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Symptom
Drug
Enzyme
Compound
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Query: UNIPROT:P20366 (
substance P
)
21,176
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
An endo-acting proline-specific oligopeptidase (
prolyl oligopeptidase
[POPase], EC 3.4.21.26) was purified to homogeneity from the Triton X-100 extracts of cells of Treponema denticola ATCC 35405 (a human oral spirochete) by a procedure that comprised five successive fast protein liquid chromatography steps. The POPase is a cell-associated 75- to 77-kDa protein with an isoelectric point of ca. 6.5. The enzyme hydrolyzed (optimum pH 6.5) the Pro-pNA bond in carbobenzoxy-Gly-Pro-p-nitroanilide (Z-Gly-Pro-pNA) and bonds at the carboxyl side of proline in several human bioactive peptides, such as bradykinin,
substance P
, neurotensin, angiotensins, oxytocin, vasopressin, and human endothelin fragment 22-38. The minimum hydrolyzable peptide size was tetrapeptide P3P2P1P'1, while the maximum substrate size was ca. 3 kDa. An imino acid residue in position P1 was absolutely necessary. The hydrolysis of Z-Gly-Pro-pNA was potently inhibited by the following, with the Ki(app) (in micromolar) in parentheses: insulin B-chain (0.7), human endothelin-1 (0.5), neuropeptide Y (1.7),
substance P
(32.0), T-kinin (4.0), neurotensin (5.0), and bradykinin (16.0). Chemical modification and inhibition studies suggest that the POPase is a serine endopeptidase whose activity depends on the catalytic triad of COOH ... Ser ... His but not on a metal. The amino acid sequence around the putative active-site serine is Gly-Gly-Ser-Asn-Pro-Gly. The enzyme is suggested to contain a reactive cysteinyl residue near the active site. Amino acid residues 4 to 24 of the first 24 N-terminal residues showed a homology of 71% with the POPase precursor from Flavobacterium meningosepticum and considerable homology with the Aeromonas hydrophila POPase. The ready hydrolysis of human bioactive peptides at bonds involving an imino acid residue suggests that enzymes like POPase may contribute to the chronicity of periodontal infections by participating in the peptidolytic processing of those peptides.
...
PMID:An endo-acting proline-specific oligopeptidase from Treponema denticola ATCC 35405: evidence of hydrolysis of human bioactive peptides. 752 1
The ability of washed whole cells of Treponema denticola ATCC 35405 to hydrolyze (inactivate)
substance P
, bradykinin, and angiotensin I was studied.
Substance P
was attacked primarily at the Phe-8-Gly-9 bond by a chymotrypsin-like proteinase (CTLP), at Pro-4-Gln-5 by an endo-acting
prolyl oligopeptidase
(POPase), and at Gln-5-Gln-6 by an endopeptidase (FALGPA-peptidase). Bradykinin was cleaved at Phe-5-Ser-6 by the FALGPA-peptidase and at Pro-7-Phe-8 by the POPase. Angiotensin I was rapidly converted to angiotensin II by the CTLP, and both angiotensin I and angiotensin II were further hydrolyzed at Pro-7-Phe-8 by the POPase. All these enzymes were assumed to be cell associated and were easily extracted with a mild (0.05 to 0.1%) Triton X-100 treatment. Because it was conceivable that the hydrolysis of
substance P
at the Phe-8-Gly-9 bond was catalyzed by a CTLP described earlier (V.-J. Uitto, D. Grenier, E. C. S. Chan, and B. C. McBride, Infect. Immun. 56:2717-2722, 1988), the enzyme was purified to homogeneity by means of conventional fast protein liquid chromatography procedures. For kinetic studies, Phe-8(4-nitro)-
substance P
(NSP) (absorption maximum at 309.2 nm, epsilon = 545 M-1 cm-1) was synthesized to replace
substance P
as a substrate in kinetic studies. In reversed-phase chromatography, both NSP and
substance P
gave identical results with both whole cells and the purified enzyme. The CTLP has a mass of 95 kDa, and its activity is suggested to be based on an active seryl residue, on an active imidazole group, and on an active carboxyl group but not on metal cations. The enzyme hydrolyzes N-succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroaniline (SAAPFNA, a typical chymotrypsin substrate) at a high rate and several proteins, such as calf thymus histone, human plasma fibrinogen, milk caseins, and gelatin. Among the substrates tested,
substance P
showed the highest affinity (Km = 0.22 mM) for the purified enzyme. Depending on conditions, clinically applicable chlorhexidine levels (3.2 mmol/liter, or 0.2%) strongly activated (up to fourfold) the hydrolysis of SAAPFNA by whole cells and the purified CTLP. The hydrolysis of NSP by whole cells and purified CTLP was slightly inhibited by chlorhexidine. The results demonstrated the versatility and the effectiveness of the outer membrane of T. denticola in occasioning a rapid breakdown and inactivation of human bioactive peptides and other peptidolytic catalyses.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Role of the chymotrypsin-like membrane-associated proteinase from Treponema denticola ATCC 35405 in inactivation of bioactive peptides. 754 86
Vildagliptin (NVP-LAF237/(2S)-{[(3-hydroxyadamantan-1-yl)amino]acetyl}-pyrrolidine-2-carbonitrile) was described as a potent, selective and orally bio-available dipeptidyl-peptidase IV (DPP IV, EC 3.4.14.5) inhibitor [Villhauer EB, Brinkman JA, Naderi GB, Burkey BF, Dunning BE, Prasad K, et al.1-[[(3-Hydroxy-1-adamantyl)amino]acetyl]-2-cyano-(S)-pyrrolidine: a potent, selective, and orally bioavailable dipeptidyl peptidase IV inhibitor with antihyperglycemic properties. J Med Chem 2003;46:2774-89]. Phase III clinical trials for the use of this compound in the treatment of Type 2 diabetes were started in the first quarter of 2004. In this paper, we report on (1) the kinetics of binding, (2) the type of inhibition, (3) the selectivity with respect to other peptidases, and (4) the inhibitory potency on the DPP IV catalyzed degradation of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and
substance P
. Vildagliptin behaved as a slow-binding DPP IV inhibitor with an association rate constant of 1.4x10(5)M(-1)s(-1) and a K(i) of 17nM. It is a micromolar inhibitor for dipeptidyl-peptidase 8 and does not significantly inhibit dipeptidyl-peptidase II (EC 3.4.11.2),
prolyl oligopeptidase
(EC 3.4.21.26), aminopeptidase P (EC 3.4.11.9) or aminopeptidase M (EC 3.4.11.2). There was no evidence for substrate specific inhibition of DPP IV by Vildagliptin or for important allosteric factors affecting the inhibition constant in presence of GIP and GLP-1.
...
PMID:Inhibition of dipeptidyl-peptidase IV catalyzed peptide truncation by Vildagliptin ((2S)-{[(3-hydroxyadamantan-1-yl)amino]acetyl}-pyrrolidine-2-carbonitrile). 1590 7
Prolyl oligopeptidase
(
POP
) is a serine peptidase which digests small peptide-like hormones, neuroactive peptides, and various cellular factors. Therefore, this peptidase has been implicated in many physiological processes as well as in some psychiatric disorders, most probably through interference in inositol cycle. Intense research has been performed to elucidate, on the one hand, the basic structure, ligand binding, and kinetic properties of
POP
, and on the other, the pharmacology of its inhibitors. There is fairly strong evidence of in vivo importance of
POP
on
substance P
, arginine vasopressin, thyroliberin and gonadoliberin metabolism. However, information about the biological relevance of
POP
is not yet conclusive. Evidence regarding the physiological role of
POP
is lacking, which is surprising considering that peptidase inhibitors have been exploited for drug development, some of which are currently in clinical trials as memory enhancers for the aged and in a variety of neurological disorders. Here we review the recent progress on
POP
research and evaluate the relevance of the peptidase in the metabolism of various neuropeptides. The recognition of novel forms and relatives of
POP
may improve our understanding of how this family of proteins functions in normal and in neuropathological conditions.
...
PMID:On the role of prolyl oligopeptidase in health and disease. 1719 52
The effects of a novel
prolyl oligopeptidase
(
POP
) inhibitor KYP-2047 on spatial memory of young (3-month-old) and old (8- to 9-month-old) scopolamine-treated rats (0.4 mg/kg intraperitoneally) was investigated in the Morris water maze. In addition, the concentrations of promnesic neuropeptide substrates of
POP
,
substance P
and neurotensin in various brain areas after acute and chronic
POP
inhibition were measured in young rats. In addition, inositol-1,4,5-trisphosphate (IP(3)) levels were assayed in rat cortex and hippocampus after effective 2.5-day
POP
inhibition. KYP-2047 (1 or 5 mg/kg 30 min. before daily testing) dose-dependently improved the escape performance (i.e. latency to find the hidden platform and swimming path length) of the young but not the old rats in the water maze.
POP
inhibition had no consistent effect on
substance P
levels in cortex, hippocampus or hypothalamus, and only a modest increase in neurotensin concentration was observed in the hypothalamus after a single dose of KYP-2047. Moreover, IP(3) concentrations remained unaffected in cortex and hippocampus after
POP
inhibition. In conclusion, the behavioural data support the earlier findings of the promnesic action of
POP
inhibitors, but the mechanism of the memory-enhancing action remains unclear.
...
PMID:Beneficial effect of prolyl oligopeptidase inhibition on spatial memory in young but not in old scopolamine-treated rats. 1724 63
Analysis of the effects of cyclosporine A (25-28 mgkg(-1)) and/or methotrexate (0.1 mgkg(-1)) treatments on dipeptidyl peptidase IV (DPPIV) and
prolyl oligopeptidase
(
POP
) activities and on algesic response in two distinct status of murine macrophages (Mphis) was undertaken. In resident Mphis, DPPIV and
POP
were affected by neither individual nor combined treatments. In thioglycolate-elicited Mphis, methotrexate increased DPPIV (99-110%) and
POP
(60%), while cyclosporine inhibited
POP
(21%). Combined treatment with both drugs promoted a rise (51-84%) of both enzyme activities. Only cyclosporine decreased (42%) the tolerance to algesic stimulus. Methotrexate was revealed to exert prevalent action over that of cyclosporine on proinflammatory Mphi
POP
. The opposite effects of methotrexate and cyclosporine on
POP
activity might influence the availability of the nociceptive mediators bradykinin and
substance P
in proinflammatory Mphis. The exacerbated response to thermally induced algesia observed in cyclosporine-treated animals could be related to upregulation of those mediators.
...
PMID:Methotrexate and cyclosporine treatments modify the activities of dipeptidyl peptidase IV and prolyl oligopeptidase in murine macrophages. 1835 29
Prolyl oligopeptidase
(
POP
) is a serine endopeptidase which hydrolyzes proline-containing peptides shorter than 30 amino acids. It has been suggested that
POP
is associated with cognitive functions, possibly via the cleavage of neuropeptides such as
substance P
(SP). Recently, several studies have also linked
POP
to the inositol 1,4,5-triphosphate (IP(3)) signaling. However, the neuroanatomical interactions between these substances are not known. We used double-labeled immunofluorescence to determine the
POP
colocalization with SP, SP receptor (neurokinin-1 receptor, NK-1R) and IP(3) type 1 receptor (IP(3)R1) in the rat brain. Furthermore, since striatal and cortical GABAergic neurons are involved in SP neurotransmission, we studied the coexpression of
POP
, SP and GABA by triple-labeled immunofluorescence.
POP
was moderately present in IP(3)R1-containing cells in cortex; the colocalization was particularly high in the thalamus, hippocampal CA1 field and cerebellar Purkinje cells. Colocalization of
POP
with SP and NK1-receptor was infrequent throughout the brain, though some
POP
and SP coexpression was observed in cerebellar Purkinje cells. We also found that
POP
partially colocalized with SP-containing GABAergic neurons in striatum and cortex. Our findings support the view that
POP
is at least spatially associated with the IP(3)-signaling in the thalamus, hippocampus and cerebellar Purkinje cells. This might point to a role for
POP
in the regulation of long-term potentiation and/or depression. Moreover, the low degree of colocalization of
POP
, SP and its NK-1R suggests that a transport system is needed either for
POP
or SP to make hydrolysis possible and that
POP
may act both intra- and extracellularly.
...
PMID:Spatial association of prolyl oligopeptidase, inositol 1,4,5-triphosphate type 1 receptor, substance P and its neurokinin-1 receptor in the rat brain: an immunohistochemical colocalization study. 1845 82
Prolyl oligopeptidase
(
POP
) is a serine protease that cleaves small peptides at the carboxyl side of an internal proline residue.
Substance P
, arginine-vasopressin, thyroliberin and gonadoliberin are proposed physiological substrates of this protease.
POP
has been implicated in a variety of brain processes, including learning, memory, and mood regulation, as well as in pathologies such as neurodegeneration, hypertension, and psychiatric disorders. Although
POP
has been considered to be a soluble cytoplasmic peptidase, significant levels of activity have been detected in membranes and in extracellular fluids such as serum, cerebrospinal fluid, seminal fluid, and urine, suggesting the existence of noncytoplasmic forms. Furthermore, a closely associated membrane prolyl endopeptidase (PE) activity has been previously detected in synaptosomes and shown to be different from the cytoplasmic
POP
activity. Here we isolated, purified and characterized this membrane-bound PE, herein referred to as mPOP. Although, when attached to membranes, mPOP presents certain features that distinguish it from the classical
POP
, our results indicate that this protein has the same amino acid sequence as
POP
except for the possible addition of a hydrophobic membrane anchor. The kinetic properties of detergent-soluble mPOP are fully comparable to those of
POP
; however, when attached to the membranes in its natural conformation, mPOP is significantly less active and, moreover, it migrates anomalously in SDS/PAGE. Our results are the first to show that membrane-bound and cytoplasmic
POP
are encoded by variants of the same gene.
...
PMID:Characterization of membrane-bound prolyl endopeptidase from brain. 1865 87
In vitro,
prolyl oligopeptidase
(
POP
) cleaves proline-containing bioactive peptides such as
substance P
, gonadotropin-releasing hormone, thyrotropin-releasing hormone, arginine-vasopressin, and neurotensin. Based on specific in vivo inhibition,
POP
has been suggested to be involved in cognitive and psychiatric processes but the identity of its physiological substrates has remained inconclusive. We have combined (a) sample snap-freezing and boiling buffer extraction, to limit protein degradation and reduce sample complexity; (b) pH two-dimensional liquid reverse-phase chromatography to enhance resolution; and (c) iTRAQ isobaric labeling to identify the rat brain peptides whose levels were differentially changed due to in vivo
POP
inhibition. In the hypothalamus, all the substrates found were part of precursors of secreted peptides such as copeptin, PACAP-related peptide, somatostatin, and proSAAS derived peptides, while in the cerebellum the peptides were derived from carcinoma-amplified sequence 1 homolog and calmodulin. In the striatum, somatostatin precursor derived peptide, fragments from E3-SUMO protein ligase RanBP2, and the subunit 5A of cytochrome c oxidase were increased. When analyzing the peptides that were significantly reduced by
POP
inhibition we found fragments from large protein complexes but, exclusively in the cerebellum, bioactive peptides such as cerebellin and fibrinopeptides A and B were detected.
...
PMID:Combination of snap freezing, differential pH two-dimensional reverse-phase high-performance liquid chromatography, and iTRAQ technology for the peptidomic analysis of the effect of prolyl oligopeptidase inhibition in the rat brain. 1953 95
Soluble forms of amyloid-beta (Abeta) have been considered responsible for cognitive dysfunction prior to senile plaque formation in Alzheimer's disease (AD). As its mechanism is not well understood, we examined the effects of repeated i.c.v. infusion of soluble Alphabeta(25-35) on peptidergic system and glial cells in the pathogenesis of AD. The present study aims to investigate the protective effects of memantine on Abeta(25-35)-induced changes in peptidergic and glial systems. Infusion of Alphabeta(25-35) decreased the level of immunoreactive somatostatin (SS) and
substance P
(SP) in the hippocampus prior to neuronal loss or caspase activation, which is correlated with the loss of spine density and activation of inducible nitric-oxide synthase (iNOS). Biochemical experiment with peptide-degrading enzymes,
prolyl oligopeptidase
(
POP
) and endopeptidase 24.15 (EP 24.15) activities demonstrated a concomitant increase with the activation of glial marker proteins, glial fibrillary acidic protein (GFAP) and CD11b in the Abeta-treated hippocampus. Double immunostaining experiments of EP 24.15 and GFAP/CD11b antibodies clearly demonstrated the co-localization of neuro peptidases with astrocytes and microglia. Treatment with memantine, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist significantly attenuated Abeta(25-35)-induced changes of neuropeptides, their metabolizing enzymes, glial marker proteins, and activation of iNOS. Taken together, the data implies that memantine exerts its protective effects by modulating the neuropeptide system as a consequence of suppressing the glial cells and oxidative stress in AD model rat brain regions.
...
PMID:Effects of memantine on soluble Alphabeta(25-35)-induced changes in peptidergic and glial cells in Alzheimer's disease model rat brain regions. 1973 35
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