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Updated: May 23, 2026
A Simple and Efficient Method to Isolate Macrophages from Mixed Primary Cultures of Adult Liver Cells
Published on: May 24, 2011
Macrophage depletion ameliorates kavalactone damage in the isolated perfused rat liver
Abstract:
Liver toxicity is a side effect observed with some herbal treatments, including Piper methysticum. The possible mechanisms responsible include inflammation subsequent to activation of liver macrophages and oxidative damage. Hepatotoxicity of the pharmacologically active component of Piper methysticum (kavalactones) was tested in isolated, perfused livers from rats which were pretreated with the macrophage intoxicant gadolinium chloride. Perfusions without kavalactones in gadolinium chloride pretreated and untreated livers were included as negative controls. Serial liver lobe biopsies were collected to measure temporal changes in available (reduced) hepatic glutathione. There were no statistically significant changes in reduced glutathione over the course of perfusion in any experimental group. Liver damage was observed using electron microscopy. Hepatic sinusoids displayed extensive damage to the endothelium in kavalactone-perfused, rat livers. This damage was significantly reduced by pre-treatment with gadolinium chloride. Hence liver macrophages may be a factor in liver injury induced by Piper methysticum. Characterisation and modulation of the liver macrophage response may enable the development of strategies to avoid these hepatic side effects.
Insights
Piper methysticum (kava) can cause liver toxicity. Research suggests liver macrophages contribute to this kava-induced liver injury, highlighting potential therapeutic targets.
Area of Science:
- Pharmacology
- Hepatology
- Immunology
Background:
- Herbal remedies like Piper methysticum (kava) are associated with liver toxicity.
- Potential mechanisms involve inflammation from activated liver macrophages and oxidative stress.
Discussion:
- Kavalactones, active components of kava, induced significant damage to liver sinusoidal endothelium in isolated perfused rat livers.
- Pre-treatment with gadolinium chloride, a macrophage inhibitor, substantially reduced this endothelial damage.
- No significant changes in hepatic glutathione levels were observed, suggesting oxidative damage is not the primary mechanism in this model.
Key Insights:
- Liver macrophages play a role in Piper methysticum-induced liver injury.
- Endothelial damage is a key feature of kava hepatotoxicity.
- Gadolinium chloride mitigates kava-induced liver damage in this experimental system.
Outlook:
- Further characterization of liver macrophage activation by kava components is warranted.
- Modulating liver macrophage responses could lead to strategies for preventing kava hepatotoxicity.
- This research provides insights into the mechanisms of herbal medicine-induced liver injury.
