Abstract:Phagocytosis of lipoprotein particles mediated by low density lipoprotein receptors on the surface of hepatocytes is the main pathway for the body to clear circulating low density lipoprotein, and plays a pivotal role in maintaining the homeostasis of cholesterol metabolism in the body. This article briefly reviewed the different links of low density lipoprotein receptor trafficking, including endocytosis, sorting, degradation or recycling channels of receptor molecules, and the main regulatory factors of each link, and summarized the latest advances in related fields. At present, the development of drugs indirectly targeting low density lipoprotein receptor transcriptional regulation (statins) and drugs targeting low density lipoprotein receptor degradation (proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors) have achieved tremendous success. However, our understanding of the molecular mechanisms regulating low density lipoprotein receptor trafficking remains to be incomplete, especially the intracellular recycling processes and the related signaling mechanisms need more research. It is anticipated that further in-depth research in these areas may foster the discovery of new targets for the treatment of hypercholesterolemia in the future.

Abstract:Histone methylation modification, as one of the post-translational modifications, has been increasingly shown by studies to play a crucial role in the development of cardiovascular diseases (CVD). Due to its reversibility, targeting related modifying enzymes is expected to provide new strategies for the clinical diagnosis and treatment of CVD. This article reviews the relevant methylation modifications and their important regulatory mechanisms in CVD, and discusses the research progress of histone methylation inhibitors in the cardiovascular field.

Abstract:Aim To investigate the effect of adenovirus (ADV)-mediated Profurin (PF) expression on the plaque stability of ApoE－/－ mice. Methods ApoE－/－ mice were fed with high-fat diet for 8 weeks, and then treated with ADV-mediated PF intervention, followed by high-fat diet for 4 weeks. Aortic roots were isolated for atherosclerotic plaque area analysis and immunohistochemical analysis. Plasma phospholipid transfer protein (PLTP) activity was detected by fluorescence donor essay, plasma total cholesterol (TC) and triglyceride (TG) were measured by enzyme assay kits, and fast protein liquid chromatography was used for lipoprotein profile analysis. Results Compared with the control group, the plasma TC and TG levels, PLTP activity and circulating tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels in ADV-PF group were significantly decreased (P＜0.01). In the ADV-PF group, there was no significant change in atherosclerotic lesions on the inner surface of the full-length aorta, but the plaque area and lipid area in the aortic root were reduced (P＜0.01), the content of macrophages was significantly decreased (P＜0.01), and the smooth muscle cells and collagen area were not significantly different. The content of matrix metalloproteinase-9 in plaque was significantly decreased (P＜0.05). Conclusion Overexpression of PF can alleviate atherosclerosis and reduce the levels of circulating inflammatory factors to a certain extent, and effectively improve the plaque stability of ApoE－/－ mice.

Abstract:Aim To explore the effect and mechanism of annexin A1 mimic peptide Ac2-26 on ferroptosis in human umbilical vein endothelial cells (HUVEC). Methods Induction of HUVEC ferroptosis was achieved by the classical ferroptosis agonist RSL3, with subsequent intervention by the annexin A1 mimtic peptide Ac2-26. The cell number and viability were detected by CCK-8 kit, the levels of malondialdehyde (MDA) and glutathione (GSH) were detected by ELISA, the expression of ferroptosis-related molecules and adhesion molecules was detected by Western blot, the lipid reactive oxygen species (ROS) levels were detected by C11-BODIPY fluorescent probe, and the mitochondrial reactive oxygen species (mtROS) levels were detected by MitoSOX probe. FeRhoNOX-1 fluorescent probe was used to detect intracellular Fe²＋ content, perspective microscopy was used to observe mitochondrial morphology, JC-1 fluorescent probe was used to detect mitochondrial membrane potential, kit was used to detect ATP levels, the Scratch assay was used to detect cell migration ability, and nitrate reductase assay was used to detect nitric oxide (NO) level. Results Ac2-26 inhibited RSL3-induced decrease in HUVEC viability, up-regulated the expression of suppressor of ferroptosis proteolytic carrier family 7 member 11 (SLC7A11), GPX4, and ferritin heavy chain 1 (FTH1), increased the GSH content, decreased the MDA content, reduced the generation of intracellular lipid ROS, and decreased the intracellular Fe²＋ aggregation (P＜0.05 or P＜0.01); Ac2-26 inhibited RSL3-induced damage to HUVEC mitochondrial morphology and function, up-regulated ATP content (P＜0.05) and mitochondrial membrane potential (P＜0.001); Ac2-26 inhibited RSL3-induced decrease in HUVEC migratory ability, up-regulated NO levels, inhibited intercellular adhesion molecule-1 (ICAM-1) and interleukin-1β (IL-1β) protein expression (P＜0.05 or P＜0.01). Conclusion Ac2-26 inhibits RSL3-induced ferroptosis in HUVEC and maintains mitochondrial morphology and function, as well as HUVEC function.

Abstract:Aim To investigate the role and mechanism of KLHL21 gene in myocardial infarction (MI) of mice. Methods KLHL21 gene knockout (KO) mice were generated using CRISPR/Cas9 technology, and C57BL/6 wild-type mice were used as controls. Sixty KLHL21 KO mice and 60 wild-type mice were randomly divided into four groups:WT+Sham group (n＝30), WT+MI group (n＝30), KO+Sham group (n＝30) and KO+MI group (n＝30). Postoperative ischemic and infarct areas were assessed using TTC and Evans Blue staining, myocardial injury markers were measured by ELISA, cardiac function was evaluated by ultrasound, and histological changes were examined using HE and Masson staining. Western blot was used to detect proteins related to the nuclear factor-κB (NF-κB) signaling pathway. ResultsKLHL21 protein expression in the myocardial tissue of KO mice was significantly lower than that in WT mice. The infarct area in KO+MI mice was significantly larger than that in WT+MI group. KO+MI mice showed reduced cardiac function compared with WT+MI mice. HE staining revealed myocardial cell loss, liquefactive necrosis, nuclear fragmentation, and significant neutrophil infiltration, while Masson staining showed aggravated fibrosis in KO+MI group. Serum tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), creatine kinase-MB (CK-MB), and cardiac troponin I (cTnI) levels were significantly increased in KO+MI mice compared with WT+MI mice. Western blot analysis showed increased levels of phosphorylated inhibitor of nuclear factor-κB alpha (p-IKBα), P65, and P50, and decreased nuclear factor-κB alpha (IKBα) in KO+MI mice. Conclusion KLHL21 gene plays a preventive role in myocardial infarction in mice, possibly through inhibition of NF-κB signaling pathway activation.

Abstract:Aim To investigate the effect of hydrogen sulfide on macrophage calcification and its underlying molecular mechanisms. Methods Oil red O staining was used to observe intracellular lipid accumulation, and von Kossa staining and atomic absorption spectroscopy were used for morphological and quantitative analysis of calcium deposition and intracellular calcium content in a mononuclear macrophage calcification model. Western blot and RT-PCR were used to detect the mRNA and protein expression of osteopontin (OPN) at different doses and treatment times of hydrogen sulfide.At the same time, Western blot was used to detect the expression changes of early growth response factor 1 (EGR1), endoplasmic reticulum stress-related markers C/EBP homologous protein (CHOP) and glucose-regulated protein 78 (GRP78).Reactive oxygen species levels were evaluated by fluorescence probe staining, and the effect of hydrogen sulfide on macrophage calcification was evaluated by combining von Kossa staining and calcium ion fluorescence probe staining. The molecular mechanisms of hydrogen sulfide affecting macrophage calcification were explored by interfering with EGR1 expression and using endoplasmic reticulum stress inhibitor 4-phenylbutyric acid (4-PBA). Results Compared with oxidized low density lipoprotein (ox-LDL) group, β-glycerophosphate (β-GP)＋40 g/L ox-LDL group showed a significant increase in intracellular lipid accumulation, while hydrogen sulfide significantly inhibited macrophage calcification in a concentration- and time-dependent manner. Compared with the β-GP＋ox LDL group, the most significant effect was observed after incubation with 100 μ mol/L NaHS for 4 days. The hydrogen sulfide group showed a 66% decrease in intracellular calcium content (P＜0.01), a 71% decrease in intercellular calcium deposition (P＜0.01), and a 50% and 48% decrease in OPN mRNA and protein expression, respectively (P＜0.05). Hydrogen sulfide treatment upregulated the expression of EGR1 by 21%, while downregulating the expression of CHOP and GRP78 by 58% and 59%, respectively (P＜0.01). The endoplasmic reticulum stress inhibitor 4-PBA could downregulate OPN expression by 73% (P＜0.01), while interfering with EGR1 expression completely counteracts the inhibitory effect of hydrogen sulfide on OPN expression and calcium deposition (P＜0.01). Conclusion Hydrogen sulfide significantly inhibits macrophage calcification by upregulating EGR1 expression and suppressing endoplasmic reticulum stress.

Abstract:Aim To analyze the incidence of major adverse cardiovascular and cerebrovascular events (MACCE) in patients with different types of acute coronary syndrome (ACS) undergoing coronary artery rotational atherectomy (RA) within two years. Methods 268 patients with ACS who underwent RA in the Department of Cardiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School of Nanjing University, between November 2011 and December 2022 were retrospectively included. According to whether ST-segment elevation myocardial infarction (STEMI) occurred, they were divided into 25 cases in the ST-segment elevation myocardial infarction (STEMI) group and 243 cases in the non-ST-segment elevation acute coronary syndrome (NSTE-ACS) group. The NSTE-ACS group included unstable angina pectoris (UAP) and non-STEMI (NSTEMI). The basic information and intraoperative data related to percutaneous coronary intervention (PCI) in the two groups were collected, and the occurrence of MACCE (including cardiovascular death, non fatal myocardial infarction, worsening heart failure, ischemic stroke and target vessel revascularization) within two years after RA was followed up and analyzed. Results Compared with the NSTE-ACS group, the STEMI group had a higher incidence of MACCE and cardiovascular mortality during the two-year follow-up period (10.3% and 0.4% vs. 28.0% and 8.0%; P＜0.05). There was no statistical difference between the incidence of target vessel revascularization, nonfatal infarction, ischemic stroke and worsening heart failure between the two groups (P＞0.05). According to subgroup analysis based on enrollment periods, the results showed that over time (2011-2017 compared to 2018-2022), the incidence of MACCE in all patients within two years after RA showed a decreasing trend (18.97% vs. 6.58%). Combined with previous studies, gender, hypertension, diabetes, renal insufficiency, smoking and left ventricular ejection fraction (LVEF) were included in the Cox regression model. It was found that the use of intravascular ultrasound (IVUS) was an independent factor to reduce the incidence of MACCE in ACS patients within two years after RA (HR＝0.3,5%CI:0.153～0.723, P＜0.01). Kaplan-Meier analysis showed that among ACS patients undergoing RA, the cumulative incidence of MACCE events was higher in the STEMI group than that in the NSTE-ACS group (P＜0.05). Conclusion STEMI patients have a higher incidence of MACCE and cardiovascular mortality within two years after RA compared to NSTE-ACS patients, and the use of IVUS during RA surgery can reduce the incidence of MACCE in ACS patients after RA.

Abstract:Aim Ischemic stroke (IS) is caused by acute ischemia of cerebral blood vessels, leading to brain tissue damage and neuronal apoptosis. The pathogenesis is complex, involving multiple cell death modes such as pyroptosis, ferroptosis and disulfide death. Disulfide death is a newly discovered form of death that helps to explore the pathological mechanisms of various diseases from a new perspective. The aim of this study is to discover and validate the differential expression of disulfide death-related genes in blood samples of ischemic patients and their association with immune regulation. Methods The relevant datasets of clinical patients (GSE16561 and GSE37587) were obtained through online big data. Differentially expressed genes related to disulfide death were identified, and gene enrichment analysis was conducted to further explore the potential mechanisms. Subsequently, immune cell infiltration was analyzed to investigate the dysregulation of immune cells in the context of IS. Finally, the accuracy of key genes was verified through ROC curves, column charts, calibration curves, and decision curves, and a disease prediction model was constructed to predict the risk of stroke. Results Based on this dataset, significant differential expression of 9 genes related to disulfide death was identified. Independent external validation was conducted using the microarray dataset GSE58294. Single item comparisons were performed on these differentially expressed genes in blood samples from 69 IS patients and 23 normal individuals.The results showed that the trends of LRPPRC, MYH9, NDUFA11, PRDX1 and RPN1, the 5 differentially expressed genes, were consistent. Immune infiltration analysis found that differentially expressed genes such as TLN1, MYH9, PRDX1, LRPPRC, NDUFA11 were also strongly correlated with CD8＋T cells, activated NK cells, macrophages, and neutrophils in IS patients. Functional enrichment analysis emphasized the important role of pathways such as focal adhesion, platelet aggregation, and activation in the occurrence and development of diseases. By using a column chart model for risk prediction, it was shown that the accuracy of these differentially expressed genes was good, and the ROC curve AUC value of the optimized combination of disulfide death-related genes could reach 0.844. Further validation through an external dataset (GSE58294) revealed that the ROC curve AUC value optimized for disulfide death-related genes reached 0.989, which had good clinical guidance significance for the risk of IS. Conclusions This study confirmed the existence of 5 disulfide death-related genes in IS patients through a dataset, including upregulation of MYH9 and downregulation of LRPPRC, NDUFA11, PRDX1 and RPN1. These gene alterations are suggested to influence IS disease progression and prognosis through immune inflammation and bleeding risk.

Abstract:Aim To explore the correlation between methylation rate of different cytosine-phosphate-guanine (CpG) sites in the Furin promoter region and blood lipids in non-diabetic adults. Methods This study was a cross-sectional study. The study population was non-diabetic adults from the Gusu cohort. The methylation rates of the eight CpG sites in the Furin promoter region, blood glucose, blood lipids, blood pressure and other assays in this population at baseline were collected, and the correlation between the methylation rates of these sites and blood lipids were investigated by variance analysis and Logistic regression models. The E-value was used to evaluate the robustness of the relationship between methylation rates of the CpG sites and blood lipids. Results The methylation rates of CpG sites in Furin promoter region were only correlated with the level of total cholesterol (TC). The methylation rate of CpG4 site was lower in TC increased group than that in normal group (P＜0.05). Multivariate Logistic regression analysis showed that methylation rate at CpG2 site (with a change of 10%) was independently correlated with elevated blood TC (OR=1.2,5%CI:1.05～2.51, P=0.031). After adjusting for relevant covariates, the methylation rate of CpG2 was still positively correlated with elevated TC in subgroups of different ages/genders. The E-value calculated according to the correlation between the methylation rate of CpG2 and the risk of elevated TC in the multifactorial analysis was 2.62, which supported the robustness of this relationship. Conclusion Elevated methylation rate of CpG2 site in the Furin promoter region is an independent risk factor for elevated blood TC. This site may be a potential target for regulating blood TC.

Abstract:Atherosclerosis (As) is one of the main causes of death in the global population. The main causes are hyperlipidemia, hypertension, obesity, etc. However, after avoiding traditional risks, As may still progress. In recent years, the role of microbial infection factors in As has been increasingly valued. This article reviews the correlation between infection and As, and focuses on introducing the research progress on the mechanisms by which microbial infections such as Helicobacter pylori, Chlamydia pneumoniae, human immunodeficiency virus (HIV), and cytomegalovirus promote the development of As, aiming to discover the correlation between microbial infections and As and provide new ideas for the prevention and treatment of As.

Abstract:Triglyceride (TG) is transported in the blood as specific triglyceride-rich lipoprotein (TRL). When TRL is overproduced or the catabolism is not timely, cholesterol ester-rich residues is formed. Both TRL and its residues contribute to the development of atherosclerosis (As) through various direct and indirect mechanisms. Currently, the combination of lifestyle interventions and Western medicines is considered the preferred treatment strategy for As. However, lipid-lowering therapy alone cannot fully eliminate the residual risk of As. In contrast, traditional Chinese medicine emphasizes the holistic regulation of bodily functions to prevent and treat As. This paper will begin by examining the metabolic mechanisms of TRL, elucidate the role of TRL and its residues in the risk of As occurrence, and summarize current strategies targeting the TRL metabolic pathway to reduce the incidence of As.

Abstract:The incidence of cardiovascular diseases (CVD) has been increasing year by year, with atherosclerosis (As) being the leading cause in terms of both incidnce and mortality for CVD in China. Traditional theories suggest that the pathogenesis of atherosclerotic CVD is associated with endothelial dysfunction and inflammatory responses caused by the accumulation of oxidized low density lipoprotein (ox-LDL). However, recent studies have demonstrated that perivascular adipose tissue (PVAT) can positively influence the occurrence and development of CVD through the vascular adventitia pathway. This article reviews the connection between PVAT and CVD, effective pathways for promoting CVD improvement, and the regulatory role of AMP-activated protein kinase (AMPK) on PVAT, aiming to explore effective intervention targets for CVD.