Saliva and esophageal protection

Association between masticatory dysfunction and gastroesophageal reflux disease: A population-based study in the elderly

BACKGROUND

Caries and periodontal disease may cause tooth losses and chewing difficulty, especially in the elderly. Ingesting poorly chewed food may delay gastric emptying and favour the development of gastroesophageal reflux disease (GERD).

OBJECTIVE

This study investigated the association between masticatory dysfunction and GERD in the elderly from a rural area in southern Brazil.

METHODS

This census invited all 489 elderly from a city to participate. The study used a GERD symptoms questionnaire, followed by an oral examination. Masticatory dysfunction was analysed based on the chewing difficulty for some food groups. Tooth loss and chewing self-perception were also considered as exposure variables. Poisson regression determined the association among variables by calculating the prevalence ratio [PR (95% confidence interval)].

RESULTS

The response rate was 93.1% (n = 455, average age of 70.9 years, 50.5% men). The prevalence of GERD in this population was 36.9%. GERD was associated with chewing difficulty for vegetables (PR = 1.54), meats (PR = 1.34) and cereals (PR = 1.43) but not with poor chewing self-perception (PR = 0.80) and tooth loss (PR = 1.22). GERD was also associated with xerostomia (PR = 1.63) and the female gender (PR = 1.35).

CONCLUSION

Elderly people from a rural area with a reduced number of teeth present chewing difficulty and a high prevalence of GERD, indicating an association between GERD and masticatory dysfunction.

(Patho-)Physiology of Na+/H+ Exchangers (NHEs) in the Digestive System

Na⁺/H⁺ exchangers (NHEs) are expressed in virtually all human tissues and organs. Two major tasks of those NHE isoforms that are located in plasma membranes are cell volume control by Na⁺-uptake and cellular pH regulation by H⁺-extrusion. Several NHEs, particularly NHE 1–4 and 8, are involved in the pathogenesis of diseases of the digestive system such as inflammatory bowel disease (ulcerative colitis, Crohn’s disease) and gastric and colorectal tumorigenesis. In the present review, we describe the physiological purposes, possible malfunctions and pathophysiological effects of the different NHE isoforms along the alimentary canal from esophagus to colon, including pancreas, liver and gallbladder. Particular attention is paid to the functions of NHEs in injury repair and to the role of NHE1 in Barrett’s esophagus. The impact of NHEs on gut microbiota and intestinal mucosal integrity is also dealt with. As the hitherto existing findings are not always consistent, sometimes even controversial, they are compared and critically discussed.

Salivary functions in mastication, taste and textural perception, swallowing and initial digestion

Saliva exerts multiple functions in relation to the initial digestive processes taking place in the upper parts of the gastrointestinal tract. Ingestion of food and beverages, in turn, is a strong stimulus for secretion of saliva with a differential composition depending on the neuronal stimulation pattern. This review paper provides insight into the mechanisms by which saliva acts in relation to taste, mastication, bolus formation, enzymatic digestion and swallowing. Also, the protective functions of saliva including maintenance of dental and mucosal integrity will be discussed as they indirectly influence the digestive process. The final part of this study focuses on the implications of xerostomia and salivary gland dysfunction on gastrointestinal functions.

Salivary epidermal growth factor concentrations in patients with Sjögren syndrome and laryngopharyngeal reflux

Sjögren syndrome was chosen as a clinical model to study acinar salivary deficiencies in the development of laryngopharyngeal reflux (LPR). The objective of this prospective cohort study was to compare salivary epidermal growth factor (EGF) concentrations of patients with Sjögren syndrome with and without LPR and gastroesophageal reflux disease (GERD) with normal controls. LPR was diagnosed with positive scores on the Reflux Symptom Index and Reflux and Reflux Finding Score, corroborated by esophagogastroduodenoscopy and/or 24-hour pH-metry. Salivary EGF concentrations of both unstimulated and mechanically stimulated saliva were established using enzyme-linked immunosorbent assay, and the significance level was set at 95%. Twenty-one patients and 19 controls were studied. All patients had LPR and 60% also had GERD. The mean salivary EGF concentration of unstimulated and stimulated saliva in the control group was 1,751.37 pg/ml and 544.76 pg/ml, respectively. Unstimulated and stimulated salivary EGF concentrations in the study group were 2,534.65 pg/ml and 920.69 pg/ml, respectively. These differences were not statistically significant. Body mass index, presence of erosive esophagitis, or severity of hyposalivation did not significantly influence salivary EGF concentrations. LPR and GERD are highly prevalent in patients with Sjögren syndrome. Unlike previous studies in which significant EGF deficiencies were found in patients with reflux laryngitis and GERD, patients with Sjögren syndrome seem to have reflux caused by a decrease in clearance capacity and not in specific salivary components.

The ontogeny of saliva secretion in infants and esophagoprotection

BACKGROUND

Several studies have reported that severe reflux esophagitis is rare in infants despite the well known high occurrence of regurgitation in early infancy. There is evidence of the importance of saliva for the pre-epithelial protection of the esophageal mucosa.

RESULTS

A longitudinal study conducted on healthy infants indicated that the stimulated capacity of saliva secretion (saliva output per kg of body weight) was significantly higher during their first year of age compared to older children and adults. In addition, this secretion pattern was also observed in low weight newborns during the first weeks of life and persisted in infants with severe protein-calorie malnutrition (marasmus).

CONCLUSION

The greater ability to secrete saliva is an important physiological condition that may protect the infant from acid/pepsin aggression to the esophagus during early stages of development.

Salivary transforming growth factor alpha in patients with Sjögren's syndrome and reflux laryngitis

Introduction

Saliva plays a key role in the homeostasis of the digestive tract, through its inorganic components and its protein growth factors. Sjögren's syndrome patients have a higher prevalence of gastroesophageal reflux disease and laryngopharyngeal reflux. Decreased salivary transforming growth factor alpha levels were observed in dyspeptic patients, but there have been no studies in patients with Sjögren's syndrome and laryngopharyngeal reflux.

Objective

To compare the salivary transforming growth factor alpha levels of patients with Sjögren's syndrome and laryngopharyngeal reflux to those of healthy controls.

Methods

This is a prospective controlled study. Twelve patients with Sjögren's syndrome and laryngopharyngeal reflux and 11 controls were prospectively evaluated. Spontaneous and stimulated saliva samples were obtained to establish salivary transforming growth factor alpha concentrations.

Results

The salivary transforming growth factor alpha levels of patients were significantly higher than those of healthy controls. Five patients with laryngopharyngeal reflux also had erosive esophagitis; their salivary transforming growth factor alpha levels were comparable to controls.

Conclusion

Salivary transforming growth factor alpha level was significantly higher in patients with Sjögren's syndrome and laryngopharyngeal reflux when compared to the control group.

Salivary gland enlargement and sialorrhoea in dogs with spirocercosis: a retrospective and prospective study of 298 cases

This longitudinal cross-sectional clinical study investigated the incidence of sialorrhoea in dogs with spirocercosis and determined whether breed, body weight and the extent of the oesophageal involvement was associated with this presentation. A retrospective analysis was performed on the medical records of 233 dogs and information pertaining to 65 dogs was collected as part of a prospective study. All the animals were client-owned. Patients from the retrospective study underwent thoracic radiography or oesophageal endoscopy to diagnose and characterise the infection and were placed on therapy with a macrocyclic lactone, whereas the patients in the prospective study had both radiography and endoscopy routinely performed and biopsies of the oesophageal nodules collected where possible. Tru-cut biopsies of affected salivary glands were taken in 10 of 13 patients demonstrating clinical signs of sialorrhoea and salivary gland enlargement. The entire salivary gland was sectioned in an additional three dogs with spirocercosis and no sialorrhoea that were presented for post mortem examination. Sialorrhoea was present in 33/298 cases (11%). Fox terrier breeds were over-represented in the patients with sialorrhoea, comprising 36% of cases, whereas they only comprised 1.5% of the patients without sialorrhoea (p < 0.001, chi squared test) and 5% of the combined group. Dogs weighing 12 kg or less were significantly over-represented in the sialorrhoea group, 69% versus 19.5% (p < 0.001, chi square test). Age was not significantly different between the two groups (p < 0.08, Mann-Whitney test). The number of oesophageal nodules per case was significantly higher in the non-sialorrhoea cases (p = 0.048, Mann-Whitney test). The prevalence of distal oesophageal and lower oesophageal sphincter involvement, and neoplastic transformation of the nodules were not statistically different between the two groups. None of the fox terriers in either group showed neoplastic transformation of the parasitic nodules even though they were over-represented as a breed. Mandibular salivary glands were affected in 86% of cases showing sialorrhoea. Histopathology revealed acinar hyperplasia in all cases with concurrent necrosis detected in only two cases.Sialorrhoea and salivary gland enlargement has an incidence of 11% (33/298 cases) in canine spirocercosis. Small breeds (≤ 12 kg) and particularly fox terrier breeds are over-represented in the group demonstrating sialorrhoea and this appeared to be the only risk factor.The conclusion was that sialorrhoea secondary to canine spirocercosis occurs frequently and its presence should prompt further investigation for oesophageal and gastro-intestinal disease. Severely affected patients can be managed with phenobarbitone to control the dysphagia in addition to the routine macrocyclic lactones treatment.

Science behind human saliva

Saliva is a complex fluid, which influences oral health through specific and nonspecific physical and chemical properties. The importance of saliva in our everyday activities and the medicinal properties it possesses are often taken for granted. However, when disruptions in the quality or quantity of saliva do occur in an individual, it is likely that he or she will experience detrimental effects on oral and systemic health. Often head and neck radiotherapy has serious and detrimental side effects on the oral cavity including the loss of salivary gland function and a persistent complaint of a dry mouth (xerostomia). Thus, saliva has a myriad of beneficial functions that are essential to our well-being. Although saliva has been extensively investigated as a medium, few laboratories have studied saliva in the context of its role in maintaining oral and general health.

Salivary cytokines in cell proliferation and cancer

While the presence of multiple systemic steroids, amines and peptides in saliva has been reported, other hormones of the circulation do not appear in saliva. Substances present within saliva may be classified in different groups: first, those which passively display blood plasma concentrations and constitute a promising alternative to evaluate certain systemic parameters. Second, molecules which seem to play a more active, regulatory role within the upper gastrointestinal tract. Concerning the latter, a growing awareness, especially with regards to salivary peptides has been established. Up to now, understanding the distinct effects of salivary peptides known so far is in its infancy. Various publications, however, emphasize important effects of their presence. Salivary peptides can influence inflammatory processes and cell proliferation in epithelia of the upper digestive tract. These include transforming growth factors (TGFs), epidermal growth factors (EGFs), vascular endothelial growth factors (VEGFs) as well as amines such as melatonin. Of those, candidate cytokines like interleukin 8, tumor necrosis factors (TNFs) and leptin are involved in neoplastic activities of salivary glands and the oral cavity. The exact mechanisms of action are not yet completely understood, but their presence can be utilized for diagnostic purposes. Salivary gland tumors in patients may, in certain circumstances, be identified by saliva diagnostics. Saliva samples of the concerned patients, for instance, reveal significantly higher leptin concentrations than those of healthy individuals. Numerous studies postulate that, beside single indicators, the establishment of salivary hormone profiles may assist clinicians and researchers in detecting tumors and other pathologies of the oral cavity, including adjacent tissues, with high sensitivity and specificity.

Loss of alkalization in proximal esophagus: a new diagnostic paradigm for patients with laryngopharyngeal reflux

INTRODUCTION

Cervical esophageal pH monitoring using a pH threshold of <4 in the diagnosis of laryngopharyngeal reflux (LPR) is disappointing. We hypothesized that failure to maintain adequate alkalization instead of acidification of the cervical esophagus may be a better indicator of cervical esophageal exposure to gastric juice. The aim of this study was to define normal values for the percent time the cervical esophagus is exposed to a pH ≥7 and to use the inability to maintain this as an indicator for diagnosis of LPR.

MATERIAL AND METHODS

Fifty-nine asymptomatic volunteers had a complete foregut evaluation including pH monitoring of the cervical esophagus. Cervical esophageal exposure to a pH <4 was calculated, and the records were reanalyzed using the threshold pH ≥7. The sensitivity of these two pH thresholds was compared in a group of 51 patients with LPR symptoms that were completely relieved after an antireflux operation.

RESULTS

Compared to normal subjects, patients with LPR were less able to maintain an alkaline pH in the cervical esophagus, as expressed by a lower median percent time pH ≥ 7 (10.4 vs. 38.2, p < 0.0001). In normal subjects, the fifth percentile value for percent time pH ≥ 7 in the cervical esophagus was 19.6%. In 84% of the LPR patients (43/51), the percent time pH ≥ 7 were below the threshold of 19.6%. In contrast, 69% (35/51) had an abnormal test when the pH records were analyzed using the percent time pH < 4. Of the 16 patients with a false negative test using pH < 4, 11 (69%) were identified as having an abnormal study when the threshold of pH ≥ 7 was used.

CONCLUSION

Normal subjects should have a pH ≥7 in cervical esophagus for at least 19.6% of the monitored period. Failure to maintain this alkaline environment is a more sensitive indicator in the diagnosis of the LPR and identifies two thirds of the patients with a false negative test using pH <4.

Modulation of salivation and heartburn in response to the site of acid infusion in the human oesophagus

BACKGROUND

The pathogenesis of gastro-oesophageal reflux disease includes increased acid reflux, reduced salivation and impaired peristalsis. This may depend upon the height of acid wave and magnitude of oesophageal mucosal exposure. Interestingly, the effect of site of acid infusion upon salivary secretion and heartburn has not been examined in any detail.

AIM

To examine whether acid infusion in the upper oesophagus may cause increased salivation and heartburn as compared with acid infusion in the lower oesophagus.

METHODS

Twelve healthy male subjects (mean age 30) received infusions of HCl, citric acid and acetic acid at 10 and 20 cm above the lower oesophageal sphincter (LES) for fixed time periods. Parotid saliva collected periodically and heartburn severity scored using standardized scale. Standard statistical methods (paired t-tests, analysis of variance) were used to determine the significance of results.

RESULTS

Acid infusion in the upper oesophagus increased parotid flow rate as compared with that in the lower oesophagus (P < 0.05). Likewise, there was a significantly increased heartburn score at 20 cm as well as 10 cm above LES (P < 0.05) as compared with that in the stomach.

CONCLUSION

These data suggest a significant increase in salivation and heartburn in response to acid infusion in the upper vs. lower part of the oesophagus.

Premastication: the second arm of infant and young child feeding for health and survival?

Premastication of foods for infants was a crucial behavioural adaptation to neoteny that ensured nutritional adequacy during the period of complementary feeding throughout the course of human evolution until recent times.While the paps and gruels of agricultural systems provided an alternative and modern food technology appears to make it unnecessary, we argue that, in addition to its role in nutrition, premastication also played a crucial role in supporting infant health. Its abandonment, particularly in poor communities, has placed children at increased risk of inadequate nutrition and decreased ability to confront infections associated with the introduction of complementary foods.We present two empirical studies. Section I is a cross-cultural study of the ethnographic literature in order to estimate prevalence in non-Western societies.One-third of ethnographies in the worldwide sample with data on infant feeding report premastication. Section II presents the results of a qualitative study in China, conducted in order to provide data on the likelihood that this percent is incorrect due to under-reporting.The finding that 63% of Chinese university students received premasticated food as infants, whereas none of eight ethnographic studies performed in Han China identified premastication in their reports, provides support for the conclusion that the cross-cultural study grossly underestimates its prevalence in non-Western societies. Section III is a discussion of potential benefits and risks of infant exposure to maternal saliva.We conclude with the argument for a concerted research effort to determine whether premastication can solve not only the 'weanling dilemma' in poor countries but also some of the health problems among the better-off.

The modified glucose clearance test: a novel non-invasive method for differentiating non-erosive reflux disease and erosive oesophagitis

BACKGROUND

Impaired salivary secretion has been reported to cause abnormal acid clearance from the oesophagus in gastro-oesophageal reflux disease (GERD). However, few studies have explained the differences between non-erosive reflux disease (NERD) and erosive oesophagitis (EO) with respect to salivary secretion. Aim To elucidate these differences, we measured salivary secretion by using the modified glucose clearance test (mGCT).

METHODS

All subjects completed endoscopic examinations, the frequency scale for the symptoms of GERD questionnaire and the mGCT comprising a resting GCT (measured as RGC time) and a chewing-stimulated GCT (SGC time).

RESULTS

Resting glucose clearance time was 18.5 min in control group and significantly longer in NERD and EO groups (28.5 and 39.0 min respectively). SGC time was 6.1 min in control group and 7.2 min in NERD group and significantly longer in EO group (10.2 min) than in the control and NERD groups.

CONCLUSIONS

In the EO group, both resting and stimulated salivary secretions were less than in control group. However, in the NERD group, resting salivary secretion was decreased, but stimulated salivary secretion was similar to that of the control group. Therefore, these results may help in explaining the differences in the pathogenesis of NERD and EO.

Saliva variations in gastro-oesophageal reflux disease

OBJECTIVES

The protective role of saliva in the case of oesophageal exposition to gastric acid has long been studied but some contradictions still remain. The main end-point of this study was to evaluate if a qualitative and quantitative alteration in salivary secretion exists in patients affected by GERD.

METHODS

One hundred and twenty patients (T group) with clinically and endoscopically diagnosed GERD, and 98 healthy subjects (C group) have been evaluated; salivary tests (i.e. basal flow rate, stimulated flow rate, pH, [Na(+)] and [K(+)]) were performed, socio-demographical variables and oral GERD-related symptoms were taken into account. SPSS 10.5 software was used for statistical univariate and multivariate analyses.

RESULTS

GERD patients and controls were found to have a similar basal flow rate but different stimulated salivary function [T group mean value 0.989 ml/min (+/-0.48718) vs. C group 1.2197 ml/min (+/-0.6108), pH [T group mean value 8.935 (+/-0.471) vs. C group 7.879 (+/-0.526)] and a higher K(+) concentration. In GERD patients we also registered a significant association with xerostomia [69/120 (57.5%) vs. 28/98 (28.7%)] and an oral burning sensation [58/120 (48.3%) vs. 19/98 (19.3%)].

CONCLUSIONS

Our findings assess that salivary secretion is altered in GERD patients and highlight the need for further investigations in order to define the role of saliva in the etiopathogenesis of GERD.

Gastroesophageal reflux patients' defective antioxidative capacity in the proximal esophageal mucosa before antireflux surgery and also after 4-year follow-up

BACKGROUND

Oxidative stress has a role in the pathogenesis of gastroesophageal reflux disease (GERD).

AIM

To investigate the redox balance in proximal esophagus before and 6 and 48 months after antireflux surgery.

METHODS

In 20 GERD patients and 9 controls oxidative stress by myeloperoxidase activity (MPO activity) and antioxidative capacity of esophageal mucosa by superoxide dismutase activity (SOD), and glutathione content (GSH) was measured from proximal esophageal samples.

RESULTS

In proximal esophagus of GERD patients compared to controls', antioxidative capacity appearing as GSH level was significantly decreased (P < 0.001) at all time points and as SOD levels preoperatively (P < 0.001) and 4 years postoperatively (P = 0.01). MPO activity of patients was significantly lower than controls' preoperatively, and 6 months and 4 years postoperatively (P < 0.05). MPO activity remained lower than that of the distal esophagus at 6 months and 4 years (P < 0.01 for both).

CONCLUSIONS

In GERD patients, proximal esophageal mucosal antioxidative defense is defective before and after antireflux surgery. Antireflux surgery seems not to change the level of oxidative stress in proximal esophagus, suggesting that defective mucosal antioxidative capacity plays a role in development of oxidative damage to the esophageal mucosa in GERD.

Air swallowing, belching, and reflux in patients with gastroesophageal reflux disease

OBJECTIVES

Belching and gastroesophageal reflux share a common physiological mechanism. The aim of this study was to investigate whether air swallowing leads to both belching and reflux.

METHODS

Esophageal impedance, pH, and pressure were measured during two 20-min recording periods in 12 controls and 12 patients with gastroesophageal reflux disease (GERD), before and after intragastric inflation of 600 mL of air. This was repeated after a meal. Subsequently, ambulatory 24-h impedance-pH measurement was performed.

RESULTS

During the 24-h study, patients showed a higher incidence of air swallows (287 +/- 45 vs 176 +/- 24, p < 0.05), belches (52.4 +/- 6.6 vs 32.7, p < 0.01), and acid reflux (42.3 +/- 7.6 vs 19.1 +/- 2.8, p < 0.01) than controls. After air infusion the incidence of gas reflux episodes was increased, both in patients (0.58 +/- 0.36 vs 3.50 +/- 0.61, p < 0.01) and in controls (0.75 +/- 0.67 vs 4.08 +/- 0.59, p < 0.01). In contrast, the incidence of acid and weakly acidic reflux episodes was not increased after air infusion, neither in patients (acid: 1.25 +/- 0.37 vs 1.20 +/- 0.33, weakly acidic: 1.08 +/- 0.40 vs 0.80 +/- 0.23) nor in controls (acid: 0.72 +/- 0.34 vs 0.50 +/- 0.23, weakly acidic: 0.80 +/- 0.35 vs 0.33 +/- 0.19). Air infusion increased transient lower esophageal sphincter relaxations (TLESR) frequency in patients and controls, but this was entirely because of an increase in gas reflux-associated TLESRs.

CONCLUSIONS

Patients with GERD swallow air more frequently and belch more frequently than healthy subjects. However, air swallowing is not the cause of their increase in reflux.

Roles of epidermal growth factor and Na+/H+ exchanger-1 in esophageal epithelial defense against acid-induced injury

Epidermal growth factor (EGF) is predominantly secreted by salivary glands and activates Na(+)/H(+) exchanger-1 (NHE-1), which regulates intracellular pH (pH(i)). We investigated the roles of EGF and NHE-1 in esophageal epithelial defense against acid using human esophageal epithelial cell lines and a rat chronic esophagitis model. Esophageal epithelial cells were incubated with acidified medium in the absence or presence of EGF. Cell viability and changes in pH(i) were measured. Chronic acid reflux esophagitis was induced in rats with and without sialoadenectomy. Esophageal lesion index, epithelial proliferation, and expression of EGF receptors and NHE-1 were examined. EGF protected esophageal epithelial cells against acid in a dose-dependent manner, and the cytoprotective effect of EGF was completely blocked by treatment with NHE-1 inhibitors. Tyrosine kinase, calmodulin, and PKC inhibitors significantly inhibited cytoprotection by EGF, whereas MEK, phosphatidylinositol 3-kinase, and PKA inhibitors had no effect. EGF significantly increased pH(i) recovery after NH(4)Cl pulse acidification, and this increase in pH(i) recovery was significantly blocked by inhibitors of calmodulin and PKC. Sialoadenectomy led to an increase in the severity of chronic esophagitis but affected neither epithelial proliferation nor expression of EGF receptors. Expression of NHE-1 mRNA was increased in esophagitis and upregulated in rats with sialoadenectomy. The increasing severity of esophagitis in rats with sialoadenectomy was prevented by exogenous administration of EGF. In conclusion, EGF protects esophageal epithelial cells against acid through NHE activation via Ca(2+)/calmodulin and the PKC pathway. Deficiency in endogenous EGF is associated with increased severity of esophagitis. EGF and NHE-1 play crucial roles in esophageal epithelial defense against acid.

Estudo comparativo do pH e do volume salivar em indivíduos com laringofaringite crônica por doença do refluxo gastroesofágica antes e após o tratamento

INTRODUÇÃO: A Doença do Refluxo Gastroesofágico (DRGE) é a doença digestiva mais prevalente da atualidade e, recentemente, tem sido implicada em uma gama de alterações do seguimento laringofaríngeo (RLF). No entanto, pouco se sabe dos mecanismos fisiopatológicos destas manifestações supraesofágicas da DRGE. Os achados clínicos contraditórios e recentes pesquisas sugerem haver deficiências na capacidade de defesa deste seguimento. Uma das principais responsáveis pela homeostase da mucosa oral e do trato digestivo é a saliva com seu conteúdo orgânico e inorgânico. Tanto alterações do pH quanto do volume salivar já foram correlacionados com os sintomas e sinais sugestivos da DRGE e RLF. Estudo recente de nossa autoria demonstra diminuição estatisticamente significante do pH salivar de indivíduos com RLF quando comparado a controles sem a doença. Outro estudo constatou correlação entre a redução do volume X pH da saliva em indivíduos com DRGE, estando esta redução diretamente relacionada aos níveis de pH esofágico constatados durante pH-metria esofágica de 24 horas. OBJETIVOS: Avaliar como se comportam o pH e volume da saliva em um mesmo indivíduo com DRGE e RLF antes e após o tratamento clínico. MATERIAL E MÉTODO: Vinte e três pacientes com RLF tiveram o pH e volume da saliva total testados antes e após receberem tratamento com droga bloqueadora de bomba de prótons durante 12 semanas. RESULTADOS: Houve uma diferença estatisticamente significante (p<0,001) entre o pH da saliva antes e após o tratamento, estando este maior após o controle clínico da doença. O volume de saliva no paciente tratado foi significativamente maior do que no paciente pré-tratamento (p=0.009). DISCUSSÃO: Os achados sugerem que o pH salivar é influenciado pela presença de refluxo gastroduodenal à região laringofaríngea. Caso estudos futuros com populações maiores realmente comprovem esta correlação, poderemos cogitar a possibilidade de usar a mensuração do pH salivar, que é feita de forma rápida e não invasiva, como um meio de diagnosticar e avaliar o comportamento e controle do Refluxo Laringofaríngeo.

Comparative study of salivary pH and volume in adults with chronic laryngopharyngitis by gastroesophageal reflux disease before and after treatment

INTRODUCTION

Gastroesophageal Reflux Disease (GERD) is the most prevalent digestive disease of the modern society and has been associated with abnormalities in the larynx and pharynx (LPR). Nonetheless, little is known about the mechanisms involved in this atypical form of the disease. Contradictory clinical data suggest a defense deficit at this segment. Saliva with its organic and inorganic components is responsible for the homeostasis of the oral mucosa and the digestive tract. Salivary pH and volume abnormalities have been linked to laryngopharyngeal symptoms of GERD and LPR. In a recent study we demonstrated significant salivary pH reduction in patients with LPR. Another study found correlation between reduced salivary pH and volume directly related to esophageal pH-metry results.

AIM

To evaluate salivary pH and volume before and after clinical treatment of LPR.

MATERIAL AND METHOD

Twenty-three adults with LPR had total fasting saliva tested before and after a 12-week course of oral proton pump inhibitor.

RESULTS

A statistically significant difference was found in salivary pH before and after treatment with increase of pH values after control of the disease (p<0.001). Salivary volumes of treated patients were also significantly higher than in pre-treated patients (p=0.009).

DISCUSSION

These findings suggest that salivary pH and volume are influenced by the presence of gastroesophageal contents and that salivary pH monitoring can potentially become a cost-effective method for diagnosing and controlling LPR.

Occurrence of peptic ulcer disease in connective tissue disease patients associated with xerostomia

BACKGROUND

Saliva plays a role in mucosal protection and ulcer healing.

AIM

: To study whether decreased salivary production leads to peptic ulcer disease in connective tissue disease patients associated with xerostomia.

PATIENTS AND METHODS

Two hundred and two connective tissue disease patients (90 with xerostomia and 112 without xerostomia) were enrolled. Their demographic data and use of medications were recorded. Peptic ulcer disease was confirmed by endoscopy. The stimulated salivary output and secretory epidermal growth factor level were measured.

RESULTS

Compared with non-xerostomic counterparts, xerostomic patients manifested a higher occurrence of peptic ulcer disease (31% vs. 12%, P = 0.001), lower stimulated salivary output (9.3 +/- 4.1 vs. 22.9 +/- 5.9 mL/15 min, P < 0.001) and lower stimulated salivary epidermal growth factor output (1.40 +/- 0.77 vs. 3.00 +/- 0.96 ng/min, P < 0.001). Multivariate analysis disclosed that an older age (> or = 60 years) (odds ratio, 4.71; P < 0.001), xerostomia with stimulated salivary output of < or =1 mL/min (odds ratio, 7.54; P = 0.014) and the use of non-steroidal anti-inflammatory drugs (odds ratio, 5.76; P = 0.031) were the risk factors leading to peptic ulcer disease. In addition, xerostomic connective tissue disease patients receiving non-steroidal anti-inflammatory drugs manifested an extremely high risk of development of peptic ulcer disease (odds ratio, 19.78; P < 0.001).

CONCLUSIONS

Ageing, the use of non-steroidal anti-inflammatory drugs and poor salivary function are potential risk factors for the development of peptic ulcer disease in patients with connective tissue disease. If these xerostomic subjects consume non-steroidal anti-inflammatory drugs, they will encounter an extremely high peptic ulcer disease risk.

The significance of saliva during sleep and the relevance of oromotor movements

Saliva is an essential component of the oroesophageal milieu and allows for normal speech, taste, mastication, food bolus formation and swallowing. Saliva has important functions in protecting the hard and soft tissues of the oral cavity from acids and pathogenic microbes. A large number of people suffer either subjective or objective alterations in quantity and/or quality of their saliva that may be secondary to disease, medications, medical treatments or emotional events. Sleep-related xerostomia is a sensation of dry mouth associated with a report of either mouth and/or throat discomfort that induces awakenings for water intake. The prevalence of self-reported dry mouth complaint during sleep (associated with awakening and water intake) in a Canadian survey was estimated at 23%. The biological significance of decreased saliva during sleep is unknown and it is unclear how the oral cavity compensates for this period of relative dryness. The amount of saliva produced is greatest during the waking hours of the day and diminishes dramatically during sleep and may represent another process in the human body that displays a circadian rhythmicity. Salivary secretion during wakefulness is, in part, associated with oromotor activity involving the masticatory muscles. Rhythmic masticatory muscle activity and swallowing are non-disruptive events that occur during normal sleep. We hypothesize herein that lubrication from saliva is necessary during sleep to protect tissue integrity and health of oroesophageal structures.

Increased expression of epidermal growth factor receptors in basal cell hyperplasia of the oesophagus after acid reflux oesophagitis in rats

BACKGROUND

Epidermal growth factor (EGF), which binds to EGF receptors (EGF-R), stimulates oesophageal epithelial cell proliferation, enabling rapid repair after mucosal injury. In the normal human oesophageal epithelium, EGF-R expression is present and confined to the basal layer.

AIM

To examine histological changes in and dynamics of EGF-R expression during healing after acid reflux oesophagitis in a rat model.

METHODS

Gastric acid reflux oesophagitis was induced in Wistar rats by ligation of the pylorus and the transitional region between the forestomach and the grandular portion for 5 h, followed by release of both ligations. Rats were killed 7 and 14 days after production of oesophagitis to examine macroscopic and histological changes as well as dynamics of EGF-R expression. Epithelial cell proliferation was assessed by bromodeoxyuridine (BrdU) uptake, and expression of EGF-R mRNA and protein by RT-PCR and Western blotting or immunohistochemistry.

RESULTS

Gastric acid reflux induced erosive and ulcerative mucosal lesions in the lower and middle part of the oesophagus. These lesions were healed by 14 days and histologically showed thickening of the oesophageal epithelium from 41.11 +/- 3.09 microm in controls to 142.73 +/- 11.59 microm (P < 0.001) in ligated rats, as well as elongation of papillae and basal cell hyperplasia. The number of BrdU-positive cells among basal cells on day 14 was significantly increased from 7.1 +/- 0.8/field in controls to 30.9 +/- 3.0/field in ligated rats. Expression of EGF-R mRNA and protein was significantly increased on day 14 and most basal cells were immunohistochemically positive in both BrdU and EGF-R staining.

CONCLUSION

Acid reflux-induced oesophageal injury caused basal cell hyperplasia with an increase in cell proliferation and EGF-R expression. Activation of EGF-R gene and protein in response to acid reflux-induced injury may facilitate mucosal healing. These results suggest that epidermal growth factor receptors play a crucial role in healing after acid reflux oesophagitis in rats.

Secretion by striated ducts of mammalian major salivary glands: review from an ultrastructural, functional, and evolutionary perspective

In addition to their role in electrolyte homeostasis, striated ducts (SDs) in the major salivary glands of many mammalian species engage in secretion of organic products. This phenomenon usually is manifested as the presence of small serous-like secretory granules in the apical cytoplasm of SD cells. The composition of these granules is largely unknown, except in the case of the cat and rat submandibular gland, where the granules have unequivocally been shown to contain kallikrein. In some species, the apical cytoplasm of SD cells contains variable numbers of vesicles, both spherical and elongated, that vary in appearance from 'empty' to moderately dense. In the rat parotid gland, lucent vesicles transport glycoproteins to the luminal surface where they are incorporated into the apical plasmalemma and the glycocalyx. There is a strong possibility that in various species some of these vesicles are involved in transcytosis of antibodies to the saliva from their source (plasma cells) in the surrounding connective tissue. In addition, vesicles may engage in transfer of growth factors from the saliva to the interstitium. In a few species, conventional SDs have been replaced by ducts that are wholly given over to secretion, i.e., they entirely lack basal striations; although such ducts occupy the histological position of conventional SDs, it is not clear whether they represent a new type of duct or merely are modifications of SDs. Broad-based comparisons of ultrastructural and other data about SDs offer some insight into evolutionary history of salivary glands and their role in the adaptive radiation of mammals. Evolutionary patterns emerged when we made interspecific comparisons across mammalian orders. Among the bats, there is a clear relationship between SD secretion and general categories of diet.

Pathogenesis of gastroesophageal reflux and Barrett esophagus

Barrett esophagus is a metaplastic condition that affects the lower esophagus and is a complication of gastroesophageal reflux disease (GERD). Under normal circumstances, the reflux of gastric contents into the esophagus is prevented by a complex barrier at the esophagogastric junction. Dysfunction of the lower esophageal sphincter and the presence of a hiatal hernia lead to failure of this barrier. Esophageal mucosal damage results from the chronic exposure of the esophageal mucosa to gastroduodenal contents and the lack of an effective mucosal defense. This article is an overview of the dysfunction of the esophagogastric junction that leads to GERD. The role of the contents of the reflux and that of Helicobacter pylori infection in the pathogenesis of Barrett esophagus are also summarized.

Pathogenesis of gastroesophageal reflux and Barrett esophagus

Barrett esophagus is a metaplastic condition that affects the lower esophagus and is a complication of gastroesophageal reflux disease (GERD). Under normal circumstances, the reflux of gastric contents into the esophagus is prevented by a complex barrier at the esophagogastric junction. Dysfunction of the lower esophageal sphincter and the presence of a hiatal hernia lead to failure of this barrier. Esophageal mucosal damage results from the chronic exposure of the esophageal mucosa to gastroduodenal contents and the lack of an effective mucosal defense. This article is an overview of the dysfunction of the esophagogastric junction that leads to GERD. The role of the contents of the reflux and that of Helicobacter pylori infection in the pathogenesis of Barrett esophagus are also summarized.