Calcium Pantothenate, Pantothenic acid, Vitamin B5
Vitamin B5 is also known as pantothenic acid or calcium pantothenate. This is a water soluble vitamin which is found in the cells. Vitamin B5 is produced in the intestines by bacteria and is known to place a role on preventing depression. Vitamin B5 is necessary for the release of energy from carbohydrates, the synthesis and degradation of fatty acids and other acetylation reactions.
This vitamin is also required for the production of steroid hormones, the adrenal glands’ production of hormones and nervous system function. Vitamin B5 is required to gain resistance to stress, shock and allergies, plus protection against radiation-caused cellular damage. Vitamin B5 has other uses including being required for carbohydrate, fat and protein metabolism, cholesterol and fatty acids, skin health, and decreasing side effects of certain drugs.
Pantothenic acid comes in three forms, and it is alternately known as vitamin B5, panthenol and calcium pantothenate. Pantothenic acid is integral to many of the activities of enzymes in the human body. It is necessary for the manufacture of energy from both sugars and fats in the system as well as the utilization of other vitamins. Pantothenic acid is also essential to the manufacture of fats, corticosteroids and the sex hormones, estrogen, progesterone and testosterone. It is also integral to the proper functioning of the adrenal glands and nervous system as well as for normal growth and development throughout the human body.
The dietary sources for pantothenic acid are vast and varied. Brewers yeast and wheat germ are good sources, as is royal jelly a substance often touted mostly as a beauty aid but which is also rich in this vitamin. Pantothenic acid can also be found in almost all vegetables, as well as cereals. It is is just about every meat product and pantothenic acid can be found in abundance in liver, kidney, heart, and fish as well as egg yolks.
Pantothenic acid, a member of the B-vitamin family, is an essential nutrient in human nutrition. It is sometimes referred to as vitamin B5. Pantothenic acid is involved in a number of biological reactions, including the production of energy, the catabolism of fatty acids and amino acids, the synthesis of fatty acids, phospholipids, sphingolipids, cholesterol and steroid hormones, and the synthesis of heme and the neurotransmitter acetylcholine. It also appears to be involved in the regulation of gene expression and in signal transduction. Roger J. Williams, the discoverer of pantothenic acid and a scientist who pioneered the use of nutrients for the prevention and treatment of disease, thought that pantothenic acid might be helpful in the management of certain medical disorders, such as rheumatoid arthritis.
The principal biologically active forms of pantothenic acid are coenzyme A (CoA) and acyl carrier protein (ACP). In both CoA and ACP, the business center of the molecule is the pantothenic acid metabolite 4'-phosphopantetheine. Coenzyme A is comprised of 4'-phosphopantetheine linked by an anhydride bond to the nucleotide adenosine 5'-monophosphate. 4'-Phosphopantetheine itself is comprised of pantothenic acid linked at one end, via an amide bond, to beta-mercaptoethylamine, derived from L-cysteine, and at the other end to a phosphate group. The sulfhydryl group of 4'-phosphopantetheine, which is the business end of the coenzyme, forms thioesters with acyl groups producing acyl-CoA derivatives, including acetyl-CoA.
Acetyl-CoA is produced via beta-oxidation of fatty acids, via the metabolism of carbohydrates—glucose 6-phosphate to pyruvate to acetyl-CoA—and via the catabolism of amino acids. Acetyl-CoA has a number of metabolic opportunities. It is metabolized in the tricarboxylic acid cycle to produce carbon dioxide, water and energy. It can also be metabolized to fatty acids, cholesterol and steroid hormones. Acetyl-CoA also participates in a number of acetylation reactions, including the formation of acetylcholine, melatonin, N-acetylglucosamine, N-acetylgalactosamine and N-acetylneuraminic acid. Finally, acetyl-CoA is involved in the acetylation of proteins and peptides. Histone acetylation is an epigenetic mechanism of gene regulation. In general, chromatin fractions enriched in actively transcribed genes are also enriched in highly acetylated core histones, whereas silent genes are associated with nucleosomes with a low level of acetylation. Nucleosomes are the fundamental units of chromosomes.
The other major form of pantothenic acid is acyl carrier protein or ACP. Acyl carrier protein (ACP) functions as a coenzyme in the fatty acid synthetase complex which is central to the de novo synthesis of fatty acids. The prosthetic group of acyl carrier protein is again, 4'-phosphopantetheine. 4'-Phosphopantetheine binds to acyl carrier protein via a phosphodiester linkage to a serine residue of acyl carrier protein. The function of ACP in fatty acid synthesis is analogous to that of coenzyme A in the beta-oxidation of fatty acids. ACP serves as an anchor to which the acyl intermediates are esterified. The acyl intermediates are esterified to the sulfhydryl group of 4'-phosphopantetheine. 4'-Phosphopantetheine is added to ACP in a posttranslational modification reaction which is catalyzed by a transferase enzyme acting on CoA. In the case of coenzyme A, the sulfhydryl groups are also esterified to acyl groups, such as the acetyl group. However, the 4'-phosphopantetheine part of the structure is not esterified to a serine residue in a protein (ACP), but is bound to the nucleotide adenosine 5'-monophosphate.
In addition to acetyl-CoA, other forms of CoA also play important biological roles. Malonyl-CoA supplies two-carbon units for the synthesis of fatty acids up until palmitic acid, and succinyl-CoA reacts with delta-aminolevulinic acid in the first reaction of heme biosynthesis. Myristoyl-CoA, derived from the 14-carbon saturated fatty acid myristic acid, is involved in the myristoylation of proteins; palmitoyl-CoA is involved in the palmitoylation of proteins, and farnesyl-CoA and geranylgeranyl-CoA are involved in protein isoprenylation. Protein isoprenylation, myristoylation and palmitoylation appear to play roles in signal transduction, among other biological activities.
The principal supplemental form of pantothenic acid is calcium D-pantothenate (D-calcium pantothenate). This marketed supplement is usually made synthetically. Dexpanthenol, the corresponding alcohol of pantothenic acid is also available. Dexpanthenol is a synthetic form which is not found naturally. Dexpanthenol is converted to pantothenic acid in the body, and therefore can be considered a provitamin form of pantothenic acid. Dexpanthenol is used topically to promote wound healing. It is also used in various cosmetic products.
In addition to being known as vitamin B5, pantothenic acid is also known as D(+)-pantothenic acid, D-pantothenic acid, D (+)-N-(2,4-dihydroxy-3 , 3-dimethylbutyryl)-beta-alanine and (R)-N-(2,4-dihydroxy-3,3-dimethyl-1-oxobutyl)-beta-alanine. D-pantothenic acid is the biologically active enantiomer of the vitamin and is comprised of beta-alanine and a dihydroxy acid called pantoic acid. Its molecular formula is C9H17NO5, its molecular weight is 219.24.
Pantothenic acid and its derivatives, 4'-phosphopantothenic acid, pantothenol and pantethine, have been shown, in vitro, to protect cells against lipid peroxidation. This protective effect does not appear to be due to the scavenging of the reactive oxygen species by pantothenic acid. It is thought that the antioxidant effect of pantothenic acid is due to its stimulation of increased cellular levels of coenzyme A. Coenzyme A may facilitate removal of lipid peroxides by increasing mobilization of fatty acids, and promote repair of plasma membranes by activating phospholipid synthesis. Pantothenic acid has also been shown to increase levels of cellular reduced glutathione. The mechanism by which pantothenic acid increases glutathione levels is unknown. However, increased levels of glutathione may play a large role in the protective effect of pantothenic acid against peroxidative damage of cell membranes.
There is some evidence that pantothenic acid may be helpful in the management of some with rheumatoid arthritis. The mechanism of this putative effect is unclear. Activated granulocytes play a role in the inflammatory response by production of reactive oxygen species. Pantothenic acid, in the form of calcium D-pantothenate, was found to significantly inhibit the release of myeloperoxidase from granulocytes in vitro, as well as to inhibit the production of reactive oxygen species by these cells. This effect of pantothenic acid as well as the antioxidant effect of the vitamin discussed above, may account, in part, for the putative action of pantothenic acid in rheumatoid arthritis.
Pantothenic acid has been shown to accelerate wound healing in experimental animals. The mechanism of the putative wound healing effect of pantothenic acid is unclear. In human dermal fibroblasts in culture, calcium D-pantothenate was demonstrated to accelerate the wound healing process by increasing the number of cells migrating into a wounded area, as well as their mean migration speed. Dexpanthenol (pantothenol), the corresponding alcohol of pantothenic acid, is used topically for the treatment of various minor skin disorders and to promote wound healing. Topical dexpanthenol has been found to improve stratum corneum hydration, reduce tranepidermal water loss and to stabilize the epidermal barrier function. The putative wound healing activity of pantothenic acid, may also be accounted for, in part, by its possible antiinflammatory activity.
Synonyms: Calcium D-(+)-Pantothenate; Vitamin B-5; Pantothenic Acid, Calcium Salt
CAS No.: 137-08-6
Molecular Weight: 476.54
Chemical Formula: (HOCH2C(CH3)2CHOHCONHCH2CH2COO)2Ca
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