Cytochrome P450 Induction
Cytochrome P450 Induction - Related Videos
01:28
Pharmacogenetics of Phase I Enzymes: Cytochrome P450 Isozymes
0 Views •
2026
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,...
07:42
Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c
0 Views •
Cited by 15 •
2011
In this protocol, we describe the direct cytoplasmic microinjection of cytochrome c protein into fibroblasts and primary sympathetic neurons. This technique allows for the introduction of cytochrome c protein into the cytoplasm of cells and mimics the release of cytochrome c from mitochondria, which occurs during apoptosis.
11:06
Encapsulating Cytochrome c in Silica Aerogel Nanoarchitectures without Metal Nanoparticles while Retaining Gas-phase Bioactivity
0 Views •
Cited by 1 •
2016
This procedure describes how to encapsulate cytochrome c (cyt. c) in silica (SiO2) sol-gels, process these gels to form bioaerogels, and use these bioaerogels to rapidly recognize nitric oxide (NO) through a gas-phase reaction. This type of protocol may aid in the future development of biosensors or other bioanalytical devices.
11:33
Inductance
0 Views •
2023
Source: Yong P. Chen, PhD, Department of Physics & Astronomy, College of Science, Purdue University, West Lafayette, IN This experiment will use inductive coils to demonstrate the concept of inductor and inductance. Magnetic induction will be demonstrated using a rod magnet inserted into or extracted away from the core of a coil to induce a transient electromotive force (emf) voltage in the coil, measured by a voltmeter. This experiment will also demonstrate the mutual inductance between...
14:01
Anesthesia Induction and Maintenance
0 Views •
2016
Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN The Guide for the Care and Use of Laboratory Animals ("The Guide") states that pain assessment and alleviation are integral components of the veterinary care of laboratory animals. The definition of anesthesia is the loss of feeling or sensation. It is a dynamic event involving changes in anesthetic depth with respect to an animal's metabolism, surgical stimulation, or variations in the...
FAQs
Pregnane X receptor and constitutive androstane receptor function as nuclear receptors that regulate transcription of CYP genes. When activated by an inducing chemical or drug, they can increase production of particular cytochrome P450 enzymes. This receptor-mediated control explains why induction changes enzyme abundance and can subsequently alter the metabolic handling of other substances.
Inducing compounds increase the expression or activity of specific cytochrome P450 enzymes, not necessarily the entire enzyme system. The affected enzyme determines which substances may be metabolized more rapidly. Consequently, the clinical effect depends on the relationship between the inducer, the particular CYP enzyme involved, and the drug or chemical processed by that enzyme.
For many medicines, accelerated metabolism lowers therapeutic drug concentrations and may reduce treatment effectiveness. The outcome can differ for a prodrug, because increased metabolism may enhance formation of its active metabolite. Evaluating induction therefore requires attention to whether the affected substance is an active drug or depends on metabolic conversion for activity.
Hepatic cytochrome P450 enzymes are central to the metabolism of many drugs and chemicals. When their expression or activity increases, hepatic processing can become faster, changing the amount of substance that remains available in the body. This hepatic mechanism provides a basis for anticipating altered drug concentrations, possible treatment failure, or toxicity.
Assessment focuses on whether exposure to a chemical or drug increases the expression or activity of specific cytochrome P450 enzymes and whether this changes substance metabolism. The resulting pharmacokinetic information helps connect enzyme induction with altered drug concentrations. In medicine, these findings support predictions about interactions, treatment response, and the need for dose adjustment.
Prescribers should consider it when a patient receives substances that may alter cytochrome P450 activity alongside other medicines. Increased metabolism can lower concentrations of a therapeutic drug or change active-metabolite formation for a prodrug. Recognizing these possibilities supports safer prescribing, helps anticipate treatment failure or toxicity, and informs decisions about dose adjustment.
It provides a mechanistic explanation for how one drug or chemical can change the handling of another. By identifying receptor-regulated increases in specific CYP enzymes, researchers can predict faster metabolism and altered therapeutic exposure. This information is used in pharmacokinetic evaluation and helps assess whether a combination could compromise efficacy or increase toxicity.