A novel miRNA mimic attenuates organ injury after hepatic ischemia/reperfusion

Abstract

INTRODUCTION: Extracellular cold-inducible RNA-binding protein (eCIRP) is a novel mediator of inflammation and tissue injury. It has been shown that miRNA 130b-3p acts as an endogenous inhibitor of eCIRP. Because RNA mimics are unstable after in vivo administration, we have chemically engineered miRNA 130b-3p mimic (named PS-OMe miR130) to improve its stability by protection from nuclease activity. We hypothesize that PS-OMe miR130 reduces eCIRP-mediated injury and inflammation in a murine model of hepatic ischemia/ reperfusion (I/R), a model of sterile inflammation. METHODS:Adult male mice underwent 70% hepatic ischemia for 60 minutes and 24-hour reperfusion. At the start of reperfusion, mice were treated intravenously with vehicle (phosphate-buffered saline) or PS-OMe miR130. Blood and liver tissue were collected after 24 hours for biochemical analysis. Apoptosis in the liver tissue was determined by transferase dUTP nick-end labeling assay. RESULTS:After hepatic I/R, organ injury markers including aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase significantly decreased after PS-OMe miR130 treatment. Furthermore, histological analysis of liver sections demonstrated significantly less injury in PS-OMe miR130 treatment mice versus vehicle mice. In addition, tumor necrosis factor α mRNA, interleukin-1β mRNA, and neutrophil infiltration (myeloperoxidase activity and granulocyte receptor 1 immunohistochemistry) were significantly attenuated after PS-OMe miR130 treatment. Finally, apoptosis significantly decreased in liver tissue after treatment. CONCLUSION:PS-OMe miR130 decreases eCIRP-mediated injury and inflammation in a murine model of hepatic I/R.

Novel Ps-Ome Mirna130b-3p Reduces Inflammation and Injury and Improves Survival After Renal Ischemia-Reperfusion Injury

“…Likewise, the differences in perfusion, drug delivery, and serum and tissue eCIRP concentrations after treatment may have important implications that have not been fully investigated in our study. Although we have not directly measured the specific changes to eCIRP in serum or tissues after treatment with PS-OME miR130, we have previously shown that eCIRP is increased in both serum and tissue after renal IR (20). In conjunction with our findings in the CIRPKO mice (35) and the results of our study showing a significant reduction in inflammation and injury, it can be reasoned that the initial strong binding affinity of the PS-OME miR130 with eCIRP would result in a decrease in eCIRP-mediated inflammatory signaling and thus indirectly reduce eCIRP levels in the treated mice.…”

“…However, given that any miRNA is unstable in vivo because of its susceptibility to degradation by nucleases, miRNA 130b-3p was chemically engineered in an in effort to improve its stability and thereby increase its potential efficacy (41). Recently, this modified miRNA, which we termed PS-OME miR130, has shown to reduce inflammation and tissue injury in mice, which underwent either hepatic I/R or cecal ligation puncture sepsis (19,20). It has been shown that using surface plasmon resonance and three-dimensional computational modeling, PS-OME miR130 retained its binding affinity to eCIRP and that the binding was comparable to that which was observed with the unmodified miRNA 130b-3p (19).…”

“…Immediately after the closure, mice were randomly allocated to be administered intravenously, via retro-orbital injection, of PBS (vehicle) or 12.5 nmol of PS-OME miR130 (treatment) in both the 24-h experiment and the 10-day survival experiment. The dosing was based on previous studies showing an effective reduction in inflammatory markers in both unmodified and modified miRNA 130b-3p mimics in other injury models (11,19,20). Analgesia was provided by delayed subcutaneous injection of buprenorphine (50 μg/kg), and resuscitation was provided by 500 μL bolus of normal saline.…”

“…An miRNA 130b-3p mimic was then synthesized, and its effectiveness in reducing inflammation was experimentally confirmed (11). To improve the in vivo miRNA stability, we have chemically engineered the miRNA 130b-3p mimic and designated as PS-OME miR130 (19,20). The selection of modifications was focused on using well-studied miRNA modification strategies and the presence of significant nuclease protective attributes.…”

“…Given that our compound acts specifically on an extracellular target, the focus is on preventing degradation without impeding its eCIRP specific binding affinity (34). In fact, this modified miRNA was shown to successfully reduce tissue injury and inflammation in rodent models of sepsis and hepatic I/R injury (19,20). Previously, we have shown that renal I/R results in elevated serum and tissue levels of eCIRP and additionally that, in CIRP knockout mice, there is an attenuated inflammation and injury response (35).…”