Abstract: Objective To investigate the spectrum-effect relationship between the total anthraquinone extract of Cassia seeds and fluorouracil (5-Fu)-induced liver injury in mice and identify the effective components in the extract. Methods A mouse model of liver injury was established by intraperitoneal injection of 5-Fu, with bifendate as the positive control. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and myeloperoxidase (MPO), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in the liver tissue were detected to investigate the effect of the total anthraquinone extract of Cassia seeds (0.4, 0.8 and 1.6 g/kg) on liver injury induced by 5-Fu. HPLC fingerprints of 10 batches of the total anthraquinone extracts were established to analyze the spectrum- effectiveness of the extract against 5- Fu-induced liver injury in mice and screen the effective components using the grey correlation method. Results The 5- Fu- treated mice showed significant differences in liver function parameters from the normal control mice (P<0.05), suggesting successful modelling. Compared with those in the model group, serum ALT and AST activities were decreased, SOD and T-AOC activities significantly increased, and MPO level was significantly lowered in the mice treated with the total anthraquinone extract (all P<0.05). HPLC fingerprints of the 31 components in the total anthraquinone extract of Cassia seeds showed good correlations with the potency index of 5-Fu-induced liver injury but with varying correlation strengths. The top 15 components with known correlations included aurantio-obtusina (peak 6), rhein (peak 11), emodin (peak 22), chrysophanol (peak 29) and physcion (peak 30). Conclusion The effective components in the total anthraquinone extract of Cassia seeds, including aurantio-obtusina, rhein, emodin, chrysophanol, and physcion, are coordinated to produce protective effects against 5-Fu-induced liver injury in mice.

Key words: total anthraquinone extract from Cassia seeds; fluorouracil; liver injury; spectral effect relationships; effective components