Saliva: A Fluid of Study for OMICS

Abstract

Saliva is a fluid that can be collected easily and noninvasively. Its functions in the oral cavity are well known. Advances in molecular biology and technology, as well as research conducted by the various disciplines of omics (genomics, transcriptomics, proteomics, metabolomics, and metagenomics) have contributed to the identification and characterization of salivary components, including DNA, RNA, proteins, metabolites, and microorganisms. These biomolecules enter the saliva through extracellular and intracellular routes, providing information from several organs and systems and raising the possibility of their use as disease biomarkers. In recent years, these factors have expanded the potential use of saliva as a diagnostic fluid for oral and systemic diseases. This review integrates information regarding salivary biomolecules studied through omics and explores their utility as biomarkers for the diagnosis of several infectious and noninfectious diseases, and the opportunity they represent for the development of point of care devices for clinical application. We also discuss the advantages, disadvantages, and challenges to be overcome in order to establish saliva as a useful fluid for the accurate diagnosis and monitoring of a wide range of diseases.

Human salivary proteome — a resource of potential biomarkers for oral cancer

“…These enzymes may also be involved in the initiation of digestion of food components in the oral cavity. The other major category of proteins identified were the transport/carrier proteins apolipoprotein B (APOB), albumin (ALB) and apolipoprotein H (APOH) that might have been detected in saliva through leakage from blood [34,35]. Calcium binding proteins such as calmodulin-like (CALML5), calcium binding protein 39 (CAB39), members of S100 family (S100A7, S100A8, S100A9, S100A11) and annexin family members (ANXA1, ANXA2, ANXA3) were also identified in saliva.…”

The Neonatal Salivary Transcriptome

“…Saliva is also a rich source of microorganisms, including viruses, bacteria, and fungi, whose composition may serve as a window into the overall health status of an individual. Comprehensive reviews of adult saliva have been previously written and can be found elsewhere (Lawrence 2002;LlenaPuy 2006;Tiwari 2011;Cuevas-Có rdoba and Santiago-García 2014).…”

The foodomics approach for discovering biomarkers of food consumption in nutrition studies

“…The majority of the published nutritional metabolomics studies focus on urine samples [16 ], but recently Hanhineva et al [21 ] demonstrated the impact of dietary intervention also on the metabolic profile in fasting plasma, and fecal metabolome has been also investigated to evaluate the effect of specific food [36]. Other organic fluids, that is, saliva [37] and the cerebrospinal fluid [38], have been used in humans and animals. Anyway, most studies investigating human metabolomics measurements are limited to a single biofluid, while an approach to generate an integrated picture of metabolomics associations over multiple fluids would be needed.…”