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)

Mice infected with the protozoan parasite Trypanosoma brucei brucei and treated subcuratively with the trypanocidal drug diminazene aceturate develop an acute inflammatory meningoencephalitis with associated astrocytic proliferation. This reaction is very similar to that seen in the fatal posttreatment reactive encephalopathies that can occur in human African trypanosomiasis. The 11-amino acid neuropeptide substance P (SP) has recently been identified as a mediator in many inflammatory responses, and the development of potent, highly specific, nonpeptide SP antagonists has provided a new opportunity to investigate the possible involvement of SP in a variety of pathological conditions. We therefore postulated that SP may play a role in the development of the posttreatment inflammatory encephalopathy found in this experimental mouse model of African trypanosomiasis. In the present study RP-67,580, a SP antagonist that binds specifically to NK-1 receptors, was given intraperitoneally at a dose of 2 mg/kg twice daily to mice in which a severe meningoencephalitis had been produced. A significant reduction in both the severity of the inflammatory response (P = 0.0001) as well as the degree of astrocyte activation (P < 0.001) was found in the brains of these animals as compared with control mice that had not received RP-67,580. An inactive enantiomer of this SP antagonist, RP-68,651, had no effect on the central nervous system inflammatory reaction. We conclude from these findings that the neuropeptide SP plays a key role in the development of the severe central nervous system inflammatory response associated with African trypanosomiasis.
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PMID:A substance P antagonist, RP-67,580, ameliorates a mouse meningoencephalitic response to Trypanosoma brucei brucei. 910 23

Human African trypanosomiasis, also known as sleeping sickness, affects the CNS at the late stage of the disease. Untreated the disease is invariably fatal, and melarsoprol, the only available and effective treatment for CNS disease, is associated in up to 10% of cases with a severe post-treatment reactive encephalopathy (PTRE), which can itself cause death. We used a reproducible mouse model of the PTRE to investigate the pathogenesis and treatment of this condition. Mice infected with Trypanosoma brucei brucei and treated subcuratively with diminazene aceturate develop a severe meningoencephalitis that closely resembles PTRE. We previously reported that substance P plays an important role in PTRE. We investigated the effect of disrupting the gene encoding for the NK1 receptor in mice on the clinical and neuroinflammatory response in this model. After induction of PTRE, NK1-/- mice showed a significant reduction in clinical impairment compared with NK1+/+ mice, but the severity of the neuroinflammatory response was significantly greater in NK1-/- mice. To explore the mechanisms of this dissociated phenotype, we treated infected NK1-/- mice with antagonists to NK2 and NK3 receptors, either singly or in combination. While none of these antagonist treatments altered the clinical score, combined treatment with the NK2 and NK3 antagonists significantly reduced the neuroinflammatory grading score in the NK1-/- mice. Thus, the clinical and neuroinflammatory responses to parasite invasion can be mediated by different pathways, and, importantly, the neuroinflammatory response is altered by alternative tachykinin receptor usage. These findings could be exploited to develop novel anti-inflammatory therapies in Human African trypanosomiasis by modulating the NK1 receptor as well as the parasite.
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PMID:Clinical and neuroinflammatory responses to meningoencephalitis in substance P receptor knockout mice. 1280 19