What are xenobiotics and their examples?
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.
Where are xenobiotics metabolism?
Most of these compounds are subject to metabolism, mainly in the liver. While the metabolism of xenobiotics is generally considered to be a process of detoxification, sometimes the metabolites of compounds that are themselves inert or harmless are biologically active.
What are 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 xenobiotic means?
Xenobiotics have been defined as chemicals to which an organism is exposed that are extrinsic to the normal metabolism of that organism. Without metabolism, many xenobiotics would reach toxic concentrations. Most metabolic activity inside the cell requires energy, cofactors, and enzymes in order to occur.
What is phases of xenobiotic metabolism?
The metabolism of xenobiotics is often divided into three phases:- modification, conjugation, and excretion. These reactions act in concert to detoxify xenobiotics and remove them from cells.
What is the function of xenobiotics?
The xenobiotic metabolizing enzymes 2 have a primary role in protection against harmful insult from the environment. Playing a key role in the metabolism and elimination of potentially toxic compounds, any change in their regulation, expression and/or their activity may have harmful effects on the body.
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 are the sources of xenobiotics?
Xenobiotics in the environment Some of the main sources of pollution and the introduction of xenobiotics into the environment come from large industries such as pharmaceuticals, fossil fuels, pulp and paper bleaching and agriculture.
What are the 3 phases of metabolism?
The metabolism of xenobiotics is often divided into three phases:- modification, conjugation, and excretion.
What are the two phases of metabolism called?
Two phases of metabolism are anabolism and catabolism. The sum of the physical and chemical processes by which living organized substance is built up and maintained (anabolism). Large molecules are broken down into smaller molecules to make energy available to the organism (catabolism).
What are examples of metabolism?
The chemical processes that let you stay alive are an example of metabolism. The rate at which you burn fat and calories you consume is an example of metabolism. The processing of a specific substance within a living cell or organism.
Where does Phase 1 xenobiotic metabolism occur?
Although Phase I drug metabolism occurs in most tissues, the primary and first pass site of metabolism occurs during hepatic circulation. Additional metabolism occurs in gastrointestinal epithelial, renal, skin, and lung tissues.
What are three examples of metabolism?
There are three components to metabolism: basal metabolic rate (BMR), thermogenesis, and physical activity (including leisure activities). BMR is the amount of energy the body needs to maintain normal function.