Clinical Risk Factors and Plaque Characteristics Associated with New Development of Contralateral Stenosis in Patients Undergoing Carotid Endarterectomy

Transcriptomic analysis reveals the critical role of chemokine signaling in the anti-atherosclerosis effect of Xuefu Zhuyu decoction

ETHNOPHARMACOLOGICAL RELEVANCE

The process of atherosclerosis (AS) is complicated. Transcriptomics technology can assist in discovering the underlying mechanisms and exploring the key targets of Traditional Chinese Medicine (TCM) against atherosclerosis.

AIM

This study aimed to investigate targets and signaling pathways significantly related to AS and the potential intervention targets of Xuefu Zhuyu decoction by transcriptomics.

MATERIALS AND METHODS

AS models were established by subjecting ApoE-/-mice to an 8-week high-fat diet. Structural changes and plaque formation in the aortic root were observed using hematoxylin-eosin staining (HE staining), while Oil Red O staining was employed to visualize lipid deposition within the aortic root plaque. Movat staining and immunohistochemical staining were conducted to examine the components present in the aortic root plaque. Macrophage content within the plaque was observed through immunofluorescence. Additionally, mRNA sequencing was performed on aortic tissues to identify differentially expressed genes. Enrichment analysis was performed using GO and KEGG analysis. Visualization of the protein-protein interaction (PPI) network was achieved using Cytoscape 3.7.1 and STRING. Western blotting (WB) was employed to assess the protein expression of major differentially expressed genes in the aortic tissue. The drug freeze-dried powder of Xuefu Zhuyu decoction was prepared and the RAW264.7 cells were induced by lipopolysaccharide (LPS) to build an in vitro model. Real-time quantitative PCR was employed to measure the mRNA expression of major differential genes.

RESULTS

After ApoE-/- mice were fed with an 8-week high-fat diet, observable changes included the thinning of the aortic root wall, the accumulation of foam cells within the plaque, and the formation of cholesterol crystals in the model group. Treatment with Xuefu Zhuyu (XFZY) decoction for 12 weeks significantly reduced the lipid deposition and the number of macrophages (P < 0.05) and significantly increased the collagen content within the plaque (P < 0.01). Enrichment analysis revealed a high enrichment of the Cytokine-cytokine receptor interaction pathway and Chemokine signaling pathway. Noteworthy genes involved in this response included Ccl12, Ccl22, Cx3cr1, Ccr7, Ccr2, Tnfrsf25, and Gdf5. Xuefu Zhuyu decoction significantly downregulated the expression of CX3CL1 and CX3CR1 (P < 0.05) and upregulated the expression of GDF5 (P < 0.01). Compared with control group, in cell models, the mRNA expressions of Ccl12, Ccl22, and Ccr2 were significantly upregulated (P < 0.05 or P < 0.01). Xuefu Zhuyu decoction significantly downregulated the expression of Ccl12, Ccl22, Cx3cr1, Ccr7 and Ccr2 (P < 0.05 or P < 0.01).

CONCLUSION

Xuefu Zhuyu decoction demonstrates effective regulation of plaque components, retarding plaque progression and preserving plaque stability by modulating lipid metabolism and inflammatory responses. Subsequent transcriptome analysis identified the Cytokine-cytokine receptor interaction and Chemokine signaling pathway as potential key pathways for the therapeutic effects of Xuefu Zhuyu decoction. This insight not only provides crucial avenues for further exploration into the mechanisms underlying Xuefu Zhuyu decoction but also offers valuable perspectives and hypotheses for enhancing disease prevention and treatment strategies.

Increased Piezo1 expression in myofibroblasts in patients with symptomatic carotid atherosclerotic plaques undergoing carotid endarterectomy: A pilot study

OBJECTIVES

We aimed to investigate Piezo1 expression in myofibroblasts in symptomatic and asymptomatic patients undergoing carotid endarterectomy and its relationship with atherosclerotic plaque formation.

METHODS

This cross-sectional study analyzed carotid plaques of 17 randomly selected patients who underwent carotid endarterectomy from May 2015 to August 2017. In total, 51 sections (the most stenotic lesion, and the sections 5-mm proximal and distal) stained with hematoxylin-eosin and elastica-Masson were examined. Immunohistochemistry was performed using antibodies to Piezo1. The Piezo1 score of a section was calculated semiquantitatively, averaged across 30 randomly selected myofibroblasts in the fibrous cap of the plaque.

RESULTS

Of 17 patients (mean age: 74.2 ± 7.1 years), 15 were men, 9 had diabetes mellitus, and 13 had hypertension. Symptomatic patients had higher mean Piezo1 score than asymptomatic patients (1.78 ± 0.23 vs 1.34 ± 0.17, p < .001). Univariate linear regression analyses suggested an association between plaque rupture, thin-cap fibroatheroma and microcalcifications and the Piezo1 score (p = .001, .008, and 0.003, respectively).

CONCLUSIONS

Increased Piezo1 expression of myofibroblasts may be associated with atherosclerotic carotid plaque instability. Further study is warranted to support this finding.

Botanical Antcin K Alleviates High-Fat Damage in Palm Acid Oil-Treated Vascular Endothelial Cells and Macrophages

Lipid metabolism disorder is the most critical risk factor for atherosclerosis, and the process involves lipid deposition in the arterial intima. In Taiwan, antcin K, an active triterpenoid from the fruiting bodies of Antrodia camphorata, has been considered a potential lipid-lowering agent. Despite this, the possible therapeutic mechanisms of antcin K remain unclear. To explore the crucial role of botanical antcin K in reducing atherosclerotic plaque, we used SVEC4-10 vascular endothelial cells and RAW264.7 macrophages with palm acid oil-induced high-fat damage as our cell models. Our results showed through using the DPPH assay that antcin K had excellent free radical scavenging ability. Antcin K treatment can significantly alleviate the high-fat damage and reduce the levels of inflammatory factors of TNF-α and IL-1β in vascular endothelial cells and macrophages, as shown through MTT assay and ELISA. Furthermore, antcin K treatment can effectively enhance migration ability and clear lipid deposition in macrophages, as shown by using cell migration assay and oil red O staining. When stained with immunofluorescence, antcin K was shown to significantly decrease the expression of adhesion molecules of vascular cell adhesion molecule 1 (VCAM-1) in vascular endothelial cells involved in monocyte migration and inflammation. Antcin K not only reduced the expression of the CD36 scavenger receptor but also augmented the expression of Kruppel-like factor 4 (KLF4) transcription factor in macrophages, which inhibits the transformation of macrophages into foam cells underlying the pathological process of atherosclerosis. Taking our findings into account, we suggested that botanical antcin K could have therapeutic potential for the treatment of atherosclerosis.

A systematic review of contralateral carotid stenosis progression after carotid endarterectomy

OBJECTIVE

Progression of contralateral carotid artery stenosis after carotid endarterectomy (CEA) has been described by several authors. The aim of this study is to determine such disease progression and its related transient ischemic attacks (TIAs) or strokes by reviewing the existing literature.

METHODS

We performed a systematic literature review to select randomized controlled trials and observational studies reporting outcomes of patients treated by CEA and with concomitant contralateral carotid stenosis, regardless its degree of stenosis. The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO registration number: CRD42019127595). The primary study end point was the progression of contralateral carotid artery stenosis after CEA, and the secondary end point was incidence of TIAs and strokes owing to contralateral carotid stenosis.

RESULTS

Seventeen studies were retrieved, reporting data on a total of 7679 patients who had undergone CEA, in particular they were one post hoc analysis of a randomized controlled trial, nine prospective, and seven retrospective observational studies. Among these patients, follow-up information on the contralateral carotid artery was available for 5454 cases. Disease progression was observed in 18% of patients: single class progression from mild (<50%) and from moderate (50%-70%) stenosis was observed in 15% and 23% of cases, respectively. We found 105 TIAs (4%) and 88 strokes (3%) among 2781 patients with stenosis progression, based on result from 11 studies.

CONCLUSIONS

We found a progression of contralateral carotid stenosis in a significant number of patients treated with CEA and with baseline carotid stenosis. This systematic literature review suggests that patients with moderate contralateral carotid stenosis demonstrate more rapid progression to significant or symptomatic stenosis than patients with mild contralateral stenosis.

Vascular Macrophages in Atherosclerosis

Atherosclerosis is the main pathological basis for the occurrence of most cardiovascular diseases, the leading global health threat, and a great burden for society. It has been well established that atherosclerosis is not only a metabolic disorder but also a chronic, sterile, and maladaptive inflammatory process encompassing both innate and adaptive immunity. Macrophages, the major immune cell population in atherosclerotic lesions, have been shown to play critical roles in all stages of atherosclerosis, including the initiation and progression of advanced atherosclerosis. Macrophages have emerged as a novel potential target for antiatherosclerosis therapy. In addition, the macrophage phenotype is greatly influenced by microenvironmental stimuli in the plaques and presents complex heterogeneity. This article reviews the functions of macrophages in different stages of atherosclerosis, as well as the phenotypes and functions of macrophage subsets. New treatment strategies based on macrophage-related inflammation are also discussed.

Macrophage complexity in human atherosclerosis: opportunities for treatment?

PURPOSE OF REVIEW

The pivotal role of macrophages in experimental atherosclerosis is firmly established, but their contribution to human disease is less well defined. In this review we have outlined the current insights on macrophage phenotypes and their presumed precursors, monocytes, in clinical atherosclerosis, and their association with disease progression. Moreover, we will assess major clinical modifiers of macrophage-mediated plaque inflammation and define the outstanding questions for further study.

RECENT FINDINGS

Our survey indicates that macrophage accumulation and status in human plaques are linked with lesion progression and destabilization as well as with symptomatic coronary artery disease. Likewise, levels of their precursors, circulating monocytes were repeatedly seen to associate with atherosclerosis and to predict clinical outcome. Furthermore, the presence and phenotype of both macrophages and monocytes appears to be responsive to the traditional risk factors of atherosclerosis, including hypercholesterolemia, hypertension, and type 2 diabetes, and to treatment thereof, with clear repercussions on disease development.

SUMMARY

Although plaque macrophages and their precursor cells do represent attractive targets for treating cardiovascular diseases, this therapeutic avenue requires much deeper understanding of the complexity of macrophage biology in human atherosclerosis than available at present.