Exploring salivary proteomes in edentulous patients with type 2 diabetes

Abstract

Type 2 diabetes and tooth loss are linked both epidemiologically and pathophysiologically. We applied label-free differential protein expression analysis using multidimensional liquid chromatography/tandem mass spectrometry (2D-LC-MS/MS) to explore the proteomic profile of saliva samples collected from selected type 2 diabetic edentulous patients and non-diabetic controls. Ninety-six peptides corresponding to 52 proteins were differentially expressed between the diabetic edentulous patients and controls (p < 0.05). Some diabetes-related inflammatory biomarkers including glyceraldehyde-3-phosphate dehydrogenase and serum amyloid A were detected with levels increased in diabetic samples. Other biomarkers including amylase, palate, lung and nasal epithelium associated protein (PLUNC), and serotransferrin levels were decreased in diabetic samples. In contrast with previous findings, salivary carbonic anhydrase 6 and alpha-2 macroglobulin levels, however, were decreased in this diabetic patient population. Cluster analysis and principle component analysis demonstrated a differential pattern of protein biomarker expression between diabetic and control subjects. Western blot analysis was completed to confirm the relatively lower expression level of two biomarkers, including PLUNC and amylase in the diabetic group compared to control subjects. The presence of salivary biomarkers specific for diabetes in edentulous subjects mimics those in serum, especially those related to inflammatory/lipid metabolism. While this exploratory study requires further validation with a larger population, it provides proof-of-principle for salivary proteomics for edentulous subjects with diabetes.

Saliva as a diagnostic tool for oral and systemic diseases

“…A recent study reported the salivary proteomic profile of type 2 diabetes patients. 36 The authors found that 52 proteins were differently expressed and higher levels of some diabetesrelated inflammatory biomarkers were observed in saliva of individuals with diabetes compared to controls. Other investigators have reported that among a total of 487 analysed proteins in the saliva, 65 had higher levels in type-2 diabetes subjects compared to healthy individuals.…”

MECHANISMS IN ENDOCRINOLOGY: Proteomic biomarkers of type 2 diabetes mellitus risk in women with polycystic ovary syndrome

“…Studies were excluded if they were review articles, proteomic techniques were not used or if they did not compare T2DM with a healthy control group. Six studies involving animals only and two comparing different proteomic approaches were further excluded leaving nine primary studies (30,31,32,33,34,35,36,37,38) evaluated in this review. Further searches of the Cochrane and EMBASE databases and hand searching of the references of relevant manuscripts did not yield additional articles.…”

“…Six out of the nine studies were classified as HQ fulfilling at least ten out of the 16 criteria (30,31,33,34,35,37). The three remaining studies were classified as LQ achieving 8 or 9 out of the 16 quality (32,36,38).…”

“…In the studies, the samples were collected from different sites: serum in five studies (32,33,36,37,38), saliva in three studies (30,31,35) and Cadaveric pancreatic islet cells in one study (34). With the exception of one study, the selection criteria were overall adequately described (32).…”

Automated Mass Spectrometry–Based Functional Assay for the Routine Analysis of the Secretome

“…[1][2][3][4][5][6]8 Secretomes may be classified according to various criteria, such as the type of the cell or the type of the tissue producing the secretome, or the location of the secreted proteins such as extracellular but nonsystemic, intraorgan (e.g., intrahepatic) or extracellular but systemic, extraorgan (e.g., blood, saliva, urine, or lymphatic fluid). [16][17][18][19][20][21][22][23][24][25][26][27][28][29] Depending on the type of secretome analyzed, specific information may be obtained. For example, analysis of proteins secreted by cells grown in cell culture will reflect the health and activity of those cells.…”