Primary Cilia Deficiency Induces Intracranial Aneurysm

Intracranial aneurysm (IA) rupture is life-threatening. However, the mechanisms underlying IA initiation, progression, and rupture remain poorly understood. In the present study, we examined the role of primary cilia in IA development.

IA was experimentally induced in mice with elastase and angiotensin II treatment. The number of cells with primary cilia was determined in both IA and peri-IA regions. The role of primary cilia in IA development was assessed through knocking out or manipulating the expression of important components of primary cilia. Finally the role of primary cilia in human IA patients was studied. In the mice model of IA, the primary cilia number was significantly decreased in the IA region. Knocking out Polycystin 1, Polycystin 2, and Intraflagellar Transport 88 in mice would increase the susceptibility of mice to IA development. The IA development could be modulated through manipulating the pathways that regulate primary cilia dynamics. And chemical screening showed that the three factors (PHA 680623, Rapamycin, and Forskolin) could efficiently suppress the IA development. Finally, we demonstrated that the primary cilia deficiency in IA development is conserved in humans. And IA patients had a higher frequency of gene mutations which are related to primary cilia regulation.

Our study provides an important support for the role of primary cilia in the development of IA. The primary cilia stabilizing chemicals might be useful for preventing IA development.