A tetrahydrophthalazine derivative 'sodium nucleinate" exerts a potent suppressive effect upon LPS-stimulated mononuclear cells in vitro and in vivo.

We described the use of a new chemical substance Sodium nucleinate (SN) as an immunomodulatory substance exhibiting antiinflammatory properties. Sodium nucleinate (SN) registrated in Russian Federation as Tamerit, is 2-amino-1,2,3,4-tetrahydrophthalazine-1,4-dione sodium salt dihydrate, derivative of well known chemical substance luminol. To comprehend the mechanisms of SN immunomodulatory activity, we examined the SN modulation of the innate inflammatory cytokine response of human PBMC stimulated with LPS in vitro. Furthermore, we studied the immunomodulatory effects of SN in mice challenged with E. coli LPS in vivo to investigate a possible novel approach to therapy of excessive inflammation that interfere with the response to endotoxin and inflammatory mediators. Our results demonstrated that SN is an efficient inhibitor of sepsis development in mice model of LPS-induced sepsis. The changes induced by SN include decreased mice plasma inflammatory cytokine production. Simmilary we demonstrated a decreased TNF-alpha, IFN-gamma and IL-6 response in human LPS-stimulated PBMNCs. SN was therefore shown to be a promising inhibitor of multiple inflammatory cytokine secretion.