Activating transcription factor 3 is a potential target and a new biomarker for the prognosis of atherosclerosis

TFTG: A comprehensive database for human transcription factors and their targets

Transcription factors (TFs) are major contributors to gene transcription, especially in controlling cell-specific gene expression and disease occurrence and development. Uncovering the relationship between TFs and their target genes is critical to understanding the mechanism of action of TFs. With the development of high-throughput sequencing techniques, a large amount of TF-related data has accumulated, which can be used to identify their target genes. In this study, we developed TFTG (Transcription Factor and Target Genes) database (http://tf.liclab.net/TFTG), which aimed to provide a large number of available human TF-target gene resources by multiple strategies, besides performing a comprehensive functional and epigenetic annotations and regulatory analyses of TFs. We identified extensive available TF-target genes by collecting and processing TF-associated ChIP-seq datasets, perturbation RNA-seq datasets and motifs. We also obtained experimentally confirmed relationships between TF and target genes from available resources. Overall, the target genes of TFs were obtained through integrating the relevant data of various TFs as well as fourteen identification strategies. Meanwhile, TFTG was embedded with user-friendly search, analysis, browsing, downloading and visualization functions. TFTG is designed to be a convenient resource for exploring human TF-target gene regulations, which will be useful for most users in the TF and gene expression regulation research.

GATA2‑miR‑374a axis promotes vascular smooth muscle cells proliferation, migration via targeting circTADA2A/RORA axis

Evidence has shown that microRNAs (miRNAs/miRs) play key roles in biological functions of vascular smooth muscle cells (VSMCs). However, the role of miR-374a in VSMCs remains to be elucidated. The present study aimed to explore the influence of miR-374a on VSMCs and its molecular mechanism. The expression level of miR-374a was measured by reverse transcription-quantitative (RT-q) PCR. MTT and Transwell assay were employed to assess the role of miR-374a in proliferation and migration of VSMCs. To order to determine miR-374a targets, a dual-luciferase reporter assay was conducted, which was further verified by rescue experiments. Chromatin Immunoprecipitation Assay and JASPAR databases were applied to explore the regulatory association between GATA binding protein 2 (GATA2) and miR-374a. Western blotting or RT-qPCR were employed to detect the protein expression levels of GATA2 or RAR-related orphan receptor A (RORA). The present study found that miR-374a was elevated in VSMCs following treatment with platelet-derived growth factor-BB (PDGF-BB) compared with that in control group. In addition, the results demonstrated that a higher expression of a miR-374a could promote proliferation and migration of VSMCs while miR-374a inhibitor suppressed the PDGF-BB-induced proliferation and migration of VSMCs in vitro. Furthermore, circTADA2A bound to miR-374a and then upregulated RORA expression, which resulted in inhibition in VSMCs proliferation and migration. On the other hand, the result indicated that GATA2 overexpression could augment the proliferation, migration of PDGF-bb-induced VSMCs, which could be rescued by miR-374a inhibitor. The findings suggested that the GATA2/circTADA2A-miR-374a axis promoted the proliferation and migration of VSMCs by targeting RORA, which were closely related to atherosclerosis (AS). Thus the results might offer a new therapeutic target for AS.

Emerging regulatory mechanisms in cardiovascular disease: Ferroptosis

Ferroptosis, distinct from apoptosis, necrosis, autophagy, and other types of cell death, is a novel iron-dependent regulated cell death characterized by the accumulation of lipid peroxides and redox imbalance with distinct morphological, biochemical, and genetic features. Dysregulation of iron homeostasis, the disruption of antioxidative stress pathways and lipid peroxidation are crucial in ferroptosis. Ferroptosis is involved in the pathogenesis of several cardiovascular diseases, including atherosclerosis, cardiomyopathy, myocardial infarction, ischemia-reperfusion injury, abdominal aortic aneurysm, aortic dissection, and heart failure. Therefore, a comprehensive understanding of the mechanisms that regulate ferroptosis in cardiovascular diseases will enhance the prevention and treatment of these diseases. This review discusses the latest findings on the molecular mechanisms of ferroptosis and its regulation in cardiovascular diseases, the application of ferroptosis modulators in cardiovascular diseases, and the role of traditional Chinese medicines in ferroptosis regulation to provide a comprehensive understanding of the pathogenesis of cardiovascular diseases and identify new prevention and treatment options.

Identification of potential hub genes and regulatory networks of smoking-related endothelial dysfunction in atherosclerosis using bioinformatics analysis

BACKGROUND

Endothelial dysfunction, the earliest stage of atherosclerosis, can be caused by smoking, but its molecular mechanism requires further investigation.

OBJECTIVE

This study aimed to use bioinformatics analysis to identify potential mechanisms involved in smoking-related atherosclerotic endothelial dysfunction.

METHODS

The transcriptome data used for this bioinformatics analysis were obtained from the Gene Expression Omnibus (GEO) database. The GSE137578 and GSE141136 datasets were used to identify common differentially expressed genes (co-DEGs) in endothelial cells treated with oxidized low-density lipoprotein (ox-LDL) and tobacco. The co-DEGs were annotated using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomics (KEGG) databases. Additionally, a protein-protein interaction (PPI) network was constructed to visualize their interactions and screen for hub genes. GSE120521 dataset was used to verify the expression of hub genes in unstable plaques. The miRNA expression profile GSE137580 and online databases (starBase 2.0, TargetScan 8.0 and DGIdb v4.2.0) were used to predict the related non-coding RNAs and drugs.

RESULTS

A total of 232 co-DEGs were identified, including 113 up-regulated genes and 119 down-regulated genes. These DEGs were primarily enriched in detrimental autophagy, cell death, transcription factors, and cytokines, and were implicated in ferroptosis, abnormal lipid metabolism, inflammation, and oxidative stress pathways. Ten hub genes were screened from the constructed PPI network, including up-regulated genes such as FOS, HMOX1, SQSTM1, PTGS2, ATF3, DDIT3, and down-regulated genes MCM4, KIF15, UHRF1, and CCL2. Importantly, HMOX1 was further up-regulated in unstable plaques (p= 0.034). Finally, a regulatory network involving lncRNA/circRNA-miRNA-hub genes and drug-hub genes was established.

CONCLUSION

Atherosclerotic endothelial dysfunction is associated with smoking-induced injury. Through bioinformatics analysis, we identified potential mechanisms and provided potential therapeutic targets.

Research progress on activation transcription factor 3: A promising cardioprotective molecule

Activation transcription factor 3 (ATF3), a member of the ATF/cyclic adenosine monophosphate response element binding family, can be induced by a variety of stresses. Numerous studies have indicated that ATF3 plays multiple roles in the development and progression of cardiovascular diseases, including atherosclerosis, hypertrophy, fibrosis, myocardial ischemia-reperfusion, cardiomyopathy, and other cardiac dysfunctions. In past decades, ATF3 has been demonstrated to be detrimental to some cardiac diseases. Current studies have indicated that ATF3 can function as a cardioprotective molecule in antioxidative stress, lipid metabolic metabolism, energy metabolic regulation, and cell death modulation. To unveil the potential therapeutic role of ATF3 in cardiovascular diseases, we organized this review to explore the protective effects and mechanisms of ATF3 on cardiac dysfunction, which might provide rational evidence for the prevention and cure of cardiovascular diseases.

ATF3 in atherosclerosis: a controversial transcription factor

Atherosclerosis, the pathophysiological basis of most malignant cardiovascular diseases, remains a global concern. Transcription factors play a key role in regulating cell function and disease progression in developmental signaling pathways involved in atherosclerosis. Activated transcription factor (ATF) 3 is an adaptive response gene in the ATF/cAMP response element binding (CREB) protein family that acts as a transcription suppressor or activator by forming homodimers or heterodimers with other ATF/CREB members. Appropriate ATF3 expression is vital for normal physiological cell function. Notably, ATF3 exhibits distinct roles in vascular endothelial cells, macrophages, and the liver, which will also be described in detail. This review provides a new perspective for atherosclerosis therapy by summarizing the mechanism of ATF3 in atherosclerosis, as well as the structure and pathophysiological properties of ATF3. KEY MESSAGES: • In endothelial cells, ATF3 overexpression aggravates oxidative stress and inflammation. • In macrophages and liver cells, ATF3 can act as a negative regulator of inflammation and promote cholesterol metabolism. • ATF3 can be used as a potential therapeutic factor in the treatment of atherosclerosis.

Protective role of activating transcription factor 3 against neuronal damage in rats with cerebral ischemia

BACKGROUND

The participation of activating transcription factor 3 (ATF3) in transient middle cerebral artery occlusion and reperfusion injury has been reported. However, the precise mechanism of ATF3 in cerebral ischemia is little known so far. Thus, the study examines the mechanism of action underlying the protective role of ATF3 following middle cerebral artery occlusion (MCAO) in rats.

METHODS AND RESULTS

The MCAO rats exhibited reduced body weight and motor ability, while increased neurological deficits and brain infarct volume. Gene ontology (GO) enrichment and KEGG pathway analyses revealed that differentially expressed genes were mainly enriched in the TLR4/NF-κB signaling. Moreover, ATF3 was the most differentially expressed gene in brain tissues of MCAO rats versus sham-operated rats, which could bind to CCL2. ATF3 was reduced in MCAO rats, and ATF3 inhibited CCL2 expression to mediate the TLR4/NF-κB signaling. Functionally, ATF3 inhibited neuronal apoptosis, microglia activation, and pro-inflammatory cytokine production to alleviate brain injury in rats. By contrast, CCL2 was overexpressed in neurons and microglia, and CCL2 mitigated the effects of ATF3 to exacerbate brain injury in rats.

CONCLUSION

Our findings suggested that ATF3 repressed neuronal apoptosis and microglia activation caused by cerebral ischemia via targeting CCL2 and mediating the TLR4/NF-κB signaling.

Small, Dense Low-Density Lipoprotein-Cholesterol and Atherosclerosis: Relationship and Therapeutic Strategies

Low-density lipoprotein cholesterol (LDL-C) plays an important role in the formation, incidence, and development of atherosclerosis (AS). Low-density lipoproteins can be divided into two categories: large and light LDL-C and small, dense low-density lipoprotein cholesterol (sdLDL-C). In recent years, an increasing number of studies have shown that sdLDL-C has a strong ability to cause AS because of its unique characteristics, such as having small-sized particles and low density. Therefore, this has become the focus of further research. However, the specific mechanisms regarding the involvement of sdLDL-C in AS have not been fully explained. This paper reviews the possible mechanisms of sdLDL-C in AS by reviewing relevant literature in recent years. It was found that sdLDL-C can increase the atherogenic effect by regulating the activity of gene networks, monocytes, and enzymes. This article also reviews the research progress on the effects of sdLDL-C on endothelial function, lipid metabolism, and inflammation; it also discusses its intervention effect. Diet, exercise, and other non-drug interventions can improve sdLDL-C levels. Further, drug interventions such as statins, fibrates, ezetimibe, and niacin have also been found to improve sdLDL-C levels.

TCM Regulates PI3K/Akt Signal Pathway to Intervene Atherosclerotic Cardiovascular Disease

Vascular endothelial injury is the initial stage of atherosclerosis (AS). Stimulating and activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway can regulate the expression of vascular endothelial cytokines, thus affecting the occurrence and development of AS. In addition, the PI3K/Akt signaling pathway can regulate the polarization and survival of macrophages and the expression of inflammatory factors and platelet function, thus influencing the progression of AS. In recent years, traditional Chinese medicine (TCM) has been widely recognized for its advantages of fewer side effects, multiple pathways, and multiple targets. Also, the research of TCM regulation of AS via the PI3K/Akt signaling pathway has achieved certain results. This study aimed to analyze the characteristics of the PI3K/Akt signaling pathway and its role in the pathogenesis of AS, as well as the role of Chinese medicine in regulating the PI3K/Akt signaling pathway. The findings are expected to provide a theoretical basis for the clinical treatment and pathological mechanism research of AS.

Ferroptosis: the potential value target in atherosclerosis

In advanced atherosclerosis (AS), defective function-induced cell death leads to the formation of the characteristic necrotic core and vulnerable plaque. The forms and mechanisms of cell death in AS have recently been elucidated. Among them, ferroptosis, an iron-dependent form of necrosis that is characterized by oxidative damage to phospholipids, promotes AS by accelerating endothelial dysfunction in lipid peroxidation. Moreover, disordered intracellular iron causes damage to macrophages, vascular smooth muscle cells (VSMCs), vascular endothelial cells (VECs), and affects many risk factors or pathologic processes of AS such as disturbances in lipid peroxidation, oxidative stress, inflammation, and dyslipidemia. However, the mechanisms through which ferroptosis initiates the development and progression of AS have not been established. This review explains the possible correlations between AS and ferroptosis, and provides a reliable theoretical basis for future studies on its mechanism.

Research on the correlation between activating transcription factor 3 expression in the human coronary artery and atherosclerotic plaque stability

Background

Activating transcription factor 3 (ATF3) is an early response gene that is activated in response to atherosclerotic stimulation and may be an important factor in inhibiting the progression of atherosclerosis. In this study, we directly measured the expression of ATF3 and inflammatory factors in human coronary atherosclerotic plaques to examine the relationship between ATF3 expression, inflammation and structural stability in human coronary atherosclerotic plaques.

Methods

A total of 68 coronary artery specimens were collected from the autopsy group, including 36 cases of sudden death from coronary heart disease (SCD group) and 32 cases of acute death caused by mechanical injury with coronary atherosclerosis (CHD group). Twenty-two patients who had no coronary heart disease were collected as the control group (Con group). The histological structure of the coronary artery was observed under a light microscope after routine HE staining, and the intimal and lesion thicknesses, thickness of the fibrous cap, thickness of necrosis core, degree of lumen stenosis were assessed by image analysis software. Western blotting and immunohistochemistry were used to measure the expression and distribution of ATF3, inflammatory factors (CD45, IL-1β, TNF-α) and matrix metalloproteinase-9 (MMP-9) and vascular cell adhesion molecule 1 (VCAM1) in the coronary artery. The Pearson correlation coefficient was used to analyse the correlation between ATF3 protein expression and inflammatory factors and between ATF3 protein expression and structure-related indexes in the lesion group.

Results

Compared with those in the control group, the intima and necrotic core in the coronary artery were thickened, the fibrous cap became thin and the degree of vascular stenosis was increased in the lesion group, while the intima and necrotic core became thicker and the fibrous cap became thinner in the SCD group than in the CHD group (P < 0.05). There was no or low expression of ATF3, inflammatory factors, VCAM1 and MMP-9 in the control group, and the expression of inflammatory factors, VCAM1 and MMP-9 in the SCD group was higher than that in CHD group, while the expression of ATF3 in the SCD group was significantly lower than that in CHD group (P < 0.05). In the lesion group, the expression of ATF3 was negatively correlated with intimal and necrotic focus thickness, positively correlated with fibrous cap thickness (P < 0.01), and negatively correlated with inflammatory factors, VCAM1 and MMP-9 (P < 0.01).

Conclusions

The expression of ATF3 may be related to the progression and stability of atherosclerotic plaques, and may affect the structural stability of atherosclerotic plaques by regulating the inflammatory response, thus participating in the regulation of atherosclerotic progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02161-9.