Pharmaceutical Research

, Volume 8, Issue 2, pp 273–277 | Cite as

Protection Against Microcystin-LR-Induced Hepatotoxicity by Silymarin: Biochemistry, Histopathology, and Lethality

  • Kay A. Mereish
  • David L. Bunner
  • Danny R. Ragland
  • Donald A. Creasia


Microcystin-LR, a cyclic heptapeptide synthesized by the blue-green algae, Microcystis aeruginosa, is a potent hepatotoxin. Pathological examination of livers from mice and rats that received microcystin-LR revealed severe, peracute, diffuse, centrilobular hepatocellular necrosis, and hemorrhage. These changes were correlated with increased serum activities of sorbitol dehydrogenase, alanine aminotransferase, and lactate dehydrogenase. Pretreatment of either rats or mice with a single dose of silymarin, a flavonolignane isolated from the wild artichoke (Silybum marianum L. Gaertn), completely abolished the lethal effects, pathological changes, and significantly decreased the levels of serum enzymes induced by microcystin-LR intoxication.

alanine aminotransferase flavonoid hepatic necrosis hepatotoxin lactate dehydrogenase microcystin-LR silymarin sorbitol dehydrogenase 


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Copyright information

© Plenum Publishing Corporation 1991

Authors and Affiliations

  • Kay A. Mereish
    • 1
  • David L. Bunner
    • 1
  • Danny R. Ragland
    • 2
  • Donald A. Creasia
    • 3
  1. 1.Medical DivisionU.S. Army Medical Research Institute of Infectious DiseasesFrederick
  2. 2.Pathology DivisionU.S. Army Medical Research Institute of Infectious DiseasesFrederick
  3. 3.Pathophysiology DivisionU.S. Army Medical Research Institute of Infectious DiseasesFrederick

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