Atividade antiproteolítica da emulsão à base de óleo de Copaifera Multijuga hayne: efeito nas metaloproteinases

Abstract

Composite resin is one of the most used materials to restore the tooth through the use of adhesive systems, however, in these bonding of adhesive systems to the tooth some problems that affect the longevity of this treatment occur, especially in the hybrid layer. In the dentin extracellular matrix are endogenous proteases that are responsible for denaturing and degradation of dentin collagen fibers, inhibition of these enzymes is crucial for the preservation of the hybrid layer and clinical success. The objective of this work was to evaluate the effect of copaiba oil-based emulsions at different preservative concentrations on the inhibition of metalloproteinases MMP-2 and MMP-9; cytotoxicity in HT1080 cells and in situ antiproteolytic activity using the conventional self-etching adhesive system. In situ zymography the thirty teeth were sectioned 2 mm below the enamel-dentin junction, then standardized to the smear layer and divided into four groups. Fluorescein-conjugated gelatin was used and then taken under the fluorescence microscope for evaluation. The cytotoxicity of the solutions was tested using the Trypan Blue method at 15 seconds, 30 seconds, 10 and 20 minutes. The groups tested were: (G1) control with distilled water; (G2) 2% Chlorhexidine Digluconate (CLX); (G3) 10% copaiba oil (EC) based emulsion + X; (G4) 10% EC + Y; and (G5) 10% alkaline EC. The zymographic test was performed by analyzing the same groups described above, but at times of 30 seconds, 10 and 20 minutes. HT1080 cells were incubated, and subjected to SDS-PAGE gel electrophoresis. After the run, the gel was stained and the band images were analyzed using ImageJ software. Statistical analysis used the nonparametric Mann-Whitney test for two medians and Kruskal-Wallis (p <0.05) for more than two medians. In the cytotoxicity test, the ECs presented higher cell viability when compared to CLX in all tested times, presenting a statistically significant difference at 10 and 20 minutes. In the zymographic assay, EC showed activity on MMP 2 and MMP 9, however the one that presented the best result was 10% alkaline EC in 10 minutes of treatment, alkaline EC reduced by 67% the activity of MMP 2 and 44%. MMP 9 compared to 2% chlorhexidine digluconate. In situ zymography there was no statistical difference between the tested groups, however in the qualitative evaluation all tested groups showed inhibition of activity on metalloproteinases. Thus, the emulsions based on the oil of copaiba showed activity in the inhibition of metalloproteinases in vitro and in situ studies, showing a potential as a biomodifier that presented the best results was the alkaline Ec.