Products of heme oxygenase and their potential therapeutic applications.
Heme oxygenase 1 (HO-1) is induced in response to cellular stress and is responsible for converting the prooxidant heme molecule into equimolar quantities of biliverdin (BV), carbon monoxide (CO), and iron. BV is then converted to bilirubin (BR) by the enzyme biliverdin reductase. Experimental evidence suggests that induction of the HO system is an important endogenous mechanism for cytoprotection and that the downstream products of heme degradation, CO, BR, and BV, may mediate these powerful beneficial effects. These molecules, which were once considered to be toxic metabolic waste products, have recently been shown to have dose-dependent vasodilatory, antioxidant, and anti-inflammatory properties that are particularly desirable for tissue protection during organ transplantation. In fact, recent work has demonstrated that administration of exogenous CO, BR, or BV may offer a simple, inexpensive method to substitute for the cytoprotective effects of HO-1 in a variety of clinically applicable models. This review will attempt to summarize the relevant biochemical and cytoprotective properties of CO, BR, and BV, and will discuss emerging studies involving the therapeutic applications of these molecules in the kidney and other organ systems.
Kirkby
Kristin A
KA
The Comparative Nephrology and Transplantation Laboratory, Dept. of Small Animal Clinical Sciences, Veterinary Medical Teaching Hospital, PO Box 100126, Univ. of Florida, Gainesville, FL 32610-0126, USA.
Adin
Christopher A
CA
D000328:Adult; D001664:Biliverdine / Q000378:metabolism / Q000627:therapeutic use; D002248:Carbon Monoxide / Q000378:metabolism; D006418:Heme / Q000378:metabolism* / Q000627:therapeutic use; D051547:Heme Oxygenase-1 / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000378:metabolism / Q000627:therapeutic use
D006418:Heme; D002248:Carbon Monoxide; D007501:Iron; D051547:Heme Oxygenase-1; D001664:Biliverdine