Sepsis-induced Cardiomyopathy Research Articles

Photoactivated adenylyl cyclases attenuate sepsis-induced cardiomyopathy by suppressing macrophage-mediated inflammation.

Sepsis-induced myocardiopathy, characterized by innate immune cells infiltration and proinflammatory cytokines release, may lead to perfusion failure or even life-threatening cardiogenic shock. Macrophages-mediated inflammation has been shown to contribute to sepsis-induced myocardiopathy. In the current study, we introduced two photoactivated adenylyl cyclases (PACs), Beggiatoa sp. PAC (bPAC) and Beggiatoa sp. IS2 PAC (biPAC) into macrophages by transfection to detect the effects of light-induced regulation of macrophage pro-inflammatory response and LPS-induced sepsis-induced myocardiopathy. By this method, we uncovered that blue light-induced bPAC or biPAC activation considerably inhibited the production of pro-inflammatory cytokines IL-1 and TNF-α, both at mRNA and protein levels. Further, we assembled a GelMA-Macrophages-LED system, which consists of GelMA-a type of light crosslink hydrogel, gene modulated macrophages and wireless LED device, to allow light to regulate cardiac inflammation in situ with murine models of LPS-induced sepsis. Our results showed significant inhibition of leukocytes infiltration, especially macrophages and neutrophils, suppression of pro-inflammatory cytokines release, and alleviation of sepsis-induced cardiac dysfunction. Thus, our study may represent an emerging means to treat sepsis-induced myocardiopathy and other cardiovascular diseases by photo-activated regulating macrophage function.

UTI-Associated Septic Cardiomyopathy: Saving the Heart in the Nick of Time

A patient with gram-negative sepsis developed acute global biventricular dysfunction with reduced left ventricular ejection fraction. A diagnosis of sepsis-induced cardiomyopathy (SICM) was made following the complete resolution of cardiac dysfunction. This case highlights the importance of the early diagnosis of SICM and treatment of the underlying cause.

Macrophage-Derived Exosomes in TLR9-/- Mice Ameliorate Sepsis-Induced Mitochondrial Oxidative Stress and Apoptosis in Cardiomyocytes.

Objective To explore the mechanisms of TLR9 from macrophages on mitochondrial apoptosis in cardiomyocytes at early stage of sepsis. Methods The in vivo and in vitro sepsis mice were bone marrow transplantation (BMT) with wild type (WT) or (toll-like receptor 9) TLR9 knockout (−/− or KO) myeloid cells and then constructed by cecum ligation and puncture (CLP) as vivo experiment and cardiomyocytes cocultured with WT or TLR9-deficient macrophages treated with LPS as vitro experiment, respectively. Sepsis model were performed by CLP. The expression levels of exosome, PI3K/AKT, and ERK1/2, inflammatory factors, and apoptotic proteins were tested by western blot in vivo. Besides, associated apoptotic proteins and JC-1 fluorescence assay were tested in vitro. Results The expressions of p-PI3K, p-AKT, exosome markers (CD9, CD63, and TSG101), p-ERK1/2, TNF-α, IFN-γ, IL-1β, and cleaved-caspase-3/-9 were significantly increased in septic mice vs. control mice, and these proteins were declined dramatically in TLR9−/− BMT mice vs. WT BMT mice in sepsis mice models. Meanwhile, the protein expression of cytochrome C, cleaved-caspase-3, and cleaved-caspase-9 increased significantly in primary mouse myocardial cells cocultured with TLR9−/− or WT macrophages stimulated with LPS, and these mitochondrial apoptotic proteins as well as the green 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolcarbocyanine iodide (JC-1) fluorescence were dramatically lower in LPS-stimulated cardiomyocytes cocultured with TLR9−/− than with WT macrophages. Conclusion TLR9−/− in macrophages suppressed the inflammatory reaction as well as the exosome secretion and resulted in the inhibition of apoptosis and oxidative stress in sepsis-induced cardiomyopathy.

Sepsis-Induced Cardiomyopathy Detected With Focused Cardiac Ultrasound in the Emergency Department

BackgroundSepsis is a high mortality condition characterized by multi-organ dysfunction. Sepsis-induced cardiomyopathy (SIC) refers to cardiac dysfunction in sepsis. ObjectivesOur goal was to determine whether SIC can be detected in the emergency department (ED) using focused cardiac ultrasound (FCU). MethodsA retrospective analysis of adults presenting to a single ED with sepsis over a 21-month period was performed. Patients were included if they met clinical sepsis criteria, received an FCU by an emergency physician in the ED, and a baseline echocardiogram performed in the previous 12 months. SIC was defined as a significant decrease in estimated left ventricular ejection fraction (LVEF) by FCU relative to baseline. Demographic and outcome characteristics were compared between three cohorts: patients with normal baseline LVEF and no decrease on presentation, patients with decreased LVEF and no significant change, and those with a significant decrease in LVEF from their normal baseline (SIC). ResultsThere were 110 patients that met inclusion criteria: 89 patients (81%) in the normal LVEF group, 12 (11%) in the prior decreased LVEF group, and 9 (8%) in the SIC group. Unadjusted mortality at 90 days for patients with SIC (67%) and prior decreased LVEF (58%) was significantly higher than those with normal EF (29%) (p = 0.019). When adjusted for age, gender, Charlson Index score, and lactate > 4.0 mmol/L, SIC was associated with mortality at 90 days (odds ratio 6.1, 95% confidence interval 1.37–32.92). ConclusionSIC can be detected using FCU by emergency physicians in the ED and is associated with increased 90-day mortality.

The search for novel biomarkers in sepsis-induced cardiomyopathy – A new challenge to overcome

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection and it remains the most frequent cause of death amongst critically ill patients worldwide, despite recent medical advancements. The cardiac involvement in sepsis, better known as sepsis-induced cardiomyopathy, represents a form of cardiac dysfunction identified in septic patients, characterized by ventricular dilation, myocardial involvement, decreased ejection fraction and reversibility. Although the implications of cardiac involvement in sepsis can be extremely severe, this affliction has not been intensely debated in literature. Therefore, in order to better understand this affliction, we need to identify new markers. Two biomarkers, endothelin-1 (ET-1) and the soluble form of suppression of tumorigenicity 2 protein (sST2) have previously been linked to both sepsis and acute/chronic heart failure. Endothelin-1 is part of a family of amino acid peptides, that is mainly produced by endothelial cells and exerts a vasoconstrictive effect, but also causes fibrosis of the vascular cells, stimulates production of reactive oxygen species and induces proinflammatory mechanisms. During sepsis, it induces coronary vasoconstriction, decreased cardiac output, increased vascular resistance and permeability and increased fluid flux into the extravascular space on cardiac level, as well as affecting the contractility of myocardial myocytes. High values of serum ET-1 have also been identified in septic shock and in endotoxin-induced febrile responses in rats. The Suppression of tumorigenicity 2 protein (ST2) is a member of the interleukin-1 receptor family and is involved in T helper 2 cells-associated immune response. Recent studies identified a close link between ST2 and both inflammatory and heart diseases. Furthermore, it was recently approved by the Food and Drug Administration as a prognostic biomarker in heart failure and is recommended for the evaluation of additional cardiovascular risk.

Losartan attenuates sepsis-induced cardiomyopathy by regulating macrophage polarization via TLR4-mediated NF-κB and MAPK signaling

Sepsis-induced cardiomyopathy (SIC) is a serious complication of sepsis with high mortality but no effective treatment. The renin angiotensin (Ang) aldosterone system (RAAS) is activated in patients with sepsis but it is unclear how the Ang II/Ang II type 1 receptor (AT1R) axis contributes to SIC. This study examined the link between the Ang II/AT1R axis and SIC as well as the protective effect of AT1R blockers (ARBs). The Ang II level in peripheral plasma and AT1R expression on monocytes were significantly higher in patients with SIC compared with those in non-SIC patients and healthy controls and were correlated with the degree of myocardial injury. The ARB losartan reduced the infiltration of neutrophils, monocytes, and macrophages into the heart and spleen of SIC mice. Additionally, losartan regulated macrophage polarization from the M1 to the M2 subtype via nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, thereby maintaining the mitochondrial dynamics balance in cardiomyocytes and reducing oxidative stress and cardiomyocyte apoptosis. In conclusion, the plasma Ang II level and AT1R expression on plasma monocytes are an important biomarker in SIC. Therapeutic targeting of AT1R, for example with losartan, can potentially protect against myocardial injury in SIC.

H2S regulation of ferroptosis attenuates sepsis‑induced cardiomyopathy.

Ferroptosis is a non-apoptotic form of cell death mediated by reactive oxygen species (ROS). Iron metabolism disorders play a key role in sepsis-induced cardiomyopathy (SIC). While hydrogen sulfide (H2S) inhibits SIC, it is unknown if it does so by controlling ferroptosis. The present study evaluated whether sodium hydrosulfide (NaHS), an H2S donor, alleviates SIC by decreasing ferroptosis. Lipopolysaccharide (LPS) was employed to induce an in vitro model of septic myocardial injury in rat H9c2 cardiomyocytes. The myocardial injury model of septic rats was established by cecal ligation and puncture (CLP). Cardiomyocyte injury was evaluated using Cell Counting Kit-8 and myocardial enzyme assay and hematoxylin and eosin (H&E) staining. The cardiac function of rats was assessed using echocardiography and changes in myocardial fibers and mitochondria were evaluated using H&E staining and transmission electron microscopy, respectively. Fe2+, glutathione and malondialdehyde levels in cardiomyocytes were detected using assay kits, ROS and mitochondrial membrane potential changes were detected using fluorescent probes and ferroptosis and Beclin 1 (BECN1) signaling pathway-associated protein expression levels were semi-quantified using western blotting. NaHS decreased ferroptosis of H9c2 cells induced by LPS and decreased injury of myocardial cells by improving iron metabolism disorder and oxidative stress levels. Furthermore, in vivo results demonstrated that NaHS attenuated CLP-induced septic myocardial ferroptosis and significantly improved cardiac dysfunction in septic rats compared with the CLP group. NaHS was demonstrated to attenuate sepsis-induced myocardial cell and tissue injury by significantly inhibiting the phosphorylation of BECN1 and significantly increasing expression levels of the ferroptosis regulatory proteins solute carrier family 7 member 11 and glutathione peroxidase 4. The results of the present study suggested that by regulating the BECN1 signaling pathway, NaHS may decrease the incidence of myocardial ferroptosis, thereby improving SIC.

Septic Cardiomyopathy: From Pathophysiology to the Clinical Setting.

The onset of cardiomyopathy is a common feature in sepsis, with relevant effects on its pathophysiology and clinical care. Septic cardiomyopathy is characterized by reduced left ventricular (LV) contractility eventually associated with LV dilatation with or without right ventricle failure. Unfortunately, such a wide range of ultrasonographic findings does not reflect a deep comprehension of sepsis-induced cardiomyopathy, but rather a lack of consensus about its definition. Several echocardiographic parameters intrinsically depend on loading conditions (both preload and afterload) so that it may be challenging to discriminate which is primitive and which is induced by hemodynamic perturbances. Here, we explore the state of the art in sepsis-related cardiomyopathy. We focus on the shortcomings in its definition and point out how cardiac performance dynamically changes in response to different hemodynamic clusters. A special attention is also given to update the knowledge about molecular mechanisms leading to myocardial dysfunction and that recall those of myocardial hibernation. Ultimately, the aim of this review is to highlight the unsolved issue in the field of sepsis-induced cardiomyopathy as their implementation would lead to improve risk stratification and clinical care.

Triiodothyronine enhances cardiac contractility in septic rats and probably through Akt-Caspase9 pathway to reduce septic-induced cardiomyocyte apoptosis

• A sufficiently severe hit by CLP caused sepsis-induced cardiomyopathy in rats. • Triiodothyronine improved myocardial atony and assisted to maintain hemodynamic stability in CLP rats. • Triiodothyronine exerted an antiapoptotic effect on septic cardiomyocytes, which was related to the Akt-Caspase9 pathway.

Abstract P3049: Age-independent Cardiac Protection By Pharmacological Activation Of Beclin-1 During Endotoxemia And Its Association With Energy Metabolic Reprogramming In Myocardium-A Targeted Metabolomics Study

Background: We previously showed that Beclin-1-dependent autophagy is cardiac protective in a rodent model of endotoxemia using young adult mice. In this report, we compared the potential therapeutic effects of pharmacological Beclin-1 activating peptide, TB-peptide, on the cardiac outcomes of young adult and aged mice during endotoxemia. We further examined alterations in myocardial metabolism induced by lipopolysaccharide (LPS) challenge with and without the TB-peptide treatment. Methods: C57BL/6J mice of 10-week and 24-month-old were challenged by LPS at doses at which cardiac dysfunction occurred. Following the treatment of TB-peptide or control vehicle, heart contractility, circulating cytokines, and myocardial autophagy were evaluated. A targeted metabolomics assay was applied to analyze cardiac metabolism. Results: TB-peptide boosted autophagic response, attenuated cytokine production, and improved cardiac performance in both young and aged mice during endotoxemia. A targeted metabolomics assay was designed to detect a pool of 361 known metabolites, of which 156 were detected in at least one of the heart tissue samples. LPS-induced impairments were found in glucose and amino acid (AA) metabolisms in mice of all ages, and TB-peptide provided ameliorative effects to rescue these alterations. However, lipid metabolites were upregulated in the young group but moderately downregulated in the aged by LPS, suggesting an age-dependent response. TB-peptide mitigated LPS-mediated trend of lipids in the young mice but provided little effect on the aged ones. Conclusion: Pharmacological activation of Beclin-1 by TB-peptide protects the heart in both young and aged population during endotoxemia, suggest a therapeutic potential for sepsis-induced cardiomyopathy. Metabolomics analysis suggests that this age-independent protection by TB-peptide is associated with reprograming of energy production via glucose and AA metabolisms.

Therapeutic Effects of Retinoic Acid in Lipopolysaccharide-Induced Cardiac Dysfunction: Network Pharmacology and Experimental Validation.

PurposeSepsis, which is deemed as a systemic inflammation reaction syndrome in the face of infectious stimuli, is the primary cause of death in ICUs. Sepsis-induced cardiomyopathy (SIC) may derive from systemic inflammation reaction and oxidative stress. Retinoic acid (RA) is recognized by its beneficial roles in terms of the immunoresponse to infections and antioxygen actions. However, the treatment efficacy and potential causal links of RA in SIC are still elusive.MethodsBy virtue of the STITCH database, we identified the targets of RA. Differentially expressed genes in SIC were acquired from the GEO database. The PPI network of intersected targets was established. GO and KEGG pathway enrichment analysis was completed. Hub genes were analyzed by cytoHubba plug-in. In the process of experimental validation, a mouse sepsis model was established by lipopolysaccharide (LPS), and the treated mice were intraperitoneally injected with RA or Dexamethasone (DEX) 60 min prior to LPS injections. Survival conditions, cardiac functions and antioxidant levels of the mice were assessed. Cardiac inflammation and injury were detected by HE and TUNEL. The levels of key genes and signal pathway expression were analyzed by RT-PCR and Western blot.ResultsPPARA, ITGAM, VCAM-1, IGF-1 and IL-6 were identified as key therapeutic targets of RA by network pharmacology. PI3K-Akt signaling pathway is the main regulatory pathway of RA. In vivo researches unraveled that RA can improve the survival rate and cardiac function of LPS-treated mice, inhibit inflammatory factors and myocardial injury, and regulate the expression of key therapeutic targets and key pathways, which is PI3K-Akt signaling pathway.ConclusionNetwork pharmacological method offers a predicative strategy to explore the treatment efficacy and causal links of RA in endotoxemic myocarditis. Through experimental verification, we discover that RA can reduce lipopolysaccharide-induced cardiac dysfunction by regulating the PI3K-Akt signaling pathway and key genes.

Dapagliflozin Protects H9c2 Cells Against Injury Induced by Lipopolysaccharide via Suppression of CX3CL1/CX3CR1 Axis and NF-κB Activity.

Dapagliflozin, a selective Sodium-glucose cotransporter-2 (SGLT2) inhibitor, has been shown to play a key role in the control and management of metabolic and cardiac diseases. The current study aims to address the effects of dapagliflozin on the expression of fractalkine (FKN), known as CX3CL1, and its receptors CX3CR1, Nuclear factor-kappa B(NF-κB) p65 activity, Reactive oxygen species (ROS), and inflammation in LPS-treated H9c2 cell line. H9c2 cells were cultured with lipopolysaccharide (LPS) to establish a model of LPS-induced damage, and then, subsequently were treated with dapagliflozin for 72 h. Our work included measurement of cell viability (MTT), Malondialdehyde (MDA), intracellular ROS, tumor necrosis factor-α (TNF-α), NF-κB activity, and expression of CX3CL1/CX3CR1. The results showed that LPS-induced reduction of cell viability was successfully rescued by dapagliflozin treatment. The cellular levels of MDA, ROS, and TNF-α, as an indication of cellular oxidative stress and inflammation, were significantly elevated in H9c2 cells compared to the control group. Furthermore, dapagliflozin ameliorated inflammation and oxidative stress through the modulation of the levels of MDA, TNF-α, and ROS. Correspondingly, dapagliflozin reduced the expression of CX3CL1/CX3CR1, NF-κB p65 DNA binding activity, and it also attenuated nuclear acetylated NF-κB p65 in LPS-induced injury in H9c2 cells compared to untreated cells. These findings shed light on the novel pharmacological potential of dapagliflozin in the alleviation of LPS-induced CX3CL1/CX3CR1-mediated injury in inflammatory conditions such as sepsis-induced cardiomyopathy.

Omaveloxolone attenuates the sepsis-induced cardiomyopathy via activating the nuclear factor erythroid 2-related factor 2

Sepsis-induced cardiomyopathy (SIC) is a common complication of sepsis and is the main reason for the high mortality in sepsis patients. More recent studies have indicated that activating nuclear factor erythroid 2-related factor 2 (Nrf2) signaling plays a protective role in SIC. As a potent activator of Nrf2, Omaveloxolone plays a pivotal role in defending against oxidative stress and the inflammatory response. Thus, we examined the efficacy of omaveloxolone in SIC. In the present study, the mice were injected intraperitoneally with a single dose of LPS (10 mg/kg) for 12 h to induce SIC. The data in our study indicated that omaveloxolone administration significantly improved cardiac injury and dysfunction in LPS-induced SIC. In addition, omaveloxolone administration reduced SIC-related cardiac oxidative stress, the inflammatory response and cardiomyocyte apoptosis in mice. In addition, omaveloxolone administration also improved LPS-induced cardiomyocyte injury in an in vitro model using H9C2 cells. Moreover, knockdown of Nrf2 by si-Nrf2 abolished the omaveloxolone-mediated cardioprotective effects. In conclusion, omaveloxolone has potent cardioprotective potential in treating sepsis and SIC via activation of the Nrf2 signaling pathway.

GYY4137 ameliorates sepsis-induced cardiomyopathy via NLRP3 pathway

Sepsis-induced cardiomyopathy (SICM) has a poor prognosis, with no effective therapeutic strategy currently. This study aimed to explore the mechanism underlying SICM and investigate the protective role of the hydrogen sulfide (H2S) donor GYY4137. This study included patients with SICM and animal models of SICM with wild-type and Nlrp3−/− mice, which were treated with or without GYY4137. Echocardiography, ELISA, TUNEL staining, and immunofluorescence were used to investigate phenotypic alterations. Serum levels of H2S and cytokines were measured. Inflammatory cell infiltration in the myocardial tissue was identified using immunohistochemistry and immunofluorescence. RNA expression profiles were identified using RNA sequencing. The protective mechanism of GYY4137 was further validated in the crosstalk between macrophages and cardiomyocytes using immunoblotting, real-time polymerase chain reaction (RT-PCR), and immunofluorescence when conditional medium of macrophages boosted by LPS were co-cultured with cardiomyocytes. Patients and animal models of SICM presented with lower serum H2S levels and heart dysfunction. GYY4137 reduced macrophage infiltration in septic heart tissue. GO analysis suggested that GYY4137 was involved in the inflammatory process. GYY4137 inhibited NLRP3 inflammasome activity in macrophages, reduced the secretion of inflammatory factors, and decreased the production of reactive oxygen species (ROS) in cardiomyocytes, thus exerting protective effects against SICM. We further found that the protective effects of GYY4137 were absent in Nlrp3-knockout models. GYY4137 ameliorates myocardial injury in SICM via the NLRP3 pathway by inhibiting the inflammatory response and reducing the production of myocardial ROS.

Feasibility and discriminatory value of tissue motion annular displacement in sepsis-induced cardiomyopathy: a single-center retrospective observational study

BackgroundThere is no formal diagnostic criterion for sepsis-induced cardiomyopathy (SICM), but left ventricular ejection fraction (LVEF) < 50% was the most commonly used standard. Tissue motion annular displacement (TMAD) is a novel speckle tracking indicator to quickly assess LV longitudinal systolic function. This study aimed to evaluate the feasibility and discriminatory value of TMAD for predicting SICM, as well as prognostic value of TMAD for mortality.MethodsWe conducted a single-center retrospective observational study in patients with sepsis or septic shock who underwent echocardiography examination within the first 24 h after admission. Basic clinical information and conventional echocardiographic data, including mitral annular plane systolic excursion (MAPSE), were collected. Based on speckle tracking echocardiography (STE), global longitudinal strain (GLS) and TMAD were, respectively, performed offline. The parameters acquisition rate, inter- and intra-observer reliability, time consumed for measurement were assessed for the feasibility analysis. Areas under the receiver operating characteristic curves (AUROC) values were calculated to assess the discriminatory value of TMAD/GLS/MAPSE for predicting SICM, defined as LVEF < 50%. Kaplan–Meier survival curve analysis was performed according to the cutoff values in predicting SICM. Cox proportional hazards model was performed to determine the risk factors for 28d and in-hospital mortality.ResultsA total of 143 patients were enrolled in this study. Compared with LVEF, GLS or MAPSE, TMAD exhibited the highest parameter acquisition rate, intra- and inter-observer reliability. The mean time for offline analyses with TMAD was significantly shorter than that with LVEF or GLS (p < 0.05). According to the AUROC analysis, TMADMid presented an excellent discriminatory value for predicting SICM (AUROC > 0.9). Patients with lower TMADMid (< 9.75 mm) had significantly higher 28d and in-hospital mortality (both p < 0.05). The multivariate Cox proportional hazards model revealed that BMI and SOFA were the independent risk factors for 28d and in-hospital mortality in sepsis cases, but TMAD was not.ConclusionSTE-based TMAD is a novel and feasible technology with promising discriminatory value for predicting SICM with LVEF < 50%.

A Prospective Observational Study to Determine Incidence and Outcome of Sepsis-induced Cardiomyopathy in an Intensive Care Unit.

Sepsis leads to left and/or right ventricular systolic and/or diastolic dysfunction resulting in adverse outcomes. Myocardial dysfunction can be diagnosed by echocardiography (ECHO) and early intervention can be planned. There are lacunae in Indian literature regarding the true incidence of septic cardiomyopathy and its influence on the outcome of patients admitted to intensive care unit (ICU). This prospective observational study was conducted on patients consecutively admitted with sepsis to the ICU of a tertiary care hospital in North India. In these patients, ECHO was performed after 48-72 hours to establish left ventricular (LV) dysfunction, in whom the ICU outcome was analyzed. The incidence of LV dysfunction was 14%. About 42.86% of patients had isolated systolic dysfunction, 7.14% of patients had isolated diastolic dysfunction, and 50.00% of patients had combined LV systolic and diastolic dysfunctions. The average days of mechanical ventilation in patients without LV dysfunction group (group I) was 2.41 ± 3.82 days as compared to 4.43 ± 4.27 days in patients with LV dysfunction (group II) (p = 0.034). Incidence of all-cause ICU mortality was 11 (12.79%) in group I and 3 (21.43%) in group II (p = 0.409). The mean duration of stay in ICU was 8.26 ± 4.41 days in group I as compared to 13.21 ± 6.83 days in group II. We concluded that sepsis-induced cardiomyopathy (SICM) in ICU is quite prevalent and clinically significant. All-cause ICU mortality and length of ICU stay are prolonged in patients with SICM. Bansal S, Varshney S, Shrivastava A. A Prospective Observational Study to Determine Incidence and Outcome of Sepsis-induced Cardiomyopathy in an Intensive Care Unit. Indian J Crit Care Med 2022;26(7):798-803.

Age-Independent Cardiac Protection by Pharmacological Activation of Beclin-1 During Endotoxemia and Its Association With Energy Metabolic Reprograming in Myocardium-A Targeted Metabolomics Study.

Background We showed that Beclin-1-dependent autophagy protects the heart in young and adult mice that underwent endotoxemia. Herein, we compared the potential therapeutic effects of Beclin-1 activating peptide, TB-peptide, on endotoxemia-induced cardiac outcomes in young adult and aged mice. We further evaluated lipopolysaccharide (lipopolysaccharide)-induced and TB-peptide treatment-mediated alterations in myocardial metabolism. Methods and Results C57BL/6J mice that were 10 weeks and 24 months old were challenged by lipopolysaccharide using doses at which cardiac dysfunction occurred. Following the treatment of TB-peptide or control vehicle, heart contractility, circulating cytokines, and myocardial autophagy were evaluated. We detected that TB-peptide boosted autophagy, attenuated cytokines, and improved cardiac performance in both young and aged mice during endotoxemia. A targeted metabolomics assay was designed to detect a pool of 361 known metabolites, of which 156 were detected in at least 1 of the heart tissue samples. Lipopolysaccharide-induced impairments were found in glucose and amino acid metabolisms in mice of all ages, and TB-peptide ameliorated these alterations. However, lipid metabolites were upregulated in the young group but moderately downregulated in the aged by lipopolysaccharide, suggesting an age-dependent response. TB-peptide mitigated lipopolysaccharide-mediated trend of lipids in the young mice but had little effect on the aged. (Study registration: Project DOI: https://doi.org/10.21228/M8K11W). Conclusions Pharmacological activation of Beclin-1 by TB-peptide is cardiac protective in both young and aged population during endotoxemia, suggest a therapeutic potential for sepsis-induced cardiomyopathy. Metabolomics analysis suggests that an age-independent protection by TB-peptide is associated with reprograming of energy production via glucose and amino acid metabolisms.

The molecular and metabolic landscape of iron and ferroptosis in cardiovascular disease.

The maintenance of iron homeostasis is essential for proper cardiac function. A growing body of evidence suggests that iron imbalance is the common denominator in many subtypes of cardiovascular disease. In the past 10 years, ferroptosis, an iron-dependent form of regulated cell death, has become increasingly recognized as an important process that mediates the pathogenesis and progression of numerous cardiovascular diseases, including atherosclerosis, drug-induced heart failure, myocardial ischaemia–reperfusion injury, sepsis-induced cardiomyopathy, arrhythmia and diabetic cardiomyopathy. Therefore, a thorough understanding of the mechanisms involved in the regulation of iron metabolism and ferroptosis in cardiomyocytes might lead to improvements in disease management. In this Review, we summarize the relationship between the metabolic and molecular pathways of iron signalling and ferroptosis in the context of cardiovascular disease. We also discuss the potential targets of ferroptosis in the treatment of cardiovascular disease and describe the current limitations and future directions of these novel treatment targets.

Therapeutic Strategies Targeting Mitochondrial Dysfunction in Sepsis-induced Cardiomyopathy.

Sepsis is an increasingly worldwide problem; it is currently regarded as a complex life-threatening dysfunction of one or more organs as a result of dysregulated host immune response to infections. The heart is one of the most affected organs, as roughly 10% to 70% of sepsis cases are estimated to turn into sepsis-induced cardiomyopathy (SIC). SIC can be defined as a reversible myocardial dysfunction characterized by dilated ventricles, impaired contractility, and decreased ejection fraction. Mitochondria play a critical role in the normal functioning of cardiac tissues as the heart is highly dependent on its production of adenosine triphosphate (ATP), its damage during SIC includes morphology impairment, mitophagy, biogenesis disequilibrium, electron transport chain disturbance, molecular damage from the actions of pro-inflammatory cytokines and many other different impairments that are major contributing factors to the severity of SIC. Although mitochondria-targeted therapies usage is still inadequate in clinical settings, the preclinical study outcomes promise that the implementation of these therapies may effectively treat SIC. This review summarizes the different therapeutic strategies targeting mitochondria structure, quality, and quantity abnormalities for the treatment of SIC.

MicroRNAs Promote the Progression of Sepsis-Induced Cardiomyopathy and Neurovascular Dysfunction Through Upregulation of NF-kappaB Signaling Pathway-Associated HDAC7/ACTN4.

IntroductionThe objective of this study was to determine the NF-kappaB pathway, hub genes, and transcription factors (TFs) in monocytes implicated in the progression of neurovascular-related sepsis-induced cardiomyopathy (SIC) as well as potential miRNAs with regulatory functions.Methods: Sepsis-induced cardiomyopathy—and heart failure (HF)-related differentially expressed genes (DEGs) between SIC and HF groups were identified separately by differential analysis. In addition, DEGs and differentially expressed miRNAs (DEmiRNAs) in monocytes between sepsis and the HC group were identified. Then, common DEGs in SIC, HF, and monocyte groups were identified by intersection analysis. Based on the functional pathways enriched by these DEGs, genes related to the NF-kB-inducing kinase (NIK)/NF-kappaB signaling pathway were selected for further intersection analysis to obtain hub genes. These common DEGs, together with sepsis-related DEmiRNAs, were used to construct a molecular interplay network and to identify core TFs in the network.Results: A total of 153 upregulated genes and 25 downregulated genes were obtained from SIC-, HF-, and monocyte-related DEGs. Functional pathway analysis revealed that the upregulated genes were enriched in NF-κB signaling pathway. A total of eight genes associated with NF-κB signaling pathway were then further identified from the 178 DEGs. In combination with sepsis-related DEmiRNAs, HDAC7/ACTN4 was identified as a key transcriptional regulatory pair in the progression of SIC and in monocyte regulation. hsa-miR-23a-3p, hsa-miR-3175, and hsa-miR-23b-3p can regulate the progression of SIC through the regulation of HDAC7/ACTN4. Finally, gene set enrichment analysis (GSEA) suggested that HDAC7/ACTN4 may be associated with apoptosis in addition to the inflammatory response.Conclusion: hsa-miR-23a-3p, hsa-miR-3175, and hsa-miR-23b-3p are involved in SIC progression by regulating NF-κB signaling signaling pathway-related HDAC7/ACTN4 in monocytes and cardiac tissue cells. These mechanisms may contribute to sepsis-induced neurovascular damage.