Anti-inflammatory effect of saikosaponins

The active principles extracted from the root of Bupleurum Chinese DC were injected to rats ip 150 or 300 mg/kg. A marked reduction in carrageenin-induced edema of the hind paw was noted. Saikosaponins showed a suppressing effect o histamine release, but the release of 5-HT and prostaglandins were not altered. Saikosaponins inhibited 5-HT histamine-induced swelling of the ankle, leaving those caused by PGE1 unaltered. Saikosaponins antagonized markedly the increase of capillary permeability due to 5-HT and histamine, while the action of PGE1 was left unchanged. Saikosaponins inhibited the leucocyte migratory response and the growth of rat granuloma caused by cotton pellets, accompanied by an adrenal hypertrophy an dthymic hypotrophy. Hence the antiphlogistic effects of saikosaponins are rather complicated. Apart from their stimulating property on the adrenal cortex, saikosaponins act on many inflammatory processes (exudation, capillary permeability, inflammatory mediator release, leucocyte migration and hyperplasia of connective tissues). The ip LD50 of saikosaponins in mice was 1.53+/-0.14 g/kg. It appears that saikosaponins may serve as a new anti-inflammatory agent for arthritis.