piperine and Deglutition-Disorders

Oropharyngeal dysphagia (OD) is a major gastrointestinal motility disorder that causes severe nutritional and respiratory complications in elderly and neurological patients. In an earlier study, we found that stimulation of pharyngeal sensory neurons by capsaicinoids acting on transient receptor potential vanilloid 1 (TRPV1) improved the swallow response of dysphagic patients. The aim of this study was to explore the effect of piperine, a dual TRPV1/TRPA1 agonist, on the swallow response of dysphagic patients.. A videofluoroscopic study was performed to assess the signs of impaired safety and efficacy of swallow and the swallow response of 40 dysphagic patients while swallowing one series of nectar control boluses and two series of nectar boluses supplemented with piperine. Patients were randomized into two groups: one group received 150 μM piperine and the other group received 1 mM.. Piperine improved the safety of swallow by: (a) reducing the prevalence of unsafe swallows by -34.48% (P = 0.004) at 150 μM and -57.19% (P < 0.001) at 1 mM, and the severity score of the penetration-aspiration scale from 3.25 ± 0.51 to 1.85 ± 0.27 (P = 0.003, 1 mM); and (b) shortening the time to laryngeal vestibule closure from 0.366 ± 0.024 to 0.270 ± 0.022 s with 150 μM piperine (P < 0.001) and from 0.380 ± 0.032 to 0.306 ± 0.028 s with 1 mM piperine (P < 0.05).. Supplementing the alimentary bolus with piperine speeds swallow response and strongly improves safety of swallow in patients with OD, with a maximal therapeutic effect at 1 mM. Our results suggest that activation of TRPV1/A1 in oropharyngeal sensory neurons is a very promising neurostimulation strategy for dysphagic patients.

Topics: Administration, Oral; Aged; Alkaloids; Benzodioxoles; Calcium Channels; Deglutition; Deglutition Disorders; Dose-Response Relationship, Drug; Double-Blind Method; Female; Fluoroscopy; Humans; Male; Nerve Tissue Proteins; Piperidines; Polyunsaturated Alkamides; Sensory Receptor Cells; Transient Receptor Potential Channels; TRPA1 Cation Channel; TRPV Cation Channels; Video Recording

Fluid thickening is the main compensatory strategy for patients with oropharyngeal dysphagia (OD) associated with aging or neurological diseases, and there is still no pharmacological treatment. We aimed to compare the effects of increasing bolus viscosity with that of acute stimulation with TRPV1, TRPA1 or TRPM8 agonists on the biomechanics and neurophysiology of swallow response in patients with OD. We retrospectively analyzed seven studies from our laboratory on 329 patients with OD. The effect of increasing shear viscosity up to 3682 mPa·s was compared by videofluoroscopy and pharyngeal sensory evoked potentials (pSEP) with that of adding to the bolus: capsaicin (TRPV1, 150 μM/10 μM), piperine (TRPA1/V1, 1 mM/150 μM), menthol (TRPM8, 1 mM/10 mM), cinnamaldehyde-zinc (TRPA1, 100 ppm−70 mM), citral (TRPA1, 250 ppm) or citral-isopulegol (TRPA1-TRPM8, 250 ppm−200 ppm). Fluid thickening improved the safety of swallow by 80% (p < 0.0001) by delaying bolus velocity by 20.7 ± 7.0% and time to laryngeal vestibule closure (LVC) by 23.1 ± 3.7%. Capsaicin 150μM or piperine 1 mM significantly improved safety of swallow by 50% (p < 0.01) and 57.1% (p < 0.01) by speeding time to LVC by 27.6% (p < 0.001) and 19.5% (p < 0.01) and bolus velocity by 24.8% (p < 0.01) and 16.9% (p < 0.05), respectively. Cinnamaldehyde-zinc shortened the P2 latency of pSEPs by 11.0% (p < 0.01) and reduced N2-P2 amplitude by 35% (p < 0.01). In conclusion, TRPV1 and TRPV1/A1 agonists are optimal candidates to develop new pharmacological strategies to promote the recovery of brain and swallow function in patients with chronic OD.

Topics: Acrolein; Acyclic Monoterpenes; Alkaloids; Benzodioxoles; Biomechanical Phenomena; Capsaicin; Deglutition; Deglutition Disorders; Humans; Menthol; Piperidines; Polyunsaturated Alkamides; Retrospective Studies; Zinc