Molecular mechanisms of apoptosis in the cardiac myocyte

Cardiac surgery-Associated acute kidney injury - A narrative review

Cardiac Surgery-Associated Acute Kidney Injury (CSA-AKI) is a serious complication seen in approximately 20-30% of cardiac surgery patients. The underlying pathophysiology is complex, often involving both patient- and procedure related risk factors. In contrast to AKI occurring after other types of major surgery, the use of cardiopulmonary bypass comprises both additional advantages and challenges, including non-pulsatile flow, targeted blood flow and pressure as well as the ability to manipulate central venous pressure (congestion). With an increasing focus on the impact of CSA-AKI on both short and long-term mortality, early identification and management of high-risk patients for CSA-AKI has evolved. The present narrative review gives an up-to-date summary on definition, diagnosis, underlying pathophysiology, monitoring and implications of CSA-AKI, including potential preventive interventions. The review will provide the reader with an in-depth understanding of how to identify, support and provide a more personalized and tailored perioperative management to avoid development of CSA-AKI.

In Vivo Stable Allogenic Cartilage Regeneration in a Goat Model Based on Immunoisolation Strategy Using Electrospun Semipermeable Membranes

Tissue engineering is a promising strategy for cartilage defect repair. However, autologous cartilage regeneration is limited by additional trauma to the donor site and a long in vitro culture period. Alternatively, allogenic cartilage regeneration has attracted attention because of the unique advantages of an abundant donor source and immediate supply, but it will cause immune rejection responses (IRRs), especially in immunocompetent large animals. Therefore, a universal technique needs to be established to overcome IRRs for allogenic cartilage regeneration in large animals. In the current study, a hybrid synthetic-natural electrospun thermoplastic polyurethane/gelatin (TPU/GT) semipermeable membrane to explore the feasibility of stable allogenic cartilage regeneration by an immunoisolation strategy is developed. In vitro results demonstrated that the rationally designed electrospun TPU/GT membranes has ideal biocompatibility, semipermeability, and an immunoisolation function. In vivo results further showed that the semipermeable membrane (SPM) efficiently blocked immune cell attack, decreased immune factor production, and cell apoptosis of the regenerated allogenic cartilage. Importantly, TPU/GT-encapsulated cartilage-sheet constructs achieved stable allogeneic cartilage regeneration in a goat model. The current study provides a novel strategy for allogenic cartilage regeneration and supplies a new cartilage donor source to repair various cartilage defects.

Knockdown of long noncoding RNA MIAT attenuates hypoxia-induced cardiomyocyte injury by regulating the miR-488-3p/Wnt/β-catenin pathway

Dysfunction of cardiomyocytes contributes to the development of acute myocardial infarction (AMI). Nonetheless, the regulatory mechanism of lncRNA myocardial infarction-associated transcript (MIAT) in cardiomyocyte injury remains largely unclear. The cardiomyocyte injury was assessed via cell viability and apoptosis using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) and flow cytometry, respectively. The levels of MIAT, microRNA (miR)-488-3p, and Wnt5a were detected via quantitative real-time polymerase chain reaction and Western blot. After bioinformatical analysis, the binding between miR-488-3p and MIAT or Wnt5a was confirmed via dual-luciferase reporter, RNA immunoprecipitation, and RNA pull-down assays. Our results showed that MIAT expression was increased in AC16 cells after hypoxia treatment. Silencing of MIAT alleviated hypoxia-induced viability reduction, apoptosis increase, and Wnt/β-catenin pathway activation. MIAT directly targeted miR-488-3p. MiR-488-3p might repress hypoxia-induced cardiomyocyte injury, and its knockdown reversed the effect of MIAT depletion on cardiomyocyte injury. Wnt5a was validated as a target of miR-488-3p. Wnt5a expression restoration attenuated the influence of MIAT knockdown on hypoxia-triggered cardiomyocyte injury. Our findings demonstrated that downregulation of MIAT might mitigate hypoxia-induced cardiomyocyte injury partly through miR-488-3p mediated Wnt/β-catenin pathway.

Anti-apoptotic and anti-fibrotic efficacy of exercise training in hypertensive hearts: A systematic review

Background

This review aims to summarize the antiapoptotic, pro-survival, and antifibrotic effects of exercise training in hypertensive hearts.

Methods

Keyword searches were conducted in PubMed, Web of Science, and Scopus in May 2021. Research published in English on the effects of exercise training on the apoptosis, survival, and fibrosis pathways in hypertension was included. The CAMARADES checklist was used to determine the quality of the studies. Two reviewers independently implemented predesigned protocols for the search and selection of studies, the assessment of study quality, and the evaluation of the strength of evidence.

Results

Eleven studies were included after selection. The duration of the exercise training ranged from 5 to 27 weeks. Nine studies showed that exercise training improved cardiac survival rates by increasing IGF-1, IGF-1 receptor, p-PI3K, Bcl-2, HSP 72, and p-Akt. Furthermore, 10 studies showed that exercise training reduced apoptotic pathways by downregulating Bid, t-Bid, Bad, Bak, Bax, TNF, and FADD. Finally, two studies reported the modification and subsequent improvement of physiological characteristics of fibrosis and decreased MAPK p38 and PTEN levels by exercise training in the left ventricle of the heart.

Conclusions

The findings of the review showed that exercise training could improve cardiac survival rates and attenuate cardiac apoptotic and fibrotic pathways in hypertension, suggesting that exercise training could act as a therapeutic approach to prevent hypertension-induced cardiac apoptosis and fibrosis.

Systematic Review Registration

https://www.crd.york.ac.uk, identifier: CRD42021254118.

Orlistat Mitigates Oxidative Stress-Linked Myocardial Damage via NF-κβ- and Caspase-Dependent Activities in Obese Rats

Oxidative stress contributes to major complications of obesity. This study intended to identify whether orlistat could mitigate myocardial damage in obese animal models. The tested rats were divided into two groups and fed either with normal chow (n = 6 per group) or with a high-fat diet (HFD) for 6 weeks to induce obesity (n = 12 per group). Obese rats were further subjected to treatment either with distilled water (OB group) or orlistat 10 mg/kg/day (OB + OR group). Key indices of oxidative stress, inflammation, and apoptosis were assessed using an immunohistochemical-based technique and real-time PCR. The OB group showed significant increases of oxidative stress markers (TBARs and PCO), with significant decreases of anti-oxidant markers (Nrf2, SOD, CAT, and GPx). Furthermore, mRNA expression of pro-inflammatory markers (TNF-α and NF-κβ) and pro-apoptosis markers (Bax, Caspase-3, Caspase-8, and Caspase-9) were significantly upregulated in the OB group. Obese rats developed pathological changes of myocardial damages as evidenced by the presence of myocardial hypertrophy and inflammatory cells infiltration. Orlistat dampened the progression of myocardial damage in obese rats by ameliorating the oxidative stress, and by inhibiting NF-κβ pathway and caspase-dependent cell apoptosis. Our study proposed that orlistat could potentially mitigate oxidative stress-linked myocardial damage by mitigating inflammation and apoptosis, thus rationalizing its medical usage.

Angiotensin II Receptor Blocker Irbesartan Enhanced SIRT1 longevity Signaling Replaces the Mitochondrial Biogenetic Survival Pathway to Attenuate Hypertension-Induced Heart Apoptosis

Background: The present study investigated whether angiotensin II type 1 receptor blocker irbesartan (ARB) and partial agonist of PPAR-γ prevents heart apoptosis by suppressing cardiac Fas/FasL-mediated to mitochondria-mediated apoptosis in the hearts of hypertensive rat model. Methods: Cardiac function using echocardiography, H&E staining, TUNEL assay, and Western blotting were measured in the excised hearts from three groups, i.e., an untreated hypertensive group (SHR), an ARB-treated hypertensive group (50 mg/kg/day, S.C., SHR-ARB), and untreated normotensive Wistar-Kyoto rats (WKY). Results: Fas Ligand, Fas death receptors, FADD, active caspase-8, active caspase-3 (Fas/FasL-mediated apoptotic pathway), as well as Bax, cytochrome c, active caspase-9 and -3 (mitochondria-mediated apoptotic pathway), IGF-II, and p-JNK were decreased in SHR-ARB group when compared with the SHR group. SIRT1, PGC-1α, Bcl2, and Bcl-xL (SIRT1/PGC-1α pro-survival pathway) were increased in the SHR-ARB group when compared with the SHR group. Conclusions: Our findings suggested that the ARB might prevent cardiac Fas/FasL-mediated to mitochondria-mediated apoptosis pathway in the hypertensive model associated with IGF-II, p-JNK deactivation, and SIRT1/PGC-1α pro-survival pathway upregulation. ARB prevents hypertension-enhanced cardiac apoptosis via enhancing SIRT1 longevity signaling and enhances the mitochondrial biogenetic survival pathway.

Global distribution of treatment resistance gene markers for leishmaniasis

Background

Pentavalent antimonials (Sb(V)) such as meglumine antimoniate (Glucantime®) and sodium stibogluconate (Pentostam®) are used as first‐line treatments for leishmaniasis, either alone or in combination with second‐line drugs such as amphotericin B (Amp B), miltefosine (MIL), methotrexate (MTX), or cryotherapy. Therapeutic aspects of these drugs are now challenged because of clinical resistance worldwide.

Methods

We reviewedthe recent original studies were assessed by searching in electronic databases such as Scopus, Pubmed, Embase, and Web of Science.

Results

Studies on molecular biomarkers involved in drug resistance are essential for monitoring the disease. We reviewed genes and mechanisms of resistance to leishmaniasis, and the geographical distribution of these biomarkers in each country has also been thoroughly investigated.

Conclusion

Due to the emergence of resistant genes mainly in anthroponotic Leishmania species such as L. donovani and L. tropica, as the causative agents of ACL and AVL, respectively, selection of an appropriate treatment modality is essential. Physicians should be aware of the presence of such resistance for the selection of proper treatment modalities in endemic countries.

Anti-apoptotic effects of diosgenin on ovariectomized hearts

BACKGROUND

The anti-apoptotic effects of diosgenin, a steroid saponin, on hearts in female with estrogen deficiency have been less studied. This study aimed to evaluate the anti-apoptotic effects of diosgenin on cardiac widely dispersed apoptosis in a bilateral ovariectomized animal model.

METHODS

A total of 60 female Wistar rats, aged 6-7 months, were divided into the sham-operated group (Sham), bilateral ovariectomized rats for 2 months, and ovariectomized rats administered with 0, 10, 50, or 100 mg/kg diosgenin daily (OVX, OVX 10, OVX 50, and OVX 100, respectively) in the second month. The excised hearts were analyzed by H&E staining, TUNEL(+) assays and Western Blot.

RESULT

Cardiac TUNEL(+) apoptotic cells, the levels of Fas ligand, Fas death receptors, Fas-associated death domain, active caspase-8, and active caspase-3 (FasL/Fas-mediated pathways) as well as the levels of Bax, Bad, Bax/Bcl2, Bad/p-Bad, cytosolic Cytochrome c, active caspase-9, and active caspase-3 (mitochondria-initiated pathway) were increased in OVX compared with Sham group but those were decreased in OVX 50 compared with OVX.

CONCLUSION

Diosgenin appeared to prevent or suppress ovariectomy-induced cardiac FasL/Fas-mediated and mitochondria-initiated apoptosis. These findings might provide one of the possible therapeutic approaches of diosgenin for potentially preventing cardiac apoptosis in women after bilateral ovariectomy or women with estrogen deficiency.

Attenuated Cardiac oxidative stress, inflammation and apoptosis in Obese Mice with nonfatal infection of Escherichia coli

Obesity is a risk factor of many diseases, but could be beneficial to the individuals with bacterial infection. The present study was conducted to investigate the relationship between obesity and heart during nonfatal bacterial infection. Male normal (lean) and diet-induced obesity mice (DIO, fed with high-fat diet) were chosen to perform nasal instillation with E. coli to establish a nonfatal acute mouse model. The cardiac histopathology, inflammation and oxidative damage, as well as apoptosis were detected post-infection. The results revealed that the Escherichia coli (E.coli)-infected mice exhibited increased cardiac index, contents of IL-1β, IL-6, IL-8, TNF-α, leptin and resistin, levels of apoptotic proteins (caspase-3 and caspase-9, and bax/bcl-2 ratio), cardiac pathological changes and oxidative stress. Furthermore, these parameters were more serious in the lean mice than those in the DIO mice. In summary, our findings gave a new sight that E.coli infection impaired heart via histopathological lesions, inflammation and oxidative stress and excessive apoptosis of cardiomyocytes. Interestingly, obesity exerted attenuated effects on the heart of mice with non-fatal infection of E.coli through decreased inflammation, oxidative stress and apoptosis of cardiac tissue.

Caspofungin resistance in clinical Aspergillus Flavus isolates

INTRODUCTION AND AIMS

The present study was conducted to determine the candidate genes involved in caspofungin (CAS) resistance in clinical isolates of Aspergillus flavus (A. flavus).

MATERIALS AND METHODS

The antifungal susceptibility assay of the CAS was performed on 14 clinical isolates of A. flavus using the CLSI-M-38-A2 broth micro-dilution protocol. Since CAS had various potencies, the minimum effective concentration (MEC) of anidulafungin (AND) was also evaluated in the present study. The FKS1 gene sequencing was conducted to assess whether mutations occurred in the whole FKS1 gene as well as hot spot regions of the FKS1 gene of the two resistant isolates. A complementary DNA-amplified fragment length polymorphism (CDNA-AFLP) method was performed to investigate differential gene expression between the two resistant and two sensitive clinical isolates in the presence of CAS. Furthermore, quantitative real-time PCR (QRT-PCR) was utilized to determine the relative expression levels of the identified genes.

RESULTS

No mutations were observed in the whole FKS1 gene hot spot regions of the FKS1 genes in the resistant isolates. A subset of two genes with known biological functions and four genes with unknown biological functions were identified in the CAS-resistant isolates using the CDNA-AFLP. The QRT-PCR revealed the down-regulation of the P-type ATPase and ubiquinone biosynthesis methyltransferase COQ5 in the CAS-resistant isolates, compared to the susceptible isolates.

CONCLUSION

The findings showed that P-type ATPase and ubiquinone biosynthesis methyltransferase COQ5 might be involved in the CAS-resistance A. flavus clinical isolates. Moreover, a subset of genes was differentially expressed to enhance fungi survival in CAS exposure. Further studies are recommended to highlight the gene overexpression and knock-out experiments in A. flavus or surrogate organisms to confirm that these mentioned genes confer the CAS resistant A. flavus.

Real-time in situ monitoring of Lon and Caspase-3 for assessing the state of cardiomyocytes under hypoxic conditions via a novel Au-Se fluorescent nanoprobe

Myocardial dysfunction caused by cardiomyocyte apoptosis under ischemic and hypoxic conditions is the pathological basis of most cardiovascular diseases. Current diagnosis of myocardial dysfunction still focuses on the symptomatic stage, usually after the occurrence of the irreversible remodelling and functional impairment. Thus, early stage identification of the apoptotic cardiomyocytes induced by hypoxia is highly significant for preventing the onset and delaying the progression of myocardial dysfunction. Herein, a novel Au-Se nanoprobe with strong anti-interference capability was developed for simultaneous real-time in situ monitoring the expression of Lon protease (Lon) and Caspase-3 with high-fidelity in living cardiomyocytes. As Lon upregulation plays a major role in the initiation of hypoxia-induced apoptosis and Caspase-3 is a marker protein for apoptosis, the nanoprobe has been successfully applied for imaging the activation of Lon-Caspase-3 apoptotic signalling pathway and assessing the state of cardiomyocytes under hypoxic conditions. Furthermore, combining with mitochondrial H₂O₂ probe-MitoPY1, the nanoprobe was also used to confirm the synergistic effect of Lon and ROS on hypoxia-induced apoptosis of cardiomyocytes and evaluate the function of ROS scavenger on attenuating such apoptosis. This work proposed a promising strategy for early diagnosis, prevention and treatment of hypoxic-ischemic myocardial dysfunction.

Steroid use after cardiac arrest is associated with favourable outcomes: a systematic review and meta-analysis

Background

The effect of steroid use on outcomes in patients with cardiac arrest (CA) remains controversial. We systematically reviewed the literature to investigate whether steroid use after CA increased the return of spontaneous circulation (ROSC) rate and survival to discharge in patients with CA.

Methods

PubMed, Embase, CNKI, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) and observational studies on the effect of steroid use on outcomes in adults with CA. The outcomes were ROSC and survival to discharge.

Results

Seven studies (four RCTs and three observational studies) were included. Pooled analysis suggested that steroid use was associated with increased ROSC in patients with CA. Steroid use was significantly associated with survival to discharge, which was a consistent finding in RCTs and observational studies. Subgroup analysis based on the time of drug administration (during cardiopulmonary resuscitation [CPR] vs. after CA) showed that steroid use during CPR and after CA were significantly associated with an increased rate of ROSC and survival to discharge.

Conclusion

Current evidence indicates that steroid use after CA could increase ROSC and survival to discharge in patients with CA. However, high-quality and adequately powered RCTs are warranted.

Cardioprotective effect of Rosa canina L. methanolic extract on heat shock induced cardiomyocyte injury: An experimental study

Introduction: Overexposure to heat conditions can affect the functioning of the cardiovascular system and may promote cardiovascular disorders. Heat shock induced myocardial injury via increasing endoplasmic reticulum response-mediated apoptosis. This study investigated the impact of pretreatment with Rosa canina (RC), a natural antioxidant, on myocardial damage induced by heat stress exposure and underlying mechanisms in cardiomyocytes in rats. Methods: Sixty adult male Wistar rats were allocated into five groups, including Control: received normal saline (NS), Heat Stress (HS), and HS+RC groups. Animals in the HS groups were subjected to heat stress (43 ºC) for 15 minutes once a day for two weeks. Animals in the HS+RC groups received three doses of RC (250, 500, and 1000 mg/mL) one hour before being subjected to heat shock. The endoplasmic reticulum (ER) transmembrane kinases, including PKR-like endoplasmic reticulum kinase (PERK), immunoreactivity of CCAAT/enhancer-binding protein homologous protein (CHOP), and eukaryotic translation initiation factor 2-alpha (eIF2α) as well as caspase 8 were detected by Western blot. The levels of reactive oxygen species (ROS) were assessed. Moreover, histopathological changes and apoptosis were also assayed in the heart tissue by using histopathological and TUNEL assays. Results: Heat exposure increased the level of ROS and induced oxidative damage in the heart tissue. The results demonstrated that RC administration decreased the overproduction of ROS induced by heat stress in cardiomyocytes. Moreover, heat stress up regulated the expression of p-PERK, p-eIF2α,and CHOP protein while pretreatment with RC decreased expression of ER stress-related markers in cardiomyocytes. Besides, RC diminished heat stress-induced cellular damage and apoptosis associated with inhibition of caspase 8 activation, a pro-apoptotic protein in cardiomyocytes. Conclusion: These findings indicate that RC exerts a protective effect on heart tissue, at least in part,through inactivation of PERK/eIF2α/CHOP pathway or inhibition of ER stress and oxidative stress triggeredapoptosis in cardiomyocytes induced by heat stress.

Voluntary exercise training attenuated the middle-aged maturity-induced cardiac apoptosis

AIMS

Voluntary exercise training has cardioprotective effects in humans, but the underlying mechanism is unknown. This research was done to estimate the effect of voluntary exercise training to attenuate middle-aged maturity-induced cardiac apoptosis.

MATERIALS AND METHODS

The study was designed to divide 64 male mice randomly into four groups, consisting of a 9-month sedentary pre-middle-aged group (9M), 15-month sedentary middle-aged group (15M), and two exercise groups using a voluntary wheel running respectively (9M+EX, 15M+EX). After 3 months, the condition of cardiac apoptosis in different groups was measured by HE dying, TUNEL and DAPI staining, and Western Blot analysis.

KEY FINDINGS

TUNEL-positive cells were increased in 15M group compared with 9M group, while decreased in 9M+EX and 15M+EX groups compared with their control groups respectively. Protein levels of AIF, Endo G, TNF-α, TNFR1, TRAF2, TRADD, Fas, FasL, FADD, activated caspase 8, 3, 9, Bax/Bcl2, Bak/BclxL, and tBid were decreased in 9M+EX and 15M+EX groups compared with their control groups respectively. The protein levels of pBad/Bad, 14-3-3, IGF1, IGFR1, pPI3K/PI3K, and pAKT/AKT were more activated in the 9M+EX and 15M+EX groups than those in their control groups respectively. Significant differences were found between 9M group and 15M group for the protein levels of TRAF2, FADD, Bax/Bcl2, tBid and pAKT/AKT.

SIGNIFICANCE

Voluntary exercise training as an important lifestyle modification may prevent cardiac widely dispersed apoptosis and enhance cardiac survival at middle-aged maturity.

Cardioprotective Effect of (Z)-2-Acetoxy-3-(3,4-Dihydroxyphenyl) Acrylic Acid: Inhibition of Apoptosis in Cardiomyocytes

Background

Although many studies have been performed to elucidate the molecular mechanisms of heart failure, an effective pharmacological therapy to protect cardiac tissues from severe loss of contractile function associated with heart failure after acute myocardial infarction (MI) has yet to be developed.

Methods

We examined the cardioprotective effects of (Z)-2-acetoxy-3-(3,4-dihydroxyphenyl) acrylic acid, a new compound with potent antioxidant and antiapoptotic activities in a rat model of heart failure. (Z)-2-Acetoxy-3-(3,4-dihydroxyphenyl) acrylic acid was systemically delivered to rats 6 weeks after MI at different doses (15, 30, and 60 mg/kg). Cardiac function was assessed by hemodynamic measurements. The expression of proinflammatory cytokines, apoptosis-related molecules, and markers of adverse ventricular remodeling was measured using RT-PCR and Western blot.

Results

Treatment with (Z)-2-acetoxy-3-(3,4-dihydroxyphenyl) acrylic acid significantly improved cardiac function, in particular by increasing dP/dt. Simultaneously, the expression of the proinflammatory cytokines TNF-α and IL-1β was markedly reduced in the treatment group compared with the MI group. In addition, (Z)-2-acetoxy-3-(3,4-dihydroxyphenyl) acrylic acid-treated tissues displayed decreased expression of Bax, caspase-3, and caspase-9 and increased expression of Bcl-2, which was in part due to the promotion of Akt phosphorylation.

Conclusion

These data demonstrated that (Z)-2-acetoxy-3-(3,4-dihydroxyphenyl) acrylic acid possesses potent cardioprotective effects against cardiac injury in a rat model of heart failure, which is mediated, at least in part, by suppression of the inflammatory and cell apoptosis responses.

Pathogenesis and Prevention of Worsening Axial Elongation in Pathological Myopia

PURPOSE

This review discusses the etiology and pathogenesis of myopia, prevention of disease progression and worsening axial elongation, and emerging myopia treatment modalities.

INTRODUCTION

Pediatric myopia is a public health concern that impacts young children worldwide and is associated with numerous future ocular diseases such as cataract, glaucoma, retinal detachment and other chorioretinal abnormalities. While the exact mechanism of myopia of the human eye remains obscure, several studies have reported on the role of environmental and genetic factors in the disease development.

METHODS

A review of literature was conducted. PubMed and Medline were searched for combinations and derivatives of the keywords including, but not limited to, "pediatric myopia", "axial elongation", "scleral remodeling" or "atropine." The PubMed and Medline database search were performed for randomized control trials, systematic reviews and meta-analyses using the same keyword combinations.

RESULTS

Studies have reported that detection of genetic correlations and modification of environmental influences may have a significant impact in myopia progression, axial elongation and future myopic ocular complications. The conventional pharmacotherapy of pediatric myopia addresses the improvement in visual acuity and prevention of amblyopia but does not affect axial elongation or myopia progression. Several studies have published varying treatments, including optical, pharmacological and surgical management, which show great promise for a more precise control of myopia and preservation of ocular health.

DISCUSSION

Understanding the role of factors influencing the onset and progression of pediatric myopia will facilitate the development of successful treatments, reduction of disease burden, arrest of progression and improvement in future of the management of myopia.

Predictive role of ventricular repolarization parameters for the occurrence of complete heart block in patients undergoing transcatheter aortic valve implantation

Background

We investigated the role of ventricular repolarization parameters to predict complete atrioventricular block in patients undergoing transcatheter aortic valve implantation (TAVI).

Methods

A total of 150 patients undergoing TAVI due to severe aortic stenosis were included in this retrospective cohort study. Patients were assigned in two groups based on the presence (n: 49) or absence (n: 101) of complete atrioventricular block after TAVI. Ventricular repolarization intervals (QT, QTc, JT, JTc, TP‐E), indices (QT dispersion), and ratios (TP‐E/QT, TP‐E/QTc, TP‐E/JTc) were measured.

Results

Electrocardiographic repolarization parameters such as Tp‐e interval: 74.2 ± 5.1 versus 59.2 ± 6.1 ms, p < .001; QTc interval: 397.6 ± 3.4 versus 368.1 ± 7.8 ms, p < .001; JTc interval: 317.4 ± 11.3 versus 291.1 ± 6.7 ms, p < .001; Tp‐e/QT ratio: 0.28 ± 0.04 versus 0.20 ± 0.04, p < .001; Tp‐e/QTc ratio: 0.29 ± 0.04 versus 0.19 ± 0.03, p < .001; Tp‐e/JT ratio: 0.32 ± 0.03 versus 0.23 ± 0.03, p < .001; Tp‐e/JTc ratio: 0.30 ± 0.02 versus 0.2 ± 0.03, p < .001; and QT dispersion: 34.4 ± 3.0 versus 17.8 ± 3.6 ms, p < .01 were significantly higher in post‐TAVI permanent pacemaker group. In a univariate regression analysis, pulmonary artery pressure, heart rate, coronary artery disease, Tp‐e/QTc, Tp‐e/JTc, and PR interval were significantly associated with complete heart block. Tp‐e/JTc (OR 0.373, p = .067) and PR interval (OR 0.898, p = .079) were found to be independent predictors of these type of arrhythmias in a multivariate analysis. But it is not statistically significant.

Conclusion

Our results suggest that repolarization parameters may play a role in predicting complete atrioventricular block. Tp‐e/JTc was found to be potential independent risk marker for this setting.

Carthamus tinctorius L. extract activates insulin-like growth factor-I receptor signaling to inhibit FAS-death receptor pathway and suppress lipopolysaccharides-induced H9c2 cardiomyoblast cell apoptosis

Carthamus tinctorius L. (Compositae) is used in Chinese medicine to treat heart disease and inflammation. In our previous study, we found that C. tinctorius L. inhibited lipopolysaccharides (LPS)-induced tumor necrosis factor-alpha (TNF-α) activation, JNK expression, and apoptosis in H9c2 cardiomyoblast cells. The present study was performed to investigate the protective effect of C. tinctorius extract (CTF) on LPS-challenged H9c2 myocardioblast cell and to explore the possible underlying mechanism. Cell viability assay showed that LPS treatment decreased the cell viability of H9c2 cell, whereas CTF treatment reversed LPS cytotoxicity in a dose-dependent manner, especially in the LPS + CTF 25 (μg/mL) group. LPS treatment-induced apoptosis was determined by transferase-mediated dUTP nick end labeling assay, and by Western blot. LPS-induced apoptotic bodies were decreased following CTF treatment. Expression of TNF-α, FAS-L, FAS, FADD, caspase-8, BID, and t-BID was significantly increased in LPS-treated H9c2 cells. In contrast, it was significantly suppressed by the administration of CTF extract. In addition, CTF treatment activates antiapoptotic proteins, Bcl-2 and p-Bad, and downregulates Bax, cytochrome-c, caspase-9, caspase-3, and apoptosis-inducing factor expression. Furthermore, CTF exerted cytoprotective effects by activating insulin-like growth factor-I (IGF-I) signaling pathway leading to downregulation of the apoptotic proteins involved in FAS death receptor pathway. In addition, AG1024 and IGF-I receptor (IGF-IR) inhibitor and siRNA silencing reverses the effect of CTF implying that CTF functions through the IGF-IR pathway to inhibit LPS-induced H9c2 apoptosis. These results suggest that treatment with CTF extract prevented the LPS-induced apoptotic response through IGF-I pathway.

MiR-149 Aggravates Pyroptosis in Myocardial Ischemia-Reperfusion Damage via Silencing FoxO3

BACKGROUND MicroRNAs (miRNAs), which modulate the expression of their target genes, are commonly involved in stimulating and adjusting of many processes that result in cardiovascular diseases, contain cardiac ischemia/reperfusion (I/R) damage. However, the expression and role of miR-149 in pyroptosis mediated myocardial I/R damage remains unclear. MATERIAL AND METHODS Real-time polymerase chain reaction was performed to measure the miR-149 and FoxO3 expression in I/R stimulated H9C2 cells. The cell proliferation, pyroptosis-related inflammatory genes in I/R-treated H9C2 cells transfected miR-149 mimics or miR-149 inhibitor were both explored. We predicted and confirmed miR-149 targets by using bioinformatics analyses and luciferase reporter assay. In addition, the potential relationship between miR-149 and FoxO3 in pyroptosis from I/R treated H9C2 cells was analyzed. RESULTS Our results showed that miR-149 was upregulated, while FoxO3 was downregulated in I/R stimulated H9C2 cells. Over-expression of miR-149 inhibited cell viability and promote pyroptosis, however, down-expression of miR-149 had an opposite effect in I/R treated H9C2 cells. Furthermore, miR-149 could negatively regulate FoxO3 expression by binding 3'UTR, whereas silencing of FoxO3 attenuated the effect of miR-149-mimics on cell proliferation and pyroptosis in I/R treated H9C2 cells. CONCLUSIONS Our study found that miR-149 played a critical role in pyroptosis during cardiac I/R injury, and thus, might provide a novel therapeutic target.

Postarrest Steroid Use May Improve Outcomes of Cardiac Arrest Survivors

OBJECTIVES

To evaluate the ramifications of steroid use during postarrest care.

DESIGN

Retrospective observational population-based study enrolled patients during years 2004-2011 with 1-year follow-up.

SETTING

Taiwan National Health Insurance Research Database.

PATIENTS

Adult nontraumatic cardiac arrest patients in the emergency department, who survived to admission.

INTERVENTIONS

These patients were classified into the steroid and nonsteroid groups based on whether steroid was used or not during hospitalization. A propensity score was used to match patient underlying characteristics, steroid use prior to cardiac arrest, the vasopressors, and shockable rhythm during cardiopulmonary resuscitation, hospital level, and socioeconomic status.

MEASUREMENTS AND MAIN RESULTS

There were 5,445 patients in each group after propensity score matching. A total of 4,119 patients (75.65%) in the steroid group died during hospitalization, as compared with 4,403 patients (80.86%) in the nonsteroid group (adjusted hazard ratio, 0.74; 95% CI, 0.70-0.77; p < 0.0001). The mortality rate at 1 year was significantly lower in the steroid group than in the nonsteroid group (83.54% vs 87.77%; adjusted hazard ratio, 0.73; 95% CI, 0.70-0.76; p < 0.0001). Steroid use during hospitalization was associated with survival to discharge, regardless of age, gender, underlying diseases (diabetes mellitus, chronic obstructive pulmonary disease, asthma), shockable rhythm, and steroid use prior to cardiac arrest.

CONCLUSIONS

In this retrospective observational study, postarrest steroid use was associated with better survival to hospital discharge and 1-year survival.

Formononetin attenuates monocrotaline‑induced pulmonary arterial hypertension via inhibiting pulmonary vascular remodeling in rats

Pulmonary arterial hypertension (PAH) is a life‑threatening disease induced by the excessive proliferation and reduced apoptosis of pulmonary artery smooth muscle cells (PASMCs). Formononetin (FMN) is a natural isoflavone with numerous cardioprotective properties, which can inhibit the proliferation and induce the apoptosis of tumor cells; however, whether FMN has a therapeutic effect on PAH remains unclear. In the present study, PAH was induced in rats with monocrotaline (MCT, 60 mg/kg); rats were then administered FMN (10, 30 or 60 mg/kg/day). At the end of the experiment, hemodynamic changes, right ventricular hypertrophy and lung morphological characteristics were evaluated. α‑smooth muscle actin (α‑SMA), proliferating cell nuclear antigen (PCNA), and TUNEL were detected by immunohistochemical staining. The expression of PCNA, Bcl‑2‑associated X protein (Bax), Bcl‑2 and, cleaved caspase‑3, and activation of AKT and ERK were examined by western blot analysis. The results demonstrated that FMN significantly ameliorated the right ventricular systolic pressure, right ventricular hypertrophy, and pulmonary vascular remodeling induced by MCT. FMN also attenuated MCT‑induced increased expression of α‑SMA and PCNA. The ratio of Bax/Bcl‑2 and cleaved caspase‑3 expression increased in rat lung tissue in response to FMN treatment. Furthermore, reduced phosphorylation of AKT and ERK was also observed in FMN‑treated rats. Therefore, FMN may provide protection against MCT‑induced PAH by preventing pulmonary vascular remodeling, potentially by suppressing the PI3K/AKT and ERK pathways in rats.

Thymoquinone suppresses platelet-derived growth factor-BB-induced vascular smooth muscle cell proliferation, migration and neointimal formation

The excessive proliferation and migration of vascular smooth muscle cells (VSMCs) are mainly responsible for vascular occlusion diseases, such as pulmonary arterial hypertension and restenosis. Our previous study demonstrated thymoquinone (TQ) attenuated monocrotaline‐induced pulmonary arterial hypertension. The aim of the present study is to systematically examine inhibitory effects of TQ on platelet‐derived growth factor‐BB (PDGF‐BB)–induced proliferation and migration of VSMCs in vitro and neointimal formation in vivo and elucidate the potential mechanisms. Vascular smooth muscle cells were isolated from the aorta in rats. Cell viability and proliferation were measured in VSMCs using the MTT assay. Cell migration was detected by wound healing assay and Transwell assay. Alpha‐smooth muscle actin (α‐SMA) and Ki‐67‐positive cells were examined by immunofluorescence staining. Reactive oxygen species (ROS) generation and apoptosis were measured by flow cytometry and terminal deoxyribonucleotide transferase–mediated dUTP nick end labelling (TUNEL) staining, respectively. Molecules including the mitochondria‐dependent apoptosis factors, matrix metalloproteinase 2 (MMP2), matrix metalloproteinase 9 (MMP9), PTEN/AKT and mitogen‐activated protein kinases (MAPKs) were determined by Western blot. Neointimal formation was induced by ligation in male Sprague Dawley rats and evaluated by HE staining. Thymoquinone inhibited PDGF‐BB–induced VSMC proliferation and the increase in α‐SMA and Ki‐67‐positive cells. Thymoquinone also induced apoptosis via mitochondria‐dependent apoptosis pathway and p38MAPK. Thymoquinone blocked VSMC migration by inhibiting MMP2. Finally, TQ reversed neointimal formation induced by ligation in rats. Thus, TQ is a potential candidate for the prevention and treatment of occlusive vascular diseases.

Pheretima aspergillum extract attenuates high-KCl-induced mitochondrial injury and pro-fibrotic events in cardiomyoblast cells

Hyperkalemia is often associated with cardiac dysfunction. In this study an earthworm extract (dilong) was prepared from dried Pheretima aspergillum powder and its effect against high-KCl challenge was determined in H9c2 cardiomyoblast cells. H9c2 cells pre-treated with dilong (31.25, 62.5, 125, and 250 mg/mL) for 24 hours, where challenged with different doses of KCl treatment for 3 hours to determine the protective mechanisms of dilong against cardiac fibrosis. High-KCl administration induced mitochondrial injury and elevated the levels of pro-apoptotic proteins. The mediators of fibrosis such as ERK, uPA, SP1, and CTGF were also found to be upregulated in high-KCl condition. However, dilong treatment enhanced IGF1R/PI3k/Akt activation which is associated with cell survival. In addition, dilong also reversed high-KCl induced cardiac fibrosis related events in H9c2 cells and displayed a strong cardio-protective effect. Therefore, dilong is a potential agent to overcome cardiac events associated with high-KCl toxicity.

Antiapoptotic and mitochondrial biogenetic effects of exercise training on ovariectomized hypertensive rat hearts

This study was to investigate the effects of exercise training on antiapoptotic pathways and mitochondrial biogenesis in ovariectomized hypertensive rats. Histopathological analysis, TUNEL assay, and Western blotting were performed on the excised hearts from female spontaneously hypertensive rats (SHR), which were divided into a sham-operated sedentary hypertensive (SHR-S), a sedentary hypertensive ovariectomized (SHR-O), and hypertensive ovariectomized rats that underwent treadmill exercise training (SHR-OT; 60 min/day, 5 days/wk) for 8 wk, along with normotensive Wistar Kyoto rats (WKY). When compared with the WKY group, the SHR-S group exhibited decreased protein levels of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and mitochondrial OPA-1 (mitochondrial biogenesis) and decreased further in the SHR-O group. The protein levels of p-PI3K, p-Akt, Bcl-2, Bcl-xL (prosurvival pathways), and the protein levels of PGC-1α and mitochondrial OPA1 (mitochondrial biogenesis) were increased in the SHR-OT group, but estrogen receptor (ER)α and ERβ were not changed when compared with the SHR-O group. The protein levels of t-Bid, Bad, Bax, cytosolic cytochrome c, activated caspase 9, and activated caspase 3 (mitochondria-dependent apoptotic pathways), as well as Fas ligand, TNF-α, Fas receptors, Fas-associated death domain, activated caspase 8 (Fas receptor-dependent apoptotic pathways) were decreased in the SHR-OT group, when compared with the SHR-O group. Exercise training protection on the coexistence of hypertension and ovariectomy-induced cardiac mitochondria-dependent and Fas receptor-dependent apoptotic pathways by enhancing the Bcl2-related and mitochondrial biogenetic prosurvival pathways might provide a new therapeutic effect on cardiac protection in oophorectomized early postmenopausal hypertensive women. NEW & NOTEWORTHY Widely dispersed cardiac apoptosis was found in the coexistence of hypertension and ovariectomy. Exercise training on a treadmill could prevent ovariectomized hypertension-induced widely dispersed cardiac apoptosis via mitochondria-dependent apoptotic pathway (t-Bid, Bad, Bax, cytosolic cytochrome c, activated caspase 9, and activated caspase 3) and Fas receptor-dependent apoptotic pathway (Fas ligand, tumor necrosis factor-α, Fas receptors, Fas-associated death domain, activated caspase 8, and activated caspase 3) through enhancing the Bcl2-related (p-PI3K, p-Akt, Bcl-2, Bcl-xL) and mitochondrial biogenetic (PGC-1α and mitochondrial optic atrophy 1) prosurvival pathways.

ERK1/2 mediates the lipopolysaccharide-induced upregulation of FGF-2, uPA, MMP-2, MMP-9 and cellular migration in cardiac fibroblasts

Myocardial fibrosis is a critical event during septic shock. Upregulation in the fibrosis signaling cascade proteins such as fibroblast growth factor (FGF), urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA) and activation of matrix metalloproteinases (MMPs) are widely associated with the development of myocardial infarction, dilated cardiomyopathy, cardiac fibrosis and heart failure. However, evidences suggest that the common upstream mediators of fibrosis cascade play little role in cardiac fibrosis induced by LPS; further, it is unknown if LPS directly triggers the expressions and/or activity of FGF-2, uPA, tPA, MMP-2 and MMP-9 in cardiac fibroblasts. In the present study, we treated primary cultures of cardiac fibroblasts with LPS to explore whether LPS upregulates FGF-2, uPA, tPA, MMP-2, MMP-9 and enhance cellular migration. Further the precise molecular and cellular mechanisms behind these LPS induced responses were identified. Inhibition assays on MAPKs using U0126 (ERK1/2 inhibitor), SB203580 (p38 MAPK inhibitor), SP600125 (JNK1/2 inhibitor), CsA (calcineurin inhibitor) and QNZ (NFκB inhibitor) show that LPS-induced upregulation of FGF-2, uPA, MMP-2 and MMP-9 in cardiac fibroblasts was mediated through ERK1/2 signaling. Collectively, our results provide a link between LPS-induced cardiac dysfunction and ERK1/2 signaling pathway and thereby implies ERK1/2 as a possible target to regulate LPS induced upregulation of FGF-2, uPA, MMP-2, MMP-9 and cellular migration in cardiac fibroblasts.

Protective effect of Fisetin against angiotensin II-induced apoptosis by activation of IGF-IR-PI3K-Akt signaling in H9c2 cells and spontaneous hypertension rats

BACKGROUND

Fisetin, a polyphenolic compound, has drawn notable attention owing to its antioxidant, anti-inflammatory, anti-cancer and neuroprotective effects. However, the cardiac effects of fisetin are not clear yet.

HYPOTHESIS

The aim of the present study is to examine the cardioprotective effect of fisetin against Ang-II induced apoptosis in H9c2 cells and in spontaneous hypertensive rats (SHR).

METHODS/STUDY DESIGN

The in vitro protective effect of fisetin was evaluated after the cells were treated with fisetin (50 µM/ml/ 24  h) for 2  h prior or after Ang-II administration to induce apoptosis. For in vivo experiments, SHRs were orally administered with fisetin (10  mg/kg) twice a week for 6 weeks. Cellular apoptosis was analyzed by TUNEL staining assay and the modulation in the expression levels of proteins involved in apoptosis and cell survival were determined by western blotting.

RESULTS

Our results demonstrate the potent cardioprotective efficacy of fisetin against Ang-II induced apoptosis in H9c2 cells and in SHR models. Fisetin administration reduced the apoptotic nuclei considerably And reduced the expression of apoptotic proteins such as TNF- α, Fas L, FADD, Cleaved caspase-3 and Cleaved PARP and increased the cell survival and anti-apoptotic proteins like Bcl-2, Bcl-x_L, p-IGF1R, p-PI3K and p-AKT in both in vitro and in vivo models.

CONCLUSION

In conclusion, the results of the present study reveal that fisetin activates the IGF-IR-dependent p-PI3K/p-Akt survival signaling pathway and suppresses the caspase dependent apoptosis.

Botulinum Toxin Type A Attenuates Apoptosis in Human Dermal Microvascular Endothelial Cells Exposed to an In Vitro Model of Ischemia/Reperfusion Injury

BACKGROUND

Botulinum toxin type A (BTXA) has been reported to increase survival of critically ischemic skin flaps; however, the effect of BTXA in human dermal microvascular endothelial cells (HDMECs) remains to be investigated. This study aimed to investigate the protective effect of BTXA in HDMECs exposed to an in vitro model of ischemia/reperfusion injury.

METHODS

HDMECs were isolated from human upper eyelid tissue and were randomly divided into 3 groups: 1.

CONTROL GROUP

culture under normoxic conditions (95% air and 5% CO₂); 2. hypoxia/reoxygenation (H/R) group: culture in a hypoxic incubator (94% N₂ + 5% CO₂ + 5% O₂) for 8 hours, followed by culture in saturated aerobic culture medium for 24 hours; and 3. BTXA group: treatment with BTXA for 12 hours before exposure to hypoxic conditions. Flow cytometry was used to analyze the apoptosis of HDMECs, and western blotting was used to detect the expression of apoptosis-related proteins.

RESULTS

H/R leads to severe injury in HDMECs, as evidenced by an increase in the percentage of apoptosis and an increase in expression of apoptosis-related proteins (Bax, cleaved-caspase-3, and cytochrome C). Moreover, H/R results in a decrease in expression of anti-apoptotic protein (Bcl-2), which can be significantly attenuated with BTXA treatment.

CONCLUSION

BTXA protects against apoptosis in HDMECs exposed to an in vitro model of H/R-induced injury.

Possible involvement of Fas/FasL-dependent apoptotic pathway in α-bisabolol induced cardiotoxicity in zebrafish embryos

α-Bisabolol, an unsaturated monocyclic sesquiterpene alcohol, is a common ingredient in many pharmaceuticals and personal care products (PPCPs). Despite being widely used, little is known about its toxic effects on organisms and aquatic environment. In this study, we investigated the developmental toxicity of α-Bisabolol, especially its effects on the cardiac development using zebrafish embryos as a model. Embryos at 4 h post-fertilization (hpf) were exposed to 10, 30, 50, 70, 90, and 100 μM α-Bisabolol until 144 hpf. α-Bisabolol caused phenotypic defects and the most striking one is the heart malformation. Treatment of α-Bisabolol significantly increased the cardiac malformation rate, the SV-BA distance, as well as the pericardial edema area, and reduced heart rate in a concentration-dependent manner. Notably, considerable numbers of apoptotic cells were mainly observed in the heart region of zebrafish treated with α-Bisabolol. Further study on α-Bisabolol induced apoptosis in the zebrafsh heart suggested that an activation of Fas/FasL-dependent apoptotic pathway. Taken together, our study investigated the cardiotoxicity of α-Bisabolol on zebrafish embryonic development and its underlying molecular mechanism, shedding light on the full understanding of α-Bisabolol toxicity on living organisms and its environmental impact.

Ischemia postconditioning protects dermal microvascular endothelial cells of rabbit epigastric skin flaps against apoptosis via adenosine A2a receptors

BACKGROUND

It has been shown that endogenous adenosine-induced by ischemia postconditioning attenuates apoptosis in recent studies; however, they focus only on parenchymal cells. The detailed mechanism has not been clearly clarified in any research and the subtype of adenosine receptors involved remains unknown. In our study, dermal microvascular endothelial cells (DMECs) are used to explore the role of adenosine A_2a receptor in the anti-apoptotic effects of ischemic postconditioning.

MATERIAL AND METHODS

The epigastric skin flaps of rabbits were elevated. After 4 h of ischemia, the flaps were either abruptly reperfused or postconditioned by six cycles of brief reperfusion (15s) and re-ischemia (15s). Adenosine A2a receptor agonist (CGS-21680) and antagonist (ZM-241385) were used separately in other groups. The apoptosis-related proteins and adenosine A2a receptors were determined by immunohistochemical staining. Then apoptosis index was calculated by TUNEL.

RESULTS

Ischemia/reperfusion caused severe damages in DMECs of flaps as demonstrated by an increase in apoptosis index and an increase in expressions of apoptosis-related proteins, which can be significantly attenuated by IPC treatment or exposure to a selective adenosine A_2a receptor agonist (all p values <.05). Meanwhile, the anti-apoptosis effects of IPC can be blocked by a selective adenosine A_2a receptor antagonist. Statistical analysis revealed that the increase of apoptosis index closely correlated inversely with the relative increase of adenosine A_2a receptors (p < .0001).

CONCLUSIONS

Ischemia postconditioning protects DMECs of rabbit skin flap against apoptosis via activation of adenosine A_2a receptors.

Galanin and its N-terminal fragments reduce acute myocardial infarction in rats

Agonists and antagonists for galanin receptor subtypes GalR1-3 can be used as putative therapeutics targets for the treatment of various human diseases. However, effects of galanin and its N-terminal fragments on myocardial ischemia/reperfusion injury remain unclear. This study was designed to assess the ability of the full-length galanin (GWTLNSAGYLLGPHAIDNHRSFSDKHGLT-NH2, G1), the natural fragments WTLNSAGYLL-NH2 (G2) and WTLNSAGYLLGPHA (G3), and their modified analogs WTLNAAGYLL (G4) and WTLNSAGYLLGPβAH (G5) to limit acute myocardial infarction in rats in vivo. The peptides G2-5 were synthesized by the automatic solid phase method using Fmoc technology, purified by preparative HPLC and identified by 1H NMR spectroscopy and MALDI -TOF mass spectrometry. The peptides G1-5 were administered by i.v. bolus injection at the onset of reperfusion at doses of 0.25, 0.50, 1.0, 2.0 or 3.0 mg/kg. The optimal doses of the peptides G1-5 significantly reduced the infarction area and decreased the activity of CK-MB and LDH in blood plasma at the end of reperfusion compared with the control. Among the peptides studied, G5 showed high efficacy in reducing the infarct size and the activity of necrosis markers in blood plasma with no significant effect on hemodynamic parameters. The results suggest that a novel agonist for galanin receptors G5 may be a promising tool for the treatment of myocardial ischemia/reperfusion (I/R) injury. Further studies are warranted to explore the stability of this peptide in blood plasma and mechanisms that contribute to its cardioprotective effects.

Combined effects of 17β-estradiol and exercise training on cardiac apoptosis in ovariectomized rats

Background

The purpose of this study was to investigate the combined 17β-estradiol (E2) and exercise training on cardiac pro-survival and anti-apoptotic pathways in ovariectomized rats.

Methods

Fifty-six female Sprague–Dawley rats were divided into a sham-operated (Sham), a bilaterally ovariectomized (OVX), an OVX treated with E2 (OVX-E2; 10μg/kg/day), and an OVX with E2 and treadmill exercise training (OVX-E2-EX; 60 min/day, 5 days/week) for 10 weeks. Following 10 weeks of exercise training, rat hearts were isolated for the evaluation of Histopathological analysis, TUNEL assay, and Western blotting.

Results

The protein levels of estrogen receptor α (ERα), estrogen receptor β (ERβ), insulin-like growth factor 1 (IGF-1), IGF-1 receptor (IGF-1R), phospho-phosphatidylinositol 3-kinase (p-PI3K) (estrogen receptors/IGF-1-related survival pathway) were significantly increased in either the OVX-E2 or OVX-E2-EX group when compared with the OVX group. The protein levels of B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra-large (Bcl-xL) and phosphorylated-Bad (p-Bad) (Bcl-2 family survival pathway) were significantly increased in the OVX-E2-EX group when compared with the OVX group. Only the p-Bad was significantly increased in the OVX-E2 group when compared with the OVX group. The protein levels of truncation of Bid (t-Bid), Bcl-2-associated death promotor (Bad), Bcl-2-associated X protein (Bax), Cytochrome c, caspases-9, and caspases-3 (mitochondria-dependent apoptotic pathway), as well as the protein levels of tumor necrosis factor-α (TNF-α), Fas ligand, Fas receptors, Fas-associated death domain (FADD), activated caspase-8 and activated caspase-3 (Fas receptor–dependent apoptotic pathway) were significantly decreased in either the OVX-E2 or OVX-E2-EX group when compared with the OVX group. Furthermore, when compared with the OVX-E2 group, the protein levels of ERβ, IGF-1, IGF-1R, Bcl-2 and Bcl-xL were further enhanced in the OVX-E2-EX group as well as the protein levels of Cytochrome c, Fas receptors, FADD, activated caspase-8, activated caspase-9 and activated caspase-3 were further decreased in the OVX-EX-E2 group.

Conclusions

Combined E2 and exercise training exhibited a positive effect of protection on ovariectomy-induced cardiac apoptosis by enhancing ERβ-related survival pathways, which might provide a more effective therapeutic effect on cardiac protection in bilaterally oophorectomized or menopausal women than E2 treatment only.

Periostin alters transcriptional profile in a rat model of isoproterenol-induced cardiotoxicity

Periostin is an extracellular matrix protein from the fasciclin family that guides cellular trafficking and extracellular matrix organization. Periostin stimulates mature cardiomyocytes to reenter the cell cycle. The molecular mechanism behind such stimulation remains to be explored. A DNA microarray technology constituting 30,429 gene-level probe sets was utilized to investigate effects of recombinant murine periostin peptide on the gene expression pattern in a rat model of isoproterenol (ISO)-induced myocardial injury. The experiment was performed on 84 adult male Sprague-Dawley rats in four groups ( n = 21): (1) control group, (2) only periostin applied group, (3) ISO cardiotoxicity group, and (4) ISO + periostin group. The experiment was continued for 28 days, and rats were killed on days 1, 7, and 28 ( n = 7). Microarray analyses revealed that periostin significantly altered the expression of at least ±2-fold of 2474 genes in the ISO + periostin group compared to the ISO cardiotoxicity group of which 521 genes altered out of 30,429 gene-level probe sets. Ingenuity pathway analysis indicated that multiple pathway networks were affected by periostin, with predominant changes occurring in the expression of genes involved in oxidative phosphorylation, oxidative stress, fatty acid metabolism, and TNF-α NF-κB signaling pathways. These findings indicate that periostin alters gene expression profile in the ISO-induced myocardial injury and modulates local myocardial inflammation, possibly mitigating inflammation through TNF-α NF-κB signaling pathway along with a decreased Casp7 activity and apoptotic cell death.

Inhibition of JNK and p38 MAPK-mediated inflammation and apoptosis by ivabradine improves cardiac function in streptozotocin-induced diabetic cardiomyopathy

Inflammation plays a critical role in the development of diabetic cardiomyopathy (DCM), which has been identified as a major predisposing factor for heart failure in diabetic patients. Previous studies indicated that ivabradine (a specific agent for heart rate [HR] reduction) has anti-inflammatory properties, but its role in DCM remains unknown. This study investigated whether ivabradine exerts a therapeutic effect in DCM. C57BL/6J mice were injected intraperitoneally with streptozotocin (STZ) to induce diabetes; then administered with ivabradine or saline (control). After 12 weeks, the surviving mice were analyzed to determine the cardioprotective effect of ivabradine against DCM. Although treatment with ivabradine did not affect blood glucose levels, it attenuated tumor necrosis factor-α, interleukin-1β, and interleukin-6 messenger RNA (mRNA) expression, inhibited c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) activation, reduced histological abnormalities, myocardial apoptosis and collagen deposition, and improved cardiac function in the diabetic mice. Interestingly, the anti-inflammatory and antiapoptotic properties of ivabradine, but not its inhibitory effect on JNK and p38 MAPK, were observed in high-glucose-cultured neonatal rat ventricular cardiomyocytes. Attenuating inflammation and apoptosis via intramyocardial injection of lentiviruses carrying short hairpin RNA targeting JNK and p38 MAPK validated that the anti-inflammatory and antiapoptotic effects of ivabradine were partly attributed to JNK and p38 MAPK inactivation in diabetic mice. In summary, these data indicate that ivabradine-mediated improvement of cardiac function in STZ-induced diabetic mice may be partly attributed to inhibition of JNK/p38 MAPK-mediated inflammation and apoptosis, which is dependent on the reduction in HR.

Effect of cytokine-induced killer cells combined with dendritic cells on the survival rate and expression of 14-3-3ζ and p-Bad proteins in Lewis lung cancer cell lines

In the present study, the function and mechanism of cytokine-induced killer cells (CIK) combined with dendritic cells (DC-CIK) were examined in Lewis lung cancer (LLC) cells. Co-culture of CIK dendritic cells (DC) in vitro was used to investigate their proliferation and the antitumor effects on LLC cells. DC and CIK cells were collected from healthy human peripheral blood mononuclear cells and co-cultured as an experimental group, while LLC cells were cultured alone as a control group. Cell morphology was observed by an inverted microscope and an MTT assay was utilized to detect the proliferation of LLC cells. Expression of 14-3-3ζ and p-Bad were measured by western blot analysis. Compared with the control group, treatment of LLC cells with DC-CIK resulted in decreased cell adherence, reduced cell proliferation and abnormal morphological changes. Additionally, DC-CIK treatment of LLC cells resulted in the decreased expression of 14-3-3ζ and p-Bad protein in LLC cells, which may provide important information pertaining to the possible mechanism of DC-CIK-induced antitumor activity against LLC cells. The present study provides a theoretical and experimental basis for the clinical treatment of DC-CIK cell co-culture.

Cardiometabolic Changes in Different Gonadal Female States Caused by Mild Hyperuricemia and Exposure to a High-Fructose Diet

BACKGROUND

The objective of this study is to observe if mild hyperuricemia and a high-fructose diet influence the cardiovascular and metabolic systems in hypogonadic female Wistar rats compared to normogonadic female rats.

METHODS

Fifty-six (56) adult female Wistar rats were used in the present work. Animals were divided into two groups: normogonadic (NGN) and hypogonadic (HGN). These groups were also divided into four subgroups in accordance with the treatment: control with only water (C), fructose (F), oxonic acid (OA), and fructose + oxonic acid (FOA). Lipid profile, glycemia, uric acid, and creatinine determinations were assessed. Cardiovascular changes were evaluated by measuring blood pressure, myocyte volume, fibrosis, and intima-media aortic thickness.

RESULTS

HGN rats had higher levels of total cholesterol (TC) (p < 0.01) and noHDLc (p < 0.01), in addition to higher levels of uric acid (p < 0.05). The OA group significantly increased myocyte volume (p < 0.0001) and the percentage of fibrosis as well as the group receiving FOA (p < 0.001) in both gonadal conditions, being greater in the HGN group. Hypogonadic animals presented a worse lipid profile.

CONCLUSION

Mild hyperuricemia produces hypertension together with changes in the cardiac hypertrophy, fibrosis, and increased thickness of the intima media in hypogonadic rats fed high-fructose diet.

Capsaicin Protects Cardiomyocytes against Anoxia/Reoxygenation Injury via Preventing Mitochondrial Dysfunction Mediated by SIRT1

Capsaicin (Cap) has been reported to have beneficial effects on cardiovascular system, but the mechanisms underlying these effects are still poorly understood. Apoptosis has been shown to be involved in mitochondrial dysfunction, and upregulating expression of SIRT1 can inhibit the apoptosis of cardiomyocytes induced by anoxia/reoxygenation (A/R). Therefore, the aim of this study was to test whether the protective effects of Cap against the injury to the cardiomyocytes are mediated by SIRT1. The effects of Cap with or without coadministration of sirtinol, a SIRT1 inhibitor, on changes induced by A/R in the cell viability, activities of lactate dehydrogenase (LDH), creatine phosphokinase (CPK), levels of intracellular reactive oxygen species (ROS), and mitochondrial membrane potential (MMP), related protein expression, mitochondrial permeability transition pore (mPTP) opening, and apoptosis rate in the primary neonatal rat cardiomyocytes were tested. Cap significantly increased the cell viability, upregulated expression of SIRT1 and Bcl-2, and decreased the LDH and CPK release, generation of ROS, loss of MMP, mPTP openness, activities of caspase-3, release of the cytochrome c, and apoptosis of the cardiomyocytes. Sirtinol significantly blocked the cardioprotective effects of Cap. The results suggest that the protective effects of Cap against A/R-induced injury to the cardiomyocytes are involved with SIRT1.

Attenuation of the hypoxia-induced miR-34a protects cardiomyocytes through maintenance of glucose metabolism

Ischemic injury in the heart is associated with death of cardiomyocytes and even after decades of research there is no appropriate therapeutic intervention to treat ischemic injury. The microRNA miR-34a is known to be induced in cardiomyocytes following ischemic injury. Another hallmark of ischemic injury is impaired glycolysis. The objective of the current study was to investigate the effects of short- and long-term exposure to hypoxia on miR-34a expression on apoptosis and regulation of key glycolysis metabolic enzymes. Both repeated short-term (30 min) burst of hypoxia with intermittent reoxygenation (30 min) as well as long-term (4 h) exposure to hypoxia followed by 6 h of reoxygenation robustly induced miR-34a levels. Hypoxia induced changes in cardiac permeability and localization of the channel protein connexin 34 as well as induced apoptosis as evident by levels of cleaved-caspase 3/7 and impaired cell proliferation. Hypoxia was also associated with decreased expression of key glycolytic enzymes hexokinase-1, hexokinase-2, glucose-6-phosphate-isomerase, and pyruvate dehydrogenase kinase 1. Attenuation of hypoxia-induced miR-34a by anti-miR-34a antagomir, but not a control antagomir, decreased miR-34a levels to those observed under normoxia and also inhibited apoptosis, potentially by rescuing expression of the key glycolytic enzymes. Cumulatively, our results establish that therapeutic targeting of miR-34a via antagomir might be a potent therapeutic mechanism to treat ischemic injury in the heart.

Myocardial apoptosis and mesenchymal stem cells with acute exercise

Aerobic exercise confers many health benefits. However, numerous reports have shown that acute aerobic exercise can injure the heart. We tested the general hypothesis that acute moderate‐intensity exercise in rodents induces cardiomyocyte damage and stimulates mesenchymal stem cells (MSCs) to increase paracrine‐mediated protective effects on cardiomyocytes. A single session of treadmill running (13 m/min, 0% grade, for 45 min) in untrained C57BL/6 male mice (n = 18) increased cleaved poly ADP‐ribose polymerase (PARP), a marker of apoptosis, in the myocardium 24 h postexercise. Microarray analysis of mouse myocardium identified 11 relevant apoptotic genes and several shifts in matrix remodeling transcripts over the postexercise window. Postexercise cardiomyocyte death was recapitulated in neonatal rat cardiomyocytes (NRCMs) by culturing cells in 2% plasma harvested from exercised rats. The increased cell death observed in exercise‐treated NRCMs was attenuated by β‐adrenergic blockade, but not antioxidant treatment. MSC survival, proliferation, and chemotaxis showed no significant differences between sedentary and exercise plasma conditions, despite increased IL‐6, TNF‐α, IL‐1β, and IFN‐γ secretions from MSCs treated with exercise plasma. NRCM survival was increased nearly 500% when cocultured with MSCs, but this effect was not altered under exercise plasma culture conditions. Our results suggest acute moderate‐intensity aerobic treadmill running in exercise‐naïve rodents induces temporal cardiomyocyte death due to plasma‐borne factors, namely, catecholaminergic stress. Even though exercise conditions prompt an inflammatory response in MSCs, the exercise milieu does not alter the MSC‐protective phenotype on cardiomyocytes.

Suppression of phosphorylated MAPK and caspase 3 by carbon dioxide

Although CO₂ is produced during the oxidation of different substrates in all types of cells, the role of this gas in the regulation of cellular function is not clearly understood. Since changes in several signal transduction as well as apoptotic, anti-apoptotic, and other proteins are known to modify cellular function, we investigated if some of these proteins are altered upon incubating the rat hind leg skeletal muscle in a medium enriched with CO₂ (1000-1200 ppm) for 30 min. CO₂ was observed to depress phosphorylated levels of ERK1 (P44) and ERK2 (P42) without affecting the unphosphorylated content of these MAPK proteins. On the other hand, no change in p38 MAPK protein was found but the content of its degradation product 30 kDa proteins (both phosphorylated and unphosphorylated) was decreased. No alterations in the content of other signaling proteins (PKA and Akt), inflammatory molecule (TNF-α), and vascular endothelial growth factor (VEGF) were seen upon exposure of the muscle to CO₂. The content for apoptotic and anti-apoptotic proteins (Bad and Bcl2), except for a decrease in caspase 3, were also not affected by CO₂. These results indicate that CO₂ may serve as a gasotransmitter to regulate cellular function by depressing MAPK and caspase 3 activities.

Ciclosporin to Protect Renal function In Cardiac Surgery (CiPRICS): a study protocol for a double-blind, randomised, placebo-controlled, proof-of-concept study

INTRODUCTION

Acute kidney injury (AKI) after cardiac surgery is common and results in increased morbidity and mortality. One possible mechanism for AKI is ischaemia-reperfusion injury caused by the extracorporeal circulation (ECC), resulting in an opening of the mitochondrial permeability transition pore (mPTP) in the kidneys, which can lead to cell injury or cell death. Ciclosporin may block the opening of mPTP if administered before the ischaemia-reperfusion injury. We hypothesised that ciclosporin given before the start of ECC in cardiac surgery can decrease the degree of AKI.

METHODS AND ANALYSIS

Ciclosporin to Protect Renal function In Cardiac Surgery (CiPRICS) study is an investigator-initiated double-blind, randomised, placebo-controlled, parallel design, single-centre study performed at a tertiary university hospital. The primary objective is to assess the safety and efficacy of ciclosporin to limit the degree of AKI in patients undergoing coronary artery bypass grafting surgery. We aim to evaluate 150 patients with a preoperative estimated glomerular filtration rate of 15-90 mL/min/1.73 m². Study patients are randomised in a 1:1 ratio to receive study drug 2.5 mg/kg ciclosporin or placebo as an intravenous injection after anaesthesia induction but before start of surgery. The primary end point consists of relative P-cystatin C changes from the preoperative day to postoperative day 3. The primary variable will be tested using an analysis of covariance method. Secondary end points include evaluation of P-creatinine and biomarkers of kidney, heart and brain injury.

ETHICS AND DISSEMINATION

The trial is conducted in compliance with the current version of the Declaration of Helsinki and the International Council for Harmonisation (ICH) Good Clinical Practice guidelines E6 (R1) and was approved by the Regional Ethical Review Board, Lund and the Swedish Medical Products Agency (MPA). Written and oral informed consent is obtained before enrolment into the study.

TRIAL REGISTRATION NUMBER

NCT02397213; Pre-results.

Cardiac Fas-Dependent and Mitochondria-Dependent Apoptotic Pathways in a Transgenic Mouse Model of Huntington's Disease

Huntington's disease is an autosomal dominant neurodegenerative disease caused by a CAG repeat expansion in the huntingtin gene. Heart disease is the second leading cause of death in patients with Huntington's disease. This study was to evaluate whether cardiac Fas-dependent and mitochondria-dependent apoptotic pathways are activated in transgenic mice with Huntington's disease. Sixteen Huntington's disease transgenic mice (HD) and sixteen wild-type (WT) littermates were studied at 10.5 weeks of age. The cardiac characteristics, myocardial architecture, and two major apoptotic pathways in the excised left ventricle from mice were measured by histopathological analysis, Western blotting, and TUNEL assays. The whole heart weight and the left ventricular weight decreased significantly in the HD group, as compared to the WT group. Abnormal myocardial architecture, enlarged interstitial spaces, and more cardiac TUNEL-positive cells were observed in the HD group. The key components of Fas-dependent apoptosis (TNF-alpha, TNFR1, Fas ligand, Fas death receptors, FADD, activated caspase-8, and activated caspase-3) and the key components of mitochondria-dependent apoptosis (Bax, Bax-to-Bcl-2 ratio, cytosolic cytochrome c, activated caspase-9, and activated caspase-3) increased significantly in the hearts of the HD group. Cardiac Fas-dependent and mitochondria-dependent apoptotic pathways were activated in transgenic mice with Huntington's disease, which might provide one of possible mechanisms to explain why patients with Huntington's disease will develop heart failure.

The Coexistence of Hypertension and Ovariectomy Additively Increases Cardiac Apoptosis

To investigate whether the coexistence of hypertension and ovariectomy will increase cardiac Fas receptor and mitochondrial-dependent apoptotic pathways, histopathological analysis, the TUNEL assay and Western blotting were performed on the excised hearts from three groups of female spontaneously hypertensive rats (SHR), which were divided into a sham-operated group (SHR-Sham), bilaterally ovariectomized group (SHR-OVX) and normotensive Wistar Kyoto rats (WKY). Compared with the WKY group, the SHR-Sham group exhibited decreased protein levels of ERα, ERβ, p-Akt/Akt, Bcl-2, Bcl-xL and p-Bad and decreased further in the SHR-OVX group, as well as protein levels of t-Bid, Bak, Bad, Bax, cytochrome c, activated caspase-9 and activated caspase-3 (mitochondria-dependent apoptosis) increased in the SHR-Sham group and increased further in the SHR-OVX group. Compared with the WKY group, protein levels of Fas ligand, TNF-α, Fas death receptors, TNFR1, FADD and activated caspase-8 (Fas receptor-dependent apoptosis) increased in the SHR-Sham group, but did not increase in the SHR-OVX group, except Fas ligand and TNF-α. The coexistence of hypertension and ovariectomy attenuated the estrogen receptor survival pathway and appeared to additively increase the cardiac mitochondria-dependent, but not the Fas receptor-dependent apoptosis pathway, which might provide one possible mechanism for the development of cardiac abnormalities in hypertensive postmenopausal women.

ZAKβ antagonizes and ameliorates the cardiac hypertrophic and apoptotic effects induced by ZAKα

ZAK (sterile alpha motif and leucine zipper containing kinase AZK), a serine/threonine kinase with multiple biochemical functions, has been associated with various cell processes, including cell proliferation, cell differentiation, and cardiac hypertrophy. In our previous reports, we found that the activation of ZAKα signaling was critical for cardiac hypertrophy. In this study, we show that the expression of ZAKα activated apoptosis through both a FAS-dependent pathway and a mitochondria-dependent pathway by subsequently inducing caspase-3. ZAKβ, an isoform of ZAKα, is dramatically expressed during cardiac hypertrophy and apoptosis. The interaction between ZAKα and ZAKβ was demonstrated here using immunoprecipitation. The results show that ZAKβ has the ability to diminish the expression level of ZAKα. These findings reveal an inherent regulatory role of ZAKβ to antagonize ZAKα and to subsequently downregulate the cardiac hypertrophy and apoptosis induced by ZAKα.

Andrographis paniculata extract attenuates pathological cardiac hypertrophy and apoptosis in high-fat diet fed mice

ETHNOPHARMACOLOGICAL RELEVANCE

Andrographis paniculata (Burm. f.) Nees (Acanthaceae) has a considerable medicinal reputation in most parts of Asia as a potent medicine in the treatment of Endocrine disorders, inflammation and hypertension.

AIM OF THE STUDY

Water extract of A. paniculata and its active constituent andrographolide are known to possess anti-inflammatory and anti-apoptotic effects. Our aim is to identify whether A. paniculata extract could protect myocardial damage in high-fat diet induced obese mice.

MATERIALS AND METHODS

The test mice were divided into three groups fed either with normal chow or with high fat diet (obese) or with high fat diet treated with A. paniculata extract (2g/kg/day, through gavage, for a week).

RESULTS

We found that the myocardial inflammation pathway related proteins were increased in the obese mouse which potentially contributes to cardiac hypertrophy and myocardial apoptosis. But feeding with A. paniculata extract showed significant inhibition on the effects of high fat diet.

CONCLUSION

Our study strongly suggests that supplementation of A. paniculata extract can be used for prevention and treatment of cardiovascular disease in obese patients.