Cysteine Cathepsins in Human Carious Dentin

Abstract

A supplemental appendix to this article is published electronically only at http://jdr.sagepub.com/supplemental. ABSTRACTMatrix metalloproteinases (MMPs) are important in dentinal caries, and analysis of recent data demonstrates the presence of other collagen-degrading enzymes, cysteine cathepsins, in human dentin. This study aimed to examine the presence, source, and activity of cysteine cathepsins in human caries. Cathepsin B was detected with immunostaining. Saliva and dentin cysteine cathepsin and MMP activities on caries lesions were analyzed spectrofluorometrically. Immunostaining demonstrated stronger cathepsins B in carious than in healthy dentin. In carious dentin, cysteine cathepsin activity increased with increasing depth and age in chronic lesions, but decreased with age in active lesions. MMP activity decreased with age in both active and chronic lesions. Salivary MMP activities were higher in patients with active than chronic lesions and with increasing lesion depth, while cysteine cathepsin activities showed no differences. The results indicate that, along with MMPs, cysteine cathepsins are important, especially in active and deep caries.

Role of Dentin MMPs in Caries Progression and Bond Stability

“…Also, cysteine cathepsins may participate in dentinal caries development. Cysteine cathepsin activity is different in the various compartments of the caries, depending on the localization and lesion activity (Nascimento et al 2011;Vidal et al 2014). The significant increase of cysteine cathepsin activity in carious dentin with increasing depth toward the pulp (Nascimento et al 2011) indicates that odontoblast or pulp-derived cysteine cathepsins may be important in expediting active caries lesions.…”

“…Together, these findings may indicate saliva as the source of these enzymes. Saliva also contains cysteine cathepsins (Nascimento et al 2011), at least cathepsin B (van Strijp et al 2003).…”

“…More recently, another important family of proteases, the cysteine cathepsins, was reported to be present in dentin (Tersariol et al 2010;Nascimento et al 2011). In terms of protein expression, the variety of these proteases in the dentin-pulp complex has been claimed to be comparable with that described for MMPs (Palosaari et al 2003;Tersariol et al 2010;Tjäderhane et al 2013a).…”

“…2). Within the oral cavity, cathepsins have also been associated with caries progression and failure of adhesive restorations over time (Breschi et al 2008;Liu et al 2011;Nascimento et al 2011;Tjäderhane et al 2013a;Vidal et al 2014).…”

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

“…17 MMP activity has been found to decrease with age in both active and chronic carious lesions. 18 MMPs are secreted to the ECM as inactive proenzymes that require activation for carrying out degradation of matrix components. The pro-form of MMPs is converted into active form by the low pH, but the latter is active only for a short span of time.…”