Related Experiment Video

Updated: Jun 25, 2026

Induction of Drug-Induced, Autoimmune Hepatitis in BALB/c Mice for the Study of Its Pathogenic Mechanisms
11:36

Induction of Drug-Induced, Autoimmune Hepatitis in BALB/c Mice for the Study of Its Pathogenic Mechanisms

Published on: May 29, 2020

Time-dependent induction of hepatic cytochrome P450 enzyme activity and mRNA expression by bilobalide in rats

Yuko Taki1, Yuko Yamazaki, Fumio Shimura

  • 1National Institute of Health and Nutrition, Japan.

Journal of Pharmacological Sciences
|March 12, 2009
PubMed

Insights

Bilobalide from Ginkgo biloba extract induces liver enzymes like cytochrome P450 (CYP) in rats. However, rapid elimination of bilobalide from the liver may limit this induction effect.

Area of Science:

  • Pharmacology
  • Hepatology
  • Drug Metabolism

Background:

  • Ginkgo biloba extract is widely used for cognitive enhancement.
  • Bilobalide is a key active component of Ginkgo biloba.
  • Cytochrome P450 (CYP) enzymes play a crucial role in drug metabolism and detoxification.

Purpose of the Study:

  • To investigate the effect of bilobalide on hepatic cytochrome P450 (CYP) enzyme activity and expression in rats.
  • To determine the time course of CYP induction by bilobalide.
  • To correlate bilobalide concentration with CYP induction.

Main Methods:

  • Administration of bilobalide (30 mg/kg) or Ginkgo biloba extract to rats via gavage.
  • Measurement of hepatic CYP enzyme activity and protein expression.
  • Quantitative RT-PCR to assess CYP2B mRNA levels.
  • Analysis of plasma and liver bilobalide concentrations.

Main Results:

  • A single dose of bilobalide induced hepatic CYP enzyme activity and protein expression in a time-dependent manner.
  • CYP2B mRNA expression peaked at 6 hours post-administration.
  • Bilobalide concentrations in plasma and liver correlated with mRNA expression patterns.
  • Rapid elimination of bilobalide from the liver was observed.

Conclusions:

  • Bilobalide significantly induces hepatic CYPs in rats.
  • The induction effect of bilobalide on hepatic CYPs may be limited by its rapid hepatic elimination.
  • These findings are relevant for understanding potential drug-herb interactions involving Ginkgo biloba.

More Related Videos

An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment08:59

An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment

Published on: December 3, 2020

Bile Duct Ligation in Mice: Induction of Inflammatory Liver Injury and Fibrosis by Obstructive Cholestasis08:56

Bile Duct Ligation in Mice: Induction of Inflammatory Liver Injury and Fibrosis by Obstructive Cholestasis

Published on: February 10, 2015

Related Concept Videos

Phase I Reactions: Oxidation of Aliphatic and Aromatic Carbon-Containing Systems01:19

Phase I Reactions: Oxidation of Aliphatic and Aromatic Carbon-Containing Systems

Phase I biotransformation reactions are integral to drug metabolism, predominantly involving oxidative, reductive, and hydrolytic transformations. Chief among these are oxidative reactions, which enhance the hydrophilicity of xenobiotics and introduce polar functional groups to facilitate their elimination from the body.
Oxidation reactions are fundamental in aromatic carbon-containing systems. An example is the hydroxylation of phenobarbital, a process that transforms it into...
Effect of Hepatic Disease on Pharmacokinetics: Drug Dosing and Hepatic Blood Flow01:26

Effect of Hepatic Disease on Pharmacokinetics: Drug Dosing and Hepatic Blood Flow

Chronic liver disease significantly impacts drug metabolism due to alterations in hepatic blood flow and enzyme accessibility. This disruption affects the body's pharmacokinetics—the movement and processing of drugs within the system. Key enzymes crucial for metabolizing medications become less accessible, changing how drugs are processed and utilized. Furthermore, liver disease influences the synthesis of plasma proteins, such as albumin and globulins, which play critical roles in drug binding...
Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test01:22

Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test

In clinical practice, the direct measurement of hepatic blood flow to evaluate liver function presents significant challenges due to the intricate and specialized nature of the necessary techniques. Consequently, healthcare professionals often rely on empirical estimates derived from thorough patient examinations and liver function tests to gauge liver health. Among the tools at their disposal, the Child–Pugh and MELD scoring systems stand out for their ability to categorize and assess the...
Drug Metabolism: Phase I Reactions01:17

Drug Metabolism: Phase I Reactions

A phase I reaction is a biochemical process that introduces a functionally reactive polar group to a substance. This transformation predominantly occurs in the liver, facilitated by the cytochrome P450 system of hemoproteins situated in the lipophilic endoplasmic reticulum of cells. The metabolite generated through this process can have varying polarities. If it is sufficiently polar, it can be easily excreted in the urine due to its water compatibility. However, if the metabolite is nonpolar,...
Pharmacogenetics of Phase I Enzymes: Cytochrome P450 Isozymes01:28

Pharmacogenetics of Phase I Enzymes: Cytochrome P450 Isozymes

Cytochrome P450 (CYP450) enzymes are a superfamily of heme-containing monooxygenases that play a pivotal role in Phase I drug metabolism by catalyzing oxidation and reduction reactions.These enzymes transform lipophilic xenobiotics into more hydrophilic metabolites, facilitating subsequent Phase II conjugation and eventual excretion. The CYP450 family is classified into families (e.g., CYP1–CYP3) and subfamilies (e.g., CYP2A, CYP2C), based on amino acid sequence homology.CYP450 isoenzymes,...
Jaundice01:25

Jaundice

Jaundice, or icterus, is the yellow discoloration of the skin, sclerae, and mucous membranes. It happens when plasma bilirubin levels rise above 2.5-3 mg/dL, leading to bilirubin deposition in tissue.Bilirubin is a byproduct of hemoglobin degradation. In macrophages, hemoglobin breaks down into globin and heme. Globin is converted into amino acids, while heme is turned into biliverdin by heme oxygenase, which is then reduced to unconjugated bilirubin by biliverdin reductase.Unconjugated...