Inhibitory effects of autoimmune disease by green tea in MRL-Faslprcg/Faslprcg mice.

To investigate whether green tea has inhibitory effects on the development of autoimmune disease (AID), one-month-old MRL-Faslprcg/Faslprcg mice were fed diets containing 2% green tea powder (GTP) for 3 months. At the end of GTP feeding, the weights of body, subcutaneous (s.c.) and intraperitoneal (i.p.) lymph nodes (LN), kidneys, spleen and intraperitoneal adipose tissue (IPAT), serological abnormalities and renal lesions were compared between GTP-fed and control mice. SCLN, IPLN, kidneys and IPAT weights in both sexes, spleen weight in males and body weight increase in males were significantly lower in GTP-fed mice. Particularly, LN hyperplasia and fatty accumulation were markedly reduced by GTP. Serum levels of anti-DNA antibodies and immune complexes (IC) were significantly lowered and proteinuria and blood urea nitrogen tended to be improved by GTP. The incidence of serious glomerulonephritis was significantly lower and nephric vasculitis was almost completely prevented in GTP-fed mice. Moreover, the survival of mice was significantly prolonged by GTP feeding for 6 months. These results indicate that the progression of lupus-like syndrome including glomerulonephritis was significantly delayed by reduced production of autoantibodies and IC in GTP-fed MRL-Faslprcg/Faslprcg mice, which led to the prolonged survival.