Intracranial atherosclerosis （ICAS） is the main cause of ischemic stroke in the world. In clinical practice， ICAS is mainly identified through imaging examinations. In recent years， high-resolution magnetic resonance vessel wall imaging （HRMR-VWI） has gradually become an important means for evaluating the characteristics of ICAS plaques. The application of HRMR-VWI has increased the accuracy in identifying the pathogenesis of acute ischemic stroke， providing a reference for the secondary prevention and clinical individualized treatment of stroke. This article systematically reviews the imaging manifestations of the main components of ICAS plaques on HRMR-VWI， summarizes the progress on HRMR technology， and discusses the relationship between intracranial arterial plaque characteristics and stroke occurrence and recurrence as well as the relationship between plaque characteristics and stroke mechanisms， aiming to provide a basis for the diagnosis and treatment of ICAS-related ischemic stroke.
Atherosclerosis

As a serious cardiovascular disease, atherosclerosis (AS) causes chronic inflammation and oxidative stress in the body and poses a threat to human health. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a member of the phospholipase A2 (PLA2) family, and its elevated levels have been shown to contribute to AS. Lp-PLA2 is closely related to a variety of lipoproteins, and its role in promoting inflammatory responses and oxidative stress in AS is mainly achieved by hydrolyzing oxidized phosphatidylcholine (oxPC) to produce lysophosphatidylcholine (lysoPC). Moreover, macrophage apoptosis within plaque is promoted by localized Lp-PLA2 which also promotes plaque instability. This paper reviews those researches of Chinese medicine in treating AS via reducing Lp-PLA2 levels to guide future experimental studies and clinical applications related to AS.
Humans ; 1-Alkyl-2-acetylglycerophosphocholine Esterase ; Medicine, Chinese Traditional ; Atherosclerosis/drug therapy* ; Lipoproteins ; Plaque, Atherosclerotic ; Biomarkers

Objective To investigate the risk factors for the early progression of atherosclerosis，whether hyperhomocysteinemia （HHcy） is an independent risk factor for the early progression of atherosclerosis， and whether the reduction in homocysteine （Hcy） can delay the early progression of atherosclerosis. Methods The villagers，aged ≥40 years， from Liulin Town of Hanzhong City， Shaanxi Province， China were selected for structured inquiry， carotid ultrasound examination， and blood test in May 2017 and June 2020. Ultrasound examination was performed to measure carotid intima-media thickness （CIMT）， carotid plaque， and carotid stenosis rate to reflect the degree of arteriosclerosis. Results A total of 500 individuals were included in the final analysis， among whom 451 had no CIMT thickening at baseline， 429 had no carotid plaque at baseline， and 454 had no carotid stenosis at baseline. After 3 years of follow-up， among the 500 individuals， 176 （35.2%） had CIMT thickening， and the multivariate analysis showed that old age， smoking， and a high level of low-density lipoprotein cholesterol （LDL-C） were independent risk factors for CIMT thickening； 252 （50.4%） had new-onset plaques， and the multivariate analysis showed that old age， hypertension， and high LDL-C were independent risk factors for plaque formation； 231（46.2%） had new-onset carotid stenosis， and the multivariate analysis showed that old age， high LDL-C， and elevated triglyceride were independent risk factors for carotid stenosis. There were 364 patients with HHcy （≥15 μmol/L） in the initial examination， and after 3 years， 119 had a reduction in Hcy， while 245 had no reduction in Hcy. After adjustment for sex， previous stroke， smoking， baseline LDL-C， baseline Hcy， and Hcy after 3 years， the multivariate analysis showed that neither HHcy nor the reduction in Hcy was associated with carotid atherosclerosis. Conclusion Old age， high LDL-C， smoking， and hypertension are the main risk factors for atherosclerosis in villagers aged ≥40 years in rural areas of Hanzhong City in Shaanxi Province. There is no significant association between HHcy and carotid atherosclerosis， and the reduction in Hcy cannot delay or reverse the process of carotid atherosclerosis.
Atherosclerosis ; Homocysteine

Atherosclerosis is the main etiology of tandem occlusion in patients with acute ischemic stroke， with the possible mechanisms of in situ thrombosis due to atherosclerosis or distal arterial embolization due to the dislodgment of partial thrombi or plaques. The atherosclerotic elements identified within the thrombus or emboli can help with the diagnosis of the etiology of occlusion and the evaluation of plaques. This article reports a case of acute ischemic stroke due to tandem occlusion of the right anterior circulation， and the dislodgment of thrombi occurred during internal carotid artery angioplasty. The pathological analysis of the thrombi revealed a large amount of cholesterol crystals， which helped with the etiological classification of stroke and the evaluation of plaques.
Atherosclerosis

Atherosclerosis is a chronic inflammatory disease of vascular walls with a complex etiology. In recent years, the incidence of atherosclerosis continues to increase with obesity and diabetes as major risk factors. As an important metabolic organ in the body, adipose tissue also has a powerful endocrine function. In the case of obesity and diabetes, various cytokines and exosomes derived from adipose tissue mediate organ-organ/cell-cell crosstalk, and are involved in the occurrence and development of various diseases. As an important intercellular communicator, exosomes regulate the pathological process of various cardiovascular diseases and are closely related to atherosclerosis. In this paper, we reviewed the mechanism of adipose-derived exosomes in atherosclerosis with focus on endothelial dysfunction, inflammatory response, lipid metabolism disorder and insulin resistance, hoping to provide reference for the research, diagnosis and treatment of atherosclerosis.
Humans ; Exosomes/metabolism* ; Atherosclerosis ; Obesity/complications* ; Adipose Tissue/metabolism* ; Insulin Resistance

The present study aimed to investigate the protective effect of S-propargyl-cysteine (SPRC) on atherosclerosis progression in mice. A mouse model of vulnerable atherosclerotic plaque was created in ApoE^-/- mice by carotid artery tandem stenosis (TS) combined with a Western diet. Macrophotography, lipid profiles, and inflammatory markers were measured to evaluate the antiatherosclerotic effects of SPRC compared to atorvastatin as a control. Histopathological analysis was performed to assess the plaque stability. To explore the protective mechanism of SPRC, human umbilical vein endothelial cells (HUVECs) were cultured in vitro and challenged with oxidized low-density lipoprotein (ox-LDL). Cell viability was determined with a Cell Counting Kit-8 (CCK-8). Endothelial nitric oxide synthase (eNOS) phosphorylation and mRNA expression were detected by Western blot and RT-qPCR respectively. The results showed that the lesion area quantified by en face photographs of the aortic arch and carotid artery was significantly less, plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were reduced, plaque collagen content was increased and matrix metalloproteinase-9 (MMP-9) was decreased in 80 mg/kg per day SPRC-treated mice compared with model mice. These findings support the role of SPRC in plaque stabilization. In vitro studies revealed that 100 μmol/L SPRC increased the cell viability and the phosphorylation level of eNOS after ox-LDL challenge. These results suggest that SPRC delays the progression of atherosclerosis and enhances plaque stability. The protective effect may be at least partially related to the increased phosphorylation of eNOS in endothelial cells.
Animals ; Humans ; Mice ; Atherosclerosis ; Cholesterol/metabolism* ; Cysteine/pharmacology* ; Human Umbilical Vein Endothelial Cells/metabolism* ; Lipoproteins, LDL/pharmacology* ; Nitric Oxide Synthase Type III/metabolism* ; Phosphorylation ; Plaque, Atherosclerotic/pathology*

Humans ; Trained Immunity ; Atherosclerosis ; Macrophages

OBJECTIVE: To investigate the effect of microRNA-509-3p (miR-509-3p) on the apoptosis of atherosclerotic vascular endothelial cells. METHODS: Mouse aortic endothelial cells (MAECs) were divided into normal control group, oxidized low-density lipoprotein (ox-LDL) group, miR-509-3p overexpression group, miR-509-3p overexpression control group, miR-509-3p inhibitor + ox-LDL group, and miR-509-3p inhibitor control + ox-LDL group. MAEC were induced with 100 mg/L ox-LDL for 24 hours, and then transfected with miR-509-3p overexpression/inhibitor and corresponding control for 48 hours. The miR-509-3p expression in MAECs exposed to ox-LDL was detected using real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). Flow cytometry was used to detect the level of apoptosis, and cell counting kit (CCK-8) was used to detect the proliferation activity of MAECs. The direct gene targets of miR-509-3p were predicted using bioinformatics analyses and confirmed using a dual luciferase reporter assay. The expression of Bcl-2 mRNA and protein was detected by RT-qPCR and Western blotting, respectively. RESULTS: Compared with the normal control group, miR-509-3p was significantly upregulated in ox-LDL-stimulated MAECs (1.68±0.85 vs. 1.00±0.30, t = 2.398, P < 0.05). After transfection of MAECs with miR-509-3p overexpression, the luciferase activity of the BCL2 3'UTR WT reporter gene was significantly lower than that of miR-509-3p overexpression control group (0.83±0.06 vs. 1.00±0.07, t = 4.531, P = 0.001). The luciferase activity of the BCL2 3'-UTR mutant (MUT) reporter gene was not significantly different from that of miR-509-3p overexpression control group (0.94±0.05 vs. 1.00±0.08, t = 1.414, P = 0.188). Compared with the normal control group and miR-509-3p mimics control group, the cell proliferation activity was decreased [(0.60±0.06)% vs. (1.00±0.09)%, (0.89±0.04)%, both P < 0.01], the percentage of apoptotic cells were increased [(23.46±2.02)% vs. (7.66±1.52)%, (10.40±0.78)%, both P < 0.05], and the mRNA and protein expression of Bcl-2 were significantly downregulated (Bcl-2 mRNA: 0.52±0.13 vs. 1.00±0.36, 1.10±0.19, Bcl-2 protein: 0.42±0.07 vs. 1.00±0.11, 0.93±0.10, both P < 0.01) in miR-509-3p overexpression group. Compared with the ox-LDL group, inhibition of miR-509-3p expression could increase the proliferation activity of MAECs induced by ox-LDL [(0.64±0.35)% vs. (0.34±0.20%)%, P < 0.05], and reduce the apoptosis rate [(13.59±2.22)% vs. (29.84±5.19)%, P < 0.01], and up-regulated the expression of Bcl-2 mRNA and protein in MAECs induced by ox-LDL (Bcl-2 mRNA relative expression: 0.82±0.09 vs. 0.52±0.10, Bcl-2 protein relative expression: 0.83±0.17 vs. 0.40±0.07, both P < 0.05). CONCLUSIONS Bcl-2 was one of the target genes of miR-509-3p. miR-509-3p can reduce the proliferation activity of endothelial cells, reduce the expression of Bcl-2, and promote cell apoptosis, thereby promoting the occurrence and development of atherosclerosis. Inhibition of miR-509-3p expression may be a potential therapeutic target for atherosclerosis.
Animals ; Mice ; Humans ; Endothelial Cells ; MicroRNAs/metabolism* ; Signal Transduction ; Lipoproteins, LDL/metabolism* ; Apoptosis ; RNA, Messenger/metabolism* ; Proto-Oncogene Proteins c-bcl-2/pharmacology* ; Atherosclerosis/metabolism* ; Luciferases/pharmacology* ; Cell Proliferation ; Human Umbilical Vein Endothelial Cells

Gut microbiota dysbiosis is an avenue for the promotion of atherosclerosis (AS) and this effect is mediated partly via the circulating microbial metabolites. More microbial metabolites related to AS vascular inflammation, and the mechanisms involved need to be clarified urgently. Paeonol (Pae) is an active compound isolated from Paeonia suffruticoas Andr. with anti-AS inflammation effect. However, considering the low oral bioavailability of Pae, it is worth exploring the mechanism by which Pae reduces the harmful metabolites of the gut microbiota to alleviate AS. In this study, ApoE^-/- mice were fed a high-fat diet (HFD) to establish an AS model. AS mice were administrated with Pae (200 or 400 mg·kg^-1) by oral gavage and fecal microbiota transplantation (FMT) was conducted. 16S rDNA sequencing was performed to investigate the composition of the gut microbiota, while metabolomics analysis was used to identify the metabolites in serum and cecal contents. The results indicated that Pae significantly improved AS by regulating gut microbiota composition and microbiota metabolic profile in AS mice. We also identified α-hydroxyisobutyric acid (HIBA) as a harmful microbial metabolite reduced by Pae. HIBA supplementation in drinking water promoted AS inflammation in AS mice. Furthermore, vascular endothelial cells (VECs) were cultured and stimulated by HIBA. We verified that HIBA stimulation increased intracellular ROS levels, thereby inducing VEC inflammation via the TXNIP/NLRP3 pathway. In sum, Pae reduces the production of the microbial metabolite HIBA, thus alleviating the ROS/TXNIP/NLRP3 pathway-mediated endothelial inflammation in AS. Our study innovatively confirms the mechanism by which Pae reduces the harmful metabolites of gut microbiota to alleviate AS and proposes HIBA as a potential biomarker for AS clinical judgment.
Animals ; Mice ; Atherosclerosis/drug therapy* ; Diet, High-Fat ; Endothelial Cells ; Inflammation/drug therapy* ; Mice, Inbred C57BL ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Reactive Oxygen Species

BACKGROUND: Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) are the main causes of restenosis (RS) in diabetic lower extremity arterial disease (LEAD). However, the relevant pathogenic mechanisms are poorly understood. METHODS: In this study, we introduced a "two-step injury protocol" rat RS model, which started with the induction of atherosclerosis (AS) and was followed by percutaneous transluminal angioplasty (PTA). Hematoxylin-eosin (HE) staining and immunohistochemistry staining were used to verify the form of RS. Two-step transfection was performed, with the first transfection of Lin28a followed by a second transfection of let-7c and let-7g, to explore the possible mechanism by which Lin28a exerted effects. 5-ethynyl-2΄-deoxyuridine (EdU) and Transwell assay were performed to evaluate the ability of proliferation and migration of VSMCs. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to detect the expression of Lin28a protein and let-7 family members. RESULTS: Using a combination of in vitro and in vivo experiments, we discovered that let-7c, let-7g, and microRNA98 (miR98) were downstream targets of Lin28a. More importantly, decreased expression of let-7c/let-7g increased Lin28a, leading to further inhibition of let-7c/let-7g. We also found an increased level of let-7d in the RS pathological condition, suggesting that it may function as a protective regulator of the Lin28a/let-7 loop by inhibiting the proliferation and migration of VSMCs. CONCLUSION These findings indicated the presence of a double-negative feedback loop consisting of Lin28a and let-7c/let-7g, which may be responsible for the vicious behavior of VSMCs in RS.
Rats ; Animals ; Down-Regulation ; MicroRNAs/metabolism* ; Feedback ; Cell Proliferation/genetics* ; Atherosclerosis