Expression of inducible nitric oxide synthase induced by lipid-associated membrane proteins of Ureaplasma urealyticum is regulated by nuclear factor κB-mediated mechanism in murine macrophages

摘要

The aim was to investigate the molecular mechanisms responsible for the inducible nitric oxide synthase (iNOS) gene expression stimulated by lipid associated membrane proteins (LAMPs) of Ureaplasma urealyticum (U.urealyticum). Detection of NO, the expression of iNOS and the activation of nuclear factor κB (NF-κB) in direct response to U.urealyticum LAMPs in a murine macrophages, the effects of pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB and of cycloheximide (CHX), a protein synthase inhibitor were available. The results indicated that U.urealyticum LAMPs stimulated mouse macrophages to express iNOS and thus produce NO in dose- and time-dependent manner by activating NF-κB. The expression of iNOS, NO production and the activation of NF-κB were inhibited by U.urealyticum LAMPs combination with PDTC or CHX. In conclusion, our findings suggest that U.urealyticum may be an etiological factor to certain diseases due to its ability to stimulate the expression of iNOS, which is probably mediated through the activation of NF-κB.