Gene/Protein Disease 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)

The neuropeptide substance P (SP), which has been suggested to mediate neurogenic inflammation, induces in human neutrophils the activation of the respiratory burst measured as O2 consumption and H2O2 production, and a cytochalasin B-dependent secretion of specific and azurophilic granules. The SP(4-11) fragment is much more stimulant than the entire molecule, whereas the SP(1-4) fragment is inactive. The respiratory and secretory response to SP are associated with an activation of phosphoinositide turnover, of Ca2+ influx and release from intracellular stores. Pertussis toxin inhibits 70% of the respiratory response and the residual 30% activity remains, even increasing 10-fold the concentration of the toxin. 1-(5-Isoquinolinesulfonyl)-2-methylpiperazine, a putative inhibitor of protein kinase C, does not modify the respiratory response to SP. Cytochalasin B significantly depresses the activation of the respiration by SP, whereas it moderately enhances the activation of phosphoinositide turnover and potentiates the increase of intracellular Ca2+ concentration. The results are discussed in relation to the receptor apparatus involved in SP activity, the signal transduction sequence activated by SP for the stimulation of NADPH oxidase, and the role of cell response to SP in the inflammatory process.
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PMID:Activation of human neutrophils by substance P. Effect on oxidative metabolism, exocytosis, cytosolic Ca2+ concentration and inositol phosphate formation. 245

1. The generation of superoxide anions (O2-) by intact pig coronary artery rings was measured using a lucigenin-enhanced chemiluminescence technique and a histochemical technique with Nitroblue Tetrazolium (NBT) staining. 2. Isolated arteries with intact endothelium generated O2- at a rate of 9.0 +/- 0.8 pmol min-1 (mg dry weight)-1; this rate was diminished by about 24% when the endothelium was removed. The NBT staining of arterial ring preparations showed formazan precipitation mainly in the intima. Arterial rings were pretreated with diethylthiocarbamate in order to inhibit Cu-Zn superoxide dismutase (SOD) activity which increased the O2- generation by 184 +/- 55% (n = 10; P < 0.01). Stimulation of protein kinase C with phorbol 12-myristate 13-acetate (5 microM) enhanced endothelium-dependent O2- generation by 136 +/- 20% (n = 19; P < 0.01). Neither stimulation with bradykinin or substance P, nor inhibition with NG-nitro-L-arginine methyl ester of endothelial nitric oxide synthase had a significant effect on O2- generation. In contrast, the inhibition of flavoproteins with diphenyliodonium decreased concentration-dependent O2- generation (IC50, 1.85 +/- 5.33 microM). Inhibition of tetrahydrobiopterin synthesis with 2,4-diamino-6-hydroxy-pyrimidine resulted in a reduced generation of O2- by about 55%. 3. The addition of 100 microM NADH and 100 microM NADPH resulted in an excessive generation of O2- at a rate of 0.68 +/- 0.03 and 0.26 +/- 0.01 nmol O2- min-1 (mg protein)-1, respectively, in the membrane fraction, but not in the cytosolic fraction, of homogenates obtained from arteries. 4. The results suggest that intact coronary arteries do generate O2- under basal conditions and that the endothelial layer significantly contributes to this phenomenon. This generation of O2- is greatly influenced by intrinsic SOD activity. It is suggested that basal vascular O2- generation is mainly due to membrane-bound NAD(P)H oxidase activity and/or tetrahydrobiopterin-dependent processes.
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PMID:Endothelial-derived superoxide anions in pig coronary arteries: evidence from lucigenin chemiluminescence and histochemical techniques. 914 21

Substance P (SP), a neurotransmitter of the central and peripheral nervous system, has been implicated as a mediator of the pulmonary inflammatory response through its stimulatory effects on neutrophils. We investigated the role of SP in priming the production of reactive oxygen species by human neutrophils with the cytochrome c reduction assay and by flow cytometry using the intracellular oxidizable probe dichlorofluorescein. We also investigated SP-induced formation of nitrite and nitrate as an index of nitric oxide (NO) production. Our results indicate that SP primes two distinct pathways with respect to the induction of reactive oxygen species in the human neutrophil: the production of superoxide anion and hydrogen peroxide by the calmodulin-dependent NADPH oxidase, and the generation of NO by a constitutive NO synthase. Preincubation of neutrophils with inhibitors of calmodulin and NO synthase diminished the oxidative response in an additive fashion. These results give insight into distinct signal transduction pathways in the SP-primed neutrophil with respect to the formation of superoxide anion, hydrogen peroxide, and NO.
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PMID:Substance P primes the formation of hydrogen peroxide and nitric oxide in human neutrophils. 1038 Sep 7

A common feature in asthma is the induction of reactive oxygen species (ROS) and the AP-1 transcription factor during the inflammatory process. AP-1 induction leads to an increased expression of pro-inflammatory cytokines. Also, higher levels of the pro-inflammatory neuropeptide substance P (SP) have been reported in bronchoalveolar-lavage fluid of asthmatics. Here, the role of SP on ROS induction and the downstream activation of AP-1 in A549 airway epithelial cells was investigated by dichloroflourescein-diacetate method and reporter gene assays. The SP-mediated AP-1 induction was dependent on extracellular calcium and ROS. The likely source of ROS are the mitochondria as rotenone inhibited AP-1 induction and the p47phox subunit of the NADPH oxidase complex, responsible for ROS generation in phagocytotic cells, was not expressed in A549 cells assayed by RT-PCR. This is consistent with results obtained from cells of murine bronchial epithelium, isolated by laser capture microdissection. In summary, this study provides evidence for an SP-mediated induction of AP-1, which may contribute to the expression of pro-inflammatory cytokines.
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PMID:Substance P mediates AP-1 induction in A549 cells via reactive oxygen species. 1554 46

The effects of dihydropyridine Ca2+ channel blockers (DHP) and ACE inhibitors on superoxide formation and nitric oxide (NO) bioavailability were compared in human EA.Hy926 endothelial cells (EC). EC were stimulated 4 h with angiotensin II (Ang II, 10 nM) +/- study drugs. Specific superoxide formation was measured by lucigenin-enhanced chemiluminescence, reduction of cytochrome c and rhodamine-123 fluorescence. Free NO release was determined with an amperometric NO sensor. NADPH oxidase subunits expression was examined with Western Blot. In untreated EC the intracellular superoxide is -64.3 +/- 6.0% decreased compared to Ang II stimulated EC. Elevated extracellular superoxide formation was on a -43.0 +/- 1.7% lower level in untreated EC. The DHP Ca2+-channel agonist BayK8644 and ACE inhibitors captopril and ramiprilat led extracellular superoxide concentration to control level. Enalaprilat blocked extracellular superoxide, the DHP amlodipine and nisoldipine prevented intracellular increases only (n = 8-9, p < 0.05). Icatibant (HOE 140), a kinin-B2 receptor antagonist, attenuated antioxidant actions of all tested agents except of nisoldipine. Ang II-induced superoxide was elevated by the phorbolester PMA and blocked by the protein kinase C (PKC) inhibitor chelerythrine. Suppression of substance P-evoked NO release by Ang II (>70%, n = 6) was reversed by the PKC inhibitor chelerythrine, the DHP amlodipine and nisoldipine and the ACE inhibitor ramiprilat. Further, Ang II reduces Nox-4 expression by 34.5 +/- 4.9. Nox-2 expression was not regulated. DHP and ACE inhibitors exert different antioxidant effects in human EC stimulated with Ang II, but both improve NO bioavailability via bradykinin and modulation of redox-regulating enzymes.
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PMID:Antioxidant and nitric oxide-sparing actions of dihydropyridines and ACE inhibitors differ in human endothelial cells. 1622 25

Unregulated microglial activation has been implicated as a pivotal factor contributing to Parkinson's disease. Using mesencephalic neuron-glia cultures, we address the novel possibility that peptides endogenous to the substantia nigra (SN), substance P and dynorphin (10(-13)-10(-14) M), are opposing mediators of microglial activation and consequent DA neurotoxicity. Here, we identify that substance P (10(-13)-10(-14) M) is selectively toxic to DA neurons in a microglia-dependent manner. Mechanistically, substance P (10(-13)-10(-14) M) activated microglial NADPH oxidase to produce extracellular superoxide and intracellular reactive oxygen species (ROS). Neuron-glia cultures from mice lacking a functional NADPH oxidase complex (PHOX-/-) were insensitive to substance P (10(-13)-10(-14) M) -induced loss of DA neuron function. Mixed glia cultures from (PHOX-/-) mice failed to show a significant increase in intracellular ROS in response to substance P compared with control cultures (PHOX+/+). Further, dynorphin (10(-14) M) inhibited substance P (10(-13) M) -induced loss of [3H] DA uptake. Here we demonstrate a tightly regulated mechanism governing microglia-derived oxidative stress, where the neuropeptide balance of dynorphin and substance P is critical to DA neuron survival.
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PMID:Potent regulation of microglia-derived oxidative stress and dopaminergic neuron survival: substance P vs. dynorphin. 1644 97

Mast cells' hyperplasia and activation are prominent features in Trichinella spiralis infection. Recently, it was shown that TSL-1 antigens from T. spiralis muscle larvae induce IL-4 and TNF release by unsensitized, normal mast cells (MC) involving an Ig-independent mechanism. In this study, we characterized histamine secretion induced by TSL-1 antigens from normal, unsensitized rat peritoneal MC. Maximum histamine secretion (30+/-5.3% SEM, n=13) was achieved with 30 ng/mL TSL-1 antigens. However, TSL-1 did not induce an increase in beta-hexosaminidase release or NADPH oxidase activity by MC. Interestingly, histamine secretion by TSL-1 was completed at 10s, and was inhibited by both Bordetella pertussis toxin and neuraminidase V, characteristics similar to those involved in substance P-induced histamine secretion. However, in contrast to substance P, TSL-1 induced histamine secretion in the absence of detectable changes in intracellular Ca(2+). We are investigating the molecular pathways involved in MC activation by TSL-1.
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PMID:Trichinella spiralis: histamine secretion induced by TSL-1 antigens from unsensitized mast cells. 1660 Feb 18

Substance P (SP) via neurokinin type 1 receptor activates leukocytes to produce burst release of reactive oxygen species (ROS) and increases leukocytes adhesion to the vessels in the inflamed bladder. Activation of neutrophil nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity may contribute to the neutrophil ROS production. We explored the therapeutic effect of traditional Chinese formula for urinary dysfunction, Wu Lin San (WLS), and a modified formula WLS plus Shan Zha (WLSSZ) on SP-induced bladder hyperactivity. We evaluated WLS, Shan Zha, and WLSSZ effect on neutrophils NADPH oxidase activity in SP-stimulated neutrophils in vitro, and isovolumetric cystometrogram and ROS activity in vivo in anesthetized rat bladder with SP stimulation. Our results showed that WLS, Shan Zha, and WLSSZ inhibited SP-induced NADPH oxidase activity in an order WLSSZ>Shan Zha>WLS. Exogenous SP enhanced systemic vasodilation, bladder hyperactivity and bladder ROS. One week of oral administration of WLS or WLSSZ significantly reduced SP-induced bladder ROS amount and leukocyte accumulation and ameliorated the hyperactive bladder response. The therapeutic action was better in WLSSZ than in WLS. Our results indicate that a modified formula Wu Lin San plus Shan Zha can potentially ameliorate SP-induced neurogenic inflammation possibly via the inhibition of leukocyte NADPH oxidase activity.
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PMID:Combination of Wu Lin San and Shan Zha ameliorates substance P-induced hyperactive bladder via the inhibition of neutrophil NADPH oxidase activity. 1663 95

Oxidative stress has been implicated in intra-abdominal adhesion formation. Substance P, a neurokinin-1 receptor (NK-1R) ligand, facilitates leukocyte recruitment and reactive oxygen species (ROS) generation. We have shown in a rat model of adhesion formation that intraperitoneal administration of a NK-1R antagonist at the time of abdominal operation reduces postoperative adhesion formation. Thus we determined the effects of NK-1R antagonist administration on peritoneal leukocyte recruitment and oxidative stress within 24 h of surgery. Adhesions were induced in Wistar rats randomly assigned to receive the antagonist or vehicle intraperitoneally. Peritoneal tissue was isolated at 2, 4, 6, and 24 h after surgery for analysis of the oxidative stress biomarkers 8-isoprostane (8-IP), protein carbonyl, NADPH oxidase, myeloperoxidase (MPO), and ICAM-1 and VCAM-1 mRNAs. Total antioxidant capacity of peritoneal fluid was also determined. MPO, NADPH oxidase, 8-IP, and protein carbonyl were elevated (P < 0.05) by 6 h. ICAM-1 mRNA was elevated (P < 0.05) by 2 h, whereas VCAM-1 levels decreased (P < 0.05) at 24 h. The NK-1R antagonist delayed the MPO rise and reduced (P < 0.05) 8-IP levels by 6 h and ICAM-1 mRNA, VCAM-1 mRNA, and protein carbonyl at 2 h. The antagonist also increased (P < 0.05) the antioxidant capacity of peritoneal fluid at all time points. These data further support a role for oxidative stress in adhesion formation and suggest that the NK-1R antagonist may limit adhesions, in part, by reducing postoperative oxidative stress through an inhibition of neutrophil recruitment and an increase in peritoneal fluid antioxidant capacity.
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PMID:A neurokinin-1 receptor antagonist that reduces intra-abdominal adhesion formation decreases oxidative stress in the peritoneum. 1762 72

Although dysregulated substance P (SP) has been implicated in the pathophysiology of Parkinson's disease (PD), how SP affects the survival of dopaminergic neurons remains unclear. Here, we found that mice lacking endogenous SP (TAC1(-/-)), but not those deficient in the SP receptor (neurokinin-1 receptor, NK1R), were more resistant to lipopolysaccharide (LPS)- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced nigral dopaminergic neurodegeneration than wild-type controls, suggesting a NK1R-independent toxic action of SP. In vitro dose-response studies revealed that exogenous SP enhanced LPS- and 1-methyl-4-phenylpyridinium (MPP(+))-induced dopaminergic neurodegeneration in a bimodal manner, peaking at submicromolar and subpicomolar concentrations, but was substantially less effective at intermediate concentrations. Mechanistically, the actions of submicromolar levels of SP were NK1R-dependent, whereas subpicomolar SP-elicited actions required microglial NADPH oxidase (NOX2), the key superoxide-producing enzyme, but not NK1R. Subpicomolar concentrations of SP activated NOX2 by binding to the catalytic subunit gp91(phox) and inducing membrane translocation of the cytosolic subunits p47(phox) and p67(phox). The importance of NOX2 was further corroborated by showing that inhibition or disruption of NOX2 blocked subpicomolar SP-exacerbated neurotoxicity. Together, our findings revealed a critical role of microglial NOX2 in mediating the neuroinflammatory and dopaminergic neurodegenerative effects of SP, which may provide new insights into the pathogenesis of PD.
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PMID:Substance P exacerbates dopaminergic neurodegeneration through neurokinin-1 receptor-independent activation of microglial NADPH oxidase. 2520 87


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