Oviductal Glycoprotein 1 Promotes Hypertension by Inducing Vascular Remodeling Through an Interaction With MYH9

A comprehensive review on selenium and blood pressure: Recent advances and research perspectives

BACKGROUND

Globally, approximately 31.1 % of adults are affected by hypertension(HTN), and there is currently no effective treatment for this condition. Selenium (Se), an essential trace element in the human body, has been shown to play a role in various biological processes, including anti-inflammation, antioxidative stress, anti-ferroptosis, and regulation of immune response. Research suggests that Se may have potential hypotensive effects.

OBJECTIVE

This review aims to comprehensively investigate the relationship between Se and blood pressure(BP), elucidate the mechanisms through which Se influences BP, and explore its prospective applications in clinical practice.

METHODS

We conducted a systematic search on PubMed for a thorough review of articles concerning the relationship between Se and BP, as well as the mechanisms by which Se may lower BP.

RESULTS AND CONCLUSIONS

Although some findings indicate that Se might increase BP, its anti-inflammatory, anti-oxidant, anti-vascular remodeling, anti-atherosclerotic, anti-ferroptosis, and regulation of immune response effects suggest that maintaining an appropriate level of Se may contribute to BP reduction and possibly lower the risk of pregnancy-induced hypertension(PIH). While Se shows promise in the management of HTN, further exploration is necessary for its development. Future studies should clarify the mechanisms involved and identify relevant targets through clinical research, which may provide adjunctive therapies for HTN.

Endothelial FOSL1 drives angiotensin II-induced myocardial injury via AT1R-upregulated MYH9

Vascular remodeling represents a pathological basis for myocardial pathologies, including myocardial hypertrophy and myocardial infarction, which can ultimately lead to heart failure. The molecular mechanism of angiotensin II (Ang II)-induced vascular remodeling following myocardial infarction reperfusion is complex and not yet fully understood. In this study, we examined the effect of Ang II infusion on cardiac vascular remodeling in mice. Single-cell sequencing showed Ang II induced cytoskeletal pathway enrichment and that FOS like-1 (FOSL1) affected mouse cardiac endothelial dysfunction by pseudotime analysis. Myosin heavy chain 9 (MYH9) was predominantly expressed in primary cardiac endothelial cells. The Ang II type I receptor blocker telmisartan and the protein kinase C inhibitor staurosporine suppressed Ang II-induced upregulation of MYH9 and FOSL1 phosphorylation in human umbilical vein endothelial cells. Silencing MYH9 abolished Ang II-mediated inhibition of angiogenesis in human umbilical vein endothelial cells, and attenuated AngII-induced vascular hyperpermeability. We found that FOSL1 directly bound to the MYH9 promoter and thus activated transcription of MYH9 by the dual luciferase reporter and chromatin immunoprecipitation assays, leading to vascular dysfunction. In vivo, 6 weeks after injecting adeno-associated virus-ENT carrying the TEK tyrosine kinase (tie) promoter-driven short hairpin RNA for silencing FOSL1 (AAV-tie-shFOSL1), cardiac function represented by the ejection fraction and fractional shortening was improved, myocardial fibrosis was decreased, protein levels of phosphorylated FOSL1, MYH9, and collagen type I alpha were reduced, and cardiac vascular density was recovered in mice with endothelial Fosl1-specific knockdown in Ang II-infused mice. In ischemia-reperfusion mice, AAV-shFosl1 mice had a reduced infarct size and preserved cardiac function compared with control AAV mice. Our findings suggest a critical role of the FOSL1/MYH9 axis in hindering Ang II-induced vascular remodeling, and we identified FOSL1 as a potential therapeutic target in endothelial cell injuries induced by myocardial ischemia-reperfusion.

A Novel Disulfidptosis-Related Diagnostic Gene Signature and Differential Expression Validation in Ischaemic Cardiomyopathy

Ischaemic cardiomyopathy (IC) predominantly arises from prolonged deprivation of oxygen in the coronary arteries, resulting in compromised cardiac contractility or relaxation. This study investigates the role of disulfidptosis-associated genes (DiGs) in IC. Through the analysis of datasets GSE5406 and GSE57338, we explored the association between DiGs and immune characteristics to identify crucial genes contributing to IC development. The support vector machine model emerged as the most effective, identifying key genes such as MYH9, NUBPL, MYL6, MYH10 and NCKAP1. Validation with independent datasets GSE57345, GSE48166 and single-cell GSE145154 further supported these findings, demonstrating high predictive accuracy. Experimental validation in an IC mouse model, using Western blot, immunohistochemistry and RT-qPCR, confirmed the altered expression of these core genes in myocardial ischaemic regions. This research not only elucidates the significance of DiGs in IC but also underscores the diagnostic potential of identified core genes.

USP25 ameliorates vascular remodeling by deubiquitinating FOXO3 and promoting autophagic degradation of FOXO3

Long-term hypertension causes excessive vascular remodeling and leads to adverse cardiovascular events. Balance of ubiquitination and deubiquitination has been linked to several chronic conditions, including pathological vascular remodeling. In this study, we discovered that the expression of ubiquitin-specific protease 25 (USP25) is significantly up-regulated in angiotensin II (Ang II)-challenged mouse aorta. Knockout of Usp25 augments Ang II-induced vascular injury such as fibrosis and endothelial to mesenchymal transition (EndMT). Mechanistically, we found that USP25 interacts directly with Forkhead box O3 (FOXO3) and removes the K63-linked ubiquitin chain on the K258 site of FOXO3. We also showed that this USP25-mediated deubiquitination of FOXO3 increases its binding to light chain 3 beta isoform and autophagosomic-lysosomal degradation of FOXO3. In addition, we further validated the biological function of USP25 by overexpressing USP25 in the mouse aorta with AAV9 vectors. Our studies identified FOXO3 as a new substrate of USP25 and showed that USP25 may be a potential therapeutic target for excessive vascular remodeling-associated diseases.

The role of LNK in mitigating hypertension: inhibition of vascular smooth muscle proliferation and JAK-STAT pathway

The lymphocyte adaptor protein LNK is predominantly found in endothelial and hematopoietic cells and is linked to cardiovascular and autoimmune diseases. LNK functions as a negative regulator of cytokine signaling and cell proliferation, but its impact on hypertensive vascular smooth muscle cells (HVSMC) remains unclear. This study aimed to explore the influence of LNK on HVSMC function. To achieve this, vascular smooth muscle cells (VSMCs) from rat thoracic aorta were isolated and identified using immunofluorescence. A hypertensive cell model was established by treatment with angiotensin-II, confirmed through the MTT method. Lentivirus was utilized to create stable silencing and overexpression of the LNK gene. Flow cytometry assessed VSMC cycle, proliferation, and migration levels, while ELISA measured IL-6, TNF-α, and IFN-γ expression levels. Real-time quantitative PCR and western blot were employed to analyze LNK, STAT3, JAK1, JAK2, JAK3 mRNA, and protein expression in rat VSMC. Immunofluorescence results indicated that most VSMCs expressed vimentin, with a proliferation rate of 48.5% in VSMCs treated with 100 nM angiotensin-II, confirming successful isolation and model construction of HVSMC. Compared to the control group, the angiotensin-II group exhibited increased HVSMCs in S and G2/M-phases of the cell cycle, decreased in G0/G1 phases, higher proliferation and migration capacity, and elevated inflammation levels. Additionally, JAK1, JAK2, and STAT3 signaling pathway-related mRNA and protein expression were significantly elevated. These effects were further intensified by the combined action of angiotensin-II and LNK silencing virus. Conversely, these effects were notably reduced when angiotensin-II was combined with the LNK overexpressing virus. These findings suggest that LNK mitigates the impact of hypertension and inflammation by inhibiting the proliferation, migration, and JAK-STAT signaling pathway of HVSMCs.

STING1 targets MYH9 to drive adipogenesis through the AKT/GSK3β/β-catenin pathway

Stimulator of interferon response cGAMP interactor 1 (STING1), as an innate immune adaptor protein that mediates DNA sensing, has attracted tremendous biomedical interest. However, several recent researches have revealed the key role of STING1 in regulating the metabolic pathway. Here, we investigated its role in adipocyte differentiation. Preadipocytes with lentivirus-mediated Sting1 knockdown or overexpression were constructed to examine the effect of STING1 on adipocyte differentiation in vitro. Proteomics was performed in adipocytes to explore the mechanisms by which STING1 exerts pro-adipogenesis effects. Coimmunoprecipitation (CoIP)/mass spectrometry (MS) assay were used to identify the interacting partners of STING1. Our results showed that STING1 was upregulated during adipogenic differentiation of 3T3-L1 and white adipose tissue-derived stromal vascular precursor cells (WAT-SVF), accompanied by upregulation of adipocyte marker genes, peroxisome proliferator-activated receptor gamma (Pparg) and CCAAT/enhancer-binding protein beta (Cebpβ). Knockdown or overexpression of Sting1 altered adipogenesis in adipocytes. Mechanistically, proteomics and CoIP/MS assay revealed that STING1 targets non-muscle myosin protein (MYH9) to block its expression, which enhances AKT/GSK3β signaling and mediates β-catenin accumulation, affecting adipogenesis-related genes in adipocytes. These findings suggest that STING1 targeting combined with MYH9 regulates adipocyte differentiation through the AKT/GSK3β/β-catenin pathway. This is a new potential target for the treatment of hypertrophic adipose tissue, or obesity.

Qianyang Yuyin granules alleviate hypertension-induced vascular remodeling by inhibiting the phenotypic switch of vascular smooth muscle cells

ETHNOPHARMACOLOGICAL RELEVANCE

Qianyang Yuyin granules (QYYY) have been used clinically to treat hypertension for over two decades. Previous clinical trials have shown that QYYY can improve vascular elastic function in hypertensive patients. However, the underlying pharmacological mechanism is unclear.

AIM OF THE STUDY

To elucidate the effects and mechanisms of QYYY on vascular remodeling using a multidisciplinary approach that includes network pharmacology, proteomics, and both in vitro and in vivo experiments.

MATERIALS AND METHODS

The main components of QYYY were identified using ultra-high-performance liquid chromatography and high-resolution mass spectrometry. Network pharmacology and molecular docking were employed to predict QYYY's primary active ingredients, potential therapeutic targets and intervention pathways in hypertensive vascular remodeling. We induced hypertension in male C57BL/6 mice by infusing angiotensin II (Ang II) via osmotic minipumps, and performed pre-treatment with QYYY or Sacubitril/valsartan (Entresto). Blood pressure was monitored in vivo, followed by the extraction of aortas to examine pathological structural changes and alterations in protein expression patterns. The expression and location of proteins involved in the HIF-1α/TWIST1/P-p65 signaling pathway were investigated, as well as markers of vascular smooth muscle cells (VSMCs) phenotypic switch. In vitro, we studied the effects of QYYY water extract on Ang II-stimulated human aortic VSMCs. We investigated whether QYYY could affect the HIF-1α/TWIST1/P-p65 signaling pathway, thereby ameliorating apoptosis, autophagy, and phenotype switch in VSMCs.

RESULTS

We identified 62 main compounds in QYYY, combined with network pharmacology, speculated 827 potentially active substances, and explored 1021 therapeutic targets. The KEGG pathway analysis revealed that the mechanisms of action associated with QYYY therapy potentially encompass various biological processes, including metabolic pathways, TNF signaling pathways, apoptosis, Ras signaling pathways, HIF-1 signaling pathways, autophagy-animal pathways. In hypertensive mice, QYYY restored abnormally elevated blood pressure, vascular remodeling, and inflammation with a dose-response relationship while altering abnormal protein patterns. In vitro, QYYY could inhibit abnormal proliferation, migration, intracellular Ca2+ accumulation and cytoskeletal changes of VSMCs. It improved mitochondrial function, reduced ROS levels, stabilized membrane potential, prevented cell death, and reduced overproduction of TGF-β1, TNF-a, and IL-1β.

CONCLUSION

QYYY may be able to inhibit the overactivation of the HIF-1α/TWIST1/P-p65 signaling pathway, improve the phenotypic switch, and balance apoptosis and autophagy in VSMCs, thereby effectively improving vascular remodeling caused by hypertension.

NAT10 promotes vascular remodelling via mRNA ac4C acetylation

BACKGROUND AND AIMS

Vascular smooth muscle cell (VSMC) phenotype switching is a pathological hallmark in various cardiovascular diseases. N4-acetylcytidine (ac4C) catalyzed by N-acetyltransferase 10 (NAT10) is well conserved in the enzymatic modification of ribonucleic acid (RNA). NAT10-mediated ac4C acetylation is involved in various physiological and pathological processes, including cardiac remodelling. However, the biological functions and underlying regulatory mechanisms of mRNA ac4C modifications in vascular diseases remain elusive.

METHODS

By combining in-vitro and in-vivo vascular injury models, NAT10 was identified as a crucial protein involved in the promotion of post-injury neointima formation, as well as VSMC phenotype switching. The potential mechanisms of NAT10 in the vascular neointima formation were clarified by RNA sequence (RNA-seq), acetylated mRNA immunoprecipitation sequence (acRIP-seq), and RNA binding protein immunoprecipitation sequence (RIP-seq).

RESULTS

NAT10 and ac4C modifications were upregulated in injured human and rodent arteries. Deletion of NAT10 in VSMCs effectively reduced post-injury neointima formation and VSMC phenotype switching. Further RNA-seq, RIP-seq, and acRIP-seq revealed that NAT10, by its ac4C modification, directly interacts with genes, including integrin-β1 (ITGB1) and collagen type I alpha 2 chain (Col1a2) mRNAs. Taking ITGB1 as one example, it showed that NAT10-mediated ac4C consequently increased ITGB1 mRNA stability and its downstream focal adhesion kinase (FAK) signaling, directly influencing the proliferation of VSMCs and vascular remodelling. The regulation of NAT10 on the VSMC phenotype is of translational significance because the administration of Remodelin, a NAT10 inhibitor, effectively prevents neointima formation by suppressing VSMC proliferation and downregulating ITGB1 expression and deactivating its FAK signaling.

CONCLUSIONS

This study reveals that NAT10 promotes vascular remodelling via mRNA ac4C acetylation, which may be a promising therapeutic target against vascular remodelling.

Epigenetic modifications and emerging therapeutic targets in cardiovascular aging and diseases

The complex mechanisms underlying the development of cardiovascular diseases remain not fully elucidated. Epigenetics, which modulates gene expression without DNA sequence changes, is shedding light on these mechanisms and their heritable effects. This review focus on epigenetic regulation in cardiovascular aging and diseases, detailing specific epigenetic enzymes such as DNA methyltransferases (DNMTs), histone acetyltransferases (HATs), and histone deacetylases (HDACs), which serve as writers or erasers that modify the epigenetic landscape. We also discuss the readers of these modifications, such as the 5-methylcytosine binding domain proteins, and the erasers ten-eleven translocation (TET) proteins. The emerging role of RNA methylation, particularly N6-methyladenosine (m6A), in cardiovascular pathogenesis is also discussed. We summarize potential therapeutic targets, such as key enzymes and their inhibitors, including DNMT inhibitors like 5-azacytidine and decitabine, HDAC inhibitors like belinostat and givinotide, some of which have been approved by the FDA for various malignancies, suggesting their potential in treating cardiovascular diseases. Furthermore, we highlight the role of novel histone modifications and their associated enzymes, which are emerging as potential therapeutic targets in cardiovascular diseases. Thus, by incorporating the recent studies involving patients with cardiovascular aging and diseases, we aim to provide a more detailed and updated review that reflects the advancements in the field of epigenetic modification in cardiovascular diseases.

Oviduct Glycoprotein 1 (OVGP1) Diagnoses Polycystic Ovary Syndrome (PCOS) Based on Machine Learning Algorithms

Aims: To investigate the diagnostic value of oviduct glycoprotein 1 (OVGP1) levels for polycystic ovary syndrome (PCOS). Materials and Methods: Serum OVGP1 concentrations were measured by enzyme-linked immunosorbent assay (ELISA). Associations between OVGP1 and endocrine parameters were evaluated by Spearman's correlation analysis. Diagnostic capacity was assessed by utilizing machine learning algorithms and receiver operating characteristic (ROC) curves. Results: OVGP1 levels were significantly decreased in PCOS patients and correlated with the serum follicle-stimulating hormone (FSH) concentration and the luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio, which are predictors of PCOS occurrence. The diagnostic value of OVGP1 combined with six signatures (LH/FSH, progesterone, total cholesterol, triglyceride, high-density lipoprotein cholesterol, and anti-Müllerian hormone) or three clinical indicators has the potential to significantly improve the accuracy of diagnosing PCOS patients. Conclusion: OVGP1 enhances the ability to diagnose when combined with clinical indicators.

Heliox ventilation in elderly, hypertensive ICU patients improves microcirculation: A randomized controlled study

BACKGROUND

Conventional mechanical ventilation has adverse impacts on the hemodynamics of elderly, hypertensive ICU patients. Limited studies have addressed ways to ameliorate these negative effects. This study aimed to determine whether heliox ventilation could improve the hemodynamics, especially microcirculation, of elderly, hypertensive patients undergoing mechanical ventilation.

METHODS

Thirty-eight patients, over the age of 65 with essential hypertension who underwent invasive mechanical ventilation treatment, were divided into two groups: a control group of nitrogen‑oxygen ventilation (n = 19) and an experimental group of heliox ventilation (n = 19). The control group received conventional room air ventilation and the experimental group adopted the innovative, closed heliox ventilation technique. Changes in blood pressure, heart rate (HR), peripheral oxygen saturation (SpO2), central venous oxygen saturation (ScvO2), regional cerebral oxygen saturation (rSO2), lactic acid (Lac) and airway pressure were measured at 0,1,2,3 h under volume-controlled ventilation (VCV) mode throughout the study. Sublingual microcirculation parameters were additionally measured at 0 h and 3 h of ventilation treatment.

RESULTS

SpO2 in both groups increased after 1 h of ventilation compared with 0 h (p < 0.001), subsequently remaining stable. Compared with the control group, the experimental group showed a decrease in airway pressure and Lac, while blood pressure, ScvO2, and rSO2 increased (p < 0.05). Moreover, the sublingual microcirculation indexes in the experimental group improved compared with the control group (p < 0.05).

CONCLUSIONS

Heliox ventilation improves blood pressure and microcirculation in elderly hypertensive patients and may resolve the limitations of traditional nitrogen‑oxygen ventilation.

TRIAL REGISTRATION

This trial was registered. The Chinese trial registration number is ChiCTR2100043945. The date of registration is 6-3-2021.

Exploring the nexus between MYH9 and tumors: novel insights and new therapeutic opportunities

The myosin heavy chain 9 (MYH9) gene, located on human chromosome 22, encodes non-muscle myosin heavy chain IIA (NM IIA). This protein is essential to various cellular events, such as generating intracellular chemomechanical force and facilitating the movement of the actin cytoskeleton. Mutations associated with thrombocytopenia in autosomal dominant diseases first highlighted the significance of the MYH9 gene. In recent years, numerous studies have demonstrated the pivotal roles of MYH9 in various cancers. However, its effects on cancer are intricate and not fully comprehended. Furthermore, the elevated expression of MYH9 in certain malignancies suggests its potential as a target for tumor therapy. Nonetheless, there is a paucity of literature summarizing MYH9's role in tumors and the therapeutic strategies centered on it, necessitating a systematic analysis. This paper comprehensively reviews and analyzes the pertinent literature in this domain, elucidating the fundamental structural characteristics, biological functions, and the nexus between MYH9 and tumors. The mechanisms through which MYH9 contributes to tumor development and its multifaceted roles in the tumorigenic process are also explored. Additionally, we discuss the relationship between MYH9-related diseases (MYH9-RD) and tumors and also summarize tumor therapeutic approaches targeting MYH9. The potential clinical applications of studying the MYH9 gene include improving early diagnosis, clinical staging, and prognosis of tumors. This paper is anticipated to provide novel insights for tumor therapy.

TRIM58 downregulation maintains stemness via MYH9-GRK3-YAP axis activation in triple-negative breast cancer stem cells

TRIM58 is a member of the TRIM protein family, which possess with E3 ubiquitin ligase activities. Studies have revealed that low expression of TRIM58 plays key roles, has been implicated in the tumor progression of tumor formation due to its reduced expression. However, its role in regulating the stemness of breast cancer stem cells (CSCs) remains unexplored. Here, we found that TRIM58 was underexpressed in TNBC tissues and cells compared to adjacent mucosa tissue, and its downregulation was significantly associated with shorter survival. Overexpression of TRIM58 reduced the proportion of CD44 + /CD24- cells, upregulated differentiation genes, and inhibited stemness-related gene expression in TNBC CSCs. In vitro and in vivo experiments revealed that TRIM58 overexpression in CSCs suppressed tumor sphere formation and tumorigenic capacity. Co-IP results indicated direct interaction between TRIM58 and MYH9, with TRIM58 inducing MYH9 degradation via ubiquitination in differentiated cells. Label-free quantitative proteomics identified GRK3 and Hippo-YAP as downstream targets and signaling pathways of MYH9. TIMER database analysis, immunohistochemistry, western blotting, DNA-protein pulldown experiments, and dual luciferase reporter assays demonstrated that MYH9 regulated GRK3 transcriptional activation in CSCs. In conclusion, elevated TRIM58 expression in CSCs downregulates MYH9 protein levels by promoting ubiquitin-mediated degradation, thereby inhibiting downstream GRK3 transcription, inactivating the YAP stemness pathway, and ultimately promoting CSC differentiation.

MiRNA-miRNA interaction network in peripheral blood of patients with myocardial infarction: a gene expression meta-analysis

In recent years, investigations have revealed that microRNAs (miRNAs) can bind together and form a miRNA-miRNA-mRNA regulatory network that alters the consequence of miRNA-mRNA interaction. If we consider the miRNA that binds to mRNA as the primary miRNA and the miRNA that binds to the primary miRNA as the secondary one, secondry miRNAs can act as master regulators upstream of primary miRNAs and their target mRNAs. One of the distinguishing characteristics of secondary miRNAs as master regulators within a diverse set of differentially expressed genes is the absence of direct target mRNA for them. Instead, these master regulators exclusively govern the regulation of miRNAs that target specific mRNAs. Through in silico analysis, we identified 18 miRNAs among 385 differentially expressed miRNAs (DEmiRNAs) with no direct target mRNAs among 58 differentially expressed mRNAs (DEmRNAs) in peripheral blood of patients with myocardial infarction (MI). Instead, these secondary miRNAs targeted 9 primary miRNAs that had 36 direct targets among 58 DEmRNAs. We found that one primary miRNA might be regulated by more than one secondary miRNAs and each secondary miRNA can target more than one primary miRNAs. Among identified miRNA-miRNA-mRNA networks miR-188-5p/miR-299-3p/natural killer cell granule protein (NKG7), miR-200a-3p/miR-199b-5p/granzyme B (GZMB), and miR-377-3p/miR-581/oviductal glycoprotein 1 (OVGP1) exhibited higher scors in terms of expression levels (>2-fold increase or decrease) and strengh of interactions (ΔG < -5). Given the extensive network of miRNA interactions, focusing on master regulators opens up avenues for identifying key regulatory nodes for more effective therapeutic strategies.

Causality-enriched epigenetic age uncouples damage and adaptation

Machine learning models based on DNA methylation data can predict biological age but often lack causal insights. By harnessing large-scale genetic data through epigenome-wide Mendelian randomization, we identified CpG sites potentially causal for aging-related traits. Neither the existing epigenetic clocks nor age-related differential DNA methylation are enriched in these sites. These CpGs include sites that contribute to aging and protect against it, yet their combined contribution negatively affects age-related traits. We established a new framework to introduce causal information into epigenetic clocks, resulting in DamAge and AdaptAge-clocks that track detrimental and adaptive methylation changes, respectively. DamAge correlates with adverse outcomes, including mortality, while AdaptAge is associated with beneficial adaptations. These causality-enriched clocks exhibit sensitivity to short-term interventions. Our findings provide a detailed landscape of CpG sites with putative causal links to lifespan and healthspan, facilitating the development of aging biomarkers, assessing interventions, and studying reversibility of age-associated changes.

Disease Diagnosis Based on Nucleic Acid Modifications

Nucleic acid modifications include a wide range of epigenetic and epitranscriptomic factors and impact a wide range of nucleic acids due to their profound influence on biological inheritance, growth, and metabolism. The recently developed methods of mapping and characterizing these modifications have promoted their discovery as well as large-scale studies in eukaryotes, especially in humans. Because of these pioneering strategies, nucleic acid modifications have been shown to have a great impact on human disorders such as cancer. Therefore, whether nucleic acid modifications could become a new type of biomarker remains an open question. In this review, we briefly look back at classical nucleic acid modifications and then focus on the progress made in investigating these modifications as diagnostic biomarkers in clinical therapy and present our perspective on their development prospects.

circACTA2 inhibits NLRP3 inflammasome-mediated inflammation via interacting with NF-κB in vascular smooth muscle cells

circACTA2 derived from the smooth muscle α-actin gene plays an important role in the regulation of vascular smooth muscle cell (VSMC) phenotype. The activation of NLRP3 inflammasome is involved in VSMC phenotypic switching. However, the mechanistic relationship between circACTA2 and NLRP3 inflammasome during vascular remodeling remains poorly understood. Here, we showed that circACTA2 was down-regulated in human intimal hyperplasia. circACTA2 overexpression in circACTA2 transgenic mice significantly decreased the neointimal hyperplasia induced by vascular injury, which is concomitant with a decrease in IL-18, IL-1β, TNF-α, and IL-6 levels. Gain- and loss-of-function studies revealed that circACTA2 alleviated VSMC inflammation by suppressing the activation of NLRP3 inflammasome. Mechanistically, circACTA2 inhibited the expression of NF-κB p65 and p50 subunits and interacted with p50, which impedes the formation of the p50/p65 heterodimer and nuclear translocation induced by TNF-α, thus resulting in the suppression of NLRP3 gene transcription and inflammasome activation. Furthermore, circACTA2 overexpression mitigated inflammation via repressing NLRP3 inflammasome-mediated VSMC pyroptosis. Importantly, employing a decoy oligonucleotide to compete with circACTA2 for binding to p50 could attenuate the expression of NLRP3, ASC, and caspase-1. These findings provide a novel insight into the functional roles of circACTA2 in VSMCs, and targeting the circACTA2-NF-κB-NLRP3 axis represents a promising therapeutic strategy for vascular remodeling.

Epigenetic Signatures in Hypertension

Clear epigenetic signatures were found in hypertensive and pre-hypertensive patients using DNA methylation data and neural networks in a classification algorithm. It is shown how by selecting an appropriate subset of CpGs it is possible to achieve a mean accuracy classification of 86% for distinguishing control and hypertensive (and pre-hypertensive) patients using only 2239 CpGs. Furthermore, it is also possible to obtain a statistically comparable model achieving an 83% mean accuracy using only 22 CpGs. Both of these approaches represent a substantial improvement over using the entire amount of available CpGs, which resulted in the neural network not generating accurate classifications. An optimization approach is followed to select the CpGs to be used as the base for a model distinguishing between hypertensive and pre-hypertensive individuals. It is shown that it is possible to find methylation signatures using machine learning techniques, which can be applied to distinguish between control (healthy) individuals, pre-hypertensive individuals and hypertensive individuals, illustrating an associated epigenetic impact. Identifying epigenetic signatures might lead to more targeted treatments for patients in the future.