Evaluation of anti-inflammatory and analgesic efficacy of poloxamer-prostaglandin J2 (PL-PGJ2) system application in rat temporomandibular joint

• Grant number: 11/19094-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2011
• End date: November 30, 2013
• Field of knowledge: Biological Sciences - Pharmacology - Biochemical and Molecular Pharmacology
• Principal Investigator: Juliana Trindade Clemente Napimoga
• Grantee: Henrique Ballassini Abdalla
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

Pain resulting from temporomandibular joint dysfunctions (TMD) is known to be caused by the release of inflammatory mediators and sympathomimetic amines leading to the sensitization of nociceptors and, consequently, to a phenomenon called hypernociception. Since pain is the primary complaint of patients with TMD and strategies for the control of pain related to the TMD are unsatisfactory, the development of more effective therapeutic approaches for pain control is of great interest to patients and clinicians. The potential use of nanotechnology to enhance micelle drug delivery system (MDDS) as well as the effectiveness and availability of drugs has been investigated. Among the constituents of the MDDS are the block copolymers of the poloxamer class (PL) and, in particular, the PL407, the latter of which is highly biocompatible and has been approved by the Food and Drug Administration for clinical use (e.g. poloxamers-PL). The activation of PPARg receptors in the temporomandibular joint (TMJ) by the 15d-PGJ2 synthetic agonist has been reported to induce anti-inflammatory and anti-nociceptive effects through the co-participation of peripheral receptors (k/d opioids) mediated by the activation of the intracellular pathway (L-arginine/NO/GMP/K+ ATP). Therefore, the aim of this study is to assess the anti-inflammatory and analgesic efficacy of the poloxamer-prostaglandin J2 (PL-PGJ2) injected in the TMJ. The animals will be pretreated with PL-PGJ2 and, subsequently, receive an intra-articular injection of formalin, an inflammatory agent. A behavioral analysis, an evaluation of the neutrophil migration, the formation of edema, the release of mediators (TNF-±, IL-1 ² and KC) and expression of adhesion molecules will be considered to assess the anti-inflammatory and analgesic effects. This proposed work is intended for helping develop a new therapy for patients with TMD.