Description | 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. 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 - oxidoreductase. 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. Because of its ability to transfer electrons and therefore act as an antioxidant, Coenzyme Q has become a valued dietary supplement. CoQ10 has been widely used for the treatment of heart disease (especially heart failure), gum diseases, and also breast cancer. The benzoquinone portion of Coenzyme Q10 is synthesized from amino acids, while the isoprene sidechain is synthesized from acetyl CoA through the mevalonate pathway. The mevalonate pathway is used for the first steps of cholesterol biosynthesis. |