Pyruvate metabolism is regulated by multiple enzymes in mitochondria, and any abnormality in genes encoding proteins may lead to various diseases such as cancer, heart failure, and neurodegeneration.51 Under the action of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT), lactate and valine are converted to pyruvate and pass through pyruvate metabolism into the TCA cycle. Here, GPT is linked to heart failure.