姜文阳
中国医学科学院阜外医院 心血管内科
BACKGROUND:Extracellular vesicles (EVs) derived from bone marrow mesenchymal stem cells (MSCs) pretreated with atorvastatin (ATV) (MSCATV-EV) have a superior cardiac repair effect on acute myocardial infarction (AMI). The mechanisms, however, have not been fully elucidated. This study aims to explore whether inflammation alleviation of infarct region via macrophage polarization plays a key role in the efficacy of MSCATV-EV.METHODS:MSCATV-EV or MSC-EV were intramyocardially injected 30 min after coronary ligation in AMI rats. Macrophage infiltration and polarization (day 3), cardiac function (days 0, 3, 7, 28), and infarct size (day 28) were measured. EV small RNA sequencing and bioinformatics analysis were conducted for differentially expressed miRNAs between MSCATV-EV and MSC-EV. Macrophages were isolated from rat bone marrow for molecular mechanism analysis. miRNA mimics or inhibitors were transfected into EVs or macrophages to analyze its effects on macrophage polarization and cardiac repair in vitro and in vivo.RESULTS:MSCATV-EV significantly reduced the amount of CD68+ total macrophages and increased CD206+ M2 macrophages of infarct zone on day 3 after AMI compared with MSC-EV group (P < 0.01-0.0001). On day 28, MSCATV-EV much more significantly improved the cardiac function than MSC-EV with the infarct size markedly reduced (P < 0.05-0.0001). In vitro, MSCATV-EV also significantly reduced the protein and mRNA expressions of M1 markers but increased those of M2 markers in lipopolysaccharide-treated macrophages (P < 0.05-0.0001). EV miR-139-3p was identified as a potential cardiac repair factor mediating macrophage polarization. Knockdown of miR-139-3p in MSCATV-EV significantly attenuated while overexpression of it in MSC-EV enhanced the effect on promoting M2 polarization by suppressing downstream signal transducer and activator of transcription 1 (Stat1). Furthermore, MSCATV-EV loaded with miR-139-3p inhibitors decreased while MSC-EV loaded with miR-139-3p mimics increased the expressions of M2 markers and cardioprotective efficacy.CONCLUSIONS:We uncovered a novel mechanism that MSCATV-EV remarkably facilitate cardiac repair in AMI by promoting macrophage polarization via miR-139-3p/Stat1 pathway, which has the great potential for clinical translation.
BMC medicine 2023
PURPOSE:In recent decades, the occurrence of heart failure with preserved ejection fraction (HFpEF) has outweighed that of heart failure with reduced ejection fraction by degrees, but few drugs have been demonstrated to improve long-term clinical outcomes in patients with HFpEF. Levosimendan, a calcium-sensitizing cardiotonic agent, improves decompensated heart failure clinically. However, the anti-HFpEF activities of levosimendan and underlying molecular mechanisms are unclear.METHODS:In this study, a double-hit HFpEF C57BL/6N mouse model was established, and levosimendan (3 mg/kg/week) was administered to HFpEF mice aged 13 to 17 weeks. Different biological experimental techniques were used to verify the protective effects of levosimendan against HFpEF.RESULTS:After four weeks of drug treatment, left ventricular diastolic dysfunction, cardiac hypertrophy, pulmonary congestion, and exercise exhaustion were significantly alleviated. Junction proteins in the endothelial barrier and between cardiomyocytes were also improved by levosimendan. Among the gap junction channel proteins, connexin 43, which was especially highly expressed in cardiomyocytes, mediated mitochondrial protection. Furthermore, levosimendan reversed mitochondrial malfunction in HFpEF mice, as evidenced by increased mitofilin and decreased ROS, superoxide anion, NOX4, and cytochrome C levels. Interestingly, after levosimendan administration, myocardial tissue from HFpEF mice showed restricted ferroptosis, indicated by an increased GSH/GSSG ratio; upregulated GPX4, xCT, and FSP-1 expression; and reduced intracellular ferrous ion, MDA, and 4-HNE levels.CONCLUSION:Regular long-term levosimendan administration can benefit cardiac function in a mouse model of HFpEF with metabolic syndromes (namely, obesity and hypertension) by activating connexin 43-mediated mitochondrial protection and sequential ferroptosis inhibition in cardiomyocytes.
Cardiovascular drugs and therapy 2023
With the development of stem cell therapy in translational research and regenerative medicine, bone marrow mesenchymal stem cells (BM-MSCs), as a kind of pluripotent stem cells, are favored for their instant availability and proven safety. It has been reported that transplantation of BM-MSCs is of great benefit to repairing injured tissues in various diseases, which might be related to modulating the immune and inflammatory responses via paracrine mechanisms. Extracellular vesicles (EVs), featuring a double-layer lipid membrane structure, are considered to be the main mediators of the paracrine effects of stem cells. Recognized for their crucial roles in cell communication and epigenetic regulation, EVs have already been applied in vivo for immunotherapy. However, similar to its maternal cells, most of the studies on the efficacy of transplantation of EVs still remain at the level of small animals, which is not enough to provide essential evidence for clinical translation. Here, we use density-gradient centrifugation to isolate bone marrow cells (BMC) from porcine bone marrow at first, and get porcine BM-MSCs (pBM-MSCs) by cell culture subsequently, identified by the results of observation under the microscope, induced differentiation assay, and flow cytometry. Furthermore, we isolate EVs derived from pBM-MSCs in cell supernatant by ultracentrifugation, proved by the techniques of transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blotting successfully. Overall, pBM-MSCs and their derived EVs can be isolated and identified effectively by the following protocols, which might be widely used in pre-clinical studies on the transplantation efficacy of BM-MSCs and their derived EVs.
Journal of visualized experiments : JoVE 2022
BACKGROUND:Bone marrow cells (BMCs), especially mesenchymal stem cells (MSCs), have shown attractive application prospects in acute myocardial infarction (AMI). However, the weak efficacy becomes their main limitation in clinical translation. Based on the anti-inflammation and anti-apoptosis effects of a Chinese medicine-Tongxinluo (TXL), we aimed to explore the effects of TXL-pretreated MSCs (MSCsTXL) in enhancing cardiac repair and further investigated the underlying mechanism.METHODS:MSCsTXL or MSCs and the derived exosomes (MSCsTXL-exo or MSCs-exo) were collected and injected into the infarct zone of rat hearts. In vivo, the anti-apoptotic and anti-inflammation effects, and cardiac functional and histological recovery were evaluated. In vitro, the apoptosis was evaluated by western blotting and flow cytometry. miRNA sequencing was utilized to identify the significant differentially expressed miRNAs between MSCsTXL-exo and MSCs-exo, and the miRNA mimics and inhibitors were applied to explore the specific mechanism.RESULTS:Compared to MSCs, MSCsTXL enhanced cardiac repair with reduced cardiomyocytes apoptosis and inflammation at the early stage of AMI and significantly improved left ventricular ejection fraction (LVEF) with reduced infarct size in an exosome-dependent way. Similarly, MSCsTXL-exo exerted superior therapeutic effects in anti-apoptosis and anti-inflammation, as well as improving LVEF and reducing infarct size compared to MSCs-exo. Further exosomal miRNA analysis demonstrated that miR-146a-5p was the candidate effector of the superior effects of MSCsTXL-exo. Besides, miR-146a-5p targeted and decreased IRAK1, which inhibited the nuclear translocation of NF-κB p65 thus protecting H9C2 cells from hypoxia injury.CONCLUSIONS:This study suggested that MSCsTXL markedly facilitated cardiac repair via a new mechanism of the exosomal transfer of miR-146a-5p targeting IRAK1/NF-κB p65 pathway, which has great potential for clinical translation.
Stem cell research & therapy 2022
Lethal intestinal tissue toxicity is a common side effect and a dose-limiting factor in chemoradiotherapy. Chemoradiotherapy can trigger DNA damage and induce P53-dependent apoptosis in LGR5+ intestinal stem cells (ISCs). Gamma-aminobutyric acid (GABA) and its A receptors (GABAAR) are present in the gastrointestinal tract. However, the functioning of the GABAergic system in ISCs is poorly defined. We found that GABAAR α1 (GABRA1) levels increased in the murine intestine after chemoradiotherapy. GABRA1 depletion in LGR5+ ISCs protected the intestine from chemoradiotherapy-induced P53-dependent apoptosis and prolonged animal survival. The administration of bicuculline, a GABAAR antagonist, prevented chemoradiotherapy-induced ISC loss and intestinal damage without reducing the chemoradiosensitivity of tumors. Mechanistically, it was associated with the reduction of reactive oxygen species-induced DNA damage via the L-type voltage-dependent Ca2+ channels. Notably, flumazenil, a GABAAR antagonist approved by the U.S. Food and Drug Administration, rescued human colonic organoids from chemoradiotherapy-induced toxicity. Therefore, flumazenil may be a promising drug for reducing the gastrointestinal side effects of chemoradiotherapy.
The Journal of experimental medicine 2022
Objective:To investigate the optimal percutaneous coronary intervention (PCI) strategy in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel coronary artery disease.Methods:Trials that randomized patients with STEMI and multivessel coronary artery disease to immediate multivessel PCI, staged multivessel PCI, or culprit-only PCI and prospective observational studies that investigated all-cause death were included. Random effect risk ratio (RR) and 95% confidence interval (CI) were calculated.Results:A total of 13 randomized trials with 7627 patients and 21 prospective observational studies with 60311 patients were included. In the pairwise and network meta-analysis based on randomized trials, immediate or staged multivessel PCI was associated with a lower risk of long-term major adverse cardiac events (MACE; RR: 0.58; 95% CI: 0.45 to 0.74) than culprit-only PCI, which was mainly due to lower risks of myocardial infarction (RR: 0.67; 95% CI: 0.51 to 0.88) and revascularization (RR: 0.38; 95% CI: 0.28 to 0.51), without any significant difference in all-cause death (RR: 0.85; 95% CI: 0.69 to 1.04; I 2 = 0.0%). However, short-term outcomes were deficient in randomized trials. The results from real-world prospective observational studies suggested that staged multivessel PCI reduced long-term all-cause death (RR: 0.53; 95% CI: 0.39 to 0.71; I 2 = 15.6%), whereas immediate multivessel PCI increased short-term all-cause death (RR: 1.58; 95% CI: 1.22 to 2.05; I 2 = 43.8%) relative to culprit-only PCI.Conclusion:For patients in randomized trials, multivessel PCI in an immediate or staged procedure was preferred due to improvements in long-term outcomes. As a supplement, the results in real-world patients derived from prospective observational studies suggested that staged multivessel PCI was superior to immediate multivessel PCI. Therefore, staged multivessel PCI may be the optimal PCI strategy for patients with STEMI and multivessel coronary artery disease.
Therapeutic advances in chronic disease 2022
BACKGROUND:Bone marrow-derived mesenchymal stem cells (MSCs), which possess immunomodulatory characteristic, are promising candidates for the treatment of acute myocardial infarction (AMI). However, the low retention and survival rate of MSCs in the ischemic heart limit their therapeutic efficacy. Strategies either modifying MSCs or alleviating the inflammatory environment, which facilitates the recruitment and survival of the engrafted MSCs, may solve the problem. Thus, we aimed to explore the therapeutic efficacy of sequential transplantation of exosomes and combinatorial pretreated MSCs in the treatment of AMI.METHODS:Exosomes derived from MSCs were delivered to infarcted hearts through intramyocardial injection followed by the intravenous infusion of differentially pretreated MSCs on Day 3 post-AMI. Enzyme linked immunosorbent assay (ELISA) was performed to evaluate the inflammation level as well as the SDF-1 levels in the infarcted border zone of the heart. Echocardiography and histological analysis were performed to assess cardiac function, infarct size, collagen area and angiogenesis.RESULTS:Sequential transplantation of exosomes and the combinatorial pretreated MSCs significantly facilitated cardiac repair compared to AMI rats treated with exosomes alone. Notably, compared to the other three methods of cotransplantation, combinatorial pretreatment with hypoxia and Tongxinluo (TXL) markedly enhanced the CXCR4 level of MSCs and promoted recruitment, which resulted in better cardiac function, smaller infarct size and enhanced angiogenesis. We further demonstrated that exosomes effectively reduced apoptosis in MSCs in vitro.CONCLUSION:Sequential delivery of exosomes and pretreated MSCs facilitated cardiac repair post-AMI, and combined pretreatment with hypoxia and TXL better enhanced the cardioprotective effects. This method provides new insight into the clinical translation of stem cell-based therapy for AMI.
Stem cell research & therapy 2022
BACKGROUND:The recent randomized trials demonstrated that culprit-only percutaneous coronary intervention (CO-PCI) was superior to multivessel PCI (MV-PCI) among ST-segment elevation myocardial infarction (STEMI) patients with multivessel disease (MVD) complicated by cardiogenic shock, yet the real-world scenario remains to be determined.METHODS:Studies that compared CO-PCI versus MV-PCI in STEMI patients with MVD complicated by cardiogenic shock were identified by a systematic search of published articles. Pooled odds ratios (OR) and 95% confidence intervals (CI) were calculated by using random-effects models.RESULTS:Eventually, 18 observational studies involving 73,528 patients were included. The results showed that CO-PCI was associated with lower risks of short-term renal failure (OR: 0.75; 95% CI: 0.64 to 0.88; I2=14.7%) and short-term stroke (OR: 0.86; 95% CI: 0.77 to 0.96; I2=0.0%) compared with immediate MV-PCI. But the risk of short-term myocardial infarction (OR: 1.12; 95% CI: 1.03 to 1.22; I2=0.0%) was increased. There was no significant difference during long-term follow-up. The results remained consistent after adding the only randomized trial.DISCUSSION:Based on real-world analyses, our meta-analysis suggested that CO-PCI decreased the risks of renal failure and stroke but increased the risk of myocardial infarction relative to immediate MV-PCI during short-term follow-up in STEMI patients with MVD complicated by cardiogenic shock. If possible in clinical practice, staged MV-PCI can be given a try to decrease the risks of renal failure and stroke associated with immediate MV-PCI and myocardial infarction associated with CO-PCI. However, the conclusions need to be confirmed by further large-scale studies.
Annals of palliative medicine 2021
Cardiac fibrosis, a common pathophysiologic process in most heart diseases, refers to an excess of extracellular matrix (ECM) deposition by cardiac fibroblasts (CFs), which can lead to cardiac dysfunction and heart failure subsequently. Not only CFs but also several other cell types including macrophages and endothelial cells participate in the process of cardiac fibrosis via different molecular pathways. Exosomes, ranging in 30-150 nm of size, have been confirmed to play an essential role in cellular communications by their bioactive contents, which are currently a hot area to explore pathobiology and therapeutic strategy in multiple pathophysiologic processes including cardiac fibrosis. Cardioprotective factors such as RNAs and proteins packaged in exosomes make them an excellent cell-free system to improve cardiac function without significant immune response. Emerging evidence indicates that targeting selective molecules in cell-derived exosomes could be appealing therapeutic treatments in cardiac fibrosis. In this review, we summarize the current understandings of cellular effectors, molecular pathways, and exosomal roles in cardiac fibrosis.
Frontiers in cardiovascular medicine 2021
BACKGROUND:The impact of fibrinolysis-first strategy on outcomes of patients with ST-segment-elevation myocardial infarction (STEMI) during the COVID-19 pandemic was unknown.METHODS:Data from STEMI patients presenting to Fuwai Hospital from January 23 to April 30, 2020 were compared with those during the equivalent period in 2019. The primary end-point was net adverse clinical events (NACE; a composite of death, non-fatal myocardial reinfarction, stroke, emergency revascularization, and bleeding over BARC type 3). The secondary outcome was a composite of recurrent ischaemia, cardiogenic shock, and exacerbated heart failure.RESULTS:The final analysis included 164 acute STEMI patients from 2020 and 240 from 2019. Eighteen patients (20.2% of those with indications) received fibrinolysis therapy in 2020 with a median door-to-needle time of 60.0 (43.5, 92.0) minutes. Patients in 2020 underwent primary PCI less frequently than their counterparts (14 [14.2%] vs. 144 [86.8%] in 2019, P < 0.001), and had a longer median door-to-balloon time (175 [121,213] minutes vs. 115 [83, 160] minutes in 2019, P = 0.009). Patients were more likely to undergo elective PCI (86 [52.4%] vs. 28 [11.6%] in 2019, P < 0.001). The in-hospital NACE was similar between 2020 and 2019 (14 [8.5%] vs. 25 [10.4%], P = 0.530), while more patients developed a secondary outcome in 2020 (20 [12.2%] vs. 12 [5.0%] in 2019, P = 0.009).CONCLUSIONS:The fibrinolysis-first strategy during the COVID-19 pandemic was associated with a lower rate of timely coronary reperfusion and increased rates of recurrent ischaemia, cardiogenic shock, and exacerbated heart failure. However, the in-hospital NACE remained similar to that in 2019.
International journal of cardiology 2021
