Coenzyme Q{-1}{-0} is a fat-soluble, vitamin-like substance that works with other enzymes, particularly in the mitochondria, the “powerhouse” of the cell, to make energy. It also acts as an antioxidant, mopping up “free radicals” that can damage cells, said Douglas Wallace, a geneticist who directs the Center for Molecular and Mitochondrial Medicine and Genetics at the University of California, Irvine.