Elucidating functional involvement of transient receptor potential vanilloid 4 (TRPV4) to trigger swallowing reflex

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K21027
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0907:Oral science and related fields
• Research Institution: Matsumoto Dental University
• Principal Investigator: Roy Rita Rani 松本歯科大学, 歯学部, 助教 (70963487)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: Swallowing Reflex / TRPV4

Outline of Final Research Achievements

We investigate the involvement of TRPV4 in initiating the swallowing reflex. Our observations reveal that TRPV4 immunoreactive nerve fibers present in the superior laryngeal nerve (SLN)-innervated swallowing-related regions. Retrograde tracing with fluorogold reveals localization of TRPV4 on approximately 25% of SLN-afferent neurons in the nodose-petrosal-jugular ganglionic complex. Among them, approximately 49% are large, 35% medium, and 15% small-sized SLN-afferent neurons. Furthermore, our investigation demonstrates that the topical administration of a chemical agonists targeting TRPV4, GSK1016790A, in swallowing-related regions, leads to a dose-dependent facilitation of the swallowing reflex. Notably, the preapplication of antagonists for TRPV4 significantly mitigates the GSK1016790A-induced swallowing reflex.
These findings underscore the potential of targeting TRPV4 to develop therapeutics to enhance swallowing function.

Free Research Field

Oral Physiology

Academic Significance and Societal Importance of the Research Achievements

Dysphagia poses a significant health challenge, with no established pharmacological treatment currently available. By targeting TRPV4, our study suggests the importance of further exploration and development of therapeutics to address this pressing health issue.