Understanding the Molecular Mechanisms of H2's Regulatory Effect on miR-29s for Brain Protection during Deep Hypothermic Circulatory Arrest

Introduction: Research regarding post-operative brain protection after deep hypothermic circulatory arrest (DHCA) has gained attracted significant attention. We previously demonstrated that hydrogen can significantly reverse DHCA-induced brain damage. Method: In the current research, we have established the DHCA model successfully using a modified four-vessel occlusion method and injected miR-29s compounds into the hippocampal tissue of rats. Result: We were surprised to find hydrogen increased miR-29s expression in the hippocampal tissue of a DHCA rat model. The administration of agomiR-29s counteracted DHCA-induced hippocampal tissue injury, while the antamiR-29s had the opposite effects. Conclusion: Based on the above facts, the brain protection mechanism of hydrogen in DHCAtreated rats may be related to the upregulation of miR-29s, which can exert its beneficial effects by alleviating apoptosis, inflammation, and oxidation.