Pyruvate dehydrogenase complex and related mitochondrial alpha-keto acid dehydrogenases (PDC/OADH complexes)

The Pyruvate dehydrogenase complex (PDC) and related mitochondrial alpha-keto acid dehydrogenases (OADHs) are massive multi-enzyme assemblies that play a central role in mitochondrial energy metabolism (UniProt P08559). This group includes PDC, alpha-ketoglutarate dehydrogenase (KGDHC), and branched-chain alpha-keto acid dehydrogenase (BCKDC), all of which share a similar structural organization consisting of three core enzymes: E1, E2, and E3 (StatPearls NBK554444). These complexes catalyze the oxidative decarboxylation of alpha-keto acids to produce acyl-CoA, CO2, and NADH, effectively linking metabolic pathways like glycolysis and amino acid breakdown to the citric acid cycle (PMID: 24599606). Deficiencies in these enzymes are associated with metabolic diseases such as pyruvate dehydrogenase deficiency and maple syrup urine disease, characterized by lactic acidosis and neurological impairment (NIH GARD). In oncology, these complexes are targeted to disrupt the altered metabolic state of cancer cells, while in metabolic diseases, they are modulated to improve glucose oxidation (J. Biol. Chem. 2013). Therapeutic strategies include the use of kinase inhibitors to maintain the complexes in their active, dephosphorylated state or the administration of essential cofactors to boost residual enzyme activity (PubChem CID 299).

Other names

2-oxoacid dehydrogenase complexesMitochondrial alpha-keto acid dehydrogenase complexes2-OADH complexesAlpha-keto acid dehydrogenase complexes

Activation of the complex via inhibition of regulatory kinases (e.g., PDK), inhibition of the complex to disrupt cancer metabolism, or supplementation of essential enzymatic cofactors (thiamine, lipoate).