Effect of botulinum toxin type A on nasal mucociliary transport in rabbits

• Grant number: 11/07465-3
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2011
• End date: July 31, 2014
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Richard Louis Voegels
• Grantee: Richard Louis Voegels
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• City of the host institution: São Paulo
• Associated researchers: Mariangela Macchione ; Mary Anne Kowal Olm. ; Naomi Kondo Nakagawa ; Paulo Hilário Nascimento Saldiva ; Regiani Carvalho de Oliveira ; Waldir Carreirão Neto

Abstract

Rhinitis is defined as inflammation of the nasal mucosa, characterized by symptoms such as nasal congestion, rhinorrhea, itching, sneezing and hyposmia. Up to 47% of the brazilian population might experience symptoms of rhinitis annum. Botulinum toxin type A (BTX-A) has been tested in the treatment of rhinitis, improving symptoms as rhinorrhea. Mucociliary transport (MCT), the main primary defense mechanism of the nasal mucosa, to be effective, depends on an adequate production of mucus and a coordinated ciliary activity. Acetylcholine is an important neurotransmitter involved in this mechanism. The BTX-A acts by preventing the release, by the nerve cell, of vesicles containing acetylcholine. This can occur in all peripheral cholinergic sites, including the peripheral parasympathetic nervous system. Considering the action of acetylcholine in stimulating ciliary beat frequency (CBF), and the local cholinergic blocking action of BTX-A, few studies have reported the possible interference of BTX-A in the MCT. This study will evaluate the effect of BTX-A on MCT on the rabbits nasal mucosa, more specifically about the FBC by phase contrast microscopy and digital high speed imaging. There will also be analyzed the: 1) expression of interleukin (IL) -4, IL-5, IL-13, interferon-c, IL-2, nuclear factor-kB, IL-10, IL-1ra, CD4 + / CD3 + lymphocyte count , and signs of apoptosis by immunohistochemistry; 2) the rheological properties of mucus by the cone-plate viscosimeter, 3) transportability of mucus by coughing, and 4) the wettability of the mucus through contact angle. (AU)