Coenzyme Q 10


Coenzyme Q 10 was first isolated in 1957 and its chemical structure (benzoquinone compound) was determined in 1958. A large amount of laboratory and animal data on coenzyme Q 10 has accumulated since 1962. Research into cellular energy-producing mechanisms that involve this compound was awarded the Nobel Prize in chemistry in 1978. Some of the accumulated data show that in animals, coenzyme Q 10 stimulates animal immune systems, leading to higher antibody levels, greater numbers and/or activities of macrophages and T cells (T lymphocytes), and increased resistance to infection. Coenzyme Q 10 has also been reported to increase IgG ( immunoglobulin G) antibody levels and to increase the CD4 to CD8 T-cell ratio in humans. CD4 and CD8 are proteins found on the surface of T cells, with CD4 and CD8 identifying helper T cells, which stimulates antibody production by B cells, and cytotoxic T cells, respectively;

Interest in coenzyme Q 10 as a therapeutic agent in cancer began in 1961, when a deficiency was noted in the blood of both Swedish and American cancer patients, especially in the blood of patients with breast cancer. A subsequent study showed a statistically significant relationship between the level of plasma coenzyme Q 10 deficiency and breast cancer prognosis. Low blood levels of this compound have been reported in patients with malignancies other than breast cancer, including yeoman, lymphoma, and cancers of the lung, prostate, pancreas, colon, kidney, and head and neck.

Clinical studies from the past three decades also indicate effectiveness of CoQ 10 in improving cardiac functions in patients with cardio-myophathy, congestive heart failure or cardiac malfunctions that follow open heart surgery. CoQ 10 is now an approved indication for congestive heart failure in Japan , Italy , Sweden , Denmark and Canada . CoQ 10 pretreatment also reduced cardio-toxicity of doxorubicin, a powerful anticancer drug known for its cardio-toxicity.

General Information

Coenzyme Q 10 is a benzoquinone compound synthesized naturally by the human body. The "Q" and the "10" in the name refer to the quinone chemical group and the 10 isoprenyl chemical subunits, respectively, that are part of this compound's structure. The term "coenzyme" denotes it as an organic (contains carbon atoms), non-protein molecule necessary for the proper functioning of its protein partner (an enzyme or an enzyme complex). CoQ 10 plays a central role in the body in a process known variously as aerobic respiration, aerobic metabolism, oxidative metabolism, or cell respiration. Through this process, energy for cell growth and maintenance is created inside cells in compartments called mitochondria. Mitochondria are factories inside cells that convert the raw material of carbohydrates, fats and proteins into energy that comes packaged into molecular batteries of ATP, to be transported out without dissipating. Oxygen is utilized in this process of energy generation, hence "cell respiration". CoQ 10 is critically involved in this process of energy production and deficiency of CoQ 10 at the cellular level, however it may happen, is detrimental to life processes.

Coenzyme Q 10 is also used by the body as an endogenousantioxidant. An antioxidant is a substance that protects cells from oxidants, also called free radicals or radical oxygen species. Oxidants are characterized by an unpaired electron present in their molecules, which make them highly unstable therefore reactive trying to become stable by 'stealing' an electron from neighboring molecules. This creates a chain reaction of electron robbing, leaving behind oxidized and damaged membranes, DNA, enzymes etc. Most oxidants in our body can be traced to superoxide radicals, oxygen molecules with an unpaired electron, that are produced in mitochondria as a result of mistakes that take place during energy generating reactions. Despite lethal effects of oxidants that are continuously produced in cells, we can remain alive because our body produces antioxidants that neutralize these oxidants. CoQ 10 in its reduced form, the form usually found in our blood, is capable of donating an electron to unstable radicals and itself remaining stable - a hallmark of an antioxidant. CoQ 10 is fat-soluble and therefore closely associated with cell components that are particularly abundant in lipids, most notably membranes and lipoproteins. By neutralizing unstable radicals, it protects lipids from oxidation, thus maintaining the integrity of membranes and 'nipping-in-the-bud' the development of atherosclerosis

Coenzyme Q 10 is present in most tissues, but the highest concentrations are found in the heart, the liver, the kidneys and the pancreas. The lowest concentration is found in the lungs. Tissue levels of this compound decrease as people age, due to increased requirements, decreased production, or insufficient intake of the chemical precursors needed for synthesis. (In particular vitamin B6 in the form of pyridoxal 5'-phosphate is essential for CoQ 10 biosynthesis) In humans, normal blood levels of CoQ 10 have been defined variably, with reported normal values ranging from 0.30 to 3.84  µg/ mL.

Coenzyme Q 10 is also known as Coenzyme Q(5O), CoQ 10 , CoQ(50), ubiquinone (50), ubiquinol-10 (reduced form) and ubidecarerone. Chemically, CoQ 10 is known as 2, 3-dimethyoxy-5-methyl-6-decaprenyl-1,4-benzoquinone, and its structural formula is:

Coenzyme Q 10




Coenzyme Q 10 is synthesized in most human tissues. The biosynthesis of CoQ 10 involves three major steps: 1) synthesis of the benzoquinone structure from the amino acids, tyrosine or phenylalanine, 2) synthesis of the isoprene side chain from acetyl-coenzyme A (CoA) via the mevalonate pathway, and 3) the joining or condensation of these two structures. The enzyme hydroxymethylglutaryl (HMG)-CoA reductase plays a critical role in the regulation of CoQ 10 synthesis as well as the regulation of cholesterol synthesis.

Food Sources

Coenzyme Q 10 also occurs in the food chain. How much exogenous CoQ 10 contributes to the body store of CoQ 10 is not clear. There is good evidence, however, that dietary CoQ 10 contributes significantly to the body store of CoQ 10; this has been shown in patients receiving total parenteral nutrition that contains no CoQ 10 ; in these patients, CoQ 10 levels dropped by almost 50% within a week. Based on food frequency studies the average dietary intake of CoQ 10 in Denmark was estimated to be 3-5 mg/d. Most people probably have a dietary intake of less than 10 mg/d of CoQ 10 . Rich sources of dietary CoQ 10 include mainly meat, poultry and fish. Other relatively rich sources include soybean and canola oils, and nuts. Fruits, vegetables, eggs, and dairy products are moderate sources of CoQ 10 . Approximately 14-32% of CoQ 10 was lost during frying, but the CoQ 10 content of vegetables and eggs did not change when boiled.

Although food sources can provide modest levels of this valuable nutrient, only supplementation can be effective in providing the amounts necessary for therapeutic benefit. Typical therapeutic dosages can range between 60mg-300mg and upwards depending on the condition . Because of its higher absorption, ENTERIC CoQ 10 can be therapeutically effective at 30mg - 60mg daily (one or two capsules daily)

Pharmacokinetics of CoQ 10 absorption

CoQ 10 is absorbed from the small intestine into the lymphatics; from there it enters the blood. Dietary absorption of CoQ 10 is poor. Well over 60% of an oral dose is excreted in the feces. Furthermore, absorption of CoQ 10 is highly variable and depends not only on food intake but also on the amount of lipids present in the food. Absorption is lower on an empty stomach and greater when taken with food of high lipid content. Upon entering the duodenum, lipids stimulate secretion of bile in which biological detergents, bile acid and phospholipids, are contained. In the presence of detergents, the lipids are broken up into microscopic particles, dramatically increasing the surface area for the pancreatic fat-digesting enzymes, lipases, to work on. After digestion by lipases, fatty acids are freed from all lipids including the detergent phospholipid, lecithin. Lecithin (phosphatidyl choline) then becomes lysolecthin, which is a more powerful detergent than the lecithin it replaces. Lipids, now broken down to their components, cholesterol and fat soluble nutrients such as CoQ 10 are now arranged by the detergents into water soluble aggregates of micelles. Because of micelle formation, lipids and fat soluble nutrients can have an access to the intestinal mucosa by which they are absorbed by passive diffusion. In the blood, CoQ 10 is partitioned into the various lipoprotein particles, including VLDL, LDL and HDL. It takes about three weeks of daily dosing with CoQ 10 to reach maximal serum concentrations, which then plateau with continuous daily dosing. CoQ 10 is distributed to the various tissues of the body and is able to enter the brain. The main elimination of CoQ 10 occurs via bile. Absorption of CoQ 10 may be improved when taken in enteric-coated caplets.

Pharmacokinetics of PhosphadidylCholine Absorption

Phosphatidylcholine sometimes called vitamin B4, is absorbed into the mucosal cells of the small intestine, mainly in the duodenum and upper jejunum, following some digestion by the pancreatic enzyme phospholipase, producing lysophosphatidylcholine (lysolecithin). Reacylation of lysolecithin takes place in the intestinal mucosal cells, reforming phosphatidylcholine, which is then transported by the lymphatics in the form of chylomicrons to the blood. Phosphatidylcholine is transported in the blood in various lipoprotein particles, including very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL) and high-density lipoproteins (HDL); it is then distributed to the various tissues of the body. Some phosphatidylcholine is incorporated into cell membranes.


Coenzyme Q 10 is available without prescription as a dietary supplement in the U.S. and Canada . Supplemental doses for adults range from 30-60 mg/day, although this is considerably higher than normal dietary CoQ 10 intake. Therapeutic doses for adults generally range from 100-300 mg/day. Absorption decreases as the dose increases, and is likely less than 10% in humans. Bioavailability improves somewhat when taken with a fatty meal.

Enerex Botanicals Ltd. has introduced ENTERIC CoQ 10, which is designed to get most efficiently incorporated into micelles in the intestine. Enerex's ENTERIC CoQ 10 comes with pyridoxyl 5' -phosphate plus phosphatidylcholine contained together in an enteric coated caplet, creating the most bioactive form of CoQ 10 yet available. Phosphadidyl-choline is produced by partial enzymatic digestion of soybean lecithin and consists of 50-80% of lysolecithin, a digestion product of lecithin, and the remainder of lecithin. Free fatty acids that are released in the process of digestion have been removed during manufacturing (de-oiled). This is probably one of the best possible formulas in terms of micelle formation. Lysolecithin is a powerful biological detergent produced in the intestine when phosphadidylcholine, a phospholipid secreted in the bile along with bile acid, has been partially digested by pancreatic phospholipase. As a detergent, lysolecithin is more powerful than bile acid or lecithin and is itself very quickly absorbed by the intestinal mucosa. Once absorbed, it gets recombined with fatty acid in the mucosa to once again become phosphadidylcholine. Lysolecithin is a more effective detergent than bile acid or lecithin partly because the micelles it helps form are smaller in size. It is also explained by the greater lysolecithin absorption rate. Lysolecithin absorption is 15 times greater that lecithin absorption. Rapid disappearance of lysolecithin from the micelle in absorption creates a higher concentration of each of the remaining components within the micelles. This results in greater gradient in the concentration of each component across the mucosal cell membranes thus accelerating diffusion of each component into the mucosal cells.

Note: In a study published in the American Journal of Clinical Nutrition in 2005 (vol. 81, no 2, pp 440-444), researchers from the University of North Carolina at Chapel Hill reported that deficiency of choline in both mice and humans was associated with increased levels of homocysteine, increasingly thought to be a risk factor for heart disease.

The Enerex ENTERIC CoQ 10 formula, an instant micelle formula, is one of the most efficient ways of attaining critical micelle concentration - the threshold concentration of micelles that must be reached in the intestine for the absorption of fat and fat-soluble nutrients to proceed. With this formula one is not forced to take a large amount of fat with CoQ 10 just to achieve micelle formation, because you are already provided with the essence of micelles. Besides, free fatty acids are removed (de-oiled) from this formula; it means not only fewer calories but also more efficient absorption of CoQ 10 . A study has demonstrated that micelles containing lysolecithin and fatty acids are less effective that lysolecithin alone in absorption of fatty substance. For those who seek a high absorption rate of CoQ 10 and at the same time seek to restrict fat intake, this formula may be a solution.

Called 'ENTERIC CoQ 10 ' this formula provides 30 mg of CoQ 10 plus 10mg of pyridoxal 5' -phosphate along with 250mg of phosphatidylcholine in an enteric-coated caplet Revolutionary new enteric coating technology using Cellulose Acetate Phthalate provides the most precise delivery system known to ensure that the caplet survives the harsh environment of the stomach and dissolves only in the small intestine. Once the caplet has dissolved in the small intestine, virtually 100% of the CoQ 10 and pyridoxal 5' - phosphate is available for absorption. Traditional oral supplementation of CoQ 10 is poorly absorbed with about 3-5% of the dietary CoQ 10 actually making it to the bloodstream. Some formulas combine CoQ 10 with vitamin E or with other lipids which can increase absorption to about 10%, but still very low when compared to absorption from the small intestine. 30mg of ENTERIC CoQ 10 is equivalent to as much as 300 mg of traditional oral supplements. This has important consequences as CoQ 10 is very expensive and therefore ENTERIC CoQ 10 is the most cost effective, based on bioavailability, form available. Another first for Enerex is the inclusion of pyridoxyl 5' -phosphate in the formula. This is a very expensive nutrient and is rarely used by most formulators because of the cost. However, pyridoxyl 5' -phosphate is essential for the body's metabolism of CoQ 10 , and this nutrient is often deficient, especially in those with CoQ 10 deficiency. To ensure the most effective form of CoQ 10 supplementation, both exogenous and endogenous, ENTERIC CoQ 10 sets a new standard.

For more information, please visit Linus Pauling Institute.