Complex sentence: Coenzymes are usually continuously regenerated and their concentrations maintained at a steady level inside the cell: for example, NADPH is regenerated through the pentose phosphate pathway and "S"-adenosylmethionine by methionine adenosyltransferase.
Split into simpler sentences: Coenzymes are usually continuously regenerated and their concentrations maintained at a steady level inside the cell. For example, NADPH is regenerated through the pentose phosphate pathway and "S"-adenosylmethionine by methionine adenosyltransferase.