Pantethine

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Pantethine (Bis-pantethine) or "Co-enzyme pantethine" is a dimeric form of vitamin B5, 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 is less stable than pantothenic acid and tends to decompose over time if it is not kept refrigerated, so most vitamin B5 supplements are in the form of calcium pantothenate.


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N-[2-[2-[2-[3-(2,4-dihydroxy-3,3-dimethyl-butanoyl)aminopropanoylamino ]ethyldisulfanyl]ethylcarbamoyl]ethyl]-2,4-dihydroxy-3,3-dimethyl-butanamide.

CAS# 16816-67-4

Supplement

Pantethine is available as a dietary supplement. This synthesized molecule is typically sold in units of 300 mg/tablet, with suggested use of 1 to 3 tablets or capsules per day. Label claims are couched in the allowable "Structure:Function" language of dietary supplement claims, as in "Pantethine helps to support healthy blood lipid levels." For dietary supplements the evidence is relatively strong; 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.

Physiological Effects

Although pantethine can serve as a precusor for generation of vitamin B5 (pantothenic acid) this is not thought to be the mechanism of action. Vitamin B5 requirements are on the order of 5 mg/day. Effective pantethine intakes are in the range of 600 to 1200 mg/day. Mega-dosing of vitamin B5 does not have the same lipid consequences as pantethine.

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 sulfer-containing amino acids in liver enzymes involved in the production of cholesterol and triglycerides. Useful reference on mechanism: McCarty MF. Medical Hypotheses 2001;56(3):314-317.