AMP-activated protein kinase sparks the fire of cardioprotection against myocardial ischemia and cardiac ageing

Prognostic value of the modified Model for End-Stage Liver Disease score in patients treated with cardiac resynchronization therapy

Background

Hepatorenal dysfunction is prevalent among individuals with heart failure (HF).

OBJECTIVE

This study investigated prognostic value of the modified Model for End-Stage Liver Disease (Model for End-Stage Liver Disease excluding international normalized ratio [MELD-XI] scores and Model for End-Stage Liver Disease with albumin replacing international normalized ratio [MELD-Albumin]) score in patients undergoing cardiac resynchronization therapy (CRT).

Methods

We retrospectively evaluated 365 patients (mean age 58.7 ± 11.1 years; 64.9% men) undergoing CRT implantation between 2007 and 2019. Patients were divided into 4 groups based on the modified MELD score quartiles before CRT. The primary endpoint was the combination of all-cause mortality and HF hospitalization, whereas the secondary endpoint was CRT response at 6 months.

Results

During mean follow-up of 3.3 years (interquartile range 1.9-5.2 years), 168 patients reached the primary endpoint. Logistic regression revealed the MELD-Albumin score was independently associated with CRT response, even after adjusting for covariates (odds ratio 1.10; 95% confidence interval [CI] 1.02-1.19; P = .013). Kaplan-Meier analysis revealed that patients with a higher MELD-XI and MELD-Albumin score had a greater risk of adverse outcomes (log-rank test: P < .001). A Cox proportional hazards analysis showed that the modified MELD score remained significantly associated with adverse outcomes after adjusting for clinical and echocardiographic factors (MELD-XI: hazard ratio 1.06, 95% CI 1.02-1.11, P = .006; MELD-Albumin: hazard ratio 1.10, 95% CI 1.05-1.16, P < .001). Furthermore, receiver-operating characteristic analysis indicated that the MELD-Albumin score provided a stronger prognostic value for long-term adverse outcomes in patients undergoing CRT than the MELD-XI score (MELD-Albumin: area under the curve 0.692, 95% CI 0.644-0.742; MELD-XI: area under the curve 0.659, 95% CI 0.608-0.715; P = .008).

Conclusion

The MELD-Albumin score may be useful for stratifying patients at risk for CRT response and adverse outcomes in those undergoing CRT for HF.

Apelin13 Loaded Nano-Niosomes Confer Cardioprotection in a Rat Model of Myocardial Ischemia Reperfusion by Targeting the Nrf2/HO-1 Pathway

Although apelin-13 has cardioprotective impact, its short half-life in the bloodstream has challenged its clinical application. Using nanocarriers can increase the bioavailability, functionality, and stability of drugs. Current investigation aims to find whether apelin13-loaded nano-niosomes confer cardioprotection in an animal model of myocardial ischemia/reperfusion injury (MI/R) via suppressing ferroptosis, targeting Nrf2 pathway, and AMPK/GSK-3β axis. Ligation of the left anterior coronary artery descending was done to establish the MI/R model and 15 μg/kg of apelin13-loaded nano-niosomes were intramyocardially administrated. Echocardiography, RT-PCR, immunohistochemistry, western blot, ELISA kits, and H&E staining were applied to measure the related indicators. Treatment with both apelin13 and apelin13 loaded nano-niosomes could improve cardiac function and attenuate oxidative stress, myocardial inflammatory factors, and hence ferroptosis by activating the Nrf2 and its downstream proteins HO1, NQO1, AMPK/GSK-3β signaling pathway. In conclusion, apelin13-loaded nano-niosomes are effective MI therapeutic agents against MI/R-induced ferroptosis by activation of Nrf2 via AMPK/GSK-3β axis.

Protective effects and bioinformatic analysis of narciclasine on vascular aging via cross-talk between inflammation and metabolism through inhibiting skeletal muscle-specific ceramide synthase 1

OBJECTIVE

The senescence of smooth muscle is one of the independent risk factors in atherosclerosis progression in which the vascular inflammation plays an important role on vascular dysfunction. This study is designed to explore the novel vascular aging biomarkers and screen the potential molecular interventional targets through bioinformatic analysis.

RESULTS

Transcriptional analysis was conducted based on the GSE16487 open access database, which included 15 human vascular tissue samples from two groups: young group (≤ 60 years old, n = 8) and aged group (≥ 75 years old, n = 7). There were 275 differential expression genes (119 upregulated and 156 downregulated genes) with minimum 1.5-fold change between two groups. 9 genes were mainly participated in inflammation-related signaling pathways, in which narciclasine was validated as the most effective candidate for modulation the ceramide synthesis. In vitro and animal study demonstrated that narciclasine reversed vascular aging by inhibiting skeletal muscle-specific ceramide synthase 1 (CerS1), reducing the ceramide level derived from CerS1, and improving fat deposition and circulating glycolipid metabolism.

CONCLUSION

Narciclasine attenuates vascular aging and modulates the cross-talk between inflammation and metabolism via inhibiting skeletal muscle-specific ceramide synthase 1.

The effect of eight weeks of endurance training and MitoQ supplementation on antioxidant capacity and the expression of sestrin-2 and AMPK in cardiac tissue of aged rats

PURPOSE

The present study aimed to investigate the effects of endurance training (ET) in combination with MitoQ supplementation on antioxidant indices and the expression of sesterin-2 (SESN2) as an anti-aging factor and AMPK as an energy sensor in aged male Wistar rats.

METHODS

Twenty-eight aged Wistar rats (410 ± 15 g, 22 ± 1.5 months old) were randomly divided into four groups (n = 7): Control, ET (eight weeks endurance training on the treadmill), MitoQ (250 μ/L in drinking water), and ET + MitoQ. We measured the protein and gene expression of SESN2 and AMPK in the heart tissue by western blotting and real-time PCR, respectively. In addition, antioxidant indices, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activity, and oxidant malondialdehyde (MDA) concentration in the cardiac tissue and serum were measured.

RESULTS

SESN2 and AMPK protein expression significantly increased in the MitoQ group compared to the control group (P = 0.002, P = 0.0003). MDA content in tissue and serum remained unchanged in all groups (P > 0.05). MitoQ supplementation significantly increased SOD and GPx enzyme activity in serum and cardiac tissue (P = 0.001).

CONCLUSION

Overall, ET and MitoQ alone and in combination have anti-aging effects and improve the expression of AMPK and SESN2. Additionally, ET and MitoQ lead to improved antioxidant capacity in aged rats by ameliorating the activity of antioxidant enzymes.

Wulingsan Alleviates MAFLD by Activating Autophagy via Regulating the AMPK/mTOR/ULK1 Signaling Pathway

Here, we presented the study of the molecular mechanisms underlying the action of Wulingsan (WLS) in rats with metabolic-associated fatty liver disease (MAFLD) induced by a high-fat diet (HFD). High-performance liquid chromatography was employed to identify the chemical components of WLS. After 2 weeks of HFD induction, MAFLD rats were treated with WLS in three different doses for 6 weeks, a positive control treatment or with a vehicle. Lipid metabolism, liver function, oxidative stress, and inflammatory factors as well as pathomorphological changes in liver parenchyma were assessed in all groups. Finally, the expressions of autophagy-related markers, adenosine monophosphate-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR)/unc-51-like kinase-1 (ULK1) signaling pathway-related genes, and proteins in liver were detected. The results revealed that WLS significantly ameliorated liver injury, the dysfunction of the lipid metabolism, the oxidative stress, and overall inflammatory status. Furthermore, WLS increased the expressions of LC3B-II, Beclin1, p-AMPK, and ULK1, along with decreased p62, p-mTOR, and sterol regulatory element-binding protein-1c levels. In conclusion, we showed that WLS is capable of alleviating HFD-induced MAFLD by improving lipid accumulation, suppressing oxidative stress and inflammation, and promoting autophagy.

AMPK pathway: an emerging target to control diabetes mellitus and its related complications

Purpose

In this extensive review work, the important role of AMP-activated protein kinase (AMPK) in causing of diabetes mellitus has been highlighted. Structural feature of AMPK as well its regulations and roles are described nicely, and the association of AMPK with the diabetic complications like nephropathy, neuropathy and retinopathy are also explained along with the connection between AMPK and β-cell function, insulin resistivity, mTOR, protein metabolism, autophagy and mitophagy and effect on protein and lipid metabolism.

Methods

Published journals were searched on the database like PubMed, Medline, Scopus and Web of Science by using keywords such as AMPK, diabetes mellitus, regulation of AMPK, complications of diabetes mellitus, autophagy, apoptosis etc.

Result

After extensive review, it has been found that, kinase enzyme like AMPK is having vital role in management of type II diabetes mellitus. AMPK involve in enhance the concentration of glucose transporter like GLUT 1 and GLUT 4 which result in lowering of blood glucose level in influx of blood glucose into the cells; AMPK increases the insulin sensitivity and decreases the insulin resistance and further AMPK decreases the apoptosis of β-cells which result into secretion of insulin and AMPK is also involve in declining of oxidative stress, lipotoxicity and inflammation, owing to which organ damage due to diabetes mellitus can be lowered by activation of AMPK.

Conclusion

As AMPK activation leads to overall control of diabetes mellitus, designing and developing of small molecules or peptide that can act as AMPK agonist will be highly beneficial for control or manage diabetes mellitus.

SIRT3/6: an amazing challenge and opportunity in the fight against fibrosis and aging

Fibrosis is a typical aging-related pathological process involving almost all organs, including the heart, kidney, liver, lung, and skin. Fibrogenesis is a highly orchestrated process defined by sequences of cellular response and molecular signals mechanisms underlying the disease. In pathophysiologic conditions associated with organ fibrosis, a variety of injurious stimuli such as metabolic disorders, epigenetic changes, and aging may induce the progression of fibrosis. Sirtuins protein is a kind of deacetylase which can regulate cell metabolism and participate in a variety of cell physiological functions. In this review, we outline our current understanding of common principles of fibrogenic mechanisms and the functional role of SIRT3/6 in aging-related fibrosis. In addition, sequences of novel protective strategies have been identified directly or indirectly according to these mechanisms. Here, we highlight the role and biological function of SIRT3/6 focus on aging fibrosis, as well as their inhibitors and activators as novel preventative or therapeutic interventions for aging-related tissue fibrosis.

Abnormal expression of PRKAG2-AS results in dysfunction of cardiomyocytes through regulating PRKAG2 transcription by interacting with PPARG

The role of PRKAG2 in the maintenance of heart function is well established, but little is known about how PRKAG2 is regulated in cardiomyocytes. In this study, we investigated the role of the lncRNA PRKAG2-AS, which is present at the PRKAG2 promoter, in the regulation of PRKAG2 expression. PRKAG2-AS expression was predominantly nuclear, as determined by RNA nucleoplasmic separation and fluorescence in situ hybridization. Knockdown of PRKAG2-AS in the nucleus, but not the cytoplasm, significantly decreased the expression of PRKAG2b and PRKAG2d. Interestingly, we found that PRKAG2-AS and its target genes, PRKAG2b and PRKAG2d, were reduced in the hearts of patients with ischemic cardiomyopathy, suggesting a potential role for PRKAG2-AS in myocardial ischemia. Indeed, knockdown of PRKAG2-AS in the nucleus resulted in apoptosis of cardiomyocytes. We further elucidated the mechanism by which PRKAG2-AS regulates PRKAG2 transcription by identifying 58 PRKAG2-AS interacting proteins. Among them, PPARG was selected for further investigation based on its correlation and potential interaction with PRKAG2-AS in regulating transcription. Overexpression of PPARG, or its activation with rosiglitazone, led to a significant increase in the expression of PRKAG2b and PRKAG2d in cardiomyocytes, which could be attenuated by PRKAG2-AS knockdown. This finding suggests that PRKAG2-AS mediates, at least partially, the protective effects of rosiglitazone on hypoxia-induced apoptosis. However, given the risk of rosiglitazone in heart failure, we also examined the involvement of PRKAG2-AS in this condition and found that PRKAG2-AS, as well as PRKAG2b and PRKAG2d, was elevated in hearts with dilated cardiomyopathy (DCM) and that overexpression of PRKAG2-AS led to a significant increase in PRKAG2b and PRKAG2d expression, indicating that up-regulation of PRKAG2-AS may contribute to the mechanism of heart failure by promoting transcription of PRKAG2. Consequently, proper expression of PRKAG2-AS is essential for maintaining cardiomyocyte function, and aberrant PRKAG2-AS expression induced by hypoxia or other stimuli may cause cardiac dysfunction.

Acupuncture improves immunity and fatigue after chemotherapy in breast cancer patients by inhibiting the Leptin/AMPK signaling pathway

OBJECTIVE

Acupuncture has become a popular complementary treatment in oncology. This study is based on RNA-Seq transcriptome sequencing technology to investigate the molecular mechanisms underlying the effect of acupuncture-mediated regulation of the Leptin/AMPK signaling pathway on mitochondrial dysfunction-induced fatigue in breast cancer patients after chemotherapy.

METHODS

Peripheral blood samples from 10 patients with post-operative chemotherapy for breast cancer were selected for transcriptome sequencing to screen the key molecular pathways involved in fatigue after chemotherapy in breast cancer patients. Besides, peripheral blood samples were collected from 138 post-operative chemotherapy patients with breast cancer to study the composite fatigue and quality of life scores. Flow cytometry was used to detect T lymphocyte subsets in peripheral blood-specific immune cells. In addition, a blood cell analyzer was used to measure peripheral blood leukocyte counts, and MSP-PCR was used to detect mitochondrial DNA mutations in peripheral blood leukocytes.

RESULTS

Transcriptome bioinformatics analysis screened 147 up-regulated mRNAs and 160 down-regulated mRNAs. Leptin protein was confirmed as the key factor. Leptin was significantly higher in the peripheral blood of breast cancer patients who developed fatigue after chemotherapy. Acupuncture treatment effectively improved post-chemotherapy fatigue and immune status in breast cancer patients, suppressed the expression of Leptin/AMPK signaling pathway-related factor and leukocyte counts, and significantly reduced the rate of mitochondrial DNA mutations in peripheral blood leukocytes.

CONCLUSION

The Leptin/AMPK signaling pathway may be the key molecular pathway affecting the occurrence of fatigue after chemotherapy in breast cancer patients. Leptin may improve post-chemotherapy fatigue in breast cancer patients by activating AMPK phosphorylation and alleviating mitochondrial functional impairment.

Shengxian decoction protects against chronic heart failure in a rat model via energy regulation mechanisms

BACKGROUND

Chronic heart failure (CHF) is actually a disease caused by an imbalanced energy metabolism between myocardial energy demand and supply, ultimately resulting in abnormal myocardial cell structure and function. Energy metabolism imbalance plays an important role in the pathological process of chronic heart failure (CHF). Improving myocardial energy metabolism is a new strategy for the treatment of CHF. Shengxian decoction (SXT), a well-known traditional Chinese medicine (TCM) formula, has good therapeutic effects on the cardiovascular system. However, the effects of SXT on the energy metabolism of CHF is unclear. In this study, we probed the regulating effects of SXT on energy metabolism in CHF rats using various research methods.

METHODS

High-performance liquid chromatography (HPLC) analysis was used to perform quality control of SXT preparations. Then, SD rats were randomly assigned into 6 groups: sham, model, positive control (trimetazidine) and high-, middle-, and low-dose SXT groups. Specific reagent kits were used to detect the expression levels of ALT and AST in rats' serum. Echocardiography was used to evaluate cardiac function. H&E, Masson and TUNEL staining were performed to examine myocardial structure and myocardial apoptosis. Colorimetry was used to determine myocardial ATP levels in experimental rats. Transmission electron microscopy was used to observe the ultrastructure of myocardial mitochondria. ELISA was used to estimate CK, cTnI, and NT-proBNP levels, and LA、FFA、MDA、SOD levels. Finally, Western blotting was used to examine the protein expression of CPT-1, GLUT4, AMPK, p-AMPK, PGC-1α, NRF1, mtTFA and ATP5D in the myocardium.

RESULTS

HPLC showed that our SXT preparation method was feasible. The results of ALT and AST tests indicate that SXT has no side effect on the liver function of rats. Treatment with SXT improved cardiac function and ventricular remodelling and inhibited cardiomyocyte apoptosis and oxidative stress levels induced by CHF. Moreover, CHF caused decrease ATP synthesis, which was accompanied by a reduction in ATP 5D protein levels, damage to mitochondrial structure, abnormal glucose and lipid metabolism, and changes in the expression of PGC-1α related signal pathway proteins, all of which were significantly alleviated by treatment with SXT.

CONCLUSION

SXT reverses CHF-induced cardiac dysfunction and maintains the integrity of myocardial structure by regulating energy metabolism. The beneficial effect of SXT on energy metabolism may be related to regulating the expression of the PGC-1α signalling pathway.

The role of NLRP3 inflammasome-mediated pyroptosis in ischemic stroke and the intervention of traditional Chinese medicine

Ischemic stroke (IS) is the second leading cause of death and disability in the world. Pyroptosis, a form of programmed cell death initiated by caspases, participates in the occurrence and development of IS. Because it can increase cell membrane permeability, mediate the release of inflammatory factors, and aggravate inflammation, inhibiting this process can significantly reduce the pathological injury of IS. The nucleotide binding oligomerization domain-like receptor family pyrin domain protein 3 (NLRP3) is a multiprotein complex whose activation is the core link of pyroptosis. In recent years, studies have reported that traditional Chinese medicine (TCM) could regulate pyroptosis mediated by NLRP3 inflammasome through multi-channel and multi-target networks and thus exert the effect against IS. This article reviews 107 papers published in recent years in PubMed, Chinese National Knowledge Infrastructure (CNKI), and WanFang Data in recent years. It has found that the activation factors of NLRP3 inflammasome include ROS, mitochondrial dysfunction, K⁺, Ca²⁺, lysosome rupture, and trans-Golgi breakdown. TLR4/NF-κB/NLRP3, ROS/TXNIP/NLRP3, AMPK/Nrf2/NLRP3, DRP1/NLRP3, TAK1/JNK/NLRP3 signaling pathways regulate the initiation and assembly of the NLRP3 inflammasome, subsequently induce pyroptosis, affecting the occurrence and development of IS. TCM can affect the above signaling pathways and regulate the pyroptosis mediated by NLRP3 inflammasome, so as to play a protective role against IS, which provides a new entry point for discussing the pathological mechanism of IS and a theoretical basis for developing TCM treasure house.

Britanin relieves ferroptosis-mediated myocardial ischaemia/reperfusion damage by upregulating GPX4 through activation of AMPK/GSK3β/Nrf2 signalling

CONTEXT

Ferroptosis was described as an important contributor to the myocardial ischaemia/reperfusion (MIR) injury, and britanin (Bri) was reported to exert antitumor and anti-inflammatory activities.

OBJECTIVE

Our study explores the effect and mechanism of Bri on MIR damage.

MATERIALS AND METHODS

The rat model of MIR was established by ligation of the left anterior descending coronary artery. Male Sprague-Dawley (SD) rats were divided into three groups: sham group (n = 6), MIR group (n = 6) and MIR + Bri group (n = 6; 50 mg/kg). Rats were intragastrically pre-treated with Bri or normal saline once daily for 3 days. To further verify the role and mechanism of Bri, H9C2 cells were subjected to hypoxia plus reoxygenation (H/R) to induce the in vitro model of MIR.

RESULTS

Compared with MIR rats, Bri significantly decreased infarct area (22.50% vs. 38.67%), myocardial apoptosis (23.00% vs. 41.5%), creatine phosphokinase (0.57 U/mL vs. 0.76 U/mL), and lactate dehydrogenase levels (3.18 U/mL vs. 5.17 U/mL), concomitant with alleviation of ferroptosis. Mechanistically, Bri treatment induced the activation of the adenosine monophosphate activated protein kinase (AMPK)/glycogen synthase kinase 3β (GSK3β)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in vivo. In addition, the AMPK/GSK3β/Nrf2 pathway participated in the regulation of glutathione peroxidase 4 (GPX4) expression, and silencing of Nrf2 attenuated the effect of Bri on H/R-induced cell injury.

DISCUSSION AND CONCLUSIONS

Bri protected against ferroptosis-mediated MIR damage by upregulating GPX4 through activation of the AMPK/GSK3β/Nrf2 signalling, suggesting that Bri might become a novel therapeutic agent for MIR.

A review of cardiovascular benefits of SGLT2 inhibitors

Sodium-glucose cotransporter 2 inhibitor (SGLT2I) is a new type of hypoglycemic drug that targets the kidney. As research continues to advance on this topic, it has been found that SGLT2I has multiple protective effects, such as hypoglycemic, cardio-renal protective, antihypertensive, and lipid-lowering effects. This review discusses the current concepts and possible mechanisms of SGLT2I in the treatment of heart failure, myocardial infarction, hypertension, cardiomyopathy and arrhythmia to provide a reference for clinicians to use drugs more reasonably and scientifically.

Salidroside attenuates myocardial ischemia/reperfusion injury via AMPK-induced suppression of endoplasmic reticulum stress and mitochondrial fission

Ischemic heart disease (IHD) is the primary cause of death worldwide. Salidroside (Sal), the major active compound derived from Rhodiola rosea, is believed to have cardioprotective effects. AMP-activated protein kinase (AMPK), is a pivotal AMP-activated protein kinase in energy metabolism. Whether Sal plays an anti-endoplasmic reticulum stress/mitochondrial fission role through AMPK remains elusive. In this study, we established a myocardial ischemia/reperfusion (I/R) rat model. Rat hearts exposed to Sal with or without compound C were then subjected to I/R. Further, H9c2 cardiomyocytes were subjected to simulated ischemia/reperfusion (SIR) by hypoxia-reoxygenation. The rats and cardiomyocytes were pretreated with Sal, followed by Compound C and AMPK-siRNA to block AMPK activity. We found that Sal significantly ameliorated cardiac function, mitigated infarct size and serum content of lactate dehydrogenase and creatine kinase, improved mitochondrial function, and reduced mitochondrial fission and apoptosis. Furthermore, in cultured H9c2 cardiomyocytes, Sal increased the cell viability and inhibited SIR-induced myocardial apoptosis and mitochondrial fission. Furthermore, the translocation of Drp1 from the cytoplasm to mitochondria induced by salidroside was confirmed both in vivo and in vitro. However, the use of Compound C or AMPK siRNA to block AMPK activity leads to blockade of the protective effects of Sal. In summary, protects against myocardial I/R by activating the AMPK signaling pathway, inhibiting ER stress, and reducing mitochondrial fission and apoptosis.

Prognostic Value of Modified Model for End-Stage Liver Disease Score in Patients Undergoing Isolated Tricuspid Valve Replacement

Objective

Though the prognostic value of the model for end-stage liver disease (MELD) score in tricuspid surgery was confirmed, the unstable international normalized ratio (INR) may affect the evaluation effectiveness of the MELD score for isolated tricuspid valve replacement (ITVR). The aim of the study was to assess the prognostic value of modified MELD for ITVR.

Methods and Results

A total of 152 patients who underwent ITVR were evaluated. The adverse outcome was defined as in-hospital mortality after surgery. The receiver operating characteristic (ROC) curve analysis demonstrated that a modified MELD score with albumin replacing INR (MELD-albumin) score presented well prognostic value [area under the curve (AUC) = 0.731, p = 0.006] for in-hospital mortality. Through Cox regression and further interval validation, the MELD-albumin score was identified as an independent predictor for in-hospital mortality. The optimal cutoff value of MELD-albumin was identified as 8.58 through maximally selected log-rank statistics. In addition, restricted cubic spline analysis demonstrated the linear inverse relationship between MELD-albumin and hazard ratio (HR) for in-hospital mortality. Kaplan–Meier analysis illustrated that in-hospital mortality was increased significantly in the high MELD-albumin (MELD-albumin ≥8.58) group than in the low MELD-albumin group (MELD-albumin <8.58; p < 0.001). Furthermore, high MELD-albumin was associated with lower body mass index (BMI), the incidence of lower extremities edema and moderate drinking history, and the MELD-albumin score was correlated with the value of aspartate transaminase (AST), alanine transaminase (ALT), and albumin. Furthermore, the incidence of renal failure (p = 0.003) and pulmonary infection (p = 0.042) was increased significantly in the high MELD-albumin group.

Conclusion

The MELD-albumin score could provide prognostic value for ITVR. In addition, the MELD-albumin score was useful in risk stratification and patient selection for patients with tricuspid regurgitation (TR) prior to ITVR.

Energy metabolism homeostasis in cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the general population. Energy metabolism disturbance is one of the early abnormalities in CVDs, such as coronary heart disease, diabetic cardiomyopathy, and heart failure. To explore the role of myocardial energy homeostasis disturbance in CVDs, it is important to understand myocardial metabolism in the normal heart and their function in the complex pathophysiology of CVDs. In this article, we summarized lipid metabolism/lipotoxicity and glucose metabolism/insulin resistance in the heart, focused on the metabolic regulation during neonatal and ageing heart, proposed potential metabolic mechanisms for cardiac regeneration and degeneration. We provided an overview of emerging molecular network among cardiac proliferation, regeneration, and metabolic disturbance. These novel targets promise a new era for the treatment of CVDs.

[8]-Gingerol exerts anti-myocardial ischemic effects in rats via modulation of the MAPK signaling pathway and L-type Ca2+ channels

Myocardial ischemia (MI) remains the leading cause of mortality worldwide. Therefore, it is urgent to seek the treatment to protect the heart. [8]‐Gingerol (8‐Gin), one of the most active ingredients in ginger, has antioxidant, cardiotonic, and cardiovascular protective properties. The present study elucidated the cardioprotection effects and underlying mechanisms of 8‐Gin in isoproterenol (ISO)‐induced MI. ISO (85 mg/kg/d) was subcutaneously injected for 2 consecutive days to induce acute MI model in rats. Electrocardiography, oxidative stress levels, calcium concentrations, and apoptosis degree were observed. The effects of 8‐Gin on L‐type Ca²⁺ current (I_Ca‐L), contraction, and Ca²⁺ transients were monitored in rat myocytes via patch‐clamp and IonOptix detection systems. 8‐Gin decreased J‐point elevation and heart rate and improved pathological heart damage. Moreover, 8‐Gin reduced the levels of CK, LDH, and MDA, ROS production, and calcium concentrations in myocardial tissue, while increased the activities of SOD, CAT, and GSH. In addition, 8‐Gin down‐regulated Caspase‐3 and Bax expressions, while up‐regulated Bcl‐2 expression. 8‐Gin produced a marked decrease in the expression of p38, JNK, and ERK1/2 proteins. 8‐Gin inhibited I_Ca‐L, cell contraction, and Ca²⁺ transients in isolated rat myocytes. The results indicate that 8‐Gin could exert anti‐myocardial ischemic effects, which may be associated with oxidative stress reduction, cardiomyocytes apoptosis inhibition through MAPK signaling pathway, and Ca²⁺ homeostasis regulation via I_Ca‐L modulation.

LncRNA Chaer Prevents Cardiomyocyte Apoptosis From Acute Myocardial Infarction Through AMPK Activation

Long non-coding RNA (lncRNA) is widely reported to be involved in cardiac (patho)physiology. Acute myocardial infarction, in which cardiomyocyte apoptosis plays an important role, is a life-threatening disease. Here, we report the lncRNA Chaer that is anti-apoptotic in cardiomyocytes during Acute myocardial infarction. Importantly, lncRNA Chaer is significantly downregulated in both oxygen-glucose deprivation (oxygen-glucose deprivation)-treated cardiomyocytes in vitro and AMI heart. In vitro, overexpression of lncRNA Chaer with adeno virus reduces cardiomyocyte apoptosis induced by OGD-treated while silencing of lncRNA Chaer increases cardiomyocyte apoptosis instead. In vivo, forced expression of lncRNA Chaer with AAV9 attenuates cardiac apoptosis, reduces infarction area and improves mice heart function in AMI. Interestingly, overexpression of lncRNA Chaer promotes the phosphorylation of AMPK, and AMPK inhibitor Compound C reverses the overexpression of lncRNA Chaer effect of reducing cardiomyocyte apoptosis under OGD-treatment. In summary, we identify the novel ability of lncRNA Chaer in regulating cardiomyocyte apoptosis by promoting phosphorylation of AMPK in AMI.

Isorhapontigenin protects against doxorubicin-induced cardiotoxicity via increasing YAP1 expression

As an effective anticancer drug, the clinical limitation of doxorubicin (Dox) is the time- and dose-dependent cardiotoxicity. Yes-associated protein 1 (YAP1) interacts with transcription factor TEA domain 1 (TEAD1) and plays an important role in cell proliferation and survival. However, the role of YAP1 in Dox-induced cardiomyopathy has not been reported. In this study, the expression of YAP1 was reduced in clinical human failing hearts with dilated cardiomyopathy and Dox-induced in vivo and in vitro cardiotoxic model. Ectopic expression of Yap1 significantly blocked Dox-induced cardiomyocytes apoptosis in TEAD1 dependent manner. Isorhapontigenin (Isor) is a new derivative of stilbene and responsible for a wide range of biological processes. Here, we found that Isor effectively relieved Dox-induced cardiomyocytes apoptosis in a dose-dependent manner in vitro. Administration with Isor (30 mg/kg/day, intraperitoneally, 3 weeks) significantly protected against Dox-induced cardiotoxicity in mice. Interestingly, Isor increased Dox-caused repression in YAP1 and the expression of its target genes in vivo and in vitro. Knockout or inhibition of Yap1 blocked the protective effects of Isor on Dox-induced cardiotoxicity. In conclusion, YAP1 may be a novel target for Dox-induced cardiotoxicity and Isor might be a new compound to fight against Dox-induced cardiotoxicity by increasing YAP1 expression.

Sestrin2 is an endogenous antioxidant that improves contractile function in the heart during exposure to ischemia and reperfusion stress

Sestrin2 (Sesn2) is a stress-inducible protein that plays a critical role in the response to ischemic stress. We recently recognized that Sesn2 may protect the heart against ischemic insults by reducing the generation of reactive oxygen species (ROS). After 45 min of ischemia followed by 24 h of reperfusion, myocardial infarcts were significantly larger in Sesn2 KO hearts than in wild-type hearts. Isolated cardiomyocytes from wild-type hearts treated with hypoxia and reoxygenation (H/R) stress showed significantly greater Sesn2 levels, compared with normoxic hearts (p < 0.05). Intriguingly, the administration of adeno-associated virus 9-Sesn2 into Sesn2 knockout (KO) hearts rescued Sesn2 protein levels and significantly improved the cardiac function of Sesn2 KO mice exposed to ischemia and reperfusion. The rescued levels of Sesn2 in Sesn2 KO hearts significantly ameliorated ROS generation and the activation of ROS-related stress signaling pathways during ischemia and reperfusion. Moreover, the rescued Sesn2 levels in Sesn2 KO cardiomyocytes improved the maximal velocity of cardiomyocyte shortening by H/R stress. Rescued Sesn2 levels also improved peak height, peak shortening amplitude, and maximal velocity of the re-lengthening of Sesn2 KO cardiomyocytes subjected to H/R. Finally, the rescued Sesn2 levels significantly augmented intracellular calcium levels and reduced the mean time constant of transient calcium decay in Sesn2 KO cardiomyocytes exposed to H/R. Overall, these findings indicated that Sesn2 can act as an endogenous antioxidant to maintain intracellular redox homeostasis under ischemic stress conditions.

Metformin-Enhanced Cardiac AMP-Activated Protein Kinase/Atrogin-1 Pathways Inhibit Charged Multivesicular Body Protein 2B Accumulation in Ischemia-Reperfusion Injury

Background: Cardiac autophagic flux is impaired during myocardial ischemia/reperfusion (MI/R). Impaired autophagic flux may exacerbate MI/R injury. Charged multivesicular body protein 2B (CHMP2B) is a subunit of the endosomal sorting complex required for transport (ESCRT-III) complex that is required for autophagy. However, the reverse role of CHMP2B accumulation in autophagy and MI/R injury has not been established. The objective of this article is to elucidate the roles of AMP-activated protein kinase (AMPK)/atrogin-1 pathways in inhibiting CHMP2B accumulation in ischemia-reperfusion injury. Methods: Male C57BL/6 mice (3-4 months) and H9c2 cardiomyocytes were used to evaluate MI/R and hypoxia/reoxygenation (H/R) injury in vivo and in vitro, respectively. MI/R was built by a left lateral thoracotomy and occluded the left anterior descending artery. H9c2 cells were firstly treated in 95% N2 and 5% CO2 for 15 h and reoxygenation for 1 h. Metformin (100 mg/kg/d) and CHMP2B (Ad-CHMP2B) transfected adenoviruses were administered to the mice. The H9c2 cells were treated with metformin (2.5 mM), MG-132 (10 μM), bafilomycin A1 (10 nM), and compound C (20 μM). Results: Autophagic flux was found to be inhibited in H/R-treated cardiomyocytes and MI/R mice, with elevated cardiac CHMP2B accumulation. Upregulated CHMP2B levels in the in vivo and in vitro experiments were shown to inhibit autophagic flux leading to the deterioration of H/R-cardiomyocytes and MI/R injury. This finding implies that CHMP2B accumulation increases the risk of myocardial ischemia. Metformin suppressed CHMP2B accumulation and ameliorated H/R-induced autophagic dysfunction by activating AMPK. Activated AMPK upregulated the messenger RNA expression and protein levels of atrogin-1, a muscle-specific ubiquitin ligase, in the myocardium. Atrogin-1 significantly enhanced the interaction between atrogin-1 and CHMP2B, therefore, promoting CHMP2B degradation in the MI/R myocardium. Finally, this study revealed that metformin-inhibited CHMP2B accumulation induced autophagic impairment and ischemic susceptibility in vivo through the AMPK-regulated CHMP2B degradation by atrogin-1. Conclusion: Impaired CHMP2B clearance in vitro and in vivo inhibits autophagic flux and weakens the myocardial ischemic tolerance. Metformin treatment degrades CHMP2B through the AMPK-atrogin-1-dependent pathway to maintain the homeostasis of autophagic flux. This is a novel mechanism that enriches the understanding of cardioprotection.

Sestrin 2, a potential star of antioxidant stress in cardiovascular diseases

Physiological reactive oxygen species (ROS) play an important role in cellular signal transduction. However, excessive ROS is an important pathological mechanism in most cardiovascular diseases (CVDs), such as myocardial aging, cardiomyopathy, ischemia/reperfusion injury (e.g., myocardial infarction) and heart failure. Programmed cell death, hypertrophy and fibrosis may be due to oxidative stress. Sestrin 2 (Sesn2), a stress-inducible protein associated with various stress conditions, is a potential antioxidant. Sesn2 can suppress the process of heart damage caused by oxidative stress, promote cell survival and play a key role in a variety of CVDs. This review discusses the effect of Sesn2 on the redox signal, mainly via participation in the signaling pathway of nuclear factor erythroid 2-related factor 2, activation of adenosine monophosphate-activated protein kinase and inhibition of mammalian target of rapamycin complex 1. It also discusses the effect of Sesn2's antioxidant activity on different CVDs. We speculate that Sesn2 plays an important role in CVDs by stimulating the process of antioxidation and promoting the adaptation of cells to stress conditions and/or the environment, opening a new avenue for related therapeutic strategies.

Heat shock protein 22 modulates NRF1/TFAM-dependent mitochondrial biogenesis and DRP1-sparked mitochondrial apoptosis through AMPK-PGC1α signaling pathway to alleviate the early brain injury of subarachnoid hemorrhage in rats

Mitochondrial dysfunction has been widely accepted as a detrimental factor in subarachnoid hemorrhage (SAH)-induced early brain injury (EBI), which is eminently related to poor neurologic function outcome. Previous studies have revealed that enhancement of heat shock protein 22 (hsp22) under conditions of stress is a friendly mediator of mitochondrial homeostasis, oxidative stress and apoptosis, thus accelerating neurological recovery. However, no study has confirmed whether hsp22 attenuates mitochondrial stress and apoptosis in the setting of SAH-induced EBI. Our results indicated that endogenous hsp22, p-AMPK/AMPK, PGC1α, TFAM, Nrf1 and Drp1 were significantly upregulated in cortical neurons in response to SAH, accompanied by neurologic impairment, brain edema, neuronal degeneration, lower level of mtDNA and ATP, mitochondria-cytosol translocation of cytochrome c, oxidative injury and caspase 3-involved mitochondrial apoptosis. However, exogenous hsp22 maintained neurological function, reduced brain edema, improved oxidative stress and mitochondrial apoptosis, these effects were highly dependent on PGC1α-related mitochondrial biogenesis/fission, as evidenced by co-application of PGC1α siRNA. Furthermore, we demonstrated that blockade of AMPK with dorsomorphin also compromised the neuroprotective actions of hsp22, along with the alterations of PGC1α and its associated pathway molecules. These data revealed that hsp22 exerted neuroprotective effects by salvaging mitochondrial function in an AMPK-PGC1α dependent manner, which modulates TFAM/Nrf1-induced mitochondrial biogenesis with positive feedback and DRP1-triggered mitochondrial apoptosis with negative feedback, further reducing oxidative stress and brain injury. Boosting the biogenesis and repressing excessive fission of mitochondria by hsp22 may be an efficient treatment to relieve SAH-elicited EBI.

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Hsp22 is notably upregulated in neurons at 24 h after SAH.

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Hsp22 boosts the NRF1/TFAM-dependent mitochondrial biogenesis.

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Hsp22 represses DRP1-sparked mitochondrial apoptosis.

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AMPK-PGC1α pathway is involved in hsp22-mediated neuroprotection after SAH.

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Modulation of mitochondrial biogenesis and fission may be efficient for treating SAH.

Research Progress on the Interaction Between Autophagy and Energy Homeostasis in Cardiac Remodeling

Cardiac remodeling is a common pathological process in various heart diseases, such as cardiac hypertrophy, diabetes-associated cardiomyopathy and ischemic heart diseases. The inhibition of cardiac remodeling has been suggested to be a potential strategy for preventing heart failure. However, the mechanisms involved in cardiac remodeling are quite complicated. Recent studies have reported a close correlation between autophagy and energy homeostasis in cardiac remodeling associated with various heart diseases. In this review, we summarize the roles of autophagy and energy homeostasis in cardiac remodeling and discuss the relationship between these two processes in different conditions to identify potential targets and strategies for treating cardiac remodeling by regulating autophagy.

Mechanosensing dysregulation in the fibroblast: A hallmark of the aging heart

The myofibroblast is a specialized fibroblast that expresses α-smooth muscle actin (α-SMA) and participates in wound contraction and fibrosis. The fibroblast to myofibroblast transition depends on chemical and mechanical signals. A fibroblast senses the changes in the environment (extracellular matrix (ECM)) and transduces these changes to the cytoskeleton and the nucleus, resulting in activation or inhibition of α-SMA transcription in a process called mechanosensing. A stiff matrix greatly facilitates the transition from fibroblast to myofibroblast, and although the aging heart is much stiffer than the young one, the aging fibroblast has difficulties in transitioning into the contractile phenotype. This suggests that the events occurring downstream of the matrix, such as activation or changes in expression levels of various proteins participating in mechanotransduction can negatively alter the ability of the aging fibroblast to become a myofibroblast. In this review, we will discuss in detail the changes in ECM, receptors (integrin or non-integrin), focal adhesions, cytoskeleton, and transcription factors involved in mechanosensing that occur with aging.

Circular RNA Involved in the Protective Effect of Malva sylvestris L. on Myocardial Ischemic/Re-Perfused Injury

Ischemic heart disease has become a major health challenge worldwide. Malva sylvestris L. (MS) is a traditional herbal medicine with anti-inflammatory properties and have been used as antioxidant and anti- inflammatory agent in infectious diseases and inflammatory diseases.In this study, we aimed at elucidating the mechanism of MS against ischemia-reperfusion (I/R)–induced injury in vivo and in vitro. The I/R animal model in rats and oxygen glucose deprivation/re-oxygenation (OGD/Re) model in H9c2 cells were used in this study. MS was used to pre-treat the rats and cells. Electrocardiogram, histology staining, qPCR, ELISA, CCK-8, and circRNA microarray were performed. We found that pre-treatment with MS extract attenuate OGD/Re-induced cell apoptosis and cell viability inhibition in H9c2 cells. In addition, pre-treatment with MS protected against I/R injury in vivo. The protective effects of MS pre-treatment were associated with inflammatory genes expression and cytokines release. Further mechanistic investigation revealed that MS protected cardiomyocytes through regulating circular RNA (circRNA). We identified a novel circRNA circ003593 that mediated the protective role of MS in vitro through NLRP3 complex, which was associated with reperfusion injury salvage kinase (RISK) signaling pathway. Conclusion: this study is the first time to demonstrate the protective role of MS on I/R injury. Our findings reveal a novel circRNA circ003593-mediated the protective role of MS through NLRP3 inflammasome. Circ003593 may serve as a potential therapeutic target for ischemic heart diseases.

Effects of Different Exercise Interventions on Cardiac Function in Rats With Myocardial Infarction

BACKGROUND

High-intensity interval training (HIIT) and aerobic training (AT) both improve cardiac function; however, their effects on cardiac function after myocardial infarction (MI) and the molecular mechanisms are unclear. In this study, HIIT, AT and sedentary (SED) interventions were performed for 4 weeks to compare the effects on cardiac function after MI and explore a more suitable approach for clinical application and the potential mechanisms.

METHODS

Twenty-four (24) male rats were randomly divided into a control group (CON), MI-sedentary group (MI-SED), MI-aerobic training group (MI-AT), and MI-high-intensity interval training group (MI-HIIT). After 4 weeks of intervention the exercise capacity, heart rate (HR), left ventricular end-diastolic diameter (LVEDD), left ventricular end systolic diameter (LVESD), left ventricular ejection fraction (LVEF), AMP-activated protein kinase α1 (AMPKα1), cardiomyocyte morphology, and cardiac mitochondria were assessed.

RESULTS

After intervention: 1) exercise capacity in the MI-AT (49.08±3.141 m; p<0.001) and MI-HIIT (51.70±7.572 m; p<0.001) groups was significantly more increased than the MI-SED group; there was no significant difference between the MI-AT and MI-HIIT group (p=0.33). 2) LVEDD and LVESD in the MI-SED (p<0.01) and MI-HIIT (p<0.01) groups was significantly more increased than the CON group; the MI-AT group showed no significant difference in LVEDD and LVESD compared with the CON group; LVEF in the MI-AT (53.47±7.913%; p=0.03) and MI-HIIT (56.20±7.224%; p=0.006) groups was significantly more increased than the MI-SED group, and there was no statistical difference between the MI-AT and MI-HIIT groups. 3) AMPKα1 expression was significantly increased in the MI-AT (1.15±0.264; p=0.001) and MI-HIIT (1.04±0.238; p=0.003) groups and decreased in the MI-SED group (0.71±0.257; p<0.001) when compared with the CON group. 4) The MI-SED group exhibited sarcoplasmic dissolution and fibrous hyperplasia in the myocardium, cardiac mitochondrial damage and reduced mitochondrial numbers; the MI-HIIT group displayed swollen and vacuolated cardiac mitochondria with disrupted cristae; the MI-AT and MI-HIIT groups had significantly increased cardiac mitochondrial numbers than the MI-SED group; there was no statistical difference between the MI-AT and MI-HIIT groups.

CONCLUSIONS

Aerobic training and HIIT for 4 weeks had similar cardioprotection and were superior to SED intervention. Both AT and HIIT improved cardiac function and exercise capacity by upregulating AMPKα1 expression. However, 4 weeks of intervention resulted in left ventricular dilation and cardiac myocardial mitochondrial injury in the MI-HIIT group.

GLP-1 receptor agonist liraglutide protects cardiomyocytes from IL-1β-induced metabolic disturbance and mitochondrial dysfunction

Cardiac inflammation plays a critical role in the development of heart failure. Inflammation-induced oxidative stress contributes to aberrant cardiac metabolism and mitochondrial function. GLP-1 receptor agonists (GLP-1 RAs) are a type of blood glucose-lowering agent typically used in the treatment of type 2 diabetes. Recent studies have convincingly shown that GLP-1 RAs possess beneficial effects in diabetes-related cardiovascular complications. Liraglutide is a commonly used long-acting agonist that shows promising cardioprotective benefits. In this study, we investigated the protective role of Liraglutide in cultured cardiomyocytes. We found that HL-1 cardiomyocytes moderately expressed the GLP-1 receptor, and co-treatment with Liraglutide ameliorated IL-1β-induced cellular ROS production and NADPH oxidase (NOX)-4 expression. Furthermore, we found that Liraglutide protected cardiomyocytes from IL-1β-induced decreased mitochondrial membrane potential and reduced ATP production. Seahorse analysis revealed that Liraglutide mitigated IL-1β-induced reduced basal and maximum respiration rates as well as spare respiration capacity. Additionally, we found that Liraglutide alleviated IL-1β-induced aberrant triglyceride accumulation and adiponectin secretion. Mechanistically, we showed that Liraglutide ameliorated IL-1β-induced phosphorylation of AMPK and ACC as well as the reduction in PGC-1α, CPT-1, and DGAT1. Finally, through the study we demonstrated that the blockage of AMPK activity by Compound C abolished the ameliorative effect of Liraglutide on IL-1β-induced repressed ATP production and triglyceride accumulation, indicating that the action of Liraglutide was dependent on AMPK activation. In conclusion, this study revealed the molecular mechanism of Liraglutide protection in cultured cardiomyocytes. The GLP-1 RA Liraglutide could have therapeutic implications by modulating cardiac inflammation.

Sestrin 2 controls the cardiovascular aging process via an integrated network of signaling pathways

As an inevitable biological process, cardiovascular aging is the greatest risk factor for cardiovascular diseases (CVDs). Sestrin 2 (Sesn2), a stress-inducible and age-related protein associated with various stress conditions, plays a pivotal role in slowing this process. It acts as an anti-aging agent, mainly through its antioxidant enzymatic activity and regulation of antioxidant signaling pathways, as well as by activating adenosine monophosphate-activated protein kinase and inhibiting mammalian target of rapamycin complex 1. In this review, we first introduce the biochemical functions of Sesn2 in the cardiovascular aging process, and describe how Sesn2 expression is regulated under various stress conditions. Next, we emphasize the role of Sesn2 signal transduction in a series of age-related CVDs, including hypertension, myocardial ischemia and reperfusion, atherosclerosis, and heart failure, as well as provide potential mechanisms for the association of Sesn2 with CVDs. Finally, we present the potential therapeutic applications of Sesn2-directed therapy and future prospects.

Irisin attenuates myocardial ischemia/reperfusion-induced cardiac dysfunction by regulating ER-mitochondria interaction through a mitochondrial ubiquitin ligase-dependent mechanism

BACKGROUND

Myocardial ischemia/reperfusion (MI/R) injury imposes devastating cardiovascular sequelae in particular cardiac dysfunction as a result of restored blood flow. However, the mechanism behind MI/R injury remains elusive. Mitochondrial ubiquitin ligase (MITOL/MARCH5) is localized at the mitochondria-ER contact site and may be activated in response to a variety of pathophysiological processes, such as apoptosis, mitochondrial injury, ER stress, hypoxia, and reactive oxygen species (ROS) generation. Irisin as a cleaved product of fibronectin type III domain-containing protein 5 (FNDC5) displays cardioprotection in diverse cardiac diseases.

METHODS

This study was designed to examine the role of irisin and MITOL in MI/R injury. Male C57BL/6J mice (8-10-week-old) were administered adenovirus MITOL shRNA through intracardiac injection followed by MI/R surgery through ligation and release the slipknot of cardiac left anterior descending coronary artery.

RESULTS

Our results showed that irisin improved myocardial function in the face of MI/R injury as evidenced by reduced myocardial infarct size, apoptotic rate, serum lactate dehydrogenase (LDH), ROS generation, and malondialdehyde (MDA) levels as well as lessened ER stress injury. Moreover, our results indicated that protective role of irisin was mediated by upregulation of MITOL. Irisin also protected H9c2 cells against simulated I/R through negating ER stress, apoptosis, ROS and MDA levels, as well as facilitating superoxide dismutase (SOD) by way of elevated MITOL expression.

CONCLUSIONS

To this end, our data favored that irisin pretreatment protects against MI/R injury, ER stress, ROS production, and mitochondrial homeostasis through upregulation of MITOL. These findings depicted the therapeutic potential of irisin and MITOL in the management of MI/R injury in patients with ST-segment elevation.

Prognostic value of serum albumin-to-creatinine ratio in patients with acute myocardial infarction: Results from the retrospective evaluation of acute chest pain study

The long-term association between serum albumin-to-creatinine ratio (sACR) and poor patient outcomes in acute myocardial infarction (AMI) remains unclear. This study aimed to determine whether sACR was a predictor of poor long-term survival in patients with AMI.This was a study of patients with AMI in the emergency department (ED) from the retrospective multicenter study for early evaluation of acute chest pain (REACP) study. The patients were categorized into tertiles (T1, T2, and T3) based on the admission sACR (0.445 and 0.584 g/μmol). Baseline sACR at admission to the ED was predictive of adverse outcomes. The primary outcome was all-cause mortality within the follow-up period. Cox proportional hazards models were performed to investigate the association between sACR and all-cause mortality in patients with AMI.A total of 2250 patients with AMI were enrolled, of whom 229 (10.2%) died within the median follow-up period of 10.7 (7.2-14.6) months. Patients with a lower sACR had higher all-cause mortality and adverse outcomes rates than patients with a higher sACR. Kaplan-Meier survival analysis showed that patients with a higher sACR had a higher cumulative survival rate (P < .001). Cox regression analysis showed that a decreased sACR was an independent predictor of all-cause mortality [T2 vs T1: hazard ratio (HR); 0.550, 95% confidence interval (95% CI), 0.348-0.867; P = .010 and T3 vs T1: HR, 0.305; 95% CI, 0.165-0.561; P < .001] and cardiac mortality (T2 vs T1: HR, 0.536; 95% CI, 0.332-0.866; P = .011 and T3 vs T1: HR, 0.309; 95% CI, 0.164-0.582, P < .001).The sACR at admission to ED was independently associated with adverse outcomes, indicating that baseline sACR was a useful biomarker to identify high-risk patients with AMI at an early phase in ED.

Emerging Roles and Therapeutic Interventions of Aerobic Glycolysis in Glioma

Glioma is the most common type of intracranial malignant tumor, with a great recurrence rate due to its infiltrative growth, treatment resistance, intra- and intertumoral genetic heterogeneity. Recently, accumulating studies have illustrated that activated aerobic glycolysis participated in various cellular and clinical activities of glioma, thus influencing the efficacy of radiotherapy and chemotherapy. However, the glycolytic process is too complicated and ambiguous to serve as a novel therapy for glioma. In this review, we generalized the implication of key enzymes, glucose transporters (GLUTs), signalings and transcription factors in the glycolytic process of glioma. In addition, we summarized therapeutic interventions via the above aspects and discussed promising clinical applications for glioma.

MTMR14 protects against hepatic ischemia-reperfusion injury through interacting with AKT signaling in vivo and in vitro

Hepatic ischemia-reperfusion (IR) injury is characterized by severe inflammation and cell death. However, very few effective therapies are presently available for hepatic IR injury treatment. Here, we reported a protective function and the underlying mechanism of myotubularin-related protein 14 (MTMR14) during hepatic IR injury. Hepatocyte-specific MTMR14 knockout (HKO) and transgenic (TG) mice were subjected to hepatic IR operation to explore MTMR14 function in vivo. Primary hepatocytes isolated from MTMR14-HKO and MTMR14-TG mice were subjected to hypoxia/reoxygenation (HR) insult in vitro. We found that MTMR14 expression in liver tissues from individuals with hepatic IR was markedly decreased, and similar results were detected in mice with hepatic IR surgery. MTMR14-TG mice following hepatic IR operation had obviously ameliorated liver pathological changes, along with improved hepatic dysfunction, which was proved by the decreased serum alanine amino transferase (ALT) and aspartate amino transferase (AST) levels. MTMR14-HKO and MTMR14-TG animal models indicated that MTMR14 alleviated cell death and inflammatory response. In addition, MTMR14 inhibited nuclear transcription factor κB (NF-κB) signaling. Of note, promoting MTMR14 expression improved phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) pathway through a physical interaction with AKT, subsequently reducing cell death and inflammation. Therefore, MTMR14 is a protective factor during hepatic IR injury, and the MTMR14/AKT signaling is involved the pathogenesis hepatic IR injury. Improvement of this axis might be a novel therapeutic strategy for the prevention of this pathological process.

Wnt signaling pathway in aging-related tissue fibrosis and therapies

Fibrosis is the final hallmark of pathological remodeling, which is a major contributor to the pathogenesis of various chronic diseases and aging-related organ failure to fully control chronic wound-healing and restoring tissue function. The process of fibrosis is involved in the pathogenesis of the kidney, lung, liver, heart and other tissue disorders. Wnt is a highly conserved signaling in the aberrant wound repair and fibrogenesis, and sustained Wnt activation is correlated with the pathogenesis of fibrosis. In particular, mounting evidence has revealed that Wnt signaling played important roles in cell fate determination, proliferation and cell polarity establishment. The expression and distribution of Wnt signaling in different tissues vary with age, and these changes have key effects on maintaining tissue homeostasis. In this review, we first describe the major constituents of the Wnt signaling and their regulation functions. Subsequently, we summarize the dysregulation of Wnt signaling in aging-related fibrotic tissues such as kidney, liver, lung and cardiac fibrosis, followed by a detailed discussion of its involvement in organ fibrosis. In addition, the crosstalk between Wnt signaling and other pathways has the potential to profoundly add to the complexity of organ fibrosis. Increasing studies have demonstrated that a number of Wnt inhibitors had the potential role against tissue fibrosis, specifically in kidney fibrosis and the implications of Wnt signaling in aging-related diseases. Therefore, targeting Wnt signaling might be a novel and promising therapeutic strategy against aging-related tissue fibrosis.

Impact of PRECISE-DAPT and DAPT Scores on Dual Antiplatelet Therapy Duration After 2nd Generation Drug-Eluting Stent Implantation

PURPOSE

Determining the optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an important clinical issue. We evaluated the effects of ischemia (by DAPT score) and bleeding (by PRECISE-DAPT score), as well as the impact of DAPT duration, on clinical outcomes.

METHODS

From pooled analysis of four randomized clinical trials, 5131 patients undergoing second-generation DES implantation were randomized to short-duration (n = 2575; ≤ 6 months) or standard-duration (n = 2556; ≥ 12 months) DAPT groups. This population was further divided into four subgroups according to PRECISE-DAPT (high bleeding risk ≥ 25) and DAPT (high ischemic risk ≥ 2) scores.

RESULTS

Net clinical outcomes (1.3% vs. 1.3%; p = 0.89) and ischemic events (5.0% vs. 4.5%; p = 0.44) did not differ between the two duration groups, although bleeding events were more frequent in patients with standard-duration DAPT (0.4% vs. 0.9%; p = 0.04). Standard-duration DAPT was associated with fewer ischemic events (6.9% vs. 4.0%; p = 0.02) and no increase in bleeding events only among patients at low bleeding risk and high ischemic risk. The other groups show no differences in net clinical outcomes, ischemic events, or bleeding events according to DAPT duration.

CONCLUSION

Compared with short-duration DAPT, standard-duration DAPT was associated with similar net clinical outcomes and ischemic events, but more bleeding events at 12 months after second-generation DES implantation. However, standard-duration DAPT reduced ischemic events without increasing bleeding events among patients at low bleeding and high ischemic risk. When determining DAPT duration, considering both ischemic and bleeding risk can help optimize patient benefits.

CLINICAL TRIAL REGISTRATION

EXCELLENT (NCT00698607), RESET (NCT01145079), IVUS-XPL (NCT01308281), OPTIMA-C (NCT03056118).

miR‑320‑3p is involved in morphine pre‑conditioning to protect rat cardiomyocytes from ischemia/reperfusion injury through targeting Akt3

Morphine pre-conditioning (MPC) can significantly reduce myocardial ischemic injury and inhibit cardiomyocyte apoptosis, but the underlying mechanism still remains unclear. The aim of the present study was to investigate the protective mechanism of MPC in myocardial hypoxia/reoxygenation (H/R) injury at the microRNA (miR) level. H9c2 cells were used as a model of H/R and subjected to morphine pre-treatment. The protective effects of MPC on H/R injury in cardiomyocytes were evaluated using MTT and colorimetric assay, as well as flow cytometry. In addition, reverse transcription-quantitative PCR, western blotting and dual-luciferase reporter assay experiments were performed to determine the relationship between MPC, miR-320-3p and Akt3, and their effects on H/R injury. The present study demonstrated that MPC enhanced cell activity, decreased LDH content, and reduced apoptosis in rat cardiomyocytes, suggesting that MPC could protect these cells from H/R injury. Moreover, MPC partially reversed the increase in miR-320-3p expression and the decrease in Akt3 levels caused by H/R injury. Inhibition of miR-320-3p expression also attenuated the effects of H/R on cardiomyocyte activity, LDH content and apoptosis. Furthermore, Akt3 was predicted to be a target gene of miR-320-3p, and overexpression of miR-320-3p inhibited the expression of Akt3, blocking the protective effects of MPC on the cells. The current findings revealed that MPC could protect cardiomyocytes from H/R damage through targeting miR-320-3p to regulate the PI3K/Akt3 signaling pathway.

Cardiomyocyte ageing and cardioprotection: consensus document from the ESC working groups cell biology of the heart and myocardial function

Advanced age is a major predisposing risk factor for the incidence of coronary syndromes and comorbid conditions which impact the heart response to cardioprotective interventions. Advanced age also significantly increases the risk of developing post-ischaemic adverse remodelling and heart failure after ischaemia/reperfusion (IR) injury. Some of the signalling pathways become defective or attenuated during ageing, whereas others with well-known detrimental consequences, such as glycoxidation or proinflammatory pathways, are exacerbated. The causative mechanisms responsible for all these changes are yet to be elucidated and are a matter of active research. Here, we review the current knowledge about the pathophysiology of cardiac ageing that eventually impacts on the increased susceptibility of cells to IR injury and can affect the efficiency of cardioprotective strategies.

Inhibition of Dectin-1 in mice ameliorates cardiac remodeling by suppressing NF-κB/NLRP3 signaling after myocardial infarction

The myocardial inflammatory response is a consequence of myocardial infarction (MI), which may deteriorate cardiac remodeling and lead to dysfunction in the heart post-MI. Dectin-1 is a c-type lectin, which has been shown to regulate innate immune responses to pathogens. However, the role of Dectin-1 in the heart diseases remains largely unknown. In this study, we aimed to investigate the effects of Dectin-1 on cardiac remodeling post-MI. We found that cardiac Dectin-1 mRNA and protein expressions were significantly elevated in C57BL/6 mice after MI. In vitro, hypoxia induced cardiomyocyte injury in parallel with increased Dectin-1 protein expression. Knockdown of Dectin-1 remarkably attenuated cardiomyocyte death under hypoxia and lipopolysaccharide (LPS) stimulation. In vivo administration of adeno-associated virus serotype 9 mediated silencing of Dectin-1, which significantly decreased cardiac fibrosis, dilatation, and improved cardiac function in the mice post-MI. At the molecular level, downregulation of Dectin-1 dramatically suppressed up-regulation of nuclear factor-κB (NF-κB), nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3), and the inflammatory genes involved in fibrogenesis and cardiac remodeling after MI. Furthermore, treatment with BAY11-7082, an inhibitor of NF-κB, repressed the activation of NF-κB, and attenuated LPS induced elevation of NLRP3 and cell death in cardiomyocytes. Collectively, upregulation of Dectin-1 in cardiomyocytes post-MI contributes to cardiac remodeling and cardiac dysfunction at least partially by activating NF-κB and NLRP3. This study identified Dectin-1 as a promising therapeutic target for ischemic heart disease.

MicroRNA-21 mediates the protective effects of salidroside against hypoxia/reoxygenation-induced myocardial oxidative stress and inflammatory response

Myocardial ischemia-reperfusion (I/R) injury is the oxidative stress and inflammatory response that occurs when a tissue is reperfused following a prolonged period of ischemic injury. Growing evidence has demonstrated that microRNAs (miRs) are essential in the development of myocardial I/R injury. Salidroside, a phenylpropanoid glycoside isolated from a traditional Chinese medicinal plant, Rhodiola rosea, possesses multiple pharmacological functions and protects against myocardial I/R injury in vitro and in vivo. However, the role of miRs in the cardioprotective effects of salidroside against myocardial I/R injury has not been studied, to the best of our knowledge. In the present study, the role of miR21 in the underlying mechanism of salidroside-induced protection against oxidative stress and inflammatory injuries in hypoxia/reoxygenation (H/R)-treated H9c2 cardiomyocytes was determined. The cell viability was assessed with an MTT assay. Lactate dehydrogenase (LDH) release, caspase-3 activity, malondialdehyde (MDA) level, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were determined by commercial kits. Cell apoptosis was measured by flow cytometry. Intracellular reactive oxygen species (ROS) generation was monitored by DCFH-DA. The miR-21 level was quantified by reverse transcription-quantitative (RT-q)PCR. The interleukin (IL)-6, IL-1β and tumor necrosis factor (TNF)-α levels were measured by RT-qPCR and ELISA. The results showed that salidroside pretreatment significantly increased cell viability and decreased the release of LDH, accompanied by an increase in miR-21 expression in H/R-treated H9c2 cells and a miR-21 inhibitor reversed these effects. In addition, the miR-21 inhibitor also abrogated the inhibition of salidroside on H/R-induced increases in apoptosis and caspase-3 activity in H9c2 cells. Salidroside mitigated H/R-induced oxidative stress as illustrated by the downregulation of ROS generation and MDA level and increased the activities of the antioxidant enzymes, SOD and GSH-Px, all of which were abrogated in cells transfected with the miR-21 inhibitor. Salidroside induced a decrease in the expression and levels of the pro-inflammatory cytokines, IL-6, IL-1β and TNF-α, which were prevented by the miR-21 inhibitor. Together, these results provide evidence of the beneficial effects of salidroside against myocardial I/R injury by reducing myocardial oxidative stress and inflammation which are enhanced by increasing miR-21 expression.

D-dimer and diffusion-weighted imaging pattern as two diagnostic indicators for cancer-related stroke: A case-control study based on the STROBE guidelines

The aim of this study was to evaluate the risk factors and elucidate the clinical characteristics of cancer-associated ischemic stroke to differentiate it from conventional ischemic stroke in China and East Asia. Between June 2012 and June 2016, a retrospective analysis was performed on 609 stroke patients with cancer. They were divided into 3 groups: cancer-stroke group (CSG, 203 cases), stroke group (SG, 203 cases), and cancer group (CG, 203 cases). The D-dimer levels and diffusion-weighted imaging lesion (DWI) pattern were compared to an age- and sex-matched control group. The most common cancer types were colorectal cancer (20.2%) and lung cancer (18.72%). The average D-dimer level in stroke patients and cancer patients were 0.34 and 1.50 mg/L, respectively. The descending levels of D-dimer from cancer types were lung cancer (2.06 mg/L), pancreas (1.74 mg/L), gastric (1.61 mg/L), among others. Univariate analysis of the CSG and the others shows there were significant differences in the prevalence of the levels of D-dimer and DWI pattern, hypertension, diabetes mellitus, and thrombus. CSG has a unique pathological characteristic including high plasma D-dimer levels and multiple vascular lesions. The results show that D-dimer and DWI can be used as diagnostic index in clinical practice.

An Update on the Multifaceted Roles of STAT3 in the Heart

Signal transducer and activator of transcription 3 (STAT3) is a signaling molecule and transcription factor that plays important protective roles in the heart. The protection mediated by STAT3 is attributed to its genomic actions as a transcription factor and other non-genomic roles targeting mitochondrial function and autophagy. As a transcription factor, STAT3 upregulates genes that are anti-oxidative, anti-apoptotic, and pro-angiogenic, but suppresses anti-inflammatory and anti-fibrotic genes. Its suppressive effects on gene expression are achieved through competing with other transcription factors or cofactors. STAT3 is also linked to the modification of mRNA expression profiles in cardiac cells by inhibiting or inducing miRNA. In addition to these genomic roles, STAT3 is suggested to function protectively in mitochondria, where it regulates ROS production, in part by regulating the activities of the electron transport chain complexes, although our recent evidence calls this role into question. Nonetheless, STAT3 is a key player known to be activated in the cardioprotective ischemic conditioning protocols. Through these varied roles, STAT3 participates in various mechanisms that contribute to cardioprotection against different heart pathologies, including myocardial infarction, hypertrophy, diabetic cardiomyopathy, and peripartum cardiomyopathy. Understanding how STAT3 is involved in the protective mechanisms against these different cardiac pathologies could lead to novel therapeutic strategies to treat them.

AMPK: a balancer of the renin-angiotensin system

The renin-angiotensin system (RAS) is undisputedly well-studied as one of the oldest and most critical regulators for arterial blood pressure, fluid volume, as well as renal function. In recent studies, RAS has also been implicated in the development of obesity, diabetes, hyperlipidemia, and other diseases, and also involved in the regulation of several signaling pathways such as proliferation, apoptosis and autophagy, and insulin resistance. AMP-activated protein kinase (AMPK), an essential cellular energy sensor, has also been discovered to be involved in these diseases and cellular pathways. This would imply a connection between the RAS and AMPK. Therefore, this review serves to draw attention to the cross-talk between RAS and AMPK, then summering the most recent literature which highlights AMPK as a point of balance between physiological and pathological functions of the RAS.

Loss of Rubicon ameliorates doxorubicin-induced cardiotoxicity through enhancement of mitochondrial quality

BACKGROUND

The therapeutic potential of doxorubicin (DOX) is limited by cardiotoxicity. Rubicon is an inhibitory interacting partner of autophagy protein UVRAG. Currently, the role of Rubicon in DOX-induced cardiotoxicity is unknown. In this study, we test the hypothesis that loss of Rubicon attenuates DOX-induced cardiotoxicity.

METHODS

A mouse model of acute DOX-induced cardiotoxicity was established by a single intraperitoneal injection of DOX at a dose of 20 mg/kg. Rubicon expression was detected by Western blot. Cardiac damage was determined by measuring activities of lactate dehydrogenase and myocardial muscle creatine kinase in the serum, cytoplasmic vacuolization, collagen deposition, ROS levels, ATP content and mitochondrial damage in the heart. Cardiac morphometry and function were assessed by echocardiography. Markers for autophagy, mitophagy and mitochondrial dynamics were evaluated by Western blot and real time reverse transcription polymerase chain reaction.

RESULTS

Rubicon expression was reduced in the heart 16 h after DOX treatment. DOX induced accumulation of cytoplasmic vacuolization and collagen, increased serum activities of lactate dehydrogenase and myocardial muscle creatine kinase, enhanced ROS levels, reduced ATP content, pronounced mitochondrial damage and greater left ventricular wall thickness in wild type mice, which were mitigated by Rubicon deficiency. Mechanistically, loss of Rubicon improved DOX-induced impairment of autophagic flux, Parkin-mediated mitophagy and mitochondrial fission and fusion in the heart.

CONCLUSIONS

Loss of Rubicon ameliorates DOX-induced cardiotoxicity through enhancement of mitochondrial quality by improving autophagic flux, mitophagy and mitochondrial dynamics. Rubicon is a potential molecular target for prevention and therapy of DOX cardiotoxicity.

LncRNA: Shedding light on mechanisms and opportunities in fibrosis and aging

Fibrosis is universally observed in multiple aging-related diseases and progressions and is characterized by excess accumulation of the extracellular matrix. Fibrosis occurs in various human organs and eventually results in organ failure. Noncoding RNAs (ncRNAs) have emerged as essential regulators of cellular signaling and relevant human diseases. In particular, the enigmatic class of long noncoding RNAs (lncRNAs) is a kind of noncoding RNA that is longer than 200 nucleotides and does not possess protein coding ability. LncRNAs have been identified to exert both promotive and inhibitory effects on the multifaceted processes of fibrosis. A growing body of studies has revealed that lncRNAs are involved in fibrosis in various organs, including the liver, heart, lung, and kidney. As lncRNAs have been increasingly identified, they have become promising targets for anti-fibrosis therapies. This review systematically highlights the recent advances regarding the roles of lncRNAs in fibrosis and sheds light on the use of lncRNAs as a potential treatment for fibrosis.

Roles of forkhead box O (FoxO) transcription factors in neurodegenerative diseases: A panoramic view

Neurodegenerative diseases (NDDs), which are among the most important aging-related diseases, are typically characterized by neuronal damage and a progressive impairment in neurological function during aging. Few effective therapeutic targets for NDDs have been revealed; thus, an understanding of the pathogenesis of NDDs is important. Forkhead box O (FoxO) transcription factors have been implicated in the mechanisms regulating aging and longevity. The functions of FoxOs are regulated by diverse post-translational modifications (e.g., phosphorylation, acetylation, ubiquitination, methylation and glycosylation). FoxOs exert both detrimental and protective effects on NDDs. Therefore, an understanding of the precise function of FoxOs in NDDs will be helpful for developing appropriate treatment strategies. In this review, we first introduce the post-translational modifications of FoxOs. Next, the regulation of FoxO expression and post-translational modifications in the central nervous system (CNS) is described. Afterwards, we analyze and address the important roles of FoxOs in NDDs. Finally, novel potential directions of future FoxO research in NDDs are discussed. This review recapitulates essential facts and questions about the promise of FoxOs in treating NDDs, and it will likely be important for the design of further basic studies and to realize the potential for FoxOs as therapeutic targets in NDDs.

Paeoniflorin protects against intestinal ischemia/reperfusion by activating LKB1/AMPK and promoting autophagy

Intestinal ischemia-reperfusion (I/R) injury is a common pathological process with high clinical morbidity and mortality. Paeoniflorin, a monoterpene glucoside, is found to have diverse health beneficial effects including autophagy modulation, anti-inflammatory, anti-apoptotic, and anti-oxidative effects. Based on our pre-experiments, we proposed that paeoniflorin could ameliorate intestinal I/R injury and restore autophagy through activating LKB1/AMPK signal pathway. Our proposal was verified using rat intestinal I/R model in vivo and intestinal epithelial cell line (IEC-6 cells) hypoxia/reoxygenation (H/R) model in vitro. Our results showed that paeoniflorin pretreatment exerted protective effects in rat intestinal I/R injury by reducing intestinal morphological damage, inflammation, oxidative stress, and apoptosis. Paeoniflorin restored H/R-impaired autophagy flux by up-regulating autophagy-related protein p62/SQSTM1 degradation, LC3II and beclin-1 expression, and autophagosomes synthesis without significantly affecting control IEC-6 cells. Paeoniflorin pretreatment significantly activated LKB1/AMPK signaling pathway by reversing the decreased LKB1 and AMPK phosphorylation without affecting total LKB1 both in vivo and in vitro. LKB1 knockdown reduced AMPK phosphorylation, suppressed LC3II and Beclin-1 level, and decreased the degradation of SQSTM/p62, and the knockdown weakened the effects of paeoniflorin in restoring the impaired autophagy flux in H/R injured IEC-6 cells, suggesting that paeoniflorin mitigated the intestinal I/R-impaired autophagy flux by activating LKB1/AMPK signaling pathway. Our study may provide valuable information for further studies.