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)

It has been hypothesized that corticotropin-releasing hormone (CRH) is an integral mediator in the pathophysiology of anorexia nervosa. This hypothesis is based on a) studies on patients with eating disorders which found elevated CRH levels in the cerebrospinal fluid and an abnormal response of the hypothalamopituitary (HYPAC) axis to intravenous CRH, and b) the discovery that the central administration of CRH to rats causes an acute anorectic state. Human and animal data supporting this hypothesis are reviewed, and important problems with the data base and the interpretation of these data are discussed. Appropriate directions for future research are highlighted.
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PMID:Corticotropin-releasing hormone: possible role in eating disorders. 269 Jan 92

Vasopressin (AVP) and oxytocin (OT) are hypothalamic neuropeptides having distinct peripherally and centrally directed cell populations. While principally responsible for the regulation of osmotic equilibrium, AVP also participates in stress-mediated adrenocorticotropic hormone (ACTH) release, and in consolidation and retrieval of aversively conditioned behaviors. OT is principally known for its role in parturition and lactation, but also has effects opposite of AVP, antagonizing stress-mediated ACTH release and impairing the consolidation and retrieval of aversively conditioned behaviors. Our group has demonstrated novel peripheral osmoregulatory defects in underweight anorexics, coupled with hypersecretion of AVP into the cerebrospinal fluid (CSF). Conversely, a relative reduction of CSF OT is seen in underweight anorexics. Speculatively, these reciprocal changes in neurohypophyseal peptides in the underweight anorexic may enhance the observed neuroendocrine and cognitive abnormalities. In addition, the alterations in CSF OT may occur as a consequence of the abnormal gastrointestinal function present during the acute stages of anorexia nervosa.
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PMID:Neurohypophyseal dysfunction: implications for the pathophysiology of eating disorders. 269 13

The discovery that the endogenous opioid peptides contribute to the modulation of appetitive behavior and neuroendocrine function has raised questions as to whether disturbances of opioids contributes to the pathophysiology of eating disorders. To assess central nervous system (CNS) beta-endorphin in patients with anorexia nervosa we measured cerebrospinal fluid (CSF) beta-endorphin concentrations before, and at intervals after weight correction. In addition, we measured three sister peptides (beta-lipotropin, adrenocorticotropic hormone (ACTH), and the N-terminal fragment) derived from the same precursor molecule, pro-opiomelanocortin (POMC) to determine whether possible disturbances might extend to sister peptides. Underweight anorectics (58 +/- 5% of average body weight (ABW), n = 10) had significantly lower CSF concentrations of all 4 peptides compared to healthy controls (102 +/- 10% ABW, n = 11). CSF concentrations of all 4 POMC-related peptides were found to be significantly increased when the same anorectics were restudied 4 to 6 weeks after weight gain (83 +/- 4% ABW). After weight gain, levels of CSF beta-endorphin, beta-lipotropin, and ACTH were similar to controls, whereas levels of CSF N-POMC remained significantly less than controls. Another group of women, previously underweight with anorexia nervosa, but weight-restored (93 +/- 11% ABW, n = 12) for greater than 1 year had CSF concentrations of all 4 POMC-related peptides that were similar to controls. We conclude that underweight anorectics have state-associated disturbances of CNS beta-endorphin as well as other POMC-related peptides. These abnormalities are part of the neurobiological syndrome of anorexia nervosa and may contribute to the characteristic alterations in behavior and neuroendocrine function.
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PMID:Reduced cerebrospinal fluid levels of immunoreactive pro-opiomelanocortin related peptides (including beta-endorphin) in anorexia nervosa. 282 41

The data on the status of the hypothalamic-pituitary-adrenal (HPA) axis in haemodialysis (HD) patients are conflicting. Moreover, a state reminiscent of Cushing's syndrome has been reported in this group of patients. Corticotropin-releasing hormone (CRH), that is produced by the hypothalamus and modulates the secretion of adrenocorticotropic hormone (ACTH), has been shown to be useful as a provocative test of the HPA axis. We investigated the effect of exogenous ovine CRH (oCRH) on plasma levels of ACTH and cortisol in 13 chronic HD patients. The plasma concentrations of immunoreactive CRH following oCRH administration were similar in patients and controls. In all patients, oCRH given intravenously as bolus injection caused a further increase in the already elevated levels of cortisol. The mean basal plasma levels of ACTH were within the normal range. There was, however, a blunted ACTH response to oCRH. We conclude that the HPA axis in chronic HD patients retains the ability to respond to exogenous oCRH. The patterns of the ACTH and cortisol response to this peptide resemble those observed in chronic stress (depression, anorexia nervosa). Besides, the kinetics of disappearance of oCRH indicate that the kidney may not be the major organ that metabolizes oCRH.
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PMID:Ovine corticotropin-releasing hormone stimulation test in patients with chronic renal failure: pharmacokinetic properties, and plasma adrenocorticotropic hormone and serum cortisol responses. 285 25

Considerable evidence exists of hypothalamic dysfunction in patients with anorexia nervosa and bulimia nervosa. This dysfunction is reflected in disturbances of endocrine function including abnormalities of gonadotropin, growth hormone, and corticotropin-releasing hormone secretion. Whereas these disturbances are generally reversed with nutritional rehabilitation and weight restoration, it is not evident to what extent nutritional factors are the primary etiology or whether they unmask an otherwise existing but compensated central disturbance. Similarly, endocrine disturbances may be a final common pathway in which disturbances of diet, weight, activity, stress, and mood as well as hypothalamic dysfunction are expressed.
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PMID:The endocrinology of anorexia nervosa and bulimia nervosa. 289 9

Clinical and biochemical data suggest a link between anorexia nervosa (AN) and primary affective disorders (PAD). In 14 female patients, aged 15-40 years, with 7-month to 11-year histories of AN, we studied circadian cortisol periodicity, response to the dexamethasone suppression test (DST), and plasma levels of beta-endorphin and beta-lipotropin before and after desimipramine therapy. Possible correlations were sought among neuroendocrine impairments, weight loss, and depressive symptomatology. Impaired circadian cortisol periodicity, blunted DST response, and increased beta-endorphin plasma levels, observed in a subgroup of patients, could not be related to weight loss, either before or after therapy. Instead, a trend toward a relationship between neuroendocrine impairments and depressive symptoms was observed before and after treatment.
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PMID:Neuroendocrine and psychopathological measures in anorexia nervosa: resemblances to primary affective disorders. 293 58

Clinical and biochemical findings link anorexia nervosa (AN) and primary effective disorders (PAD). Clonidine, an alpha 2-adrenoceptor agonist, has been shown to blunt growth hormone (GH) response and greatly lower plasma cortisol in PAD patients. We examined the GH, cortisol, and beta-endorphin (beta-EP) responses to an acute clonidine challenge (150 micrograms i.v. as a bolus) before and after 30 days of treatment with desmethylimipramine in 14 women with AN. Both before and after treatment, the AN patients showed normal plasma GH and cortisol responses, but an increased plasma beta-EP response. The increased beta-EP response in AN was independent of weight and depressive symptomatology. Our data indicate that alpha 2-adrenoceptors involved in the control of GH and adrenocorticotropic hormone are not altered in AN. The increased beta-EP response may indicate elevated opioid activity in the hypothalamo-pituitary system of AN patients.
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PMID:Clonidine stimulation in anorexia nervosa: growth hormone, cortisol, and beta-endorphin responses. 295 60

Pituitary-adrenocortical responses to the iv injection of 100 micrograms synthetic ovine corticotropin-releasing hormone (CRH) were studied in 13 patients with anorexia nervosa, and the concentrations of immunoreactive CRH in cerebrospinal fluid were measured in 7 of them. Mean basal levels of plasma ACTH and cortisol were 32 +/- 5 pg/ml (+/- SEM) and 21.1 +/- 1.5 micrograms/dl, respectively. The latter value was significantly higher than that in age-matched normal women (P less than 0.005). The mean increments of plasma ACTH and cortisol in response to CRH injection in those 13 patients were 21 +/- 5 pg/ml and 5.3 +/- 1.7 micrograms/dl, respectively, significantly lower than those in normal women (58 +/- 6 pg/ml and 15.3 +/- 7.7 micrograms/dl, respectively; P less than 0.005). When 4 patients were reexamined after weight gains of between 3 and 22 kg, their responses to the CRH injection increased. The mean concentration of immunoreactive CRH in the cerebrospinal fluid of seven patients was 30.8 +/- 3.9 pg/ml (+/- SEM), which was higher than the value of 18.4 +/- 1.1 pg/ml (P less than 0.005) in control subjects with cervical spondylosis. These findings suggest the possibility that hypersecretion of CRH may occur in patients with anorexia nervosa.
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PMID:The responses of plasma adrenocorticotropin and cortisol to corticotropin-releasing hormone (CRH) and cerebrospinal fluid immunoreactive CRH in anorexia nervosa patients. 300 Nov 25

To study the pathophysiology of hypercortisolism in patients with anorexia nervosa, we examined plasma ACTH and cortisol responses to ovine corticotropin-releasing hormone before and after correction of weight loss. We also studied patients with bulimia whose weight was normal, since this disorder has been suspected to be a variant of anorexia nervosa. Before their weight loss was corrected, the anorexic patients had marked hypercortisolism but normal basal plasma ACTH. The hypercortisolism was associated with a marked reduction in the plasma ACTH response to corticotropin-releasing hormone. When these patients were studied three to four weeks after their body weight had been restored to normal, the hypercortisolism had resolved but the abnormal response to corticotropin-releasing hormone remained unchanged. On the other hand, at least six months after correction of weight loss their responses were normal. The bulimic patients whose weight was normal also had a normal response to corticotropin-releasing hormone. We conclude that in underweight anorexics, the pituitary responds appropriately to corticotropin-releasing hormone, being restrained in its response by the elevated levels of cortisol. This suggests that hypercortisolism in anorexics reflects a defect at or above the hypothalamus. The return to eucortisolism soon after correction of the weight loss indicates resolution of this central defect despite persistence of abnormalities in adrenal function.
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PMID:Abnormal hypothalamic-pituitary-adrenal function in anorexia nervosa. Pathophysiologic mechanisms in underweight and weight-corrected patients. 301 Jan 9

To study the effects of physical conditioning on the hypothalamic-pituitary-adrenal axis, we examined the plasma ACTH, cortisol, and lactate responses in sedentary subjects, moderately trained runners, and highly trained runners to graded levels of treadmill exercise (50, 70, and 90 percent of maximal oxygen uptake) and to intravenous ovine corticotropin-releasing hormone (1 microgram per kilogram of body weight). Basal evening concentrations of ACTH and cortisol, but not of lactate, were elevated in highly trained runners as compared with sedentary subjects and moderately trained runners. Exercise-stimulated ACTH, cortisol, and lactate responses were similar in all groups and were proportional to the exercise intensity employed. These responses, however, were attenuated in the trained subjects when plotted against applied absolute workload. Only the highly trained group had diminished responses of ACTH and cortisol to ovine corticotropin-releasing hormone, consistent with sustained hypercortisolism. We conclude that physical conditioning is associated with a reduction in pituitary-adrenal activation in response to a given workload. Alterations of the hypothalamic-pituitary-adrenal axis consistent with mild hypercortisolism and similar to findings in depression and anorexia nervosa were found only in highly trained runners. Whether these alterations represent an adaptive change to the daily stress of strenuous exercise or a marker of a specific personality profile in highly trained athletes is unknown.
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PMID:Acute hypothalamic-pituitary-adrenal responses to the stress of treadmill exercise. Physiologic adaptations to physical training. 303 4


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