Biochemical and pharmacological characterization of toxins obtained from the fire coral Millepora complanata
Por:
Ibarra-Alvarado C., Alejandro García J., Aguilar M.B., Rojas A., Falcón A., Heimer de la Cotera E.P.
Publicada:
1 ene 2007
Resumen:
Millepora complanata is a normal resident of coral reefs in the Mexican Caribbean. In this study, we describe for the first time the vasoconstrictor, phospholipase A2 (PLA2), and hemolytic activities elicited by a crude extract obtained from M. complanata. This extract caused a concentration-dependent contraction of isolated rat aortic rings (EC50 = 22.4 ± 1.1 ?g protein/mL). This effect was endothelium independent and significantly reduced in the absence of extracellular Ca2+ and when the intracellular Ca2+ stores were depleted. In addition, the crude extract obtained from M. complanata showed PLA2 activity (7.231 ± 0.092 mmol min- 1 mg- 1) and hemolysis of rat erythrocytes (HU50 = 1.64 ± 1.04 ?g protein/mL). The hemolysis increased in the presence of Ca2+ and decreased in the presence of cholesterol. Furthermore, this hemolysis was significantly reduced after incubation with an inhibitor of PLA2 enzymes. The hemolytic and vasoconstrictor effects were abolished after incubating the extract under denaturing conditions. Reverse phase chromatography of the M. complanata extract afforded 19 fractions (F1 to F19). F4 induced hemolysis and contained mainly a protein of 30 kDa, probably a PLA2 enzyme, while F8 and F11, containing mainly proteins of 15 and 20 kDa respectively, produced vasoconstrictor effects mediated by different mechanisms of action. © 2007 Elsevier Inc. All rights reserved.
Filiaciones:
Ibarra-Alvarado C.:
Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, 76010 Qro, Mexico
Alejandro García J.:
Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, 76010 Qro, Mexico
Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Querétaro, 76230, Mexico
Aguilar M.B.:
Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Querétaro, 76230, Mexico
Rojas A.:
Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, 76010 Qro, Mexico
Falcón A.:
Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Querétaro, 76230, Mexico
Heimer de la Cotera E.P.:
Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Querétaro, 76230, Mexico
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