Seven Japanese Herbals Prolonged Cardiac Allograft Survival

Japanese herbal medicines have long been used as alternative therapy because of their immunomodulatory effects. In recent years, use herbal medicines is rapidly increasing worldwide. In this study, we investigated the effect of 17 components of traditional Japanese herbal medicines on alloimmune responses in a murine model of cardiac allograft transplantation. Fully vascularized heterotopic hearts from C57BL/6 donors were transplanted into CBA mice by using microsurgical techniques. Artemisiae capillaris herba (Inchinko) was given to CBA recipients at a dosage of 1 g/kg/day from the day of transplantation until 7 days afterward. The other 16 components were given at a dosage of 2 g/kg/day for the same time period. Naïve CBA mice rejected C57BL/6 cardiac grafts acutely (median survival time MST] of 7 days). CBA transplant recipients given 2 g/kg/day of Glycyrrhizae radix (Kanzou), Poria sclerotium (Bukuryo), Pinellia tuber (Hange), Cnidii rhizome (Senkyu), Paeoniae radix (Shakuyaku), and Scutellariae radix (Ogon) had prolonged C57BL/6 allograft survival significantly (MSTs were 18, 18, 17, 14, 12, and 12 days, respectively). Moreover, CBA transplant recipients given 1g/kg/day of Artemisiae capillaris herba had prolonged C57BL/6 allograft survival (MST >100 days); however, none of other 10 components prolonged allograft survival. In conclusion, administration of 7 components of traditional Japanese herbal medicines might induce prolongation of fully major histocompatibility complex–mismatched cardiac allografts.