Rapamycin Induces Heme Oxygenase-1 in Liver but Inhibits Bile Flow Recovery after Ischemia

Alwine Kist, Joris Wakkie, Max Madu, Ruth Versteeg, Judith ten Berge, Andrej Nikolic, Vincent Nieuwenhuijs, R Porte, Robert Padbury, Gregory Barritt

    Research output: Contribution to journalArticlepeer-review

    6 Citations (Scopus)

    Abstract

    Background/Aims: Rapamycin, which is employed in the management of patients undergoing liver surgery, induces the synthesis of heme oxygenase-1 (HO-1) in some non-liver cell types. The aim was to investigate whether rapamycin can induce HO-1 expression in the liver, and to test the effects of rapamycin on liver function in the early phase of ischemia reperfusion (IR) injury. Methods: Isolated rat hepatocytes and a rat model of segmental hepatic ischemia and reperfusion were employed. Bile flow was measured gravimetrically or by using indocyanine green. mRNA and protein (by quantitative PCR and Western blot, respectively) and blood concentrations of rapamycin, bilirubin, and liver marker enzymes were measured. Results: In isolated hepatocytes, rapamycin induced a 6-fold increase in HO-1, comparable to that induced by cobalt proporphyrin (CoPP), and a 2-fold increase in peroxiredoxin-1. Pretreatment of rats with rapamycin resulted in a small increase in liver HO-1 expression, a 20% inhibition of the basal rate of bile flow, and a 50% inhibition in the rate of bile flow recovery after ischemia. CoPP increased basal bile flow by 20% and inhibited bile flow recovery by 50%. These effects were associated with small increases in the blood concentrations of bilirubin and liver marker enzymes. Conclusions: Rapamycin, through HO-1 induction, has the potential to protect the liver against damage in the late phase of IR. The inhibition by rapamycin of bile flow indicates that its actions on liver function in the acute phase of IR injury are complex.

    Original languageEnglish
    Pages (from-to)468-475
    Number of pages8
    JournalJournal of Surgical Research
    Volume176
    Issue number2
    DOIs
    Publication statusPublished - Aug 2012

    Keywords

    • bile flow
    • heme oxygenase-1
    • ischemia reperfusion injury
    • isolated hepatocytes
    • liver
    • quantitative PCR
    • rapamycin
    • rat

    Fingerprint Dive into the research topics of 'Rapamycin Induces Heme Oxygenase-1 in Liver but Inhibits Bile Flow Recovery after Ischemia'. Together they form a unique fingerprint.

    Cite this