The anti-Trichomonas vaginalis phloroglucinol derivative isoaustrobrasilol B modulates extracellular nucleotide hydrolysis

5 years ago

The anti-Trichomonas vaginalis phloroglucinol derivative isoaustrobrasilol B modulates extracellular nucleotide hydrolysis

Danielle da Silva Trentin, Henrique Bridi, Gilsane Lino Poser, Alexandre José Macedo, Graziela Vargas Rigo, Tiana Tasca, Camila Braz Menezes

Trichomonas vaginalis causes trichomoniasis, a neglected sexually transmitted disease. Due to severe health consequences and treatment failure, new therapeutic alternatives are crucial. Phloroglucinols from southern Brazilian Hypericum species demonstrated anti-T. vaginalis and anti-Leishmania amazonensis activities. The modulation of biochemical pathways involved in the control of inflammatory response by ectonucleotidases, NTPDase, and ecto-5′-nucleotidase represents new targets for combating protozoa. This study investigated the activity of phloroglucinol derivatives of Hypericum species from southern Brazil against T. vaginalis as well as its ability on modulating parasite ectonucleotidases and, consequently, immune parameters through ATP and adenosine effects. Phloroglucinol derivatives screening revealed activity for isoaustrobrasilol B (IC50 38 μm) with no hemolytic activity. Although the most active compound induced cytotoxicity against a mammalian cell lineage, the in vivo model evidenced absence of toxicity. Isoaustrobrasilol B significantly inhibited NTPDase and ecto-5′-nucleotidase activities, and the immune modulation attributed to extracellular nucleotide accumulation was evaluated. The production of ROS and IL-6 by T. vaginalis-stimulated neutrophils was not affected by the treatment. Conversely, IL-8 levels were significantly enhanced. The associative mechanism of trophozoites death and ectonucleotidases modulation by isoaustrobrasilol B may increase the susceptibility of T. vaginalis to host innate immune cell like neutrophils consequently, contributing to parasite clearance. The phloroglucinol derivative of Hypericum species, isoaustrobrasilol B, was active against T. vaginalis. It significantly inhibited NTPDase and ecto-5′-nucleotidase activities, and the influence of extracellular nucleotide accumulation on immune mechanisms was evaluated revealing enhanced IL-8 levels in T. vaginalis-stimulated neutrophils. The associative effect of trophozoites death and ectonucleotidases modulation by isoaustrobrasilol B may increase the susceptibility of T. vaginalis to neutrophils consequently, contributing to parasite clearance.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1111/cbdd.13002