The analgesic activity of novel synthesized tetrapeptides: overview

Abstract

The tetrapeptide class of biased analgesics from an Australian fungus targets the -opioid receptor. The current study sought to investigate the analgesic and anti-inflammatory effects of Tyr-MIF-1 mimetics in rats suffering from acute pain. We report the synthesis of two new compounds which are hybrid molecules between the substituted pyrrole (Pyr) and analogues of Tyr MIF-1 peptide. The in vitro opioid activity of the analogs was tested in the guinea pig ileum (GPI) and naloxone-induced pain model. The study examined the effect of an analog to an N-terminal nociceptin fragment on the behavior of albino rats. We have also elucidated a novel G protein-biased agonist, Phe-Phe-Asp]NH2, for the management of moderate to severe acute pain following abdominoplasty. The pharmacophore based on Phe, NH2, was synthesised and characterized by solid phase chemistry and high performance liquid chromatography/mass spectrometry (HPLC/MS). The results show that a series of hybrid molecules with a unique stereochemical arrangement of hydrophobic amino acids, bilaids A-C, were synthesized. The effects of a new molecule, an analog of N-Terminal Nociceptinal Fragment (PK20M), on motor and exploratory activity of mature rats and in 42-day pups and 21-day rat pups were evaluated. The antinociceptive and antipyretic activities of the original molecule were evaluated in a model of post-incisional pain in rats at doses lower than 1g/kg. The present study reporting the overview of analgesic activity of some novel synthesized tetrapeptides fragments shows satisfaction effects comparing with morphine, aspirin, naloxone, etc.