EPO-cyclosporine combination therapy reduced brain infarct area in rat after acute ischemic stroke: Role of innate immune-inflammatory response, micro-RNAs and MAPK family signaling pathway

This study tested the hypothesis that erythropoietin (EPO) and cyclosporine (CsA) could effectively reduce brain infarct area (BIA) in rat after acute ischemic stroke (AIS) through regulating inflammation, oxidative stress, MAPK family signaling and microRNA (miR-223/miR-30a/miR-383). Adult male Sprague-Dawley rats (n = 48) were equally divided into group 1 (sham control), group 2 (AIS), group 3 [AIS+EPO (5,000 IU/kg at 0.5/24/48 h, subcutaneous)] and group 4 [AIS+CsA (20.0 mg/kg at 0.5/24/48 h, intra-peritoneal)]. By 72 h, histopathology showed that BIA was largest in group 2 and smallest in group 1, and significantly larger in group 4 than group 3 (all P<0.0001). The three microRNAs expressed were higher in group 2 than in the other three groups (all P<0.04); between these three latter groups there were no significant differences. The protein expressions of MAPK family [phosphorylated (p)-ERK1/2, p-p38/p-JNK], inflammatory (iNOS/MMP-9/TNF-α/NF-κB/IL-12/MIP-1α/CD14/CD68/Ly6g), apoptotic (caspase-3/PARP/mitochondrial-Bax), oxidative-stress (NOX-1/NOX-2/oxidized protein) and mitochondrial-damaged (cytosolic cytochrome-C) biomarkers exhibited an identical pattern to BIA findings (all P<0.0001). The cellular expressions of brain edema (AQP4+), inflammation (CD11+/glial-fibrillary-acid protein+), and cellular damage (TUNEL assay/positive Periodic acid-Schiff stain) biomarkers exhibited an identical pattern, whereas the cellular-integrity markers (neuN+/MAP2+/doublecorin+) exhibited an opposite pattern to BIA (all P value <0.001). EPO-CsA therapy markedly reduced BIA mainly by suppressing the innate immune response to inflammation, oxidative stress, microRNAs (miR-223/miR-30a/miR-383) and MAPK family signaling.