Sepsis-induced Cardiomyopathy Research Articles

Sepsis-Associated Cardiomyopathy: Long-Term Prognosis, Management, and Guideline-Directed Medical Therapy.

To explore the definitions of sepsis-induced cardiomyopathy and how that impacts interpretation of the available data and considerations of long-term prognosis and management. The field of sepsis-induced cardiomyopathy has been hampered by lack of consensus about its proper definition, with a great deal of heterogeneity in clinical trial data in both individual studies and meta-analyses and consequent disparity of estimates of incidence, prognosis, and clinical significance. New diagnostic techniques, while potentially shedding light on pathophysiology, have only exacerbated these challenges. There are few persuasive data to suggest that decreased ejection fraction consequent to sepsis-induced cardiomyopathy merits a treatment strategy different from other causes, except that improvement may be more likely inasmuch as the classic description includes reversibility over 7 to 10 days. For persistent cardiac dysfunction after sepsis, whether pre-existing or newly diagnosed, institution and titration of guideline-directed medical therapy for HFrEF seems to be the most logical strategy. Armed with a clear understanding of what parameters of cardiac function are most important, clinicians can develop therapeutic strategies that make sense and calibrate them according to the clinical response.

Sepsis-Induced Cardiomyopathy Secondary to Escherichia coli Sepsis and Intestinal Perforation: A Diagnostic Challenge in a Paediatric Patient

Sepsis-Induced Cardiomyopathy Secondary to Escherichia coli Sepsis and Intestinal Perforation: A Diagnostic Challenge in a Paediatric Patient

Molecular and metabolic landscape of adenosine triphosphate-induced cell death in cardiovascular disease.

The maintenance of intracellular and extracellular adenosine triphosphate (ATP) levels plays a pivotal role in cardiac function. In recent years, burgeoning attention has been directed towards ATP-induced cell death (AICD), revealing it as a distinct cellular demise pathway triggered by heightened extracellular ATP concentrations, distinguishing it from other forms of cell death such as apoptosis and necrosis. AICD is increasingly acknowledged as a critical mechanism mediating the pathogenesis and progression of various cardiovascular maladies, encompassing myocardial ischemia-reperfusion injury, sepsis-induced cardiomyopathy, hypertrophic cardiomyopathy, arrhythmia, and diabetic cardiomyopathy. Consequently, a comprehensive understanding of the molecular and metabolic underpinnings of AICD in cardiac tissue holds promise for the prevention and amelioration of cardiovascular diseases. This review first elucidates the vital physiological roles of ATP in the cardiovascular system, subsequently delving into the intricate molecular mechanisms and metabolic signatures governing AICD. Furthermore, it addresses the potential therapeutic targets implicated in mitigating AICD for treating cardiovascular diseases, while also delineating the current constraints and future avenues for these innovative therapeutic targets, thereby furnishing novel insights and strategies for the prevention and management of cardiovascular disorders.

Machine learning for predicting acute myocardial infarction in patients with sepsis.

Acute myocardial infarction (AMI) and sepsis are the leading causes of high mortality rates in intensive care units. While sepsis frequently affects the cardiovascular system, distinguishing between sepsis-induced cardiomyopathy and AMI remains challenging due to overlapping biomarkers. Misdiagnosis can hinder timely treatment and increase risk of complications. This study used multidimensional clinical data and machine learning techniques to develop and validate a novel predictive model for identifying AMI in critically ill patients with sepsis. Data from patients with sepsis were extracted from the Medical Information Mart for Intensive Care-IV database. Six machine learning algorithms were employed for model construction. Additionally, the machine learning-based models were compared with traditional scoring systems. Model performance was evaluated in terms of discrimination, calibration, and clinical applicability. In total, 2,103 critically ill patients with sepsis were included, 459 (21.8%) of whom experienced AMI during hospitalization. A total of 26 variables were selected for model construction. Among all models, the Gradient Boosting Classifier model demonstrated the best predictive performance in terms of discrimination, calibration, and clinical applicability. Machine learning models have the potential to serve as tools for predicting AMI in patients with sepsis. The Gradient Boosting Classifier model developed herein demonstrated promising predictive performance, supporting clinicians in identifying patients at high-risk of sepsis and implementing early interventions to reduce mortality rates.

The Complexities of Sepsis-Induced Cardiomyopathy: A Clinical Case and Review of Inflammatory Pathways and Potential Therapeutic Targets

The Complexities of Sepsis-Induced Cardiomyopathy: A Clinical Case and Review of Inflammatory Pathways and Potential Therapeutic Targets

Identification and verification of feature biomarkers associated with choline metabolism in sepsis-induced cardiomyopathy.

Background: Sepsis-induced cardiomyopathy (SIC), one of the most common complications of sepsis, seriously affects the prognosis of critically ill patients. Choline metabolism is an important biological process in the organism, and the mechanism of its interaction with SIC is unclear. The aim of this study was to reveal the choline metabolism genes (CMGs) associated with SIC and to provide effective targets for the treatment of SIC.Methods: Through a comprehensive analysis of the microarray dataset GSE79962 (comprising 20 SIC patients and 11 healthy controls) from the GEO database, suspected co-expression modules and differentially expressed genes (DEGs) in SIC were identified. Hub CMGs were obtained by intersecting choline metabolism database with DEGs and key model genes. Afterward, hub CMGs most significantly involved in prognosis were further analyzed for the verification of major pathways of enrichment analysis. Finally, the expression of hub CMGs in in vivo and in vitro SIC model was verified by immunohistochemistry staining and quantitative real-time polymerase chain reaction analysis (qPCR).Results: WGCNA identified 1 hub gene panel and 3867 hub genes, which were intersected with DEGs and CMGs to obtain the same 3 hub CMGs:HIF-1α, DGKD and PIK3R1. Only HIF-1α shows significant association with mortality (P = 0.009). Subsequent differential analysis based on the high and low HIF-1α expression yielded 63 DEGs and then they were uploaded into Cytoscape software to construct a protein-protein interaction (PPI) network and 6 hub genes with the highest priority were obtained (CISH, THBS1, IMP1, MYC, SOCS3 and VCAN). Finally, a multifactorial COX analysis revealed a significant correlation between HIF-1α and survival in SIC patients, which was further validated by in vitro and in vivo experiments.Conclusion: Our findings will provide new insights into the pathogenesis of SIC, and HIF-1α may have important applications as a potential biomarker for early detection and therapeutic intervention in SIC.

Sepsis-induced cardiomyopathy: understanding pathophysiology and clinical implications.

Sepsis is a life-threatening form of organ dysfunction resulting from a dysregulated response to infection. The complex pathogenesis of sepsis poses challenges because of the lack of reliable biomarkers for early identification and effective treatments. As sepsis progresses to severe forms, cardiac dysfunction becomes a major concern, often manifesting as ventricular dilation, a reduced ejection fraction, and a diminished contractile capacity, known as sepsis-induced cardiomyopathy (SIC). The absence of standardized diagnostic and treatment protocols for SIC leads to varied criteria being used across medical institutions and studies, resulting in significant outcome disparities. Despite the high prevalence of SIC, accurate statistical data are lacking. To understand how SIC affects sepsis prognosis, a thorough exploration of its pathophysiological mechanisms, including systemic factors and complex signalling within myocardial and immune cells, is required. Identifying the factors influencing SIC occurrence and progression is crucial and must be conducted within specific clinical contexts. In this review, the clinical manifestations, pathophysiological mechanisms, and treatment strategies for SIC are discussed, along with the clinical background. We aim to connect current practices with future research challenges, providing clear guidance for clinicians and researchers.

Regulation of mitochondrial autophagy by lncRNA MALAT1 in sepsis-induced myocardial injury

BackgroundSepsis-induced myocardial injury (SIMI) is a severe complication of sepsis, contributing significantly to mortality. Mitochondrial dysfunction and dysregulated autophagy are implicated in SIMI pathogenesis. Long non-coding RNA MALAT1 has been associated with various diseases, including sepsis, but its role in SIMI remains unclear.ObjectiveThis study aimed to investigate the role of lncRNA MALAT1 in SIMI, specifically in the regulation of mitochondrial autophagy.MethodsA sepsis-induced cardiomyopathy model was established in mice, and the cardiac tissues were analyzed. The expression of lncRNA MALAT1 was modulated and its effects on mitochondrial autophagy, myocardial injury, inflammation, and apoptosis were assessed. Furthermore, the interaction between MALAT1 and miR-146a was explored, as well as the involvement of the TLR4/NF-kB/MAPK signaling pathway.ResultsActivation of mitochondrial autophagy by urolithin A (UA) alleviated SIMI, inflammation, and cardiac dysfunction. Downregulation of MALAT1 enhanced mitochondrial autophagy, stabilized the mitochondrial membrane potential, and inhibited mitochondrial reactive oxygen species (ROS) production, leading to improved cell viability and reduced myocardial injury. Furthermore, MALAT1 interacted with miR-146a, and their modulation influenced mitochondrial autophagy, myocardial injury, and inflammation. The TLR4/NF-kB/MAPK signaling pathway was implicated in these processes.ConclusionOur findings suggest that lncRNA MALAT1 plays a crucial role in SIMI by modulating miR-146a-mediated mitochondrial autophagy and the TLR4/NF-kB/MAPK signaling pathway. These results provide new insights into the pathogenesis of SIMI and potential therapeutic targets.

Metoprolol use is associated with improved outcomes in patients with sepsis-induced cardiomyopathy: an analysis of the MIMIC-IV database

BackgroundMetoprolol is commonly administered to critically ill patients; however, its effect on mortality in patients with sepsis-induced cardiomyopathy (SICM) remains uncertain. This study aimed to investigate the relationship between metoprolol use and mortality in patients with SICM.MethodsAdults with SICM were identified from the MIMIC-IV database. The exposure of interest was metoprolol treatment. The outcomes assessed were 30-day mortality, 1-year mortality, and in-hospital mortality. Kaplan–Meier survival analysis evaluated the effect of metoprolol on these outcomes. Multivariable Cox proportional hazards and logistic regression analyses were performed to determine the correlation between metoprolol treatment and mortality in patients with SICM.Results1163 patients with SICM were identified, with 882 receiving metoprolol treatment (MET group) and 281 not receiving metoprolol treatment (NOMET group). Overall, the 30-day, 1-year, and in-hospital mortality rates were 10.2%, 18.2%, and 8.9%, respectively. Significant differences in mortality existed between the groups. Multivariable Cox analysis revealed that patients in the NOMET group had a higher risk of 1-year mortality (adjusted hazard ratio [HR] 2.493; 95% confidence interval [CI] 1.800–3.451; P < 0.001) and 30-day mortality (adjusted HR 4.280; 95%CI 2.760–6.637; P < 0.001). Metoprolol treatment was associated with lower in-hospital mortality (odds ratio [OR] 5.076; 95% CI 2.848–9.047; P < 0.001). Subgroup analysis supported these findings.ConclusionMetoprolol treatment is associated with reduced all-cause mortality in patients with SICM. Prospective studies are required to validate these findings.

Potential Roles of IP3 Receptors and Calcium in Programmed Cell Death and Implications in Cardiovascular Diseases.

Inositol 1,4,5-trisphosphate receptors (IP3Rs) play a crucial role in maintaining intracellular/cytosolic calcium ion (Ca2+i) homeostasis. The release of Ca2+ from IP3Rs serves as a second messenger and a modulatory factor influencing various intracellular and interorganelle communications during both physiological and pathological processes. Accumulating evidence from in vitro, in vivo, and clinical studies supports the notion that the overactivation of IP3Rs is linked to the pathogenesis of various cardiac conditions. The overactivation of IP3Rs results in the dysregulation of Ca2+ concentration ([Ca2+]) within cytosolic, mitochondrial, and nucleoplasmic cellular compartments. In cardiovascular pathologies, two isoforms of IP3Rs, i.e., IP3R1 and IP3R2, have been identified. Notably, IP3R1 plays a pivotal role in cardiac ischemia and diabetes-induced arrhythmias, while IP3R2 is implicated in sepsis-induced cardiomyopathy and cardiac hypertrophy. Furthermore, IP3Rs have been reported to be involved in various programmed cell death (PCD) pathways, such as apoptosis, pyroptosis, and ferroptosis underscoring their multifaceted roles in cardiac pathophysiology. Based on these findings, it is evident that exploring potential therapeutic avenues becomes crucial. Both genetic ablation and pharmacological intervention using IP3R antagonists have emerged as promising strategies against IP3R-related pathologies suggesting their potential therapeutic potency. This review summarizes the roles of IP3Rs in cardiac physiology and pathology and establishes a foundational understanding with a particular focus on their involvement in the various PCD pathways within the context of cardiovascular diseases.

Prognostic value of red blood cell distribution width in sepsis induced cardiomyopathy patients.

The potential association between red blood cell distribution width (RDW) at admission and prognosis in patients with sepsis-induced cardiomyopathy(SIC) remains uncertain. The purpose of this study was to explore the prognostic value of RDW on mortality in patients with SIC. Data for this retrospective study were obtained from the MIMIC IV2.2 database. We used propensity score matching (PSM) and Cox proportional hazards regression analysis to evaluate the main risk factors associated with mortality in SIC patients. This analysis was utilized to develop a predictive nomogram. To assess the predictive accuracy and clinical usefulness of the model, we employed the concordance index (C-index) and decision curve analysis. To define the high- and low-RDW groups among patients with SIC, we determined the optimal cut-off value by maximizing the Youden index. According to the screening criteria, we identified a cohort of 1051 patients diagnosed with SIC. When comparing the high-RDW group to the low-RDW group, it was found that the high-RDW group exhibited longer Los_ICU(4.5 days vs.3.8 days, respectively, P = 0.009) and higher mortality rates at 28 days (33.8% vs. 7.8%, respectively, P < 0.001). A nomogram model was created using matched patients which included various factors such as Age, RDW, LDH, CKMB, creatinine and the administration of β-blocker. The C-index predicting 28-day survival probability was 0.846. Decision curves analysis demonstrated that the inclusion of RDW in the model provided a greater net benefit compared to excluding RDW. The prognosis of patients with SIC can be predicted by the RDW value. The nomogram model provides a useful tool in identifying and managing SIC patients.

Po-Ge-Jiu-Xin decoction alleviate sepsis-induced cardiomyopathy via regulating phosphatase and tensin homolog-induced putative kinase 1 /parkin-mediated mitophagy

Ethnopharmacological relevanceSepsis is a life-threatening systemic syndrome usually accompanied by myocardial dysfunction. Po-Ge-Jiu-Xin decoction (PGJXD), a traditional Chinese prescription medicine, has been used clinically to treat cardiovascular disease including heart failure, sepsis-induced cardiomyopathy (SIC) and even septic shock. Previous clinical studies suggested PGJXD has shown promising results in improving cardiac function and treating heart failure in sepsis. However, more research is needed to elucidate the mechanisms underlying PGJXD's therapeutic effects in sepsis-induced cardiomyopathy. Materials and methodsInitially, we identified the major compounds of PGJXD through ultra-performance liquid chromatography-mass spectrometry technology analysis. We established in a SIC rat model using cecal ligation and puncture(CLP) and treated by PGJXD and levosimendan. We evaluated pathological damage by hematoxylin and eosin staining and measured serum myocardial injury biomarkers. Myocardial apoptosis was detected by Tunel staining and quantifying specific biomarker protein levels. Subsequently, we evaluated myocardium mitochondrial quality using Transmission electron microscope (TEM), antioxidant stress indexes and tissue adenosine triphosphate(ATP) content. We detected the expression of phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1), parkin, LC3, and p62 using Western blotting and Quantitative real time polymerase chain reaction(qRT-PCR). (Lipopolysaccharides, LPS)-induced H9c2 cell model was established to further explore the mechanism of PGJXD on SIC. In addition to measuring cell viability, we measured mitochondrial membrane potential using JC-1 staining. Additionally, Parkin-siRNA transfected into H9c2 cells to validate whether PGJXD conducted protective effects against SIC through PINK1/Parkin-mediated mitophagy. ResultsIt has been demonstrated that PGJXD reduced mortality in septic rat, contributed to ameliorating myocardium injury, suppressed inflammatory response and ameliorated the myocardial apoptosis. PGJXD could also alleviate mitochondrial structural abnormality, mitigated oxidative stress injury and promoted energy synthesis in CLP models. Western blotting and qRT-PCR have further confirmed that PGJXD can activate PINK1/parkin pathway-mediated mitophagy, resulting in preserving mitochondrial quality in the myocardium. Furthermore, Parkin siRNA partially reversed the beneficial effect of PGJXD on mitochondrial fission/fusion and mitophagy in vitro. Therefore, the cardioprotective effect of PGJXD is achieved by inducing PINK1/Parkin-mediated mitophagy in maintaining mitochondrial homeostasis. ConclusionsThese results suggest that the potential therapeutic effect of PGJXD on cardiac dysfunction during sepsis and support its mechanism of targeted induction of PINK1-Parkin-mediated mitophagy.

ACE2 alleviates sepsis-induced cardiomyopathy through inhibiting M1 macrophage via NF-κB/STAT1 signals

Angiotensin-converting enzyme 2 (ACE2), a crucial element of the renin-angiotensin system (RAS), metabolizes angiotensin II into Ang (1–7), which then combines with the Mas receptor (MasR) to fulfill its protective role in various diseases. Nevertheless, the involvement of ACE2 in sepsis-induced cardiomyopathy (SIC) is still unexplored. In this study, our results revealed that CLP surgery dramatically impaired cardiac function accompanied with disruption of the balance between ACE2-Ang (1–7) and ACE-Ang II axis in septic heart tissues. Moreover, ACE2 knockin markedly alleviated sepsis induced RAS disorder, cardiac dysfunction and improved survival rate in mice, while ACE2 knockout significantly exacerbates these outcomes. Adoptive transfer of bone marrow cells and in vitro experiments showed the positive role of myeloid ACE2 by mitigating oxidative stress, inflammatory response, macrophage polarization and cardiomyocyte apoptosis by blocking NF-κB and STAT1 signals. However, the beneficial impacts were nullified by MasR antagonist A779. Collectively, these findings showed that ACE2 alleviated SIC by inhibiting M1 macrophage via activating the Ang (1–7)-MasR axis, highlight that ACE2 might be a promising target for the management of sepsis and SIC patients.

ZC3H13 may participate in the ferroptosis process of sepsis-induced cardiomyopathy by regulating the expression of Pnn and Rbm25

BackgroundN6 methyladenosine (m6A) regulates the ferroptosis in different diseases. However, there is no report about the role of the m6A regulator in the ferroptosis process of septic cardiomyopathy (SCM). This study aims to find the potential m6A regulator that participates in the ferroptosis process of SCM. MethodsGenes related to m6A were identified through bioinformatics analysis in GSE142615. Then, the expression of Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13 was detected in lipopolysaccharide (LPS)-treated HL-1 cells using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). After overexpression or interference with ZC3H13, Cell Counting Kit-8 measured cell proliferation, flow cytometry detected apoptosis and reactive oxygen species (ROS) accumulation was observed. Then, we identified the potential downstream genes of ZC3H13 through further bioinformatics analysis followed by qRT-PCR and western blotting validation. ResultsThere were five differentially expressed genes related to m6A, including Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13. The expression of Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13 mRNA was significantly up-regulated in the LPS-treated HL-1 cells, with ZC3H13 having the highest expression. Furthermore, overexpression of ZC3H13 inhibited the proliferation of HL-1 cells and promoted apoptosis and ROS accumulation. While, interfering with ZC3H13 promoted the proliferation of LPS-treated HL-1 cells, and reduced apoptosis and ROS accumulation. Additionally, si-ZC3H13 promoted the expression of Pnn, GPX4, and SLC7A11; while inhibiting the expression of Rbm25 and Caspase 3. ConclusionsIn a word, the silence of ZC3H13 increased the proliferation and ferroptosis-related protein expression, decreased apoptosis and ROS accumulation, as well as maybe by regulating Pnn and Rbm25 expression.

Heart-type fatty acid binding protein (H-FABP) as an early biomarker in sepsis-induced cardiomyopathy: a prospective observational study

BackgroundSepsis-induced cardiomyopathy (SICM) is a common and life-threatening complication of sepsis, significantly contributing to elevated mortality. This study aimed to identify crucial indicators for the prompt and early assessment of SICM.MethodsPatients diagnosed with sepsis or SICM within 24 h of intensive care unit (ICU) admission were enrolled in this prospective observational study. Patients were assigned to the training set, validation set and external test set. The primary endpoint was 7-day ICU mortality, and the secondary endpoint was 28-day ICU mortality. Three machine learning algorithms were utilized to identify relevant indicators for diagnosing SICM, incorporating 64 indicators including serum biomarkers associated with cardiac, renal, and liver function, lipid metabolism, coagulation, and inflammation. Internal and external validations were performed on the screening results. Patients were then stratified based on the cut-off value of the most diagnostically effective biomarker identified, and their prognostic outcomes were observed and analyzed.ResultsA total of 270 patients were included in the training and validation set, and 52 patients were included in the external test set. Age, sex, and comorbidities did not significantly differ between the sepsis and SICM groups (P > 0.05). The support vector machine (SVM) algorithm identified six indicators with an accuracy of 84.5%, the random forest (RF) algorithm identified six indicators with an accuracy of 81.9%, and the logistic regression (LR) algorithm screened out seven indicators. Following rigorous selection, a diagnostic model for sepsis-induced cardiomyopathy was established based on heart-type fatty acid binding protein (H-FABP) (OR 1.308, 95% CI 1.170–1.462, P < 0.001) and retinol-binding protein (RBP) (OR 1.020, 95% CI 1.006–1.034, P < 0.05). H-FABP alone exhibited the highest diagnostic performance in both the internal (AUROC 0.689, P < 0.05) and external sets (AUROC 0.845, P < 0.05). Patients with SICM were further stratified based on an H-FABP diagnostic cut-off value of 8.335 ng/mL. Kaplan–Meier curve analysis demonstrated that elevated H-FABP levels at admission were associated with higher 7-day ICU mortality in patients with SICM (P < 0.05).ConclusionsThis study revealed that H-FABP concentrations measured within 24 h of patient admission could serve as a crucial biomarker for the early and rapid diagnosis and short-term prognostic evaluation of SICM.

Inhibition of miR-194-5p avoids DUSP9 downregulation thus limiting sepsis-induced cardiomyopathy

Sepsis-induced cardiomyopathy (SIC) is described as a reversible myocardial depression that occurs in patients with septic shock. Increasing evidence shows that microRNA-194-5p (miR-194-5p) participates in the regulation of oxidative stress, mitochondrial dysfunction, and apoptosis and its expression is associated with the occurrence and progression of cardiovascular disease; however, the effects of miR-194-5p in SIC are still unclear. This study explores whether miR-194-5p could modulate SIC by affecting oxidative stress, mitochondrial function, and apoptosis. Experimental septic mice were induced by intraperitoneal injection of lipopolysaccharide (LPS) in C57BL/6J mice. The biological role of miR-194-5p in SIC in vivo was investigated using cardiac echocardiography, ELISA, western blot, qRT-PCR, transmission electron microscopy, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, bioinformatics analysis, and dual-luciferase reporter gene assay. Our major finding is that miR-194-5p antagomir mitigates sepsis-induced cardiac dysfunction, inflammation, oxidative stress, apoptosis and mitochondrial dysfunction in the hearts of septic mice, while miR-194-5p agomir triggers the opposite effects. Furthermore, dual-specificity phosphatase 9 (DUSP9) is a direct target of miR-194-5p and the cardioprotective effects of miR-194-5p antagomir on cardiac dysfunction, inflammation, apoptosis, mitochondrial dysfunction and oxidative stress are abolished through inhibiting DUSP9. Therefore, miR-194-5p inhibition could mitigate SIC via DUSP9 in vivo and the novel miR-194-5p/DUSP9 axis might be the potential treatment targets for SIC patients.

Time of day-dependent alterations of ferroptosis in LPS-induced myocardial injury via Bmal-1/AKT/ Nrf2 in rat and H9c2 cell

BackgroundOne of the most prevalent causes of death in sepsis is sepsis-induced cardiomyopathy (SICM). Circadian disruption is involved in the progress of sepsis. However, the molecular mechanism remains unclear. MethodsHere, we built LPS-induced SICM in-vivo and in-vitro models. LPS was administrated at the particular Zeitgeber times (ZT), ZT4-ZT10-ZT16-ZT22 and ZT10-ZT22 in vivo and vitro experiments, respectively. ResultsIn vivo experiment, injection of LPS at ZT10 induced higher infiltration of inflammatory cells and content of intracellular Fe2+, and lower level of Glutathione peroxidase 4 (GPX4) and cardiac function than other ZTs (P < 0.05), which indicated that myocardial ferroptosis in septic rat presented a time of day-dependent manner. Bmal-1 protein and mRNA levels of injection of LPS at ZT10 were lower than those at other three ZTs (P < 0.05). The ratios of pAKT/AKT at ZT4 and ZT10 LPS injection were lower than those at ZT16 and ZT22 (P < 0.05). Nrf2 protein levels at ZT10 LPS injection were lower than those at other three ZTs (P < 0.05). These results indicated that the circadian of Bmal-1 and its downstream AKT/Nrf2 pathway in rat heart were inhibited under SICM condition. Consistent with in-vivo experiment, we found LPS could significantly reduce the expressions of Bmal-1 protein and mRNA in H9c2 cell. Up-regulation of Bmal-1 could reduce the cell death, oxidative stress, ferroptosis and activation of AKT/Nrf2 pathway at both ZT10 and ZT22 LPS administration. Conversely, its down-regulation presented opposite effects. AKT siRNA could weaken the effect of Bmal-1 pcDNA. ConclusionFerroptosis presented the time of day-dependent manners via Bmal-1/AKT/Nrf2 in vivo and vitro models of SICM.

Erbin alleviates sepsis-induced cardiomyopathy by inhibiting RIPK1-dependent necroptosis through activating PKA/CREB pathway

Sepsis is a systemic inflammatory disease that can cause multiple organ damage. Septic patients with cardiac dysfunction have a significantly higher mortality. Based on the results of bioinformatics analysis, weighted gene co-expression network analysis (WGCNA), we found that Erbin is vital in cardiomyocyte. However, the function of Erbin in sepsis-induced cardiomyopathy (SIC) has not been explicitly studied. We discussed the role of Erbin in SIC by employing the Erbin−/− mice and HL-1 cardiomyocyte. An in vitro model of inflammation in HL-1 was used to confirm stimulation with lipopolysaccharide (LPS) and a mouse model of cecal ligation and puncture (CLP) to study the molecular mechanisms under SIC. Transmission electron microscopy (TEM) was used to characterize the morphological characteristics at the ultrastructural level. The expressions of Erbin, p-RIPK1, RIPK1, p-RIPK3, RIPK3, p-MLKL, MLKL, p-PKA, PKA, p-CREB and CREB were detected by western blot. qPCR analysis was applied to detect TNF-α, IL-1β, IL-6, RIPK1 and MLKL mRNA expression. Cell survival was detected by CCK-8 assay and the levels of c TnI concentration were detected by ELISA kit. Our study revealed that necroptosis and inflammation were activated in cardiomyocytes during sepsis and deficiency of Erbin aggravated them. Furthermore, deficiency of Erbin exacerbated systolic dysfunction including the decline of LVEF and LVFS induced by CLP. Overexpression of Erbin alleviated necroptosis and inflammation by activating PKA/CREB pathway. Our research elucidates a noval mechanism whereby Erbin participates in SIC, providing a promising therapeutic target for myocardial dysfunction during sepsis.

In vivo and in vitro study on the regulatory mechanism of XiaoChaiHu decoction on PANoptosis in sepsis-induced cardiomyopathy

Ethnopharmacological relevanceIn accordance with the tenets of traditional Chinese medicine, sepsis is categorized into three distinct syndromes: heat syndrome, blood stasis syndrome, and deficiency syndrome. Xiaochaihu decoction (XCHD) has many functions, including the capacity to protect the liver, cholagogue, antipyretic, anti-inflammatory, and anti-pathogenic microorganisms. XCHD exerts the effect of clearing heat and reconciling Shaoyang. The XCHD contains many efficacious active ingredients, yet the mechanism of sepsis-induced cardiomyopathy (SIC) remains elusive. Aim of the studyTo investigate the molecular mechanisms underlying the protective effects of XCHD against SIC using an integrated approach combining network pharmacology and molecular biology techniques. Materials and methodsNetwork pharmacology methods identified the active ingredients, target proteins, and pathways affected by XCHD in the context of SIC. We conducted in vivo experiments using mice with lipopolysaccharide-induced SIC, evaluating cardiac function through echocardiography and histology. XCHD-containing serum was analyzed to determine its principal active components using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The effects of XCHD-containing serum on SIC were further tested in vitro in LPS-treated H9c2 cardiac cells. Protein expression levels were quantified via Western blotting and enzyme-linked immunosorbent assay (ELISA). Additionally, molecular docking was performed between the active components and ZBP1, a potential target protein. Overexpression of ZBP1 in H9c2 cells allowed for a deeper exploration of its role in modulating SIC-associated gene expression. ResultsUPLC-MS/MS identified 31 shared XCHD and XCHD-containing serum components. These included organic acids, terpenoids, and flavonoids, which have been identified as the active components of XCHD. Our findings revealed that XCHD alleviated LPS-induced myocardial injury, improved cardiac function, and preserved cardiomyocyte morphology in mice. In vitro studies, we demonstrated that XCHD-containing serum significantly suppressed the expression of inflammatory cytokines (IL-6, IL-1β, and TNF-α) in LPS-induced H9c2 cells. Mechanistic investigations showed that XCHD downregulated genes associated with PANoptosis, a novel cell death pathway, suggesting its protective role in sepsis-damaged hearts. Conversely, overexpression of ZBP1 abolished the protective effects of XCHD and amplified PANoptosis-related gene expression. ConclusionsOur study provides the first evidence supporting the protective effects of XCHD against SIC, both in vitro and in vivo. The underlying mechanism involves the inhibition of ZBP1-initiated PANoptosis, offering new insights into treating SIC using XCHD.

GDF15 attenuates sepsis-induced myocardial dysfunction by inhibiting cardiomyocytes ferroptosis via the SOCS1/GPX4 signaling pathway

Sepsis is a systemic inflammatory response syndrome triggered by infection, presenting with symptoms such as fever, increased heart rate, and low blood pressure. In severe cases, it can lead to multiple organ dysfunction, posing a life-threatening risk. Sepsis-induced cardiomyopathy (SIC) is a critical factor in the poor prognosis of septic patients, leading to myocardial dysfunction characterized by cell death, inflammation, and diminished cardiac function. Ferroptosis, an iron-dependent form of programmed cell death, is a key mechanism causing cardiomyocyte damage in SIC. Growth differentiation factor 15 (GDF15), a member of the TGF-β superfamily, is associated with various cardiovascular diseases and can inhibit oxidative stress, reduce reactive oxygen species (ROS), and suppress ferroptosis. Elevated serum GDF15 levels in sepsis are correlated with organ injuries, suggesting its potential as a therapeutic target. However, its role and mechanisms in SIC remain unclear. Glutathione peroxidase 4 (GPX4), the only enzyme capable of reducing lipid peroxides within cells, protects cells by reducing lipid peroxidation levels and inhibiting ferroptosis. Investigating the regulatory factors of GPX4 may provide a theoretical basis for SIC treatment. In this study, a mouse SIC model revealed that elevated GDF15 exerts a protective effect. Antagonizing GDF15 exacerbates myocardial damage. Through transcriptomic analysis and other methods, we confirmed that GDF15 inhibits the expression of SOCS1 by activating the ALK5-SMAD2/3 pathway, thereby activates the JAK2/STAT3 pathway, promotes the transcription of GPX4, inhibits ferroptosis in cardiomyocytes, and plays a myocardial protective role in SIC.