Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chronic alcohol consumption has been shown to be associated with abnormalities in the regulation of the hypothalamo-pituitary-adrenal (HPA) axis in humans. However, conflicting data exist in the literature, with particular regard to studies performed in actively drinking or withdrawn alcoholics; in addition, the frequent presence of depressive disturbances in such patients may importantly affect the neuroendocrine findings. In this study, we investigated HPA function in 12 male alcoholics, in whom the presence of depression and other possible confounding factors was excluded, during the first and second weeks after cessation of ethanol intake. The plasma corticotropin (adrenocorticotropic hormone, ACTH) and cortisol levels in response to both a stimulation test with human corticotrophin-releasing hormone (CRH; 100 micrograms IV) and an insulin (0.15 UI/kg IV)-induced hypoglycaemia (ITT) were measured; the cortisol response to a standard overnight dexamethasone (1 mg) suppression test (DST) was also tested. While the mean baseline ACTH and cortisol levels, measured in the morning (0800-0830 h), were not different from those of controls, ACTH and cortisol responses to the CRH test were markedly reduced (area of secretion p < .01 and p < .05, compared to controls). Similarly, the patient group showed an almost absent ACTH and cortisol release following insulin infusion (area of secretion p < .01 compared to controls, in either case). In four patients, non-suppression of plasma cortisol levels was seen on the DST, but no significant difference from normal suppressors was noted as far as the clinical features were concerned. These findings suggest that impaired hypothalamic and pituitary responsiveness, unrelated to depressive disturbances, occurs in recently withdrawn chronic alcoholics. While the possible influence of the alcohol withdrawal syndrome should be taken into account, such a pattern may be due to increased activity of the HPA axis, even in the face of preserved basal adrenal secretion. Whether these findings reflect a direct effect of sustained ethanol exposure on the components of the HPA axis, or a non-specific marker of impaired adaptation in chronic alcoholics, deserves further investigation.
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PMID:An assessment of hypothalamo-pituitary-adrenal axis functioning in non-depressed, early abstinent alcoholics. 881 25

Adrenocorticotropic hormone (ACTH) and cortisol secretion have been shown to be abnormal in approximately half of depressed patients. Information from pituitary and adrenal studies suggests that the locus of this dysregulation is at or above the level of the hypothalamus; however, direct evidence from provocative studies of the hypothalamic corticotropin releasing hormone (CRH) neuron does not exist. The current study was designed to stimulate hypothalamic CRH release using the opiate antagonist naloxone in patients with depression and elevated urinary-free cortisols as well as healthy and psychiatric controls. All subjects received naloxone and placebo on separate days in a double-blinded, randomized fashion at a dose determined previously to reliably induce significant increases in ACTH and cortisol secretion. No significant differences were noted among groups. We conclude that although naloxone is an effective central stimulant of the hypothalamic CRH neuron, stimulation of the hypothalamic CRH neuron with naloxone does not provide evidence of dysregulation of the HPA axis in depression.
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PMID:Naloxone-induced pituitary-adrenal activation does not differ in patients with depression, obsessive compulsive disorder, and healthy controls. 884 Mar 57

Through expression of a glucocorticoid receptor (GR) antisense RNA in brain, we have produced transgenic mice with an hyperactive hypothalamic-pituitary-adrenocortical (HPA) system similar to that seen in depressed patients. This model supports the hypothesis that disturbed corticosteroid receptor regulation could be the primary factor responsible for both the CRH/AVP hyperdrive that leads to increased activity of the HPA system, and the premature escape from the cortisol suppressant action of dexamethasone seen in affective disorders. Although normalisation of the hyperactive HPA system occurs during successful antidepressant therapy of depressive illness, these improvements do not correlate with changes in monoaminergic neurotransmitter systems, suggesting that unknown mechanisms of action may be operative. Work from my laboratory was the first to show that different types of antidepressants increased glucocorticoid receptor (GR) mRNA. We found increased GR mRNA levels irrespective of the preferential inhibitory action of antidepressant on the monoamine neurotransmitter re-uptake and showed increased GR gene transcription in antidepressant-treated mouse fibroblast cells that do not possess monoamine re-uptake mechanisms. We measured changes in glucocorticoid response in cells transfected with a glucocorticoid-sensitive reporter plasmid (MMTV-CAT) and observed increased glucocorticoid-stimulated CAT activity when the cells were treated with antidepressant. A different chimaeric gene construct consisting of a fragment of the GR gene promoter region fused to the CAT gene allowed more direct measurement of antidepressant action and increased CAT activity was also seen when cells transfected with this construct were treated with antidepressant. Finally, GR mRNA concentration and glucocorticoid binding activity were increased in brain tissues of animals chronically treated with antidepressant. The time course of antidepressant actions on corticosteroid receptors coincides with their long-term actions on HPA system activity and follows closely that of clinical improvement of depression. This suggests that antidepressant-induced changes in brain corticosteroid receptors may underlie the observed simultaneous decrease in circulating ACTH and corticosterone levels and the decreased adrenal size. Some of these effects may be mediated through CRH since, in antidepressant-treated transgenic mice hypothalamic CRH mRNA levels were decreased. From this work we have formulated the hypothesis that a primary action of antidepressants could be the stimulation of corticosteroid receptor gene expression that renders the HPA system more susceptible to feedback inhibition by cortisol. The resultant decrease in HPA system activity could induce secondary changes in glucocorticoid-sensitive gene expression and lead to redressment of neurotransmitter imbalance. This work opens up a completely new insight into antidepressant drug action and suggests a line of approach to the development of new drugs by focusing on this action.
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PMID:Modulation of glucocorticoid receptor gene expression by antidepressant drugs. 885 29

1. Eating disorders can be found in several psychiatric pathologies: schizophrenia, delusional disorder (somatic type), bipolar disorders, major depressive disorder, borderline personality disorder, generalized anxiety disorder, body dysmorphic disorder, somatization disorder and conversion disorder. 2. Although their clinical features have been defined, relatively little is known about the role of neurobiological patterns in the pathogenesis of these disorders. Several CNS neurotransmitters and neuromodulators are involved in the regulation of eating behavior in animals and have been implicated in symptoms such as depression and anxiety often observed in patients with eating disorders. The authors will review some studies on NA, DA, 5-HT, beta-endorphins, CRH, VP, OT, CCK, NPY and PYY involved in eating disorders. Furthermore, we will highlight some of the studies on drug therapy of eating disorders taking into account the effects of these agents on neurotransmitters and neuromodulators. 3. Antidepressant drugs have long been used for anorexia nervosa and bulimia, these disorders been claimed to be affective equivalent. Antidepressant agents seem to be effective in reducing the frequency of binge-eating episodes, purging behavior and depressive symptomatology. It is notable that antidepressant agents have been proved to be effective in patients with chronic bulimic symptoms, even in cases persisting for many years and in patients who had repeatedly failed courses of alternative therapeutic approaches. In all of the positive studies, antidepressant agents appeared effective even in bulimic subjects who did not display concomitant depression. 4. Few controlled studies on use of medications for anorexia nervosa have been published. Central serotonergic receptor-blocking compounds such as cyproheptadine cause marked increase in appetite and body weight. Zinc supplementation or cisapride could be a therapeutic option in addition to psychological and other approaches in anorexia nervosa. 5. There is no therapy as yet which is fully effective in alimentary disorders. Psychotropic drugs give some relief from symptoms, but they cannot cure the disorders. An integrated approach, either pharmacological or psychological, is still recommendable.
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PMID:Neurobiological and psychopharmacological basis in the therapy of bulimia and anorexia. 886 Nov 89

This study examined the hypothesis that experimentally induced corticosteroid resistance in the brain would lead to adaptations in the activity of the hypothalamic-pituitary-adrenal (HPA) axis similar to the endocrine features of the endogenous resistance accompanying the pathogenesis of depression. For this purpose, the glucocorticoid antagonist RU 38486 (aGC) was infused intracerebroventricularly (i.c.v.) (100 ng/h) via Alzet minipumps for several days. During this chronic receptor blockade, parameters for basal and stress-induced HPA activity were measured in a longitudinal study design. Chronic i.c.v. infusion of the aGC did not affect basal morning levels of ACTH and corticosterone. During the afternoon phase of the circadian cycle, the aGC caused gradual and sequential changes in the HPA axis. After aGC infusion, the circadian rise of ACTH levels was enhanced in the afternoon of day 1, but was normal on subsequent days. For corticosterone, basal afternoon levels towards the diurnal peak were increased at days 1, 3, and 4 in aGC-treated rats. On day 2, in contrast, corticosterone levels did not differ from vehicle-infused controls. Paraventricular CRH messenger RNA, as measured at day 4, was not altered by aGC treatment. After 10 days of aGC treatment, the adrenal weight was increased, and the sensitivity of adrenocortical cells in vitro to ACTH was enhanced. Corticosteroid receptor binding in vitro in hippocampus, hypothalamus, and pituitary was not different between the aGC and vehicle-treated rats. In a second series of experiments, the HPA responsiveness to the stress of a novel environment at day 2 in the morning was increased after chronic aGC infusion, at a time basal hormone levels were not affected. The data show that 1) chronic i.c.v. infusion of aGC readily enhances the amplitude of circadian corticosterone changes, presumably by increasing the adrenocortical sensitivity to ACTH; 2) chronic aGC-treated animals show an enhanced ACTH and corticosterone response to stress, which is delayed in termination; 3) corticosteroid receptor expression, basal CRH messenger RNA, and ACTH levels are not altered after prolonged chronic aGC treatment. It is concluded that, over a period of a few days, aGC-induced corticosteroid resistance triggers a sequelae of pituitary-adrenal adaptations ultimately resulting in hypercorticism. Paradoxically, however, this hypercorticism develops because of increased peak levels of corticosteroid hormone rather than through elevated trough levels as is commonly observed during depressive illness.
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PMID:Chronic brain glucocorticoid receptor blockade enhances the rise in circadian and stress-induced pituitary-adrenal activity. 889 66

The hypothesis is proposed of a new subtype of depression named: stressor-precipitated, cortisol-induced, serotonin-related, anxiety/aggression-driven depression (SeCA depression). Biologically, these patients are characterized by impaired 5-HT synthesis and reduced 5-HT1A receptor sensitivity. Under normal conditions these functions proceed marginally; in times of stress they easily fail, due to sustained overproduction of cortisol. Psychopathologically this depression type shows the following characteristics: anxiety and aggression, not mood lowering, heralding a depressive episode; the personality structure shows 'character neurotic' impairments and tolerance for (certain) traumatic life events is low. As specific therapeutic agents selective 5-HT1A agonists and cortisol or CRH antagonists are proposed. Prophylactically, maintenance treatment with 5-HT1A agonists seems indicated as well as psychological interventions to increase the stressor threshold.
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PMID:Faulty cortisol/serotonin interplay. Psychopathological and biological characterisation of a new, hypothetical depression subtype (SeCA depression) 970 3

Decreased feedback control of the hypothalamic-pituitary-adrenocortical (HPA) system as revealed by the combined dexamethasone and corticotropin-releasing hormone (DEX-CRH) test has been documented in the vast majority of patients with affective disorders. This finding was interpreted as a failure at the level of the glucocorticoid receptor (GR)-mediated feedback action, which apparently fails to restrain HPA activity in the presence of elevated plasma corticosteroid levels. To test this hypothesis we conducted the DEX/CRH test using increasing doses of DEX in order to establish a dose-response relationship. We used three different DEX doses (0.75, 1.5, 3.0 mg) in three groups of depressed patients and controls. As expected, increasing DEX doses were associated with decreasing amounts of adrenocorticotropin (ACTH) and cortisol being released after CRH injection. However, dose-response curves for both plasma ACTH and cortisol concentrations were shifted to higher area under the curve (AUC) values among patients compared to controls. Pretreatment with 0.75 and 1.5 mg DEX produced significantly higher AUC values for both plasma ACTH and cortisol values among patients. These differences became less obvious with the higher DEX doses, indicating that the dose of 1.5 mg used in the majority of clinical studies so far is well suited to differentiate between healthy controls and patients. The reported data here are consistent with the hypothesis that an altered GR capacity or function underlies the exaggerated HPA activity in depression.
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PMID:Corticosteroid receptor function is decreased in depressed patients. 908 3

Atopic eczema is a chronic inflammatory skin disease which shares some psychological and neuroendocrine disturbances with patients suffering from depression. In view of recent findings of an attenuated response of the hypothalamic-pituitary-adrenal (HPA) system in patients with atopic eczema during a human corticotropin-releasing hormone (hCRH) challenge paradigm fourteen consecutive non-specifically trained in-patients with atopic eczema (8 men, 6 women) and an age-matched control group (8 men, 6 women) performed exhausting incremental graded bicycle exercise to evaluate cortisol, adrenocorticotropin (ACTH), beta-endorphin, epinephrine and norepinephrine releases induced by physical stress. The exercise yielded significant increases in cortisol, ACTH, beta-endorphin, epinephrine and norepinephrine concentrations in both groups. Patients with severe eczema displayed a significantly lower increase in norepinephrine levels when compared with the less affected patient group. In contrast to the challenge with exogenous hCRH no substantial difference in the net responses of ACTH and cortisol could be detected between patients with atopic eczema and controls using the physical stress paradigm. These substantial differences in the net outcome between both challenges may be related to the potential synergizing effects of various neuropeptides, e.g. CRH and vasopressin, when activating the HPA system by challenges at a suprapituitary site which may override subtle disturbances in the responsivity of the HPA system as revealed by CRH challenge alone in patients with atopic eczema.
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PMID:Physical stress-induced secretion of adrenal and pituitary hormones in patients with atopic eczema compared with normal controls. 908 93

The hypercortisolism of melancholic depression is thought to reflect hypothalamic hypersecretion of CRH and may be related to the hyperarousal associated with this syndrome. Although chronic administration of imipramine to experimental animals significantly decreases CRH messenger RNA levels in the paraventricular nucleus, it is generally thought that resolution of hypercortisolism following recovery from depression is related to the improvement in mood and decrease in anxiety that accompanies recovery rather than an intrinsic effect of imipramine. The present study was designed to explore whether chronic imipramine administration to healthy, nondepressed volunteers is associated with effects on hypothalamic-pituitary-adrenal (HPA) axis function. We studied basal and provocative measures of HPA axis function in 14 healthy volunteers before and after 6 weeks of imipramine treatment at therapeutic doses. Imipramine was associated with decreased responses in peak ACTH and cortisol to ovine CRH and in peak ACTH to arginine vasopressin (P = 0.02, P = 0.003, and P = 0.02, respectively) without changes in indices of basal HPA axis function. These data are consistent with preclinical findings and support the hypothesis that imipramine has an intrinsic effect on central components of HPA axis function, potentially related to its therapeutic effects.
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PMID:Chronic imipramine is associated with diminished hypothalamic-pituitary-adrenal axis responsivity in healthy humans. 925 41

Patients with depression frequently have symptom clusters which point strongly to involvement of the hypothalamic-pituitary-adrenal (HPA) system as a relay station between neurocircuitries in the brain and peripheral hormone and autonomic nervous function. It has been proposed that this increased, state-dependent hyperactivity of the HPA-system in depression is probably initiated and/or maintained by the combination of enhanced central production of CRH and desensitization of the binary, glucocorticoid receptor binding system in the hippocampus, which is the central regulator of HPA system activity. In a first series of studies a refined neuroendocrine test to probe the integrity of HPA system status--the combined dexamethasone suppression/CRH challenge (DEX/CRH) test--was developed and the differential effects of aging and depressed psychopathology on DEX/CRH test outcome were described. In a second set of studies, the chronological relationship between improvement of psychopathology in depressed patients treated with antidepressants and normalization of the disturbed HPA system function in these patients was further elucidated. Given the evidence from animal studies, we conclude that antidepressants induce an up-regulation of hippocampal glucocorticoid receptor mRNA concentration, thus amplifying the negative feedback effect of glucocorticoids. This then results in the normalization of DEX/CRH test results observed in the depressed patients in our study. We further conclude that dampening of HPA system hyperactivity in depression by means of antidepressants is a conditio sine qua non for successful improvement of psychopathology.
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PMID:Anna-Monika-Prize paper. The hypothalamic-pituitary-adrenal system in depression. 952 78


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