Abstract
Bergenin (
1), a C-glycoside of 4-
O-methyl gallic acid, isolated from rhizomes of
Bergenia stracheyi (Saxifragaceae) and its
O-demethylated derivative norbergenin (
2), prepared from
1, are reported to show anti-arthritic activity through possible modulation of Th1/Th2 cytokine balance. Flow cytometric study showed that the oral administration of
1 and
2 at doses of 5, 10, 20, 40 and 80
mg/kg per oral dose inhibit the production of proinflammatory Th1 cytokines (IL-2, IFN-γ and TNF-α) while as potentiate anti-inflammatory Th2 cytokines (IL-4 and IL-5) in the peripheral blood of adjuvant-induced arthritic balb/c mice. This shows the potential Th1/Th2 cytokine balancing activity of
1 and
2 which is strongly correlated with their anti-arthritic activity. At similar dose levels, the effect of
2 was found to be more than that of
1. The oral LD
0 for
1 and
2 was more than 2000
mg/kg body weight of the mice.