Connexin 32 deficiency protects the liver against ischemia/reperfusion injury

Eur J Pharmacol. 2020 Jun 5:876:173056. doi: 10.1016/j.ejphar.2020.173056. Epub 2020 Mar 5.

Abstract

Hepatic ischemia/reperfusion (I/R) injury is a common complication in the clinical setting. Our previous study has shown that connexin 32 (Cx32) plays a major role in renal I/R injury; however, the role of Cx32 in hepatic I/R injury remains unknown. Liver tissue and serum samples from patients undergoing orthotopic liver transplantation (OLT) were used to evaluate the function of Cx32 in OLT post-reperfusion injury. Then, partial hepatic ischemia was established in global Cx32 knockout mice and wild-type mice followed by reperfusion. Hepatic injury markers were examined. Cx32 small interfering RNA and the p53 inhibitor, pifithrin-α, tenovin-1 were used to examine the relationship between Cx32 and the p53/puma pathways in the BRL-3A and murine primary hepatocytes hypoxia/reoxygenation (H/R) model. Corresponding to liver damage, Cx32 was significantly induced both during OLT in human patients and partial hepatic I/R in mice. Cx32 KO mice exhibited less liver injury than controls. Cx32 deficiency significantly suppressed the p53/puma pathways and hepatocyte apoptosis. Similar results were observed in the BRL-3A and murine primary hepatocytes H/R model. Propofol protected against OLT post-reperfusion injury and hepatocyte apoptosis by inhibiting Cx32. In conclusion Cx32 is a novel regulator of hepatic I/R injury through the modulation of hepatocyte apoptosis and damage, largely via the p53/puma signaling pathway.

Keywords: Apoptosis; Connexin 32; Hepatic ischemia/reperfusion injury; Propofol; p53/puma.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Apoptosis Regulatory Proteins / metabolism
  • Connexins / antagonists & inhibitors*
  • Connexins / deficiency
  • Connexins / genetics
  • Disease Models, Animal
  • Gap Junction beta-1 Protein
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism
  • Hepatocytes / pathology
  • Humans
  • Ischemia / metabolism
  • Ischemia / pathology
  • Ischemia / prevention & control*
  • Ischemic Postconditioning
  • Liver / blood supply*
  • Liver / metabolism
  • Liver / pathology
  • Liver Function Tests
  • Liver Transplantation*
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Propofol / administration & dosage
  • Propofol / pharmacology*
  • Prospective Studies
  • Rats
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / pathology
  • Reperfusion Injury / prevention & control*
  • Signal Transduction
  • Tumor Suppressor Protein p53 / metabolism
  • Tumor Suppressor Proteins / metabolism

Substances

  • Apoptosis Regulatory Proteins
  • Connexins
  • PUMA protein, mouse
  • Trp53 protein, mouse
  • Tumor Suppressor Protein p53
  • Tumor Suppressor Proteins
  • Propofol