Endovascular Intervention for Aortic Dissection Is "Ascending"

CCDC80 Protects against Aortic Dissection and Rupture by Maintaining the Contractile Smooth Muscle Cell Phenotype

Aortic dissection (AD) is a life-threatening medical emergency characterized by adverse vascular remodeling. Coiled-coil domain-containing protein 80 (CCDC80) plays an essential role in regulating cardiovascular remodeling. This study aims to define the role of CCDC80 in the formation and development of AD. Significant downregulation of CCDC80 in vascular smooth muscle cell (VSMC) in human and mouse AD is identified. Then, CCDC80 knockout mice (CCDC80-/-) and VSMC-specific CCDC80 knockout mice (CCDC80fl/fl SM22α Cre+) treated with angiotensin II (Ang II) or Ang II combined with β-aminopropionitrile monofumarate (BAPN) frequently develop AD with higher frequency and severity, accompanied by severe elastin fragmentation and collagen deposition. Mechanistically, CCDC80 interacts with JAK2, and CCDC80 deficiency promotes VSMC phenotype switching, proliferation, and migration as well as matrix metalloproteinase production by activating the JAK2/STAT3 signaling pathway. Moreover, the JAK2/STAT3 pathway-specific inhibitor ameliorates adverse vascular remodeling and reduces AD formation in CCDC80-knockout mice by mitigating VSMC phenotype switching. In conclusion, CCDC80 deficiency exacerbates the progression of events leading to AD by activating the JAK2/STAT3 pathway involved in regulating the phenotype switching and function of VSMCs. These findings highlight that CCDC80 is a potential key target for the prevention and treatment of AD.

Downregulation of LILRB4 Promotes Human Aortic Smooth Muscle Cell Contractile Phenotypic Switch and Apoptosis in Aortic Dissection

Aortic dissection (AD) is a severe vascular disease with high rates of mortality and morbidity. However, the underlying molecular mechanisms of AD remain unclear. Differentially expressed genes (DEGs) were screened by bioinformatics methods. Alterations of histopathology and inflammatory factor levels in β-aminopropionitrile (BAPN)-induced AD mouse model were evaluated through Hematoxylin-Eosin (HE) staining and Enzyme-linked immunosorbent assay (ELISA), respectively. Reverse transcription quantitative real-time polymerase chain reaction was performed to detect DEGs expression. Furthermore, the role of LILRB4 in AD was investigated through Cell Counting Kit-8 (CCK-8), wound healing, and flow cytometry. Western blotting was employed to assess the phenotypic switch and extracellular matrix (ECM)-associated protein expressions in platelet-derived growth factor-BB (PDGF-BB)-stimulated in vitro model of AD. In the AD mouse model, distinct dissection formation was observed. TNF-α, IL-1β, IL-8, and IL-6 levels were higher in the AD mouse model than in the controls. Six hub genes were identified, including LILRB4, TIMP1, CCR5, CCL7, MSR1, and CLEC4D, all of which were highly expressed. Further exploration revealed that LILRB4 knockdown inhibited the cell vitality and migration of PDGF-BB-induced HASMCs while promoting apoptosis and G0/G1 phase ratio. More importantly, LILRB4 knockdown promoted the protein expression of α-SMA and SM22α, while decreasing the expression of Co1, MMP2, and CTGF, which suggested that LILRB4 silencing promoted contractile phenotypic transition and ECM stability. LILRB4 knockdown inhibits the progression of AD. Our study provides a new potential target for the clinical treatment of AD.

Aortic Dissection: Spectacular Survival or Nightmare?

We describe the case of a male patient who remarkably survived two severe cardiovascular events: ascending aortic dissection and descending aortic dissection two years later. Later, the third occurrence of aortic dissection, this time involving the abdominal aorta, became an absolute nightmare for the patient, progressively being complicated by periaortic hematoma and severe anemia - events that ultimately led to his death.