miR-183-5p alleviates early injury after intracerebral hemorrhage by inhibiting heme oxygenase-1 expression.

Differences in microRNA (miRNA) expression after intracerebral hemorrhage (ICH) have been reported in human and animal models, and miRNAs are being investigated as a new treatment for inflammation and oxidative stress after ICH. In this study, we found that microRNA-183-5p expression was decreased in the mouse brain after ICH. To investigate the effect of miRNA-183-5p on injury and repair of brain tissue after ICH, saline, miRNA-183-5p agomir, or miRNA-183-5p antagomir were injected into the lateral ventricles of 8-week-old mice with collagenase-induced ICH. Three days after ICH, mice treated with exogenous miRNA-183-5p showed less brain edema, neurobehavioral defects, inflammation, oxidative stress, and ferrous deposition than control mice. In addition, by alternately treating mice with a heme oxygenase-1 (HO-1) inducer, a HO-1 inhibitor, a nuclear factor erythroid 2-related factor (Nrf2) activator, and Nrf2 knockout, we demonstrated an indirect, HO-1-dependent regulatory relationship between miRNA-183-5p and Nrf2. Our results indicate that miRNA-183-5p and HO-1 are promising therapeutic targets for controlling inflammation and oxidative damage after hemorrhagic stroke.