综述
Cai Haodong;Sun Fengxia
2007, 9(4): 229-234.
Pyrrolizidine alkaloids (Pas) in the plants is one of the main causes of hepatic veno-occlusive disease occurring.Cases of hepatic veno-occlusive disease or liver damage associated with Pas-containing plants or medicinal herbs have been reported in America, England, China, and many other countries. There are more than six thousands kinds of the plants that contain Pas in the whole world. The Pas are primarily found in members of four plant families, I.e. (1) Compositae family: mainly in the genera Senecio, Ligularia, Eupatorium, Gynura, and Petasites; (2) Boraginaceae family: all plants of this family; (3) Leguminosae family: mainly in the genus Crotalaria; (4) Orchidaceae family: in the genus Liparis. There are thirty-eight kinds of Pas-containing medicinal herbs in China, and twelve of them are common in clinical practice as follows: Senecio scanden, Senecio campestri, Gynura segetum, Tussilago farfara, Herba Eupatorii, Herba lycopi, Radix Asters, Lithospermum, Heliotropium, Crotalaria sessiliflora, Crotalaria pallide, Liparis. The Pas have minimal toxicity in their original form, but their metabolites have hepatoxicity. In most instances of Pas liver toxicity in adults, the daily intake was several milligrams or hundreds of milligrams. However, it has been suggested by the WHO that the lowest intake of Pas that cause veno-occlusive disease in a human is just 0.015 mg/(kg·d). For a 70 kg adult, that would correspond to 1 mg total per day. The clinical manifestations of hepatic veno-occlusive disease are mainly refractory ascites, jaundice, hepatomegalia. There are no specific therapy for hepatic veno-occlusive disease, except symptomatic therapy and supportive therapy. Recently, the glucocorticosteroid or heparin therapy for Pas intoxication is reported, but their effect and safety are still under research. The authors consider that the education and monitoring for Pas-containing plants intoxication should be strengthened in our country.
