has accumulated regarding the physiology of this dynamic serum protein. In this review, we update our 1993 summary (Lee PDK et al. Proc Soc Exp Biol Med 204:4-29) of the status of IGFBP-1 research. The IGFBP-1 protein sequence contains 12 N-terminal and 6 C-terminal cysteine residues which are conserved in other mammalian IGFBP-1 sequences and amongst other IGFBPs; both of the cysteine-rich regions are required for optimal IGF binding. The nonconserved IGFBP-1 midregion may act as both a hinge which defines ligand binding characteristics and as a specific target for protease activity. Integrin-binding and phosphorylation sites within the IGFBP-1 sequence have functional significance in vitro, but their physiologic relevance in vivo have not been defined. The human IGFBP-1 and IGFBP-3 genes are contiguous and located in close proximity to the homeobox A (HOXA) gene cluster on chromosome 7. The other IGFBP genes, located on chromosomes 2, 12, and 17, are also associated with HOX clusters, suggesting evolutionary linkage of the IGFBP and HOX gene families. Similarities between the hIGFBP-1 and phosphoenolpyruvate kinase (PEPCK) promoters, including regions conferring insulin, glucocorticoid, and cyclic adenosine-monophosphate responses, are consistent with our previous hypothesis that IGFBP-1 is involved in regulation of glucose metabolism. The tissue-specific patterns of IGFBP-1 gene expression in liver, kidney, decidua, and ovary may be due to stimulation of IGFBP-1 transcription by hepatic nuclear factor 1 (HNF1) proteins. Clinical and basic studies of IGFBP-1 physiology have been aided by several recently developed assay methods. Numerous investigations have confirmed that insulin, via inhibition of IGFBP-1 transcription, is the primary determinant of IGFBP-1 expression both in vitro and in vivo. IGF-I and IGF-II also have specific inhibitory effects on IGFBP-1 expression. Glucocorticoids and cAMP stimulate IGFBP-1 transcription, but these effects are observed only in conditions of low or absent insulin effect. Other stimulants of IGFBP-1 expression include thyroid hormones and epidermal growth factor. Phorbol ester stimulation of IGFBP-1 expression can supersede the effects of insulin in vitro;however, the mechanism and in vivo correlates of this effect have not been determined. Cytokines and, perhaps, growth hormones may affect IGFBP-1 expression, perhaps by altering the regulatory actions of insulin; this effect may have important clinical relevance. IGFBP-1 expression is upregulated in liver and (nonhuman) kidney during postinjury regeneration. The IGF-inhibitory actions of IGFBP-1 has been confirmed by numerous in vitro studies and several in vivo animal investigations, including administration of recombinant IGFBP-1 and IGFBP-1 transgenic models. IGFBP-1 has been shown to inhibit somatic linear growth, weight gain, tissue growth, and glucose metabolism. Moreover, IGFBP-1 appears to be a primary determinant of free IGF-I levels in serum. Excess levels of IGFBP-1 may contribute to growth failure in intrauterine growth restriction and in pediatric chronic renal failure, while low IGFBP-1 levels are associated with obesity and with cardiovascular risk factors in insulin resistance syndromes. Serum IGFBP-1 measurements may be useful biochemical marker in these pathologic conditions. IGFBP-1 is expressed in decidualized stromal cells of the uterine endometrium and in ovarian granulosa cells. IGFBP-1, together with IGFs, insulin, ovarian steroids, cytokines, and other factors, is involved in a complex system which regulates menstrual cycles, ovulation, decidualization, blastocyst implantation, and fetal growth. (ABSTRACT TRUNCATED)
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PMID:Insulin-like growth factor binding protein-1: recent findings and new directions. 940 39

To evaluate the metabolic effects of long-term treatment with recombinant human (rh) GH in short children with chronic renal failure (CRF), annual oral glucose tolerance tests (oGTT) during rhGH therapy for up to 5 y in 53 prepubertal children with CRF on conservative treatment, dialysis, and after renal transplantation were compared with that of 12 age-matched children treated with rhGH for idiopathic short stature. At the start of rhGH treatment, fasting values of glucose, insulin, glycosylated Hb A (HbA1C), triglycerides, cholesterol, glucose, and insulin responses during oGTT were significantly elevated in all patient groups compared with control subjects (p < 0.001). In the total population, fasting and 2-h postprandial glucose concentrations were inversely correlated with GFR and positively with age and methylprednisolone dosage in transplanted patients. Fasting insulin levels were positively correlated with body mass index and inversely with GFR. RhGH treatment was not associated with a change in fasting or stimulated glucose concentrations in any treatment group throughout the observation period. In contrast, serum insulin levels increased during the first treatment year in all groups, resulting in a more marked elevation of integrated insulin levels in transplant (1402 +/- 179 pM) and dialysis (1025 +/- 114 pM) patients compared with conservatively treated patients (829 +/- 94 pM), and control subjects (719 +/- 89 pM) (p < 0.01). Hyperinsulinemia persisted in all treatment groups for up to 5 y of follow-up. In conclusion, age, renal function, and obesity are the major independent predictors of glucose tolerance in children with CRF. Long-term rhGH treatment does not affect glucose tolerance, but aggravates the preexisting hyperinsulinemia in children with end-stage renal disease. In concert with the dyslipidemia of uremia, the rhGH-promoted hyperinsulinemia may contribute to the long-term risk for premature atherosclerosis in patients with childhood onset CRF.
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PMID:Metabolic effects of long-term growth hormone treatment in prepubertal children with chronic renal failure and after kidney transplantation. The German Study Group for Growth Hormone Treatment in Chronic Renal Failure. 947 86

1. Obesity is the most common nutritional disorder in the US and is a major cause of human essential hypertension. Although the precise mechanisms by which obesity raises blood pressure (BP) are not fully understood, there is clear evidence that abnormal kidney function plays a key role in obesity hypertension. 2. Obesity increases tubular reabsorption and this shifts pressure natriuresis towards higher BP. The increased tubular reabsorption is not directly related to hyperinsulinaemia, but is closely linked to activation of the sympathetic and renin-angiotensin systems, and possible changes in intrarenal physical forces caused by medullary compression due to accumulation of adipose tissue around the kidney and increased extracellular matrix within the kidney. 3. Obesity is also associated with marked renal vasodilation and increased glomerular filtration rate, which are compensatory responses that help overcome the increased tubular reabsorption and maintain sodium balance. However, chronic renal vasodilation causes increased hydrostatic pressure and wall stress in the glomeruli which, along with increased lipids and glucose intolerance, may cause glomerulosclerosis and loss of nephron function in obese subjects. Because obesity is a primary cause of essential hypertension as well as type II diabetes, there is good reason to believe that obesity may also be the most frequent cause of end-stage renal disease. 4. Future research is needed to determine the mechanisms by which excess weight gain activates the neurohumoral systems and alters renal structure and function. Because of the high prevalence of obesity in most industrialized countries, unravelling these mechanisms will likely provide a better understanding of the pathophysiology of human essential hypertension and chronic renal failure.
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PMID:Abnormal kidney function as a cause and a consequence of obesity hypertension. 949 61

This review emphasizes four major areas of pediatric hypertension. Because hypertension is the most common reason student athletes fail the sports pre-participation examinations, we have attempted to provide a rationale approach to the decision process to permit a hypertensive child to partake in leisure and competitive sports. Without question, obesity is a major reason for referral for hypertension to a pediatric nephrologist. The work-up should be directed to diet control and an exercise program to achieve sustained weight reduction. Hypertension associated with chronic renal failure and renal disease secondary to insulin-dependent diabetes mellitus is a major problem in pediatric and adult nephrology. With adequate control of systemic blood pressure, progressive decline in renal function may be delayed. By understanding these common areas of associated pediatric hypertension, a more systematic approach to the evaluation and treatment can be achieved.
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PMID:Special topics in pediatric hypertension. 961 70

Acute unilateral or bilateral rupture of the patellar tendon was diagnosed in 5 aged obese female Pere David's deer housed at a zoological park. Rupture occurred after an episode of sudden exertion in 4 of 5 deer. Fragmentation, degeneration, necrosis, and mineralization of ruptured patellar tendon fibers were found on histologic examination. Similar changes were often seen in intact contralateral tendons that did not have gross lesions. Patellar tendon rupture in humans is associated with concurrent systemic disease, such as systemic lupus erythematosus, rheumatoid arthritis, or chronic renal failure. Without evidence of underlying systemic disease, spontaneous patellar tendon rupture in deer can be considered a sequela to age-related tendinous degeneration compounded by sudden exertion and chronic overload attributable to obesity.
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PMID:Patellar tendon rupture in five deer. 962 88

Diseases in other organs may impair the male reproductive system. Acute critical conditions such as severe trauma, surgery, myocardial infarction, burns, liver failure, intoxication, or starvation are associated with suppression of gonadotropin secretion and secondary hypogonadism. With chronic illnesses, a primary testicular disorder with elevated gonadotropin levels may occur. This may be associated with increased peripheral conversion of androgens to estrogens, resulting in clinical presentation of combined androgen deficiency and estrogen excess. The association of hypogonadism and feminization with cirrhosis of the liver is a classic example. Types of hypogonadism that may occur with chronic anemia, chronic renal failure, chronic spinal cord injury, thyroid diseases, Cushing's syndrome, diabetes mellitus, obesity, HIV infection, neoplasia, and other chronic illnesses are also described. Numerous drugs have side effects on the reproductive system.
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PMID:Reproductive effects of nontesticular illness. 992 10

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder. Specific diagnostic criteria for BBS have now been defined. At least four of the five cardinal signs of mental retardation, obesity, hypogenitalism in men, distal limb anomalies, and progressive tapetoretinal degeneration of the retina are required for the diagnosis. Renal involvement has been described as a sixth cardinal feature. Chronic renal failure occurs in 30%-60% of patients. Hypertension has been noted in 50%-66% of cases. Renal abnormalities reflect a defect in maturation of the kidneys. We present a patient with BBS who had bilateral microaneurysms and occlusions in renal arterioles.
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PMID:Renal vascular abnormalities in Bardet-Biedl syndrome. 1060 22

Patients with chronic renal failure (CRF) are at increased risk for pathological calcifications because of increased serum calcium-phosphorus products. A minority, including those undergoing dialysis, develop a syndrome of deep skin ulcerations in association with calcification of subcutaneous arterioles. The body distribution of the skin lesions may be proximal (central), distal (peripheral), or both. Since 1968, this syndrome has been called "calciphylaxis" in the belief that it is the human analogue of Selye's experimental models of tissue calcification. Our review emphasizes that this syndrome comprises two separate processes not found in calciphylaxis: calcification of subcutaneous arterioles and infarctions of subcutaneous adipose tissue (panniculus adiposus) and skin. The infarctions are acute and clinically dramatic, whereas the calcific arteriolopathy is preexistent, having developed slowly, sometimes over years, and silently. Separating these two processes facilitates analyses of pathogenetic factors, such as those that target subcutaneous arterioles for calcification and those that interfere with blood flow through the calcified arterioles, sufficient in some patients to cause the infarctions, and of why obesity in CRF is a syndrome risk factor. This approach further helps to provide a much needed standardized definition of the syndrome, thereby facilitating comparisons of the results of such treatments as parathyroidectomy, anticoagulants, and phosphate binders. Finally, the separation shows why the application of such terms as calciphylaxis and calcifying panniculitis to this syndrome is inappropriate.
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PMID:Calcified subcutaneous arterioles with infarcts of the subcutis and skin ("calciphylaxis") in chronic renal failure. 1073 77

There is increasing evidence that androgen therapy in men may be effectively applied in several conditions to improve well being and health. Classical indications for androgen therapy in males are represented by primary or secondary hypogonadism, delayed puberty, aplastic anemia and that secondary to chronic renal failure, protein wasting diseases such as trauma, burns, tumors and infectious diseases. Androgen innovating applications in men are represented by aging and visceral obesity associated with the metabolic syndrome. In addition, it is clear that appropriate testosterone treatment can be adequately used in male contraception, provided spermatogenesis is abolished and tolerability is adequate. Due to unphysiological hormone levels achieved by currently available testosterone preparations, new delivery systems have been produced to achieve more physiological and sustained hormone levels and improve tolerability and action at the levels of target tissues. Some of them are now available in several countries and new formulas are under development.
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PMID:Testosterone therapy in men: clinical and pharmacological perspectives. 1080 80

The melanocortin (ACTH/MSH) peptides exert a number of central effects. In the eighties, we described for the first time a role for melanocortins in the central control of appetite. We showed that the injection of ACTH-(1-24) into a brain lateral ventricle reduced food intake up to 76.6% in starved rats. Injections into the ventromedial hypothalamus during the nocturnal feeding phase also markedly inhibited food intake. These effects were also confirmed in mice and rabbits. Targeted disruption of the MC4 receptor resulting in obesity in mice explained the role of this receptor in mediating effects of melanocortins on food intake. Administration of MC4 receptor agonists leads to acute reduction in food intake and body weight, while the reverse effects are observed after administration of selective MC4 receptor antagonists, confirming the role of the melanocortins in mediating a tonic inhibition on feeding behavior. Moreover, immobilization stress-induced anorexia may be partially reversed by single and repeated intracerebroventricular administration of selective MC4 receptor antagonists. It is thus evident that MC4 receptor blockage can reduce stress-induced anorexia and that repeated injections of selective MC4 receptor antagonists have a sustained effect on food intake without any sign of tachyphylaxis. However, we have also shown that the behavioral effects of CRF (anorexia and grooming) are not influenced by MC4 receptor blockage. These effects of CRF are thus not due to an indirect mechanism caused by an increased release of melanocortins acting on the central MC receptors.
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PMID:Melanocortins and feeding behavior. 1084 May 89


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