Effects of radiation and alpha-tocopherol on saliva flow rate, amylase activity, total protein and electrolyte levels in oral cavity cancer

Objective: The objective of the present study was to evaluate early and late effects of radiation and a-tocopherol on the secretion rate of saliva and on selected saliva salivary parameters in oral cavity cancer patients. Patients & Methods: Eighty-nine histologically confirmed oral cavity cancer patients (OCC) were enrolled in the study. Resting whole saliva was collected before, during and at the end of the radiation therapy (RT) and simultaneous supplementation with alpha - tocopherol to the radiation treated patients (RT + AT). Results: Salivary flow rate, pH, amylase activity, total protein, sodium and potassium were analyzed. Increased pH, potassium and decreased flow rate, amylase activity, protein content and sodium were observed in 6 weeks of radiation treated patients when compared to OCC patients. A significant improvement of those parameters was observed on alpha - tocopherol supplementation in RT + AT patients. Conclusion: Supplementation with alpha - tocopherol improves the salivary flow rate thereby, maintains salivary parameters.     

The effects of fixed orthodontic appliances on saliva flow rate and saliva electrolyte concentrations

Summary  Fixed appliance orthodontic treatment may affect local saliva secretion; however, there is limited information available about this respect in the literature. Understanding how fixed appliance orthodontic treatment affects local saliva secretion could provide insight on possible contributions of salivary changes towards decalcification. In this study, we found that during the first month of fixed orthodontic treatment, the whole saliva flow rate, upper labial saliva flow rate and concentrations of whole saliva sodium and chlorine increased significantly, while the concentrations of calcium, phosphorous and potassium in whole saliva decreased. However, all these were in normal levels after 3 months. This study demonstrated that saliva flow rate was increased and saliva electrolytes were changed at early stage when placing fixed orthodontic appliances, which was considered due to increased mechanosensation.     

Flow rate,amylase activity,and protein and sialic acid concentrations of saliva from children aged 18, 30 and 42 months attending a baby clinic

Whole-saliva samples were collected under slight suction from children enrolled in a dental-care programme at a baby clinic and analysed according to sex. The children were allocated to three age groups: 18, 30 and 42 months. No distinct sex difference was found for flow rate; there was a statistically non-significant tendency for an increased rate in females. In the males the flow rates of the 30- and 42-month groups were higher than those of the 18-month group; a similar result was obtained when findings for both sexes were combined. There was no difference in salivary protein concentration between the sexes or the age groups. Amylase activity increased significantly in males from 18 to 30 months of age. Sialic acid concentration (micromol/mg protein) showed a sex difference for the 18-month group; it was 38% higher in males than in females, and 48% higher than in the males of 42 months. This trend toward a reduction in sialic acid concentration with age suggests a reduced synthesis and secretion of glycoproteins.     

Interrelationships between flow rate, amylase, calcium, sodium, potassium and inorganic phosphate in stimulated human parotid saliva.

Parotid saliva was collected from 20 healthy young adults using operator-controlled, constant citric acid stimulation and 2 min sampling times over a 10 min period. Timed sequence sampling showed an initial resting period, a transient period prior to amylase release and a steady-state period. Statistically significant interrelationships were established in steady-state samples correlating flow rate with amylase, calcium, sodium and inorganic phosphate; amylase with calcium, sodium and phosphate; sodium with calcium and phosphate; and potassium with phosphate. Physiological bases for interrelationships between amylase, calcium and sodium are postulated to be secretion of calcium as a component of the amylase-containing zymogen granules, and secretion of sodium in association with zymogen granule discharge. The results suggest a dual origin of calcium, and possibly sodium, from both protein and aqueous fractions of saliva.     

Lysozyme activity and flow rate of mixed saliva in children, adolescents and adults

abstract – Reports of lysozyme activity in mixed saliva differ greatly from lysozyme determination in pure form. In this study lysozyme activity of mixed saliva was determined by turbidimetric method in healthy children, adolescents, and adults, 111 subjects altogether. The salivary flow rate was estimated. The lysozyme activity of mixed saliva in 24- children was 129.4 ± 42.4, in 21 adolescents 160.9 ± 58.2, and in 66 adults 165.7 ± 36.7 (|ig/ml hen's egg white lysozyme). The flow rate of mixed saliva was similar in different groups. No statistically significant linear dependence between saliva lysozyme and flow rate was found. The lysozyme activities obtained correspond with the results of saliva lysozyme in pure form.     

Lysozyme activity and flow rate of mixed saliva in children, adolescents and adults.

Reports of lysozyme activity in mixed saliva differ greatly from lysozyme determination in pure form. In this study lysozyme activity of mixed saliva was determined by turbidimetric method in healthy children, adolescents, and adults, 111 subjects altogether. The salivary flow rate was estimated. The lysozyme activity of mixed saliva in 24 children was 129.4 +/- 42.4, in 21 adolescents 160.9 +/- 58.2, and in 66 adults 165.7 +/- 36.7 (mug/ml hen's egg white lysozyme). The flow rate of mixed saliva was similar in different groups. No statistically significant linear dependence between saliva lysozyme and flow rate was found. The lysozyme activities obtained correspond with the results of saliva lysozyme in pure form.     

Influence of flow rate, pH and plasma fluoride concentrations on fluoride concentration in human parotid saliva

In two separate studies the influence of some physiological factors on salivary fluoride excretion was investigated. In the first study, parotid saliva, at two predetermined flow rates, and capillary blood were sampled after ingestion of 1 mg fluoride. In the second study, parotid saliva was collected at five different flow rates, starting 1 h after ingestion of 5 mg fluoride. Capillary blood was sampled throughout the experiment. The first study showed that parotid saliva and plasma fluoride concentrations were closely correlated (r = 0.81). The mean parotid salivary and plasma fluoride concentration ratio (S/P ratio) +/- SD ranged from 0.29 +/- 0.11 to 0.65 +/- 0.15. The fractions of the ingested fluoride dose excreted from one parotid gland were 0.08 and 0.18% at flow rates of 0.25 +/- 0.02 and 0.49 +/- 0.06 ml/min, respectively. The second study showed that at the mean basal plasma fluoride concentration of 0.65 +/- 0.18 mumol/l the mean S/P ratio was 0.55 +/- 0.24. At a plasma fluoride concentration ranging from 3.5 to 11.6 mumol/l the S/P ratio was 0.73 +/- 0.15. Thus the S/P ratio was influenced by the plasma fluoride concentration, but not by variations in parotid salivary flow rate or pH.     

Saliva diagnostics: Salivaomics,saliva exosomics,and saliva liquid biopsy

BackgroundEach day, humans produce approximately 0.5 through 1.5 liters of saliva, a biofluid that is rich in biological omic constituents. Our lack of understanding how omic biomarkers migrate from diseased tissue to the saliva has impeded the clinical translation of saliva testing. Although such biomarkers must be conveyed via the vascular and lymphatic systems to the salivary glands, the molecular mechanisms that underlie this transport remain unclear. Although COVID-19 highlighted the need for rapid and reliable testing for infectious diseases, it represents only one of the many health conditions that potentially can be diagnosed using a saliva sample.Types of Studies ReviewedThe authors discuss salivaomics, saliva exosomics, and the mechanisms on which saliva diagnostics are based and introduce a novel electrochemical sensing technology that may be exploited for saliva liquid biopsy.ResultsThe utility of saliva for screening for lung cancer is under investigation. Saliva testing may be used to stratify patients, monitor treatment response, and detect disease recurrence. The authors also highlight the landscapes of saliva-based SARS-CoV-2 testing and ultrashort cell-free DNA and outline how these fields are likely to evolve in the near future.Practical ImplicationsBreakthroughs in the study of saliva research, therefore, will facilitate clinical deployment of saliva-based testing.     

Temporal variations of glandular kallikrein, protein and amylase in mixed human saliva

Variations in the level of glandular kallikrein in human saliva may reflect physiological changes. Diurnal or circadian variations of many salivary components are important in relating changes in such components to oral or systemic conditions especially as most clinical studies are conducted between 0800 and 1700 h. Whole saliva was collected from 14 healthy young subjects at 0800, 1100, 1400 and 1700 h on two Fridays. Samples were centrifuged at 10,000 g for 10 min at 4 degrees C and the supernatant fractions stored at -20 degrees C. The enzymic activity of kallikrein was measured with D-valylleucylarginine-p-nitro-anilide as substrate. The activity of alpha-amylase and the total protein concentration (biuret) were also determined. Results were analysed in a repeated-measures design: there were no significant differences in kallikrein levels either within days or across days. There were significant differences for total protein and alpha-amylase levels within days but, in general, not across days. Minimal individual levels for protein and alpha-amylase were mostly at 0800 h; maxima were generally at 1400 or 1700 h. Kallikrein levels had no marked pattern of maximal or minimal distribution.     

Saliva flow rate, total protein concentration and osmolality as potential markers of whole body hydration status during progressive acute dehydration in humans

OBJECTIVE: To identify whether saliva flow rate, total protein concentration and osmolality are sensitive non-invasive markers of whole body hydration status, we compared changes in these parameters with changes in body mass during progressive acute dehydration. DESIGN: Twelve euhydrated males reported to the laboratory following an overnight fast and cycled on a stationary ergometer at 60% maximal oxygen uptake in an environmental chamber (30 degrees C and 70% RH) until progressive body mass loss (BML) of 1.1+/-0.0, 2.0+/-0.0 and 2.9+/-0.2%. After exercise, subjects were given a volume of carbohydrate electrolyte solution equivalent to 150% BML to consume within 1h. Unstimulated whole saliva samples were collected over a 2 min period into pre-weighed tubes at pre-exercise, 1.1, 2.0 and 2.9% BML and then at 75, 135 and 195 min post-exercise. RESULTS: Saliva total protein concentration and osmolality increased and flow rate decreased (P<0.01) during dehydration. Saliva total protein concentration and osmolality correlated strongly with % BML during dehydration (mean r=0.97 and 0.94, respectively: P<0.01). The correlation for saliva total protein concentration with % BML was greater (P<0.05) than the correlation for saliva flow rate with % BML (mean r=-0.88: P<0.01) during dehydration. CONCLUSIONS: These data show that changes in saliva total protein concentration and osmolality, and to a lesser extent flow rate, are strongly associated with changes in body mass during progressive acute dehydration.     

Saliva flow rate, buffer capacity, and pH of autistic individuals

The objective of the study was to evaluate saliva flow rate, buffer capacity, pH levels, and dental caries experience (DCE) in autistic individuals, comparing the results with a control group (CG). The study was performed on 25 noninstitutionalized autistic boys, divided in two groups. G1 composed of ten children, ages 3–8. G2 composed of 15 adolescents ages 9–13. The CG was composed of 25 healthy boys, randomly selected and also divided in two groups: CG3 composed of 14 children ages 4–8, and CG4 composed of 11 adolescents ages 9–14. Whole saliva was collected under slight suction, and pH and buffer capacity were determined using a digital pHmeter. Buffer capacity was measured by titration using 0.01 N HCl, and the flow rate expressed in ml/min, and the DCE was expressed by decayed, missing, and filled teeth (permanent dentition [DMFT] and primary dentition [dmft]). Data were plotted and submitted to nonparametric (Kruskal–Wallis) and parametric (Student’s t test) statistical tests with a significance level less than 0.05. When comparing G1 and CG3, groups did not differ in flow rate, pH levels, buffer capacity, or DMFT. Groups G2 and CG4 differ significantly in pH (p = 0.007) and pHi = 7.0 (p = 0.001), with lower scores for G2. In autistic individuals aged 3–8 and 9–13, medicated or not, there was no significant statistical difference in flow rate, pH, and buffer capacity. The comparison of DCE among autistic children and CG children with deciduous (dmft) and mixed/permanent decayed, missing, and filled teeth (DMFT) did not show statistical difference (p = 0.743). Data suggest that autistic individuals have neither a higher flow rate nor a better buffer capacity. Similar DCE was observed in both groups studied.     

Estimation of salivary glucose, salivary amylase, salivary total protein and salivary flow rate in diabetics in India

Diabetes is known to influence salivary composition and function, eventually affecting the oral cavity. We thus evaluated saliva samples for levels of glucose, amylase and total protein, and assessed salivary flow rate in diabetics and healthy non-diabetics. We also analyzed these parameters with regard to duration and type of diabetes mellitus and gender, and aimed to assess the interrelationships among the variables included in the study. A total of 120 age- and sex-matched participants were divided into 3 groups of 40 each; the uncontrolled diabetic group, the controlled diabetic group and the healthy non-diabetic group. Salivary investigations were performed using unstimulated whole saliva. Mean salivary glucose levels were found to be significantly elevated in both uncontrolled and controlled diabetics, as compared to healthy non-diabetics. There were significant decreases in mean salivary amylase levels in controlled diabetics when compared to healthy non-diabetics. Other than salivary glucose, no other parameters were found to be markedly affected in diabetes mellitus. Further research is needed to explore the clinical implications of these study results.     

The effects of flow rate and duration of stimulation on the concentrations of protein and the main electrolytes in human submandibular saliva

At about 8 a.m. on three separate mornings, eight young adults collected two 5-min samples of unstimulated submandibular saliva and then maintained a constant flow rate of 1.0, 2.0 or 3.0 ml/min for 13 min with sour lemon drops as the gustatory stimulus.With stimulation, the pH, ionic strength and the concentrations of protein, sodium, calcium, chloride and bicarbonate increased in proportion to flow rate, the potassium concentration remained almost constant whilst the magnesium and phosphate concentrations decreased, the former being independent of stimulated flow rate but the latter being inversely related to flow rate.Duration of stimulation had slight effects on the protein and potassium concentrations but affected markedly the chloride and bicarbonate concentrations, the former of which rose rapidly at the beginning of stimulation and then fell in a reciprocal manner to the progressive rise in bicarbonate concentration.     

Effect of flow rate on tissue plasminogen activator activity in human parotid saliva

Parotid saliva from 10 healthy volunteers was collected at rest and at constant flow rates of 0.25, 0.5 and 1.0 ml/min, and its tissue plasminogen activator (tPA) activity assayed on fibrin plates containing plasminogen. In unstimulated salivas the median tPA activity was 0.26 (range 0.03-2.0) IU/ml. During the first 15 min of stimulation, a continuous decrease in tPA activity was found at the three flow rates; thereafter a steady state was obtained. No significant differences in activity were found between the three rates. The initial decrease was on average 0.15 IU/ml, and the activity during the steady state was 38% of the prestimulatory level. Thus, stimulation with citric acid causes a significant decrease in tPA activity of parotid saliva but this decrease, as well as the reduction rate, appears to be independent of flow rate.     

Quantitative changes in amylase activity in the salivary glands, pancreas, saliva, and serum after administration of isoproterenol, pilocarpine, and acetylcholine

Amylase activity in various tissues--i.e., submandibular/sublingual and parotid glands, the pancreas, saliva, and serum--in rats was measured after injection of isoproterenol, pilocarpine, and acetylcholine. All agents reduced amylase activity in the parotid gland and increased the enzyme activity in the submandibular/sublingual glands, in saliva and serum.