Protease inhibitor concentrations in the saliva of individuals experiencing oral dryness

Abstract

Background Oral dryness is a common symptom that may interfere with swallowing, chewing, and taste. The most common reason for oral dryness is hyposalivation. Some individuals experiencing oral dryness do not have hyposalivation, however, and the reverse is also true. Here, we focused on healthy individuals with a lower salivary flow rate and evaluated the relationship between the perception of oral dryness and salivary parameters to clarify the cause underlying the perception of oral dryness. Methods A total of 59 participants were divided into 2 groups with a lower or higher salivary flow rate according to the median salivary flow rate. In participants with a lower salivary flow rate, we assessed salivary bacterial counts, protease activities, protein concentrations, oral parameters, and the subjective perception of oral dryness. Results Protease activities and concentrations of protease inhibitors such as cystatin-D and cystatin-SA in the saliva of participants experiencing oral dryness were significantly higher and lower, respectively, than in those not experiencing oral dryness, even though no difference in the salivary flow rate was detected. Salivary cystatin-D and cystatin-SA concentrations correlated negatively with salivary protease activities. Conclusions The composition of salivary protease inhibitors and increased protease activities affect the subjective perception of oral dryness.

Proteomic Profiling of Saliva and Tears in Radiated Head and Neck Cancer Patients as Compared to Primary Sjögren’s Syndrome Patients

“…In terms of clinical relevance, histone modification has previously been suggested as a new treatment in pSS [ 43 ], and the results from the present study indicate that they may play a role in other dry mouth conditions as well. Furthermore, cystatins have been reported to be in lower concentrations in subjects with xerostomia compared to subjects with similar salivary flow rates [ 44 ]. The current study suggests that this should be explored further, and may help in understanding the lack of correlation between symptoms and objective findings in dry mouth [ 45 ].…”

Biodistribution of Fluorescent Albumin Nanoparticles among Organs of Laboratory Animals after Intranasal and Peroral Administration

“…Most inhibitors are highly specific for single or several related proteinases whereas the α-2-macroglobulin and the alpha 1-proteinase (α-1-antitrypsin) have a broader specificity [19]. Mucosal swabs and saliva also contain a number of proteins, including mucin, histatin, cystatin, statherin, amylase, lingual lipase, secretory immunoglobulins and proline-rich protein [20]. These proteins maintain tooth and mucosal integrity, mucosal immunity and are involved in digestion, lubrication, buffering and antibacterial activity [20].…”

Comparison of proteins with anti-influenza virus effects in parotid and submandibular-sublingual saliva in humans

“…Cystatins, which are salivary cysteine protease inhibitors, have antimicrobial and protease inhibitory properties [ 12 , 25 , 26 ], however, anti-IAV activity of cystatins is unknown. The findings of the present study demonstrated high concentrations of cystatin family members in SMSL saliva that positively correlated with anti-IAV activity.…”

“…Salivary proteins were identified by mass spectrometry according to previously described methods [ 16 , 25 ]. For ultrafiltration, 300 µL of each type of saliva was diluted with 200 µL of 100 mM Tris/HCl buffer (pH 8.5), transferred to a 3-kDa-cutoff Millipore ultrafiltration device (Merck KGaA, Darmstadt, Germany), and centrifuged at 14,000 g at 4 °C for 30 min.…”