Erythropoietin pretreatment ameliorates renal ischaemia-reperfusion injury by activating PI3K/Akt signalling

Nephrology (Carlton). 2015 Apr;20(4):266-72. doi: 10.1111/nep.12384.

Abstract

Aim: Renal ischaemia-reperfusion (I/R) injury, a primary cause of acute renal failure, can induce high morbidity and mortality. This study aimed to explore the effect of erythropoietin on renal I/R injury and its underlying mechanism.

Methods: Fifty male Sprague-Dawley rats were randomly allocated to three groups (n = 10): the sham group, the renal ischaemia-reperfusion-saline (IRI) group, and the IRI+-Erythropoietin (EPO) group. Erythropoietin (250, 500, 1000 U/kg) was intraperitoneally injected 30 min before inducing I/R. Renal I/R injury were induced by clamping the left renal artery for 30 min followed by reperfusion, along with a contralateral nephrectomy. Renal function and histological damage were determined after 24 h reperfusion. The expression of pro-inflammatory cytokines interleukin-6 (IL-6), interleukin-1 β (IL-1β), and tumour necrosis factor-α (TNF-α) in the serum and renal tissue were evaluated by enzyme linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Further, the effects of erythropoietin on PI3K/Akt signalling, erythropoietin receptor (EPOR) and nuclear factor (NF)-κB activation were measured by Western blotting.

Results: Erythropoietin pretreatment can significantly decrease the level of renal dysfunction in a dose-dependent manner, attenuated the renal histological changes, the expression of TNF-α, IL-1β, and IL-6, the levels of reactive oxygen species (ROS) production and NF-κB p65 phosphorylation in renal tissue upon IRI. Moreover, erythropoietin pretreatment could further activate the PI3K/Akt signalling and induced EPOR activity.

Conclusions: Erythropoietin pretreatment could attenuate renal I/R injury by suppressing inflammation, which was associated with activating PI3K/Akt signalling though EPOR activation. Our findings suggest that erythropoietin may be a novel practical strategy to prevent renal I/R injury.

Keywords: PI3K/Akt; erythropoietin; renal ischaemia reperfusion injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Kidney Injury / blood
  • Acute Kidney Injury / enzymology
  • Acute Kidney Injury / pathology
  • Acute Kidney Injury / prevention & control*
  • Animals
  • Anti-Inflammatory Agents / administration & dosage*
  • Biomarkers / blood
  • Cytoprotection
  • Disease Models, Animal
  • Enzyme Activation
  • Erythropoietin / administration & dosage*
  • Inflammation Mediators / blood
  • Interleukin-1beta / blood
  • Interleukin-6 / blood
  • Kidney / drug effects*
  • Kidney / enzymology
  • Kidney / pathology
  • Male
  • Phosphatidylinositol 3-Kinase / metabolism*
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Rats, Sprague-Dawley
  • Reactive Oxygen Species / metabolism
  • Receptors, Erythropoietin / agonists
  • Receptors, Erythropoietin / metabolism
  • Reperfusion Injury / blood
  • Reperfusion Injury / enzymology
  • Reperfusion Injury / pathology
  • Reperfusion Injury / prevention & control*
  • Signal Transduction / drug effects*
  • Transcription Factor RelA / metabolism
  • Tumor Necrosis Factor-alpha / blood

Substances

  • Anti-Inflammatory Agents
  • Biomarkers
  • IL1B protein, rat
  • Inflammation Mediators
  • Interleukin-1beta
  • Interleukin-6
  • Reactive Oxygen Species
  • Receptors, Erythropoietin
  • Rela protein, rat
  • Transcription Factor RelA
  • Tumor Necrosis Factor-alpha
  • Erythropoietin
  • Phosphatidylinositol 3-Kinase
  • Proto-Oncogene Proteins c-akt