Project description:The mechanism by which aging induces aortic aneurysm and dissection (AAD) remains unclear. A total of 430 subjects were recruited for screening of differentially expressed plasma microRNAs. We found that miR-1204 was significantly increased in both plasma and aorta of elder patients with AAD, and was positively correlated with age. Cell senescence induced the expression of miR-1204 through p53 interaction with plasmacytoma variant translocation 1, and miR-1204 induced vascular smooth muscle cell (VSMC) senescence to form a positive feedback loop. miR-1204 aggravated angiotensin II-induced AAD formation, and inhibition of miR-1204 attenuated β-aminopropionitrile monofumarate-induced AAD formation. Mechanistically, miR-1204 directly targeted myosin light chain kinase (MYLK) to promote VSMCs to acquire senescence-associated secretory phenotype (SASP) and lose their contractile phenotype. Overexpression of MYLK reversed miR-1204-induced VSMC senescence, SASP and contractile phenotype changes, and the decrease of transforming growth factor-β signaling pathway. Our findings suggest aging aggravates AAD via 75 miR-1204-MYLK signaling axis.
Project description:The mechanism by which aging induces aortic aneurysm and dissection (AAD) remains unclear. A total of 430 subjects were recruited for screening of differentially expressed plasma microRNAs. We found that miR-1204 was significantly increased in both plasma and aorta of elder patients with AAD, and was positively correlated with age. Cell senescence induced the expression of miR-1204 through p53 interaction with plasmacytoma variant translocation 1, and miR-1204 induced vascular smooth muscle cell (VSMC) senescence to form a positive feedback loop. miR-1204 aggravated angiotensin II-induced AAD formation, and inhibition of miR-1204 attenuated β-aminopropionitrile monofumarate-induced AAD formation. Mechanistically, miR-1204 directly targeted myosin light chain kinase (MYLK) to promote VSMCs to acquire senescence-associated secretory phenotype (SASP) and lose their contractile phenotype. Overexpression of MYLK reversed miR-1204-induced VSMC senescence, SASP and contractile phenotype changes, and the decrease of transforming growth factor-β signaling pathway. Our findings suggest aging aggravates AAD via miR-1204-MYLK signaling axis.
Project description:The mechanism by which aging induces aortic aneurysm and dissection (AAD) remains unclear. We found that miR-1204 was significantly increased in both plasma and aorta of elder patients with AAD, and was positively correlated with age. Cell senescence induced the expression of miR-1204 through p53 interaction with plasmacytoma variant translocation 1, and miR-1204 induced vascular smooth muscle cell (VSMC) senescence to form a positive feedback loop.
Project description:Aneurysmatic and dissection cells show a specific alteration of gene expression, which allow a disease specific distinction. We used microarrays to analyse the cellular gene expression of controls, thoracic aortic aneurysm, and aortic dissection.
Project description:Conducted proteomics on samples from patients with aortic aneurysm and from non-dilated controls. Furthermore, we investigated both patients with bicuspid aortic valves (BAV) and also the more normal tricuspid aortic valves (TAV). The aim was to elucidate the molecular mechanisms behind the higher propensity of BAV patients to develop aorta dilation and consequent aortic aneurysm.
Project description:Although abnormal TGFbeta signaling is observed in several heritable forms of thoracic aortic aneurysms and dissections including Marfan syndrome, the precise role of TGFbeta signaling in aortic disease progression is still disputed. Using a mouse genetic approach and quantitative isobaric labeling proteomics, we sought to investigate the role of TGFbeta signaling in molecular pathways of pathogenesis associated with development of aortic aneurysm and aortic rupture. This study reports an isoform-specific effect of TGFbeta in MFS aortic disease and the effects of deleting the first hybrid domain of fibrillin-1 on TGFbeta signaling. Distinct molecular differences in mouse models of aneurysm (Fbn_GT-8_plus), of aneurysm and rupture (Fbn1_GT-8_H1delta), and of microdissection (Fbn1_H1delta_plus) were identified, which associated with TGFbeta signaling and extracellular matrix composition, possibly contributing to the development of dissection and rupture. These findings offer new insights into the pathophysiological mechanisms that potentially drive initiation of aortic dissection and could pave the way for development of new treatment targets of aortic disease.
Project description:Abdominal aortic aneurysm (AAA) is usually asymptomatic until life-threatening complications occur, predominantly involving aortic rupture. Currently, no drug-based treatments are available, primarily due to limited understanding of AAA pathogenesis. The transcriptional regulator PR domain–containing protein 16 (PRDM16) is highly expressed in the aorta, but its functions in the aorta are largely unknown. By RNA-seq analysis, we found that vascular smooth muscle cell–specific (VSMC-specific) Prdm16-knockout (Prdm16SMKO) mice already showed extensive changes in the expression of genes associated with extracellular matrix (ECM) remodeling and inflammation in the abdominal aorta under normal housing conditions without any pathological stimuli. Human AAA lesions displayed lower PRDM16 expression. Periadventitial elastase application to the suprarenal region of the abdominal aorta aggravated AAA formation in Prdm16SMKO mice. During AAA development, VSMCs undergo apoptosis because of both intrinsic and environmental changes, including inflammation and ECM remodeling. Prdm16 deficiency promoted inflammation and apoptosis in VSMCs. A disintegrin and metalloproteinase 12 (ADAM12) is a gelatinase that can degrade various ECMs. We found that ADAM12 is a target of transcriptional repression by PRDM16. Adam12 knockdown reversed VSMC apoptosis induced by Prdm16 deficiency. Our study demonstrated that PRDM16 deficiency in VSMCs promoted ADAM12 expression and aggravates AAA formation, which may provide potential targets for AAA treatment.