Ruscogenin glycoside (Lm-3) isolated from Liriope muscari improves liver injury by dysfunctioning liver-infiltrating lymphocytes

The effects of ruscogenin 1-O-[β-D-glucopyranosyl(1 → 2)] [β-D-xylopyranosyl(1 → 3)]-β-D-fucopyranoside (Lm-3) and its aglycone, ruscogenin, on liver injury induced in mice by delayed-type hypersensitivity to picryl chloride have been investigated. Lm-3 and ruscogenin significantly decreased liver injury when given during the effector phase of the delayed-type hypersensitivity reaction. The pretreatment of nonparenchymal cells, but not hepatocytes, with Lm-3 or ruscogenin in-vitro caused a concentration- and time-dependent inhibition against the damage. Lm-3 showed a stronger inhibition against the damage than ruscogenin (IC50: Lm-3 6.3 × 10^-10 M, ruscogenin 3.9 × 10^-7 M). However, neither Lm-3 nor ruscogenin blocked the hepatotoxic potential of CCl₄, when used to pretreat hepatocytes. Moreover, Lm-3 and ruscogenin inhibited concanavalin A-induced lymphocyte proliferation only at high concentrations. These results suggested that Lm-3 and ruscogenin improved the immunological liver injury by selectively causing dysfunction of the liver-infiltrating cells rather than by protecting hepatocyte membranes. Such characteristics would be significant for treating immunologically related liver diseases as well as for developing new drugs.