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

The neuropeptide alpha-melanocyte stimulating hormone [alpha-MSH(1-13)] occurs in the pituitary, brain, skin and other tissues and receptors for this molecule are likewise widespread. In previous research, this tridecapeptide, which shares its amino acid sequence with ACTH(1-13), was shown to have both potent antipyretic activity and a role in the endogenous control of the febrile response. alpha-MSH(1-13) and its COOH-terminal tripeptide were subsequently found to inhibit inflammation induced by general stimuli such as topical application of an irritant. The aim in the present experiments was to determine if these peptides can inhibit acute inflammatory responses induced in mice by injection of individual cytokines, endogenous pyrogen (EP), a natural cytokine mixture, and other mediators of inflammation. Inflammation induced in the mouse ear by rIL-1 beta, rIL-6 or rTNF-alpha was inhibited by alpha-MSH and a D-valine-substituted analog of alpha-MSH(11-13) whereas substantial doses of alpha-MSH(1-13) did not alter inflammation induced by LTB4, PAF and IL-8. Both peptides inhibited edema caused in the mouse paw by local injection of EP. The results indicate that alpha-MSH molecules antagonize the actions of certain cytokine mediators of inflammation, consistent with previous observations of anti-cytokine activity of these peptides. Failure to inhibit edema caused by LTB4, PAF and IL-8 suggests that, in inflammation induced by general stimuli, such as EP, the peptides act prior to the release of these mediators of the inflammatory response. Because of the anticytokine/anti-inflammatory actions of the alpha-MSH molecules they may be useful in understanding the cytokine network and for treatment of inflammatory diseases.
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PMID:Alpha-MSH peptides inhibit acute inflammation induced in mice by rIL-1 beta, rIL-6, rTNF-alpha and endogenous pyrogen but not that caused by LTB4, PAF and rIL-8. 132 96

Dopaminergic neuron controls CNS functions such as meso-limbic, striato-nigral and tubero-infundibular systems. The purpose of the present study is the evaluation of the hypothalamic dopaminergic neuron activity in neuro-degenerative disorders. alpha-melanocyte-stimulating hormone (alpha-MSH) is synthesized in the arcuate nucleus and lateral part of the hypothalamus, and its secretion is under the inhibitory control of the dopaminergic neuron both in the hypothalamus and pituitary. alpha-MSH-like-immunoreactivity (alpha-MSH-LI) in CSF is thought to be representative to the dopaminergic neuron activity in the hypothalamus. We therefore evaluated CSF levels of alpha-MSH-LI in spinocerebellar degenerations and extrapyramidal diseases. The subjects are 11 patients with Parkinson's disease, 16 with Shy-Drager syndrome (SDS), 16 with cerebellar cortical atrophy, 3 with Machado-Joseph disease, 3 with dentato-rubro-pallido-luysian atrophy and 2 with Huntington's disease as well as 24 controls. All patients with Parkinson's disease were administered levodopa and carbidopa. CSF was sampled through lumbar puncture in the morning. After the centrifugation, supernatant of CSF was stored at -40 degrees C until used. alpha-MSH in CSF was extracted by Rainero's method and measured by RIA. alpha-MSH-LI levels in control was 23.9 +/- 2.6 pg/ml (mean +/- SD). The significant elevation was observed in Parkinson's disease (40.3 +/- 7.5, p less than 0.001) and SDS (42.3 +/- 9.4, p less than 0.001). The levels showed not significant correlation with age, duration of illness or severity of autonomic disorder. Most of other diseases demonstrated the levels within normal range.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Abnormality of hypothalamic dopaminergic system in neuro-degenerative diseases--evaluation of alpha-melanocyte-stimulating hormone-like immunoreactivity in cerebrospinal fluid]. 176 56

Lyso-platelet-activating factor (lyso-PAF): acetyl-CoA acetyltransferase (EC 2.3.1.67) enzyme activity was characterized for the first time in bovine adrenocortical tissue. It was found to be associated with the microsomal membrane fraction, in which it exhibited a specific activity of 0.4 nmol/min per mg of protein and catalytic properties similar to those described in other cell types. The adrenocortical acetyltransferase activity was increased by 2-3-fold on incubation of the preparation with purified protein kinase C (PKC) under phosphorylating condition. This activation was optimal after 5 min of incubation and paralleled an increase in PKC-catalysed 32P incorporation into microsomal proteins. Both acetyltransferase activation and protein phosphorylation were dependent on the presence of Ca2+ and phospholipids, and were blocked in the presence of the potent PKC inhibitor H-7. In the intact adrenocortical cell, angiotensin II and a potent phorbol ester (phorbol 12-myristate 13-acetate) were able to rapidly induce an increase in the biosynthesis of PAF, which was mostly released into the extracellular medium. These data suggest that bovine adrenocortical lyso-PAF acetyltransferase may be regulated by a PKC-dependent activation pathway, whereas no evidence for an additional adrenocorticotropin/cyclic AMP-dependent stimulation process was obtained in this cell type. Bovine adrenocortical cell membrane preparations were shown to possess high-affinity PAF-binding sites (Kd approximately 0.5 nM). Altogether, these observations suggest that PAF production and release may play a role in the autocrine or paracrine control of adrenocortical cell activation.
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PMID:Production of platelet-activating factor is a component of the angiotensin II-protein kinase C activation pathway in bovine adrenocortical cells. 188 37

To examine the effect of platelet-activating factor (PAF-acether) on pro-opiomelanocortin (POMC)-related peptides and on the hypothalamo-pituitary-adrenal axis, we administered PAF-acether and BN 52021, a selective PAF-acether antagonist, to freely moving rats. Minipumps loaded with either PAF-acether (30 micrograms/kg) or the vehicle alone were connected to the jugular vein for 7 days and positioned under the back skin of rats. A group of animals treated with PAF-acether also received 15 mg/kg of BN 52021 orally twice a day. In vivo treatment with PAF-acether alone or in association with BN 52021 did not affect the hypothalamic concentrations of corticotropin-releasing factor (CRF), alpha-melanocyte-stimulating hormone (alpha-MSH) and beta-endorphin. Using a perifusion system for rat hypothalamic slices, we did not observe any effect of PAF-acether on spontaneous or potassium-induced release of alpha-MSH in vitro. In addition, treatment of rats with PAF-acether alone or in association with BN 52021 did not modify the alpha-MSH or beta-endorphin concentration in the neurointermediate lobe of the pituitary. In contrast, in vivo administration of PAF-acether caused a significant reduction of ACTH concentration in the anterior lobe of the pituitary and a marked decrease in the corticosterone level in plasma and adrenal glands. The inhibitory effect of PAF-acether was reversed by concomitant administration of BN 52021. The ineffectiveness of PAF-acether to modulate in vitro ACTH release from perifused anterior pituitary fragments ruled out a direct effect of PAF-acether on corticotrophs. These findings support the view that PAF-acether exerts a specific inhibitory effect on the hypothalamo-pituitary-adrenal axis.
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PMID:Effect of platelet-activating factor on hypothalamic and hypophyseal pro-opiomelanocortin-related peptides and hypothalamo-pituitary-adrenal axis in the rat. 215 5

In summary, 5HT, ACh, NE, E and DA appear to stimulate hypothalamic CRH secretion whereas activation of the GABA/BZD system seems to decrease the responsivity of the CRH neuron to stimulatory neurotransmitters (Fig. 6). Hypothalamic CRH released from the hypothalamic neuron not only activates the HPA axis, but also stimulates the locus coeruleus-norepinephrine system (LC) and the central sympathetic system (CSS). CRH also induces secretion of hypothalamic POMC gene-derived peptides, such as ACTH, beta-EP, alpha-MSH and CLIP. These peptides as well as CRH itself, decrease the responsivity of the CRH neuron to stimulatory inputs. In addition, glucocorticoids restrain the activity of both the CRH neuron and the locus coeruleus and may also inhibit the secretion of POMC gene-derived peptides by the POMC neurons of the arcuate nucleus. Hypothalamic CRH secretion is regulated also by a number of mediators of the immune response, such as IL-1, IL-2, TNF-alpha and PGF2 alpha, PAF and EGF. Although the physiologic significance of this regulation is largely unknown, it is tempting to speculate that cytokines and mediators of inflammation released in vivo may activate the HPA axis to trigger a glucocorticoid-mediated counter-regulatory mechanism to restrain the immune system (Fig. 7). (Formula: see text). Fig. 7. Schematic representation of the interactions between the HPA axis and the immune system. Continuous lines represent stimulatory inputs and interrupted lines represent inhibitory inputs. In conclusion, our in vitro hypothalamic organ culture system allowed us to examine the regulation of CRH secretion in a direct and specific manner. Some of our observations may help with better understanding of the role played by CRH in the complex symptomatology of stress. In making extrapolations and interpretations from the in vitro data, however, we should try to keep in mind the words of Claude Bernard, "... If we break up a living organism by isolating its different parts it is only for the sake of ease in analysis and by no means in order to consider them separately. Indeed when we wish to ascribe to a physiological quality its value and true significance we must always refer it to this whole and draw our final conclusions only in relation to the effects in the whole".
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PMID:Regulation of rat hypothalamic corticotropin-releasing hormone secretion in vitro: potential clinical implications. 290 18

Four neuropeptides; cerebellin, corticotropin-releasing hormone (CRH), neuropeptide Y and somatostatin were studied by radioimmunoassay in the postmortem human brains obtained from three patients with olivopontocerebellar atrophy (OPCA) and one with Shy-Drager syndrome. Significant decreases in cerebellin and CRH concentrations were found in the cerebellar hemisphere of these diseases compared with controls. These findings suggest important pathophysiological roles of cerebellin and CRH in these cerebellar diseases. Such significant decreases were not found in neuropeptide Y and somatostatin.
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PMID:Decrease in cerebellin and corticotropin-releasing hormone in the cerebellum of olivopontocerebellar atrophy and Shy-Drager syndrome. 758 64

We report an immunohistochemical investigation of the striatal efferents in the striatum, globus pallidus, and substantia nigra of five patients with multiple system atrophy (MSA): olivopontocerebellar atrophy (2), striatonigral degeneration (2), and Shy-Drager syndrome (1). All patients manifested parkinsonism during the clinical course of their illness. The administration of levodopa improved the symptoms of two patients, but not of the other three. Brain tissues from five age-matched neurologically normal subjects served as controls. Immunohistochemical assays were carried with antibodies against met-enkephalin, substance P, and calbindin-D28k. Irrespective of the clinical form of multiple system atrophy, the immunoreactivity with the antibodies was reduced at the dorsolateral portion of the striatum and the ventrolateral portions of the globus pallidus and of the substantia nigra. The woolly fiber arrangement of reaction product deposits seen in both segments of the globus pallidus of normal individuals was totally absent in the ventrolateral portions of the three patients who did not have a response to levodopa. By contrast, there were positively stained woolly fibers in globus pallidum segments of the two levodopa-responsive patients, even though their number and size were decreased in comparison with controls. These results indicate that the three clinical forms of multiple system atrophy share common topographic alterations of the striatal efferent system and that the severity of the involvement correlates with the clinically observed effect of levodopa on the parkinsonism.
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PMID:Striatal efferent involvement and its correlation to levodopa efficacy in patients with multiple system atrophy. 890 45

Alkaline sphingomyelinase (alk-SMase) is a new member of the NPP (nucleotide pyrophosphatase/phosphodiesterase) family that hydrolyses SM (sphingomyelin) to generate ceramide in the intestinal tract. The enzyme may protect the intestinal mucosa from inflammation and tumorigenesis. PAF (platelet-activating factor) is a pro-inflammatory phospholipid involved in pathogenesis of inflammatory bowel diseases. We examined whether alk-SMase can hydrolyse and inactivate PAF. [3H]Octadecyl-labelled PAF was incubated with purified rat intestinal alk-SMase or recombinant human alk-SMase expressed in COS-7 cells. The hydrolytic products were assayed with TLC and MS. We found that alkSMase cleaved the phosphocholine head group from PAF and generated 1-O-alkyl-2-acetyl-sn-glycerol. Differing from the activity against SM, the activity against PAF was optimal at pH 7.5, inhibited by EDTA and stimulated by 0.1-0.25 mM Zn2+. The activity was abolished by site mutation of the predicted metal-binding sites that are conserved in all NPP members. Similar to the activity against SM, the activity against PAF was dependent on bile salt, particularly taurocholate and taurochenodeoxycholate. The V(max) for PAF hydrolysis was 374 mumol x h(-1) x (mg of protein)(-1). The hydrolysis of PAF and SM could be inhibited by the presence of SM and PAF respectively, the inhibition of PAF hydrolysis by SM being stronger. The PAF-induced MAPK (mitogen-activated protein kinase) activation and IL-8 (interleukin 8) release in HT-29 cells, and chemotaxis in leucocytes were abolished by alk-SMase treatment. In conclusion, alk-SMase hydrolyses and inactivates PAF by a phospholipase C activity. The finding reveals a novel function, by which alk-SMase may counteract the development of intestinal inflammation and colon cancer.
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PMID:Intestinal alkaline sphingomyelinase hydrolyses and inactivates platelet-activating factor by a phospholipase C activity. 1625 17