Metabolism of bilirubin and its biological properties

This overview is focused on the bilirubin molecule and its important biological properties. For a long time, bilirubin has been considered a waste product of heme catabolism with potential toxic effects especially on the central nervous system. However, bilirubin has attracted the attention of scientists because of its protective effects. Mildly elevated plasma bilirubin levels are associated with antioxidant, anti-inflammatory and immunomodulatory effects observed in patients with diseases associated with oxidative stress and chronic inflammation. The exact mechanisms of protective action of bilirubin have not been fully elucidated so far, although understanding of these mechanisms could facilitate the therapeutic use of substances that mildly increase bilirubin levels in the body.