Evaluating the Beneficial and Detrimental Effects of Bile Pigments in Early and Later Life

Abstract

The heme degradation pathway has been conserved throughout phylogeny and allows for the removal of a pro-oxidant and the generation of unique molecules including bile pigments with important cellular functions. The impact of bile pigments on health and disease are reviewed, as is the special circumstance of neonatal hyperbilirubinemia. In addition, the importance of promoter polymorphisms in the UDP-glucuronosyl transferase gene (UGTA1), which is key to the elimination of excess bilirubin and to the prevention of its toxicity, are discussed. Overall, the duality of bile pigments as either cytoprotective or toxic molecules is highlighted.

Effects of Biliverdin Administration on Acute Lung Injury Induced by Hemorrhagic Shock and Resuscitation in Rats

“…BV is converted to bilirubin by BVR in mammalian tissue, and hyperbilirubinemia is associated with a risk of neurological deficit [6]. The 35-mg/kg dose of BV elevated serum bilirubin levels 1 h after treatment, although the elevated level was not outside the high normal range of <1 mg/dl in this study.…”

“…Bilirubin is considered toxic in high concentrations because it exerts harmful effects on the central nervous system [6]. The anti-oxidant activity of bilirubin was shown in for the first time in the 1980s [7].…”

The Role of Bile Pigments in Health and Disease: Effects on Cell Signaling, Cytotoxicity, and Cytoprotection

“…The effects of bilirubin vary with age (Dennery, 2012), and metalloporphyrins have been suggested to reduce excessive hyperbilirubinemia and brain damage in newborns (Schulz et al, 2012). …”

“…The role of glial cells and inflammation in bilirubin neurotoxicity (Brites, 2012 ) and the transport and metabolism of bilirubin at blood-brain interfaces and neural cells (Gazzin et al, 2012 ) illustrate the complex nature of bilirubin-induced brain damage. The effects of bilirubin vary with age (Dennery, 2012 ), and metalloporphyrins have been suggested to reduce excessive hyperbilirubinemia and brain damage in newborns (Schulz et al, 2012 ).…”

The role of bile pigments in health and disease: effects on cell signaling, cytotoxicity and cytoprotection

“…The effects of bilirubin vary with age (Dennery, 2012), and metalloporphyrins have been suggested to reduce excessive hyperbilirubinemia and brain damage in newborns (Schulz et al, 2012).…”