L-Citrulline: Novel Pharmacotherapy to Improve Outcomes in Infants and Children at Risk of Systemic or Pulmonary Vascular Disease

Infants and children suffering from a variety of heart, lung, and blood disorders are known to be at risk of developing systemic or pulmonary vascular disease. Despite progress made in clinical care, these patients continue to experience high morbidity and mortality. There is evidence that an impairment in the L-arginine-NO signaling pathway is involved in the pathogenesis of many of the vascular disorders afflicting children. By boosting NO production, L-citrulline, the amino acid precursor of the NO substrate L-arginine, has the potential to ameliorate vascular diseases in both the systemic and pulmonary circulations. This review will discuss the current status of the use of L-citrulline as a treatment to improve outcomes in pediatric patients suffering from disorders that place them at risk of developing systemic or pulmonary vascular disease. Future directions and the potential therapeutic use of L-citrulline in vascular diseases not yet under clinical investigation will also be discussed.