KLF4 inhibited the senescence-associated secretory phenotype in ox-LDL-treated endothelial cells via PDGFRA/NAMPT/mitochondrial ROS.

BACKGROUND: Inflammation is one of the significant consequences of ox-LDL-induced endothelial cell (EC) dysfunction. The senescence-associated secretory phenotype (SASP) is a critical source of inflammation factors. However, the molecular mechanism by which the SASP is regulated in ECs under ox-LDL conditions remains unknown. RESULTS: The level of SASP was increased in ox-LDL-treated ECs, which could be augmented by KLF4 knockdown whereas restored by KLF4 knock-in. Furthermore, we found that KLF4 directly promoted PDGFRA transcription and confirmed the central role of the NAPMT/mitochondrial ROS pathway in KLF4/PDGFRA-mediated inhibition of SASP. Animal experiments showed a higher SASP HFD-fed mice, compared with normal feed (ND)-fed mice, and the endothelium of EC-specific KLF4-/- mice exhibited a higher proportion of SA-ß-gal-positive cells and lower PDGFRA/NAMPT expression. CONCLUSIONS: Our results revealed that KLF4 inhibits the SASP of endothelial cells under ox-LDL conditions through the PDGFRA/NAMPT/mitochondrial ROS. METHODS: Ox-LDL-treated ECs and HFD-fed mice were used as endothelial senescence models in vitro and in vivo. SA-ß-gal stain, detection of SAHF and the expression of inflammatory factors determined SASP and senescence of ECs. The direct interaction of KLF4 and PDGFRA promotor was analyzed by EMSA and fluorescent dual luciferase reporting analysis.

The relationship between glycemic risk and longitudinal changes in total physiological atherosclerotic burden in patients with coronary artery disease.

Background: The effects of glycemic status on coronary physiology have not been well evaluated. This study aimed to investigate changes in coronary physiology by using angiographic quantitative flow ratio (QFR), and their relationships with diabetes mellitus (DM) and glycemic control status. Methods: This retrospective cohort study included 530 patients who underwent serial coronary angiography (CAG) measurements between January 2016 and December 2021 at Tongji Hospital of Tongji University. Based on baseline and follow-up angiograms, 3-vessel QFR (3V-QFR) measurements were performed. Functional progression of coronary artery disease (CAD) was defined as a change in 3V-QFR (Δ3V-QFR = 3V-QFRfollow-up - 3V-QFRbaseline) ≤-0.05. Univariable and multivariable logistic regression analyses were applied to identify the independent predictors of coronary functional progression. Subgroup analysis according to diabetic status was performed. Results: During a median interval of 12.1 (10.6, 14.3) months between the two QFR measurements, functional progression was observed in 169 (31.9%) patients. Follow-up glycosylated hemoglobin (HbA1c) was predictive of coronary functional progression with an area under the curve (AUC) of 0.599 [95% confidence interval (CI): 0.546-0.651; P<0.001] in the entire population. Additionally, the Δ3V-QFR values were significantly lower in diabetic patients with HbA1c ≥7.0% compared to those with well-controlled HbA1c or non-diabetic patients [-0.03 (-0.09, 0) vs. -0.02 (-0.05, 0.01) vs. -0.02 (-0.05, 0.02); P=0.002]. In a fully adjusted multivariable logistics analysis, higher follow-up HbA1c levels were independently associated with progression in 3V-QFR [odds ratio (OR), 1.263; 95% CI: 1.078-1.479; P=0.004]. Furthermore, this association was particularly strong in diabetic patients (OR, 1.353; 95% CI: 1.082-1.693; P=0.008) compared to patients without DM. Conclusions: Among patients with established CAD, on-treatment HbA1c levels were independently associated with progression in physiological atherosclerotic burden, especially in patients with DM.

Impact of percutaneous coronary intervention on renal function in patients with coronary heart disease.

The relationship between cardiac and renal function is complicated. The impact of percutaneous coronary intervention (PCI) on renal function in patients with coronary artery disease is still unclear. The current study sought to assess renal function change, including the time course of renal function, after elective PCI in patients with improved renal function and to identify renal function predictors of major adverse cardiovascular events. We examined data from 1572 CHD patients who had coronary angiography (CAG) or PCI in this retrospective cohort study. Patients receiving elective PCI (n=1240) and CAG (n=332) between January 2013 and December 2018 were included. Pre-PCI and procedural variables associated with post-PCI eGFR, change in renal function after post-PCI follow-up, and post-PCI eGFR association with major adverse cardiovascular events were investigated. Following the procedure, 88.7 percent of PCI group patients had unchanged or improved renal function. The treatment of PCI was found to independently correlate with IRF following coronary angiography in an analysis of patients undergoing PCI [OR 4.561 (95% CI:2 .556-8.139); p<0.001]. The area under the receiver operating characteristic (ROC) curve is 0.763 (model with the treatment of PCI). Improved renal function (IRF) and stable renal function were both associated with a lower risk of a major cardiovascular event.

Exploration of the Crucial Genes and Molecular Mechanisms Mediating Atherosclerosis and Abnormal Endothelial Shear Stress.

Background: Abnormal endothelial shear stress (ESS) is a significant risk factor for atherosclerosis (AS); however, the genes and pathways between ESS and AS are poorly understood. Here, we screened hub genes and potential regulatory targets linked to the progression of AS induced by abnormal ESS. Methods: The microarray data of ESS and AS were downloaded from the Gene Expression Omnibus (GEO) database. The coexpression modules related to shear stress and AS were identified with weighted gene coexpression network analysis (WGCNA). Coexpression genes in modules obtained from GSE28829 and GSE160611 were considered as SET1. The results were validated in validation set by differential gene analysis. The limma package in R was used to identify differentially expressed genes (DEGs). The common DEGs of GSE100927 and GSE103672 were regarded as SET2. Next, Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was conducted. Protein-protein interaction (PPI) enrichment analysis was assembled, and hub genes were identified using MCODE and ClueGO in Cytoscape. ROC curve analyses were conducted to assess the ability of common hub genes to distinguish samples of atherosclerotic plaque from normal arterial. The expression of common hub gene was verified in ox-LDL-induced foam cells and GSE41571. Results: We identified three gene modules (the blue, tan, and cyan modules) related to AS and three shear stress-related modules (the brown, red, and pink modules). A total of 129 genes in SET1 and 476 genes in SET2 were identified. CCRL2, LGALS9, and PLCB2 were identified as common hub genes and validated in the GSE100927, GSE28829, and GSE41571. ROC analysis indicates the expression of CCRL2, LGALS9, and PLCB2 could effectively distinguish the atherosclerotic plaque and normal arterial. The expression level of CCRL2, LGALS9, and PLCB2 increases with the accumulation of lipid increased. Conclusion: We identified CCRL2, LGALS9, and PLCB2 as key genes associated with abnormal ESS and AS and may provide potential prevention and treatment target of AS induced by abnormal ESS.

Mechanism of homocysteine-mediated endothelial injury and its consequences for atherosclerosis.

Homocysteine (Hcy) is an intermediate amino acid formed during the conversion from methionine to cysteine. When the fasting plasma Hcy level is higher than 15 µmol/L, it is considered as hyperhomocysteinemia (HHcy). The vascular endothelium is an important barrier to vascular homeostasis, and its impairment is the initiation of atherosclerosis (AS). HHcy is an important risk factor for AS, which can promote the development of AS and the occurrence of cardiovascular events, and Hcy damage to the endothelium is considered to play a very important role. However, the mechanism by which Hcy damages the endothelium is still not fully understood. This review summarizes the mechanism of Hcy-induced endothelial injury and the treatment methods to alleviate the Hcy induced endothelial dysfunction, in order to provide new thoughts for the diagnosis and treatment of Hcy-induced endothelial injury and subsequent AS-related diseases.

Pioglitazone alleviates inflammation in diabetic mice fed a high-fat diet via inhibiting advanced glycation end-product-induced classical macrophage activation.

Classically activated macrophages (M1) are associated with inflammation in diabetic patients. Inflammation is a known risk factor in diabetes. The present study tested the hypothesis that pioglitazone (PIO) alleviates inflammation in diabetic mice fed a high-fat diet by inhibiting advanced glycation end-product (AGE)-induced classical macrophage activation. It was found that AGE treatment promoted the transcription of pro-inflammatory molecules and M1 surface markers, whereas PIO increased the expression of anti-inflammatory genes and decreased the expression of pro-inflammatory mediators in bone marrow-derived macrophages (BMDMs) in a dose-dependent manner. Furthermore, pretreatment with PIO abrogated the effects of AGE on pro-inflammatory markers and partly inhibited AGE-induced nuclear factor-κB (NF-κB) activation. PIO treatment partly reduced the inflammatory phenotype in diabetic ApoE(-/-) mice, and significantly reduced NF-κB activation in plaques. Therefore, we conclude that PIO blocks classical activation of macrophages and attenuates inflammation in mouse models of diabetes.

Effect of the angiotensin II receptor blocker valsartan on cardiac hypertrophy and myocardial histone deacetylase expression in rats with aortic constriction.

The aim of the present study was to observe the myocardial expression of members of the histone deacetylase (HDAC) family (HDAC2, HDAC5 and HDAC9) in rats with or without myocardial hypertrophy (MH) in the presence and absence of the angiotensin II receptor blocker valsartan. Adult male Wistar rats were randomly divided into three groups (n=6/group): Sham-operated control rats, treated with distilled water (1 ml/day) through gavage; rats with MH (established through aortic constriction), treated with distilled water (1 ml/day) through gavage; and MH + valsartan rats, treated with 20 mg/kg/day valsartan through gavage. Treatments commenced one day after surgery and continued for eight weeks. Body weight (BW), heart weight (HW) and plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels were determined, and the myocardial expression of HDAC2, HDAC5 and HDAC9 was analyzed through a reverse transcription semi-quantitative polymerase chain reaction. The BWs of the rats in the three groups were similar at baseline; however, after eight weeks the BW of the rats in the MH + valsartan group was significantly reduced compared with that of the MH rats. Furthermore, the HW/BW ratio and plasma ANP and BNP levels were increased, the myocardial HDAC2 expression was significantly upregulated and the HDAC5 and HDAC9 expression was significantly downregulated in the MH rats compared with those in the control rats; however, these changes were significantly attenuated by valsartan. Modulation of myocardial HDAC5, HDAC9 and HDAC2 expression may therefore be one of the anti-hypertrophic mechanisms of valsartan in this rat MH model.

Advanced Glycation End Products Enhance Macrophages Polarization into M1 Phenotype through Activating RAGE/NF-κB Pathway.

Atherosclerotic lesions are accelerated in patients with diabetes. M1 (classically activated in contrast to M2 alternatively activated) macrophages play key roles in the progression of atherosclerosis. Since advanced glycation end products (AGEs) are major pathogenic factors and active inflammation inducers in diabetes mellitus, this study assessed the effects of AGEs on macrophage polarization. The present study showed that AGEs significantly promoted macrophages to express IL-6 and TNF-α. M1 macrophage markers such as iNOS and surface markers including CD11c and CD86 were significantly upregulated while M2 macrophage markers such as Arg1 and CD206 remained unchanged after AGEs stimulation. AGEs significantly increased RAGE expression in macrophages and activated NF-κB pathway, and the aforementioned effects were partly abolished by administration of anti-RAGE antibody or NF-κB inhibitor PDTC. In conclusion, our results suggest that AGEs enhance macrophage differentiation into proinflammatory M1 phenotype at least partly via RAGE/NF-κB pathway activation.

Role of CD11b+Gr-1+ myeloid cells in AGEs-induced myocardial injury in a mice model of acute myocardial infarction.

AIMS: Polymorph neutrophils are the predominant inflammatory cells and play a crucial role on the pathogenesis of myocardial injury at the early stage of acute myocardial infarction (AMI). However, the precursors and the differentiation of neutrophils are not fully understood. Here we explored the role of CD11b+Gr-1+ myeloid-derived suppressor cells (MDSCs) on myocardial injury in the absence and presence of advanced glycation end-products (AGEs) in a mice model of AMI. METHODS AND RESULTS: Male C57BL/6J mice were selected. Fluorescent actived cell sortor (FACS) data demonstrated significantly increased CD11b+Gr-1+ MDSCs both in peripheral blood circulation and in the ischemic myocardium at 24 hours post AMI. Quantitative-real-time PCR results also revealed significantly upregulated CD11b and Ly6G mRNA expression in the ischemic myocardium. AGEs treatment further aggravated these changes in AMI mice but not in sham mice. Moreover, AGEs treatment also significantly increased infarction size and enhanced cardiomyocyte apoptosis. The mRNA expression of pro-inflammatory cytokine IL-6 and iNOS2 was also significantly increased in AMI + AGEs group compared to AMI group. CONCLUSION: These data suggest enhanced infiltration of MDSCs by AGEs contributes to aggravated myocardial injury in AMI mice, which might be one of the mechanisms responsible for severer myocardial injury in AMI patients complicating diabetes.