Kaempferitrin induces immunostimulatory effects in vitro.

BACKGROUND

Justicia spicigera is a plant used as immunostimulatory in Mexican traditional medicine. Recently, we showed that Justicia spicigera extracts exerted immunostimulatory effects and the major component of this extract was kaempferitrin (KM). This work shows a correlation between the medical traditional use of Justicia spicigera and kaempferitrin, its active compound.

METHODS

The in vitro immunostimulatory effects of KM were evaluated on the proliferation of murine splenocytes and macrophages, and human peripheral blood mononuclear cells (PBMC). The effects of KM on NO production, lysosomal enzyme activity and neutral red uptake were assayed in murine macrophages RAW 264.7. The effects of KM on the NK cell activity were also assayed.

RESULTS

KM at 25μM, the highest concentration tested, increased the proliferation of murine macrophages (23%) and splenocytes (17%), and human PBMC (24%) in the absence of lipopolysaccharides (LPS), compared to untreated cells. KM also stimulated the pinocytosis (25%) and lysosomal enzyme activity (57%) in murine macrophages with a similar potency than LPS 1μg/ml. In addition, KM induced the NK cell activity (11%).

CONCLUSIONS

KM exerts immunostimulatory effects on immune responses mediated by splenocytes, macrophages, PBMC and NK cells.