Circulating bilirubin and defense against kidney disease and cardiovascular mortality: mechanisms contributing to protection in clinical investigations

Am J Physiol Renal Physiol. 2014 Jul 15;307(2):F123-36. doi: 10.1152/ajprenal.00039.2014. Epub 2014 Apr 23.

Abstract

Unconjugated bilirubin is an endogenous circulating antioxidant, bound to albumin, and therefore is retained in the vascular compartment. Bilirubin has well-documented neurotoxic effects in infants; however, current evidence indicates mildly elevated bilirubin is associated with protection from cardiovascular disease and all-cause mortality in adults. Recent clinical studies show mildly elevated bilirubin is associated with protection from kidney damage and dysfunction, in addition to cardiovascular events and all-cause mortality in patients undergoing hemodialysis. This is the first review to examine the clinical evidence and summarize the potential mechanisms of action that link bilirubin to protection from kidney damage, subsequent kidney failure, and dialysis-related mortality. With this understanding, it is hoped that new therapies will be developed to prevent renal dysfunction and mortality from cardiovascular disease in at-risk individuals.

Keywords: NADPH oxidase; all-cause mortality; antioxidant; bile pigment; hemodialysis; tetrapyrrole.

Publication types

  • Review

MeSH terms

  • Animals
  • Bilirubin / blood*
  • Biomarkers / blood
  • Cardiovascular Diseases / blood*
  • Cardiovascular Diseases / mortality
  • Cardiovascular Diseases / physiopathology
  • Cardiovascular Diseases / prevention & control
  • Disease Progression
  • Humans
  • Kidney / metabolism*
  • Kidney / physiopathology
  • Kidney Diseases / blood*
  • Kidney Diseases / mortality
  • Kidney Diseases / physiopathology
  • Kidney Diseases / therapy
  • Renal Dialysis / adverse effects
  • Renal Dialysis / mortality
  • Risk Assessment
  • Risk Factors
  • Treatment Outcome
  • Up-Regulation

Substances

  • Biomarkers
  • Bilirubin