Matricellular proteins in atherosclerosis development

The role of Epsins in atherosclerosis: From molecular mechanisms to therapeutic applications

Atherosclerosis is a multifaceted disease characterised by chronic inflammation and vascular remodelling, leading to plaque formation and cardiovascular complications. Recent evidence highlights the critical role of epsins, a family of endocytic proteins, in the pathogenesis of atherosclerosis. This manuscript explores the multifarious functions of epsins in atherosclerosis, focusing on their involvement in angiogenesis, lymphangiogenesis, and the modulation of key signalling pathways. We discuss how epsins facilitate EndoMT through their interaction with the TGFβ signalling pathway, which contributes to vascular smooth muscle cell-like phenotypes and plaque instability. Additionally, we examine the therapeutic potential of targeting epsins, elucidating their interactions with crucial partners such as LDLR, LRP-1, and TLR 2/4, among others, in mediating lipid metabolism and inflammation. Furthermore, we highlight the promising prospects of epsin-targeting peptides and small interfering RNAs as therapeutic agents for atherosclerosis treatment. Despite these advancements, the research faces limitations, including a reliance on specific mouse models and a need for comprehensive studies on the long-term effects of epsin modulation. Therefore, future investigations should focus on elucidating the detailed mechanisms of epsin function and their implications in cardiovascular health, fostering collaborations to translate basic research into innovative therapeutic strategies. This work underscores the necessity for further exploration of epsins to unlock their full therapeutic potential in combating atherosclerosis and related cardiovascular diseases.

Unravelling molecular mechanisms in atherosclerosis using cellular models and omics technologies

Despite the discovery and prevalent clinical use of potent lipid-lowering therapies, including statins and PCSK9 inhibitors, cardiovascular diseases (CVD) caused by atherosclerosis remain a large unmet clinical need, accounting for frequent deaths worldwide. The pathogenesis of atherosclerosis is a complex process underlying the presence of modifiable and non-modifiable risk factors affecting several cell types including endothelial cells (ECs), monocytes/macrophages, smooth muscle cells (SMCs) and T cells. Heterogeneous composition of the plaque and its morphology could lead to rupture or erosion causing thrombosis, even a sudden death. To decipher this complexity, various cell model systems have been developed. With recent advances in systems biology approaches and single or multi-omics methods researchers can elucidate specific cell types, molecules and signalling pathways contributing to certain stages of disease progression. Compared with animals, in vitro models are economical, easily adjusted for high-throughput work, offering mechanistic insights. Hereby, we review the latest work performed employing the cellular models of atherosclerosis to generate a variety of omics data. We summarize their outputs and the impact they had in the field. Challenges in the translatability of the omics data obtained from the cell models will be discussed along with future perspectives.

Insoluble proteomics analysis of acute intracranial large vessel occlusive thrombus

BACKGROUND

Acute large vessel occlusion (LVO) stroke is highly prevalent and severe. Despite thrombolytic therapy, many patients experience substantial complications. Understanding the origins, constituents, and pathologic processes involved in thrombus formation in acute intracranial large artery occlusion is crucial.

OBJECTIVES

To identify the characteristics of insoluble proteins from different sources of cerebral thrombus.

METHODS

This study included 13 patients with cardiogenic embolic (CE) thrombus and 15 with large artery atherosclerotic (LAA) thrombus. High-performance liquid chromatography and liquid chromatography-tandem mass spectrometry were used to analyze insoluble proteins in thrombi. Bioinformatics analyses explored differential proteins and associated functional pathways. Least absolute shrinkage and selection operator and random forest identified biomarkers for diagnosing thrombus sources, validated by parallel reaction monitoring.

RESULTS

We constructed an insoluble protein atlas of cerebral thrombi, identifying 6975 insoluble proteins, including 143 extracellular matrix (ECM)-related proteins. The enrichment pathways considerably varied between thrombi from different sources. Inflammation-related pathways, such as acute inflammatory response, along with ECM-related pathways such as laminin interactions, were notably upregulated in LAA compared with CE. Additionally, 2 biomarkers (IDH2 and HSPG2) exhibited strong diagnostic performance (area under the curve = 1) and robustness.

CONCLUSION

In the insoluble proteomics of thrombus, we highlighted the crucial roles of immune responses and ECM proteins in thrombus formation, providing new insights into its mechanisms and potential drug development. Additionally, we identified 2 biomarkers that offer new methods for determining thrombus sources in patients with LVO.

Smooth muscle cell-specific CD47 deletion suppresses atherosclerosis

BACKGROUND

Recent smooth muscle cell (SMC)-lineage tracing and single-cell RNA sequencing (scRNA-seq) experiments revealed a significant role of SMC-derived cells in atherosclerosis development. Further, thrombospondin-1 (TSP1), a matricellular protein, and activation of its receptor cluster of differentiation (CD) 47 have been linked with atherosclerosis. However, the role of vascular SMC TSP1-CD47 signaling in regulating VSMC phenotype and atherogenesis remains unknown.

METHODS

We investigated the role of SMC CD47 activation by TSP1 in regulating VSMC phenotype and atherosclerosis development using various in vitro cell-based assays, molecular biological techniques, immunohistological approaches, reanalysis of publicly available scRNA-seq data, and cell-specific knockout mice.

RESULTS

We observed elevated TSP1 expression in human atherosclerotic vascular tissues and VSMCs. TSP1-treated VSMCs exhibited decreased expression of contractile SMC markers (ACTA2, CNN1, and TAGLN) and increased proliferation. Additional experiments and reanalysis of the scRNA-seq dataset showed CD47 as the major TSP1 receptor in VSMCs, with its expression increased in SMC-derived modulated cells of murine atherosclerotic arteries. Knockdown of CD47 gene in human VSMCs upregulated expression of contractile SMC markers and abrogated TSP1's effects on these genes. SMC-specific Cd47 deletion in mice suppressed atherosclerotic lesion formation, reduced macrophage accumulation, and decreased necrotic area. However, no significant differences were observed in weight gain, liver and adipose tissue mass, plasma total cholesterol, and fasting blood glucose between control and SMC-restricted Cd47-deficient mice. Further experiments demonstrated increased efferocytosis of apoptotic CD47-silenced VSMCs by macrophages.

CONCLUSIONS

These findings suggest that CD47 plays a crucial role in regulating VSMC phenotype, and SMC-specific-Cd47 deletion suppresses atherosclerosis.

NEW AND NOTEWORTHY

VSMC phenotypic switching contributes to atherosclerosis development. The present study reports the novel observations that Cd47 levels are upregulated in phenotypically modulated SMCs within atherosclerotic arteries and targeted deletion of Cd47 specifically in SMCs attenuates atherosclerosis. Mechanistic in vitro investigations further showed that TSP1-CD47 signaling regulates VSMC phenotype. Therefore, targeting SMC CD47 represents a promising therapeutic target to suppress atherogenesis.

CYR61/CCN1: A novel mediator of redox response in corneal stromal cells of keratoconus

Keratoconus (KC) is a progressive, multifactorial and ectatic corneal disorder that characterized by steepening thinning of the cornea. It was previously demonstrated that oxidative stress has a strong link with KC progression. However, the molecular mechanism underlying oxidative stress response in KC remains unclear. Hence, the present study analyzed the heterogeneity of response of corneal stromal cells (CSCs) to oxidative stress in order to further illustrate how oxidative shape the pathophysiology of KC. Single-cell transcriptomics analysis revealed that CSCs demonstrated significant higher oxidative stress score in the KC group compared to the Ctrl group. The expression of oxidative markers verified by experiments illustrated elevated oxidative stress levels and insufficient antioxidant levels in CSCs of KC. In further single-cell transcriptomics analysis, we identified CYR61 to distinguish different subgroups of CSCs responding to oxidative stress. The cornea stroma cells in KC could be differentiated into CYR61high cells and CYR61low cells. Of note, the CYR61high cells showed lower score in collagen production process and higher score in collagen catabolic process. Further experiments illustrated that CYR61 was elevated in KC and associated with collagen production.

ECM Microenvironment in Vascular Homeostasis: New Targets for Atherosclerosis

Alterations in vascular extracellular matrix (ECM) components, interactions, and mechanical properties influence both the formation and stability of atherosclerotic plaques. This review discusses the contribution of the ECM microenvironment in vascular homeostasis and remodeling in atherosclerosis, highlighting Cartilage oligomeric matrix protein (COMP) and its degrading enzyme ADAMTS7 as examples, and proposes potential avenues for future research aimed at identifying novel therapeutic targets for atherosclerosis based on the ECM microenvironment.

Stress, Vascular Smooth Muscle Cell Phenotype and Atherosclerosis: Novel Insight into Smooth Muscle Cell Phenotypic Transition in Atherosclerosis

PURPOSE OF REVIEW

Our work is to establish more distinct association between specific stress and vascular smooth muscle cells (VSMCs) phenotypes to alleviate atherosclerotic plaque burden and delay atherosclerosis (AS) progression.

RECENT FINDING

In recent years, VSMCs phenotypic transition has received significant interests. Different stresses were found to be associated with VSMCs phenotypic transition. However, the explicit correlation between VSMCs phenotype and specific stress has not been elucidated clearly yet. We discover that VSMCs phenotypic transition, which is widely involved in the progression of AS, is associated with specific stress. We discuss approaches targeting stresses to intervene VSMCs phenotypic transition, which may contribute to develop innovative therapies for AS.

Matricellular proteins: Potential biomarkers in head and neck cancer

The extracellular matrix (ECM) is a complex network of diverse multidomain macromolecules, including collagen, proteoglycans, and fibronectin, that significantly contribute to the mechanical properties of tissues. Matricellular proteins (MCPs), as a family of non-structural proteins, play a crucial role in regulating various ECM functions. They exert their biological effects by interacting with matrix proteins, cell surface receptors, cytokines, and proteases. These interactions govern essential cellular processes such as differentiation, proliferation, adhesion, migration as well as multiple signal transduction pathways. Consequently, MCPs are pivotal in maintaining tissue homeostasis while orchestrating intricate molecular mechanisms within the ECM framework. The expression level of MCPs in adult steady-state tissues is significantly low; however, under pathological conditions such as inflammation and cancer, there is a substantial increase in their expression. In recent years, an increasing number of studies have focused on elucidating the role and significance of MCPs in the development and progression of head and neck cancer (HNC). During HNC progression, there is a remarkable upregulation in MCP expression. Through their distinctive structure and function, they actively promote tumor growth, invasion, epithelial-mesenchymal transition, and lymphatic metastasis of HNC cells. Moreover, by binding to integrins and modulating various signaling pathways, they effectively execute their biological functions. Furthermore, MCPs also hold potential as prognostic indicators. Although the star proteins of various MCPs have been extensively investigated, there remains a plethora of MCP family members that necessitate further scrutiny. This article comprehensively examines the functionalities of each MCP and highlights the research advancements in the context of HNC, with an aim to identify novel biomarkers for HNC and propose promising avenues for future investigations.

Glycosylation of blood cells during the onset and progression of atherosclerosis and myocardial infarction

Protein glycosylation controls cell-cell and cell-extracellular matrix (ECM) communication in immune, vascular, and inflammatory processes, underlining the critical role of this process in the identification of disease biomarkers and the design of novel therapies. Emerging evidence highlights the critical role of blood cell glycosylation in the pathophysiology of atherosclerosis (ATH) and myocardial infarction (MI). Here, we review the role of glycosylation in the interplay between blood cells, particularly erythrocytes, and endothelial cells (ECs), highlighting the involvement of this critical post/cotranslational modification in settings of cardiovascular disease (CVD). Importantly, we focus on emerging preclinical studies and clinical trials based on glycan-targeted drugs to validate their therapeutic potential. These findings may help establish new trends in preventive medicine and delineate novel targeted therapies in CVD.

Cell cycle control by cell-matrix interactions

Cell adhesion to the extracellular matrix (ECM) is required for normal cell cycle progression and accurate cell division. However, how cell adhesion to the wide range of ECM proteins found in human tissues influences the cell cycle is not fully understood. The composition and physical properties of the ECM can have profound effects on cell proliferation but can also promote cell cycle exit and quiescence. Furthermore, during tumor development and progression, changes in the ECM can drive both cancer cell proliferation and dormancy. Cell-matrix adhesion is primarily sensed via integrin-associated adhesion complexes, which in turn are regulated by the cell cycle machinery. In particular, cyclin-dependent kinase 1 (CDK1) has been shown to play a crucial role in regulating adhesion complexes during interphase and entry into mitosis. These reciprocal links between cell cycle progression and cell-matrix interactions are now being identified.

Serum Secreted Protein Acidic and Rich in Cysteine-Like 1 as a Biochemical Predictor for Prognosticating Clinical Outcomes After Acute Supratentorial Intracerebral Hemorrhage: A Prospective Cohort Study

Background

Secreted protein acidic and rich in cysteine-like 1 (SPARCL1) regulates synaptic stability and is up-regulated during axonal regeneration. Here, serum SPARCL1 was determined for estimating severity and prognosticating early neurological deterioration (END) and functional outcomes of acute intracerebral hemorrhage (ICH).

Methods

In this prospective observational cohort study of 156 patients with supratentorial ICH, blood samples of 53 were acquired not only at admission but also ad days 1, 3, 5, 7 and 10. Another group of 53 healthy controls were recruited. The modified Rankin Scale (mRS) scores of 3-6 at poststroke six months were regarded as poor prognosis.

Results

As opposed to controls, serum SPARCL1 levels were markedly elevated during the early ten days after ICH, with the highest levels at days 1 and 3. Admission serum SPARCL1 levels were independently correlated with National Institutes of Health Stroke Scale scores and hematoma volume, were significantly increased in the order of six-month mRS scores from 0 to 6 and were independently correlated with six-month mRS scores. Serum SPARCL1 levels were linearly related to risks of poor six-month prognosis and END under restricted cubic spline, had significant efficiency under receiver operating characteristic (ROC) curve and were independently associated with END and poor prognosis. Subgroup analysis confirmed that no interactions existed for associations of serum SPARCL1 levels with other variables, such as age, gender and some specific vascular risk factors. END and poor prognosis prediction models integrating serum SPARCL1 were displayed using the two nomograms. The poor prognosis prediction model, but END prediction model not, performed well under calibration curve, decision curve and ROC curve.

Conclusion

A substantial elevation of serum SPARCL1 levels during the early period after ICH is independently related to illness severity and poor neurological outcomes, thus signifying that serum SPARCL1 may appear as a prognostic biomarker of ICH.