Expression of MMP-2 and MMP-9 in the rat trigeminal ganglion during the development of temporomandibular joint inflammation

Author(s)

G.C. Nascimento ^[1] ; E. Rizzi ^[2] ; R.F. Gerlach ^[3] ; C.R.A. Leite-Panissi ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Programa Posgrad Psicobiol, Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Farmacol, Ribeirao Preto, SP - Brazil

^[3] Univ Sao Paulo, Fac Odontol Ribeirao Preto, Dept Morfol Fisiol Patol Basica, Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Brazilian Journal of Medical and Biological Research; v. 46, n. 11, p. 956-967, 2013-11-18.

Abstract

Orofacial pain is a prevalent symptom in modern society. Some musculoskeletal orofacial pain is caused by temporomandibular disorders (TMDs). This condition has a multi-factorial etiology, including emotional factors and alteration of the masticator muscle and temporomandibular joints (TMJs). TMJ inflammation is considered to be a cause of pain in patients with TMD. Extracellular proteolytic enzymes, specifically the matrix metalloproteinases (MMPs), have been shown to modulate inflammation and pain. The purpose of this investigation was to determine whether the expression and level of gelatinolytic activity of MMP-2 and MMP-9 in the trigeminal ganglion are altered during different stages of temporomandibular inflammation, as determined by gelatin zymography. This study also evaluated whether mechanical allodynia and orofacial hyperalgesia, induced by the injection of complete Freund's adjuvant into the TMJ capsule, were altered by an MMP inhibitor (doxycycline, DOX). TMJ inflammation was measured by plasma extravasation in the periarticular tissue (Evans blue test) and infiltration of polymorphonuclear neutrophils into the synovial fluid (myeloperoxidase enzyme quantification). MMP expression in the trigeminal ganglion was shown to vary during the phases of the inflammatory process. MMP-9 regulated the early phase and MMP-2 participated in the late phase of this process. Furthermore, increases in plasma extravasation in periarticular tissue and myeloperoxidase activity in the joint tissue, which occurred throughout the inflammation process, were diminished by treatment with DOX, a nonspecific MMP inhibitor. Additionally, the increases of mechanical allodynia and orofacial hyperalgesia were attenuated by the same treatment. (AU)

• FAPESP's process: 11/10336-0 - Effects of MMP-2 recombinant in atherosclerotic vessels in vitro and evaluation of morphology, function and spread potential to other organs
• Grantee: João Paulo Mardegan Issa
• Support Opportunities: Regular Research Grants
• FAPESP's process: 09/04430-4 - Characterization of gelatinases in trigeminal ganglion during chronic inflammation in temporomandibular joint of rats
• Grantee: Glauce Crivelaro Do Nascimento
• Support Opportunities: Scholarships in Brazil - Master