Enhancement of salivary esophagoprotection: Rationale for a physiological approach to gastroesophageal reflux disease

Background & Aims: Secretion of salivary protective factors in patients with gastroesophageal reflux disease is impaired. However, the impact of physiological stimulus mastication on salivary protective factors output remains largely unknown. The aim of this study was to measure salivary volume, pH, HCO3-, peptide growth factors, prostaglandin, mucin, protein, and viscosity during mastication. Methods: In 31 asymptomatic volunteers and 36 patients with endoscopic reflux esophagitis, in basal and parafilm chewing-stimulated saliva, its volume, pH, bicarbonate, epidermal growth factor, transforming growth factor alpha, prostaglandin E(2), mucin, protein, and viscosity were investigated. Results: Masticatory stimulation in controls resulted in a significantly increased salivary volume by 205%, pH by 7.6%, bicarbonate by 335%, mucin by 137%, protein by 98%, epidermal growth factor by 123%, and prostaglandin E(2) by 132%, accompanied by an increase in transforming growth factor a by 80% with 19% decline in viscosity vs. basal values. Mastication in reflux esophagitis significantly increased salivary volume by 215%, pH by 6.8%, bicarbonate by 257%, mucin by 135%, protein by 94%, epidermal growth factor by 207%, and prostaglandin E(2) by 240%, whereas transforming growth factor a increased by 225% and viscosity by 64% when compared with corresponding basal values. Conclusions: A profound and significant increase in the secretion rate of inorganic and organic protective components in saliva during masticatory stimulation suggests its potential value as a therapeutic approach to the treatment of patients with gastroesophageal reflux disease.