The inhibitory effect of a polymerisable cationic monomer on functional matrix metalloproteinases

AbstractObjectives tudy examined the use of methacryloxylethyl cetyl dimethyl ammonium chloride (DMAE-CB) as a potential matrix metalloproteinases (MMPs) inhibitor on both soluble recombinant and dentine matrix-bound endogenous MMPs, meanwhile attempted to determine the effective anti-MMP group of quaternary ammonium methacrylates (QAMs). s ssible inhibitory effects of five DMAE-CB mass concentrations (0.1%, 0.5%, 1%, 3%, 5%) on soluble rhMMP-9 were measured using a colorimetic assay kit. Methyl methacrylate (MMA) and [2-(methacryloyloxy)ethyl] trimethylammonium chloride (METMAC) were also screened against rhMMP-9 to compare the inhibitory effect with DMAE-CB. Matrix-bound endogenous MMP-activity was evaluated in completely demineralized dentine beams. Thirty beams were randomly divided into three groups (N = 10) and respectively placed into 500 μL of calcium- and zinc-containing media (CM; control), 0.2% chlorhexidine or 3% DMAE-CB in CM aged for 30 days. The changes in modulus of elasticity, loss of dry mass and solubilization of collagen peptides were measured via three-point bending, precision weighing and hydroxyproline assay, respectively. s mass concentrations of DMAE-CB were highly effective (P < 0.05) in inhibiting rhMMP-9 varied between 76.56 ± 6.44% and 97.06 ± 3.24%, the inhibitory effect of MMA was much lower than that of METMAC and DMAE-CB at the same concentration (P < 0.05). Dentine beams incubated in 3% DMAE-CB showed only a 26.34% decrease in the modulus of elasticity (75.74% decrease in control), a 1.72 ± 1.56% loss of dry mass (29.70 ± 9.12% loss in control), and significantly less solubilized hydroxyproline when compared with the control (P < 0.05). sions B is effective in inhibiting both soluble recombinant MMPs and matrix-bound dentine MMPs. Quaternary ammonium group is the effective anti-MMP group of QAMs. al significance corporation of DMAE-CB into dental adhesives has the potential to enhance the durability of dentine bonding and thus increases the longevity of restorations.