Inhibition of (S)-armepavine from Nelumbo nucifera on autoimmune disease of MRL/MpJ-lpr/lpr mice.

T cell immune responses play important roles in the pathogenesis of systemic lupus erythematosus (SLE). (S)-Armepavine (C19H23O3N; MW313) from Nelumbo nucifera suppresses T cells proliferation. To study its potential benefit on SLE, we examined effects of (S)-armepavine on MRL/MpJ-lpr/lpr mice, which have similar disease features to human SLE. MRL/MpJ-lpr/lpr mice were treated orally with (S)-armepavine for 6 weeks and their SLE characteristics were evaluated. The results revealed that (S)-armepavine prevented lymphadenopathy and elongated life span of MRL/MpJ-lpr/lpr mice. It seemed to be mediated by inhibition of splenocytes proliferation, suppression of interleukin-2 (IL-2), interleukin-4, interleukin-10, and interferon-γ (IFN-γ) gene expressions, reduction of glomerular hypercellularity and immune complexes deposition, and decrease of urinary protein and anti-double stranded DNA autoantibody production. Furthermore, the data demonstrated (S)-armepavine impaired IL-2 and IFN-γ transcripts in human peripheral blood mononuclear cells. We suggest that (S)-armepavine may be an immunomodulator for the management of autoimmune diseases like SLE.