Identification of MicroRNAs with Altered Expression Profiles in a Rat Model of Experimentally Induced Early Cerebral Aneurysms / 대한신경손상학회지

ABSTRACT

OBJECTIVE: Structural adaptation of the vascular wall may occur due to various factors, such as shear stress, pressure, injury or inflammation. The role of microRNAs (miRNAs) in the development of vascular remodeling has been investigated in several studies. Recently, the authors reported altered expression profiles of miRNAs in late stage of experimentally induced giant cerebral aneurysm (CA) in rat models. But, early biologic roles of miRNAs in CA formation have not been explained yet. We employed microarrays analysis to identify miRNA expression profiles in early stage of CA in rat model and to compare with those in late stage of giant CA. METHODS: Seventy, 7-week-old male Sprague-Dawley rats underwent a CA induction procedure. The control animals (n=11) were fed a regular diet, and the experimental animals (n=59) were fed a regular diet with 1% normal saline for two months. Then, the rats were killed, their cerebral arteries were dissected, and the 13 regions of early aneurysmal change on the right olfactory artery-anterior cerebral artery bifurcation were cut for miRNA microarrays analysis. Six miRNAs (miRNA-1, miRNA-448, miRNA-352, miRNA-551b, miRNA-431, and miRNA-485) were randomly chosen for validation using real-time quantitative polymerase chain reaction. RESULTS: Among a set of differentially expressed miRNAs, 15 miRNAs were up-regulated more than 200% and five miRNAs were down-regulated less than 50% in the early CA tissues. CONCLUSIONS: This study provides an overall view of miRNA expression profiles in experimentally induced early CAs and strongly supports the idea that some miRNAs, such as miR-31 and miR-27a, play an important role in pathological processes in early CA formation. Further investigations to detect their exact roles of these miRNAs in the pathogenesis of CA are needed.