Small constrained SP1–7 analogs bind to a unique site and promote anti-allodynic effects following systemic injection in mice. (9th July 2015)

• Record Type: Journal Article
• Authors: Jonsson, A.; Fransson, R.; Haramaki, Y.; Skogh, A.; Brolin, E.; Watanabe, H.; Nordvall, G.; Hallberg, M.; Sandström, A.; Nyberg, F.
• Is Part Of: Neuroscience. Volume 298(2015)
• Page Start: 112
• Page End: 119
• Publication Date: 2015-07-09
• Subjects: ANOVA analysis of variance -- EM-2 endomorphin-2 -- i.p. intraperitoneal -- NK1 neurokinin-1 -- SCI spinal cord injury -- SNI spared nerve injury -- SP substance P; anti-allodynia -- peptidomimetics -- receptor screening -- spared nerve injury -- substance P (SP) -- SP1–7; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2015.04.002
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: The neuropeptide SP1–7 attenuates signs of allodynia in the SNI mouse model. One low molecular weight SP1–7 analog exhibits an anti-allodynic activity. An extensive target screen did not reveal the binding site of SP1–7 . Abstract: Previous results have shown that the substance P (SP) N-terminal fragment SP1–7 may attenuate hyperalgesia and produce anti-allodynia in animals using various experimental models for neuropathic pain. The heptapeptide was found to induce its effects through binding to and activating specific sites apart from any known neurokinin or opioid receptor. Furthermore, we have applied a medicinal chemistry program to develop lead compounds mimicking the effect of SP1–7 . The present study was designed to evaluate the pharmacological effect of these compounds using the mouse spared nerve injury (SNI) model of chronic neuropathic pain. Also, as no comprehensive screen with the aim to identify the SP1–7 target has yet been performed we screened our lead compound H-Phe-Phe-NH2 toward a panel of drug targets. The extensive target screen, including 111 targets, did not reveal any hit for the binding site among a number of known receptors or enzymes involved in pain modulation. Our animal studies confirmed that SP1–7, but also synthetic analogs thereof, possesses anti-allodynic effects in the mouse SNI model of neuropathic pain. One of the lead compounds, a constrained H-Phe-Phe-NH2 analog, was shown to exhibit a significant anti-allodynic effect.