indication

For nutritional supplementation, also for treating dietary shortage or imbalance

pharmacology

Pyruvic acid or pyruvate is a key intermediate in the glycolytic and pyruvate dehydrogenase pathways, which are involved in biological energy production. Pyruvate is widely found in living organisms. It is not an essential nutrient since it can be synthesized in the cells of the body. Certain fruits and vegetables are rich in pyruvate. For example, an average-size red apple contains approximately 450 milligrams. Dark beer and red wine are also rich sources of pyruvate. Recent research suggests that pyruvate in high concentrations may have a role in cardiovascular therapy, as an inotropic agent. Supplements of this dietary substance may also have bariatric and ergogenic applications.

mechanism of action

Pyruvate serves as a biological fuel by being converted to acetyl coenzyme A, which enters the tricarboxylic acid or Krebs cycle where it is metabolized to produce ATP aerobically. Energy can also be obtained anaerobically from pyruvate via its conversion to lactate. Pyruvate injections or perfusions increase contractile function of hearts when metabolizing glucose or fatty acids. This inotropic effect is striking in hearts stunned by ischemia/reperfusion. The inotropic effect of pyruvate requires intracoronary infusion. Among possible mechanisms for this effect are increased generation of ATP and an increase in ATP phosphorylation potential. Another is activation of pyruvate dehydrogenase, promoting its own oxidation by inhibiting pyruvate dehydrogenase kinase. Pyruvate dehydrogenase is inactivated in ischemia myocardium. Yet another is reduction of cytosolic inorganic phosphate concentration. Pyruvate, as an antioxidant, is known to scavenge such reactive oxygen species as hydrogen peroxide and lipid peroxides. Indirectly, supraphysiological levels of pyruvate may increase cellular reduced glutathione.

toxicity

Those taking large doses of supplemental pyruvate—usually greater than 5 grams daily—have reported gastrointestinal symptoms, including abdominal discomfort and bloating, gas and diarrhea. One child receiving pyruvate intravenously for restrictive cardiomyopathy died.

biotransformation

In the liver, pyruvate is metabolized via several pathways.

absorption

Pyruvate is absorbed from the gastrointestinal tract from whence it is transported to the liver via the portal circulation.