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Protection by Osbeckia aspera against carbon tetrachloride-mediated alterations in microsomal drug metabolizing

K A Jayatilaka1, M I Thabrew

  • 1Department of Biochemistry, Faculty of Medicine, University of Ruhuna, Sri Lanka.

The Journal of Pharmacy and Pharmacology
|May 17, 2000
PubMed

Insights

Osbeckia aspera leaf extract protects against liver damage by reducing alterations in drug-metabolizing enzymes and inhibiting lipid peroxidation. The extract

Area of Science:

  • Pharmacology
  • Hepatoprotective Agents
  • Natural Product Chemistry

Background:

  • Carbon tetrachloride (CCl4) induces liver injury, primarily affecting endoplasmic reticulum and drug-metabolizing enzymes.
  • Aniline hydroxylase and p-aminopyrine N-demethylase are key microsomal enzymes sensitive to CCl4 toxicity.
  • Lipid peroxidation is a significant marker of CCl4-induced cellular damage.

Purpose of the Study:

  • To investigate the protective effects of Osbeckia aspera leaf extract against CCl4-induced liver injury.
  • To determine the impact of the extract on specific drug-metabolizing enzymes (aniline hydroxylase, p-aminopyrine N-demethylase).
  • To evaluate the extract's influence on phenobarbital-induced responses and lipid peroxidation.

Main Methods:

  • Administration of aqueous Osbeckia aspera leaf extract to rats before or after CCl4 exposure.
  • Measurement of aniline hydroxylase and p-aminopyrine N-demethylase activities.
  • Assessment of phenobarbital-induced righting reflex duration and malondialdehyde (MDA) levels for lipid peroxidation.

Main Results:

  • Osbeckia aspera extract significantly reduced CCl4-induced alterations in enzyme activities.
  • The extract mitigated CCl4-mediated lipid peroxidation, indicated by lower MDA formation.
  • Phenobarbital-induced sleeping time was normalized, and enzyme kinetics (Km values) remained unchanged, suggesting no induction or alteration of enzyme affinity.

Conclusions:

  • Osbeckia aspera leaf extract demonstrates significant hepatoprotective effects against CCl4-induced liver damage.
  • The extract protects liver cells by preserving drug-metabolizing enzyme function and inhibiting oxidative stress.
  • The protective mechanism does not involve enzyme induction or altered substrate affinity, highlighting a unique mode of action.

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