Lipoic acid works synergistically with which pair of vitamins for cellular energy production?

• A. Riboflavin and Pantothenic acid
• B. Biotin and Cobalamin
• C. Folate and B6
• D. Thiamin and Niacin

Answer: (D)

Lipoic acid serves as a cofactor in mitochondrial energy production, especially in the pyruvate dehydrogenase complex that links glycolysis to the TCA cycle. In this complex, thiamin provides the thiamin pyrophosphate (TPP) needed for the decarboxylation step, and niacin supplies NAD+ as the main electron carrier for the redox reactions. Lipoic acid works alongside these cofactors to facilitate the transfer of acetyl groups and the regeneration of active enzyme sites, keeping the energy-producing cycle moving. While other vitamins like riboflavin and pantothenic acid are involved in related parts of the energy machinery, the pair most directly synergistic with lipoic acid in cellular energy production centers on thiamin and niacin. The other option groupages reflect different metabolic roles, not the primary PDH-linked energy production pathway.