Comparison of Drug-Coated Balloon and Drug-Eluting Stent for the Treatment of Small Vessel Disease (from the Dissolve SVD Randomized Trial).

The Dissolve drug-coated balloons (DCBs) is a new-generation DCB coated with paclitaxel of balloon surface, with midchain triglyceride excipient. Although the use of DCBs is a promising technique, little is known about the the clinical efficacy of the novel Dissolve DCB in coronary small vessel disease. This study was a prospective, randomized, multicenter, noninferiority trial comparing the Dissolve DCB with the Resolute drug-eluting stent (DES) in patients with a reference vessel diameter ≥2.25 and ≤2.75 mm. Patients with a reference vessel diameter ≥2.00 and <2.25 mm were enrolled in the very small vessel registry. The angiographic and clinical follow-up were planned at 9 months and 1 year in all patients, respectively. The primary end point was 9-month in-segment percentage diameter stenosis. A total of 247 patients with small vessel disease from 10 Chinese sites were included (Dissolve DCB, n = 118; Resolute DES, n = 129); 30 patients were treated with the DCB in the very small vessel cohort. The 9-month in-segment percentage diameter stenosis was 31.2 ± 2.0% with Dissolve DCB versus 26.1 ± 2.1% with Resolute DES; the 1-sided 97.5% upper confidence limit of the difference was 10.3% (p for noninferiority = 0.0002). At 12 months, the DCB and DES groups were associated with similar rates of target lesion failure (8.5% vs 6.1%, p = 0.28) and major adverse cardiac and cerebrovascular events (20.9% vs 13.6%, p = 0.12). In conclusion, the Dissolve DCB was noninferior to the Resolute DES for the primary end point of 9-month in-segment percentage diameter stenosis in this multicenter, head-to-head, randomized trial (a safety and efficacy study of Dissolve In Treatment Of Coronary Small Vessel Disease; NCT03376646).

Latency-associated peptide (LAP)+CD4+ regulatory T cells prevent atherosclerosis by modulating macrophage polarization.

RATIONALE: A persistent autoimmune and inflammatory response plays a critical role in the progression of atherosclerosis. The transcription factor forkhead box P3 (Foxp3)+CD4+ regulatory T cells (Foxp3+ Tregs) attenuate atherosclerosis. Latency-associated peptide (LAP)+CD4+ T cells are a new class of Tregs whose role in atherosclerosis is unknown. OBJECTIVE: To investigate the function of CD4+LAP+ Tregs in inhibiting inflammation and preventing atherosclerosis. METHODS AND RESULTS: Depletion of CD4+LAP+ Tregs results in aggravated inflammation and atherosclerotic lesions. Mechanistically, CD4+LAP+ Treg depletion was associated with decreased M2-like macrophages and increased Th1 and Th17 cells, characterized by increased unstable plaque promotion and decreased expression of inflammation-resolving factors in both arteries and immune organs. In contrast, adoptive transfer of CD4+LAP+ Tregs to ApoE-/- mice or CD4-/-ApoE-/- mice led to decreased atherosclerotic lesions. Compared with control animals, adoptive transfer of CD4+LAP+ Tregs induced M2-like macrophage differentiation within the atherosclerotic lesion and spleen, associated with increased collagen and α-SMA in plaques and decreased expression of MMP-2 and MMP-9. Mechanistic studies reveal that isolated CD4+LAP+ Tregs exhibit a tolerance phenotype, with increased expression of inhibitory cytokines and coinhibitory molecules. After coculture with CD4+LAP+ Tregs, monocytes/macrophages display typical features of M2 macrophages, including upregulated expression of CD206 and Arg-1 and decreased production of MCP-1, IL-6, IL-1ß and TNF-α, which was almost abrogated by transwell and partially TGF-ß1 neutralization. RNA-seq analysis showed different gene expression profiles between CD4+LAP+ Tregs and LAP-CD4+ T cells and between CD4+LAP+ Tregs of ApoE-/- mice and CD4+LAP+ Tregs of C57BL/6 mice, of which Fancd2 and IL4i1 may contribute to the powerful inhibitory properties of CD4+LAP+ Tregs. Furthermore, the number and the suppressive properties of CD4+LAP+ Tregs were impaired by oxLDL. CONCLUSIONS: Our data indicate that the remaining CD4+LAP+ Tregs play a protective role in atherosclerosis by modulating monocyte/macrophage differentiation and regulatory factors, which may partly explain the protective effect of T cells tolerance in atherosclerosis. Moreover, adoptive transfer of CD4+LAP+ Tregs constitutes a novel approach to treat atherosclerosis.

Case report: Malignant vasovagal reflex syndrome during percutaneous transcatheter closure of patent foramen ovale.

Malignant vasovagal reflex syndrome can be induced by pulling of cardiac tissue during percutaneous transcatheter closure of patent foramen ovale. In this case, a patient presented with a malignant vasovagal reflex syndrome characterized by decreased heart rate, cardiac arrest, and ventricular tachycardia. Therefore, it's particularly important to observe patients' heart rate and timely deal with vasovagal reflex syndrome during the operation.

A Randomized Comparison of 2 Different Drug-Coated Balloons for In-Stent Restenosis.

BACKGROUND: Although use of drug-coated balloons (DCB) is a promising technique, little is known about the clinical efficacy of the Dissolve DCB in drug-eluting stent (DES) in-stent restenosis (ISR). OBJECTIVES: This study sought to evaluate the efficacy and safety of the Dissolve DCB in patients with DES ISR. METHODS: This was a prospective, multicenter, randomized, noninferiority trial comparing Dissolve DCB with SeQuent Please DCB in patients with DES ISR. Angiographic and clinical follow-up was planned at 9 months in all patients. The primary endpoint was 9-month in-segment late loss. RESULTS: A total of 260 patients with ISR from 10 Chinese sites were included (Dissolve DCB, n = 128; SeQuent Please DCB, n = 132). Nine-month in-segment late loss was 0.50 ± 0.06 mm with Dissolve DCB vs 0.47 ± 0.07 mm with SeQuent Please DCB; the 1-sided 97.5% upper confidence limit of the difference was 0.18 mm (P for noninferiority = 0.03). Rates of target lesion failure and binary restenosis were numerical higher in the Dissolve DCB cohort compared with the SeQuent Please DCB cohort at 9 months (17.5% vs 10.7%; P = 0.12; 23.4% vs 16.4%; P = 0.19, respectively). At 9 months, major adverse cardiac and cerebrovascular events occurred in 36 patients (28.3%) vs 30 patients (22.9%) in the Dissolve DCB and SeQuent Please DCB groups, respectively. CONCLUSIONS: In this head-to-head randomized trial, the Dissolve DCB was noninferior to the SeQuent Please DCB for 9-month in-segment late loss. However, Dissolve DCB with its numerical increase in target lesion failure and binary restenosis warrants assessment in larger clinical trials (A Safety and Efficacy Study of Dissolve™ in Treatment of Coronary In-Stent Restenosis; NCT03373695).

Ablation of CXCR4 expression in cardiomyocytes exacerbates isoproterenol­induced cell death and heart failure.

CXCR4 is a seven­transmembrane­spanning Gi­coupled receptor for the SDF­1 chemokine and plays a critical role in cardiovascular development and post­injury repair. However, the specific role of CXCR4 in cardiomyocytes is incompletely understood. It was hypothesized that CXCR4 activation in cardiomyocytes antagonizes ß­adrenoceptor/Gs signaling­induced cardiac dysfunction. Cardiomyocyte­specific CXCR4 knockout (CXCR4­CMKO) mice were generated by crossing CXCR4fl/fl and MHC­Cre+/­ mice. Their cardiac structure and function in the basal state are equivalent to that of the control MHC­Cre+/­ littermates until at least 4 months old. However, following continuous subcutaneous administration of isoproterenol (Iso) via an osmotic mini­pump, the ventricular myocardial contractility, dilation, cardiomyocyte apoptosis, and interstitial fibrosis are worse in CXCR4­CMKO mice than in MHC­Cre+/­ littermates. In the cultured H9C2 cardiomyocytes, SDF­1 treatment markedly attenuated Iso­induced apoptosis and reduction in phospho­Akt, and this protective effect was lost by knockdown of CXCR4 or by co­treatment with Gi inhibitors. In conclusion, CXCR4 promotes cardiomyocyte survival and heart function during ß­adrenergic stress.

Interleukin-27 Ameliorates Atherosclerosis in ApoE-/- Mice through Regulatory T Cell Augmentation and Dendritic Cell Tolerance.

Atherosclerosis, which is characterized by chronic inflammation in the arterial wall, is driven by immune cells and cytokines. Recent evidence indicated that interleukin (IL)-27 showed pleiotropic properties in immune diseases. However, precise mechanisms of IL-27, especially in atherosclerosis remains unknown. In our research, we examined the influence of the administration of IL-27 and an anti-IL-27p28 antibody (anti-IL-27p28-Ab) on both the initiation and the progression of atherosclerosis. In the groups (both the initiation and the progression) receiving recombinant IL-27 administration, the formation of atherosclerotic plaques was suspended, and the percentage of regulatory T cells (LAP+ or Foxp3+) in the spleen and peripheral blood was increased. Meanwhile, the number of T helper 1 (Th1) and T helper 17 (Th17) cells was decreased. In the peripheral blood plasma, TGF-ß and IL-10 expression were increased, while the levels of IFN-γ and IL-17 were reduced. As for lesions, the mRNA expression of Foxp3, TGF-ß, and IL-10 was increased, while that of IFN-γ and IL-17 was reduced. In the anti-IL-27p28 antibody groups, we obtained opposite results. We also observed that DCs treated with IL-27 display a tolerogenic phenotype and that IL-27-treated tolerogenic DCs (tDCs) are likely to play a protective role during atherosclerosis. Our study indicates that IL-27 or adoptive transfer of IL-27 loaded tDCs may be a new therapeutic approach in atherosclerosis.

Prevalence and prognosis of molecularly defined familial hypercholesterolemia in patients with acute coronary syndrome.

Background: Familial hypercholesterolemia (FH) can elevate serum low-density lipoprotein cholesterol (LDL-C) levels, which can promote the progression of acute coronary syndrome (ACS). However, the effect of FH on the prognosis of ACS remains unclear. Methods: In this prospective cohort study, 223 patients with ACS having LDL-C ≥ 135.3 mg/dL (3.5 mmol/L) were enrolled and screened for FH using a multiple-gene FH panel. The diagnosis of FH was defined according to the ACMG/AMP criteria as carrying pathogenic or likely pathogenic variants. The clinical features of FH and the relationship of FH to the average 16.6-month risk of cardiovascular events (CVEs) were assessed. Results: The prevalence of molecularly defined FH in enrolled patients was 26.9%, and coronary artery lesions were more severe in patients with FH than in those without (Gensini score 66.0 vs. 28.0, respectively; P < 0.001). After lipid lowering, patients with FH still had significantly higher LDL-C levels at their last visit (73.5 ± 25.9 mg/dL vs. 84.7 ± 37.1 mg/dL; P = 0.013) compared with those without. FH increased the incidence of CVEs in patients with ACS [hazard ratio (HR): 3.058; 95% confidence interval (CI): 1.585-5.900; log-rank P < 0.001]. Conclusion: FH is associated with an increased risk of CVEs in ACS and is an independent risk factor for ACS. This study highlights the importance of genetic testing of FH-related gene mutations in patients with ACS.

IL-37 Expression in Patients with Abdominal Aortic Aneurysm and Its Role in the Necroptosis of Vascular Smooth Muscle Cells.

Background: Our previous studies have shown that interleukin- (IL-) 37 plays a protective role in patients and animal models with coronary artery disease. However, the role of IL-37 in patients with abdominal aortic aneurysm (AAA), another artery disease, is yet to be elucidated. Methods and Results: AAA tissues and plasma samples were obtained from patients with or without surgical intervention. Normal renal aortic tissues were collected from kidney transplant donors. Our findings established that in AAA, IL-37 was distributed in endothelial cells, macrophages, and vascular smooth muscle cells (VSMCs) and that it was chiefly concentrated in VSMCs. Furthermore, the expression was found to be downregulated compared with that in normal artery tissues. Immunofluorescence showed that, unlike normal arteries, IL-37 was translocated to the nucleus of VSMCs in AAA. Moreover, in patients with AAA, the expressions of IL-37, IL-6, and tumor necrosis factor- (TNF-) α were increased in the plasma in comparison with the healthy controls. Correlation analysis revealed that IL-37 was positively correlated with IL-6, TNF-α, age, aneurysm diameter, and blood pressure. Furthermore, human aortic vascular smooth muscle cells (HASMCs) were stimulated with angiotensin II (AngII) in vitro to simulate smooth muscle cell (SMC) damage in AAA. A decrease in IL-37 expression and an increase in receptor-interacting serine/threonine-protein kinase 3 (RIPK3) expression were observed in HASMCs stimulated with AngII. On this basis, inhibition of RIPK3 with GSK'872 significantly attenuated necroptosis. Moreover, the necroptosis rates were significantly lowered in HASMCs treated with recombinant IL-37, whereas the rates were enhanced when the cells were depleted of the interleukin. Immunoblotting results showed that both exogenous and endogenous IL-37 could affect the expressions of RIPK3, NLRP3, and IL-1ß. Also, the phosphorylation of RIPK3 and p65 was affected. Meanwhile, IL-37 promoted the transition of SMC from proliferative type to contractile type. Conclusions: The expression of IL-37 in VSMCs decreases in patients with AAA, whereas IL-37 supplementation suppresses RIPK3-mediated necroptosis and promotes the transition of VSMCs from proliferative to contractile type.

Effects of IL-38 on Macrophages and Myocardial Ischemic Injury.

Macrophages play an important role in clearing necrotic myocardial tissues, myocardial ischemia-reperfusion injury, and ventricular remodeling after myocardial infarction. M1 macrophages not only participate in the inflammatory response in myocardial tissues after infarction, which causes heart damage, but also exert a protective effect on the heart during ischemia. In contrast, M2 macrophages exhibit anti-inflammatory and tissue repair properties by inducing the production of high levels of anti-inflammatory cytokines and fibro-progenitor cells. Interleukin (IL)-38, a new member of the IL-1 family, has been reported to modulate the IL-36 signaling pathway by playing a role similar to that of the IL-36 receptor antagonist, which also affects the production and secretion of macrophage-related inflammatory factors that play an anti-inflammatory role. IL-38 can relieve myocardial ischemia-reperfusion injury by promoting the differentiation of M1 macrophages into M2 macrophages, inhibit the activation of NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome, and increase the secretion of anti-inflammatory cytokines, such as IL-10 and transforming growth factor-ß. The intact recombinant IL-38 can also bind to interleukin 1 receptor accessory protein-like 1 (IL-1RAPL1) to activate the c-jun N-terminal kinase/activator protein 1 (JNK/AP1) pathway and increase the production of IL-6. In addition, IL-38 regulates dendritic cell-induced cardiac regulatory T cells, thereby regulating macrophage polarization and improving ventricular remodeling after myocardial infarction. Accordingly, we speculated that IL-38 and macrophage regulation may be therapeutic targets for ameliorating myocardial ischemic injury and ventricular remodeling after myocardial infarction. However, the specific mechanism of the IL-38 action warrants further investigation.

Role of IL-37- and IL-37-Treated Dendritic Cells in Acute Coronary Syndrome.

As a chronic inflammatory disease, atherosclerosis is a leading cause of morbidity and mortality in most countries. Inflammation is responsible for plaque instability and the subsequent onset of acute coronary syndrome (ACS), which is one of the leading causes of hospitalization. Therefore, exploring the potential mechanism underlying ACS is of considerable concern, and searching for alternative therapeutic targets is very urgent. Interleukin-37 (IL-37) inhibits the production of proinflammatory chemokines and cytokines and acts as a natural inhibitor of innate and adaptive immunity. Interestingly, our previous study with murine models showed that IL-37 alleviated cardiac remodeling and myocardial ischemia/reperfusion injury. Of note, our clinical study revealed that IL-37 is elevated and plays a beneficial role in patients with ACS. Moreover, dendritic cells (DCs) orchestrate both immunity and tolerance, and tolerogenic DCs (tDCs) are characterized by more secretion of immunosuppressive cytokines. As expected, IL-37-treated DCs are tolerogenic. Hence, we speculate that IL-37- or IL-37-treated DCs is a novel therapeutic possibility for ACS, and the precise mechanism of IL-37 requires further study.

GARP and GARP-Treated tDC Prevented the Formation of Atherosclerotic Plaques in ApoE-/- Mice.

PURPOSE: This study aims to clarify the specific mechanism by which GARP affects the atherosclerotic plaques in ApoE-/- mice and the effect of GARP-tDC on atherosclerosis. METHODS: The mice were randomly divided into three groups: the control group, the GARP-overexpressed group and the GARP-inhibited group. After 12 weeks, all the mice were euthanized, and the specimens were collected. In vitro, experiments were conducted to observe the effect of GARP on DC phenotype and the changes of the proportion of CD4+CD25+Foxp3+ Treg cells when GARP-tDCs were co-cultured with CD4+ T cells. Furthermore, adoptive transmission of GARP-tDCs was used to observe the effect on atherosclerotic plaque in mice. RESULTS: The GARP-overexpressed group enhanced the biological activity of Foxp3+ CD4+CD25+ Tregs and resulted in increased expression of LAP in T cells. In addition, the GARP-overexpressed group significantly suppressed the function of Th1 and Th17, and decreased the secretion of INF-γ and IL-17A. Thus, GARP had a protective effect on atherosclerosis. In vitro, we found that GARP-tDC had a tolerance-inducing phenotype, and GARP-tDC also had the ability to induce tolerance when co-cultured with CD4+ T cells. More importantly, adoptive transmission of GARP-tDCs reduced the size of atherosclerotic plaques. CONCLUSION: GARP and the GARP-tDC play protective roles in atherosclerosis. The protective effect of GARP on atherosclerosis is achieved by increasing CD4+CD25+Foxp3+ Treg cells and inhibiting the production of IFN-γ and IL-17A.

Corrigendum: Galectin-9: A Suppressor of Atherosclerosis?

[This corrects the article DOI: 10.3389/fimmu.2020.604265.].

Phosphorylcholine-Primed Dendritic Cells Aggravate the Development of Atherosclerosis in ApoE-/- Mice.

Background: Atherosclerosis is an inflammatory disease involving activation of adaptive and innate immune responses to antigens, including oxidized low-density lipoprotein (oxLDL) and phosphorylcholine (PC). Dendritic cells (DCs), which are antigen-presenting cells that activate T cells, are present in atherosclerotic lesions and are activated in immune organs. However, the mechanism by which PC promotes atherosclerosis is unclear. Methods and Results: To evaluate whether PC promotes atherosclerosis via DCs, 2×105 DCs activated by PC-keyhole limpet hemocyanin (DCs+PC-KLH) were injected into ApoE-/- mice and the features of the plaques and the effects of the DCs on cellular and humoral immunity against PC-KLH were determined. Mice injected with DCs+PC-KLH had significantly larger atherosclerotic lesions than controls, with increased inflammation in the lesions and plaque instability. Furthermore, DCs+PC-KLH were characterized using flow cytometry after coculture of bone marrow-derived DCs and naïve T cells. DCs+PC-KLH showed an inflammatory phenotype, with increased CD86, CD40, and major histocompatibility complex Class II molecules (MHC-II), which promoted PC-specific T helper (Th) 1 and Th17 cell differentiation in vivo and in vitro. Moreover, 2 weeks after the administration of DCs+PC-KLH to mice, these mice produced PC- and oxLDL-specific IgG2a, compared with no production in the controls. Conclusions: These findings suggest that DCs presenting PC promote specific immunity to PC, increase lesion inflammation, and accelerate atherosclerosis, which may explain how PC promotes atherosclerosis.

Galectin-9: A Suppressor of Atherosclerosis?

It is no longer controversial that atherosclerosis is a vascular wall chronic inflammatory disease mediated by cells of innate and adaptive immunity. Galectin-9 (Gal-9) seems to be a crucial regulator of T-cell immunity by inducing apoptosis in specific T-cell subpopulations associated with autoimmunity and inflammatory disease. Accumulating evidence showed that galectin-9 signaling via T-cell immunoglobulin mucin 3 (TIM-3) is concerned with different regulatory functions in autoimmunity, including direct depletion of pro-inflammatory T-cells, expanding the number of regulatory T cells, altering macrophages to an anti-inflammatory state and the induction of repressive myeloid-derived suppressor cells. In addition, anti-Tim-3-Ab administration increased atherosclerotic plaque formation by blocking Tim-3-galectin-9 interaction. Hence, we hypothesize that galectin-9 may be a novel therapy for atherosclerotic disease. Further researches are needed to investigate the precise effect of galectin-9 in the process of atherosclerosis.

Down-regulation and Clinical Implication of Galectin-9 Levels in Patients with Acute Coronary Syndrome and Chronic Kidney Disease.

In various autoimmune diseases, Galecin-9 (Gal-9) has been shown to regulate the T-cell balance by decreasing Th1 and Th17, while increasing the number of regulatory T cells (Tregs). However, the role of Gal-9 in the patients with acute coronary syndrome (ACS) and chronic kidney disease (CKD) remains unclear. This study aims to measure the Gal-9 levels in serum and peripheral blood mononuclear cells (PBMCs) in patients with ACS plus CKD and examine their clinical implication. The serum levels of Gal-9 were determined by enzyme-linked immunosorbent assay (ELISA), the expression levels of Gal-9, Tim-3, and Foxp3 mRNA in PBMCs were detected by real-time reverse transcription-polymerase chain reaction (RT-PCR), and the expression of Gal-9 on the surface of PBMCs and in PBMCs was analyzed by flow cytometry. Furthermore, the correlation of serum Gal-9 levels with anthropometric and biochemical variables in patients with ACS plus CKD was analyzed. The lowest levels of Gal-9 in serum and PBMCs were found in the only ACS group, followed by the ACS+CKD group, and the normal coronary artery (NCA) group, respectively. Serum Gal-9 levels were increased along with the progression of glomerular filtration rate (GFR) categories of G1 to G4. Additionally, serum Gal-9 levels were negatively correlated with high-sensitivity C-reactive protein (hs-CRP), estimated GFR (eGFR), and lipoprotein(a), but positively with creatinine, age, osmotic pressure, and blood urea nitrogen (BUN). Notably, serum Gal-9 was independently associated with hs-CRP, osmotic pressure, and lipoprotein(a). Furthermore, serum Gal-9 levels were elevated in patients with type 2 diabetes (T2DM) and impaired glucose tolerance (IGT) in ACS group. It was suggested that the levels of Gal-9 in serum and PBMCs were decreased in patients with simple ACS and those with ACS plus CKD, and hs-CRP, eGFR, osmotic pressure and T2DM may have an influence on serum Gal-9 levels.

Clinical Characteristics and Prognosis of 244 Cardiovascular Patients Suffering From Coronavirus Disease in Wuhan, China.

Background The coronavirus disease 2019 (COVID-19) has developed into a global outbreak. Patients with cardiovascular disease (CVD) with COVID-19 have different clinical characteristics and prognostic outcomes. This study aimed to summarize the clinical characteristics and laboratory indicators of patients with COVID-19 with CVD, especially the critically ill patients. Methods and Results This study included 244 patients diagnosed with COVID-19 and CVD (hypertension, coronary heart disease, or heart failure). The patients were categorized into critical (n=36) and noncritical (n=208) groups according to the interim guidance of China's National Health Commission. Clinical, laboratory, and outcome data were collected from the patients' medical records and compared between the 2 groups. The average body mass index of patients was significantly higher in the critical group than in the noncritical group. Neutrophil/lymphocyte ratio, and C-reactive protein, procalcitonin, and fibrinogen, and d-dimer levels at admission were significantly increased in the critical group. The all-cause mortality rate among cases of COVID-19 combined with CVD was 19.26%; the proportion of coronary heart disease and heart failure was significantly higher in deceased patients than in recovered patients. High body mass index, previous history of coronary heart disease, lactic acid accumulation, and a decrease in the partial pressure of oxygen were associated with death. Conclusions All-cause mortality in patients with COVID-19 with CVD in hospitals is high. The high neutrophil/lymphocyte ratio may be a predictor of critical patients. Overweight/obesity combined with coronary heart disease, severe hypoxia, and lactic acid accumulation resulting from respiratory failure are related to poor outcomes. Registration URL: https://www.chictr.org.cn; Unique identifier: ChiCTR2000029865.

Heat Shock Protein 22 Attenuates Doxorubicin-Induced Cardiotoxicity via Regulating Inflammation and Apoptosis.

BACKGROUND: The antitumor effect of doxorubicin (DOX) is limited by its acute and chronic toxicity to the heart, which causes heart injury. Heat shock protein 22 (Hsp22) is a protein proved to exert anti-apoptosis and anti-inflammatory effects in other diseases and physical conditions. In this study, we aim to explore whether Hsp22 could exert a protective role during cardiac injury in response to DOX. METHODS: The overexpression of Hsp22 was mediated via adenovirus vector to clarify the role of Hsp22 in the cardiac injury caused by DOX. DOX-induced acute heart injury mouse model was established by single intraperitoneal injection of DOX (15 mg/kg). Subsequently, cardiac staining and molecular biological analysis were performed to analyze the morphological and biochemical effects of Hsp22 on cardiac injury. H9c2 cells were used for validation in vitro. RESULTS: An increase in the expression level of Hsp22 was observed in DOX-treated heart tissue. Furthermore, cardiac-specific overexpression of Hsp22 showed reduced cardiac dysfunction, decrease in inflammatory response, and reduction in cell apoptosis in injury heart and cardiomyocytes induced by DOX in vivo and in vitro. Moreover, the suppression of Toll-like receptor (TLR)4/NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) was associated with the protective effect of Hsp22. Finally, the protective effect of Hsp22 cardiac function was almost abolished by overexpression of NLRP3 in DOX-treated mice. CONCLUSION: In summary, Hsp22 overexpression in the heart could suppress cardiac injury in response to DOX treatment through blocking TLR4/NLRP3 activation. Hsp22 may become a new therapeutic method for treating cardiac injury induced by DOX in cancer patients.

The Long Noncoding RNA Hotair Regulates Oxidative Stress and Cardiac Myocyte Apoptosis during Ischemia-Reperfusion Injury.

Oxidative stress and subsequent cardiac myocyte apoptosis play central roles in the initiation and progression of myocardial ischemia-reperfusion (I/R) injury. Homeobox transcript antisense intergenic RNA (Hotair) was previously implicated in various heart diseases, yet its role in myocardial I/R injury has not been clearly demonstrated. Mice with cardiac-restricted knockdown or overexpression of Hotair were exposed to I/R surgery. H9c2 cells were cultured and subjected to hypoxia/reoxygenation (H/R) stimulation to further verify the role and underlying mechanisms of Hotair in vitro. Histological examination, molecular detection, and functional parameters were determined in vivo and in vitro. In response to I/R or H/R treatment, Hotair expression was increased in a bromodomain-containing protein 4-dependent manner. Cardiac-restricted knockdown of Hotair exacerbated, whereas Hotair overexpression prevented I/R-induced oxidative stress, cardiac myocyte apoptosis, and cardiac dysfunction. Mechanistically, we observed that Hotair exerted its beneficial effects via activating AMP-activated protein kinase alpha (AMPKα). Further detection revealed that Hotair activated AMPKα through regulating the enhancer of zeste homolog 2/microRNA-451/calcium-binding protein 39 (EZH2/miR-451/Cab39) axis. We provide the evidence that endogenous lncRNA Hotair is an essential negative regulator for oxidative stress and cardiac myocyte apoptosis in myocardial I/R injury, which is dependent on AMPKα activation via the EZH2/miR-451/Cab39 axis.

Interleukin-38 alleviates cardiac remodelling after myocardial infarction.

Excessive immune-mediated inflammatory reaction plays a deleterious role in ventricular remodelling after myocardial infarction (MI). Interleukin (IL)-38 is a newly characterized cytokine of the IL-1 family and has been reported to exert a protective effect in some autoimmune diseases. However, its role in cardiac remodelling post-MI remains unknown. In this study, we found that the expression of IL-38 was increased in infarcted heart after MI induced in C57BL/6 mice by permanent ligation of the left anterior descending artery. In addition, our data showed that ventricular remodelling after MI was significantly ameliorated after recombinant IL-38 injection in mice. This amelioration was demonstrated by better cardiac function, restricted inflammatory response, attenuated myocardial injury and decreased myocardial fibrosis. Our results in vitro revealed that IL-38 affects the phenotype of dendritic cells (DCs) and IL-38 plus troponin I (TNI)-treated tolerogenic DCs dampened adaptive immune response when co-cultured with CD4+ T cells. In conclusion, IL-38 plays a protective effect in ventricular remodelling post-MI, one possibility by influencing DCs to attenuate inflammatory response. Therefore, targeting IL-38 may hold a new therapeutic potential in treating MI.

IL-37 Plays a Beneficial Role in Patients with Acute Coronary Syndrome.

BACKGROUND: Interleukin-37 (IL-37) acts as an inhibitor of innate and adaptive immunity. However, the exact role of IL-37 in the patients with acute coronary syndrome (ACS) remains to be elucidated. METHODS: Patients were classified into 4 groups: normal coronary artery (NCA), stable angina (SA), unstable angina (UA), and acute myocardial infarction (AMI). The circulating Treg, Th1, and Th17 frequencies were measured. The effect of IL-37 on stimulated peripheral blood mononuclear cells (PBMCs) and the influence of IL-37 on DCs were explored. In addition, the role of IL-37-treated tDCs on Treg cell expansion and the stability of these tDCs were also tested. RESULTS: Our results showed that the circulating Treg frequencies were decreased, while Th1 and Th17 frequencies were increased in ACS patients, and that IL-37 expanded Tregs but suppressed Th1 and Th17 cells in activated PBMCs derived from ACS patients. Of note, IL-37-treated human DCs obtained a tolerogenic phenotype, and such tDCs promoted expansion of Tregs and decreased the Th1 and Th17 populations when cocultured with CD4+ T cells. Interestingly, IL-37-treated DCs from patients with ACS are phenotypically and functionally comparable to IL-37-treated DCs from NCA patients, and tolerogenic properties of IL-37-treated DCs were highly stable. CONCLUSION: In conclusion, our results reveal a beneficial role of IL-37 in the patients with ACS and suggest that autologous IL-37-treated tDCs may be a novel therapeutic strategy for the patients with ACS.