Introduction

Remote ischemic preconditioning (RIPC) is a strategy inducing resistance against ischemia and reperfusion(IR) injury. But the mechanism and the time window of protection representing RIPC efficacy have not been fully elucidated. The aim of this study is find out protective effect of RIPC in mouse model. And select which metabolites show significant changes.

Methods

Total 30, male, wild-type C57BL/6 mice aged 8-10 weeks were utilized. RIPC was accomplished with clamping of the femoral bundle through a longitudinal incision of the thigh. The RIPC protocol consisted of five minutes ischemia followed by five minutes reperfusion. Kidney ischemia was accomplished with clamping of the left renal pedicle. After 45 minutes of warm ischemia, the de-clamping was done for reperfusion for 24 hrs. Mice were randomly divided into four groups: sham (n=7), IR (n=7), late RIPC+IR (n=8, RIPC, 24 hrs before IR), early RIPC+IR group (n=8, RIPC, 2 hrs before IR). Histologic analysis and multi-omics study was performed; genomics, transcriptomics, proteomics and metabolomics for metabolites.

Results

There was a significant increase in acute tubular injury in IR group compared to sham group. Also, both late and early RIPC showed same protective effects on IR insults significantly. Large-scale metabolome analyses with shows significant changes of endogenous metabolome in RIPC group such as betaine aldehyde, adenosine and sphinganine in kidney tissue and inosine-5-carboxylate in urine and serum. The mRNA microarray showed significantly different expressions in 206 genes between sham and IR groups among the 14,205 genes. After the pathway and network analyses the results showed inflammation relating network was representative in the IR group. And we identified genes participating in this network such as GPX1, CHDH, ADA, PNP and PLA2 and one down-regulated gene of ADK. The integrated metabolic pathway analysis obtained from combined metabolomics and mRNA expression studies. The result showed that late and early RIPC intervention has impact through the pathways that purine metabolism, osmotic regulation and inflammation.

Conclusions

IRI could cause of acute rejection and affect metabolome and transcriptome. It may changes in metabolites, mRNAs and proteins which play important roles in maintaining cell survival and homeostasis such as purine metabolism, osmotic regulation, cell membrane integrity and energy balance.

CITATION INFORMATION: Cho S, Min S.-I, Kim S.-Y, Cho M.-J, Cho W, Ahn S, Min S.-K, Ha J. Deciphering the Mechanism of Remote Ischemic Preconditioning and Its Potential Benefits in Ischemia/Reperfusion Injury by Metabolomics. Am J Transplant. 2017;17 (suppl 3).

« Back to 2017 American Transplant Congress