Matrix metalloproteinase 2 activity decreases in human periodontal ligament fibroblast cultures submitted to simulated orthodontic force

Abstract

Orthodontic force compresses the periodontal ligament promoting the expression of pro-inflammatory mediators and matrix metalloproteinases responsible for tooth movement. The extent in time while periodontal cells are being treated and the increment in the amount of mechanical stress caused by the orthodontic force is thought to regulate the levels of metalloproteinases in the periodontal tissue. To study the possible regulation in the activity of metalloproteinases 2, 3, 7, 9, and 10 by simulated orthodontic force, human periodontal ligament fibroblast cultures were centrifuged (141 × g) for 30, 60, 90, and 120 min, simulating the orthodontic force. Cell viability, protein quantification, and activity of metalloproteinases by zymography were evaluated at 24, 48, and 72 h after centrifugation in both cell lysates and growth medium. The activity of the 72-kDa matrix metalloproteinase 2 was decreased at 24 h regardless of the duration of centrifugation and at 48 h in cells centrifuged for 30 min only. Decrease in the amount of total protein in lysates was seen at 48 and 72 h with no change in cell viability. The data seem to indicate that the amount of mechanical stress regulates the levels of secreted matrix metalloproteinase 2. In addition, the centrifugation as a model for simulated orthodontic force may be used as a simple and reliable method to study the role played by matrix metalloproteinases in periodontal ligament when submitted to mechanical force as occurring during tooth movement.

Fluid shear stress regulates metalloproteinase-1 and 2 in human periodontal ligament cells: Involvement of extracellular signal-regulated kinase (ERK) and P38 signaling pathways

“…Numerous studies have shown that tensile and compressive stresses induce the expression of MMPs and TIMPs at mRNA and protein levels in PDL cells (Bolcato-Bellemin et al, 2000;Huang et al, 2008;Kook et al, 2011;Lisboa et al, 2009;Ziegler et al, 2010). The expression patterns vary under different modes of mechanical strains.…”

Evaluation of the Human Amniotic Membrane as a Scaffold for Periodontal Ligament Fibroblast Attachment and Proliferation

“…The role of fibroblasts is not only to secrete the components of the extracellular matrix (ECM) such as collagen, fibronectin and proteoglycan (Graham et al 2008;Spinale 2007), but also to secrete ECM-degrading enzymes called matrix metalloproteases (MMPs) (Kukacka et al 2005;Lindner et al 2012). In the case of periodontal fibroblasts, it is known that they release MMP-2, 8 and 9 (Kim et al 2012;Lisboa et al 2009;Rai et al 2010). The MMPs may degrade the collagen of the membrane, resulting in a lack of attachment cues for the cells, thereby promoting cellular detachment and eventually, cellular death.…”

Zimography is an effective method for detection of matrix metalloproteinase 2 (MMP-2) activity in cultured human fibroblasts

“…A decrease of more than 20% on cell viability below control levels has been shown to interfere with the reliability of the data 1,11 . In our study, no significant difference was found on cell viability ratio between control and experimental groups.…”

“…The cells were stimulated with Pam 3 Cys and E. coli LPS, ligands of TLR2 and TLR4 respectively, or by centrifugation of the cultures at 141 x g for 30 min, a simulation of orthodontic force, as previously described 1 .…”