Proteins In Parotid Saliva Research Articles

Effect of condensed tannin ingestion in sheep and goat parotid saliva proteome

Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep (Ovis aries) and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two-dimensional gel electrophoresis. Matrix-assisted Laser desorption ionization - time of flight (MALDI-TOF) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption.

Quantification of IgA and IgG and specificities of antibodies to viral proteins in parotid saliva at different stages of HIV-1 infection.

Paired sera and parotid saliva from 75 HIV-1-infected patients, divided in three equal groups with CD4+ cell counts > 500, 200-500 and < 200/mm3, respectively, were analysed for IgG, IgA and secretory IgA (sIgA) concentrations and for IgG and IgA antibody directed to HIV-1. Twenty-nine age-matched HIV-subjects were used as controls. In serum the concentrations of immunoglobulins were significantly increased in HIV-infected subjects compared with controls, and a progressive increase of IgA and sIgA was noticed while the CD4+ cell count decreased. In contrast, concentrations of IgA and sIgA were not different in parotid saliva between the four subject groups. By an ELISA test directed towards HIV-1 proteins, 73 of the 75 serum specimens from the HIV-infected subjects (97%) and 43 of the corresponding saliva (57%) were found positive for specific IgA antibodies to HIV-1, with an even distribution among the three groups of patients. By Western blotting multiple specificities of IgA to HIV-1 proteins were not frequently found in patients. By contrast, in spite of an IgG concentration in saliva about 100 times lower than that of IgA, reactivities were significantly higher for IgG than for IgA antibodies, especially to env and to pol HIV-1 products. Altogether, these data suggest that the regulation of IgA production in HIV-infected subjects is independent in serum and in parotid saliva. This imbalance of IgA/IgG antibodies to HIV-1 at the mucosal level appears to be a specific feature of HIV-1 infection, and may raise important issues in terms of local protection after immunization.

Lactoferrin iron levels are reduced in saliva of patients with localized aggressive periodontitis.

Actinobacillus actinomycetemcomitans (Aa) is associated with localized aggressive periodontal disease in juveniles (LAgP). Lactoferrin (LF) is an iron-binding salivary protein that has been shown to kill Aa in its iron-free form (apo) and reduce binding to host cells in its iron-saturated form (halo). However, recent in vitro studies show that LF does not kill clinical isolates of Aa, and LF with reduced levels of bound iron does not interfere with its attachment. These findings suggest that colonization of Aa may occur more readily in an environment containing LF with low iron levels. The purpose of this study was to examine the relationship of LF iron levels in saliva of LAgP patients as compared to their age-, gender-, and race-matched controls. Whole and parotid saliva was collected from LAgP patients and matched controls. Micrograms of LF/mg of protein as well as nanograms of iron/micrograms of LF were determined. Iron binding was determined in parotid saliva by addition of nonlabeled and 59Fe labeled iron. LAgP patients' whole saliva had higher LF levels than controls, but their LF contained less iron (P < or =0.005). No iron was found in LF from parotid saliva in either group. When iron was added to parotid saliva, the LAgP saliva bound 20 to 30 times less iron than controls (P< or =0.001). Finally, LF was identified as the major iron-binding protein in parotid saliva by 59Fe autoradiography and Western blotting. This study shows that the level of bound iron in LF is significantly reduced in LAgP patients compared to controls. These data suggest that LF from LAgP patients has a reduced capacity to bind iron and that LF iron levels may play an important role in Aa-induced LAgP.

Gustin from Human Parotid Saliva Is Carbonic Anhydrase VI

Gustin, a zinc-metalloprotein constituting about 3% of human parotid saliva protein was previously isolated and characterized as a single polypeptide chain of 37kDa with one mole of zinc tightly bound to the protein. It exhibited biological activity activating calmodulin dependent bovine brain cAMP phosphodiesterase and was decreased in saliva of patients with loss of taste in whom taste buds showed a specific pathological morphology. Determination of its primary structure by amino acid sequence revealed it was identical with carbonic anhydrase (CA) [EC 4.2.1.1] VI and had two N-linked glycosylation sites. Analysis by reverse phase HPLC and SDS–PAGE before and after deglycosylation confirmed a single peak with molecular weight of the purified protein being 37kDa, the deglycosylated protein, 33kDa. N-linked carbohydrate chains contained N-acetyl glucosamine, galactose, mannose, and fucose interior to di, tri and tetra sialyated termini. By isoelectric focusing five increasingly acidic pI values were determined consistent with addition of sialic acid as the terminal carbohydrate residue on the N-linked glycoforms of the protein. Gustin was found to exhibit CA activity but was inhibited by known CA inhibitors in a different manner than CA I or II. These findings, consistent with analysis of previous investigators, indicate that parotid saliva gustin is CA VI.

Parotid saliva protein profiles in caries-free and caries-active adults

Objective. The objective of this study was to determine if there were any differences in the parotid saliva output and composition related to caries activity. Study design. Stimulated parotid saliva samples were collected from 85 healthy young adults, caries-active or caries-free. Flow rates were determined, and samples were analyzed for pH and buffer capacity, total protein, electrolytes, proteins with a high performance liquid chromatography method, and histatins. Results. There were no differences in flow rates or pH, but buffer capacity was higher in women than in men, and K + and Cl − were both slightly higher in the caries-active group. The women had a significantly higher total protein concentration, as well as higher concentrations of each of the individual protein components assayed. There were no differences attributable to caries activity. Conclusions. Significant sex differences in salivary protein concentrations exist. Caries activity may be related to some salivary electrolyte alterations, but not to protein composition.

Effects of protein deficiency and diet consistency on the parotid gland and parotid saliva of rats.

Protein deficiency results in an increased susceptibility to dental caries, suggesting that oral host-defense properties are compromised. An important component of oral host defense is salivary gland function, which is affected by both protein deficiency and diet consistency. This study describes the effects on rat parotid gland growth and secretory function induced by feeding rats diets of normal (20%) or moderately low (7%) protein content, provided in either a powdered or solid form. In addition, since protein deficiency may result in a secondary zinc deficiency which, in turn, may affect salivary gland function, the effects of these diets on liver zinc concentration were also measured. From 22 to 47 days of age, rats (18/group) were fed the following diets: normal protein, powdered; normal protein, solid; low protein, powdered; and low protein, solid. With each diet consistency, liver zinc was higher for the normal protein group. Within each protein level, liver zinc was higher for the solid diet. This latter observation suggests that food mastication and the resultant stimulation of salivary gland function may also play a role in zinc metabolism. With the normal-protein diet, parotid gland weight was higher for the solid diet; with the low-protein diet, parotid gland weight was similar for both consistencies and did not differ from that of the group fed the "normal protein, powdered" diet. For both consistencies, parotid saliva protein concentration was greater for malnourished rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Radioimmunoassay for salivary carbonic anhydrase in human parotid saliva

A specific radioimmunoassay for human carbonic anhydrase (CA) VI has been developed and used to determine the concentrations of the enzyme in saliva. The assay detected as little as 200 pg of CA VI and the antibody used did not cross-react with CA II or other salivary proteins. The method showed an intra-assay variation of 8.5% and an inter-assay variation of 16.9%. The concentration in parotid saliva varied over a wide range (from 9.7 pg/ml to 121 μg/ml) with an average value of 47.0 ± 39.2 (SD) μg/ml( n = 50). The mean secretion rate of CA VI from the combined parotid glands was 42.8 ± 37.9 μg/min CA VI represented about 3% of the total protein in parotid saliva.

Pilocarpine Alters Caries Development in Partially-desalivated Rats

This study examined the effect of pilocarpine on caries and saliva composition in rats with compromised salivary gland function. Eight litters of specific-pathogen-free female Sprague-Dawley rats were divided into five groups for surgery. Partial desalivation was performed in either of three ways: (1) Both parotid ducts were ligated; (2) both submandibular/sublingual (SM/SL) glands were excised, or (3) one parotid duct was ligated, and submandibular/sublingual glands were removed unilaterally. Completely desalivated animals and unoperated animals served as positive and negative controls, respectively. One week following surgery, groups were subdivided so that half of each group had osmotic pumps implanted which delivered pilocarpine HCl (24 mg/kg/day). All animals were infected with Streptococcus sobrinus 6715 and fed cariogenic diet ad libitum for 28 days. Caries scores, microbiological data, and saliva flow rate and composition were determined for all animals. Animals which had both SM/SL glands removed and received pilocarpine developed significantly lower sulcal caries (p < or = 0.05) compared with the animals that had both SM/SL removed but did not receive pilocarpine. The concentration of protein in parotid saliva in these pilocarpine-treated animals was unaffected, and no differences were observed in the electrophoretic profiles on SDS-PAGE. Pilocarpine appears to exert its greatest caries-protective effect when the parotid glands remain intact.

Zinc, magnesium, copper, and protein concentrations in human saliva: age- and sex-related differences

Normal concentrations of trace elements in parotid saliva, supernatant- and sediment-mixed saliva, plasma, and hair were determined in 278 healthy adults grouped as young (18-29 y), middle-aged (30-64 y), and elderly (65-93 y). Age-related increases (p less than 0.05) were observed in concentrations of zinc in the supernatant of mixed saliva and parotid saliva, copper in plasma, and protein in all fractions of saliva studied. Concentrations of zinc in salivary sediment and plasma did not vary with age. Age-related decreases (p less than 0.05) were found in concentrations of magnesium in mixed-saliva supernatant, copper in salivary sediment, and zinc and copper in hair. Males had higher concentrations of zinc in plasma (p less than 0.05) and of copper in sediment (p less than 0.01) than did females but lower amounts of copper in plasma and of protein in parotid saliva (p less than 0.05). Concentrations of zinc in saliva were not correlated with those in plasma or hair. Copper in mixed-saliva supernatant was positively associated with concentrations in plasma but negatively related to concentrations in hair.

Altered bacterial aggregation and adherence associated with changes in rat parotid-gland salivary proteins induced in vivo by β-adrenergic stimulation

Reduced adherence and aggregation were associated with protein alterations in parotid saliva after chronic treatment with the β-adrenergic agonist isoproterenol. In contrast, saliva from animals treated with the β-antagonist, propranolol, did not cause such changes; the protein composition of this saliva was similar to that of controls. SDS-polyacrylamide gel electrophoresis of protein in saliva samples before and after they were mixed with 10 mg of spheroidal hydroxyapatite beads (HA), as well as protein adsorbed and recovered from the HA, showed that an acidic, proline-rich protein with a molecular weight of approx. 40,000 was the predominant protein adsorbed. This protein was significantly diminished in saliva from isoproterenol-treated rats. Proteins with molecular weights between 44,000 and 48,000 and unique to the saliva from isoproterenol-treated animals were also adsorbed to HA. Thus alterations in proline-rich proteins of parotid saliva may influence the adherence and aggregation of oral bacteria, two processes considered important for in-vivo colonization of oral surfaces.

Changes in rat parotid saliva protein composition following chronic reserpine treatment and their relation to inanition

Chronic administration of the catecholamine-depleting agent, reserpine (0.5 mg/kg), resulted in a reduction in food intake after 3 days. To differentiate effects of the drug from those of reduced food intake a pair-fed group, whose daily caloric intake was restricted to the amount consumed by the reserpine-treated rats, was included. After 7 days, both the reserpine-treated and pair-fed control exhibited a marked reduction in the volume of saliva collected in a 30 min interval following a secretory stimulus compared to untreated ad libitum-fed controls, and the proportion of salivary proteins attributable to acidic and basic proline-rich proteins and to minor Ib protein were decreased whereas deoxyribonuclease was increased. For two of the salivary proteins (fractions I and V) changes for the reserpine-treated and pair-fed groups were different. Fraction I was reduced in both groups, but exhibited a greater decrease in the pair-fed than in the reserpine-treated, whereas fraction V was significantly increased only in the pair-fed group. Thus many of the salivary changes associated with reserpine treatment may have resulted from the change in feeding habits and not from reserpine treatment per se. The study demonstrates the importance of controlling for food intake under experimental circumstances which may lead to a marked change in daily feeding habits.

Effect of Radioactive Iodine Therapy on Parotid Gland Function

In 37 males and females with thyroid carcinoma, treated with radio-iodine, parotid gland function was investigated before and one week after therapy. 34 subjects remained free of complaints and showed no effect of 'I-therapy on parotid flow rate. Following therapy, all of them showed alterations in the composition of parotid secretion, especially enhanced values for a-amylase activity, protein concentration and sodium concentration. Three subjects developed acute parotitis of the obstructive sialadenitis type. In these patients, flow rate was severely reduced. The values for PHI, sodium, a-amylase and protein in parotid saliva were markedly elevated. Just as in chronic recurrent parotitis, increased activity of salivary glandular kallikrein in radio-iodine sialadenitis was measured.

Effect of Radioactive Iodine Therapy on Parotid Gland Function

In 37 males and females with thyroid carcinoma, treated with radio-iodine, parotid gland function was investigated before and one week after therapy. 34 subjects remained free of complaints and showed no effect of 131I-therapy on parotid flow rate. Following therapy, all of them showed alterations in the composition of parotid secretion, especially enhanced values for alpha-amylase activity, protein concentration and sodium concentration. Three subjects developed acute parotitis of the obstructive sialadenitis type. In these patients, flow rate was severely reduced. The values for PHI, sodium, alpha-amylase and protein in parotid saliva were markedly elevated. Just as in chronic recurrent parotitis, increased activity of salivary glandular kallikrein in radio-iodine sialadenitis was measured.

Electrophoretic characterisation of human parotid saliva protein fractions isolated by preparative isoelectric focusing

AbstractHuman parotid saliva proteins fractionated by preparative isoelectric focusing into 3 main fractions have been characterised electrophoretically and immunochemically. The anodic proteins constitute a polymorphic family of collagenase and trypsin sensitive, immunochemically related, phosphoproteins. Many of these contain a common polypeptide of Mr 23 000 either alone or in combination with other lower (Mr 21 000) or higher (Mr 25 000) molecular weight polypeptides. Parotid amylase was substantially purified by this technique and an antiserum against these fractions reacted monospecifically with amylase in a number of systems. The cathodic proteins are all collagenase sensitive proteins with Mr values of 12 500 to 77 000.

Human parotid saliva protein composition: dependence on physiological factors.

The relative concentrations of the major proteins in human parotid saliva as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis varied greatly between the six individuals included in this study but were remarkably constant for a given individual. Individual relative parotid protein concentrations differed in salivas collected under unstimulated and stimulated conditions but were at least partially independent from circadian and feeding effects. In addition, the relative concentrations of certain salivary proteins decreased with continued lemon-drop stimulation. A total of 29 different bands was composited from the six subjects. Five of the bands had mobilities corresponding with those of calibration proteins selected for their known occurrence in parotid saliva. Only those proteins comprising at least 0.75% of the total protein concentration were detected. Relative protein concentrations of parotid saliva samples collected 12 mo apart from given individuals were identical.

Electrophoretic protein pattern of human parotid saliva in Sjögren's syndrome and sialosis.

The electrophoretic pattern of the basic proteins in parotid saliva was examined in 12 control subjects and 45 patients suffering from xerostomia and parotid swelling of diverse origins. The protein pattern in the control subjects did not differ from the observed in sialotic patients. Characteristic quantitative and qualitative alterations in protein composition were observed in Sjögren's syndrome. The concentration of the protein fractions with a low Rp value showed a considerable increase, while one or two additional protein bands with high Rp value could be detected in these patients. The appearance of these additional protein bands may prove to be a valuable laboratory indicator in the diagnostic work. If they really indicate the beginning of an autoimmune process, the disease could be diagnosed much earlier than by the methods available today.

Genetic polymorphism of vitamin B12 binding (R) proteins of human saliva detected by isoelectric focusing

Genetic polymorphism of the vitamin B12 binding (R) proteins of parotid saliva is determined by autosomal inheritance of codominant alleles. This hypothesis is supported by studies in 43 families including 152 children. For randomly collected salivas from 143 whites, 104 blacks, and 75 Chinese, gene frequencies are as follows: for whites, Rs1=0.88, Rs2=0.12; for blacks, Rs1=0.94, Rs2=0.06; for Chinese, Rs1=1.00. This genetic marker is also shared by R proteins of milk, tears, and leukocytes. In the Rs 1--2 salivary type there is less labeling of the protein products of Rs2 v. Rs1 with 57Co B12 as assessed by the intensity of the bands on the autoradiogram. There is no evidence for close linkage (theta less than 0.01) between Rs and TC II (transcobalamin II) or between Rs and salivary protein locus Pr, Db, Gl, or Ps.

Immunological comparison of proline-rich proteins from human and primate parotid secretion

Antisera raised in response to proline-rich proteins purified from parotid secretions of man and the primate Macaca fascicularis were employed to investigate the interrelationships of these proteins by immunodiffusion, immunoelectrophoresis and the combined use of disc gel acrylamide electrophoresis with radial immunodiffusion. The major human proline-rich proteins, PRP I, PRP II, PRP III and PRP IV as well as several minor proline-rich proteins cross-react with antiserum to PRP I or PRP III. Similarly primate parotid saliva contains several components cross-reacting with antiserum directed against a purified primate proline-rich protein, MPRP. Antiserum to PRP I or PRP III cross-reacted with MPRP and primate parotid saliva protein, whereas antiserum to MPRP cross-reacted only with human parotid saliva protein and not with the isolated human proline-rich proteins. The immunological relationships of these salivary proline-rich proteins within and between species suggest their origin from a common precursor molecule.

Genetic polymorphism of the major parotid salivary glycoprotein (Gl) with linkage to the genes for Pr, Db, and Pa.

Genetic polymorphism of the major glycoprotein (Gl) found in parotid saliva is determined by autosomal inheritance of one unexpressed and four expressed alleles. This hypothesis is supported by studies in 41 white families including 146 children. For 143 randomly collected salivas from whites and 82 randomly collected salivas from blacks, maximum likelihood estimates of the gene frequencies are as follows: for whites, Gl1 = 0.742, Gl2 = 0.040, Gl3 = 0.155, Gl4 = 0.017, Gl0 = 0.46; for blacks, Gl1 = 0.459, Gl2 = 0.050, Gl3 = 0.337, Gl4 = 0.044, Gl0 = 0.110. There is strong evidence for linkage of Gl/Pr (seven families, lod score at theta = 0 is 5.24) and G1/Db (eight families, lod score at theta = 0 is 4.45). The allelic products of Gl show evidence for linkage disequilibrium with the products of the Pr, Db, and Pa loci (P less than 0.0005). On the basis of varying degrees of linkage disequilibrium, Gl may be closer to Db than to Pr or Pa and on the "outside" of Db with respect to Pr or Pa. Amino acid analyses of Gl 1 and Gl 4 proteins show strong resemblances in composition to the major basic glycoprotein and the acidic proline-rich proteins of parotid saliva described by other workers. The polymorphic forms of the Gl proteins show microheterogeneity due to variability in charge and molecular weight. The electrophoretic polymorphism appears to be determined by apparent differences in molecular weights between the Gl proteins.

The basic proline-rich proteins in human parotid saliva from a single subject

Eleven Chromatographic fractions of basic proline-rich proteins isolated from parotid saliva from a single donor showed similar but not identical chemical compositions; proline, glycine and glutamic acid-glutamine accounted for 70–80 per cent of the total residues in the proteins. The basic amino acids, lysine and arginine, accounted for a further 10 per cent. All the proteins were in freshly-collected saliva and did not result from post-secretory proteolysis. The most basic of the proline-rich proteins, I-B9, was purified and characterized. The amino terminal residue was serine and the carboxyl terminal residue arginine. The molecular weight determined by quantitative end-group analyses was 9000–9500. Protein I-B9 was resistant to hydrolysis by collagenase and Staphylococcus aureus protease, whereas papain and subtilisin extensively degraded it. I-B9 fragments from clostripain and elastase digestions were isolated for use in sequence determination. Basic proline-rich proteins, acidic proline-rich proteins and proline-rich glycoprotein accounted for 23, 30 and 17 per cent, respectively of the total protein in the parotid saliva.