Effect of Green Tea and (+)-catechin on aristolochic acid-induced nephropathy in inbred mice

Many cases about aristolochic acid nephropathy (AAN) have been identified in recent years. The reason is that people mistaken the herb that contains aristolochic acid (AA). AAN is a unique type of nephropathy, which was characterized by extensive cell infiltration, tubular atrophy, and interstitial fibrosis. We established a chronic interstitial fibrosis model of AAN in inbred mice and investigated the efficacy of green tea (GT), (+)-catechin (CAT) on AAN. AA will be dissolved in distilled water (3μg/ml) and as drinking water ad libitum to C3H/He mice (6 weeks, male) for 56 days, the control group will be administered to distilled water. In the second experiment, they will be administered orally with GT (75, 150, 300 mg/kg), CAT (25, 50, 100 mg/kg) once daily for 14 days. The control group will be administered to distilled water. Urinary protein (UP), urinary N-acetyl-beta-D-glucosaminidase (NAG), blood urea nitrogen (BUN), blood glucose will determine. Renal tissues will serve to histological examination (PAS stain and immunofluorescence staining). The antibodies, including murine F4/80 macrophage, TGF-β (transforming growth factor-β), MMP-9 (matrix metalloproteinase-9), TNF-α (tumor necrosis factor-α) will be chosen to recognize the specific antigens, which deposited in injury sites. All animals will be treated with AA developed increased in UP, NAG, BUN, and blood glucose. In the histological examination, we will observe tubular atrophy, interstitial infiltration and fibrosis in the typical AAN. In the immunofluorescence stain assay, macrophage, TGF-β, MMP-9, and TNF-α will localize in the renal tissue.