B cell subsets contribute to myocardial protection by inducing neutrophil apoptosis after ischemia and reperfusion

The immune system in cardiovascular diseases: from basic mechanisms to therapeutic implications

Immune system plays a crucial role in the physiological and pathological regulation of the cardiovascular system. The exploration history and milestones of immune system in cardiovascular diseases (CVDs) have evolved from the initial discovery of chronic inflammation in atherosclerosis to large-scale clinical studies confirming the importance of anti-inflammatory therapy in treating CVDs. This progress has been facilitated by advancements in various technological approaches, including multi-omics analysis (single-cell sequencing, spatial transcriptome et al.) and significant improvements in immunotherapy techniques such as chimeric antigen receptor (CAR)-T cell therapy. Both innate and adaptive immunity holds a pivotal role in CVDs, involving Toll-like receptor (TLR) signaling pathway, nucleotide-binding oligomerization domain-containing proteins 1 and 2 (NOD1/2) signaling pathway, inflammasome signaling pathway, RNA and DNA sensing signaling pathway, as well as antibody-mediated and complement-dependent systems. Meanwhile, immune responses are simultaneously regulated by multi-level regulations in CVDs, including epigenetics (DNA, RNA, protein) and other key signaling pathways in CVDs, interactions among immune cells, and interactions between immune and cardiac or vascular cells. Remarkably, based on the progress in basic research on immune responses in the cardiovascular system, significant advancements have also been made in pre-clinical and clinical studies of immunotherapy. This review provides an overview of the role of immune system in the cardiovascular system, providing in-depth insights into the physiological and pathological regulation of immune responses in various CVDs, highlighting the impact of multi-level regulation of immune responses in CVDs. Finally, we also discuss pre-clinical and clinical strategies targeting the immune system and translational implications in CVDs.

Anti-inflammatory phenotypes of immune cells after myocardial infarction and prospects of therapeutic strategy

Often causing negative cardiac remodeling and heart failure, a major threat to human life and health, myocardial infarction (MI) is a cardiovascular disease with a high morbidity and fatality rate worldwide. Maintaining ordinary heart function depends significantly on the immune system. Necrotic cardiomyocyte signals promote specific immunity and activate general immunity as the disease progresses in MI. Complex immune cells play a key role in all stages of MI progression by removing necrotic cardiomyocytes and tissue and promoting the healing of damaged tissue cells. Immune cells can help to regrow injured heart muscle as well as enable both inflammation and cardiomyocyte death. Immune cells are essential elements that help the immune system carry out its protective function. There are two types of immunity: nonspecific immunity and specific immunity. Developed throughout the long-term evolution of species, nonspecific immunity (including macrophages, myeloid-derived suppressor cells MDSC, natural killer cells NK, neutrophils, and dendritic cells DC) offers immediate and conservative host defense that might destroy healthy tissues because of its nonspecific nature. Precisely acquired immunity, specific immunity helps humoral and cellular immunity mediated through B and T cells correspondingly. These findings offer crucial information needed for the creation of effective immunomodulatory treatment, as discussed in this article.

CT-Based radiomics nomogram of lung and mediastinal features to identify cardiovascular disease in chronic obstructive pulmonary disease: a multicenter study

RATIONALE AND OBJECTIVES

To investigate the performance of two diagnostic models based on CT-derived lung and mediastinum radiomics nomograms for identifying cardiovascular disease (CVD) in Chronic Obstructive Pulmonary Disease (COPD) patients.

MATERIALS AND METHODS

Hospitalized participants with COPD were retrospectively recruited between September 2015 and April 2023. Clinical data and visual coronary artery calcium score (CACS) were collected. Radiomics features of lung and mediastinum were extracted. Least absolute shrinkage and selection operator (LASSO) logistic regression was applied for feature selection and radiomic model construction. We constructed 3 radiomics models, based on lung, mediastinum, and combined lung-and-mediastinum. Multivariate logistic regression model was used to establish radiomics nomograms. The performance of radiomics nomograms was evaluated by area under the ROC curve (AUC) and decision curve analysis (DCA).

RESULTS

Of 686 COPD patients, 131 had a history of CVD. Age, neutrophilic granulocyte percentage, hematocrit and GOLD stage were independent clinical factors for CVD. 12 lung, and 6 mediastinum radiomic features were collected to construct the radiomics models. As the lung-and-mediastinum radiomics model included the same 6 features as the mediastinum model, finally 2 radiomics models were studied (lung, mediastinum). The 2 radiomics nomograms showed better discriminatory ability (AUC: 0.79, 95%CI [0.72, 0.86] for lung; 0.86, 95%CI [0.81, 0.92]) for mediastinum) than the clinical factors model (AUC: 0.71, 95%CI [0.64, 0.78]) and visual CACS (AUC: 0.65, 95%CI [0.57, 0.72]). DCA demonstrated the 2 radiomics nomograms outperformed the clinical factors and CACS across the majority of the range of reasonable threshold probabilities.

CONCLUSION

We developed chest CT-based nomograms to identify CVD in COPD patients, in particular based on mediastinum features, had better discriminatory power than clinical factors and visual CACS.

TRIAL REGISTRATION

This retrospective study was approved by the institutional review boards at Second Affiliated Hospital of Naval Medical University, Tongji Hospital of Tongji University and Sir Run Run Shaw Hospital (ChiCTR2300069929 March 29, 2023). Retrospectively registered.

The effect of TIM1+ Breg cells in liver ischemia-reperfusion injury

Liver transplantation is the only effective method for end-stage liver disease; however, liver ischemia reperfusion injury (IRI) seriously affects donor liver function after liver transplantation. IRI is a pathophysiological process in which organ damage is aggravated after the blood flow and oxygen supply of ischemic organ tissues are restored. It combines the two stages of hypoxic cell stress triggered by ischemia and inflammation-mediated reperfusion injury. Herein, we studied the protective effect and mechanism of the anti-T cell Ig and mucin domain (TIM1) monoclonal antibody, RMT1-10, on hepatic cell injury induced by IRI. First, a liver IRI model was established in vivo. HE, TEM, and Tunel were used to detect liver tissue injury, changes in the liver ultrastructure and liver cell apoptosis, respectively. ELISA were performed to determine the levels of ALT, AST, MDA, GSH, and related inflammatory factors. We found that RMT1-10 could significantly reduce liver injury. Flow cytometry results showed that the number of TIM1+ regulatory B cells (Bregs) in the IRI liver increased briefly, while pretreatment with RMT1-10 could increase the number of TIM1+ Bregs and interleukin-10 (IL-10) secretion in liver IRI model mice, thus playing a protective role in liver reperfusion. When Anti-CD20 was used to remove B cells, RMT1-10 had a reduced effect on liver IRI. Previous data showed that the number of T helper 1 cells (Th1:CD4+; CD8+) increased significantly after IRI. RMT1-10 inhibited Th1 cells; however, it significantly activated regulatory T cells. Sequencing analysis showed that RMT1-10 could significantly downregulate the expression of nuclear factor-kappa B (NF-κB) pathway-related genes induced by IRI. These results suggested that RMT1-10 could promote the maturation of B cells through an atypical NF-κB pathway, thereby increasing the number of TIM1+ Bregs and associated IL-10 secretion to regulate the inflammatory response, thereby protecting against liver IRI.

A Novel Disulfidptosis-Related Diagnostic Gene Signature and Differential Expression Validation in Ischaemic Cardiomyopathy

Ischaemic cardiomyopathy (IC) predominantly arises from prolonged deprivation of oxygen in the coronary arteries, resulting in compromised cardiac contractility or relaxation. This study investigates the role of disulfidptosis-associated genes (DiGs) in IC. Through the analysis of datasets GSE5406 and GSE57338, we explored the association between DiGs and immune characteristics to identify crucial genes contributing to IC development. The support vector machine model emerged as the most effective, identifying key genes such as MYH9, NUBPL, MYL6, MYH10 and NCKAP1. Validation with independent datasets GSE57345, GSE48166 and single-cell GSE145154 further supported these findings, demonstrating high predictive accuracy. Experimental validation in an IC mouse model, using Western blot, immunohistochemistry and RT-qPCR, confirmed the altered expression of these core genes in myocardial ischaemic regions. This research not only elucidates the significance of DiGs in IC but also underscores the diagnostic potential of identified core genes.

B cells in non-lymphoid tissues

B cells have long been understood to be drivers of both humoral and cellular immunity. Recent advances underscore this importance but also indicate that in infection, inflammatory disease and cancer, B cells function directly at sites of inflammation and form tissue-resident memory populations. The spatial organization and cellular niches of tissue B cells have profound effects on their function and on disease outcome, as well as on patient response to therapy. Here we review the role of B cells in peripheral tissues in homeostasis and disease, and discuss the newly identified cellular and molecular signals that are involved in regulating their activity. We integrate emerging data from multi-omic human studies with experimental models to propose a framework for B cell function in tissue inflammation and homeostasis.

Lymphocyte Subset Imbalance in Cardiometabolic Diseases: Are T Cells the Missing Link?

Cardiometabolic and cardiovascular diseases (CVDs) remain the leading cause of death worldwide, with well-established risk factors such as smoking, obesity, and diabetes contributing to plaque formation and chronic inflammation. However, emerging evidence suggests that the immune system plays a more significant role in the development and progression of CVD than previously thought. Specifically, the finely tuned regulation of lymphocyte subsets governs post-injury inflammation and tissue damage resolution and orchestrates the functions and activation of endothelial cells, cardiomyocytes, and fibroblasts in CVD-associated lesions (e.g., atherosclerotic plaques). A deeper understanding of the immune system's involvement in CVD development and progression will provide new insights into disease biology and uncover novel therapeutic targets aimed at re-establishing immune homeostasis. In this review, we summarize the current state of knowledge on the distribution and involvement of lymphocyte subsets in CVD, including atherosclerosis, diabetes, hypertension, myocardial infarction, and stroke.

Stachyose ameliorates myocardial ischemia-reperfusion injury by inhibiting cardiomyocyte ferroptosis and macrophage pyroptosis

Myocardial ischemia-reperfusion injury (MIRI) is a complex pathological process that results from the restoration of blood flow to ischemic myocardium, leading to a series of detrimental effects including oxidative stress and inflammation. Stachyose, a naturally occurring oligosaccharide found in traditional Chinese medicinal herbs, has been suggested to possess therapeutic properties against various pathological conditions. However, its impact on MIRI and the underlying mechanisms have not been fully elucidated. In this study, we aimed to investigate the therapeutic effects of stachyose on MIRI and to uncover the molecular mechanisms involved. Using both in vivo and in vitro models of MIRI, we evaluated the effects of stachyose on cardiac function and cell death pathways. Our results indicate that stachyose significantly improves cardiac function and reduces infarct size in MIRI mice. Mechanistically, stachyose modulates the ferroptotic pathway in cardiomyocytes by upregulating the expression of glutathione peroxidase 4 (GPX4) and reducing lipid peroxides and iron levels. Additionally, stachyose inhibits the pyroptotic pathway in macrophages by downregulating the expression of NLRP3, gasdermin D (GSMD-N), and cleaved-caspase-1, leading to decreased levels of proinflammatory cytokines interleukin (IL)-1β and IL-18. This study demonstrates that stachyose exerts a protective effect against MIRI by targeting both ferroptosis and pyroptosis pathways, suggesting its potential as a novel therapeutic agent for the treatment of MIRI. Further research is warranted to explore the detailed mechanisms and therapeutic potential of stachyose in clinical settings.

Targeting the adaptive immune continuum in atherosclerosis and post-MI injury

Atherosclerotic disease is a cholesterol-rich lipoprotein particle-driven disease resulting in the formation of atherosclerotic plaques in large and medium size arteries. Rupture or erosion of atherosclerotic plaques can trigger the formation of a thrombus causing the obstruction of the blood flow in the coronary artery and thereby leading to myocardial infarction (MI). Inflammation is a crucial pillar of the mechanisms leading to atherosclerosis and governing the cardiac repair post-MI. Dissecting the complex and sophisticated networks of the immune responses underlying the formation of atherosclerotic plaques and affecting the healing of the heart after MI will allow the designing of highly precise immunomodulatory therapies for these settings. Notably, MI also accelerates atherosclerosis via modulating the response of the immune system. Therefore, for the identification of effective and safe therapeutic targets, it is critical to consider the inflammatory continuum that interconnects the two pathologies and identify immunomodulatory strategies that confer a protective effect in both settings or at least, affect each pathology independently. Adaptive immunity, which consists of B and T lymphocytes, is a major regulator of atherosclerosis and post-MI cardiac repair. Here, we review and discuss the effect of potential adaptive immunity-targeting therapies, such as cell-depleting therapies, in atherosclerosis and post-MI cardiac injury.

Therapeutic potential of natural products and underlying targets for the treatment of aortic aneurysm

Aortic aneurysm is a vascular disease characterized by irreversible vasodilatation that can lead to dissection and rupture of the aortic aneurysm, a life-threatening condition. Thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) are two main types. The typical treatments for aortic aneurysms are open surgery and endovascular aortic repair, which are only indicated for more severe patients. Most patients with aneurysms have an insidious onset and slow progression, and there are no effective drugs to treat this stage. The inability of current animal models to perfectly simulate all the pathophysiological states of human aneurysms may be the key to this issue. Therefore, elucidating the molecular mechanisms of this disease, finding new therapeutic targets, and developing effective drugs to inhibit the development of aneurysms are the main issues of current research. Natural products have been applied for thousands of years to treat cardiovascular disease (CVD) in China and other Asian countries. In recent years, natural products have combined multi-omics, computational biology, and integrated pharmacology to accurately analyze drug components and targets. Therefore, the multi-component and multi-target complexity of natural products have made them a potentially ideal treatment for multifactorial diseases such as aortic aneurysms. Natural products have regained popularity worldwide. This review provides an overview of the known natural products for the treatment of TAA and AAA and searches for potential cardiovascular-targeted natural products that may treat TAA and AAA based on various cellular molecular mechanisms associated with aneurysm development.

The roles of Th cells in myocardial infarction

Myocardial infarction, commonly known as a heart attack, is a serious condition caused by the abrupt stoppage of blood flow to a part of the heart, leading to tissue damage. A significant aspect of this condition is reperfusion injury, which occurs when blood flow is restored but exacerbates the damage. This review first addresses the role of the innate immune system, including neutrophils and macrophages, in the cascade of events leading to myocardial infarction and reperfusion injury. It then shifts focus to the critical involvement of CD4+ T helper cells in these processes. These cells, pivotal in regulating the immune response and tissue recovery, include various subpopulations such as Th1, Th2, Th9, Th17, and Th22, each playing a unique role in the pathophysiology of myocardial infarction and reperfusion injury. These subpopulations contribute to the injury process through diverse mechanisms, with cytokines such as IFN-γ and IL-4 influencing the balance between tissue repair and injury exacerbation. Understanding the interplay between the innate immune system and CD4+ T helper cells, along with their cytokines, is crucial for developing targeted therapies to mitigate myocardial infarction and reperfusion injury, ultimately improving outcomes for cardiac patients.