What is glucuronide conjugate?
Glucuronide conjugate process is perhaps the major and most common route for Phase II metabolism to form water-soluble metabolites. Glucuronide conjugation involves the direct interaction of the drugs and xenobiotics (or its Phase I metabolite) with the cofactor UDP–glucuronic acid (UDPGA) as shown in Fig. 8.2.
Where does glucuronide conjugation occur?
Sites. Glucuronidation occurs mainly in the liver, although the enzyme responsible for its catalysis, UDP-glucuronyltransferase, has been found in all major body organs (e.g., intestine, kidneys, brain, adrenal gland, spleen, and thymus).
What does glucuronide conjugation do?
Conjugation: Glucuronidation and Sulfation It involves the transfer of glucuronic acid from the cofactor UDP-glucuronic acid to functional groups, in particular hydroxyl groups, of the substrates. Lipophilic compounds are thus converted to water-soluble derivates, which are then excreted in bile or urine.
What does glucuronic acid conjugate?
The glucuronic acid conjugates, or “glucuronide conjugates” as they are commonly called, are compounds formed by enzyme-catalysed glucuronidation of drug metabolites that contain either a hydroxyl group (ROH – alcohols; PhOH – phenols) or a carboxyl group (RCO2H – acids).
Why are drugs referred to as xenobiotics?
The term xenobiotic is derived from the Greek words ξένος (xenos) = foreigner, stranger and βίος (bios) = life, plus the Greek suffix for adjectives -τικός, -ή, -όν (-tikos, -ē, -on). Xenobiotics may be grouped as carcinogens, drugs, environmental pollutants, food additives, hydrocarbons, and pesticides.
How is glucuronide formed?
Glucuronidation is a conjugation reaction whereby glucuronic acid, derived from cofactor UDP-glucuronic acid, is covalently linked to a substrate containing a nucleophilic functional group. The resultant metabolite, called a glucuronide, is usually excreted in bile and urine.
How is glucuronide excreted?
MPAG is excreted via bile into the gut where it exhibits a significant entero-hepatic recirculation, with a concomitant second peak in plasma mycophenolic acid concentration 6–12h after dosing.
What is conjugation in drug metabolism?
Conjugation. Glucuronidation, the most common phase II reaction, is the only one that occurs in the liver microsomal enzyme system. Glucuronides are secreted in bile and eliminated in urine. Thus, conjugation makes most drugs more soluble and easily excreted by the kidneys.
What is another name for D Glucaric acid?
D-Glucaric acid, otherwise known as saccharic acid, is the product of oxidizing sugars or polysaccharides with nitric acid.
Is gluconic acid a reducing sugar?
Reducing sugars themselves they oxidize and reduce the other chemicals that is why they are called as reducing sugars. Reducing sugars are always monosaccharides. Means reducing sugars always exist as single molecules. Coming to given options, option B, Gluconic acid.
Are all drugs xenobiotics?
Drugs can be considered a subset of xenobiotics, that is, natural compounds of exogenous origin that may find their way into the human body.
Why are xenobiotics harmful?
Displacement of toxic xenobiotics from plasma proteins can greatly increase the amount of unbound toxicant distributed to target organs or tissue. A wide variety of xenobiotics accumulate in the liver and kidneys, making these organs ideal sites for postmortem sample collection in cases of suspected toxicoses.
What is the role of glucuronide conjugate formation?
Glucuronide conjugate formation is a common metabolic process utilized by numerous organisms, and is called glucuronidation. Glucuronidation plays many important roles in the human body, including often being a critical component of drug metabolism.
Which is the parent of the chemical phenol?
Phenol is an organic hydroxy compound that consists of benzene bearing a single hydroxy substituent. The parent of the class of phenols. It has a role as a disinfectant, an antiseptic drug, a human xenobiotic metabolite and a mouse metabolite. It is a conjugate acid of a phenolate. phenol Computed by LexiChem 2.6.6 (PubChem release 2019.06.18)
How is phenol used in plastics and adhesives?
Used to make plastics, adhesives and other chemicals. Phenol is an organic hydroxy compound that consists of benzene bearing a single hydroxy substituent. The parent of the class of phenols. It has a role as a disinfectant, an antiseptic drug, a human xenobiotic metabolite and a mouse metabolite. It is a conjugate acid of a phenolate. phenol
Which is more enzymatic M6G or M3G glucuronide?
The M6G conjugate has an enzymatic hydrolysis rate similar to that of codeine, and roughly 1/4th that of the M3G glucuronide conjugate.1 Therefore, when developing a method for the cleavage of a wide range of substrates, it is worthwhile to explore conditions that will adequately account for these variations in conjugate hydrolysis rates.