Related Experiment Video
Updated: Jun 28, 2026
04:51
Developing a Feeding Assay System for Evaluating the Insecticidal Effect of Phytochemicals on Helicoverpa armigera
Published on: May 26, 2023
Intra-herb pharmacokinetics interaction between quercetin and isorhamentin
Ke Lan1, Jian-lin He, Yang Tian
1Key Laboratory of Drug Targeting and Novel Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
Acta Pharmacologica Sinica
|October 29, 2008
Summary
Quercetin and isorhamnetin, found in herbal remedies, significantly interact within the body. This intra-herb interaction, involving P-glycoprotein (P-gp), impacts their pharmacokinetics, highlighting the importance of considering these effects in herbal medicine.
Area of Science:
- Pharmacology
- Pharmacokinetics
- Herbal Medicine
Background:
- Quercetin and isorhamnetin are common constituents in various herbal extracts.
- Understanding their interactions is crucial for optimizing herbal remedy efficacy.
Purpose of the Study:
- To investigate the intra-herb pharmacokinetic interactions between isorhamnetin and quercetin.
- To elucidate the role of P-glycoprotein (P-gp) in these interactions.
Main Methods:
- In vitro studies using MDR1-transfected MDCKII and Caco-2 cell assays to assess P-gp involvement.
- In vivo pharmacokinetic study in rats using a 3-way crossover design.
- Quantification of quercetin and isorhamnetin plasma concentrations via LC-MS/MS.
Main Results:
- Isorhamnetin efflux is mediated by P-gp, as shown by reduced permeability in MDR1-MDCKII cells.
- Co-transport of isorhamnetin and quercetin across Caco-2 cells significantly increased their permeability ratios.
- Coadministration in rats led to significantly higher Cmax and AUC values for both compounds compared to single administration.
Conclusions:
- A significant intra-herb pharmacokinetic interaction exists between quercetin and isorhamnetin.
- P-glycoprotein (P-gp) plays a key role, with potential involvement of other efflux pumps.
- Intra-herb interactions should be considered alongside drug-herb interactions in the use of herbal remedies.
Related Concept Videos
01:26Pharmacokinetics: Drug–Food and Drug–Viral Interactions
A drug interaction occurs when the concurrent use of another drug, food, or an external substance alters the pharmacological activity of a drug. This interaction can modify the action of the original drug, affecting its effectiveness and safety.Drug–food interactions are significant as they impact drug absorption, metabolism, and excretion. For example, grapefruit juice is a well-known disruptor of drug metabolism. It inhibits the cytochrome P450 3A4 enzyme, crucial for the metabolism of many...
01:25Pharmacokinetics: Drug–Drug Interactions
Drug interactions occur when the pharmacological effect of one drug is altered by another substance, either enhancing or diminishing its activity. The drug whose activity is altered is known as the object drug, and the substance causing the alteration is called the agent drug or the precipitant. The net effects of these interactions are mostly undesirable, leading to decreased effectiveness or increased adverse effects. In rare cases, interactions can be beneficial, such as the enhanced...
01:30Drug toxicity: Drug–Drug Interaction
Drug–drug interactions can precipitate toxicity through multiple mechanisms. Absorption interactions alter how drugs enter the body, exemplified when ranitidine increases the absorption of basic drugs, while cholestyramine decreases the levels of propranolol. Protein binding interactions occur when drugs share the same binding sites on plasma proteins. Drugs like aspirin and warfarin, when bound in excess, can lead to increased free drug concentrations, enhancing the potential for...
01:28Pharmacogenetics 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,...
01:08Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment
Hepatic impairment, characterized by decreased liver function, does not uniformly mandate adjustments in drug dosage. Whether dosage modifications are necessary depends on various factors related to the drug's metabolism and elimination pathways. If a drug is primarily excreted via the kidneys and bypasses significant hepatic processing, if it undergoes minimal metabolic transformation in the liver, or if it is volatile and primarily expelled through the lungs, dose adjustments may not be...
01:18Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Metabolism
Geriatric patients show significant variation in how their bodies process medications, which can change how effective and safe treatments are. The liver is the primary organ where drug metabolism occurs, involving two main types of chemical reactions: phase I and II. Phase I metabolism is driven by the cytochrome P450 enzyme system, which includes key types such as CYP3A, CYP2D6, and CYP2C9. Research indicates that while aging doesn't notably alter the levels or activity of these enzymes, it...