Salivary cystatins - biological role and diagnostical value

Abstract

Introduction: This paper provides insights of the latest studies regarding the structure, properties and taction of cystatins belonging to family II, salivary cystatins in particular. Materials and methods: Relevant articles on the topic for the period from 1996 to 2013 were analyzed, using PubMed database and the following key words: cystatins, cystein proteases, and salivary cystatins. Results: Nowadays the cystatinsuper family is known to comprise about 30 members.The members of cystatin family II -cystatin C, D, S, SA, SN, E/M and F, are found in body fluids. Their involvement in inflammatory processes, cancerogenesis and metastasis, bone remodeling and in other processes has been undoubtedly demonstrated.Cystatins S, SN and SA were found in submandibular and sublingual glands, while cystatin D was detected only in parotid glands. Salivary cystatinsS, SN, SAand D contribute to the maintenance of the oral health through the inhibition of endo- and exogen cysteine proteases, antimicrobial and antiviral protection and regulation of hard tooth tissue remodeling. Conclusions: Studies of major significance attest the clinical utility of cystatins’ assay (cystatin C) for the diagnosis of some diseases (for ex. renal failure). In addition, cystatin C, among other cystatins, decreases the formation of osteoclasts by interfering at a late stage of pre-osteoclast differentiation.Cystatin D is produced by the parotid gland and is secreted through blood serum to the whole body, similar to a hormone, and thus there are set new research directions of cystatins as markers of diseases, including the ones causing oromaxillofacial pain, prosopalgia, and the monitoring of disease’s evolution and of treatment efficiency.