Coenzyme Q (CoQ), also known as ubiquinone or ubiquinol, is a biologically active quinone with an isoprenoid side chain, related in structure to vitamin K and vitamin E. A quinone or benzoquinone is generally defined as an aromatic benzene molecule containing a double ketone functional group. ... Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ... Vitamin K denotes a group of 2-methilo-naphthoquinone derivatives. ... Tocopherol, or Vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. ...

History

Coenzyme Q was first discovered in 1957 by professor F. L. Crane and colleagues at the University of Wisconsin Enzyme Institute. In 1958, its chemical structure was reported by Dr. D.E. Wolf and a research group at Merck Laboratories led by Dr. Karl Folkers. 1957 (MCMLVII) was a common year starting on Tuesday of the Gregorian calendar. ... The University of Wisconsin–Madison is a public university located in Madison, Wisconsin. ... 1958 (MCMLVIII) was a common year starting on Wednesday of the Gregorian calendar. ... Merck may refer to: Merck & Co. ...

Chemical properties

The oxidized structure of CoQ, or Q, is given here:

structure of ubiquinone 3. ...

The various kinds of Coenzyme Q can be distinguished by the number of isoprenoid side chains they have. The most common CoQ in human mitochondria is Q₁₀. The image above has three isoprenoid units and would be called Q₃. Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ... The term Side chain can have different meanings depending on the context: In chemistry and biochemistry a side chain is a part of a molecule attached to a core structure. ... In cell biology, a mitochondrion is an organelle found in the cells of most eukaryotes. ... Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ...

If Coenzyme Q is reduced by one equivalent, the following structure results, a ubisemiquinone, and is denoted QH. Note the free radical on one of the ring oxygens. In chemistry free radicals are uncharged atomic or molecular species with unpaired electrons or an otherwise open shell configuration. ...

structure of ubisemiquinone 3. ...

If Coenzyme Q is reduced by two equivalents, the compound becomes a ubiquinol, denoted QH₂:

structure of ubiquinol 3. ...

Biochemical role

CoQ is found in the membranes of endoplasmic reticulum, peroxisomes, lysosomes, vesicles and notably the inner membrane of the mitochondrion where it is an important part of the electron transport chain; there it passes reducing equivalents to acceptors such as Coenzyme Q - cytochrome c reductase: A biological membrane or biomembrane is a membrane which acts as a barrier within or around a cell. ... The endoplasmic reticulum or ER (endoplasmic means within the cytoplasm, reticulum means little net) is an organelle found in all eukaryotic cells. ... Basic structure of a peroxisome Peroxisomes are ubiquitous organelles in eukaryotes that function to rid the cell of toxic substances. ... Lysosomes are organelles that contain digestive enzymes (acid hydrolases) to digest macromolecules. ... In cell biology, a vesicle is a relatively small and enclosed compartment, separated from the cytosol by at least one lipid bilayer. ... In cell biology, a mitochondrion (plural mitochondria) (from Greek mitos thread + khondrion granule) is an organelle, variants of which are found in most eukaryotic cells[1]. Mitochondria are sometimes described as cellular power plants, because their primary function is to convert organic materials into energy in the form of ATP... The Electron Transport Chain. ... CoQ Cytochrome c reductase The Coenzyme Q - cytochrome c reductase complex, sometimes called the cytochrome bc1 complex, and at other times Complex III, is the third complex in the electron transfer chain (PDB 1KYO, EC 1. ...

CoQH₂+ 2 Fe⁺³-cytochrome c → CoQ + 2 Fe⁺²-cytochrome c

CoQ is also essential in the formation of the apoptosome along with other adapter proteins. The loss of trophic factors activates pro-apoptotic enzymes, causing the breakdown of mitochondria. The apoptosome is a big multi-protein structure formed in the process of apoptosis. ... A cell undergoing apoptosis. ...

Supplementation

Because of its ability to transfer electrons and therefore act as an antioxidant, Coenzyme Q has become a valued dietary supplement. An antioxidant is a chemical that reduces the rate of particular oxidation reactions in a specific context, where oxidation reactions are chemical reactions that involve the transfer of electrons from a substance to an oxidising agent. ... It has been suggested that Biologically active dietary supplement be merged into this article or section. ...

Young people are able to make Q₁₀ from the lower numbered ubiquinones such as Q₆ or Q₈. The sick and elderly may not be able to make enough, thus Q₁₀ becomes a vitamin later in life and in illness. Vitamins are nutrients required for essential metabolic reactions in the body [1]. Vitamins can act both as catalysts and participants in the chemical reaction. ...

Supplementation of Coenzyme Q₁₀ has been found to have a beneficial effect on the condition of some sufferers of migraine headaches, and is a common component of the "mito cocktail" used to treat mitochondrial disorders and other metabolic disorders. It is also being investigated as a treatment for cancer, and as relief from cancer treatment side effects. Mitochondrial diseases are a group of disorders relating to the mitochondria, the organelles that are the powerhouses of the eukaryotic cells that comprise higher-order lifeforms (including humans). ... A metabolic disorder is a medical disorder which affects the production of energy within individual human (or animal) cells. ... When normal cells are damaged beyond repair, they are eliminated by apoptosis. ...

Recent studies have shown that the antioxidant properties of Coenzyme Q₁₀ benefit the body and the brain. Some of these studies indicate that Coenzyme Q₁₀ protects the brain from neurodegenerative disease such as Parkinsons and also from the damaging side effects of a transient ischemic attack (stroke) in the brain. Comparative brain sizes In animals, the brain, or encephalon (Greek for in the head), is the control center of the central nervous system. ... Parkinsons disease (PD; paralysis agitans) is a neurodegenerative disease of the substantia nigra (an area in the basal ganglia of the brain). ...

Another recent study shows a survival benefit after cardiac arrest if coenzyme Q₁₀ is administered in addition to commencing active cooling (to 32–34 degrees Celsius).

Synthesis and its inhibition by statins and beta blockers

The isoprene sidechain of Coenzyme Q₁₀ is synthesized from acetyl CoA by a series of enzymatic reactions, while the benzoquinone portion is synthesized from amino acids. Isoprene is a common synonym for the chemical compound 2-methyl-1,3-butadiene. ... Categories: Biochemistry stubs | Thiols ... Quinone is generally defined as an aromatic beneze molecule containing a double ketone functional group. ...

Coenzyme Q₁₀ shares a common biosynthetic pathway with cholesterol. Isopentenyl pyrophosphate and its isomer, dimethylallyl pyrophosphate, are linked alternatingly in polyprenyl chains, which are also called isoprenes. The 15-carbon isoprene chain is farnesyl pyrophosphate, which is a precursor to cholesterol, while the 50-carbon isoprene chain forms the sidechain of coenzyme Q₁₀. Cholesterol is a sterol (a combination steroid and alcohol) and a lipid found in the cell membranes of all body tissues, and transported in the blood plasma of all animals. ... Chemical structure of isopentenyl pyrophosphate. ... Structure of dimethyallyl pyrophosphate Dimethylallyl pyrophosphate (or -diphosphate) (DMAPP) is an intermediate product of both mevalonic acid (MVA) pathway and DOXP/MEP pathway. ... Chemical structure of farnesyl pyrophosphate. ... Cholesterol is a sterol (a combination steroid and alcohol) and a lipid found in the cell membranes of all body tissues, and transported in the blood plasma of all animals. ...

The synthesis of an intermediary precursor of Coenzyme Q₁₀, mevalonate, is inhibited by some beta blockers, blood pressure lowering medication [1], and statins, a class of cholesterol lowering drugs [2]. Statins can reduce serum levels of coenzyme Q₁₀ by up to 40% [3]. Some research suggests the logical option of supplementation with coenzyme Q₁₀ as a routine adjunct to any treatment which may reduce endogenous production of coenzyme Q₁₀, based on a balance of likely benefit against very small risk. [4][5] Mevalonic acid is a key organic compound in biochemistry. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ... Lovastatin, the first statin to be marketed The statins form a class of hypolipidemic agents. ...

External links

• Women’s Health and the Benefits of CoQ10
• Synthesis of Coenzyme Q₁₀ Flow Chart
• An Introduction to Coenzyme Q₁₀
• Vitamin Q - Herbs & Supplements - Drug Library - DrugDigest
• Co-Q₁₀ Energizes the Heart and Brain
• Possible Health Benefits of Coenzyme Q₁₀
• Coenzyme Q₁₀ administration increases brain mitochondrial concentrations and exerts neuroprotective effects
• Study Suggests Coenzyme Q₁₀ Slows Functional Decline in Parkinson's Disease
• Oral coenzyme Q₁₀ administration prevents the development of ischemic brain lesions in a rabbit model of symptomatic vasospasm
• Coenzyme Q₁₀ information and 3D picture