TRICHOMONAS VAGINALIS: IDENTIFICATION OF A PHOSPHOLIPASE A–DEPENDENT HEMOLYTIC ACTIVITY IN A VESICULAR SUBCELLULAR FRACTION

• Published in: The Journal of parasitology 2003-02, Vol.89 (1), p.105-112
• Main Authors: Vargas-Villarreal, Javier, Mata-Cárdenas, Benito D, González-Salazar, Francisco, Lozano-Garza, Héctor G, Cortes-Gutierrez, Elva I, Palacios-Corona, Rebeca, Martínez-Rodríguez, Herminia G, Ramírez-Bon, Enrique, Said-Fernández, Salvador
• Format: Article
• Language: English
• Subjects: Animals; Biochemistry; Biochemistry. Physiology. Immunology. Molecular biology; Biological and medical sciences; Calcium - metabolism; Dose-Response Relationship, Drug; Enzymes; Epithelial cells; Erythrocytes; Erythrocytes - metabolism; Fundamental and applied biological sciences. Psychology; Hemolysin proteins; Hemolysis; Hemolysis - physiology; Humans; Hydrogen-Ion Concentration; Invertebrates; Nemathelminthia. Plathelmintha; Parasitism; Parasitology; PATHOLOGY; Phospholipases A - antagonists & inhibitors; Phospholipases A - metabolism; Physiology. Development; Rats; Stearates - pharmacology; Subcellular fractions; Trichomonas vaginalis - enzymology; Trichomonas vaginalis - metabolism; Trichomonas vaginalis - pathogenicity; Virulence
• ISSN: 0022-3395; 1937-2345
• DOI: 10.1645/0022-3395(2003)089[0105:TVIOAP]2.0.CO;2

Trichomonad total extracts (TTE), or vesicular (P30) and soluble (S30) subcellular fractions from 3 pathogenic Trichomonas vaginalis strains (GT-3, GT-13, and GT-15), lysed both human and Sprague–Dawley rat erythrocytes in a time- and dose-dependent manner. The entire hemolytic activity of TTE was located in P30, showing 2 peaks of maximum activity, one at pH 6.0 and another at pH 8.0, in the presence of 1 mM Ca2+. Hemolytic activity on rat erythrocytes was greater at pH 6.0 (6.71 ± 0.33 hemolytic units [HU]/mg/hr to 11.60 ± 0.24 HU/mg/hr) than at pH 8.0 (3.81 ± 0.30 HU/mg/hr to 5.75 ± 0.65 HU/mg/hr), and it was greater than that on human red blood cells at pH 6.0 (2.67 ± 0.19 HU/mg/hr to 4.08 ± 0.15 HU/mg/hr) or pH 8.0 (2.24 ± 0.09 HU/mg/hr to 2.81 ± 0.06 HU/mg/hr). The alkaline and acidic hemolytic activity diminished (60–93% at pH 6.0 and 78–93% at pH 8.0) by the effect of 80 μM Rosenthal's inhibitor, which also inhibited 27–45% and 29–54% trichomonad alkaline and acidic phospholipase A activities, respectively. Vesicles, vacuoles, and hydrogenosomes were rich in P30. Trichomonas vaginalis has a hemolytic PLA, which could be involved in its cytopathogenic mechanism.