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The pyrrolizidine alkaloids (PA) are toxic compounds which occur naturally in plant species throughout the world. They have been implicated as both carcinogenic and mutagenic agents. An active metabolite of the alkaloids, the pyrrole, which is a strong alkylating agent, is thought to be the
Pyrrolizidine alkaloid poisoning in humans is associated with the consumption of plants containing the alkaloids, either as contaminants of grains or as infusions for medicinal purposes. The alkaloids are carcinogenic in rats but have not been associated, so far, with tumors in humans. For the known
Large outbreaks of acute food-related poisoning, characterized by hepatic sinusoidal obstruction syndrome, hemorrhagic necrosis, and rapid liver failure, occur on a regular basis in some countries. They are caused by 1,2-dehydropyrrolizidine alkaloids contaminating locally grown grain. Similar acute
The carcinogenicity of the pyrrolizidine alkaloids senkirkine and symphytine was studied in male inbred ACI rats. Animals were divided into 3 groups: Group I received ip injections of freshly prepared senkirkine at a dose of 10% of the median lethal dose (LD50) twice weekly for 4 weeks and then once
Humans and animals can be exposed to carcinogenic pyrrolizidine alkaloids (PAs) through consumption of plants commonly found in many parts of the world. Although the liver is the primary target organ for carcinogenic PAs, they have also induced lung tumors in rodents. Hepatic cytochrome P450
Two new pyrrolizidine alkaloids, sclerwalins A and B (1 and 2), and one known 9-O-E-hydroxysenecioylretronecine (3) were first isolated from the seeds of Scleropyrum wallichianum. Their chemical structures were elucidated by extensive 1 D NMR and 2 D NMR (HSQC, HMBC,
The carcinogenic activity of clivorine, a pyrrolizidine alkaloid isolated from Ligularia dentata, was studied in inbred ACI rats. Twelve animals in the experimental group received a 0.005% solution of clivorine in drinking water for 340 days and survived beyond 440 days after the beginning of the
The carcinogenic activity of petasitenine, a new pyrrolizidine alkaloid isolated from young flower stalk of Petasites japonicus, was studied in ACI rats. All rats that had received a 0.05% solution of petasitenine in drinking water died or were killed in moribund condition 72 days after the start of
OBJECTIVE
One major cause of hepatic sinusoidal obstruction syndrome (HSOS) is the consumption of products containing pyrrolizidine alkaloids (PA). As the use of herbal preparations has increased in China, so has the number of reports of HSOS induced by ingesting PA-containing herbs. The aim of the
Lasiocarpine (LC), a pyrrolizidine alkaloid, is able to induce a series of chronic and progressive lesions in rat liver, including a long-lasting block in the cell cycle, the appearance of enlarged hepatocytes (megalocytosis), fibrosis, cirrhosis and malignant neoplasma. In this study the effect of
Pyrrolizidine alkaloids (PA) are secondary plant metabolites that occur as food and feed contaminants. Acute and subacute PA poisoning can lead to severe liver damage in humans and animals, comprising liver pain, hepatomegaly and the development of ascites due to occlusion of the hepatic sinusoids
The methanolic extract of the whole plant of Echium glomeratum Poir. (Boraginaceae) has afforded five pyrrolizidine alkaloids, three that were (7S, 8R)-petranine (1), (7S, 8S)-petranine (2), and (7R, 8R)-petranine (3a) or (7R, 8S)-petranine (3b), comprising a tricyclic pyrrolizidine alkaloids
The administration of anticancer drugs during chemotherapy treatments has increased considerably in recent years, and based on the growing incidence of cancer worldwide there is a foreseen increase in their use over the coming years. Many anticancer drugs are not removed by conventional wastewater
Repeated topical doses of dehydromonocrotaline, a putative primary toxic metabolite of the pyrrolizidine alkaloid monocrotaline, followed by repeated treatments with croton oil, produced malignant tumours of the skin in LACA mice. A chemically similar alkylating agent,