Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The stress system coordinates the adaptive response of the organism to real or perceived stressors. The main components of the stress system are the corticotropin-releasing hormone (CRH) and locus ceruleus-norepinephrine/ autonomic (LC/NE) systems and their peripheral effectors, the hypothalamic-pituitary-adrenal (HPA) axis, and the limbs of the autonomic system. Activation of the stress system leads to behavioral and peripheral changes that improve the ability of the organism to adjust homeostasis and increase its chances for survival. Thus, CRH and the LC/NE system stimulate arousal and attention, as well as the mesocorticolimbic dopaminergic system, which is involved in anticipatory and reward phenomena, and the amygdala, which are responsible for the generation of fear. Hypothalamic CRH plays an important role in inhibiting gonadotropin-releasing hormone secretion during stress, while via somatostatin it also inhibits growth hormone, thyrotropin-releasing hormone and thyrotropin secretion, suppressing thus reproduction, growth and thyroid function. Glucocorticoids directly inhibit pituitary gonadotropin, growth hormone and thyrotropin secretion and make the target tissues of sex steroids and growth factors resistant to these substances. In addition, glucocorticoids stimulate hepatic gluconeogenesis, and inhibit or potentiate insulin actions on skeletal muscle and adipose tissue respectively, ultimately promoting visceral adiposity and the metabolic syndrome. Glucocorticoids also have direct effects on the bone, inhibiting osteoblastic activity and causing osteoporosis. Obese subjects with psychiatric manifestations ranging from those of melancholic depression to anxiety with perception of 'uncontrollable' stress, frequently have mild hypercortisolism, while carefully screened obese subjects with no such manifestations are eucortisolemic. The former may have stress-induced glucocorticoid-mediated visceral obesity and metabolic syndrome manifestations, which in the extreme may be called a pseudo-Cushing state that needs to be differentiated from frank Cushing syndrome. Stress-induced hypercortisolism and visceral obesity and their cardiovascular and other sequelae increase the all-cause mortality risk of affected subjects by 2-3-fold and curtail their life expectancy by several years.
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PMID:The role of stress and the hypothalamic-pituitary-adrenal axis in the pathogenesis of the metabolic syndrome: neuro-endocrine and target tissue-related causes. 1099 9

Sex hormone-binding globulin (SHBG) is a plasma glycoprotein with high binding affinity for testosterone and dihydrotestosterone and lower affinity for estradiol. SHBG is synthesized in the liver, and its plasma level is important in the regulation of plasma free and albumin-bound androgens and estrogens. Obesity and particularly excess visceral fat, known risk factors for cardiovascular and metabolic diseases, are associated with decreased testosterone levels in males and SHBG levels in both sexes. SHBG is usually positively correlated with high-density lipoprotein cholesterol and negatively correlated with triglyceride and insulin concentrations. A positive association between SHBG and various measures of insulin sensitivity has been demonstrated in both sexes, suggesting that decreased SHBG levels may be one of the components of the metabolic syndrome. We have examined pituitary-adrenocortical function, glucose tolerance, and lipoprotein and hormone levels in a large cohort of Finnish males. Abdominal obesity appears to be associated with slight hypocortisolemia and increased sensitivity to exogenous adrenocorticotropin stimulation, which may contribute to the hyperinsulinemia and related metabolic changes including decreased SHBG levels in males.
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PMID:Synthesis and regulation of sex hormone-binding globulin in obesity. 1099 12

Overproduction of corticotropin-releasing hormone (CRH) and stress system abnormalities are seen in psychiatric diseases such as depression, anxiety, eating disorders, and addiction. Investigations of CRH type 1 receptor (CRHR1) nonpeptide antagonists suggest therapeutic potential for treatment of these and other neuropsychiatric diseases. However, overproduction of CRH in the brain and on its periphery and disruption of the hypothalamic-pituitary-adrenal axis are also found in 'somatic' disorders. Some rare forms of Cushing's disease and related pituitary/adrenal disorders are obvious applications for CRHR1 antagonists. In addition, however, these antagonists may also be effective in treating more common somatic diseases. Patients with obesity and metabolic syndrome who often have subtle, but chronic hypothalamic-pituitary-adrenal hyperactivity, which may reflect central dysregulation of CRH and consequently glucocorticoid hypersecretion, could possibly be treated by administration of CRHR1 antagonists. Hormonal, autonomic, and immune aberrations are also present in chronic inflammatory, autoimmune, and allergic diseases, with considerable evidence linking CRH with the observed abnormalities. Furthermore, autonomic dysregulation is a prominent feature of common gastrointestinal disorders, such as irritable bowel syndrome and peptic ulcer disease. Patients with irritable bowel syndrome and other gastrointestinal disorders frequently develop altered pain perception and affective symptoms. CRH acts peripherally to modulate bowel activity both directly through the autonomic system and centrally by processing viscerosensory and visceromotor neural signals. This review presents clinical and preclinical evidence for the role of CRH in the pathophysiology of these disorders and for potential diagnostic and therapeutic applications of CRHR1 antagonists. Recognition of a dysfunctional stress system in these and other diseases will alter the understanding and treatment of 'psychosomatic' disorders.
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PMID:Nonpeptide corticotropin-releasing hormone receptor type 1 antagonists and their applications in psychosomatic disorders. 1552 86

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders resulting from deficiency of one of the five enzymes required for synthesis of cortisol in the adrenal cortex. The most common form of the disease is classic 21-hydroxylase deficiency, which is characterized by decreased synthesis of glucocorticoids and often mineralocorticoids, adrenal hyperandrogenism and impaired development and function of the adrenal medulla. The clinical management of classic 21-hydroxylase deficiency is often suboptimal, and patients are at risk of developing in tandem iatrogenic hypercortisolism and/or hyperandogenism. Limitations of current medical therapy include the inability to control hyperandrogenism without employing supraphysiologic doses of glucocorticoid, hyperresponsiveness of the hypertrophied adrenal glands to adrenocorticotropic hormone (ACTH) and difficulty in suppressing ACTH secretion from the anterior pituitary. Puberty imposes increased difficulty in attaining adrenocortical suppression despite optimal substitution therapy and adherence to medical treatment. Alterations in the endocrine milieu at puberty may influence cortisol pharmacokinetics and, consequently, the handling of hydrocortisone used as replacement therapy. Recent studies have demonstrated a significant increase in cortisol clearance at puberty and a shorter half-life of free cortisol in pubertal females compared with males. Furthermore, children with classic CAH have elevated fasting serum insulin concentrations and insulin resistance. The latter may further enhance adrenal and/or ovarian androgen secretion, decrease the therapeutic efficacy of glucocorticoids and contribute to later development of the metabolic syndrome and its complications.
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PMID:Classic congenital adrenal hyperplasia and puberty. 1555 90

The metabolic syndrome has several similarities with Cushing's syndrome (impaired glucose tolerance, hypertension, dyslipidemia, central obesity) suggesting that abnormalities in the regulation of the hypothalamic-pituitary-adrenal axis may have a link with the metabolic syndrome. Several studies suggested an association between the clinical signs of the metabolic syndrome and the increased hypothalamic-pituitary-adrenal axis activity based on increased cortisol concentration at 09.00 a.m. and increased cortisol response to corticotropin. According to the Barker hypothesis the fetal malnutrition could determine adult cardiovascular diseases (coronary heart disease, hypertension), some endocrine and metabolic disorders (obesity, type 2 diabetes and hyperlipidemia). The suggested mechanism of the phenomenon is that the suboptimal fetal nutrition results in glucocorticoid overproduction. The 11beta-hydroxysteroid dehydrogenase (converts biological inactive cortisone to cortisol and vice versa) is an important enzyme in cortisol metabolism. The increased expression of 11beta-hydroxysteroid dehydrogenase type 1 in fat tissue could lead to central obesity and impaired glucose tolerance. The hypothesis that increased corticotropin-releasing hormone production drives the overactive hypothalamo-pituitary-adrenal axis was not proven. Further investigations are needed to identify additional pathogenetic factors and to find new therapeutic possibilities.
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PMID:[Correlations between the hypothalamo-pituitary-adrenal axis and the metabolic syndrome]. 1572 52

Cytokines mediate and control immune and inflammatory responses. Complex interactions exist between cytokines, inflammation and the adaptive responses in maintaining homeostasis, health, and well-being. Like the stress response, the inflammatory reaction is crucial for survival and is meant to be tailored to the stimulus and time. A full-fledged systemic inflammatory reaction results in stimulation of four major programs: the acute-phase reaction, the sickness syndrome, the pain program, and the stress response, mediated by the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Common human diseases such as atopy/allergy, autoimmunity, chronic infections and sepsis are characterized by a dysregulation of the pro- versus anti-inflammatory and T helper (Th)1 versus Th2 cytokine balance. Recent evidence also indicates the involvement of pro-inflammatory cytokines in the pathogenesis of atherosclerosis and major depression, and conditions such as visceral-type obesity, metabolic syndrome and sleep disturbances. During inflammation, the activation of the stress system, through induction of a Th2 shift, protects the organism from systemic 'overshooting' with Th1/pro-inflammatory cytokines. Under certain conditions, however, stress hormones may actually facilitate inflammation through induction of interleukin (IL)-1, IL-6, IL-8, IL-18, tumor necrosis factor-alpha and C-reactive protein production and through activation of the corticotropin-releasing hormone/substance P-histamine axis. Thus, a dysfunctional neuroendocrine-immune interface associated with abnormalities of the 'systemic anti-inflammatory feedback' and/or 'hyperactivity' of the local pro-inflammatory factors may play a role in the pathogenesis of atopic/allergic and autoimmune diseases, obesity, depression, and atherosclerosis. These abnormalities and the failure of the adaptive systems to resolve inflammation affect the well-being of the individual, including behavioral parameters, quality of life and sleep, as well as indices of metabolic and cardiovascular health. These hypotheses require further investigation, but the answers should provide critical insights into mechanisms underlying a variety of common human immune-related diseases.
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PMID:Cytokine dysregulation, inflammation and well-being. 1616 5

An increasing number of researchers of the metabolic syndrome assume that many mechanisms are involved in its complex pathophysiology such as an increased sympathetic activity, disorders of the hypothalamo-pituitary-adrenal axis, the action of chronic subclinical infections, proinflammatory cytokines, and the effect of adipocytokines or psychoemotional stress. An increasing body of scientific research in this field confirms the role of the neurotrophins and mastocytes in the pathogenesis of inflammatory and immune diseases. Recently it has been proved that neurotrophins and mastocytes have metabotrophic effects and take part in the carbohydrate and lipid metabolism. In the early stage of the metabolic syndrome we established a statistically significant increase in the plasma levels of the nerve growth factor. In the generalized stage the plasma levels of the neutrophines were statistically decreased in comparison to those in the healthy controls. We consider that the neurotrophin deficit is likely to play a significant pathogenic role in the development of the metabolic anthropometric and vascular manifestations of the generalized stage of MetSyn. We suggest a hypothesis for the etiopathogenesis of the metabolic syndrome based on the neuro-immuno-endocrine interactions. The specific pathogenic pathways of MetSyn development include: (1) increased tissue and plasma levels of proinflammatory cytokines Interleukin-1(IL-1), Interleukin-6 (IL-6 ) and tumor necrosis factor - alpha (TNF-alpha) caused by inflammatory and/or emotional distress; (2) increased plasma levels of neurotrophin - nerve growth factor (NGF) caused by the high IL-1, IL-6 and TNFalpha levels; (3) high plasma levels of NGF which enhance activation of: the autonomous nerve system--vegetodystonia (disbalance of neurotransmitters); Neuropeptide Y (NPY)--enhanced feeding, obesity and increased leptin plasma levels; hypothalamo-pituitary-adrenal axis--increased corticotropin-releasing hormone (CRH) and cortisol (hormonal disbalance); immune cells--increased number and degranulation of mastocytes (MC)--immunological disbalance; (4) as a result of 1-3 insulin resistance is exhibited leading to diabetes mellitus. The hypothesis is confirmed by results obtained after 6-month nonsteroid anti-inflammatory treatment of patients with MetSyn. These results are reported in a separate publication.
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PMID:Metabolic syndrome--neurotrophic hypothesis. 1654 15

Nutritional factors have a critical influence during prenatal life on the development and regulation of networks involved in body weight and feeding regulation. To establish the influence of the macronutrient type on feeding regulatory mechanisms and more particularly on stimulatory pathways (galanin and orexins), we fed female rats on either a high-carbohydrate (HC), a high-fat (HF), or a well-balanced control diet during gestation and lactation, and measured peptide expression in the hypothalamus and important hormones (leptin, insulin) in their pups at weaning. HF weanlings were 30% lighter than control and HC pups (P<0.001). They were characterized by reduced plasma glucose and insulin levels (P<0.01 or less). Their galanin and orexin systems were upregulated as shown by the significant augmentation of mRNA expression in the paraventricular nucleus and lateral hypothalamus, respectively. Inhibitory peptides like corticotropin-releasing hormone and neurotensin were not affected by this dietary treatment during early life. There was, therefore, a more intense drive to eat in HF pups, perhaps to compensate for the lower body weight at weaning. HF diets during early life had meanwhile some positive consequences: the lower metabolic profile might be beneficial in precluding the development of obesity and metabolic syndrome later in life. This is however valid only if the orexigenic drive is normalized after weaning.
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PMID:Hypothalamic orexigenic peptides are overexpressed in young Long-Evans rats after early life exposure to fat-rich diets. 1648 82

The immune and neuroendocrine systems are closely involved in the regulation of metabolism at peripheral and central hypothalamic levels. In both physiological (meals) and pathological (infections, traumas and tumors) conditions immune cells are activated responding with the release of cytokines and other immune mediators (afferent signals). In the hypothalamus (central integration), cytokines influence metabolism by acting on nucleus involved in feeding and homeostasis regulation leading to the acute phase response (efferent signals) aimed to maintain the body integrity. Peripheral administration of cytokines, inoculation of tumor and induction of infection alter, by means of cytokine action, the normal pattern of food intake affecting meal size and meal number suggesting that cytokines acted differentially on specific hypothalamic neurons. The effect of cytokines-related cancer anorexia is also exerted peripherally. Increase plasma concentrations of insulin and free tryptophan and decrease gastric emptying and d-xylose absorption. In addition, in obesity an increase in interleukin (IL)-1 and IL-6 occurs in mesenteric fat tissue, which together with an increase in corticosterone, is associated with hyperglycemia, dyslipidemias and insulin resistance of obesity-related metabolic syndrome. These changes in circulating nutrients and hormones are sensed by hypothalamic neurons that influence food intake and metabolism. In anorectic tumor-bearing rats, we detected upregulation of IL-1beta and IL-1 receptor mRNA levels in the hypothalamus, a negative correlation between IL-1 concentration in cerebro-spinal fluid and food intake and high levels of hypothalamic serotonin, and these differences disappeared after tumor removal. Moreover, there is an interaction between serotonin and IL-1 in the development of cancer anorexia as well as an increase in hypothalamic dopamine and serotonin production. Immunohistochemical studies have shown a decrease in neuropeptide Y (NPY) and dopamine (DA) and an increase in serotonin concentration in tumor-bearing rats, in first- and second-order hypothalamic nuclei, while tumor resection reverted these changes and normalized food intake, suggesting negative regulation of NPY and DA systems by cytokines during anorexia, probably mediated by serotonin that appears to play a pivotal role in the regulation of food intake in cancer. Among the different forms of therapy, nutritional manipulation of diet in tumor-bearing state has been investigated. Supplementation of tumor bearing rats with omega-3 fatty acid vs. control diet delayed the appearance of tumor, reduced tumor-growth rate and volume, negated onset of anorexia, increased body weight, decreased cytokines production and increased expression of NPY and decreased alpha-melanocyte-stimulating hormone (alpha-MSH) in hypothalamic nuclei. These data suggest that omega-3 fatty acid suppressed pro-inflammatory cytokines production and improved food intake by normalizing hypothalamic food intake-related peptides and point to the possibility of a therapeutic use of these fatty acids. The sum of these data support the concept that immune cell-derived cytokines are closely related with the regulation of metabolism and have both central and peripheral actions, inducing anorexia via hypothalamic anorectic factors, including serotonin and dopamine, and inhibiting NPY leading to a reduction in food intake and body weight, emphasizing the interconnection of the immune and neuroendocrine systems in regulating metabolism during infectious process, cachexia and obesity.
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PMID:Hypothalamic integration of immune function and metabolism. 1687 87

Non-glucocorticoid inhibitors of the HPA-system are of utmost interest in the treatment of diseases with impaired regulation of this system, like the metabolic syndrome and depression. In rats, a fragment of the thyreotropin-releasing hormone (TRH) preprohormone, preproTRH((178-199)), has been demonstrated to inhibit basal and stimulated secretion of cortisol. Our pilot study aimed to explore the first time similar effects of the homologue peptide preproTRH((158-183)) in healthy humans. In a double-blind within-subject comparison, eight healthy young men were infused intravenously with placebo and preproTRH((158-183)) at varying doses of 5, 10, 25 and 50 mg/kg of body weight. After 15 min of infusion a corticotropin-releasing hormone (CRH)/vasopressin-test was performed. Plasma concentrations of pituitary hormones and free thyroxine, blood pressure, heart rate and feelings of activation and mood were assessed repeatedly at close intervals. Individual hormone profiles and collapsed data across all doses did not reveal any effects of preproTRH((158-183)) on HPA-activity, although it increased TSH and fT4, stimulated the release of GH and increased systolic blood pressure in the course of the experiment (p<0.05, for all effects). Self-reports indicated enhanced feelings of activation and general well-being following preproTRH (p<0.05). Our data exclude a substantial inhibitory effect of preproTRH((158-183)) on HPA secretory activity and, thus, contrast with findings in rats. In humans, the peptide appears to even exert an albeit weak stimulatory effect on autonomic stress systems as indicated by increased cardiovascular activity in combination with enhanced subjective arousal.
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PMID:PreproTRH(158-183) fails to affect pituitary-adrenal response to CRH/vasopressin in man: a pilot study. 1748 75


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