Pyruvate is the end product of glycolysis, which is used and synthesized by many metabolic pathways. In energy generation, it can be either converted to lactate, when the oxygen is not sufficient, or broken down to water and carbon dioxide in the presence of oxygen, generating large amounts of ATP.
Pyruvate, which is a natural metabolic fuel and antioxidant in myocardium and other tissues, exerts a variety of cardioprotective actions when provided at supraphysiological concentrations. Pyruvate increases cardiac contractile performance and myocardial energy state, bolsters endogenous antioxidant systems, and protects myocardium from ischemia-reperfusion injury and oxidant stress.
The Pyruvate Dehydrogenase Complex and Kreb's Cycle explanation ( Video )