Abstract:Circular RNA (circRNA) is a novel class of endogenous non-coding RNA with complex biological functions, participating in various physiological and pathological processes. Due to their relatively stable stucture and tissue-specific and temporal expression patterns, circRNA have become a recent focus of biomedical research. Heart failure (HF) is characterized by impaired ventricular filling and/or ejection function caused by primary myocardial injury and cardiac overload, leading to the inability of the heart to meet the metabolic demands of the body’s tissues. It is the end stage of numerous cardiac diseases. Studies have found that circRNA may play a crucial regulatory role in the progression of HF, particularly in cardiomyocyte hypertrophy, cardiomyocyte apoptosis, autophagy and myocardial fibrosis. This review summarizes the formation, classification, functional forms, and roles in HF of circRNA, aiming to provide new insights for the prevention and treatment of HF.

Abstract:Aim To investigate the effect of theaflavin on oxidized low density lipoprotein (ox-LDL)-induced foam cell formation and oxidative stress in THP-1 macrophages and its mechanism. Methods THP-1 derived macrophages were pretreated with 50 μmol/L theaflavin and (or) 10 μmol/L nuclear factor erythroid 2-related factor 2 (NRF2) inhibitor ML385, then 100 mg/L ox-LDL was added to the cells for 24 h to establish the foam cell model. The effect of theaflavin on THP-1 macrophages viability was evaluated by CCK-8 assay and LDH release. The expression of inflammatory cytokines interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot. The release of inflammatory cytokines were detected by enzyme linked immunosorbent assay (ELISA). Intracellular lipid accumulation was detected by Oil red O staining, and lipid absorption was observed by DiL-labeled oxidized low density lipoprotein (DiL-ox-LDL) staining. Reactive oxygen species (ROS) level was detected by DCFH-DA probe. The expression of lipid uptake, cholesterol efflux and oxidative stress-related proteins were detected by Western blot and RT-qPCR. Results Treatment with 100 mg/L ox-LDL significantly decreased cell viability and cholesterol efflux-related protein expressions, increased lipid uptake, accumulation and lipid uptake-related protein expressions, and significantly promoted inflammation and ROS level, as well as the expressions of myeloperoxidase (MPO), NADPH oxidase 2 (NOX2) in THP-1 macrophages (all P＜0.05). After pretreatment with theaflavin, cell viability was increased, intracellular lipid uptake, accumulation and lipid uptake-related protein expressions were significantly reduced, cholesterol efflux-related protein expressions were significantly increased, the expression and release of IL-6, IL-1β and TNF-α were significantly decreased, ROS level was significantly decreased, and the expression of MPO and NOX2 were decreased (all P＜0.05). Pretreatment with theaflavin effectively alleviated intracellular oxidative stress by altering the expression of NRF2, heme oxygenase-1 (HO-1) and Kelch-like ECH-associated protein 1 (KEAP1) in NRF2 signaling pathway, and enhanced the translocation of NRF2 into the nucleus. After pretreatment with ML385, the expression levels of NRF2, HO-1, KEAP1 and CD36 were significantly decreased. ConclusionTheaflavin can significantly inhibit ox-LDL-induced foam cell formation, inflammation, and oxidative stress through NRF2/HO-1 signaling pathway in THP-1 macrophages.

Abstract:Aim To investigate the effect and mechanism of hydrogen molecule on myocardial injury in severe traumatic brain injury (TBI) rats. Methods Using the fluid percussion injury (FPI)-induced TBI model. 72 SD rats were randomly divided into sham group, TBI group and hydrogen molecule-treated group, with 24 rats in each group, and the rats were executed at 48 h after the operation. HE staining was used to observe the myocardial injury and the infiltration of granulocytes, ELISA was used to detect the level of superoxide dismutase (SOD), Western blot was used to detect the expression of inflammation-related factors myeloperoxidase (MPO) and heme oxygenase-1 (HO-1) protein, RT-qPCR was used to detect the levels of cardiac troponin T (cTnT), inhibitory factor-1 (IF-1), NADH/ubiquinone oxidoreductase core subunit S7 (NDUFS7), nicotinamide adenine dinucleotide phosphate (NADP) and reduced nicotinamide adenine dinucleotide phosphate (NADPH). The changes of post-traumatic echocardiography and the 7-day survival rate and body weight in the rats were observed and recorded. Results Compared with the sham group, rats in the TBI group had significantly higher troponin levels, and the echocardiographic results showed higher left ventricular end-diastolic diameter (LVEDD) and significantly lower left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), and the above pathologic changes were significantly improved after treatment with the hydrogen molecule. Myocardial tissue was disorganized with erythrocyte infiltration, and myocardial fibers were infiltrated with granulocytes in the section, which were improved in the hydrogen molecule-treated group. The body weight of the rats decreased dramatically after the operation, and about 5 days later dropped to the lowest level, and then showed a trend of slow recovery. mNSS scores showed that the neurological function of the rats was severely impaired after TBI, and the postoperative myocardial tissues showed an increase in the expression levels of MPO and HO-1 proteins and a decrease in the expression levels of SOD, and the above pathological changes were significantly improved by hydrogen molecule treatment. In the TBI group, the expression levels of NADPH, IF-1 and NDUFS7 were reduced, and the expression levels of the above indicators were significantly increased after hydrogen molecule treatment. Conclusion Hydrogen molecule may be able to increase mitochondrial energy metabolism in cardiomyocytes and reduce myocardial oxidative stress by synergistically enhancing the protein expression of IF-1 and NDUFS7 on the mitochondrial oxidative respiratory chain to increase cardiac function and survival rate in the acute phase of TBI.

Abstract:Aim To investigate the impact of bakuchiol (BAK) on lipid accumulation in macrophage-derived foam cell and explore the underlying mechanisms. Methods MTT assay was used to determine the non-toxic concentration of BAK on foam cell. Oil red O staining, NBD cholesterol, and Dil-ox-LDL were used to assess lipid accumulation in foam cell. RT-qPCR and Western blot were utilized to measure mRNA and protein expression, respectively. Results BAK promoted cholesterol effux and reduced lipid accumulation in foam cell. BAK upregulated the mRNA and protein expression levels of ATP-binding cassette transporter A1 (ABCA1) and concurrently downregulated the phosphorylation levels of extracellular signal-regulated kinase 1/2 (ERK1/2). Treatment with the ERK1/2 activator Ro 67-7476 resulted in decreased ABCA1 protein expression compared with the BAK-treated group. Conclusion BAK reduced lipid accumulation in foam cell by inhibiting ERK1/2 phosphorylation, upregulating ABCA1 expression, and promoting cholesterol efflux, thereby suppressing foam cell formation.

Abstract:Aim To explore the influencing factors of major adverse cardiovascular events (MACE) after drug-eluting stent (DES) implantation in young and middle-aged patients with coronary artery disease (CAD). Methods Retrospective study data from the First Affiliated Hospital of Zhengzhou University were extracted from the Dryad database, and young and middle-aged CAD patients who received DES were divided into MACE group (n＝57) and non MACE group (n＝321) according to whether MACE occurred during the follow-up period. Clinical data including age, gender etc. were compared between the two groups, and the variables with significant differences between the two groups were substituted into Logistic regression model to screen the influencing factors of MACE after DES implantation in young and middle-aged CAD patients. Value of influencing factors predicting occurrence of MACE after DES implantation in young and middle-aged CAD patients was evaluated by plotting ROC curve and calculating the area under the curve (AUC). ResultsStent diameter in MACE group was significantly smaller than that in non MACE group (P＜0.001), the number of left main coronary artery lesion in MACE group was significantly higher than that in non MACE group (P＜0.05). Multivariate Logistic regression analysis indicated that stent diameter (OR＝0.4,5%CI:0.084～0.405, P＜0.001) and left main coronary artery lesion (OR＝9.9,5%CI:2.291～37.904, P＝0.002) were the independent risk factors of MACE after DES implantation in young and middle-aged CAD patients. The risk of MACE after DES implantation in young and middle-aged CAD patients significantly decreased when the stent diameter was ＞3 mm. The AUC of stent diameter combined with left main coronary artery lesion predicting occurrence of MACE after DES implantation in young and middle-aged CAD patients was 0.700 (95%CI:0.623～0.776). Conclusion The smaller stent diameter and left main coronary artery lesion are the influencing factors of the occurrence of MACE after DES implantation in young and middle-aged patients with CAD, and should be emphasized by clinical practitioners.

Abstract:Aim To investigate the effect of dietary iron intake on all-cause and cardiovascular mortality in diabetic patients. Methods A total of 5 970 diabetic patients who participated in the national health and nutrition examination survey (NHANES) database of America were included. Baseline data were obtained from the questionnaire and physical examination, and the survival status and cause of death were confirmed according to the national mortality index (until December 1,5). Cox proportional survival analysis was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for iron intake and all-cause and cardiovascular mortality. Restricted cubic spline analysis was used to explore the existence of nonlinear relationship. Results The mean age of the enrolled subjects was 61.3 years old, 51.3% of whom were male, and their mean dietary iron intake was 14.11 mg per day. During a mean follow-up of 6.3 years, a total of 1 497 deaths occurred. Daily dietary iron intake ＜8.34 mg was set as control group. Compared with control group, the risk of all-cause mortality was the lowest in diabetic patients with dietary iron intake between 11.11 and 14.36 mg (HR 0.83 (0.70～0.99), P＜0.05). Restricted cubic spline regression showed that dietary iron intake was nonlinearly associated with all-cause mortality. However, there was no significant association between dietary iron intake and cardiovascular mortality. Conclusion Dietary iron intake is “L-shaped” associated with the all-cause mortality in diabetic patients, and an appropriate increase of iron intake may decrease the all-cause mortality.

Abstract:Aim To explore the association between insomnia and myocardial infarction (MI) using bidirectional two-sample Mendelian randomization (MR). Methods The summary statistics of MI were obtained from genome-wide association studies (GWAS), and single nucleotide polymorphisms (SNP) associated with insomnia phenotype were selected as instrumental variables. Inverse variance weighting (IVW) was used to evaluate the causal relationship between insomnia and MI. Results MR analysis showed that there was positive relationship between insomnia and MI (IVW:OR=1.5,5%CI 1.004～1.027, P＝0.007). There was no horizontal pleiotropy and heterogeneity in instrumental variables. Sensitivity analysis suggested that MR analysis results were stable. Reverse MR analysis showed no causal relationship between MI and increased risk of insomnia (IVW:OR=0.5,5%CI 0.466～1.126, P＝0.152), and the statistical results were stable after the removal of outliers. Conclusion Insomnia is a risk factor for MI and there was positive relationship between insomnia and MI. However, there was no causal relationship between MI and an increased risk of insomnia.

Abstract:Aim To establish an efficient and stable isolation method of primary mouse brain vascular smooth muscle cells and endothelial cells, and provide experimental materials for the investigation of pathogenesis and treatment of brain vascular diseases. Methods Brain vascular smooth muscle cells were isolated by dextran gradient centrifugation with enzymatic digestion, and endothelial cells were isolated by immunomagnetic beads sorting. Morphology and growth characteristics of two types of cells were observed with an inverted phase contrast microscope, their purity were identified by immunofluorescence, and their proliferation characteristics were observed by CCK-8 assay. At the level of cellular function, angiogenic capacity of endothelial cell was assessed by angiogenesis assay and smooth muscle cell responsiveness to platelet-derived growth factor (PDGF) was assessed by migration assay. Results The two types of cells isolated using this method grew vigorously and were in good condition. Smooth muscle cells exhibited typical “peak valley” growth, and immunofluorescence results showed cytoplasmic specific smooth muscle α-SMA and SM22α expression was positive. Endothelial cells exhibited typical “cobblestone like” growth, with positive expression of platelet endothelial cell adhesion molecule CD31 and atresia zone protein 1. Conclusion This study established a reliable and efficient method for simultaneously isolating two types of cerebrovascular cells, the isolated cells have high purity, good activity, and stable characteristics after passage, which were sufficient to meet the needs of subsequent experiments.

Abstract:Proprotein convertase subtilisin/kexin type 9 (PCSK9) comprised of 692 amino acids is the ninth member of protease family. It binds to the low-density lipoprotein receptor(LDLR), leading to elevated levels of circulating low-density lipoprotein cholesterol(LDLC), which can lead to a number of cardiovascular diseases, and among then the relationship with cardiovascular calcification has recently received attention. Cardiovascular calcification is a kind of ectopic mineralisation in the cardiovascular system, which is mainly characterised by the production of mineral deposits in the vascular wall and vascular valves, and its pathogenesis is related to lipoprotein content, platelet activity, matrix vesicle (MV) release and inflammation, through which PCSK9 may be involved in the occurrence of cardiovascular calcification.Therefore, this article reviews the relationship between PCSK9 and cardiovascular calcification, emphasizing the specific role of PCSK9 in affecting cardiovascular calcification through various pathways, assisting in setting up emerging applications of PCSK9 amid vessel biological science and recognize innovative molecular mechanisms for its treatment.

Abstract:In-stent restenosis(ISR) is a significant cause of long-term prognosis after percutaneous coronary intervention (PCI). The inflammatory response is a critical factor in its development. Unlike the chronic inflammatory process of traditional atherosclerosis, ISR may develop acute coronary events within even months or years, and the inflammatory mechanisms of ISR are more complex. Inflammatory factors regulate various mechanisms, including monocyte macrophage proliferation, endothelial cell damage and repair, foam cell formation, and smooth muscle cell proliferation and migration after PCI. The review briefly describes the classification and risk factors of ISR. It emphasizes the role of various inflammatory factors in ISR to provide new ideas for investigating the inflammatory mechanism of ISR and clinical intervention.

Abstract:Diabetes cardiomyopathy (DCM) is a cardiovascular disease with structural damage and dysfunction of myocardium under the condition of glucose and lipid metabolism disorder in diabetes. The main pathological characteristics are ventricular hypertrophy, myocardial remodeling and cardiomyocyte death, which induce heart failure. DCM has become one of the main causes of death in patients with diabetes. As a pro-inflammatory programmed cell death pathway, pyroptosis mediated by inflammasomes is considered an important driver of chronic inflammation due to its excessive activation. Recently, it was found that the over activation of pyroptosis promoted the course of DCM and became the hub connecting the disorder of glucose and lipid metabolism in diabetes and myocardial injury. With the discovery of more and more roles of Traditional Chinese Medicine (TCM) in regulating pyroptosis, TCM affects the occurrence and development of DCM by regulating pyroptosis or protein expression, which has become a research hotspot of myocardial protection strategies in diabetes. This article reviews the mechanism of pyroptosis in DCM and the research progress of TCM monomers and compound prescriptions in regulating the process of pyroptosis in DCM, in order to provide new ideas and targets for clinical research and treatment of DCM.

Abstract:Atherosclerosis (As) is one of the major causes of high mortality and morbidity worldwide. Chemokines and their receptors are involved in the pathogenesis of As. CXC chemokine ligand 12 (CXCL12) is a member of the chemokine family, and macrophage migration inhibition factor (MIF) is a chemokine like functional chemokine, CXCL12 and MIF together play important roles in As through CXC chemokine receptor 4 (CXCR4). The CXCL12-CXCR4 bioaxis is an important chemokine/chemokine receptor axis that can regulate various biological behaviors such as cell proliferation, mobilization, differentiation, homing, and chemotaxis. Numerous studies have found that it widely affects various cells related to As and is closely related to the formation and development of As plaques. Therefore, the CXCL12/MIF-CXCR4 bioaxis is expected to become a more precise target for As treatment, and regulating the CXCL12/MIF-CXCR4 bioaxis strategy provides new ideas for the prevention and treatment of As.