The synergistic mechanism of fibroblast growth factor 18 and integrin β1 in rat abdominal aortic aneurysm repair.

Background: Abdominal aortic aneurysms have a high mortality rate. While surgery is the preferred treatment method, the biological repair of abdominal aortic aneurysms is being increasingly studied. We performed cellular and animal experiments to investigate the simultaneous function and mechanism of fibroblast growth factor 18 and integrin β1 in the biological repair of abdominal aortic aneurysms.

Methods: Endothelial and smooth muscle cells of rat arteries were used for the cellular experiments. Intracellular integrin β1 expression was regulated through lentiviral transfection. Interventions with fibroblast growth factor 18 were determined according to the experimental protocol. Several methods were used to detect the expression of elastic fiber component proteins, cell proliferation, and migratory activity of endothelial and smooth muscle cells after different treatments. For animal experiments, abdominal aortic aneurysms were induced in rats by wrapping the abdominal aortae in sterile cotton balls soaked with CaCl solution. Fibroblast growth factor 18 was administered through tail vein injections. The local expression of integrin β1 was regulated through lentiviral injections into the adventitia of the abdominal aortic aneurysms. The abdominal aortae were harvested for pathological examinations and tensile mechanical tests.

Results: The expression of integrin β1 in endothelial and smooth muscle cells could be regulated effectively through lentiviral transfection. Animal and cellular experiments showed that fibroblast growth factor 18 + integrin β1 could improve the expression of elastic fiber component proteins and enhance the migratory and proliferative activities of smooth muscle and endothelial cells. Moreover, animal experiments showed that fibroblast growth factor 18 + integrin β1 could enhance the aortic integrity to withstand stretch of aortic aneurysm tissue.

Conclusion: Fibroblast growth factor 18 + integrin β1 improved the biological repair of abdominal aortic aneurysms in rats by increasing the expression of elastic proteins, improving the migratory and proliferative abilities of endothelial and smooth muscle cells, and improving aortic remodeling.