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)

Hypofunctioning of the pituitary-adrenal axis has been suggested as the pathophysiological basis for chronic fatigue syndrome (CFS). Blunted adrenocorticotropin (ACTH) responses but normal cortisol responses to exogenous corticotropin-releasing hormone (CRH), the main regulator of this axis, have been previously demonstrated in CFS patients, some of whom had a comorbid psychiatric disorder. We wished to re-examine CRH activation of this axis in CFS patients free from concurrent psychiatric illness. A sample of 14 patients with CDC-diagnosed CFS were compared with 14 healthy volunteers. ACTH and cortisol responses were measured following the administration of 100 microg ovine CRH. Basal ACTH and cortisol values did not differ between the two groups. The release of ACTH was significantly attenuated in the CFS group (P < 0.005), as was the release of cortisol (P < 0.05). The blunted response of ACTH to exogenous CRH stimulation may be due to an abnormality in CRH levels with a resultant alteration in pituitary CRH receptor sensitivity, or it may reflect a dysregulation of vasopressin or other factors involved in HPA regulation. A diminished output of neurotrophic ACTH, causing a reduced adrenocortical secretory reserve, inadequately compensated for by adrenoceptor upregulation, may explain the reduced cortisol production demonstrated in this study.
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PMID:Blunted adrenocorticotropin and cortisol responses to corticotropin-releasing hormone stimulation in chronic fatigue syndrome. 966 18

Because alcoholism is a multi-factorial psychiatric disorder, with both psychosocial and biochemical/genetic factors leading to its manifestation in any one individual, the presence of biochemical/genetic factors alone may not lead to the manifestation of the disorder. There are numerous difficulties associated with identification of a trait abnormality in a disorder that requires suitable socio-cultural permissiveness with distinct behavioural characteristics to manifest a disorder that may not require that predisposing trait abnormality in order to develop. Numerous studies have been performed in the past to potentially identify a biochemical or genetic trait abnormality in alcoholism, and not all of them have addressed significant methodological flaws in this type of research. This review addresses some of the difficulties inherent in this research, and aims for a comprehensive review of the highlights of the search for a clinically useful trait abnormality. Some series of investigations hold promise that a trait marker for a particular subset of alcoholics may be developed, e.g. severe alcoholism and the dopamine D2 receptor gene; the level of reaction to alcoholism in family history-positive alcoholics; beta-endorphin abnormalities in specific family groups of alcoholics; reduced P3 wave event-related potentials as markers and predictors of development of substance abuse in predisposed youths; reduced growth hormone response to apomorphine as a predictor of relapse to alcoholism in early abstinence; abnormal adenylyl cyclase activity in certain defined subgroups of alcoholics; and abnormal platelet monoamine oxidase levels in subjects with a behavioural predisposition to addictive disorders. The review concludes that while there has not yet been an identification of a comprehensive trait marker for alcoholism, there is hope for identification subgroups of alcoholics with consistent biological markers within that subgroup that may well prove fruitful over time. It will then be up to a future generation of clinicians to take that information and develop prevention programmes that can incorporate this information to help the predisposed individual avoid alcohol problems.
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PMID:Trait markers for alcoholism: clinical utility. 1052 6

Corticotropin-releasing hormone (CRH) is the principal regulator of the hypothalamic-pituitary-adrenal (HPA) axis and an activator of the sympathoadrenal (SA) and systemic sympathetic (SS) systems. Mental disorders, including major depression and, more recently, Alzheimer's disease have been associated with dysregulation of the HPA axis and the SA/SS systems. Treatment of rats or monkeys with the novel CRH receptor type 1 (CRH-R1) antagonist antalarmin inhibits the HPA and/or the SA/SS axes. This is the first study to examine the potential direct effect of antalarmin on human adrenal function. Adrenocortical and adrenomedullary cells were characterized by double-immunohistochemistry with anti-17 alpha hydroxylase (cortical cells) and anti-chromogranin A (chromaffin cells). Expression of CRH, ACTH, CRH type I and type II receptor mRNA were analyzed by reverse-transcription (RT) PCR. Human adrenal cortical and/or chromaffin cells in co-culture were incubated with CRH, antalarmin, and both CRH and antalarmin in vitro. Exposure of these cells to corticotropin or vehicle medium served as positive and negative controls, respectively. Cortical and chromaffin tissues were interwoven in the human adrenals, and both in situ and in the co-culture system the endocrine cell types were in close cellular contact. ACTH, CRH, and CRH-R1 and CRH-R2 mRNAs were expressed in the human adrenal as determined by RT-PCR. CRH (10-8 M) led to a moderate increase of cortisol release (145.7 +/- 20.0%) from cortical and chromaffin adrenal cells in co-culture. This effect corresponded to 41.8% of the maximal increase induced by ACTH (10-8 M). The action of CRH was completely inhibited by antalarmin. CRH, ACTH, and both CRH-R1 and CRH-R2 mRNAs are expressed in the adult human adrenal gland. CRH stimulates cortisol production in cortical and chromaffin cell co-cultures. This effect is blocked by antalarmin, a selective CRH-R1 receptor antagonist, suggesting that CRH-R1 receptors are involved in an intraadrenal CRH/ACTH control system in humans.
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PMID:Effects of a novel corticotropin-releasing-hormone receptor type I antagonist on human adrenal function. 1082 40

Hippocampus-mediated glucocorticoid negative feedback is thought to be relevant to the pathophysiology of neuropsychiatric disorders, but no reliable method of measuring it in humans has been developed. Converging lines of evidence indicate that basal hypothalamic-pituitary-adrenal axis activity during the unstressed circadian trough is primarily regulated by this feedback process. To assess whether negative feedback can be demonstrated under these circumstances, we studied normal controls (n = 5) who were pretreated with metyrapone to lower their basal evening cortisol levels. On two separate occasions, in double-blind randomized order, subjects received an infusion of cortisol or of saline. Restoration of normal evening plasma cortisol by the cortisol infusion produced a drop in plasma adrenocorticotropin (ACTH) apparent in the last sample obtained at +200 min (p < 0.05). The ACTH response in schizophrenic patients (n = 4), whose mental illness may arise from hippocampal dysfunction, was relatively blunted compared to that seen in normals (p < 0.02). 11-Desoxycortisol levels paralleled the ACTH responses across conditions and subject groups. These preliminary data suggest that hippocampus-mediated glucocorticoid feedback can be measured in normal subjects and may provide an index of hippocampal dysfunction in neuropsychiatric patients.
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PMID:Adrenocorticotropin inhibition by restoration of normal evening cortisol levels: a measure of putative hippocampus-mediated glucocorticoid feedback in humans. 1087 1

The study of the neural substrates underlying stress and anxiety has in recent years been enriched by a burgeoning pool of genetic information gathered from rodent studies. Two general approaches have been used to characterize the interaction of genetic and environmental factors in stress regulation: the evaluation of stress-related behavioral and endocrine responses in animals with targeted deletion or overexpression of specific genes and the evaluation of changes in central nervous system gene expression in response to environmental perturbations. We review recent studies that have used molecular biology and genetic engineering techniques such as in situ hybridization, transgenic animal, and antisense oligonucleotide gene-targeting methodologies to characterize the function of corticotropin-releasing hormone (CRH) system genes in stress. The effects of genetic manipulations of each element of the CRH system (CRH, its two receptors, and its binding protein) on stress-related responses are summarized. In addition, the effects of stress (acute, repeated, or developmental) on CRH system gene expression are described. The results from these studies indicate that experimentally engineered or stress-induced dysregulation of gene expression within the CRH system is associated with aberrant responses to environmental contingencies. These results are discussed in the context of how CRH system dysfunction might contribute to stress-related psychopathology and are presented in conjunction with clinical findings of CRH system dysregulation in psychiatric illness. Finally, future research strategies (i.e., high-throughput gene screening and novel gene-targeting methodologies) that may be used to gain a fuller understanding of how CRH system gene expression affects stress-related functioning are discussed.
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PMID:Corticotropin-releasing hormone and animal models of anxiety: gene-environment interactions. 1113 59

The prevalence of chronic widespread pain in the general population in Israel was comparable with reports from the USA, UK, and Canada. Comorbidity with fibromyalgia (FM) resulted in somatic hyperalgesia in patients with irritable bowel syndrome. One sixth of the subjects with chronic widespread pain in the general population were also found to have a mental disorder. Mechanisms involved in referred pain, temporal summation, muscle hyperalgesia, and muscle pain at rest were attenuated by the N-methyl-D-aspartate (NMDA) antagonist, ketamine, in FM patients. Delayed corticotropin release, after interleukin-6 administration, in FM was shown to be consistent with a defect in hypothalamic corticotropin-releasing hormone neural function. The basal autonomic state of FM patients was characterized by increased sympathetic and decreased parasympathetic systems tones. The severity of functional impairment as assessed by the Medical Outcome Survey Short Form (SF-36) discriminated between patients with widespread pain alone and FM patients. Chronic fatigue syndrome (CFS) occurred in about 0.42% of a random community-based sample of 28,673 adults in Chicago, Illinois. A significant clinical overlap between CFS and FM was reported. Cytokine dysregulation was not found to be a singular or dominant factor in the pathogenesis of CFS. A favorable outcome of CFS in children was reported; two thirds recovered and resumed normal activities. No major therapeutic trials in FM and CFS were reported over the past year.
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PMID:Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome. 1122 36

Many psychiatric disorders, including depression, post-traumatic stress disorder and other anxiety disorders, result from an interaction between genetic factors and exposure to a sufficiently sensitizing environmental stressor. The inbred Wistar Kyoto (WKY) rat strain has been proposed as a model of stress vulnerability, exhibiting an exaggerated hypothalamic-pituitary-adrenal (HPA) response to stress and susceptibility to gastric ulceration. Previously, we showed that stress-activation of the brain noradrenergic system was deficient in WKY rats, and they lacked noradrenergic facilitation of the HPA response in the lateral bed nucleus of the stria terminalis (BSTL), compared to outbred Sprague-Dawley (SD) controls. Deficient modulatory function of the noradrenergic system may contribute to the stress susceptibility of WKY rats. Thus, we investigated the influence of a sensitizing stimulus, chronic intermittent cold exposure, on neuroendocrine and noradrenergic stress reactivity, and on noradrenergic facilitation of the HPA response in these two strains. Chronic cold exposure (7 days, 4 h/day, 4 degrees C) potentiated activation of the HPA axis by acute immobilization stress, assessed by measuring plasma adrenocorticotropic hormone (ACTH), in both strains, although to a greater extent in WKY rats, and enhanced stress-induced norepinephrine (NE) release in BSTL of WKY but not SD rats. We then compared the influence of chronic cold exposure on noradrenergic modulation of the HPA stress response in BSTL, by measuring changes in acute stress-induced elevation of plasma ACTH after microinjecting the alpha(1)-adrenoreceptor antagonist benoxathian into the BSTL. As shown previously, benoxathian attenuated stress-induced ACTH secretion in control SD but not control WKY rats. After chronic cold, the ACTH response to acute stress was attenuated by benoxathian administration into BSTL of both strains, such that the WKY response was not different from that of SD rats. Thus, chronic cold not only sensitized the release of NE in BSTL of WKY rats, but also restored noradrenergic facilitation of their already-elevated HPA response. Such functional sensitization of a previously-deficient facilitatory system may be one mechanism whereby exposure to repeated or severe stress may induce pathologic dysregulation of the stress response in susceptible individuals, resulting in psychiatric illness.
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PMID:Chronic cold stress sensitizes brain noradrenergic reactivity and noradrenergic facilitation of the HPA stress response in Wistar Kyoto rats. 1269 37

There is compelling evidence for the involvement of hypothalamic-pituitary-adrenal (HPA) axis abnormalities in depression. Growing evidence has suggested that the combined dexamethasone (DEX)/corticotropin-releasing hormone (CRH) test is highly sensitive to detect HPA axis abnormalities. We organized a multicenter study to assess the DEX/CRH test as a state-dependent marker for major depressive episode in the Japanese population. We conducted the DEX/CRH test in 61 inpatients with major depressive episode (Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM-IV)) and 57 healthy subjects. In all, 35 patients were repeatedly assessed with the DEX/CRH test on admission and before discharge. The possible relationships between clinical variables and the DEX/CRH test were also examined. Significantly enhanced pituitary-adrenocortical responses to the DEX/CRH test were observed in patients on admission compared with controls. Such abnormalities in patients were significantly reduced after treatment, particularly in those who underwent electroconvulsive therapy (ECT) in addition to pharmacotherapy. Age and female gender were associated with enhanced hormonal responses to the DEX/CRH test. Severity of depression correlated with DEX/CRH test results, although this was explained, at least in part, by a positive correlation between age and severity in our patients. Medication per se was unrelated to DEX/CRH test results. These results suggest that the DEX/CRH test is a sensitive state-dependent marker to monitor HPA axis abnormalities in major depressive episode during treatment. Restoration from HPA axis abnormalities occurred with clinical responses to treatment, particularly in depressed patients who underwent ECT.
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PMID:Assessment of the dexamethasone/CRH test as a state-dependent marker for hypothalamic-pituitary-adrenal (HPA) axis abnormalities in major depressive episode: a Multicenter Study. 1612 48

Anorexia Nervosa (AN) is a psychiatric disorder characterized by the classic triad: amenorrhea, weight loss, and behavioral changes. It is generally seen in young, white women under 25 and is particularly common in adolescence. The mortality of the disease varies between 5.1% and 13%. The endocrine changes associated with AN have been studied in depth and provide strong evidence for hypothalamic dysfunction. All are secondary and reverse with weight gain. In general, gonadotropin (FSH, LH) levels are decreased in patients with AN, as well as the response to Gonadotropin releasing hormone (GnRH). Fasting growth hormone levels are elevated, but the stimulated response of Growth hormone (GH) to Growth hormone releasing hormone (GHRH) is normal and inversely correlated to body weight. Serum Growth hormone binding protein (GHBP), insulin growth factor I (IGF-I) and IGF binding protein (IGFBP) - 3 levels are all significantly decreased in patients with AN and return to normal with refeeding. IGFBP-1 and 2 are increased and return also to normal with weight gain. Serum IGF-II is decreased but not significantly. The IGFBP-3 proteolytic activity is normal. Thyroxine (T4) and Triiodothyronine (T3) while reverse T3 (rT3) is elevated. Thyrotropin stimulating hormone (TSH). TSH levels are normal with a delayed response to thyrotropin releasing hormone (TRH). Cortisol levels are normal or elevated as well as urinary free cortisol. Corticotropin (ACTH) levels are normal with decreased response to Corticotropin releasing hormone (CRH). Dexamethasone suppression test is abnormal. Sex steroids are decreased. Finally leptin levels are decreased in patients with AN while ghrelin levels are elevated. Both leptin and ghrelin levels return to control values after renutrition.
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PMID:Endocrine abnormalities in Anorexia Nervosa. 1643 12

Individuals with melancholic major depression exhibit basal hypercortisolism and an attenuated ACTH response to exogenous corticotropin-releasing hormone (CRH) infusion. Given the greater incidence of depression in children of depressed parents, we examined the ACTH and cortisol responses to ovine CRH (oCRH) infusion in 63 adolescent offspring of mothers with major depression, bipolar illness, or no psychiatric illness. Psychiatric and observational assessments of these families had been conducted over the course of 10 years preceding this study. We examined the children's responses to CRH in relation to maternal characteristics and family environment and found the following: (a) cortisol responses were negatively related to chronic family stress and (b) offspring of depressed mothers with an avoidant personality disorder showed an exaggerated ACTH response. In addition, adolescents in late puberty (Tanner 4 and 5) had lower ACTH and cortisol responses to oCRH infusion than those in early puberty. Further, offspring with early histories of mood problems, and those who developed major depressive disorder as young adults, did not exhibit basal hypercortisolism but did show an attenuated ACTH response to CRH. Our results add to the growing body of literature showing the influence of maternal characteristics and environmental factors on hypothalamic-pituitary-adrenal axis patterns in children.
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PMID:Maternal and environmental factors influence the hypothalamic-pituitary-adrenal axis response to corticotropin-releasing hormone infusion in offspring of mothers with or without mood disorders. 1647 58


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