Empagliflozin attenuates doxorubicin-induced cardiotoxicity by inhibiting the JNK signaling pathway.

BACKGROUND: Sodium-glucose cotransporter-2 inhibitors, such as empagliflozin, are pivotal therapies for heart failure. However, the effect of empagliflozin on doxorubicin-related cardiac dysfunction remains unclear. METHODS: Human induced pluripotent stem cell- and embryonic stem cell-derived cardiomyocytes were used to investigate the direct effect of empagliflozin on human cardiomyocytes. Then, the c-Jun amino-terminal kinases (JNK) inhibitor SP600125 was administered to the doxorubicin cardiotoxicity model in vitro and in vivo to investigate the role of JNK in empagliflozin. RESULTS: In human stem cell-derived cardiomyocytes, pretreatment with empagliflozin attenuated doxorubicin-induced cleavage of caspase 3 and other apoptosis markers. Empagliflozin significantly attenuated doxorubicin-induced phosphorylation of JNK and p38. Inhibiting the phosphorylation of JNK (SP600125) or STAT3 attenuated doxorubicin-induced apoptosis, but inhibiting the phosphorylation of p38 did not. SP600125 inhibits the phosphorylation of STAT3 (S727), and a STAT3 (Y705) inhibitor also inhibits the phosphorylation of JNK. Empagliflozin and SP600125 attenuated doxorubicin-induced increases in reactive oxygen species (ROS) and decreases in oxidized nicotinamide adenine dinucleotide (NAD+). In animal studies, empagliflozin and SP600125 attenuated doxorubicin-induced cardiac dysfunction and fibrosis. CONCLUSIONS: Empagliflozin attenuated doxorubicin-induced apoptosis by inhibiting the phosphorylation of JNK and its downstream signaling pathways, including ROS and NAD+.

Health Beliefs, Protective Behaviors, and Information-Seeking.

BACKGROUND: The outbreak of COVID-19 caused severe damage to public health globally and served as a stark reminder of the potential for future pandemics. Promoting protective behaviors to prevent the spread of any contagious disease thus remains a priority. Although research has shown that health beliefs can affect protective behaviors, few studies have examined the role of information-seeking in this relationship. OBJECTIVES: On the basis of the health belief model, this research focused on whether health beliefs affect personal protective behaviors through health information-seeking behaviors. METHODS: This cross-sectional study with a causal-comparative design used an online questionnaire to investigate the Taiwanese public's health beliefs, protective behaviors, and information-seeking behaviors during the COVID-19 pandemic. Data were analyzed using descriptive statistics and multiple regression analysis. RESULTS: Between September 2021 and January 2022, 322 valid questionnaires were collected. The results revealed that the effects of two health beliefs-self-efficacy and perceived benefits-on handwashing, social distancing, practicing good cough etiquette, and keeping one's environment clean and well ventilated were partially mediated by the frequency of official information-seeking. DISCUSSION: Results of this study support the regular and timely promotion of pandemic prevention measures through official sites. Promoting official information-seeking can help enhance protective behaviors.

Gut butyrate-producers confer post-infarction cardiac protection.

The gut microbiome and its metabolites are increasingly implicated in several cardiovascular diseases, but their role in human myocardial infarction (MI) injury responses have yet to be established. To address this, we examined stool samples from 77 ST-elevation MI (STEMI) patients using 16 S V3-V4 next-generation sequencing, metagenomics and machine learning. Our analysis identified an enriched population of butyrate-producing bacteria. These findings were then validated using a controlled ischemia/reperfusion model using eight nonhuman primates. To elucidate mechanisms, we inoculated gnotobiotic mice with these bacteria and found that they can produce beta-hydroxybutyrate, supporting cardiac function post-MI. This was further confirmed using HMGCS2-deficient mice which lack endogenous ketogenesis and have poor outcomes after MI. Inoculation increased plasma ketone levels and provided significant improvements in cardiac function post-MI. Together, this demonstrates a previously unknown role of gut butyrate-producers in the post-MI response.

HLA-Ehigh /HLA-Ghigh /HLA-IIlow Human iPSC-Derived Cardiomyocytes Exhibit Low Immunogenicity for Heart Regeneration.

Although human pluripotent stem cells (hPSCs)-derived cardiomyocytes (hPSC-CMs) can remuscularize infarcted hearts and restore post-infarct cardiac function, post-transplant rejection resulting from human leukocyte antigen (HLA) mismatching is an enormous obstacle. It is crucial to identify hypoimmunogenic hPSCs for allogeneic cell therapy. This study is conducted to demonstrate the immune privilege of HLA-Ehigh /HLA-Ghigh /HLA-IIlow human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs). Ischemia-reperfusion surgery is done to create transmural myocardial infarction in rats. At post-infarct 4 days, hPSC-CMs (1.0×107 cells per kg), including human embryonic stem cell-derived cardiomyocytes (hESC-CMs), HLA-Elow/HLA-Glow/HLA-IIhigh hiPSC-CMs, and HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs, are injected into the infarcted myocardium. Under the treatment of very low dose cyclosporine A (CsA), only HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs survive in vivo and improved post-infarct cardiac function with infarct size reduction. HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs activate the SHP-1 signaling pathway of natural killer (NK) cells and cytotoxic T cells to evade attack by NK cells and cytotoxic T cells. Herein, it is demonstrated that using a clinically relevant CsA dose, HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs repair the infarcted myocardium and restore the post-infarct heart function. HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSCs are less immunogenic and may serve as platforms for regeneration medicine.

Combined Treatment of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes and Endothelial Cells Regenerate the Infarcted Heart in Mice and Non-Human Primates.

BACKGROUND: Remuscularization of the mammalian heart can be achieved after cell transplantation of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs). However, several hurdles remain before implementation into clinical practice. Poor survival of the implanted cells is related to insufficient vascularization, and the potential for fatal arrhythmogenesis is associated with the fetal cell-like nature of immature CMs. METHODS: We generated 3 lines of hiPSC-derived endothelial cells (ECs) and hiPSC-CMs from 3 independent donors and tested hiPSC-CM sarcomeric length, gap junction protein, and calcium-handling ability in coculture with ECs. Next, we examined the therapeutic effect of the cotransplantation of hiPSC-ECs and hiPSC-CMs in nonobese diabetic-severe combined immunodeficiency (NOD-SCID) mice undergoing myocardial infarction (n≥4). Cardiac function was assessed by echocardiography, whereas arrhythmic events were recorded using 3-lead ECGs. We further used healthy non-human primates (n=4) with cell injection to study the cell engraftment, maturation, and integration of transplanted hiPSC-CMs, alone or along with hiPSC-ECs, by histological analysis. Last, we tested the cell therapy in ischemic reperfusion injury in non-human primates (n=4, 3, and 4 for EC+CM, CM, and control, respectively). Cardiac function was evaluated by echocardiography and cardiac MRI, whereas arrhythmic events were monitored by telemetric ECG recorders. Cell engraftment, angiogenesis, and host-graft integration of human grafts were also investigated. RESULTS: We demonstrated that human iPSC-ECs promote the maturity and function of hiPSC-CMs in vitro and in vivo. When cocultured with ECs, CMs showed more mature phenotypes in cellular structure and function. In the mouse model, cotransplantation augmented the EC-accompanied vascularization in the grafts, promoted the maturity of CMs at the infarct area, and improved cardiac function after myocardial infarction. Furthermore, in non-human primates, transplantation of ECs and CMs significantly enhanced graft size and vasculature and improved cardiac function after ischemic reperfusion. CONCLUSIONS: These results demonstrate the synergistic effect of combining iPSC-derived ECs and CMs for therapy in the postmyocardial infarction heart, enabling a promising strategy toward clinical translation.

Application of genetic risk score for in-stent restenosis of second- and third-generation drug-eluting stents in geriatric patients.

BACKGROUND: The second-and third-generation drug-eluting stents (DESs) in-stent restenosis (ISR) genetic risk score (GRS) model has been previously validated. However, the model has not been validated in geriatric patients. Therefore, we conducted this study to test the feasibility of the DES-ISR GRS model in geriatric patients with coronary artery disease (CAD) in Taiwan. METHODS: We conducted a retrospective, single-center cohort study and included geriatric patients (age ≥ 65 years) with CAD and second-or third-generation DES(s) deployment. Patients undergoing maintenance dialysis were excluded. ISR was defined as ≥ 50% luminal narrowing on the follow-up coronary arteriography. The DES-ISR GRS model included five selected exonic single-nucleotide polymorphisms (SNPs): CAMLG, GALNT2, C11orf84, THOC5, and SAMD11. The GRS was defined as the sum of the five selected SNPs for the risk allele. RESULTS: We enrolled 298 geriatric patients from January 2010 and December 2019 in this study. After propensity score matching, there were 192 geriatric patients with CAD in the final analysis, of which 32 patients had ISR. Patients were divided into two groups based on their GRS values: low (0-2) and high (≥ 3) GRS. A high GRS was significantly associated with DES-ISR in geriatric patients. CONCLUSION: Those geriatric patients with a high GRS had significantly higher second-or third-generation DES ISR rates. The five SNP-derived DES-ISR GRS model could provide genetic information for interventional cardiologists to treat geriatric patients with CAD. TRIAL REGISTRATION: The primary study protocol was registered with clinicaltrials.org. with registration number: NCT03877614; on March 15, 2019. ( http://clinicaltrials.gov/ct2/show/NCT03877614 ).

Significance of strictly defined idiopathic tricuspid regurgitation.

BACKGROUND: Moderate to severe tricuspid regurgitation (TR) is known to cause right ventricular (RV) failure and death. Although TR is traditionally classified as primary or secondary, recently, a new class of TR called idiopathic TR has been proposed, with varying definitions among different studies. METHODS: The data were retrospectively collected for the period of January to June 2018 for 8711 patients from the patient cohort of the National Cheng Kung University Hospital echocardiography laboratory. A total of 670 patients (7.7%) with moderate-to-severe TR were included. Idiopathic TR was diagnosed strictly using a new systematic approach. RESULTS: The distribution of significant TR included 74 (11.0%) primary TR cases, 48 (7.2%) with pacemaker-related TR, 267 (39.9%) with left heart disease, 24 (3.6%) with congenital heart disease, 6 (0.9%) with RV myopathy, 105 (15.7%) with pulmonary hypertension, and 146 (21.8%) with idiopathic TR. The mean age in primary and idiopathic TR groups was older ( p = 0.004), with lower estimated pulmonary pressure ( p < 0.001), higher RV fraction area change (FAC, p < 0.001), and tricuspid annulus systolic velocity (S', p = 0.004) compared with functional TR group. Multivariate analysis showed that idiopathic TR ( p = 0.002) and primary TR ( p = 0.008) had better RV FAC than functional TR. CONCLUSION: Idiopathic TR was associated with better RV function than the other secondary TRs. Thus, idiopathic TR should be strictly defined and regarded as a distinct type of TR.

Pentraxin 3 regulates tyrosine kinase inhibitor-associated cardiomyocyte contraction and mitochondrial dysfunction via ERK/JNK signalling pathways.

BACKGROUND: Hepatocellular carcinoma (HCC) patients suffer varying degrees of heart dysfunction after tyrosine kinase inhibitor (TKI) treatment. Interestingly, HCC patients often have higher levels of pentraxin 3 (PTX3), and PTX3 inhibition was found to improve left ventricular dysfunction in animal models. OBJECTIVES: We sought to assess the therapeutic potential of PTX3 inhibition on TKI-associated cardiotoxicity. METHODS: We used a human embryonic stem cell line, RUES2, to generate cardiomyocyte cultures (RUES2-CM) for functional testing. We also assessed heart function and PTX3 expression levels in 16 HCC patients who received TKI treatment, 3 HCC patients who did not receive TKIs, and 7 healthy volunteers. RESULTS: Significantly higher PTX3 expression was noted in HCC patients with TKI treatment versus those without, and 38% of male and 33% of female patients had QTc prolongation after TKI treatment. Treatment of cardiomyocyte cultures with sorafenib also increased PTX3 expression and induced cytoskeletal remodelling, contraction reduction, sodium current inhibition, and mitochondrial respiratory dysfunction. PTX3 colocalised with CD44 in cardiomyocytes, and cardiomyocyte contraction, mitochondrial respiratory function, and regular cytoskeletal and apoptotic protein expression were restored with PTX3 inhibition. CD44 knockdown confirmed PTX3/CD44 signalling. These results suggest a possible mechanism in which sorafenib treatment increases PTX3 expression, thereby resulting in reduced extracellular signal-regulated kinase (ERK) 1/2 expression that affects cardiomyocyte contraction, while also activating c-Jun N-terminal kinase (JNK) downstream pathways to disrupt mitochondrial respiration and trigger apoptosis. CONCLUSIONS: TKI-induced cardiotoxicity may be partly mediated by the upregulation of PTX3, and thus PTX3 inhibition has potential as a therapeutic strategy.

Merits of hiPSC-Derived Cardiomyocytes for In Vitro Research and Testing Drug Toxicity.

The progress of medical technology and scientific advances in the field of anticancer treatment have increased the survival probabilities and duration of life of patients. However, cancer-therapy-induced cardiac dysfunction remains a clinically salient problem. Effective anticancer therapies may eventually induce cardiomyopathy. To date, several studies have focused on the mechanisms underlying cancer-treatment-related cardiotoxicity. Cardiomyocyte cell lines with no contractile physiological characteristics cannot adequately model "true" human cardiomyocytes. However, applying "true" human cardiomyocytes for research is fraught with many obstacles (e.g., invasiveness of the procedure), and there is a proliferative limitation for rodent primary cultures. Human-induced pluripotent stem-cell-differentiated cardiomyocytes (hiPSC-CMs), which can be produced efficiently, are viable candidates for mimicking human cardiomyocytes in vitro. We successfully performed cardiac differentiation of human iPSCs to obtain hiPSC-CMs. These hiPSC-CMs can be used to investigate the pathophysiological basis and molecular mechanism of cancer-treatment-related cardiotoxicity and to develop novel strategies to prevent and rescue such cardiotoxicity. We propose that hiPSC-CMs can be used as an in vitro drug screening platform to study targeted cancer-therapy-related cardiotoxicity.

Tumor endothelial marker 1 is upregulated in heart after cardiac injury and participates in cardiac remodeling.

Tumor endothelial marker 1 (TEM1) is a transmembrane glycoprotein that appears on mesenchymal lineage-derived cells during embryogenesis, but its expression greatly reduces after birth. Re-upregulation of TEM1 is found in tumor angiogenesis, organ fibrosis and wound healing indicating its potential role in tissue remodeling and repair. The expression level and function of TEM1 in adult heart are unknown. In explanted hearts from heart failure (HF) patients received cardiac transplantation, immunofluorescence staining showed TEM1 was expressed in cardiomyocytes (CMs) and cardiac fibroblasts. Bioinformatics analysis showed TEM1 upregulation in mouse heart after coronary ligation. Cardiac TEM1 expression was reconfirmed in mouse HF induced by coronary ligation or doxorubicin injection. TEM1 expression increased in cultured CMs stimulated with mechanical stretch, doxorubicin and hypoxia. Further studies showed recombinant TEM1 (rTEM1) was a functional protein that influenced cell behaviors of CMs. It directly activated Erk and Akt through interaction with PDGF receptor. TEM1lacZ/lacZ mice had less collagen deposition and worse cardiac function than wild type mice. These results indicate that TEM1 expression increases in the heart after cardiac injury and works as a functional protein that participates in cardiac remodeling.

Risk Management for Radiation-Induced Cardiovascular Disease (RICVD): The 2022 Consensus Statement of the Taiwan Society for Therapeutic Radiology and Oncology (TASTRO) and Taiwan Society of Cardiology (TSOC).

Advances in cancer management have significantly improved survival in patients with cancers. Cardiovascular complications of cancer treatment are becoming significant competing causes of death in these patients. Radiotherapy is an indispensable component of cancer treatment, and irradiation of the heart and vasculature during cancer radiotherapy is now recognized as a new risk factor for cardiovascular diseases. It is important to involve multidisciplinary expertise and provide practical recommendations to promote awareness, recognize risks, and provide adequate interventions without jeopardizing cancer control. In this consensus paper, experts from the Taiwan Society for Therapeutic Radiology and Oncology and Taiwan Society of Cardiology provide a focused update on the clinical practice for risk stratification and management of radiation-induced cardiovascular disease (RICVD). We believe that implementing RICVD care under a collaborative cardio-oncology program will significantly improve cancer treatment outcomes and will facilitate high quality clinical investigations.

Real-time exercise reduces impaired cardiac function in breast cancer patients undergoing chemotherapy: A randomized controlled trial.

BACKGROUND: Previous studies have reported that chemotherapy results in substantial long-term risk of heart failure. Exercise ameliorates exercise responses and exercise tolerance in patients receiving chemotherapy. The cardioprotective effect of real-time exercise in breast cancer is still unclear. OBJECTIVES: The aim of the present study was to determine the effect of real-time moderate-to-high-intensity exercise training in women with breast cancer undergoing chemotherapy and to follow up on parameters of cardiac function and exercise capacity at different times. We hypothesized that early moderate-to-high-intensity exercise training has beneficial effects on cardiac function in women with breast cancer undergoing chemotherapy. METHODS: This was a randomized controlled study that included 32 women randomly allocated into the control or exercise group. Exercise began with the first cycle of chemotherapy, and the training program was maintained during chemotherapy with 2 to 3 sessions per week for 3 months. Patients were instructed to perform moderate-to-high-intensity training with aerobic and resistance training. Outcome measurements were echocardiography and cardiopulmonary exercise test. The primary outcome was the change in left ventricle ejection fraction (LVEF). The secondary outcome was peak oxygen consumption (peak VO2). RESULTS: The control group showed lower cardiac systolic function than the exercise group [mean (SD) LVEF 62% (2) and 70% (5), P<0.05], reduced cardiac diastolic function, and cardiac hypertrophy at 3, 6 and 12 months after chemotherapy. At 6 months after chemotherapy, the exercise group exhibited relatively higher exercise capacity than controls [mean (SD) VO2 12.1 (2.2) and 13.6 (2.2) mL/kg/min, P<0.05]. The main effect size of the study based on echocardiography outcomes was 0.25 (95% confidence interval 0.23 to 0.27), a medium effect size. CONCLUSIONS: Moderate-to-high-intensity exercise training in breast cancer patients undergoing chemotherapy may prevent impaired cardiac function. CLINICAL TRIAL REGISTRATION: https://www. CLINICALTRIALS: in.th (Identifier TCTR20190330002).

Genetic risk model for in-stent restenosis of second-and third-generation drug-eluting stents.

The new generation, i.e., second- and third-generation, drug-eluting stents (DESs) remain a risk of in-stent restenosis (ISR). We evaluated the power of a genetic risk score (GRS) model to identify high-risk populations for new generation DES ISR. We enrolled patients with coronary artery disease (CAD) treated with new generations DESs by a single-center cohort study in Taiwan and evaluated their genetic profile. After propensity score matching, there were 343 patients and 153 patients in the derivation and validation cohorts, respectively. Five selected single-nucleotide polymorphisms (SNPs), i.e., SNPs in CAMLG, GALNT2, C11orf84, THOC5, and SAMD11, were included to calculate the GRS for new generation DES ISR. In the derivation and the validation cohorts, patients with a GRS greater than or equal to 3 had significantly higher new generation DES ISR rates. We provide biological information for interventional cardiologists prior to percutaneous coronary intervention by specific five SNP-derived GRS.

Off-label reduced-dose apixaban does not reduce hemorrhagic risk in Taiwanese patients with nonvalvular atrial fibrillation: A retrospective, observational study.

ABSTRACT: East Asians are reportedly at high risk of anticoagulant-related bleeding; therefore, some physicians prefer to prescribe low-dose direct oral anticoagulants (DOACs). Little is known about the therapeutic effectiveness and safety of off-label reduced-dose apixaban in East Asians with nonvalvular atrial fibrillation (AF). We aimed to investigate the effectiveness and safety of off-label reduced-dose apixaban in Taiwanese patients with nonvalvular AF.This retrospective cohort study enrolled 1073 patients with nonvalvular AF who took apixaban between July 2014 and October 2018 from 4 medical centers in southern Taiwan. The primary outcomes included thromboembolic events (stroke/transient ischemic attack or systemic embolism), major bleeding, and all-cause mortality.Among all patients, 826 (77%) patients were classified as the "per-label adequate-dose" treatment group (i.e., consistent with the Food and Drug Administration label recommendations) while 247 (23%) patients were the "off-label reduced-dose" treatment group. The mean follow-up period was 17.5 ±â€Š13 months. The "off-label reduced-dose" group did not have a lower major bleeding rate than the "per-label adequate-dose" group (4.8% vs 3.8%, adjusted hazard ratio [HR] 1.20, 95% confidence interval [CI] 0.69-2.09), but had a nonsignificantly higher incidence of thromboembolic events (4.23% vs 3.05%, adjusted HR: 1.29, 95% CI: 0.71-2.34).An off-label reduced-dose apixaban treatment strategy may not provide incremental benefits or safety for Taiwanese patients with nonvalvular AF.

Subtle cardiac dysfunction in lymphoma patients receiving low to moderate dose chemotherapy.

Left ventricular (LV) global peak systolic longitudinal strain (GLS) is a sensitive measurement for detecting subtle LV systolic dysfunction and a powerful prognostic predictor. However, the clinical implication of LV GLS in lymphoma patients receiving cancer therapy remains unknown. We prospectively enrolled 74 lymphoma patients (57.9 ± 17.0 years old, 57% male). We performed echocardiographic studies after the 3rd and 6th cycles and 1 year after chemotherapy and a cardiopulmonary exercise test upon completion of 3 cycles of anticancer therapy. Cancer therapy-related cardiac dysfunction (CTRCD) was defined as a ≥ 15% relative reduction in GLS value from baseline. The primary outcome was a composite of all-cause mortality and heart failure events. Thirty-six patients (49%) had CTRCD (LV GLS: baseline vs. after 3rd cycle of therapy: 20.1 ± 2.6 vs. 17.5 ± 2.3%, p < 0.001). CTRCD was detected after the 3rd cycle of anticancer therapy. CTRCD patients had impaired exercise capacity (minute oxygen consumption/kg, CTRCD vs. CTRCD (-): 13.9 ± 3.1 vs. 17.0 ± 3.9 ml/kg/min, p = 0.02). More primary outcome events occurred in the CTRCD group (hazard ratio 3.21; 95% confidence interval 1.04-9.97; p = 0.03). LV GLS could detect subtle but clinically significant cardiac dysfunction in lymphoma patients in the early stage of anticancer therapy. CTRCD may be associated with not only a reduced exercise capacity but also a worse prognosis.

The predictive value of global longitudinal strain in patients with heart failure mid-range ejection fraction.

BACKGROUND: Heart failure (HF) with mid-range ejection fraction (HFmrEF) is defined as HF with a left ventricular (LV) ejection fraction (LVEF) of 41-49%. However, the change in LV function and the subsequent prognosis in these patients remain unclear. We aimed to investigate whether LV global longitudinal strain (LV GLS) could differentiate the changes in LVEF and predict the clinical outcomes in patients with HFmrEF. METHODS: According to the changes in LVEF on follow-up echocardiography, 273 outpatients with HFmrEF were divided into 3 groups: HFwEF (HF with worse EF: <40%), HFsEF (HF with similar EF: 40-49%), and HFrecEF (HF with recovered EF: >50%). Further, the LV GLS at diagnosis was evaluated. RESULTS: The average follow-up duration was 31 months. Among patients with HFmrEF, the more impaired the LV GLS at baseline, the higher probability of HFwEF development. In comparison with patients with HFwEF and HFsEF, those with HFrecEF had a lower risk of hospitalization for HF. At a cut-off value of -11%, LV GLS differentiated the subsequent risk of cardiovascular death in patients with HFmrEF. In Cox regression, patients with LV GLS >-11% had a high risk of cardiovascular death. CONCLUSION: In patients with HFmrEF, LV GLS is associated with LVEF changes and subsequent cardiovascular death. Patients with HFrecEF had a lower risk of hospitalization for HF.

The Burden of Ventricular Premature Complex Is Associated With Cardiovascular Mortality.

BACKGROUND: Ventricular premature complex (VPC) is one of the most common ventricular arrhythmias. The presence of VPC is associated with an increased risk of heart failure (HF). METHOD: We designed a single-center, retrospective, and large population-based cohort to clarify the role of VPC burden in long-term prognosis in Taiwan. We analyzed the database from the National Cheng Kung University Hospital-Electronic Medical Record (NCKUH-EMR) and NCKUH-Holter (NCKUH-Holter). A total of 19,527 patients who underwent 24-h Holter ECG monitoring due to palpitation, syncope, and clinical suspicion of arrhythmias were enrolled in this study. RESULTS: The clinical outcome of interests involved 5.65% noncardiovascular death and 1.53% cardiovascular-specific deaths between 2011 and 2018. Multivariate Cox regression analysis, Fine and Gray's competing risk model, and propensity score matching demonstrated that both moderate (1,000-10,000/day) and high (>10,000/day) VPC burdens contributed to cardiovascular death in comparison with a low VPC burden (<1,000/day). CONCLUSION: A higher VPC burden via Holter ECG is an independent risk factor of cardiovascular mortality.

Progress and Challenges of Amniotic Fluid Derived Stem Cells in Therapy of Ischemic Heart Disease.

Cardiovascular disease is the leading cause of deaths worldwide, claiming an estimated total of 17.9 million lives each year, of which one-third of the people are under the age of 70 years. Since adult cardiomyocytes fail to regenerate, the heart loses the ability to repair itself after an injury, making patients with heart disease suffer from poor prognosis. Pluripotent stem cells have the ability to differentiate into cardiomyocytes in vitro through a well-established process, which is a new advancement in cardiac regeneration therapy. However, pluripotent stem cell-derived cardiomyocytes have certain drawbacks, such as the risk of arrhythmia and immune incompatibility. Thus, amniotic fluid stem cells (AFSCs), a relatively novel source of stem cells, have been exploited for their ability of pluripotent differentiation. In addition, since AFSCs are weakly positive for the major histocompatibility class II molecules, they may have high immune tolerance. In summary, the possibility of development of cardiomyocytes from AFSCs, as well as their transplantation in host cells to produce mechanical contraction, has been discussed. Thus, this review article highlights the progress of AFSC therapy and its application in the treatment of heart diseases in recent years.

Immunogenicity in Stem Cell Therapy for Cardiac Regeneration.

Despite enormous advances in the treatment of cardiovascular disease (CVD), heart disease remains the leading cause of mortality and morbidity worldwide. Thus, there is a need for novel CVD therapeutics. CVD appears to be a custom-made scenario for applying stem cell therapy. Although human pluripotent stem cells can differentiate into cardiomyocytes to regenerate injured heart tissue and restore post-myocardial infarction cardiac function, several obstacles need to be overcome before cell therapy can be applied in CVD patients. One of these major hurdles is the immunological barrier. Currently, long-term immunosuppressant treatment is necessary for allogenic stem cell or organ transplantation to prevent rejection. However, the long-term use of immunosuppressants may cause serious adverse events such as nephrotoxicity, severe infections and malignancy. Thus, overcoming this immunological hurdle is crucial for the clinical application of stem cell therapy in cardiac regeneration. This review summarizes the recent advances and challenges of immunogenicity in relation to stem cell therapy.

Programmed Cell Death-1: Programmed Cell Death-Ligand 1 Interaction Protects Human Cardiomyocytes Against T-Cell Mediated Inflammation and Apoptosis Response In Vitro.

AIM: Immunological checkpoint therapy is considered a powerful method for cancer therapy and acts by re-activating autologous T cells to kill the cancer cell. Myocarditis cases have been reported in cancer patients after immunological therapy; for example, nivolumab treatment is a monoclonal antibody that blocks programmed cell death-1/programmed cell death ligand-1 ligand interaction. This project provided insight into the inflammatory response as a benchmark to investigate the potential cardiotoxic effect of T cell response to the programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) axis in regulating cardiomyocyte injury in vitro. METHODS AND RESULTS: We investigated cardiomyopathy resulted from the PD-1/PD-L1 axis blockade using the anti-PD-1 antibody in Rockefeller University embryonic stem cells-derived cardiomyocytes (RUES2-CMs) and a melanoma tumor-bearing murine model. We found that nivolumab alone did not induce inflammatory-related proteins, including PD-L1 expression, and did not induce apoptosis, which was contrary to doxorubicin, a cardiotoxic chemotherapy drug. However, nivolumab was able to exacerbate the immune response by increasing cytokine and inflammatory gene expression in RUES2-CMs when co-cultured with CD4+ T lymphocytes and induced apoptosis. This effect was not observed when RUES2-CMs were co-cultured with CD8+ T lymphocytes. The in vivo model showed that the heart function of tumor-bearing mice was decreased after treatment with anti-PD-1 antibody and demonstrated a dilated left ventricle histological examination. The dilated left ventricle was associated with an infiltration of CD4+ and CD8+ T lymphocytes into the myocardium. PD-L1 and inflammatory-associated gene expression were significantly increased in anti-PD-1-treated tumor-bearing mice. Cleaved caspase-3 and mouse plasma cardiac troponin I expressions were increased significantly. CONCLUSION: PD-L1 expression on cardiomyocytes suppressed T-cell function. Blockade of PD-1 by nivolumab enhanced cardiomyocyte inflammation and apoptosis through the enhancement of T-cell response towards cardiomyocytes.