Pantethine

Pantethine (bis-pantethine or co-enzyme pantethine) is a dimeric form of pantothenic acid (vitamin B5). It is composed of two molecules of pantothenic acid linked by cysteamine bridging groups. The monomer of this compound is known as pantetheine and is an intermediate in the production of Coenzyme A by the body. Pantethine is considered the more biologically active form of vitamin B5, but it is less stable, decomposing over time if it is not kept refrigerated. Most vitamin B5 supplements are therefore in the form of calcium pantothenate, a salt of pantothenic acid.

Dietary supplementation
Pantethine is available as a dietary supplement because of evidence of its health benefits. In multiple clinical trials of patients with elevated cholesterol and triglycerides, total and LDL cholesterol were decreased by 12%, triglycerides decreased by 18%, and HDL cholesterol was increased by 9%. These clinical trials were conducted with daily intakes ranging from 600 to 1200 mg/day. Within this dose range there is no evidence of a dose-effect relationship, i.e. changes in lipid concentrations overlapped across the range of doses. Direct dose-response evidence is not available because no trial tested more than one dose. A few trials tested 300 mg/day with more modest but still statistically significant results.

Further carefully controlled trials of 600 and 900 mg/d doses have shown statistically significant lowering of LDL cholesterol in individuals with greatly or moderately elevated levels of blood lipids.

Physiological effects
Although pantethine can serve as a precursor for generation of vitamin B5, this is not thought to be the mechanism of action. Vitamin B5 requirements are on the order of 5 mg/day.

Two mechanisms of action are proposed for pantethine. In the first, pantethine serves as the precursor for synthesis of coenzyme A. In the second, pantethine is converted to two pantetheine molecules which are in turn metabolized to form two pantethenic acid and two cysteamine molecules. Cysteamine is theorized to bind to and thus inactivate sulfur-containing amino acids in liver enzymes involved in the production of cholesterol and triglycerides.