Functional mechanism of tracheal relaxation,antiasthmatic, and toxicological studies of 6-hydroxyflavone |
| |
Authors: | Angélica Flores-Flores Samuel Estrada-Soto César Millán-Pacheco Blanca Bazán-Perkins Rafael Villalobos-Molina Leticia Moreno-Fierros Rogelio Hernández-Pando Sara García-Jiménez Julio César Rivera-Leyva |
| |
Affiliation: | 1. Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico;2. Instituto Nacional de Enfermedades Respiratorias, Ciudad de México, Mexico Escuela de Medicina y Ciencias de la Salud, Tecnológico de Monterrey, Ciudad de México, Mexico;3. Unidad de Biomedicina, FES-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, Mexico Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico;4. Unidad de Biomedicina, FES-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, Mexico;5. Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, Mexico |
| |
Abstract: | Previously, we described tracheal rat rings relaxation by several flavonoids, being 6-hydroxyflavone (6-HOF) the most active derivative of the series. Thus, its mechanism of action was determined in an ex vivo tracheal rat ring bioassay. The anti-asthmatic effect was assayed in in vivo OVAlbumin (OVA)-sensitized guinea pigs. Finally, the toxicological profile of 6-HOF was studied based on Organization of Economic Cooperation and Development guidelines with modifications. 6-HOF–induced relaxation appears to be related with receptor-operated calcium channel and voltage-operated calcium channel blockade as the main mechanism of action, and also through the production of relaxant second messengers NO and cGMP. Molecular docking supports that 6-HOF acts as calcium channel blocker and by activation of nitric oxide synthase. In addition, the in vivo anti-asthmatic experiments demonstrate the dose-dependent significant anti-allergic effect of 6-HOF induced by OVA, with best activity at 50 /kg. Finally, toxicological studies determined a LD50 > 2,000 mg/kg and, after 28 day of treatment with 6-HOF (50 mg/kg) by intragastric route, mice did not exhibit evidence of any significant toxicity. In conclusion, experiments showed that 6-HOF exerts significant relaxant activity through calcium channel blockade, and possibly, by NO/cGMP-system stimulation on rat trachea, which interferes with the contraction mechanism of smooth muscle cells in the airways. In addition, the flavonoid shows potential anti-asthmatic properties in an anti-allergic pathway. Furthermore, because the pharmacological and safety evidence, we propose this flavonoid as lead for the development of a novel therapeutic agent for the treatment of asthma and related respiratory diseases. |
| |
Keywords: | 6-hydroxyflavone allergy asthma calcium channel blockade toxicology tracheal relaxation |
|
|