An ex vivo study on immunohistochemical localization of MMP-7 and MMP-9 in temporomandibular joint discs with internal derangement

Abstract

Internal derangement (ID) is among the most common disorders of the temporomandibular joint (TMJ). Previous research by our group highlighted a correlation between apoptosis and TMJ ID. Metalloproteinases (MMP)-7 and -9 have been shown to play an important role in extracellular matrix ECM) homeostasis and, through it, in joint disc remodelling. The immunohistochemical expression of MMP-7 and -9 was investigated in discs from patients with TMJ ID and from healthy donors and compared with the degree of histological tissue degeneration. The collagen fibre arrangement in pathological discs exhibited varying degrees of disruption. New vessels were consistently detected; endothelial cells from these vessels were immunolabelled with both MMP-7 and MMP-9. More or less intense MMP-7 and MMP-9 immunolabelling was detected in the cytoplasm of disc cells from all patients. MMP-7 and MMP-9 immunostaining was significantly different between pathological and normal discs and correlated with the extent of histopathological degeneration. MMP-7 and MMP-9 upregulation in discs from patients with TMJ ID demonstrates their involvement in disc damage in this disorder. A greater understanding of these processes could help identify ways to curb MMP overproduction without affecting their tissue remodelling action. The design of specific inhibitors for these MMPs would not only help to gain insights into the biological roles of MMPs, but would also aid in developing therapeutic interventions for diseases associated with abnormal ECM degradation.

Interleukin-6 expression in disc derangement of human temporomandibular joint and association with osteoarthrosis

“…For the past few years, many papers have been published showing the participation of various markers and distinct pathways in the progression of TMJ ID using TMJ discs and synovial fluid (Kubota et al, 1998, De Alcantara Camejo et al, 2014, Loreto et al, 2013, Wake et al, 2013, Kim et al, 2012, Leonardi et al, 2010a, Vernal et al, 2008, Sato et al, 2003. Sato et al, in 2003, performed a study using also an immuno-histochemical technique for the examination of synovial tissue from 46 temporomandibular joints with internal derangement in 44 patients.…”

“…Inflammatory changes in the TMJ modify physical and functional properties, first reversibly and finally irreversibly, reducing its ability to withstand pressure and compression forces (Israel et al, 1991). Loreto et al (2013). showed that MMP-7 and MMP-9 are expressed in arthritic joints, and provided evidence of a role for those MMPs in disc damage in TMJ ID, with higher expression detected in the posterior band rather than in the anterior and intermediate bands of ADDwR and ADDwoR discs.…”

“…Since the inflammatory process influences the progression of ID, this study was designed to test the hypothesis that IL-6 may be more highly expressed in the TMJ disc in cases of ADDwR and ADDwoR, and not only in the synovial fluid, as already extensively described in the literature (De Alcantara Camejo et al, 2014, Loreto et al, 2013, Kim et al, 2012, Sato et al, 2003.…”

Role of matrix metalloproteinases in dental caries, pulp and periapical inflammation: An overview

“…caries lesion), 23 even though the level of TIMPs found in active carious lesions is insufficient to block the progression of dental hard tissue destruction mediated by MMPs. 24 Cysteine cathepsin found in dentine has the ability to activate latent MMPs. 25 The cathepsin activity increases with increasing depth of lesion.…”

N-cadherin has a protective role in stable human atherosclerotic plaques: a morphological and immunohistochemical study

“…For immunohistochemical analysis, specimens were processed as previously described [26]. Briefly, the slides were dewaxed in xylene, hydrated using graded ethanols and were incubated for 30 min in 0.3% H 2 O 2 /methanol to quench endogenous peroxidase activity and then rinsed for 20 min with phosphate- Xels of the analyzed fields.…”