Role of nitric oxide on human schistosomiasis mansoni: upregulation of in vitro granuloma formation by N omega-nitro-L-arginine methyl ester.

Abstract

Over the past decade, nitric oxide has been intensely studied due to its relevance as a widespread intra- and intercellular messenger and as a cytotoxin released during several physiopathological events, including immunological reactions and inflammation. In the present paper, we investigate the effect of inhibition of NO synthesis, using an analogue of L-arginine, N omega-nitro-L-arginine methyl ester (L-NAME), on in vitro granulomatous formation of human peripheral blood mononuclear cells (PBMC) from Schistosoma mansoni-infected individuals. The results demonstrated that human PBMC are capable of in vitro NO production and that inhibition of its production through the addition of L-NAME is responsible for exacerbating granulomatous reaction. This L-NAME-induced granuloma enhancement (ranging from 30 to 65%) was measured using the granuloma index. Furthermore, we observed a general time-dependent increase in NO production during the period of cell culture (21 days) and an inverse relationship between nitrite detection and granuloma reactivity. Collectively, our results point to a possible regulatory role of NO on the development of granulomatous inflammation.

Cite this paper

@article{Oliveira1998RoleON, title={Role of nitric oxide on human schistosomiasis mansoni: upregulation of in vitro granuloma formation by N omega-nitro-L-arginine methyl ester.}, author={Daiani Moraes Oliveira and David Nascimento Silva-Teixeira and Sara Carmo and Alfredo de Miranda G{\'o}es}, journal={Nitric oxide : biology and chemistry}, year={1998}, volume={2 1}, pages={57-65} }