High salt diet inhibits the expression of Bmal1 and promotes atrial fibrosis and vulnerability to atrial fibrillation in Dahl salt sensitive rats

BACKGROUND

Hypertension is a risk factor for atrial fibrillation (AF), and brain and muscle arnt-like protein 1 (Bmal1) regulate circadian blood pressure and is implicated in several fibrotic disorders. Our hypothesis that Bmal1 inhibits atrial fibrosis and susceptibility to AF in salt-sensitive hypertension (SSHT) and our study provide a new target for the pathogenesis of AF induced by hypertension.

METHODS

The study involved 7-week-old male Dahl salt-sensitive that were fed either a high-salt diet (8% NaCl; DSH group) or a normal diet (0.3% NaCl; DSN group). An experimental model was used to measure systolic blood pressure (SBP), left atrial ejection fraction (LAEF), left atrial end-volume index (LAEVI), left atrial index (LAFI), AF inducibility, AF duration, and atrial fibrosis pathological examination and the expression of Baml1 and fibrosis-related proteins (TNF-α and α-SMA) in left atrial tissue.

RESULTS

DSH increased TNF-α and α-SMA expression in atrial tissue, level of SBP and LAESVI, atrial fibrosis, AF induction rate and AF duration, and decreased Bmal1 expression in atrial tissue, circadian rhythm of hypertension and level of LAEF and LAFI. Our results also showed that the degree of atrial fibrosis was negatively correlated with Bmal1 expression, but positively correlated with the expression of TNF-α and α-SMA.

CONCLUSIONS

We demonstrated that a high-salt diet leads to circadian changes in hypertension due to reduction Bmal1 expression, which plays a crucial role in atrial fibrosis and increased susceptibility to AF in SSHT rats.

TRIM65 promotes vascular smooth muscle cell phenotypic transformation by activating PI3K/Akt/mTOR signaling during atherogenesis

BACKGROUND AND AIMS

Tripartite motif (TRIM65) is an important member of the TRIM protein family, which is a newly discovered E3 ligase that interacts with and ubiquitinates various substrates and is involved in diverse pathological processes. However, the function of TRIM65 in atherosclerosis remains unarticulated. In this study, we investigated the role of TRIM65 in the pathogenesis of atherosclerosis, specifically in vascular smooth muscle cells (VSMCs) phenotype transformation, which plays a crucial role in formation of atherosclerotic lesions.

METHODS AND RESULTS

Both non-atherosclerotic and atherosclerotic lesions during autopsy were collected singly or pairwise from each individual (n = 16) to investigate the relationship between TRIM65 and the development of atherosclerosis. In vivo, Western diet-fed ApoE-/- mice overexpressing or lacking TRIM65 were used to assess the physiological function of TRIM65 on VSMCs phenotype, proliferation and atherosclerotic lesion formation. In vitro, VSMCs phenotypic transformation was induced by platelet-derived growth factor-BB (PDGF-BB). TRIM65-overexpressing or TRIM65-abrogated primary mouse aortic smooth muscle cells (MOASMCs) and human aortic smooth muscle cells (HASMCs) were used to investigate the mechanisms underlying the progression of VSMCs phenotypic transformation, proliferation and migration. Increased TRIM65 expression was detected in α-SMA-positive cells in the medial and atherosclerotic lesions of autopsy specimens. TRIM65 overexpression increased, whereas genetic knockdown of TRIM65 remarkably inhibited, atherosclerotic plaque development. Mechanistically, TRIM65 overexpression activated PI3K/Akt/mTOR signaling, resulting in the loss of the VSMCs contractile phenotype, including calponin, α-SMA, and SM22α, as well as cell proliferation and migration. However, opposite phenomena were observed when TRIM65 was deficient in vivo or in vitro. Moreover, in cultured PDGF-BB-induced TRIM65-overexpressing VSMCs, inhibition of PI3K by treatment with the inhibitor LY-294002 for 24 h markedly attenuated PI3K/Akt/mTOR activation, regained the VSMCs contractile phenotype, and blocked the progression of cell proliferation and migration.

CONCLUSIONS

TRIM65 overexpression enhances atherosclerosis development by promoting phenotypic transformation of VSMCs from contractile to synthetic state through activation of the PI3K/Akt/mTOR signal pathway.

Correlation of Gut Microbiota with Children Obesity and Weight Loss

Children obesity is a serious public health problem drawing much attention around the world. Recent research indicated that gut microbiota plays a vital role in children obesity, and disturbed gut microbiota is a prominent characteristic of obese children. Diet and exercise are efficient intervention for weight loss in obesity children, however, how the gut microbiota is modulated which remains largely unknown. To characterize the feature of gut microbiota in obese children and explore the effect of dietary and exercise on gut microbiota in simple obese children, 107 healthy children and 86 obese children were recruited, and among of the obese children 39 received the dietary-exercise combined weight loss intervention (DEI). The gut microbiota composition was detected by the 16S amplicon sequencing method. The gut microbiota composition was significantly different between obese children and the healthy cohort, and DEI significantly reduced the body weight and ameliorated the gut microbiota dysbiosis. After DEI, the abundance of the Akkermansia muciniphila was increased, while the abundance of the Sutterella genus was decreased in simple obese children. Our results may provide theoretical reference for future personalized obesity interventions based on gut microbiota.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12088-023-01088-3.

Multifaceted Nature of HuR in Atherosclerosis Development

HuR (Human antigen R) is an RNA binding protein (RBP) that specifically binds to certain RNA sequences, influencing post-transcriptional regulation. HuR is primarily involved in tumor regulation, as well as cell growth, proliferation, inflammation, and angiogenesis. HuR is implicated in endothelial activation, smooth muscle proliferation, inflammatory response, macrophage apoptosis, lipid regulation, and autophagy, playing a crucial regulatory role in atherosclerosis. Accumulating evidence suggests that HuR has dual roles in AS. On the one hand, HuR expedites the development of AS by facilitating endothelial activation, smooth muscle proliferation, and inflammation. On the contrary, it exerts beneficial effects by reducing macrophage apoptosis, regulating lipid efflux, and increasing autophagy. In this review, we aim to provide a comprehensive summary of the role of HuR in the development of AS by examining its involvement in cellular mechanisms, inflammation, autophagy, and apoptosis. Additionally, we discuss the mechanisms of drugs that target HuR, with the goal of offering new perspectives for the treatment of AS.

Hydrogen sulfide attenuates atherosclerosis induced by low shear stress by sulfhydrylating endothelium NFIL3 to restrain MEST mediated endothelial mesenchymal transformation

BACKGROUND

Endothelial-mesenchymal transition (EndMT) induced by low shear stress plays an important role in the development of atherosclerosis. However, little is known about the correlation between hydrogen sulfide (H2S), a protective gaseous mediator in atherosclerosis and the process of EndMT.

METHODS

We constructed a stable low-shear-stress-induced(2 dyn/cm2) EndMT model, acombined with the pretreatment method of hydrogen sulfide slow release agent(GYY4137). The level of MEST was detected in the common carotid artery of ApoE-/- mice with local carotid artery ligation. The effect of MEST on atherosclerosis development in vivo was verified using ApoE-/- mice were given tail-vein injection of endothelial-specific overexpressed and knock-down MEST adeno-associated virus (AAV).

RESULTS

These findings confirmed that MEST is up-regulated in low-shear-stress-induced EndMT and atherosclerosis. In vivo experiments showed that MEST gene overexpression significantly promoted EndMT and aggravated the development of atherosclerotic plaques and MEST gene knockdown significantly inhibited EndMT and delayed the process of atherosclerosis. In vitro, H2S inhibits the expression of MEST and EndMT induced by low shear stress and inhibits EndMT induced by MEST overexpression. Knockdown of NFIL3 inhibit the up regulation of MEST and EndMT induced by low shear stress in HUVECs. CHIP-qPCR assay and Luciferase Reporter assay confirmed that NFIL3 binds to MEST DNA, increases its transcription and H2S inhibits the binding of NFIL3 and MEST DNA, weakening NFIL3's transcriptional promotion of MEST. Mechanistically, H2S increased the sulfhydrylation level of NFIL3, an important upstream transcription factors of MEST. In part, transcription factor NFIL3 restrain its binding to MEST DNA by sulfhydration.

CONCLUSIONS

H2S negatively regulate the expression of MEST by sulfhydrylation of NFIL3, thereby inhibiting low-shear-stress-induced EndMT and atherosclerosis.

LncRNA-mediated Modulation of Endothelial Cells: Novel Progress in the Pathogenesis of Coronary Atherosclerotic Disease

Coronary atherosclerotic disease (CAD) is a common cardiovascular disease and an important cause of death. Moreover, endothelial cells (ECs) injury is an early pathophysiological feature of CAD, and long noncoding RNAs (lncRNAs) can modulate gene expression. Recent studies have shown that lncRNAs are involved in the pathogenesis of CAD, especially by regulating ECs. In this review, we summarize the novel progress of lncRNA-modulated ECs in the pathogenesis of CAD, including ECs proliferation, migration, adhesion, angiogenesis, inflammation, apoptosis, autophagy, and pyroptosis. Thus, as lncRNAs regulate ECs in CAD, lncRNAs will provide ideal and novel targets for the diagnosis and drug therapy of CAD.

Pharmacological inhibition of MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1) induces ferroptosis in vascular smooth muscle cells

MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1) is a human paracaspase protein with proteolytic activity via its caspase-like domain. The pharmacological inhibition of MALT1 by MI-2, a specific chemical inhibitor, diminishes the response of endothelial cells to inflammatory stimuli. However, it is largely unknown how MALT1 regulates the functions of vascular smooth muscle cells (SMCs). This study aims to investigate the impact of MALT1 inhibition by MI-2 on the functions of vascular SMCs, both in vitro and in vivo. MI-2 treatment led to concentration- and time-dependent cell death of cultured aortic SMCs, which was rescued by the iron chelator deferoxamine (DFO) or ferrostatin-1 (Fer-1), a specific inhibitor of ferroptosis, but not by inhibitors of apoptosis (Z-VAD-fmk), pyroptosis (Z-YVAD-fmk), or necrosis (Necrostatin-1, Nec-1). MI-2 treatment downregulated the expression of glutathione peroxidase 4 (GPX4) and ferritin heavy polypeptide 1 (FTH1), which was prevented by pre-treatment with DFO or Fer-1. MI-2 treatment also activated autophagy, which was inhibited by Atg7 deficiency or bafilomycin A1 preventing MI-2-induced ferroptosis. MI-2 treatment reduced the cleavage of cylindromatosis (CYLD), a specific substrate of MALT1. Notably, MI-2 treatment led to a rapid loss of contractility in mouse aortas, which was prevented by co-incubation with Fer-1. Moreover, local application of MI-2 significantly reduced carotid neointima lesions and atherosclerosis in C57BL/6J mice and apolipoprotein-E knockout (ApoE-/-) mice, respectively, which were both ameliorated by co-treatment with Fer-1. In conclusion, the present study demonstrated that MALT1 inhibition induces ferroptosis of vascular SMCs, likely contributing to its amelioration of proliferative vascular diseases.

Biological functions of CRTC2 and its role in metabolism-related diseases

CREB-regulated transcription coactivator2 (CRTC2 or TORC2) is a transcriptional coactivator of CREB(cAMP response element binding protein), which affects human energy metabolism through cyclic adenosine phosphate pathway, Mammalian target of rapamycin (mTOR) pathway, Sterol regulatory element binding protein 1(SREBP1), Sterol regulatory element binding protein 2 (SREBP2) and other substances Current studies on CRTC2 mainly focus on glucose and lipid metabolism, relevant studies show that CRTC2 can participate in the occurrence and development of related diseases by affecting metabolic homeostasis. It has been found that Crtc2 acts as a signaling regulator for cAMP and Ca2 + signaling pathways in many cell types, and phosphorylation at ser171 and ser275 can regulate downstream biological functions by controlling CRTC2 shuttling between cytoplasm and nucleus.

TRIM65 Suppresses oxLDL-induced Endothelial Inflammation by Interaction with VCAM-1 in Atherogenesis

BACKGROUND AND OBJECTIVE

Endothelial cell activation, characterized by increased levels of vascular cell adhesion molecule 1 (VCAM-1), plays a crucial role in the development of atherosclerosis (AS). Therefore, inhibition of VCAM-1-mediated inflammatory response is of great significance in the prevention and treatment of AS. The tripartite motif (TRIM) protein-TRIM65 is involved in the regulation of cancer development, antivirals and inflammation. We aimed to study the functions of TRIM65 in regulating endothelial inflammation by interacting with VCAM-1 in atherogenesis.

METHODS AND RESULTS

In vitro, we report that human umbilical vein endothelial cells (HUVECs) treated with oxidized low-density lipoprotein (oxLDL) significantly upregulate the expression of TRIM65 in a time- and dose-dependent manner. Overexpression of TRIM65 reduces oxLDL-triggered VCAM-1 protein expression, decreases monocyte adhesion to HUVECs and inhibits the production of the inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α as well as endothelial oxLDL transcytosis. In contrast, siRNA-mediated knockdown of TRIM65 promotes the expression of VCAM-1, resulting in increased adhesion of monocytes and the release of the inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α and enhances endothelial oxLDL transcytosis. In vivo, we measured the high expression of TRIM65 in ApoE-/- mouse aortic plaques compared to C57BL/6J mouse aortic plaques. Then, we examined whether the blood levels of VCAM-1 were higher in TRIM65 knockout ApoE-/- mice than in control mice induced by a Western diet. Furthermore, Western blot results showed that the protein expression of VCAM-1 was markedly enhanced in TRIM65 knockout ApoE-/- mouse aortic tissues compared to that of the controls. Immunofluorescence staining revealed that the expression of VCAM-1 was significantly increased in atherosclerotic plaques of TRIM65-/-/ApoE-/- aortic vessels compared to ApoE-/- controls. Mechanistically, TRIM65 specifically interacts with VCAM-1 and targets it for K48-linked ubiquitination.

CONCLUSION

Our studies indicate that TRIM65 attenuates the endothelial inflammatory response by targeting VCAM-1 for ubiquitination and provides a potential therapeutic target for the inhibition of endothelial inflammation in AS.

Impact of Short-Term (+)-JQ1 Exposure on Mouse Aorta: Unanticipated Inhibition of Smooth Muscle Contractility

(+)-JQ1, a specific chemical inhibitor of bromodomain and extraterminal (BET) family protein 4 (BRD4), has been reported to inhibit smooth muscle cell (SMC) proliferation and mouse neointima formation via BRD4 regulation and modulate endothelial nitric oxide synthase (eNOS) activity. This study aimed to investigate the effects of (+)-JQ1 on smooth muscle contractility and the underlying mechanisms. Using wire myography, we discovered that (+)-JQ1 inhibited contractile responses in mouse aortas with or without functional endothelium, reducing myosin light chain 20 (LC20) phosphorylation and relying on extracellular Ca2+. In mouse aortas lacking functional endothelium, BRD4 knockout did not alter the inhibition of contractile responses by (+)-JQ1. In primary cultured SMCs, (+)-JQ1 inhibited Ca2+ influx. In aortas with intact endothelium, (+)-JQ1 inhibition of contractile responses was reversed by NOS inhibition (L-NAME) or guanylyl cyclase inhibition (ODQ) and by blocking the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway. In cultured human umbilical vein endothelial cells (HUVECs), (+)-JQ1 rapidly activated AKT and eNOS, which was reversed by PI3K or ATK inhibition. Intraperitoneal injection of (+)-JQ1 reduced mouse systolic blood pressure, an effect blocked by co-treatment with L-NAME. Interestingly, (+)-JQ1 inhibition of aortic contractility and its activation of eNOS and AKT were mimicked by the (-)-JQ1 enantiomer, which is structurally incapable of inhibiting BET bromodomains. In summary, our data suggest that (+)-JQ1 directly inhibits smooth muscle contractility and indirectly activates the PI3K/AKT/eNOS cascade in endothelial cells; however, these effects appear unrelated to BET inhibition. We conclude that (+)-JQ1 exhibits an off-target effect on vascular contractility.

Trim65 attenuates isoproterenol-induced cardiac hypertrophy by promoting autophagy and ameliorating mitochondrial dysfunction via the Jak1/Stat1 signaling pathway

Pathological cardiac hypertrophy is a major cause of heart failure, and there is no effective approach for its prevention or treatment. The Trim family is a recently identified family of E3 ubiquitin ligases that regulate cardiac hypertrophy. Trim65, which is a memberof the Trim family, previous studies have not determined whether Trim65 affects cardiac hypertrophy. In this study, the effects of Trim65 on isoproterenol (ISO)-induced cardiac hypertrophy and the underlying mechanisms were investigated. In contrast to C57BL/6 mice, Trim65-knockout (Trim65-KO) mice developed more severe myocardial hypertrophy, fibrosis and cardiac dysfunction after being intraperitoneally injected with ISO for 2 weeks. Transmission electron microscopy (TEM) revealed that the autophagic flux was inhibited, mitochondria were swollen, and mitochondrial cristae were lost or decreased in the myocardium of Trim65-KO mice. In vitro studies demonstrated that overexpression of Trim65 inhibited ISO-induced cardiomyocyte hypertrophy by increasing mitochondrial density and membrane potential, and the Stat1 inhibitor fludarabine attenuated the effect of Trim65 knockdown on ISO-induced cardiomyocyte hypertrophy by reducing Reactive oxygen species (ROS) production and increasing the mitochondrial density and membrane potential. Our findings provide the first link between Trim65 and mitochondria, and we found for the first time that Trim65 inhibits mitochondria-dependent apoptosis and autophagy via the Jak1/Stat1 signalling pathway, ultimately attenuating ISO-induced cardiac hypertrophy; this effect of Trim65 might be mediated via the regulation of Jak1 ubiquitination. Taking these findings together, we suggest that genes that are related to mitochondria-dependent apoptosis and that are associated with Trim65 could be promising therapeutic targets for cardiac hypertrophy.

Ferroptosis and Hydrogen Sulfide in Cardiovascular Disease

Ferroptosis is an iron-dependent cell death, characterized by the accumulation of lipid-reactive oxygen species; various regulatory mechanisms influence the course of ferroptosis. The rapid increase in cardiovascular diseases (CVDs) is an extremely urgent problem. CVDs are characterized by the progressive deterioration of the heart and blood vessels, eventually leading to circulatory system disorder. Accumulating evidence, however, has highlighted crucial roles of ferroptosis in CVDs. Hydrogen sulfide plays a significant part in anti-oxidative stress, which may participate in the general mechanism of ferroptosis and regulate it by some signaling molecules. This review has primarily summarized the effects of hydrogen sulfide on ferroptosis and cardiovascular disease, especially the antioxidative stress, and would provide a more effective direction for the clinical study of CVDs.

Understanding the Potential Function of Perivascular Adipose Tissue in Abdominal Aortic Aneurysms: Current Research Status and Future Expectation

Abstract:

An abdominal aortic aneurysm (AAA) is a progressive dilatation of the vascular wall occurring below the aortic fissure, preferably occurring below the renal artery. The molecular mechanism of AAA has not yet been elucidated. In the past few decades, research on abdominal aortic aneurysm has been mainly focused on the vessel wall, and it is generally accepted that inflammation and middle layer fracture of the vessel wall is the core steps in the development of AAA. However, perivascular adipose tissue plays a non-negligible role in the occurrence and development of AAA. The position of PVAT plays a supporting and protective role on the vascular wall, but the particularity of the location makes it not only have the physiological function of visceral fat; but also can regulate the vascular function by secreting a large number of adipokines and cytokines. An abdominal aortic aneurysm is getting higher and higher, with a vascular rupture, low rescue success rate, and extremely high lethality rate. At present, there is no drug to control the progression or reverse abdominal aortic aneurysm. Therefore, it is critical to deeply explore the mechanism of abdominal aortic aneurysms and find new therapeutic ways to inhibit abdominal aortic aneurysm formation and disease progression. An abdominal aortic aneurysm is mainly characterized by inflammation of the vessel wall and matrix metalloprotein degradation. In this review, we mainly focus on the cytokines released by the perivascular adipose tissue, summarize the mechanisms involved in the regulation of abdominal aortic aneurysms, and provide new research directions for studying abdominal aortic aneurysms.

PLK1 promotes cholesterol efflux and alleviates atherosclerosis by up-regulating ABCA1 and ABCG1 expression via the AMPK/PPARγ/LXRα pathway

Polo-like kinase 1 (PLK1) is a serine/threonine kinase involving lipid metabolism and cardiovascular disease. However, its role in atherogenesis has yet to be determined. The aim of this study was to observe the impact of PLK1 on macrophage lipid accumulation and atherosclerosis development and to explore the underlying mechanisms. We found a significant reduction of PLK1 expression in lipid-loaded macrophages and atherosclerosis model mice. Lentivirus-mediated overexpression of PLK1 promoted cholesterol efflux and inhibited lipid accumulation in THP-1 macrophage-derived foam cells. Mechanistic analysis revealed that PLK1 stimulated the phosphorylation of AMP-activated protein kinase (AMPK), leading to activation of the peroxisome proliferator-activated receptor γ (PPARγ)/liver X receptor α (LXRα) pathway and up-regulation of ATP binding cassette transporter A1 (ABCA1) and ABCG1 expression. Injection of lentiviral vector expressing PLK1 increased reverse cholesterol transport, improved plasma lipid profiles and decreased atherosclerotic lesion area in apoE-deficient mice fed a Western diet. PLK1 overexpression also facilitated AMPK and HSL phosphorylation and enhanced the expression of PPARγ, LXRα, ABCA1, ABCG1 and LPL in the aorta. In summary, these data suggest that PLK1 inhibits macrophage lipid accumulation and mitigates atherosclerosis by promoting ABCA1- and ABCG1-dependent cholesterol efflux via the AMPK/PPARγ/LXRα pathway.

Development of hydrogen sulfide donors for anti-atherosclerosis therapeutics research: Challenges and future priorities

Hydrogen sulfide (H₂S), a gas transmitter found in eukaryotic organisms, plays an essential role in several physiological processes. H₂S is one of the three primary biological gas transmission signaling mediators, along with nitric oxide and carbon monoxide. Several animal and in vitro experiments have indicated that H₂S can prevent coronary endothelial mesenchymal transition, reduce the expression of endothelial cell adhesion molecules, and stabilize intravascular plaques, suggesting its potential role in the treatment of atherosclerosis (AS). H₂S donors are compounds that can release H₂S under certain circumstances. Development of highly targeted H₂S donors is a key imperative as these can allow for in-depth evaluation of the anti-atherosclerotic effects of exogenous H₂S. More importantly, identification of an optimal H₂S donor is critical for the creation of H₂S anti-atherosclerotic prodrugs. In this review, we discuss a wide range of H₂S donors with anti-AS potential along with their respective transport pathways and design-related limitations. We also discuss the utilization of nano-synthetic technologies to manufacture H₂S donors. This innovative and effective design example sheds new light on the production of highly targeted H₂S donors.

Hippo: a new hub for atherosclerotic disease

Abstract:

Hippo,an evolutionarily conserved kinase cascade reaction in organisms,can respond to a set of signals,such as mechanical signals and cell metabolism,to maintain cell growth,differentiation,tissue/organ development and homeostasis.In the past ten years,HIPPO has controlled the development of tissues and organs by regulating the process of cell proliferation,especially in the field of cardiac regeneration after myocardial infarction.This suggests that HIPPO signaling is closely linked to cardiovascular disease.Atherosclerosis is the most common disease of the cardiovascular system. It is characterised by chronic inflammation of the vascular wall, mainly involving dysfunction of endothelial cells, smooth muscle cells and macrophages.Oxidized Low density lipoprotein (LDL) damages the barrier function of endothelial cells, which enter the middle membrane of the vascular wall, accelerates the formation of foam cells and promotes the occurrence and development of atherosclerosis.Autophagy is associated with the development of atherosclerosis.However, the mechanism of HIPPO regulation of atherosclerosis has not meant to clarified.In view of the pivotal role of this signaling pathway in maintaining cell growth,proliferation and differentiation,the imbalance of Hippo is related to atherosclerosis and related diseases.In this review,we emphasized Hippo as a hub for regulating atherosclerosis and discussed its potential targets in pathophysiology,human diseases,and related pharmacology.

TRIMs: Generalists Regulating the NLRP3 Inflammasome Signaling Pathway

Inflammation is a double-edged sword. The moderate inflammatory response is a fundamental defense mechanism produced by the body's resistance to dangerous stimuli and a repair process of the body itself. Increasing studies have confirmed that the overactivation of the inflammasome is involved in the occurrence and development of inflammatory diseases. Strictly controlling the overactivation of the inflammasome and preventing excessive inflammatory response have always been the research focus on inflammatory diseases. However, the endogenous regulatory mechanism of inflammasome is not completely clear. The tripartite motif (TRIM) protein is one of the members of E3 ligases in the process of ubiquitination. The universality and importance of the functions of TRIM members are recognized, including the regulation of inflammatory response. This article will focus on research on the relationship between TRIMs and NLRP3 Inflammasome, which may help us make some references for future related research and the discovery of treatment methods.

Protein tyrosine nitration in atherosclerotic endothelial dysfunction

Accumulation of reactive oxygen species (ROS) can induce both protein tyrosine nitration and endothelial dysfunction in atherosclerosis. Endothelial dysfunction refers to impaired endothelium-dependent vasorelaxation that can be triggered by an imbalance in nitric oxide (NO) production and consumption. ROS reacts with NO to generate peroxynitrite, decreasing NO bioavailability. Peroxynitrite also promotes protein tyrosine nitration in vivo that can affect protein structure and function and further damage endothelial function. In this review, we discuss the process of protein tyrosine nitration, increased expression of nitrated proteins in cardiovascular disease and their association with endothelial dysfunction, and the interference of tyrosine nitration with antioxidants and the protective role in endothelial dysfunction. These may lead us to the conception that protein tyrosine nitration may be one of the causes of endothelial dysfunction, and help us gain information about the mechanism of endothelial dysfunction underlying atherosclerosis.

Hydrogen Sulfide Ameliorates Angiotensin II-Induced Atrial Fibrosis Progression to Atrial Fibrillation Through Inhibition of the Warburg Effect and Endoplasmic Reticulum Stress

Atrial fibrosis is the basis for the occurrence and development of atrial fibrillation (AF) and is closely related to the Warburg effect, endoplasmic reticulum stress (ERS) and mitochondrion dysfunctions-induced cardiomyocyte apoptosis. Hydrogen sulfide (H₂S) is a gaseous signalling molecule with cardioprotective, anti-myocardial fibrosis and improved energy metabolism effects. Nevertheless, the specific mechanism by which H₂S improves the progression of atrial fibrosis to AF remains unclear. A case-control study of patients with and without AF was designed to assess changes in H₂S, the Warburg effect, and ERS in AF. The results showed that AF can significantly reduce cystathionine-γ-lyase (CSE) and 3-mercaptopyruvate thiotransferase (3-MST) expression and the H₂S level, induce cystathionine-β-synthase (CBS) expression; increase the Warburg effect, ERS and atrial fibrosis; and promote left atrial dysfunction. In addition, AngII-treated SD rats had an increased Warburg effect and ERS levels and enhanced atrial fibrosis progression to AF compared to wild-type SD rats, and these conditions were reversed by sodium hydrosulfide (NaHS), dichloroacetic acid (DCA) or 4-phenylbutyric acid (4-PBA) supplementation. Finally, low CSE levels in AngII-induced HL-1 cells were concentration- and time-dependent and associated with mitochondrial dysfunction, apoptosis, the Warburg effect and ERS, and these effects were reversed by NaHS, DCA or 4-PBA supplementation. Our research indicates that H₂S can regulate the AngII-induced Warburg effect and ERS and might be a potential therapeutic drug to inhibit atrial fibrosis progression to AF.

Sestrin2 in atherosclerosis

Atherosclerosis (AS) is the pathological basis of numerous lethal diseases, such as myocardial infarction, heart failure, and stroke. As we know, almost twenty million people worldwide die of the arterial diseases annually. Sestrin2 is a stress-inducing protein, which serves as a guardian by activating AMPK, inhibiting mTOR, and maintaining redox balance beneath various stress environments. A large number of studies show that Sestrin2 would shield the body from injury by stress. Moreover, it has been demonstrated that Sestrin2 is closely connected with AS. Here, this article reviewed the involvement of Sestrin2 in the pathogenesis of AS from four aspects: cellular mechanism, oxidative stress, inflammation, and lipid metabolism. Current evidence reveals that Sestrin2 is a novel target for the prevention and treatment of AS.

A promising field: regulating imbalance of EndMT in cardiovascular diseases

Endothelial-mesenchymal transition (EndMT) is widely involved in the occurrence and development of cardiovascular diseases. Although there is no direct evidence, it is very promising as an effective target for the treatment of these diseases. Endothelial cells need to respond to the complex cardiovascular environment through EndMT, but sustained stimuli will cause the imbalance of EndMT. Blocking the signal transduction promoting EndMT is an effective method to control the imbalance of EndMT. In particular, we also discussed the potential role of endothelial cell apoptosis and autophagy in regulating the imbalance of EndMT. In addition, promoting mesenchymal-endothelial transformation (MEndT) is also a method to control the imbalance of EndMT. However, targeting EndMT to treat cardiovascular disease still faces many challenges. By reviewing the research progress of EndMT, we have put forward some insights and translated them into challenges and opportunities for new treatment strategies for cardiovascular diseases.

EndMT: Potential Target of H2S against Atherosclerosis

Atherosclerosis is a chronic arterial wall illness that forms atherosclerotic plaques within the arteries. Plaque formation and endothelial dysfunction are atherosclerosis' characteristics. It is believed that the occurrence and development of atherosclerosis mainly include endothelial cell damage, lipoprotein deposition, inflammation and fibrous cap formation, but its molecular mechanism has not been elucidated. Therefore, protecting the vascular endothelium from damage is one of the key factors against atherosclerosis. The factors and processes involved in vascular endothelial injury are complex. Finding out the key factors and mechanisms of atherosclerosis caused by vascular endothelial injury is an important target for reversing and preventing atherosclerosis. Changes in cell adhesion are the early characteristics of EndMT, and cell adhesion is related to vascular endothelial injury and atherosclerosis. Recent researches have exhibited that endothelial-mesenchymal transition (EndMT) can urge atherosclerosis' progress, and it is expected that inhibition of EndMT will be an object for anti-atherosclerosis. We speculate whether inhibition of EndMT can become an effective target for reversing atherosclerosis by improving cell adhesion changes and vascular endothelial injury. Studies have shown that H₂S has a strong cardiovascular protective effect. As H₂S has anti- inflammatory, anti-oxidant, inhibiting foam cell formation, regulating ion channels and enhancing cell adhesion and endothelial functions, the current research on H₂S in cardiovascular aspects is increasing, but anti-atherosclerosis's molecular mechanism and the function of H2S in EndMT have not been explicit. In order to explore the mechanism of H₂S against atherosclerosis, to find an effective target to reverse atherosclerosis, we sum up the progress of EndMT promoting atherosclerosis, and Hydrogen sulfide's potential anti- EndMT effect is discussed in this review.

Multifunctional RNase MCPIP1 and its Role in Cardiovascular Diseases

Monocyte chemoattractant protein-1 induced protein 1 (MCPIP1), one of the MCPIP family members, is characterized by the presence of both C-x8-C-x5-C-x3-H (CCCH)- type zinc finger and PilT-N-terminal domains. As a potent regulator of innate immunity, MCPIP1 exerts anti-inflammatory effects through its ribonuclease (RNase) and deubiquitinating enzyme activities to degrade cytokine mRNAs and inhibit nuclear factor- kappa B (NF-κB), respectively. MCPIP1 is expressed not only in immune cells but also in many other cell types, including cardiomyocytes, vascular endothelial cells (ECs) and smooth muscle cells (SMCs). Increasing evidence indicates that MCPIP1 plays a role in the regulation of cardiac functions and is involved in the processes of vascular diseases, such as ischemia-reperfusion (I/R) and atherosclerosis. To better understand the emerging roles of MCPIP1 in the cardiovascular system, we reviewed the current literature with respect to MCPIP1 functions and discussed its association with the pathogenesis of cardiovascular diseases and the implication as a therapeutic target.

Effect of PCSK9 on Vascular Smooth Muscle Cell Functions: A New Player in Atherosclerosis

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a secretory serine protease that plays multiple biological functions in the regulation of physiological and pathological processes. PCSK9 inhibitors decrease the circulating LDL-cholesterol level with well-known preventive and therapeutic effects on atherosclerosis (AS), but increasing evidence shows that the direct impact of PCSK9 on the vascular wall also plays an important role in atherosclerotic progression. Compared with other vascular cells, a large proportion of PCSK9 is originated from vascular smooth muscle cells (VSMC). Therefore, defining the effect of VSMC-derived PCSK9 on response changes, such as phenotypic switch, apoptosis, autophagy, inflammation, foam cell formation, and calcification of VSMC, helps us better understand the "pleiotropic" effects of VSMC on the atherosclerotic process. In addition, our understanding of the mechanisms of PCSK9 controlling VSMC functions in vivo is far from enough. This review aims to holistically evaluate and analyze the current state of our knowledge regarding PCSK9 actions affecting on VSMC functions and its mechanism in atherosclerotic lesion development. A mechanistic understanding of PCSK9 effects on VSMC will further underpin the success of a new therapeutic strategy targeting AS.

Pulmonary Artery Smooth Muscle Cell Senescence Promotes the Proliferation of PASMCs by Paracrine IL-6 in Hypoxia-Induced Pulmonary Hypertension

Pulmonary hypertension (PH) is a critical and dangerous disease in cardiovascular system. Pulmonary vascular remodeling is an important pathophysiological mechanism for the development of pulmonary arterial hypertension. Pulmonary artery smooth muscle cell (PASMC) proliferation, hypertrophy, and enhancing secretory activity are the main causes of pulmonary vascular remodeling. Previous studies have proven that various active substances and inflammatory factors, such as interleukin 6 (IL-6), IL-8, chemotactic factor for monocyte 1, etc., are involved in pulmonary vascular remodeling in PH. However, the underlying mechanisms of these active substances to promote the PASMC proliferation remain to be elucidated. In our study, we demonstrated that PASMC senescence, as a physiopathologic mechanism, played an essential role in hypoxia-induced PASMC proliferation. In the progression of PH, senescence PASMCs could contribute to PASMC proliferation via increasing the expression of paracrine IL-6 (senescence-associated secretory phenotype). In addition, we found that activated mTOR/S6K1 pathway can promote PASMC senescence and elevate hypoxia-induced PASMC proliferation. Further study revealed that the activation of mTOR/S6K1 pathway was responsible for senescence PASMCs inducing PASMC proliferation via paracrine IL-6. Targeted inhibition of PASMC senescence could effectively suppress PASMC proliferation and relieve pulmonary vascular remodeling in PH, indicating a potential for the exploration of novel anti-PH strategies.

The prognostic value of modified NUTRIC score for patients in cardiothoracic surgery recovery unit: A retrospective cohort study

BACKGROUND

Malnutrition is highly prevalent in critically ill patients. The modified Nutrition Risk in the Critically ill (mNUTRIC) score has been introduced to evaluate the nutritional risk of patients in an intensive care unit (ICU). The mNUTRIC score is a predictive factor of mortality for patients in a medical or mixed ICU, whereas the relationship between mNUTRIC and prognosis of patients in a cardiothoracic surgery recovery unit (CSRU) is unclear and related researches are limited.

METHODS

We conducted this retrospective cohort study to explore the value of mNUTRIC score in CSRU patients. We identified totally 4059 patients from the Multiparameter Intelligent Monitoring in Intensive Care III (MIMIC III) database.

RESULTS

The optimal cut-off value of mNUTRIC score was 4 and a total of 1498 (36.9%) patients were considered to be at high nutritional risk (mNUTRIC ≥ 4). A multivariate logistic regression model indicated that patients at high nutritional risk have higher hospital mortality compared to those at low nutritional risk (odds ratio = 2.49, 95% confidence interval (CI) = 1.32-4.70, p = 0.005]. Furthermore, a Cox regression model was established adjusted for age, white blood cell and body mass index. The Kaplan-Meier curve indicated that patients at high nutritional risk have poorer 365-days [hazard ratio (HR) = 1.76, 95% CI = 1.30-2.37, p < 0.001] and 1000-days (HR = 2.30, 95% CI = 1.87-2.83, p < 0.001) overall survival.

CONCLUSIONS

The mNUTRIC score could not only predict hospital mortality, but also be an independent prognostic factor for long-term survival in CSRU patients. More well-designed clinical trials are needed to verify and update our findings.

Hydrogen sulfide improves ox‑LDL‑induced expression levels of Lp‑PLA2 in THP‑1 monocytes via the p38MAPK pathway

Hydrogen sulfide (H₂S) exerts an anti‑atherosclerotic effect and decreases foam cell formation. Lipoprotein‑associated phospholipase A2 (Lp‑PLA₂) is a key factor involved in foam cell formation. However, the association between H₂S and Lp‑PLA₂ expression levels with respect to foam cell formation has not yet been elucidated. The present study investigated whether H₂S can affect foam cell formation and potential signalling pathways via regulation of the expression and activity of Lp‑PLA₂. Using human monocytic THP‑1 cells as a model system, it was observed that oxidized low‑density lipoprotein (ox‑LDL) not only upregulates the expression level and activity of Lp‑PLA₂, it also downregulates the expression level and activity of Cystathionine γ lyase. Exogenous supplementation of H₂S decreased the expression and activity of Lp‑PLA₂ induced by ox‑LDL. Moreover, ox‑LDL induced the expression level and activity of Lp‑PLA₂ via activation of the p38MAPK signalling pathway. H₂S blocked the expression levels and activity of Lp‑PLA₂ induced by ox‑LDL via inhibition of the p38MAPK signalling pathway. Furthermore, H₂S inhibited Lp‑PLA₂ activity by blocking the p38MAPK signaling pathway and significantly decreased lipid accumulation in ox‑LDL‑induced macrophages, as detected by Oil Red O staining. The results of the present study indicated that H₂S inhibited ox‑LDL‑induced Lp‑PLA₂ expression levels and activity by blocking the p38MAPK signalling pathway, thereby improving foam cell formation. These findings may provide novel insights into the role of H₂S intervention in the progression of atherosclerosis.

Roles of Perivascular Adipose Tissue in Hypertension and Atherosclerosis

Significance: Perivascular adipose tissue (PVAT), which is present surrounding most blood vessels, from the aorta to the microvasculature of the dermis, is mainly composed of fat cells, fibroblasts, stem cells, mast cells, and nerve cells. Although the PVAT is objectively present, its physiological and pathological significance has long been ignored. Recent Advances: PVAT was considered as a supporting component of blood vessels and a protective cushion to the vessel wall from the neighboring tissues during relaxation and contraction. Nonetheless, further extensive research found that PVAT actively regulates blood vessel tone through PVAT-derived vasoactive factors, including both relaxing and contracting factors. In addition, PVAT contributes to atherosclerosis through paracrine secretion of a large number of bioactive factors such as adipokines and cytokines. Thereby, PVAT regulates the functions of blood vessels through various mechanisms operating directly on PVAT or on the underlying vessel layers, including vascular smooth muscle cells (VSMCs) and endothelial cells (ECs). Critical Issues: PVAT is a unique adipose tissue that plays an essential role in maintaining the vascular structure and regulating vascular function and homeostasis. This review focuses on recent updates on the various PVAT roles in hypertension and atherosclerosis. Future Directions: Future studies should further investigate the actual contribution of alterations in PVAT metabolism to the overall systemic outcomes of cardiovascular disease, which remains largely unknown. In addition, the messengers and underlying mechanisms responsible for the crosstalk between PVAT and ECs and VSMCs in the vascular wall should be systematically addressed, as well as the contributions of PVAT aging to vascular dysfunction.

The Role of Ubiquitin E3 Ligase in Atherosclerosis

Atherosclerosis is a chronic inflammatory vascular disease. Atherosclerotic cardiovascular disease is the main cause of death in both developed and developing countries. Many pathophysiological factors, including abnormal cholesterol metabolism, vascular inflammatory response, endothelial dysfunction and vascular smooth muscle cell proliferation and apoptosis, contribute to the development of atherosclerosis and the molecular mechanisms underlying the development of atherosclerosis are not fully understood. Ubiquitination is a multistep post-translational protein modification that participates in many important cellular processes. Emerging evidence suggests that ubiquitination plays important roles in the pathogenesis of atherosclerosis in many ways, including regulation of vascular inflammation, endothelial cell and vascular smooth muscle cell function, lipid metabolism and atherosclerotic plaque stability. This review summarizes important contributions of various E3 ligases to the development of atherosclerosis. Targeting ubiquitin E3 ligases may provide a novel strategy for the prevention of the progression of atherosclerosis.

Effects of gut microbiota on atherosclerosis through hydrogen sulfide

Cardiovascular diseases are the leading cause of death and morbidity worldwide. Atherosclerotic cardiovascular disease (ASCVD) is affected by both environmental and genetic factors. Microenvironmental disorders of the human gut flora are associated with a variety of health problems, not only gastrointestinal diseases, such as inflammatory bowel disease, but also extralintestinal organs. Hydrogen sulfide (H₂S) is the third gas signaling molecule other than nitric oxide and carbon monoxide. In the cardiovascular system, H₂S plays important roles in the regulation of blood pressure, angiogenesis, smooth muscle cell proliferation and apoptosis, anti-oxidative stress, cardiac functions. This review is aiming to explore the potential role of gut microbiota in the development of atherosclerosis through hydrogen sulfide production as a novel therapeutic direction for atherosclerosis.

Hydrogen Sulfide Switch Phenomenon Regulating Autophagy in Cardiovascular Diseases

Hydrogen sulfide (H₂S), a novel gaseous signaling molecule, is a vital physiological signal in mammals. H₂S protects the cardiovascular system via modulation of vasodilation, vascular remodeling, and inhibition of vascular calcification, and also has anti-atherosclerosis properties. Autophagy is a lysosomal-mediated intracellular degradation mechanism for excessive or abnormal proteins and lipids. The contribution of autophagy to normal and disease-state cell physiology is extremely complicated. Autophagy acts as a double-edged sword in the cardiovascular system. It can defend against damage to cells caused by environmental changes and it can also induce active cell death under certain conditions. In recent years, accumulating evidence indicates that H₂S can up- or downregulate autophagy in many pathological processes, thereby switching from a harmful to a beneficial role. In this review, we summarize progress on understanding the mechanism by which H₂S regulates autophagy in cardiovascular disease. We also discuss a H₂S switch phenomenon that regulates autophagy and provides protection in cardiovascular diseases.

Emerging roles of absent in melanoma 2 in cardiovascular diseases

Absent in melanoma 2 (AIM2) is a member of the PYHIN (pyrin and HIN domain-containing protein) family with important roles in sensing double-stranded DNA (dsDNA) and assembling the AIM2 inflammasome, which has wide-ranging, pro-inflammatory and pro-pyroptotic properties. The AIM2 inflammasome can become activated in atherosclerotic plaque, abdominal aortic aneurysm wall and injured myocardium, and its activation is tightly regulated by a variety of atherogenic factors. Activation of the AIM2 inflammasome has close links to the progression of several cardiovascular diseases. This review will summarize the current knowledge of AIM2 biology, providing the latest insights into the mechanisms and contributions of atherogenic factors to AIM2 inflammasome activation. In addition, we will also explore crosstalk between AIM2 and the pathologies of atherosclerosis, abdominal aortic aneurysm, myocardial infarction and heart failure. A better understanding of the pathological roles of AIM2 in these disorders will be helpful in developing novel therapeutic approaches.

Electrochemical Synthesis of Vinyl Sulfones by Sulfonylation of Styrenes with a Catalytic Amount of Potassium Iodide

An electrochemical sulfonylation reaction of styrenes was developed in which sodium arylsulfinates were used as sulfonylating reagents, a catalytic amount of KI was used as a redox mediator, and Bu4NBF4 was used as the electrolyte. In addition to various styrenes, sodium arylsulfinates with either electron-donating or electron-withdrawing groups were tolerated.

Enteral immunonutrition versus enteral nutrition for patients undergoing oesophagectomy: a systematic review and meta-analysis

OBJECTIVES

According to retrospective studies, oesophageal carcinoma is the second deadliest gastrointestinal cancer after gastric cancer. Enteral immunonutrition (EIN) has been increasingly used to enhance host immunity and relieve the inflammatory response of patients undergoing oesophagectomy; however, conclusions across studies remain unclear. We aimed to evaluate the effect of EIN on the clinical and immunological outcomes of patients undergoing oesophagectomy.

METHODS

Four electronic databases (MEDLINE, Embase, Web of Science and Cochrane Library) were used to search articles in peer-reviewed, English-language journals. The mean difference, relative risk or standard mean difference with 95% confidence interval were calculated. Heterogeneity was assessed by the Cochran's Q test and I2 statistic combined with the corresponding P-value. The analysis was carried out with RevMan 5.3.

RESULTS

Six articles were finally included, with a total of 320 patients with oesophageal cancer. The meta-analysis results showed that EIN did not improve clinical outcomes (such as infectious complications, pneumonia, surgical site infection, anastomotic leak and postoperative hospital stay) or immune indices [referring to C-reactive protein, interleukin (IL)-6, IL-8, tumour necrosis factor-α]. Descriptive analysis suggested that EIN also increased the serum concentrations of IgG and the percentage of the B-cell fraction. Thus, its impact on IL-8 and IL-6 remains inconsistent.

CONCLUSIONS

The early-stage impact of EIN on immunological status in patients undergoing oesophagectomy is still unclear. According to the results of this meta-analysis, whether EIN could improve the clinical outcomes or biological status after oesophagectomy compared to standard enteral nutrition is uncertain. Since the impact of EIN is unclear, current guidelines that strongly advise the use of EIN should be changed, as the utility of EIN is very uncertain. More appropriately powered clinical studies are warranted to confirm its effectiveness.

Macrophage polarization in atherosclerosis

Atherosclerosis is a chronic inflammatory response that increases the risk of cardiovascular diseases. An in-depth study of the pathogenesis of atherosclerosis is critical for the treatment of atherosclerotic cardiovascular disease. The development of atherosclerosis involves many cells, such as endothelial cells, vascular smooth muscle cells, macrophages, and others. The considerable effects of macrophages in atherosclerosis are inextricably linked to macrophage polarization and the resulting phenotype. Moreover, the significant impact of macrophages on atherosclerosis depend not only on the function of the different macrophage phenotypes but also on the relative ratio of different phenotypes in the plaque. Research on atherosclerosis therapy indicates that the reduced plaque size and enhanced stability are partly due to modulating macrophage polarization. Therefore, regulating macrophage polarization and changing the proportion of macrophage phenotypes in plaques is a new therapeutic approach for atherosclerosis. This review provides a new perspective for atherosclerosis therapy by summarizing the relationship between macrophage polarization and atherosclerosis, as well as treatment targeting macrophage polarization.

Effect of different therapeutic strategies on the clinical outcome of asymptomatic intralobar pulmonary sequestration

OBJECTIVES

Pulmonary sequestration is a rare congenital pulmonary malformation. The aim of this study was to explore the effect of different therapeutic strategies on the clinical outcome of asymptomatic intralobar pulmonary sequestration.

METHODS

We retrospectively reviewed the clinical data of 37 patients diagnosed with intralobar sequestration. All the patients were asymptomatic. Seventeen patients underwent video-assisted thoracoscopic surgery (VATS) once diagnosed and 20 patients chose to undergo observation. Of these 20 patients, 16 patients developed symptoms during the observation period and also underwent VATS; 4 patients never showed symptoms and did not have surgery. The 33 patients who had VATS were divided into 2 groups: group 1, patients who underwent VATS once diagnosed; group 2, patients who underwent VATS once symptoms appeared. Postoperative data and respiratory function data were compared between the 2 groups.

RESULTS

Twenty of the patients were men and 17 were women (mean age 37.05 ± 7.89 years). Results of a comparative analysis of the 2 groups indicated that patients in group 1 had better values for median estimated blood loss, median duration of chest tube insertion, postoperative hospital stay and postoperative hospital stay than those in group 2. Postoperative complications were reported in 1 patient in group 1 and in 3 patients in group 2. Meanwhile, the loss of lung function between group 1 and group 2 was statistically significant, which also suggested that patients benefited from surgery once diagnosed.

CONCLUSIONS

For asymptomatic intralobar sequestration, VATS could be effective and safe. The surgical intervention should be performed once the condition is diagnosed to avoid manifestations occurring and to preserve patients' quality of life.

The emerging roles of extracellular vesicles in diabetes and diabetic complications

Diabetes and diabetic vascular complications are now the leading cause of death in the world. The effects of traditional medical treatment are usually limited and accompanied by many side effects, such as hypoglycemia, obesity, liver and kidney damage, and gastrointestinal adverse reactions. Thus, it is urgent to explore some new strategies for the treatment of patients with diabetes. Recently, extracellular vesicles have received increased attention because of their emerging roles of cell-to-cell communication under physiological and pathological conditions. In addition, because of their abundant existence in almost all body fluids, as well as their plentiful cargos of bioactive proteins and miRNAs they carry, extracellular vesicles have a strong potential for therapeutic and diagnostic applications in many metabolic diseases, such as obesity and insulin resistance. Here, with the aim of providing the basis for the development of new treatments for diabetes, we review current understanding of extracellular vesicles and the critical roles it has played in the onset and progression of diabetes and diabetic complications.

Regulating the Warburg effect on metabolic stress and myocardial fibrosis remodeling and atrial intracardiac waveform activity induced by atrial fibrillation

Atrial fibrillation (AF) is associated with metabolic stress and induces myocardial fibrosis reconstruction by increasing glycolysis. One goal in the treatment of paroxysmal AF (p-AF) is to improve myocardial fibrosis reconstruction and myocardial metabolic stress caused by the Warburg effect. Adopted male canine that rapid right atrial pacing (RAP) for 6 days to establish a p-AF model. The canines were pre-treated with phenylephrine (PE) or dichloroacetic acid (DCA) before exposure to p-AF or non-p-AF. P-wave duration (P_max), minimum P-wave duration (P_min), P wave dispersion (PWD), atrial effective refractory period (AERP) and AERP dispersion (AERPd) were measured in canine atrial cardiomyocytes. Pyruvate dehydrogenase kinase-1 (PDK-1), PDK-4, lactate dehydrogenase A (LDHA), pyruvate dehydrogenase (PDH), citrate synthase (CS), isocitrate dehydrogenase (IDH), and matrix metalloproteinase 9 (MMP-9) were evaluated by western blotting and reverse transcription polymerase chain reaction (RT-PCR), content of adenosine monophosphate (AMP), adenosine triphosphate (ATP), lactic acid and glycogen, and activity of LDHA, PDK-1 and PDK-4 were evaluated by enzyme-linked immunosorbent assay (ELISA), myocardial tissue glycogen content was evaluated by PAS, myocardial fibrosis remodeling was evaluated by hematoxylin and eosin (H&E) and Masson staining. Our findings demonstrated that p-AF increases the Warburg effect-related metabolic stress and myocardial fibrosis remodeling by increasing the expression and activity of PDK-1, PDK-4, and LDHA, content of AMP and lactic acid, and the ratio of AMP/ATP and decreasing the expression of PDH, CS, and IDH, and glycogen content. In addition, p-AF can induce cardiomyocyte fibrosis remodeling and increase MMP-9 expression, and p-AF also increases atrial intracardiac waveform activity by prolonging P_max, P_min, PWD, and AERPd and shortening AERP. PDK isoforms agonists (PE) produce a similar p-AF pathological effect and can produce synergistic effects with p-AF, further increasing Warburg effect-related metabolic stress, myocardial fibrosis remodeling, and atrial intracardiac waveform activity. In contrast, the use of PDK-specific inhibitors (DCA) completely reverses these pathophysiological changes induced by p-AF. We demonstrate that p-AF can induce the Warburg effect in canine atrial cardiomyocytes and significantly improve p-AF-induced metabolic stress, myocardial fibrosis remodeling, and atrial intracardiac waveform activity by inhibiting the Warburg effect.

PCSK9: A new participant in lipophagy in regulating atherosclerosis?

Proprotein convertase subtilisin kexin 9 (PCSK9) regulates lipid metabolism by degrading low-density lipoprotein receptor on the surface of hepatocytes. PCSK9-mediated lipid degradation is associated with lipophagy. Lipophagy is a process by which autophagosomes selectively sequester lipid-droplet-stored lipids and are delivered to lysosomes for degradation. Lipophagy was first discovered in hepatocytes, and its occurrence provides important fundamental insights into how lipid metabolism regulates cellular physiology and pathophysiology. Furthermore, PCSK9 may regulate lipid levels by affecting lipophagy. This review will discuss recent advances by which PCSK9 mediates lipid degradation via the lipophagy pathway and present lipophagy as a potential therapeutic target for atherosclerosis.

Hydrogen sulfide inhibits PCSK9 expression through the PI3K/Akt‑SREBP‑2 signaling pathway to influence lipid metabolism in HepG2 cells

Hydrogen sulfide (H₂S) is an endogenous gaseous signaling molecule that plays important roles in the cardiovascular system. In our previous studies, we demonstrated that H₂S regulates lipid metabolism. In the present study, we aimed to explore the mechanisms through which H₂ regulates lipid metabolism in HepG2 cells in vitro. Treatment of the HepG2 cells with H₂S inhibited the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) and increased the level of low-density lipoprotein receptor (LDLR) in a time- and dose-dependent manner. The knockdown of PCSK9 by siRNA effectively increased the levels of LDLR and 1,1′-dioctadecyl-3,3,3′,3′-tetramethyl-indocarbocyanine perchlorate-labeled LDL (DiI-LDL) uptake in the H₂S-treated HepG2 cells. Furthermore, the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)-sterol regulatory element binding proteins 2 (SREBP-2) signaling pathway was confirmed to be involved in H₂S-regulated PCSK9 expression. Notably, the HepG2 cells were incubated with 30% serum and DiI-LDL for 24 h, and the results revealed that H₂S increased lipid uptake, but caused no increase in lipid accumulation. On the whole, the findings of this study demonstrate that H₂S is involved in the regulation of lipid metabolism in HepG2 cells through the regulation of the expression of PCSK9 via the PI3K/Akt-SREBP-2 signaling pathway. To the very best of our knowledge, this study is the first to report that H₂S can regulate the expression of PCSK9.

Tissue factor pathway inhibitor in atherosclerosis

Tissue factor pathway inhibitor (TFPI) reduces the development of atherosclerosis by regulating tissue factor (TF) mediated coagulation pathway. In this review, we focus on recent findings on the inhibitory effects of TFPI on endothelial cell activation, vascular smooth muscle cell (VSMC) proliferation and migration, inflammatory cell recruitment and extracellular matrix which are associated with the development of atherosclerosis. Meanwhile, we are also concerned about the impact of TFPI levels and genetic polymorphisms on clinical atherogenesis. This article aims to explain the mechanism in inhibiting the development of atherosclerosis and clinical effects of TFPI, and provide new ideas for the clinical researches and mechanism studies of atherothrombosis.

Fibroblast growth factor-21 alleviates hypoxia/reoxygenation injury in H9c2 cardiomyocytes by promoting autophagic flux

Fibroblast growth factor (FGF)-21, a member of the family of FGFs, exhibits protective effects against myocardial ischemia and ischemia/reperfusion injury; it is also an enhancer of autophagy. However, the mechanisms underlying the protective role of FGF-21 against cardiomyocyte hypoxia/reoxygenation (H/R) injury remain unclear. The present study aimed to investigate the effect of FGF-21 on H9c2 cardiomyocyte injury induced by H/R and the mechanism associated with changes in autophagy. Cultured H9c2 cardiomyocytes subjected to hypoxia were treated with a vehicle or FGF-21 during reoxygenation. The viability of H9c2 rat cardiomyocytes was measured using Cell Counting Kit-8 and trypan blue exclusion assays. The contents of creatine kinase (CK) and creatine kinase isoenzymes (CK-MB), cardiac troponin I (cTnT), cardiac troponin T (cTnI) and lactate dehydrogenase (LDH) in culture medium were detected with a CK, CK-MB, cTnT, cTnI and LDH assay kits. The protein levels were examined by western blot analysis. Autophagic flux was detected by Ad-mCherry-GFP-LC3B autophagy fluorescent adenovirus reagent. The results indicated that FGF-21 alleviated H/R-induced H9c2 myocardial cell injury and enhanced autophagic flux during H/R, and that this effect was antagonized by co-treatment with 3-methyladenine, an autophagy inhibitor. Furthermore, FGF-21 increased the expression levels of Beclin-1 and Vps34 proteins, but not of mechanistic target of rapamycin. These data indicate that FGF-21 treatment limited H/R injury in H9c2 cardiomyocytes by promoting autophagic flux through upregulation of the expression levels of Beclin-1 and Vps34 proteins.

Endothelial to mesenchymal transition in atherosclerotic vascular remodeling

Endothelial cells are the main components of the heart, blood vessels, and lymphatic vessels, which play an important role in regulating the physiological functions of the cardiovascular system. Endothelial dysfunction is involved in a variety of acute and chronic cardiovascular diseases. As a special type of epithelial-mesenchymal transition (EMT), endothelium to mesenchymal transition (EndMT) regulates the transformation of endothelial cells into mesenchymal cells accompanied by changes in the expression of various transcription factors and cytokines, which is closely related to vascular endothelial injury, vascular remodeling, myocardial fibrosis and valvar disease. Endothelial cells undergoing EndMT lose their endothelial characteristics and undergo a transition toward a more mesenchymal-like phenotype. However, the molecular mechanism of EndMT remains unclear. EndMT, as a type of endothelial dysfunction, can cause vascular remodeling which is a major determinant of atherosclerotic luminal area. Therefore, exploring the important signaling pathways in the process of EndMT may provide novel therapeutic strategies for treating atherosclerotic diseases.

Perivascular adipose tissue (PVAT) in atherosclerosis: a double-edged sword

Perivascular adipose tissue (PVAT), the adipose tissue that surrounds most of the vasculature, has emerged as an active component of the blood vessel wall regulating vascular homeostasis and affecting the pathogenesis of atherosclerosis. Although PVAT characteristics resemble both brown and white adipose tissues, recent evidence suggests that PVAT develops from its own distinct precursors implying a closer link between PVAT and vascular system. Under physiological conditions, PVAT has potent anti-atherogenic properties mediated by its ability to secrete various biologically active factors that induce non-shivering thermogenesis and metabolize fatty acids. In contrast, under pathological conditions (mainly obesity), PVAT becomes dysfunctional, loses its thermogenic capacity and secretes pro-inflammatory adipokines that induce endothelial dysfunction and infiltration of inflammatory cells, promoting atherosclerosis development. Since PVAT plays crucial roles in regulating key steps of atherosclerosis development, it may constitute a novel therapeutic target for the prevention and treatment of atherosclerosis. Here, we review the current literature regarding the roles of PVAT in the pathogenesis of atherosclerosis.

PCSK9: A novel inflammation modulator in atherosclerosis?

Proprotein convertase subtilisin/kexin 9 (PCSK9) is the ninth member of the secretory serine protease family. It binds to low-density lipoprotein receptor (LDLR) for endocytosis and lysosome degradation in the liver, resulting in an increasing in circulating LDL-cholesterol (LDL-c) level. Since a PCSK9 induced increase in plasma LDL-c contributes to atherosclerosis, PCSK9 inhibition has become a new strategy in preventing and treating atherosclerosis. However, in addition to the effect of PCSK9 on elevating blood LDL-c levels, accumulating evidence shows that PCSK9 plays an important role in inflammation, likely representing another major mechanism for PCSK9 to promote atherosclerosis. In this review, we discuss the association of PCSK9 and inflammation, and highlight the specific effects of PCSK9 on different vascular cellular components involved in the atherosclerotic inflammation. We also discuss the clinical evidence for the association between PCSK9 and inflammation in atherosclerotic cardiovascular disease. A better understanding of the direct association of PCSK9 with atherosclerotic inflammation might help establish a new role for PCSK9 in vascular biology and identify a novel molecular mechanism for PCSK9 therapy.

Role of PCSK9 in lipid metabolism and atherosclerosis

Elevated plasma low-density lipoprotein cholesterol (LDL-C) is an important risk factor for cardiovascular diseases. Statins are the most widely used therapy for patients with hyperlipidemia. However, a significant residual cardiovascular risk remains in some patients even after maximally tolerated statin therapy. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a new pharmacologically therapeutic target for decreasing LDL-C. PCSK9 reduces LDL intake from circulation by enhancing LDLR degradation and preventing LDLR recirculation to the cell surface. Moreover, PCSK9 inhibitors have been approved for patients with either familial hypercholesterolemia or atherosclerotic cardiovascular disease, who require additional reduction of LDL-C. In addition, PCSK9 inhibition combined with statins has been used as a new approach to help reduce LDL-C levels in patients with either statin intolerance or unattainable LDL goal. This review will discuss the emerging anti-PCSK9 therapies in the regulation of cholesterol metabolism and atherosclerosis.

PCSK9: A potential regulator of apoE/apoER2 against inflammation in atherosclerosis?

Atherosclerosis is characterized by chronic inflammation and lipid accumulation in arterial walls, resulting in several vascular events. Proprotein convertase subtilisin kexin 9 (PCSK9), a serine protease, has a pivotal role in the degradation of hepatic low-density lipoprotein receptor (LDLR). It can increase plasma concentrations of low-density lipoprotein cholesterol and affect lipid metabolism. Recently, PCSK9 has been found to accelerate atherosclerosis via mechanisms apart from that involving the degradation of LDLR, with an emerging role in regulating the inflammatory response in atherosclerosis. Apolipoprotein E receptor 2 (apoER2), one of the LDLR family members expressed in macrophages, can bind to its ligand apolipoprotein E (apoE), exhibiting an anti-inflammatory role in atherosclerosis. Evidence suggests that apoER2 is a target of PCSK9. This review aims to discuss PCSK9 as a potential regulator of apoE/apoER2 against inflammation in atherosclerosis.

Tet methylcytosine dioxygenase 2 inhibits atherosclerosis via upregulation of autophagy in ApoE-/- mice

Tet methylcytosine dioxygenase 2 (TET2) mediates the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). The loss of TET2 is associated with advanced atherosclerotic lesions. Our previous study showed that TET2 improves endothelial cell function by enhancing endothelial cell autophagy. Accordingly, this study determined the role of TET2 in atherosclerosis and potential mechanisms. In ApoE-/- mice fed high-fat diet, TET2 overexpression markedly decreased atherosclerotic lesions with uniformly increased level of 5hmC and decreased level of 5mC in genomic DNA. TET2 overexpression also promoted autophagy and downregulated inflammation factors, such as vascular cell adhesion molecule 1, intercellular adhesion molecule 1, monocyte chemotactic protein 1, and interleukin-1. Consistently, TET2 knockdown with small hairpin RNA (shRNA) in ApoE-/- mice decreased 5hmC and increased 5mC levels in atherosclerotic lesions. Meanwhile, autophagy was inhibited and atherosclerotic lesions progressed with an unstable lesion phenotype characterized by large lipid core, macrophage accumulation, and upregulated inflammation factor expression. Experiments with the cultured endothelial cells revealed that oxidized low-density lipoprotein (ox-LDL) inhibited endothelial cell autophagy. TET2 shRNA strengthened impaired autophagy and autophagic flux in the ox-LDL-treated endothelial cells. TET2 overexpression reversed these effects by decreasing the methylation level of the Beclin 1 promoter, which contributed to the downregulation of inflammation factors. Overall, we identified that TET2 was downregulated during the pathogenesis of atherosclerosis. The downregulation of TET2 promotes the methylation of the Beclin 1 promoter, leading to endothelial cell autophagy, impaired autophagic flux, and inflammatory factor upregulation. Upregulation of TET2 may be a novel therapeutic strategy for treating atherosclerosis.

miR-23b-3p and miR-125b-5p downregulate apo(a) expression by targeting Ets1 in HepG2 cells

High concentrations of plasma lipoprotein(a) [Lp(a)] have been inferred to be an independent risk factor for cardiovascular and cerebrovascular diseases, such as coronary artery diseases, restenosis, and stroke. Apolipoprotein(a) [apo(a)] is one of the most important components of Lp(a) and contributes greatly to the increased concentration of plasma Lp(a). As a critical positive transacting factor of apo(a) gene, Ets1 has been proven as a target gene of several miRNAs, such as miR-193b, miR-125b-5p, miR-200b, miR-1, and miR-499. In this study, a series of experiments on miRNAs and relative miRNAs inhibitor delivered HepG2 cells were conducted, and two miRNAs that downregulate the apo(a) by targeting the 3'-UTR of Ets1 were identified. Results showed that apo(a) and Ets1 were differentially expressed in SMMC7721 and HepG2 cell lines. Meanwhile, apo(a) and Ets1 were inversely correlated with several hepatic endogenous miRNAs, such as miR-125b-5p, miR-23b-3p, miR-26a-5p, and miR-423-5p, which were predicted to bind to Ets1. Results show that miR-125b-5p and miR-23b-3p mimics could inhibit the synthesis of apo(a) by directly targeting Ets1 in HepG2, thereby reducing the plasma Lp (a) concentration.