The effect of Salinum on the symptoms of dry mouth: a pilot study

The effect of a new saliva substitute. Salinum®, was tested in 37 patients with severe symptoms of reduced salivation. The majority of the patients had suffered from hyposalivation and dry mouth for more than 8 years. The saliva substitute consisted of a water soluble extract of linseed. The physical properties of this extract are similar to those of the glycoproteins of the salivary secretions. The patients used the saliva substitute for a seven days period. Prior to the use of the extract the patients reported that the most severe symptoms of decreased salivation were a feeling of dryness in the mouth and burning sensations in the tongue, pharynx and oesophagus, The majority of the patients reported that the use of Salinum reduced the symptoms of hyposalivation. Great variation in effect occurred from patient to patient. Generally the patients with the most severe symptoms experienced the greatest relief of the symptoms when they used Salinum. Although of short duration the results of this pilot study indicate that an extract of linseeds may compensate for some aspects of the consequences of reduced salivation. Further studies are needed to elucidate the feasibility of the extract as saliva replacement.     

Analysis of secretory immunoglobulin A in human saliva by laser-induced fluorescence capillary electrophoresis

The utility of capillary electrophoresis (CE) has been demonstrated for the analysis of secretory immunoglobulin A (sIgA) in human saliva. The amount of sIgA in saliva correlates with immune status. For detecting salivary sIgA, laser-induced fluorescence was conducted in this report for signal amplification. sIgA and anti-sIgA antibody were labeled with cyanine fluorescence (Cy5) for competitive immunoassay and non-competitive analysis, respectively. Cy5 was excited by He-Ne laser with a wavelength of 635 nm, with maximum emission at 670 nm. Migration time during electrophoresis depended on whether sIgA-Cy5 was mixed with antibody or anti-sIgA-Cy5 mixed with sIgA to form Ag-Ab complex. The results indicated that CE competitive immunoassay was effective for analyzing serum sIgA, but not for salivary sIgA. However, salivary sIgA can be analyzed by complex formation assay. The peak area of the complex was proportional to the amount of sIgA added. A standard linear regression curve was generated using purified sIgA. From this standard curve, the amount of sIgA from saliva of either normal or immunocompromised patients can be calculated from the Ag-Ab complex peak area.     

Fluid transport across the ducts of the salivary glands of a mosquito

We compared the volumes of fluid expelled from the salivary stylets of mosquitoes having ducts transected at different levels. An oil-filled apparatus was devised to measure salivary output. About $\text{1}\text{10}$ of normal salivary volume was produced by mosquitoes when ducts were transected and externalized just anterior to the salivary glands. Such mosquitoes ejected more saliva than could be contained within the walls of the ducts. Transection posterior to the pump prevented salivation entirely. Skin reactive antigen was not detected (as a wheal) when mosquitoes with transected ducts fed on man. We conclude that fluid is transported across the walls of the ducts that drain the salivary glands of a mosquito.     

Major salivary gland output differs between users and non-users of specific medication categories

Background: The intake of medications is a major aetiologic factor of xerostomia. The purpose of this study was to investigate the selective influence of medication categories on flow rates of individual major salivary glands. Methods: The effect of each medication category on salivary flow rates was determined by dichotomy comparisons between users and non‐users. A total of 246 patients were included, 79 males and 167 females aged 13–92 years (mean 63 years). Of these, 200 used medications, which were grouped according to their category. A comprehensive medical and oral examination was performed. Both unstimulated and stimulated saliva was collected separately from the parotid and submandibular/sublingual glands. Results: Parotid flow rate was decreased among users of tranquillisers and sedatives (unstimulated flow), cardiovascular drugs and gastrointestinal drugs (stimulated flow). Submandibular/sublingual unstimulated output was lower in patients taking cardiovascular drugs, antihistamines, tranquillisers/sedatives and antidepressants, while the stimulated flow, in those taking cardiovascular drugs, antihistamines, tranquillisers/sedatives and gastrointestinal drugs. Conclusions: Users of many common medication categories display significantly reduced unstimulated and/or stimulated salivary flow rate from the major salivary glands compared with non‐users. A larger number of medication categories are associated with reductions in salivary flow rate from submandibular/sublingual glands than parotid glands.     

Radioisotopic and biochemical determination of salivary secretion after long term psychotropic therapy

The aim of this work was to investigate the effect of prolonged psychotropic therapy (neuroleptics and antidepressants over 5 yr on salivary secretion. The flow rate in the parotid and submandibular glands were measured separately by scintigraphy. Flow rates, total protein concentration and total IgA level were determined in the unstimulated saliva in 30 control subjects and 73 patients treated with psychotropic drugs. As evidenced by measurement of flow rates and scintigraphy, psychotropic therapy reduced the unstimulated salivary secretion from parotid glands and to a lesser extent from submandibular gland. The scintigraphic study showed a lower response to stimulation in patients than controls.     

Identification of aquaporin-5 and lipid rafts in human resting saliva and their release into cevimeline-stimulated saliva

BACKGROUND: It is unknown whether AQP5 and lipid rafts are released into human unstimulated (resting) saliva and saliva in response to secretagogues. METHODS: In order to quantitate the salivary concentration of AQP5, we produced a polyclonal antibody for human AQP5 and developed an enzyme-like immunosorbent assay (ELISA). RESULTS: AQP5 and lipid rafts were identified in human resting saliva. The amount of AQP5 in resting saliva showed a diurnal variation with high levels during waking hours, and an age-related decrease in AQP5 was coincident with the volume of resting saliva. Cevimeline, a muscarinic acetylcholine receptor (mAChR) agonist, induced the release of AQP5 with lipid rafts, amylase, mucin, and lysozyme. Changes in saliva AQP5 levels after cevimeline administration occurred simultaneously with changes in saliva flow rates. Confocal microscopy revealed that AQP5 was located in the apical plasma membrane and showed a diffuse pattern in parotid glands under resting conditions. Following cevimeline administration, AQP5 was predominantly associated with the APM and was localized in the lumen. GENERAL SIGNIFICANCE: AQP5 and lipid rafts were released with salivary proteins from human salivary glands by the stimulation of M3 mAChRs, and that changes in saliva AQP5 levels can be used as an indicator of salivary flow rate and also as a useful index of M3 mAChR agonist's action on human salivary glands.     

Regulation mode of evaporative cooling underlying a strategy of the heat-tolerant FOK rat for enduring ambient heat

Compared with other rat strains, the inbred FOK rat is extremely heat tolerant. This increased heat tolerance is due largely to the animal's enhanced saliva spreading abilities. The aims of the present study were to 1) quantify the heat tolerance capacity of FOK rats and 2) determine the regulatory mode of the enhanced salivary cooling in these animals. Various strains of rats were acutely exposed to heat. In the heat-intolerant strains, saliva spreading was insufficient and the core temperature (Tc) rose rapidly. In contrast, FOK rats maintained an elevated Tc plateau (39.5 +/- 0.7 degrees C) for 5-6 h over a wide range of ambient temperatures (Ta) (37.5-42.5 degrees C). In hot environments the FOK rats secreted copious amounts of saliva and spread it over more than the entire ventral body surface. FOK rats had a low Tc threshold for salivation, and the salivation rate increased linearly in proportion to the Tc deviation from the threshold. No strain difference or temperature effect was observed in the saliva secretion rate from in vitro submandibular glands perfused by sufficient doses of ACh. These results suggest that 1) the ability of FOK rats to maintain a moderate steady-state hyperthermia (39.5 +/- 0.7 degrees C) over a wide Ta range is enabled by a lowered threshold Tc for salivation and functional negative-feedback control of saliva secretion and 2) strain differences in ability to endure heat stress are mainly attributable to changes in the thermoregulatory control system rather than altered secretory abilities of the salivary glands.     

Vasoactive intestinal polypeptide and acetylcholine stimulate exocrine secretion of epidermal growth factor from the rat submandibular gland

The effect of vasoactive intestinal polypeptide (VIP) and acetylcholine on secretion of epidermal growth factor (EGF) from the rat salivary glands was investigated. VIP in doses of 3 X 10(-10) to 3 X 10(-8) mol/kg per h stimulated secretion of saliva and total output of EGF dose-dependently. Acetylcholine also stimulated salivation and output of EGF. VIP in a dose of 3 X 10(-11) to 3 X 10(-10) mol/kg per h enhanced the stimulatory effect of acetylcholine, but this effect disappeared when the dose of VIP was increased. Adrenalectomy decreased acetylcholine stimulated total output of EGF by approximately 50%, but only by 20% when acetylcholine plus VIP was administered. EGF was localized to the convoluted granular tubules in the submandibular gland, whereas EGF could not be detected in the remaining salivary glands. The results suggest that VIP and acetylcholine cooperate in the control of exocrine secretion from the rat salivary glands. The effect of acetylcholine, however, seems to be partly dependent on circulating catecholamines.     

Mapping Relative Differences in Human Salivary Gland Secretions by Dried Saliva Spot Sampling and nanoLC–MS/MS

Dried saliva spot sampling is a minimally invasive technique for the spatial mapping of salivary protein distribution in the oral cavity. In conjunction with untargeted nano‐flow liquid chromatography tandem mass spectrometry (nanoLC–MS/MS) analysis, DSS is used to compare the proteomes secreted by unstimulated parotid and submandibular/sublingual salivary glands. Two hundred and twenty proteins show a statistically significant association with parotid gland secretion, while 30 proteins are at least tenfold more abundant in the submandibular/sublingual glands. Protein identifications and label‐free quantifications are highly reproducible across the paired glands on three consecutive days, enabling to establish the core proteome of glandular secretions categorized into eight salivary protein groups according to their biological functions. The data suggest that the relative contributions of the salivary glands fine‐tune the biological activity of human saliva via medium‐abundant proteins. A number of biomarker candidates for Sjögren's syndrome are observed among the gland‐specifically expressed proteins, which indicates that glandular origin is an important factor to consider in salivary biomarker discovery.     

Salivation pattern of Rhodnius prolixus (Reduviidae; Triatominae) in mouse skin

The objective of this work was to study the pattern of salivation of triatomines during feeding in mouse skin. Rhodnius prolixus was fed with a solution of the dye acridine orange or fluorescein. The saliva was efficiently labelled with acridine orange, probably due to the difference in pH between the salivary gland (6.0) and the hemolymph (6.5-7.0). This procedure was not effective at labelling the saliva of Triatoma infestans, however, fluorescent labelling of R. prolixus saliva allowed us to demonstrate that salivation occurs during entire feeding process. The saliva is released soon after the bite. In the probing phase, saliva is pumped continuously in the host skin, including around the blood vessels. During the engorgement phase, saliva is observed in a bolus within the blood vessel and some of it is sucked up by the insect, together with blood. The frequency of saliva emission inside the vessels was low (0.51+/-0.18 Hz). The saliva deposition in the microcirculation is continuous and modulated by the frequency of the cibarial pump because, when functioning at high frequency, cibarial pump sucks almost all saliva to the insect gut. This mechanism would determine the quantity of saliva deposited in the microcirculation as necessary, and consequently minimizing the host's immune response to salivary antigens.     

Chemical characterization of the two forms of epidermal growth factor in murine saliva

Extracts of murine salivary glands contain two molecular forms of epidermal growth factor, EGF I and EGF II (Petrides, P.E., Levine, A.E., Shooter, E.M. in: Peptides: - Synthesis, Structure and Function (Rich, D.H., Gross, E.eds.) p. 781 (1981]. We have identified both molecules not only in salivary gland extracts but also in saliva using only reverse phase liquid chromatography methodology. EGF I and II were isolated from submaxillary gland extracts in a ratio of 3:1 regardless of whether the classical isolation procedure or our rapid RPLC based technique was used. Both molecular forms were present in the same ratio in saliva of mice of both sexes when salivation was induced by epinephrine treatment of the animals. As judged by amino acid analysis and N-terminal sequencing salivary EGF I corresponds to the 53 amino acid sequence of murine EGF and EGF II is Des-ASN-EGF. The observation that EGF and Des-ASN-EGF are consecreted into saliva upon epinephrine stimulation implies a physiological role of EGF II which may be related to the high molecular weight EGF-complex.     

Relationship between canine mucosal and serum immunoglobulin A (IgA) concentrations: serum IgA does not assess duodenal secretory IgA

A double-sandwich enzyme immunoassay method was developed for determination of serum immunoglobulin A (S-IgA) and mucosal secretory immunoglobulin A (sIgA) in duodenal brush samples obtained via endoscopy and the relationship between enteric mucosal sIgA, salivary sIgA and S-IgA in dogs was examined. Twenty healthy dogs underwent routine endoscopy. A brush sample from the duodenal mucosa was obtained and washed in PBS, with a serum sample being taken concurrently. A saliva sample was collected from twelve of these dogs. S-IgA and sIgA with total protein concentrations in the duodenal washings and saliva samples were determined. A significant negative correlation (r = -0.64, P = 0.0059) was found between duodenal sIgA/protein ratios and S-IgA concentrations. Saliva sIgA/protein ratios did not correlate with sIgA/protein ratios of duodenal samples. The method described here allows for direct assessment of duodenal IgA; therefore indirect measures based on serum IgA or salivary IgA can be avoided. In addition, these indirect measures appear to be poor indicators of duodenal sIgA competence in dogs.     

CCL28 has dual roles in mucosal immunity as a chemokine with broad-spectrum antimicrobial activity

CCL28 is a CC chemokine signaling via CCR10 and CCR3 that is selectively expressed in certain mucosal tissues such as exocrine glands, trachea, and colon. Notably, these tissues commonly secrete low-salt fluids. RT-PCR analysis demonstrated that salivary glands expressed CCL28 mRNA at the highest levels among various mouse tissues. Single cells prepared from mouse parotid glands indeed contained a major fraction of CD3(-)B220(low) cells that expressed CCR10 at high levels and CCR3 at low levels and responded to CCL28 in chemotaxis assays. Morphologically, these cells are typical plasma cells. By immunohistochemistry, acinar epithelial cells in human and mouse salivary glands were strongly positive for CCL28. Furthermore, human saliva and milk were found to contain CCL28 at high concentrations. Moreover, the C terminus of human CCL28 has a significant sequence similarity to histatin-5, a histidine-rich candidacidal peptide in human saliva. Subsequently, we demonstrated that human and mouse CCL28 had a potent antimicrobial activity against Candida albicans, Gram-negative bacteria, and Gram-positive bacteria. The C-terminal 28-aa peptide of human CCL28 also displayed a selective candidacidal activity. In contrast, CCL27, which is most similar to CCL28 and shares CCR10, showed no such potent antimicrobial activity. Like most other antimicrobial peptides, CCL28 exerted its antimicrobial activity in low-salt conditions and rapidly induced membrane permeability in target microbes. Collectively, CCL28 may play dual roles in mucosal immunity as a chemoattractant for cells expressing CCR10 and/or CCR3 such as plasma cells and also as a broad-spectrum antimicrobial protein secreted into low-salt body fluids.     

Interactions between developing nerves and salivary glands

Our aim is to provide a summary of the field of salivary gland development and regeneration from the perspective of what is known about the function of nerves during these processes. The primary function of adult salivary glands is to produce and secrete saliva. Neuronal control of adult salivary gland function has been a focus of research ever since Pavlov’s seminal experiments on salivation in dogs. Less is known about salivary gland innervation during development and how the developing nerves influence gland organogenesis and regeneration. Here, we will review what is known about the communication between the autonomic nervous system and the epithelium of the salivary glands during organogenesis. An important emerging theme is the instructive role of the nervous system on the epithelial stem/progenitor cells during development as well as regeneration after damage. We will provide a brief overview of the neuroanatomy of the salivary glands and discuss recent literature that begins to integrate neurobiology with epithelial organogenesis, which may provide paradigms for exploring these interactions in other organ systems.     

Nitric oxide synthase and cGMP activity in the salivary glands of the American dog tick Dermacentor variabilis

We colocalized nitric oxide synthase (NOS) activity in epithelial cells that surround the salivary gland duct in female Dermacentor variabilis with NADPH diaphorase histochemistry and immunohistochemistry using a polyclonal anti-endothelial NOS. Using size-exclusion chromatography, a fraction with a molecular mass of about 185 kDa that had diaphorase activity was eluted from tick salivary gland homogenate. This fraction converted arginine to citrulline with the production of nitric oxide (NO), which was detected by using electron spin resonance spectroscopy. The complete activity of the diaphorase fraction was dependent on NADPH, FAD, tetrahydrobiopterin, calmodulin, (CaM), and Ca(2+), but was not dependent on dithiothreitol. The arginine analog N(G)-monomethyl-L-arginine inhibited the activity of this fraction. NO and arginine activated soluble guanylate cyclase to produce cGMP in dopamine-stimulated isolated salivary glands. Dopamine-stimulated isolated salivary glands treated with tick saline containing either EDTA, the NOS inhibitor N(G)-nitro-L-arginine methyl ester, or the calcium/CaM binding inhibitor W-7 showed no increase in cGMP. The NO donor sodium nitroprusside significantly increased cGMP levels in unstimulated isolated salivary glands. A possible function for NO in salivation by this ixodid tick is discussed.     

Salivary tests associated with elderly people’s oral health

doi: 10.1111/j.1741‐2358.2012.00627.x Salivary tests associated with elderly people’s oral health Introduction: The saliva constitutes essential condition for the individual’s health. Aim: Identify the relation of the salivary flow and saliva pH with medicine use and oral discomfort in elderly. Methods and materials: Cross‐sectional study with 68 elderly living in a long staying institution. Salivary tests were performed based on Bo Krasse’s methodology. For pH, the Universalindikator – Merck tape was used. A questionnaire was applied, organising data through Software SPSS version 17. Pearson’s qui‐square distribution, Fisher’s exact test and t‐test for paired data were used, with significance level of 5% and confidence interval of 95%. Results: Among the 68 elderly (average of 70.4 years, SD ± 7.27), 80% showed normal pH. The rate of salivary flow was as follows: very low, 32.3%; lowered, 41.2%; and normal, 25.5%; 30.9% reported dry mouth; 22.1% problems with taste; 17.6%, dysphagia; and 14.7%, burning mouth. 76.5% used medicines. There was statistical significance between medicine use and dry mouth (p = 0.015). They showed an association between salivary flow and medicine use (p = 0.048), feels dry mouth (0.018) and difficulty to swallow (p = 0.046), and saliva pH without stimulation and feels dry mouth (p = 0.003), difficulty to swallow (p = 0.006) and burning mouth sensation (p = 0.014). Conclusion: Low salivary flow and saliva pH interfere on elderly people’s health and medicine use influences on results.     

Possible role of nitric oxide in radiation-induced salivary gland dysfunction

In this study, we developed a murine model of xerostomia to elucidate the mechanism of radiation-induced salivary gland dysfunction and determined the levels of nitric oxide (NO) in the salivary glands to assess its involvement in the salivary dysfunction induced by radiation. In addition, an inhibitor of NO synthesis was administered to the model in vivo, and its effect on saliva secretion was investigated. Salivary gland irradiation at a dose of 15 Gy caused a significant decrease in secretion compared to unirradiated salivary glands. There were no marked differences between the irradiated mice and unirradiated mice in water or food consumption or in body weight changes. The NO levels in the cultured salivary gland epithelial cells were increased by treatment with a combination of interferon gamma (Ifng), interleukin 1-beta (Il1b), and tumor necrosis factor alpha (Tnfa). Irradiation increased the NO level in the salivary gland tissue. The presence of N(G)-monomethyl-l-arginine acetate (l-NMMA), an inhibitor of NO synthesis, caused a decrease in the NO level in cultured salivary gland tissues after irradiation. Administration of l-NMMA to irradiated mice improved saliva secretion. These results suggest that excessive production of NO induced by radiation is involved in the formation of radiation-induced xerostomia. The finding that administration of an inhibitor of NO synthesis ameliorated the dysfunction of irradiated salivary glands indicates that NO plays a role as a mediator of the dry mouth symptoms that occur after irradiation.     

一种收集蜱类唾液的方法

建立了一种收集蜱类唾液的方法。注射多巴胺(20mgmL)10μL于森林革蜱DermacentorsilvarumOlenev吸血雌蜱血腔内,可使唾液腺分泌唾液,用毛细管连续收集30min,可得唾液15～20μL蜱。     

Pavlov's cockroach: classical conditioning of salivation in an insect

Secretion of saliva to aid swallowing and digestion is an important physiological function found in many vertebrates and invertebrates. Pavlov reported classical conditioning of salivation in dogs a century ago. Conditioning of salivation, however, has been so far reported only in dogs and humans, and its underlying neural mechanisms remain elusive because of the complexity of the mammalian brain. We previously reported that, in cockroaches Periplaneta americana, salivary neurons that control salivation exhibited increased responses to an odor after conditioning trials in which the odor was paired with sucrose solution. However, no direct evidence of conditioning of salivation was obtained. In this study, we investigated the effects of conditioning trials on the level of salivation. Untrained cockroaches exhibited salivary responses to sucrose solution applied to the mouth but not to peppermint or vanilla odor applied to an antenna. After differential conditioning trials in which an odor was paired with sucrose solution and another odor was presented without pairing with sucrose solution, sucrose-associated odor induced an increase in the level of salivation, but the odor presented alone did not. The conditioning effect lasted for one day after conditioning trials. This study demonstrates, for the first time, classical conditioning of salivation in species other than dogs and humans, thereby providing the first evidence of sophisticated neural control of autonomic function in insects. The results provide a useful model system for studying cellular basis of conditioning of salivation in the simpler nervous system of insects.     

Origin, structure, and biological activities of peroxidases in human saliva

Human whole saliva contains two peroxidases, salivary peroxidase (hSPO) and myeloperoxidase (hMPO), which are part of the innate host defence in oral cavity. Both hSPO as well as human milk lactoperoxidase (hLPO) are coded by the same gene, but to what extent the different producing glands, salivary and mammary glands, affect the final conformation of the enzymes is not known. In human saliva the major function of hSPO and hMPO is to catalyze the oxidation of thiocyanate (SCN(-)) in the presence of hydrogen peroxide (H(2)O(2)) resulting in end products of wide antimicrobial potential. In addition cytotoxic H(2)O(2) is degraded. Similar peroxidation reactions inactivate some mutagenic and carcinogenic compounds, which suggests another protective mechanism of peroxidases in human saliva. Although being target of an active antimicrobial research, the structure-function relationships of hSPO are poorly known. However, recently published method for recombinant hSPO production offers new tools for those investigations.