Moderate aerobic exercise prevents matrix degradation and death in a mouse model of aortic dissection and aneurysm

β-aminopropionitrile-induced thoracic aortopathy is refractory to cilostazol and sildenafil in mice

Thoracic aortopathies are life-threatening diseases including aneurysm, dissection, and rupture. Phosphodiesterases (PDEs) regulate intracellular cyclic nucleotide concentrations. Recent studies report the influences of cilostazol, a PDE3 inhibitor, and sildenafil, a PDE5 inhibitor, on abdominal aortic aneurysm formation. However, their impacts on thoracic aortopathy remain unknown. In this study, we investigated whether cilostazol and sildenafil affect thoracic aortopathy induced by β-aminopropionitrile (BAPN) administration in mice. Bulk RNA sequencing analysis revealed that BAPN administration upregulated Pde3a transcription in the ascending aorta and Pde5a in both ascending and descending regions before thoracic aortopathy formation. Next, we tested the effects of cilostazol or sildenafil on BAPN-induced thoracic aortopathy. BAPN-administered mice were fed a diet supplemented with either cilostazol or sildenafil. Mass spectrometry measurements determined the presence of cilostazol or sildenafil in the plasma of mice fed drug-supplemented diets. However, neither drug altered BAPN-induced aortic rupture nor aneurysm formation and progression. These results provide evidence that cilostazol and sildenafil did not influence BAPN-induced thoracic aortopathy in mice.

Hypertension self-management trajectory patterns and associated factors among Chinese patients with aortic dissection after surgical repair: a longitudinal study

AIMS

In patients with aortic dissection (AD) after surgical repair, especially those with hypertension, better management of blood pressure is associated with better health outcomes. The aim of this study is to identify hypertension self-management trajectory patterns and associated factors among Chinese aortic dissection patients after surgical repair to assist in developing tailored behavioural interventions for this population.

METHODS AND RESULTS

178 patients with aortic dissection who underwent surgical repair were followed for 3 months. Data on hypertension self-management, hypertension knowledge, self-efficacy, and social support were collected before discharge and at 1 and 3 months after discharge. Sociodemographic and clinical data were also collected. A latent class growth model and generalized estimating equations were used to explore hypertension self-management trajectory patterns and factors associated with each pattern. The participants' average age was 57.95 (± 11.27) years. Two hypertension self-management trajectory patterns were identified: 'rapid ascent then suppressed growth' (93.4%) and 'continuously slow ascent' (6.6%). For the 'rapid ascent then suppressed growth' pattern, age, educational background, type of health insurance, family monthly income, self-efficacy, and social support were associated with this pattern (P < 0.05).

CONCLUSION

Healthcare providers may prioritize hypertension self-management for patients who are younger, have lower educational levels, have resident or employee medical insurance and have a family monthly income between 5001 and 10 000 yuan. Self-efficacy and social support might serve as targets for future intervention to improve hypertension self-management.

REGISTRATION

ChiCTR2100050542.

Mitochondrial NAD+ deficiency in vascular smooth muscle impairs collagen III turnover to trigger thoracic and abdominal aortic aneurysm

Thoracic and abdominal aortic aneurysm poses a substantial mortality risk in adults, yet many of its underlying factors remain unidentified. Here, we identify mitochondrial nicotinamide adenine dinucleotide (NAD)⁺ deficiency as a causal factor for the development of aortic aneurysm. Multiomics analysis of 150 surgical aortic specimens indicated impaired NAD+ salvage and mitochondrial transport in human thoracic aortic aneurysm, with expression of the NAD+ transporter SLC25A51 inversely correlating with disease severity and postoperative progression. Genome-wide gene-based association analysis further linked low SLC25A51 expression to risk of aortic aneurysm and dissection. In mouse models, smooth muscle-specific knockout of Nampt, Nmnat1, Nmnat3, Slc25a51, Nadk2 and Aldh18a1, genes involved in NAD+ salvage and transport, induced aortic aneurysm, with Slc25a51 deletion producing the most severe effects. Using these models, we suggest a mechanism that may explain the disease pathogenesis: the production of type III procollagen during aortic medial matrix turnover imposes a high demand for proline, an essential amino acid component of collagen. Deficiency in the mitochondrial NAD⁺ pool, regulated by NAD⁺ salvage and transport, hinders proline biosynthesis in mitochondria, contributing to thoracic and abdominal aortic aneurysm.

Unraveling Elastic Fiber-Derived Signaling in Arterial Aging and Related Arterial Diseases

Arterial stiffening is a significant risk factor for the development of cardiovascular diseases, including hypertension, atherosclerosis, and arteriopathy. The destruction of elastic fibers, accompanied by vascular inflammatory remodeling, is a key process in the progression of arterial stiffening and related pathologies. In young, healthy arteries, intact elastic fibers create a resilient microenvironment that maintains the quiescence of arterial cells. However, with advancing age, these elastic fibers undergo post-translational modifications, such as oxidation, glycosylation, and calcification, leading to their eventual degeneration. This degeneration results in the release of degraded peptides and the formation of an inflammatory, stiffened niche. Elastic fiber degeneration profoundly impacts the proinflammatory phenotypes and behaviors of various arterial cells, including endothelial cells, smooth muscle cells, macrophages, fibroblasts, and mast cells. Notably, the degraded elastic fibers release elastin-derived peptides (EDPs), which act as potent inflammatory molecules. EDPs activate various arterial cellular processes, including inflammatory secretion, cell migration, proliferation, and calcification, by interacting with the elastin receptor complex (ERC). These elastin-related cellular events are commonly observed with aging and in diseased arteries. These findings suggest that the degeneration of the elastic fiber meshwork is a primary event driving arterial inflammation, stiffening, and adverse remodeling with advancing age. Therefore, preserving elastic fibers and blocking the EDP/ERC signaling pathways may offer promising therapeutic strategies for mitigating age-related arterial remodeling and related arterial diseases.

Comprehensive analysis of gene signatures associated with aging in human aortic dissection

Background

Aortic dissection (AD) is a lethal aortic disease with limited effective therapeutic strategies. Aging increases the risk of AD, yet the underlying mechanisms remain unclear. This study aims to analyze the association of aging-related genes (Args) and AD using bioinformatic analysis. This helps provide novel insights into AD pathogenesis and contributes to developing novel therapeutic strategies.

Methods

mRNA (GSE52093, GSE153434), miRNA (GSE98770) and single-cell RNA-sequencing (scRNA-seq, GSE213740) datasets of AD were downloaded from GEO database. Args were downloaded from Aging Atlas database. Differentially-expressed Args were determined by intersecting Args and differentially-expressed mRNAs of two mRNA datasets. Cytoscape was used to identify hub genes and construct hub gene regulatory networks related to miRNAs. Seurat and clusterProfiler R package were used for investigating expression patterns of hub genes at single-cell level, and functional analysis, respectively. To validate the cellular expression pattern of hub genes, the same analysis was applied to our own scRNA-seq data. Drugs targeting hub Args were determined using the DGIdb database.

Results

HGF, CXCL8, SERPINE1, HIF1A, TIMP1, ESR1 and PLAUR were identified as aging-related hub genes in AD. miR-221-3p was predicted to interact with ESR1. A decreased ESR1 expression in smooth muscle cell subpopulation 4 (SMC4) was observed in AD versus normal aortic tissues, which was validated by sequencing 197,605 aortic cells from 13 AD patients. Additionally, upregulated genes of SMC4 in AD tissues were enriched in the "cellular senescence" pathway. These data indicated that decreased ESR1 might promote SMC4 aging during AD formation. Eleven existing drugs targeting hub genes were identified, including ruxolitinib and filgrastim, which are associated with AD.

Conclusions

By sequencing transcriptomic data, this study revealed aging-related hub genes and regulatory network involved in AD formation. Additionally, this study proposed a noteworthy hypothesis that downregulated ESR1 may exacerbate AD by promoting SMC aging, which requires further investigation.

Manual therapy and exercise effects on inflammatory cytokines: a narrative overview

Background

Matching disease and treatment mechanisms is a goal of the Precision Medicine Initiative. Pro- and anti-inflammatory cytokines (e.g., Tumor Necrosis Factor-alpha, Transforming Growth Factor-beta, and Interleukin-2, 10, and 12) have gained a significant amount of interest in their potential role in persistent pain for musculoskeletal (MSK) conditions. Manual therapy (MT) and exercise are two guideline-recommended approaches for treating MSK conditions. The objective of this narrative overview was to investigate of the effects of MT and exercise on pro- and anti-inflammatory cytokines and determine the factors that lead to variability in results.

Methods

Two reviewers evaluated the direction and variabilities of MT and exercise literature. A red, yellow, and green light scoring system was used to define consistencies.

Results

Consistencies in responses were seen with acute and chronic exercise and both pro- and anti-inflammatory cytokines. Chronic exercise is associated with a consistent shift towards a more anti-inflammatory cytokine profile (Transforming Growth Factor-beta, and Interleukin-2 and 13, whereas acute bouts of intense exercise can transiently increase pro-inflammatory cytokine levels. The influence of MT on cytokines was less commonly studied and yielded more variable results.

Conclusion

Variability in findings is likely related to the subject and their baseline condition or disease, when measurement occurs, and the exercise intensity, duration, and an individual's overall health and fitness.

Roles of pyroptosis and immune infiltration in aortic dissection

Introduction: Aortic dissection (AD) is often fatal, and its pathogenesis involves immune infiltration and pyroptosis, though the molecular pathways connecting these processes remain unclear. This study aimed to investigate the role of immune infiltration and pyroptosis in AD pathogenesis using bioinformatics analysis. Methods: Two Gene Expression Omnibus datasets and a Gene Cards dataset of pyroptosis-related genes (PRGs) were utilized. Immunological infiltration was assessed using CIBERSORT, and AD diagnostic markers were identified through univariate logistic regression and least absolute shrinkage and selection operator regression. Interaction networks were constructed using STRING, and weighted gene correlation network analysis (WGCNA) was employed to identify important modules and essential genes. Single-sample gene set enrichment analysis determined immune infiltration, and Pearson correlation analysis assessed the association of key genes with infiltrating immune cells. Results: Thirty-one PRGs associated with inflammatory response, vascular epidermal growth factor receptor, and Rap1 signaling pathways were identified. WGCNA revealed seven important genes within a critical module. CIBERSORT detected immune cell infiltration, indicating significant changes in immune cell infiltration and pyroptosis genes in AD and their connections. Discussion: Our findings suggest that key PRGs may serve as indicators for AD or high-risk individuals. Understanding the role of pyroptosis and immune cell infiltration in AD pathogenesis may lead to the development of novel molecular-targeted therapies for AD. Conclusion: This study provides insights into the molecular mechanisms underlying AD pathogenesis, highlighting the importance of immune infiltration and pyroptosis. Identification of diagnostic markers and potential therapeutic targets may improve the management of AD and reduce associated morbidity and mortality.

Animal Models, Pathogenesis, and Potential Treatment of Thoracic Aortic Aneurysm

Thoracic aortic aneurysm (TAA) has a prevalence of 0.16-0.34% and an incidence of 7.6 per 100,000 person-years, accounting for 1-2% of all deaths in Western countries. Currently, no effective pharmacological therapies have been identified to slow TAA development and prevent TAA rupture. Large TAAs are treated with open surgical repair and less invasive thoracic endovascular aortic repair, both of which have high perioperative mortality risk. Therefore, there is an urgent medical need to identify the cellular and molecular mechanisms underlying TAA development and rupture to develop new therapies. In this review, we summarize animal TAA models including recent developments in porcine and zebrafish models: porcine models can assess new therapeutic devices or intervention strategies in a large mammal and zebrafish models can employ large-scale small-molecule suppressor screening in microwells. The second part of the review covers current views of TAA pathogenesis, derived from recent studies using these animal models, with a focus on the roles of the transforming growth factor-beta (TGFβ) pathway and the vascular smooth muscle cell (VSMC)-elastin-contractile unit. The last part discusses TAA treatment options as they emerge from recent preclinical studies.

Angiogenesis inhibitor-specific hypertension increases the risk of developing aortic dissection

Aortic dissection is an adverse event of angiogenesis inhibitors; however, the association between the drugs and aortic dissection is unclear. Therefore, we investigated if and how angiogenesis inhibitors increase the onset of aortic dissection using pharmacologically-induced aortic dissection-prone model (LAB) mice, cultured endothelial cells, and real-world databases, which is a novel integrated research approach. Disproportionality analysis was performed and calculated using the reporting odds ratio as a risk signal using a worldwide database of spontaneous adverse events to estimate the risk of adverse events. Angiogenesis inhibitors, but not other hypertension-inducing drugs, showed significant risk signals for aortic aneurysms and dissection. A retrospective cohort analysis using JMDC, a medical receipt database in Japan, showed that the history of atherosclerosis and dyslipidemia, but not hypertension, were significantly associated with the onset of aortic dissection during angiogenesis inhibitor medication administration. For in vivo studies, sunitinib (100 mg/kg/day) was administered to LAB mice. Sunitinib increased systolic blood pressure (182 mmHg vs. 288 mmHg with sunitinib; p＜0.01) and the incidence of aortic dissection (40% vs. 59% with sunitinib; p = 0.34) in mice. In vivo and in vitro studies revealed that sunitinib increased endothelin-1 expression and induced endothelial cell damage evaluated by intracellular- and vascular cell adhesion molecule-1 expressions. The increased risk of developing aortic dissection with angiogenesis inhibitors is associated with the development of drug-specific hypertension via endothelial cell damage and endothelin-1 expression. Our findings are invaluable in establishing safer anticancer therapies and strategies to prevent the development of vascular toxicity in high-risk patients.

Dynamical modeling reveals RNA decay mediates the effect of matrix stiffness on aged muscle stem cell fate

Loss of muscle stem cell (MuSC) self-renewal with aging reflects a combination of influences from the intracellular (e.g., post-transcriptional modifications) and extracellular (e.g., matrix stiffness) environment. Whereas conventional single cell analyses have revealed valuable insights into factors contributing to impaired self-renewal with age, most are limited by static measurements that fail to capture nonlinear dynamics. Using bioengineered matrices mimicking the stiffness of young and old muscle, we showed that while young MuSCs were unaffected by aged matrices, old MuSCs were phenotypically rejuvenated by young matrices. Dynamical modeling of RNA velocity vector fields in silico revealed that soft matrices promoted a self-renewing state in old MuSCs by attenuating RNA decay. Vector field perturbations demonstrated that the effects of matrix stiffness on MuSC self-renewal could be circumvented by fine-tuning the expression of the RNA decay machinery. These results demonstrate that post-transcriptional dynamics dictate the negative effect of aged matrices on MuSC self-renewal.

PM2.5 exposure exacerbates mice thoracic aortic aneurysm and dissection by inducing smooth muscle cell apoptosis via the MAPK pathway

Air pollution is a major public health concern worldwide. Exposure to fine particulate matter (PM2.5) is closely associated with cardiovascular diseases. However, the effect of PM2.5 exposure on thoracic aortic aneurysm and dissection (TAAD) has not been fully elucidated. Diesel exhaust particulate (DEP) is an important component of PM2.5, which causes health effects and is closely related to the incidence of cardiovascular disease. In the current study, we found that DEP exposure increased the incidence of aortic dissection (AD) in β-aminopropionitrile (BAPN)-induced thoracic aortic aneurysm (TAA). In addition, exposure to PM2.5 increased the diameter of the thoracic aorta in mice models. The number of apoptotic cells increased in the aortic wall of PM2.5-treated mice, as did the protein expression level of BAX/Bcl2 and cleaved caspase3/caspase3. Using a rhythmically stretching aortic mechanical simulation model, fluorescent staining indicated that PM2.5 administration could induce mitochondrial dysfunction and increase reactive oxygen species (ROS) levels in human aortic smooth muscle cells (HASMCs). Furthermore, ERK1/2 mitogen-activated protein kinase (MAPK) signaling pathways participated in the apoptosis of HASMCs after PM2.5 exposure. Therefore, we concluded that PM2.5 exposure could exacerbate the progression of TAAD, which could be induced by the increased apoptosis in HASMCs through the ERK1/2 MAPK signaling pathway.

Arterial remodeling: the role of mitochondrial metabolism in vascular smooth muscle cells

Arterial remodeling is a common pathological basis of cardiovascular diseases such as atherosclerosis, vascular restenosis, hypertension, pulmonary hypertension, aortic dissection, and aneurysm. Vascular smooth muscle cells (VSMCs) are not only the main cellular components in the middle layer of the arterial wall but also the main cells involved in arterial remodeling. Dedifferentiated VSMCs lose their contractile properties and are converted to a synthetic, secretory, proliferative, and migratory phenotype, playing key roles in the pathogenesis of arterial remodeling. As mitochondria are the main site of biological oxidation and energy transformation in eukaryotic cells, mitochondrial numbers and function are very important in maintaining the metabolic processes in VSMCs. Mitochondrial dysfunction and oxidative stress are novel triggers of the phenotypic transformation of VSMCs, leading to the onset and development of arterial remodeling. Therefore, pharmacological measures that alleviate mitochondrial dysfunction reverse arterial remodeling by ameliorating VSMCs metabolic dysfunction and phenotypic transformation, providing new options for the treatment of cardiovascular diseases related to arterial remodeling. This review summarizes the relationship between mitochondrial dysfunction and cardiovascular diseases associated with arterial remodeling and then discusses the potential mechanism by which mitochondrial dysfunction participates in pathological arterial remodeling. Furthermore, maintaining or improving mitochondrial function may be a new intervention strategy to prevent the progression of arterial remodeling.

Progress in murine models of ruptured abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is a focal dilation of the aorta that is prevalent in aged populations. The progressive and unpredictable expansion of AAA could result in aneurysmal rupture, which is associated with ~80% mortality. Due to the expanded screening efforts and progress in diagnostic tools, an ever-increasing amount of asymptomatic AAA patients are being identified yet without a cure to stop the rampant aortic expansion. A key barrier that hinders the development of effective AAA treatment is our incomplete understanding of the cellular and molecular basis of its pathogenesis and progression into rupture. Animal models provide invaluable mechanistic insights into AAA pathophysiology. However, there is no single experimental model that completely recapitulate the complex biology behind AAA, and different AAA-inducing methodologies are associated with distinct disease course and rupture rate. In this review article, we summarize the established murine models of ruptured AAA and discuss their respective strengths and utilities.

Sports Participation and Physical Activity in Individuals with Heritable Thoracic Aortic Disease and Aortopathy Conditions

The evaluation and management of athletes with HTAD and aortopathy conditions requires shared decision-making encompassing the underlying condition, family history, aortic diameter, and type and intensity of sports and exercise. Mouse models of thoracic aortic disease show that low-to-moderate-level aerobic exercise can maintain aortic architecture and attenuate pathologic aortic root dilation. Although controlled trials in human are lacking, recreational physical activities performed at a low-to-moderate aerobic pace are generally low risk for most individuals with aortopathy conditions. High-intensity, competitive, and contact sports or physical activities are generally prohibited in individuals with aortopathy conditions.

β-Aminopropionitrile-induced aortic aneurysm and dissection in mice

The mechanistic basis for the formation of aortic aneurysms and dissection needs to be elucidated to facilitate the development of effective medications. β-Aminopropionitrile administration in mice has been used frequently to study the pathologic features and mechanisms of aortic aneurysm and dissection. This mouse model mimics several facets of the pathology of human aortic aneurysms and dissection, although many variables exist in the experimental design and protocols that must be resolved to determine its application to the human disease. In the present brief review, we have introduced the development of this mouse model and provided insights into understanding its pathologic features.