HOW IS xenobiotic metabolism?
Drug metabolism, sometimes called xenobiotic metabolism, is the process of biotransforming less polar compounds into more polar compounds that can be excreted more easily. Biotransformation typically occurs through a series of enzymatic reactions involving the cytochrome P450 system.
What is xenobiotic detoxification?
In general, xenobiotic detoxification involves the conversion of lipid-soluble substances to water-soluble, excretable metabolites. In Phase I detoxification, the toxin structure is enzymatically altered and rendered unable to interact with lipophilic target sites.
What is a metabolizing enzyme?
Drug metabolizing enzyme s ( DME s) are a diverse group of proteins that are responsible for metabolizing a vast array of xenobiotic chemicals, including drugs, carcinogens, pesticides, pollutants, and food toxicants, as well as endogenous compounds, such as steroids, pros- taglandins, and bile acids (Coon, 2005 ; …
What is the enzyme responsible for hydroxylation of xenobiotics?
CYTOCHROME P450 HYDROXYLATE
ISOFORMS OF CYTOCHROME P450 HYDROXYLATE A MYRIAD OF XENOBIOTICS IN PHASE 1 OF THEIR METABOLISM. The main reaction involved in phase 1 metabolism is hydroxylation, catalyzed by a family of enzymes known as monooxygenases or cytochromes P450. There are at least 57 cytochrome P450 genes in the human genome.
What are xenobiotic components?
INTRODUCTION. Xenobiotic is a term used to describe chemical substances that are foreign to animal life and thus includes such examples as plant constituents, drugs, pesticides, cosmetics, flavorings, fragrances, food additives, industrial chemicals and environmental pollutants.
What causes slow drug metabolism?
Underlying health conditions can also influence your drug metabolic rate. Some conditions at greater risk of this are chronic liver disorders, kidney dysfunction, or advanced heart failure.
What is the function of xenobiotic metabolizing enzymes?
Xenobiotic metabolizing enzymes, important for the metabolism, elimination and detoxification of exogenous agents, are found in most tissues and organs and are distinguished into phase I and phase II enzymes, as well as phase III transporters.
What are some examples of xenobiotics?
Xenobiotic is a term used to describe chemical substances that are foreign to animal life and thus includes such examples as plant constituents, drugs, pesticides, cosmetics, flavorings, fragrances, food additives, industrial chemicals and environmental pollutants.
Is coffee a xenobiotic?
Yes. Xenobiotics (ie. caffeine) affect liver enzymes and this starts the clock.
Are there any xenobiotic metabolizing enzymes in the lung?
The major xenobiotic metabolizing enzymes, including both phase I and phase II enzymes, have been detected in animal and human lung tissues.
Which is a major target organ for xenobiotic metabolizing enzymes?
Xenobiotic-metabolizing enzymes in human lung Human lung is a major target organ for all inhaled drugs, environmental toxicants and carcinogens. Recent hypotheses suggesting a role for environmental toxicants in the pathogenesis of lung diseases, such as lung cancer and chronic obstructive pulmonary disease have stimulated interest in research …
What is role of cytochrome P450 in xenobiotic metabolism?
Xenobiotic metabolizing enzymes including cytochromes P450 (CYP), play a key role in biotransformation, metabolism and/or the detoxification of foreign compounds [Gueguen et al 2006b]. Phase I enzymes (essentially the cytochromes P450), so-called functionalizing enzymes, essentially catalyse oxido-reduction and hydrolysis reactions.
Which is the Phase 2 enzyme in xenobiotics?
Phase II enzymes (glutathion-S-transferases or GST, UDP glucuronosyl transferases or UGT…), so-called conjugating enzymes, catalyse conjugation reactions.