ALDH2 knockout protects against aortic dissection

Abstract

Abstract Background The incidence and mortality of aortic dissection (AD) are increasing. In pathological studies, macrophages, T lymphocytes and dendritic cells were found in the tunica media of the aorta. Acetaldehyde dehydrogenase 2 (ALDH2) gene polymorphisms are associated with a high incidence of hypertension in Asian populations. However, there is no clear evidence of the relationship between ALDH2 and aortic dissection in Asians. The aim of this study was to investigate the incidence of aortic dissection in different ALDH2 genotypes and explore changes in the vasculature. Materials and methods Three-week-old male mice were administered freshly prepared β-aminopropionitrile solution dissolved in drinking water (1 g/kg/d) for 28 days to induce TAD. An animal ultrasound imaging system was used to observe the formation of arterial dissection and changes in cardiac function. Subsequently, mice were euthanized by cervical dislocation. The aortas were fixed for HE staining and EVG staining to observe aortic elastic fiber tears and pseudoluma formation under a microscope. Results Knockout of ALDH2 mitigated β-aminopropionitrile-induced TAD formation in animal studies. Ultrasound results showed that ALDH2 knockout reduced the degree of ascending aortic widening and the incidence of aortic dissection rupture. Pathological sections of multiple aortic segments showed that the protective effect of ALDH2 knockout was observed in not only the ascending aorta but also the aortic arch and descending aorta. The expression levels of genes related to NK CD56bright cells, Th17 cells, T cells and T helper cells were decreased in ALDH2 knockout mice treated with β-aminopropionitrile for 28 days. Conclusion ALDH2 knockout protects against aortic dissection by altering the inflammatory response and immune response and protecting elastic fibers.

Keywords

• Aorta dissection
• ALDH2 knockout
• β-aminopropionitrile