Prevention of Taurolithocholate-Induced Hepatic Bile Canalicular Distortions by HPLC-Characterized Extracts of Artichoke (Cynara scolymus) Leaves[*]

Abstract

The effects of water-soluble extracts of artichoke (Cynara scolymus L.) leaves on taurolithocholate-induced cholestatic bile canalicular membrane distortions were studied in primary cultured rat hepatocytes using electron microscopy. Artichoke extracts at concentrations between 0.08 and 0.5 mg/ml were able to prevent the formation of bizarre canalicular membrane transformations in a dose-dependent manner when added simultaneously with the bile acid. However, prevention also occurred when the hepatocytes were preincubated with the extracts, indicating that absorption of the bile acid to components of the extracts was not involved. These results demonstrate that artichoke leaf extracts exert a potent anticholestatic action at least in the case of taurolithocholate. This effect may contribute to the overall hepatoprotective influence of this herbal formulation.

Key words

Cynara scolymus - Asteraceae - artichoke leaf extracts - bile canaliculi - cholestasis - hepatocyte cultures - taurolithocholate

1 * Part of the experimental work was done at the Physiologisch-chemisches Institut, Hoppe-Seyler-Str. 4, while affiliated with the University of Tübingen, 72 076 Tübingen, Germany

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1 * Part of the experimental work was done at the Physiologisch-chemisches Institut, Hoppe-Seyler-Str. 4, while affiliated with the University of Tübingen, 72 076 Tübingen, Germany