Markers of extracellular matrix remodeling and systemic inflammation in patients with heritable thoracic aortic diseases

Multidimensional excavation of the current status and trends of mechanobiology in cardiovascular homeostasis and remodeling within 20 years

Mechanobiology is essential for cardiovascular structure and function and regulates the normal physiological and pathological processes of the cardiovascular system. Cells in the cardiovascular system are extremely sensitive to their mechanical environment, and once mechanical stimulation is abnormal, the homeostasis mechanism is damaged or lost, leading to the occurrence of pathological remodeling diseases. In the past 20 years, many articles concerning the mechanobiology of cardiovascular homeostasis and remodeling have been published. To better understand the current development status, research hotspots and future development trends in the field, this paper uses CiteSpace software for bibliometric analysis, quantifies and visualizes the articles published in this field in the past 20 years, and reviews the research hotspots and emerging trends. The regulatory effects of mechanical stimulation on the biological behavior of endothelial cells, smooth muscle cells and the extracellular matrix, as well as the mechanical-related remodeling mechanism in heart failure, have always been research hotspots in this field. This paper reviews the research advances of these research hotspots in detail. This paper also introduces the research status of emerging hotspots, such as those related to cardiac fibrosis, homeostasis, mechanosensitive transcription factors and mechanosensitive ion channels. We hope to provide a systematic framework and new ideas for follow-up research on mechanobiology in the field of cardiovascular homeostasis and remodeling and promote the discovery of more therapeutic targets and novel markers of mechanobiology in the cardiovascular system.

Analysis of FBN1, TGFβ2, TGFβR1 and TGFβR2 mRNA as Key Molecular Mechanisms in the Damage of Aortic Aneurysm and Dissection in Marfan Syndrome

Marfan syndrome (MFS) is an inherited connective tissue disorder, with aortic root aneurysm and/or dissection being the most severe and life-threatening complication. These conditions have been linked to pathogenic variants in the FBN1 gene and dysregulated TGFβ signaling. Our objective was to evaluate the mRNA expression of FBN1, TGFBR1, TGFBR2, and TGFB2 in aortic tissue from MFS patients undergoing surgery for aortic dilation. This prospective study (2014-2023) included 20 MFS patients diagnosed according to the 2010 Ghent criteria, who underwent surgery for aneurysm or dissection based on Heart Team recommendations, along with 20 non-MFS controls. RNA was extracted, and mRNA levels were quantified using RT-qPCR. Patients with dissection showed significantly higher FBN1 mRNA levels [79 (48.1-110.1)] compared to controls [37.2 (25.1-79)] (p = 0.03). Conversely, TGFB2 expression was significantly lower in MFS patients [12.17 (6.54-24.70)] than in controls [44.29 (25.85-85.36)] (p = 0.029). A positive correlation was observed between higher FBN1 expression and a larger sinotubular junction diameter (r = 0.42, p = 0.07), while increased FBN1 expression was particularly evident in MFS patients with dissection. Additionally, TGFB2 expression showed an inverse correlation with ascending aortic diameter (r = 0.53, p = 0.01). In aortic tissue, we found decreased TGFB2 and receptor levels alongside increased FBN1 mRNA levels. These molecular alterations may reflect compensatory mechanisms in response to tissue damage caused by mechanical stress, leading to dysregulation of physiological signaling pathways and ultimately contributing to aortic dilation in MFS.

Establishment of a nomogram model based on immune-related genes using machine learning for aortic dissection diagnosis and immunomodulation assessment

The clinical manifestation of aortic dissection (AD) is complex and varied, making early diagnosis crucial for patient survival. This study aimed to identify immune-related markers to establish a nomogram model for AD diagnosis. Three datasets from GEO-GSE52093, GSE147026 and GSE153434-were combined and used for identification of immune-related causative genes using weighted gene co-expression network analysis, and 136 immune-related genes were obtained. Then, 15 pivotal genes were screened by the protein-protein interaction network. Through machine learning including the Least Absolute Shrinkage and Selection Operator algorithm, random forest algorithm, and multivariate logistic regression, four key feature genes were obtained-CXCL1, ITGA5, PTX3, and TIMP1-and the diagnostic scores based on these four genes were proved to be effective in distinguishing between AD patients and healthy donors. External dataset (GSE98770 and GSE190635) validation revealed this nomogram displayed strong predictive significance. Further analysis revealed that these genes are related with neutrophils, resting NK cells, resting mast cells, activated mast cells, activated dendritic cells, central memory CD4 T cells, γδ T cells, natural killer T cells, and myeloid-derived suppressor cells in AD. Finally, these four genes were validated to be upregulated in AD patients' tissue and serum samples compared with controls. These results suggest that this nomogram model, using machine learning identified four immune-related genes CXCL1, ITGA5, PTX3, and TIMP1, displays superior diagnostic ability in distinguishing AD and healthy individuals, and immune cells commonly associated with these hub genes may be therapeutic targets for AD.

FABP5+ macrophages contribute to lipid metabolism dysregulation in type A aortic dissection

Type A aortic dissection (TAAD) is an acute onset disease with a high mortality rate. TAAD is caused by a tear in the aortic intima and subsequent blood infiltration. The most prominent characteristics of TAAD are aortic media degeneration and inflammatory cell infiltration, which disturb the structural integrity and function of nonimmune and immune cells in the aortic wall. However, to date, there is no systematic evaluation of the interactions between nonimmune cells and immune cells and their effects on metabolism in the context of aortic dissection. Here, multiomics, including bulk RNA-seq, single-cell RNA-seq, and lipid metabolomics, was applied to elucidate the comprehensive TAAD lipid metabolism landscape. Normally, monocytes in the stress response state secrete a variety of cytokines. Injured fibroblasts lack the ability to degrade lipids, which is suspected to contribute to a high lipid environment. Macrophages differentiate into fatty acid binding protein 5-positive (FABP5+) macrophages under the stimulation of metabolic substrates. Moreover, the upregulation of Fabp5+ macrophages were retrospectively validated in TAAD model mice and TAAD patients. Finally, Fabp5+ macrophages can generate a wide range of proinflammatory cytokines, which possibly contribute to TAAD pathogenesis.

Olfactory Receptors and Aortic Aneurysm: Review of Disease Pathways

Aortic aneurysm, the pathological dilatation of the aorta at distinct locations, can be attributed to many different genetic and environmental factors. The resulting pathobiological disturbances generate a complex interplay of processes affecting cells and extracellular molecules of the tunica interna, media and externa. In short, aortic aneurysm can affect processes involving the extracellular matrix, lipid trafficking/atherosclerosis, vascular smooth muscle cells, inflammation, platelets and intraluminal thrombus formation, as well as various endothelial functions. Many of these processes are interconnected, potentiating one another. Newer discoveries, including the involvement of odorant olfactory receptors in these processes, have further shed light on disease initiation and pathology. Olfactory receptors are a varied group of G protein coupled-receptors responsible for the recognition of chemosensory information. Although they comprise many different subgroups, some of which are not well-characterized or identified in humans, odorant olfactory receptors, in particular, are most commonly associated with recognition of olfactory information. They can also be ectopically localized and thus carry out additional functions relevant to the tissue in which they are identified. It is thus the purpose of this narrative review to summarize and present pathobiological processes relevant to the initiation and propagation of aortic aneurysm, while also incorporating evidence associating these ectopically functioning odorant olfactory receptors with the overall pathology.

Aortic aneurysm: pathophysiology and therapeutic options

Aortic aneurysm (AA) is an aortic disease with a high mortality rate, and other than surgery no effective preventive or therapeutic treatment have been developed. The renin-angiotensin system (RAS) is an important endocrine system that regulates vascular health. The ACE2/Ang-(1-7)/MasR axis can antagonize the adverse effects of the activation of the ACE/Ang II/AT1R axis on vascular dysfunction, atherosclerosis, and the development of aneurysms, thus providing an important therapeutic target for the prevention and treatment of AA. However, products targeting the Ang-(1-7)/MasR pathway still lack clinical validation. This review will outline the epidemiology of AA, including thoracic, abdominal, and thoracoabdominal AA, as well as current diagnostic and treatment strategies. Due to the highest incidence and most extensive research on abdominal AA (AAA), we will focus on AAA to explain the role of the RAS in its development, the protective function of Ang-(1-7)/MasR, and the mechanisms involved. We will also describe the roles of agonists and antagonists, suggest improvements in engineering and drug delivery, and provide evidence for Ang-(1-7)/MasR's clinical potential, discussing risks and solutions for clinical use. This study will enhance our understanding of AA and offer new possibilities and promising targets for therapeutic intervention.

Molecular Mechanisms Underlying Vascular Remodeling in Hypertension

Hypertension, a common cardiovascular disease, is primarily characterized by vascular remodeling. Recent extensive research has led to significant progress in understanding its mechanisms. Traditionally, vascular remodeling has been described as a unidirectional process in which blood vessels undergo adaptive remodeling or maladaptive remodeling. Adaptive remodeling involves an increase in vessel diameter in response to increased blood flow, while maladaptive remodeling refers to the narrowing or thickening of blood vessels in response to pathological conditions. However, recent research has revealed that vascular remodeling is much more complex. It is now understood that vascular remodeling is a dynamic interplay between various cellular and molecular events. This interplay process involves different cell types, including endothelial cells, smooth muscle cells, and immune cells, as well as their interactions with the extracellular matrix. Through these interactions, blood vessels undergo intricate and dynamic changes in structure and function in response to various stimuli. Moreover, vascular remodeling involves various factors and mechanisms such as the renin-angiotensin-aldosterone system (RAS), oxidative stress, inflammation, the extracellular matrix (ECM), sympathetic nervous system (SNS) and mechanical stress that impact the arterial wall. These factors may lead to vascular and circulatory system diseases and are primary causes of long-term increases in systemic vascular resistance in hypertensive patients. Additionally, the presence of stem cells in adventitia, media, and intima of blood vessels plays a crucial role in vascular remodeling and disease development. In the future, research will focus on examining the underlying mechanisms contributing to hypertensive vascular remodeling to develop potential solutions for hypertension treatment. This review provides us with a fresh perspective on hypertension and vascular remodeling, undoubtedly sparking further research efforts aimed at uncovering more potent treatments and enhanced preventive and control measures for this disease.