a chemical compound foreign to a given biological system. With respect to animals and humans, xenobiotics include drugs, drug metabolites, and environmental compounds such as pollutants that are not produced by the body. In the environment, xenobiotics include synthetic pesticides, herbicides, and industrial pollutants that would not be found in nature.
xen o bi ot ic
1. A pharmacologically, endocrinologically, or toxicologically active substance not endogenously produced and therefore foreign to an organism.
2. Pertaining to association of two animal species, usually insects, in the absence of a dependency relationship, as opposed to parasitism.
[xeno- + G. bios, life + -ic]
Not a natural component of a particular organism or biological system. Used of chemical compounds.
A xenobiotic chemical, such as a pesticide.
Etymology: Gk, xenos, strange, bios, life
a chemical compound foreign to a given biological system. With respect to animals and humans, xenobiotics include drugs, drug metabolites, and environmental compounds, such as pollutants that are not produced by the body. In the environment, xenobiotics include synthetic pesticides, herbicides, and industrial pollutants that would not be found in nature.
xen o bi ot ic
A pharmacologically, endocrinologically, or toxicologically active substance not endogenously produced and therefore foreign to an organism.
a chemically synthesized compound that is found in the natural environment, but that does not normally occur in nature. Examples include pesticides, dyes, industrial pollutants. Such compounds may be structurally related to natural compounds and may be degraded slowly by the ENZYMES that degrade the natural counterparts. Others may be structurally unrelated to any known natural compound and their degradation occurs very slowly if at all. Xenobiotics generally persist in environments where microorganisms capable of their degradation do not naturally occur.
xen o bi ot ic
Pharmacologically, endocrinologically, or toxicologically active substance not endogenously produced and therefore foreign to an organism.
any substance, harmful or not, that is foreign to the animal’s biological system.
the principal mechanism for maintaining homeostasis during exposure to small foreign molecules such as drugs and toxins; the process deals with foreign chemicals which are too small for processing by the immune system; composed of enzyme systems evolved to render xenobiotics easily excreted, mainly in the liver; enzymic reactions classified as Phase I (add to or expose functional chemical groups; includes cytochrome P-450 monooxygenases) and Phase II (glucuronidation, conjugation and other reactions producing a large increase in water solubility to promote excretion). Cats lack the capacity for glucuronidation, making them more susceptible to certain poisonings, e.g. acetaminophen (paracetamol).
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Relative to unselected cells, AHR-positive cells showed a time-dependent decrease of expression of GO categories involved in a) cardiac differentiation and morphogenesis, b) increasingly lower expression of categories involved in WNT (wingless-related MMTV integration site 3A) signaling and regulation of gastrulation, c) gametogenesis, and d) high levels of expression of genes involved in drug and xenobiotic metabolism (Figure 2B; see also Supplemental Material, Table S3).
Upon removal of the xenobiotic. the electrons produced during the detoxification of mono-oxygenases cytochrome P450  will react with oxygen .
Candidate genes were selected based on their known or suspected role in crustacean immune or stress responses, endocrine signaling, or xenobiotic metabolism.
1: Examples of reactions involved in the modification of xenobiotic compounds and, in some cases, endogenous metabolites.
The present data can help to explore the relationship of xenobiotic metabolizing enzymes with disease risk and drug effects in Indian population.
NAT-dependent acetylation of AAs leads mainly to xenobiotic detoxication but also to bioactivation.
This is followed by an introduction to the all-important issue of the consequences of drug and xenobiotic metabolism, providing an initial overview of pharmacokinetic, pharmacological and toxicological consequences.
Sigma-Aldrich plans to knock-out genes for critical xenobiotic sensors-such as PXR and CAR-and drug transporters-including BSEP, OATP1B1, and OATP1B3-that regulatory agencies have highlighted for possible analysis.
The human pregnane X receptor (PXR) is a nuclear hormone receptor (NHR) that regulates the transcription of genes involved in xenobiotic metabolism and excretion.
This book, in amalgamating the know-how of more than 1200 peer-reviewed literature into extensive tables, provides an overview of nearly all known xenobiotic mediated endocrine effects in fish.
Linehan has fifteen years of experience in the field, holding previous positions at XenoBiotic Laboratories and WIL Research Laboratories, where he set up quantitative whole body autoradiography (QWBA) capabilities and conducted mass balance/tissue distribution studies.
The authors conclude that weak hormonally active xenobiotic agents had small associations with pubertal development, mainly among those agents detected at the highest concentrations.