Oridonin ameliorates lupus-like symptoms of MRL(lpr/lpr) mice by inhibition of B-cell activating factor (BAFF).

Oridonin, a pharmacologically safe agent extracted from Isodon Serra, has been shown to possess potent anti-inflammatory properties. However, it is not clear whether Oridonin affects B-cell activating factor (BAFF) expression, thereby exerting beneficial effects in the treatment of BAFF-associated autoimmune diseases such as systemic lupus erythematosus (SLE). Thus, the current study aimed to find the function of Oridonin in regulation of BAFF and amelioration of SLE. In vitro, we explored the effect of Oridonin on BAFF expression and production in mouse macrophages. Moreover, using a spontaneous murine SLE model, we investigated the role of Oridonin delivery in the treatment of lupus-like disease in MRL(lpr/lpr) mice, by measuring the changes in lupus symptoms, renal damage, BAFF expression, and B cell subsets. Our results showed that Oridonin significantly inhibited BAFF expression in mouse macrophages by suppressing the transcriptional activation of its promoter. And in vivo administration of Oridonin efficiently ameliorated the serological and clinical manifestations of SLE in MRL(lpr/lpr) mice, as shown by increased survival benefit, reduced proteinuria levels, diminished production of specific auto-antibodies, and attenuated renal damage, in association with down-regulation of BAFF and a lower rate of B-cell maturation and differentiation. Thus, it suggests that Oridonin will serve as a novel natural therapeutic strategy for SLE by inhibition of BAFF.