<p>Pump Proton and Laryngeal H⁺/K⁺ ATPases</p>

Abstract

Purpose The presence of extra-gastric H + /K + ATPases may explain the clinically significant effect of proton pump inhibitor (PPI) pharmacotherapy in patients with chronic laryngitis related to laryngopharyngeal reflux disease (LPRD) but without gastroesophageal reflux disease (GERD) symptoms. Given the need for a better understanding of GERD and LPRD, we review the various proton pumps with respect to their classification, function, and distribution. We then consider the potential role of the laryngeal H + /K + ATPase pump in LPRD. Methods We searched databases of PubMed, EMBASE, and Web of Science to achieve related published before September 15, 2020. Results There were only seven English-literatures meeting inclusive criteria about laryngeal H + /K + ATPases. Some studies provide convincing evidence of a laryngeal H + /K + ATPase in normal laryngeal tissues but also suggest the potential role of the proton pump in the abnormal mucus secretion frequently seen in patients with chronic laryngitis. Conclusion A laryngeal H + /K + ATPase expresses in normal laryngeal tissues. These findings question the current understanding of GERD and LPRD.

Pepsin Increases the Proliferation of Vocal Cord Leukoplakia Epithelial Cells by Inducing Autophagy

“…26 Gastric H + /K + -ATPase, a heterodimeric proton pump composed of α and β subunits, secretes gastric acid. 3,13,21,22 Normal laryngeal mucosa expresses H + /K + ATPase. [27][28][29][30] We previously observed the expression of ATP4A and ATP4B in both normal laryngeal tissue and laryngeal carcinoma tissue, 21 similar to findings by McCormick et al 30 The presence of H + /K + ATPase outside the stomach may cause damage to the collecting duct, 31 cochlear lateral wall, 32 and sinonasal epithelial cells through the activation of inflammatory factors.…”

“…Pepsin is derived from pepsinogen, which is exclusively produced in the fundus in the presence of hydrogen chloride 26 . Gastric H + /K + ‐ATPase, a heterodimeric proton pump composed of α and β subunits, secretes gastric acid 3,13,21,22 . Normal laryngeal mucosa expresses H + /K + ATPase 27‐30 .…”

“…Antigen retrieval was conducted in an autoclave for 5 minute, followed by incubation with 3% hydrogen peroxide (H112520; Aladdin) for 20 minutes. Immunohistochemistry was performed to detect pepsin (1:200; DF8591; Affinity Biosciences), ATP4A (1:200; D031‐3; MBL), and ATP4B (1:200; D032‐3; MBL) in laryngeal carcinoma tissue and VCL tissue, as previously described 3,21,22 …”

“…Immunohistochemistry was performed to detect pepsin (1:200; DF8591; Affinity Biosciences), ATP4A (1:200; D031-3; MBL), and ATP4B (1:200; D032-3; MBL) in laryngeal carcinoma tissue and VCL tissue, as previously described. 3,21,22 Primary Culture of Human VCL…”

“…14,15 Previously, we found that both H + /K + ATPase subunits were expressed in normal laryngeal mucosa, VCL cells, and laryngeal carcinoma. 3,21,22 However, it remains unclear whether the effect of H + /K + ATPase on lysosomes alters autophagy flux in laryngeal tissue and VCL tissue; as noted above, the role of autophagy in the proliferation of VCL cells is also unclear.…”