Brain natriuretic peptide: A marker of myocardial dysfunction and prognosis during severe sepsis

Brain natriuretic peptide as a predictive marker of mortality in sepsis: an updated systematic review and meta-analysis

INTRODUCTION

Early identification of patients with sepsis at high risk of death remains a challenge, and whether brain natriuretic peptide (BNP) or N-terminal pro-B-type natriuretic peptide (NT-proBNP) has a prognostic effect on patients with sepsis is controversial. Here, we clarified the prognostic value of BNP and NT-proBNP and sought to establish suitable cutoff values and intervals.

METHODS

We searched five databases to identify studies that met the inclusion criteria. The primary outcomes were the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the curve (AUC), and corresponding 95% credible interval (95% CI) of BNP and NT-proBNP. The secondary outcomes were the sensitivity and specificity of BNP or NT-proBNP in subgroup analyses.

RESULTS

Forty-seven studies were included in our meta-analysis. The pooled sensitivity of NT-proBNP (0.77 [0.68, 0.84]) was weaker than that of BNP (0.82 [0.76, 0.87]), the pooled specificity of NT-proBNP (0.70 [0.60, 0.77]) was less than that of BNP (0.77 [0.71, 0.82]), and the AUC of BNP (0.87 [0.83-0.89]) was greater than that of NT-proBNP (0.80 (0.76-0.83]). The results of the subgroup analysis showed that the cutoff range of 400-800 pg/mL for BNP had high sensitivity (0.86 [0.74-0.98]) and specificity (0.87 [0.81-0.93]) and was probably the most appropriate cutoff range.

CONCLUSIONS

Elevated levels of BNP and NT-proBNP were significantly related to the mortality of patients with sepsis and had a moderate prognostic value in predicting the mortality of patients with sepsis. In addition, our meta-analysis preliminarily established appropriate cutoff values for BNP and NT-proBNP.

Screening of novel disease genes of sepsis-induced myocardial Disfunction by RNA sequencing and bioinformatics analysis

BACKGROUND

There is still a lack of effective treatment for sepsis-induced myocardial dysfunction (SIMD), while the pathogenesis of SIMD still remains largely unexplained.

METHODS

RNA sequencing results (GSE267388 and GSE79962) were used for cross-species integrative analysis. Bioinformatic analyses were used to delve into function, tissue- and cell- specificity, and interactions of genes. External datasets and qRT-PCR experiments were used for validation. L1000 FWD was used to predict targeted drugs, and 3D structure files were used for molecular docking.

RESULTS

Based on bioinformatic analyses, ten differentially expressed genes were selected as genes of interest, seven of which were verified to be significantly differential expression. Bucladesine was considered as a potential targeted drug for SIMD, which banded to seven target proteins primarily by forming hydrogen bonds.

CONCLUSION

It was considered that Cebpd, Timp1, Pnp, Osmr, Tgm2, Cp, and Asb2 were novel disease genes, while bucladesine was a potential therapeutic drug, of SIMD.

NOVEL ECHOCARDIOGRAM ANALYSIS OF CARDIAC DYSFUNCTION IS ASSOCIATED WITH MORTALITY IN PEDIATRIC SEPSIS

ABSTRACT

Objectives: The objective of our study was to semiautomatically generate echocardiogram indices in pediatric sepsis using novel algorithms and determine which indices were associated with mortality. We hypothesized that strain and diastolic indices would be most associated with mortality. Design: Retrospective cohort study of children with sepsis from 2017 to 2022. Survivors and nonsurvivors were compared for echocardiogram indices. Multivariate Cox proportional hazard models were constructed for our primary outcome of in-hospital mortality. Linear regression was performed for secondary outcomes, which included multiple composite 28-day outcomes. Results: Of the 54 patients in the study, 9 (17%) died. Multiple echocardiogram indices of both right (RV) and left ventricles (LV) were associated with in-hospital mortality [RV GLS adjusted hazard ratio (aHR): 1.16 (1.03-1.29), P = 0.011; RV global longitudinal early diastolic strain rate (GLSre) aHR: 0.24 (0.07 to 0.75), P = 0.014; LV GLSre aHR: 0.33 (0.11-0.97), P = 0.044]. Impairment in GLS was associated with fewer ventilator-free days [RV GLS β-coefficient: -0.47 (-0.84 to -0.10), P = 0.013; LV GLS β-coefficient -0.62 (-1.07 to -0.17), P = 0.008], organ-support free days [RV GLS β-coefficient: -0.49 (-0.87 to -0.11), P = 0.013; LV GLS β-coefficient: -0.64 (-1.10 to -0.17), P = 0.008], and days free from ICU [RV GLS β-coefficient: -0.42 (-0.79 to -0.05), P = 0.026; LV GLS β-coefficient: -0.58 (-1.03 to -0.13), P = 0.012]. Systolic indices were not associated with mortality in this cohort. Conclusion: Our study demonstrates the feasibility of obtaining echocardiogram indices in a semiautomatic method using our algorithms. We showed that abnormal strain is associated with worse outcomes in a cohort of children with sepsis.

Development and validation of a nomogram to predict risk of septic cardiomyopathy in the intensive care unit

The aim of this study was to develop a simple but effective nomogram to predict risk of septic cardiomyopathy (SCM) in the intensive care unit (ICU). We analyzed data from patients who were first admitted to the ICU for sepsis between 2008 and 2019 in the MIMIC-IV database, with no history of heart disease, and divided them into a training cohort and an internal validation cohort at a 7:3 ratio. SCM is defined as sepsis diagnosed in the absence of other cardiac diseases, with echocardiographic evidence of left (or right) ventricular systolic or diastolic dysfunction and a left ventricular ejection fraction (LVEF) of less than 50%. Variables were selected from the training cohort using the Least Absolute Shrinkage and Selection Operator (LASSO) regression to develop an early predictive model for septic cardiomyopathy. A nomogram was constructed using logistic regression analysis and its receiver operating characteristic (ROC) and calibration were evaluated in two cohorts. A total of 1562 patients participated in this study, with 1094 in the training cohort and 468 in the internal validation cohort. SCM occurred in 13.4% (147 individuals) in the training cohort, 16.0% (75 individuals) in the internal validation cohort. After adjusting for various confounding factors, we constructed a nomogram that includes SAPS II, Troponin T, CK-MB index, white blood cell count, and presence of atrial fibrillation. The area under the curve (AUC) for the training cohort was 0.804 (95% CI 0.764-0.844), and the Hosmer-Lemeshow test showed good calibration of the nomogram (P = 0.288). Our nomogram also exhibited good discriminative ability and calibration in the internal validation cohort. Our nomogram demonstrated good potential in identifying patients at increased risk of SCM in the ICU.

Procalcitonin, brain natriuretic peptide and albumin as markers to predict prognosis in hospitalized older Japanese patients with a risk of infection

AIM

Whether serum concentration of procalcitonin (PCT), brain natriuretic peptide (BNP) and albumin (Alb) have an association with the outcome of hospitalized older patients is unclear. We investigated clinical outcomes and any predictive factors in hospitalized Japanese older patients with a risk of infection.

METHODS

In the retrospective study, 820 Japanese patients were followed up for 30 days or until death. During the observation period, 656 patients survived and 164 patients died. The predictive factors of death were analyzed according to demographic and clinical variables.

RESULTS

The survival rate was decreased as the serum PCT increased from <0.5 to ≥10 ng/mL, as was also the case with BNP from <300 to ≥300 pg./mL, whereas low Alb (<2.5 g/dL) showed a lower survival rate than high Alb (≥2.5 g/dL; P < 0.01). Using the Cox regression model, the multivariable-adjusted hazard ratios (95% confidence interval) were as follows: PCT 0.5-2 versus <0.5 ng/mL: 1.61(1.04-2.49), PCT 2-10 versus <0.5 ng/mL: 1.91(1.15-3.16), PCT ≥10 versus <0.5 ng/mL: 2.90(1.84-4.59), high BNP 1.26 (0.89-1.76) and low Alb 0.68 (0.52-0.87). The mortality rate increased as the number of scores (PCT + BNP + Alb) increased.

CONCLUSIONS

Concentration-dependent high PCT, high BNP and low Alb were positive risk factors associated with poor prognosis in hospitalized older patients with a risk of infection. Geriatr Gerontol Int 2024; 24: 571-576.

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.

Meta-analysis of initial natriuretic peptides in the setting of sepsis-induced myocardial dysfunction

Aim: To investigate the association of initial brain natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) with the detection of sepsis-induced myocardial dysfunction (SIMD) in the setting of Sepsis 3.0. Methods: Three databases were searched to analyze initial BNP and NT-proBNP levels between SIMD and non-SIMD groups. Results: Eighteen studies were included, most of which defined SIMD based on echocardiography. The SIMD group exhibited higher initial BNP and NT-proBNP levels in blood. NT-proBNP higher than a certain cutoff value (>3000 pg/ml) was an independent risk factor for SIMD and its accuracy for SIMD diagnosis was moderate (pooled area under the curve: 0.81). Conclusion: Initial blood BNP and NT-proBNP levels are useful to assist in the detection of SIMD and further studies are warranted to determine the SIMD definition.

Sepsis induced cardiotoxicity by promoting cardiomyocyte cuproptosis

BACKGROUND

Currently, sepsis induced cardiotoxicity is among the major causes of sepsis-related death. The specific molecular mechanisms of sepsis induced cardiotoxicity are currently unknown. Therefore, the purpose of this paper is to identify the key molecule mechanisms for sepsis induced cardiotoxicity.

METHODS

Original data of sepsis induced cardiotoxicity was derived from Gene Expression Omnibus (GEO; GSE63920; GSE44363; GSE159309) dataset. Functional enrichment analysis was used to analysis sepsis induced cardiotoxicity related signaling pathways. Our findings also have explored the relationship of cuproptosis and N6-Methyladenosine (m6A) in sepsis induced cardiotoxicity. Mice are randomly assigned to 3 groups: saline treatment control group, LPS group administered a single 5 mg/kg dose of LPS for 24 h, LPS + CD274 inhibitor group administered 10 mg/kg CD274 inhibitor for 24 h.

RESULTS

Overall, expression of cuproptosis-related genes (CRGs) CD274, Ceruloplasmin (CP), Vascular endothelial growth factor A (VEGFA), Copper chaperone for cytochrome c oxidase 11 (COX11), chemokine C-C motif ligand 8 (CCL8), Mitogen-activated protein kinase kinase 1(MAP2K1), Amine oxidase 3 (AOC3) were significantly altered in sepsis induced cardiotoxicity. The results of spearman correlation analysis was significant relationship between differentially regulated genes (DEGs) of CRGs and the expression level of m6A methylation genes. GO and KEGG showed that these genes were enriched in response to interferon-beta, MHC class I peptide loading complex, proteasome core complex, chemokine receptor binding, TAP binding, chemokine activity, cytokine activity and many more. These findings suggest that cuproptosis is strongly associated with sepsis induced cardiotoxicity.

CONCLUSION

In the present study, we found that cuproptosis were associated with sepsis induced cardiotoxicity. The CD274, CP, VEGFA, COX11, CCL8, MAP2K1, AOC3 genes are showing a significant difference expression in sepsis induced cardiotoxicity. Our studies have found significant correlations between CRGs and m6A methylation related genes in sepsis induced cardiotoxicity. These results provide insight into mechanism for sepsis induced cardiotoxicity.

Seven-day and In-hospital Mortality According to Left and Right Ventricular Dysfunction in Patients With Septic Shock

BACKGROUND AND OBJECTIVES

The prognostic implications of septic cardiomyopathy have not been clearly demonstrated. We evaluated serial changes in left ventricular (LV) and right ventricular (RV) function in patients with septic shock and their prognostic value on 7-day and in-hospital mortality.

METHODS

Transthoracic echocardiography was performed within 48 hours of the diagnosis of septic shock and 7 days after the initial evaluation. In addition to traditional echocardiographic parameters, LV and RV function was evaluated using global longitudinal strain (GLS), and tricuspid annular plane systolic excursion (TAPSE).

RESULTS

A total of 162 patients (men, 83, 51.5%; 70.7±13.4 years; Acute Physiology and Chronic Health Evaluation [APACHE] II, 30.6±9.2) were enrolled. Initial GLS and TAPSE were -14.9±5.2% and 16.9±5.5 mm, and improved in the follow-up evaluation (GLS, -17.6±4.9%; TAPSE, 19.2±5.4 mm). Seven-day and in-hospital mortality were 24 (14.9%) and 64 (39.8%). Seven-day mortality was significantly associated with initial GLS >-16% (odds ratio [OR], 14.066, 95% confidence interval [CI], 1.178-167.969, p=0.037) and APACHE II score (OR, 1.196, 95% CI, 1.047-1.365, p=0.008). The in-hospital mortality of 7-day survivors was associated with follow-up TAPSE <16 mm (OR, 10.109, 95% CI, 1.640-62.322, p=0.013) and Sequential Organ Failure Assessment score (OR, 1.340, 95% CI, 1.078-1.667, p=0.008). GLS was not associated with in-hospital mortality of 7-day survivors.

CONCLUSIONS

Fluctuation of both ventricular function was common in septic shock. Seven-day mortality of patients with septic shock was related to GLS, whereas in-hospital mortality of 7-day survivors was related to TAPSE, not to GLS.

Research Progress on the Mechanism and Management of Septic Cardiomyopathy: A Comprehensive Review

Sepsis is defined as a kind of life-threatening organ dysfunction due to a dysregulated host immune response to infection and is a leading cause of mortality in the intensive care unit. Sepsis-induced myocardial dysfunction, also called septic cardiomyopathy, is a common and serious complication in patients with sepsis, which may indicate a bad prognosis. Although efforts have been made to uncover the pathophysiology of septic cardiomyopathy, a number of uncertainties remain. This article sought to review available literature to summarize the existing knowledge on current diagnostic tools and biomarkers, pathogenesis, and treatments for septic cardiomyopathy.

Role of toll-like receptor-mediated pyroptosis in sepsis-induced cardiomyopathy

Sepsis, a life-threatening dysregulated status of the host response to infection, can cause multiorgan dysfunction and mortality. Sepsis places a heavy burden on the cardiovascular system due to the pathological imbalance of hyperinflammation and immune suppression. Myocardial injury and cardiac dysfunction caused by the aberrant host responses to pathogens can lead to cardiomyopathy, one of the most critical complications of sepsis. However, many questions about the specific mechanisms and characteristics of this complication remain to be answered. The causes of sepsis-induced cardiac dysfunction include abnormal cardiac perfusion, myocardial inhibitory substances, autonomic dysfunction, mitochondrial dysfunction, and calcium homeostasis dysregulation. The fight between the host and pathogens acts as the trigger for sepsis-induced cardiomyopathy. Pyroptosis, a form of programmed cell death, plays a critical role in the progress of sepsis. Toll-like receptors (TLRs) act as pattern recognition receptors and participate in innate immune pathways that recognize damage-associated molecular patterns as well as pathogen-associated molecular patterns to mediate pyroptosis. Notably, pyroptosis is tightly associated with cardiac dysfunction in sepsis and septic shock. In line with these observations, induction of TLR-mediated pyroptosis may be a promising therapeutic approach to treat sepsis-induced cardiomyopathy. This review focuses on the potential roles of TLR-mediated pyroptosis in sepsis-induced cardiomyopathy, to shed light on this promising therapeutic approach, thus helping to prevent and control septic shock caused by cardiovascular disorders and improve the prognosis of sepsis patients.

Quantitative evaluation of myocardial layer-specific strain using two-dimensional speckle tracking echocardiography in septic patients

BACKGROUND

Although global longitudinal strain (GLS) is proven to be reduced and associated with adverse outcomes in septic patients, it has not been elucidated whether or not layer-specific strains are reduced. We aimed to explore the layer-specific strains of left ventricular (LV) for assessing myocardial dysfunction in septic patients.

METHODS

A prospective observational study of patients with sepsis was conducted in a tertiary hospital in China. Routine two-dimensional speckle tracking echocardiography was performed within 24 h of enrollment. Demographic data, laboratory values, and clinical outcomes were collected.

RESULTS

We recruited 79 septic patients finally. The mean age of septic patients was 59.4 years old and 45 (57.0%) were male. The median Acute Physiology Age and Chronic Health Evaluation (APACHE II) score, and mean sequential organ failure assessment (SOFA) score of all patients were 19.0 and 7.7, respectively. According to the left ventricular ejection fraction (LVEF) value of 50%, the patients were categorized into two groups: SICM (sepsis-induced cardiomyopathy, LVEF < 50%, n = 22) and non-SICM group ( LVEF ≥ 50%, n = 57). The median LVEF of SICM and non-SICM patients were 41.9% and 58.7%, and SICM patients had less negative layer-specific strain and global strain than that of non-SICM patients. The echocardiographic comparison of non-SICM and healthy controls was conducted to explore the myocardial injuries of non-SICM patients and the non-SICM had worse LS-epi than that of controls (-18.5% vs. -21.4%, p = 0.024).

CONCLUSION

There were 72.2% (57) septic patients presented with non-SICM (LVEF ≥ 50%), and the strain value of epicardium of them was less negative than healthy controls.

RIGHT VENTRICULAR DYSFUNCTION IN SEPSIS: AN UPDATED NARRATIVE REVIEW

ABSTRACT

Sepsis is a multisystem disease process, which constitutes a significant public health challenge and is associated with high morbidity and mortality. Among other systems, sepsis is known to affect the cardiovascular system, which may manifest as myocardial injury, arrhythmias, refractory shock, and/or septic cardiomyopathy. Septic cardiomyopathy is defined as the reversible systolic and/or diastolic dysfunction of one or both ventricles. Left ventricle dysfunction has been extensively studied in the past, and its prognostic role in patients with sepsis is well documented. However, there is relatively scarce literature on right ventricle (RV) dysfunction and its role. Given the importance of timely detection of septic cardiomyopathy and its bearing on prognosis of patients, the role of RV dysfunction has come into renewed focus. Hence, through this review, we sought to describe the pathophysiology of RV dysfunction in sepsis and what have we learnt so far about its multifactorial nature. We also elucidate the roles of different biomarkers for its detection and prognosis, along with appropriate management of such patient population.

Anti-inflammatory activity of carvacrol protects the heart from lipopolysaccharide-induced cardiac dysfunction by inhibiting pyroptosis via NLRP3/Caspase1/Gasdermin D signaling axis

AIMS

Lipopolysaccharide (LPS) is a well-known agent to induce septic conditions. Sepsis-induced cardiomyopathy has an overwhelming death rate. Carvacrol (CVL), a monoterpene phenol, has anti-inflammatory and antioxidant properties. The research aimed to investigate the effect of CVL on LPS-induced dysfunction in the heart. In this study, we evaluated the effect of CVL in LPS-stimulated H9c2 cardiomyoblast cells and Balb/c mice.

MAIN METHODS

LPS was used to induce septic conditions in H9c2 cardiomyoblast cells in vitro and in Balb/C mice. A survival study was conducted to assess the survival rate of mice after LPS and/or CVL treatment.

KEY FINDINGS

In vitro studies indicated that CVL inhibits reactive oxygen species (ROS) generation and abates pyroptosis mediated by NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome in H9c2 cells. In mice, CVL intervention improved the survival rate in septic conditions. The CVL administration markedly improved the echocardiographic parameters and alleviated the LPS-induced reduction in the ejection fraction (%) and fraction shortening (%). The CVL intervention restored the myocardial antioxidants and histopathological alterations and decreased the pro-inflammatory cytokine contents in the heart. Further findings disclosed that CVL reduced the protein levels of NLRP3, apoptosis-associated speck-like protein (ASC), caspase 1, interleukin (IL)-18, IL-1β, and the pyroptosis-indicative protein, gasdermin-D (GSDMD) in the heart. The autophagy-indicative proteins, beclin 1, and p62, in the heart were also restored in the CVL-treated group.

SIGNIFICANCE

Altogether, our findings demonstrated that CVL has a beneficial effect and can be a potential molecule against sepsis-induced myocardial dysfunction.

Is venoarterial extracorporeal membrane oxygenation an option for managing septic shock

PURPOSE OF REVIEW

To describe sepsis-induced cardiomyopathy. Discuss indications and current evidence of using venoarterial extracorporeal membrane oxygenation (VA-ECMO) in setting of sepsis-induced cardiomyopathy.

RECENT FINDINGS

Recent data suggests a survival benefit with the use of VA-ECMO in patients with septic shock complicated by septic-induced cardiomyopathy with severe left ventricular systolic dysfunction. VA-ECMO was associated with poor outcomes in adults with septic shock without severe systolic dysfunction. The evidence is generated from retrospective and meta-analysis of observational studies.

SUMMARY

Sepsis-induced cardiomyopathy is an increasingly recognized entity characterized by reversible ventricular dysfunction in the setting of sepsis. When hypotension persists despite standard management of septic shock (e.g. adequate fluid resuscitation, vasopressors, inotropes) and there is evidence of severe cardiac systolic dysfunction and end-organ hypoperfusion, VA-ECMO should be considered as a bridge therapy to recovery. VA-ECMO should not be used for isolated vasodilatory septic shock without significant myocardial dysfunction.

A bibliometric analysis of sepsis-induced myocardial dysfunction from 2002 to 2022

Background

Sepsis-induced myocardial dysfunction (SIMD) has a significant contribution to sepsis-caused death in critically ill patients. In recent years, the number of published articles related to SIMD has increased rapidly. However, there was no literature that systematically analyzed and evaluated these documents. Thus, we aimed to lay a foundation for researchers to quickly understand the research hotspots, evolution processes and development trends in the SIMD field via a bibliometric analysis.

Methods

Articles related to SIMD were retrieved and extracted from the Web of Science Core Collection on July 19th, 2022. CiteSpace (version 6.1.R2) and VOSviewer (version 1.6.18) were used for performing visual analysis.

Results

A total of 1,076 articles were included. The number of SIMD-related articles published each year has increased significantly. These publications mainly came from 56 countries, led by China and the USA, and 461 institutions, but without stable and close cooperation. As authors, Li Chuanfu published the most articles, while Rudiger Alain had the most co-citations. Shock was the journal with the most studies, and Critical Care Medicine was the most commonly cited journal. All keywords were grouped into six clusters, some of which represented the current and developing research directions of SIMD as the molecular mechanisms.

Conclusion

Research on SIMD is flourishing. It is necessary to strengthen cooperation and exchanges between countries and institutions. The molecular mechanisms of SIMD, especially oxidative stress and regulated cell death, will be critical subjects in the future.

Untargeted metabolomic profiling of sepsis-induced cardiac dysfunction

OBJECTIVE

Sepsis is a life-threatening condition secondary to infection that evolves into a dysregulated host response and is associated with acute organ dysfunction. Sepsis-induced cardiac dysfunction is one of the most complex organ failures to characterize. This study performed comprehensive metabolomic profiling that distinguished between septic patients with and without cardiac dysfunction.

METHOD

Plasma samples collected from 80 septic patients were analysed by untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics. Principal component analysis (PCA), partial least squares discrimination analysis (PLS-DA), and orthogonal partial least square discriminant analysis (OPLS-DA) were applied to analyse the metabolic model between septic patients with and without cardiac dysfunction. The screening criteria for potential candidate metabolites were as follows: variable importance in the projection (VIP) >1, P < 0.05, and fold change (FC) > 1.5 or < 0.7. Pathway enrichment analysis further revealed associated metabolic pathways. In addition, we constructed a subgroup metabolic analysis between the survivors and non-survivors according to 28-day mortality in the cardiac dysfunction group.

RESULTS

Two metabolite markers, kynurenic acid and gluconolactone, could distinguish the cardiac dysfunction group from the normal cardiac function group. Two metabolites, kynurenic acid and galactitol, could distinguish survivors and non-survivors in the subgroup analysis. Kynurenic acid is a common differential metabolite that could be used as a candidate for both diagnosis and prognosis for septic patients with cardiac dysfunction. The main associated pathways were amino acid metabolism, glucose metabolism and bile acid metabolism.

CONCLUSION

Metabolomic technology could be a promising approach for identifying diagnostic and prognostic biomarkers of sepsis-induced cardiac dysfunction.

Vitamin C alleviates LPS-induced myocardial injury by inhibiting pyroptosis via the ROS-AKT/mTOR signalling pathway

BACKGROUND

The efficacy of vitamin C in sepsis remains controversial. Whether vitamin C can alleviate lipopolysaccharide (LPS)-induced myocardial injury by inhibiting pyroptosis has not been studied. This study aimed to evaluate the effects of vitamin C on LPS-induced myocardial injury in vitro.

METHODS

H9C2 cells were treated with indicated concentrations of LPS, and the cell viability was then assessed by CCK-8 assay. The levels of lactate dehydrogenase (LDH), CK-MB, IL-18 and IL-1β were examined by enzyme-linked immunosorbent assay (ELISA). The levels of intracellular reactive oxygen species (ROS) were measured using the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA). Western blot assays were conducted to determine the levels of the ROS-associated protein nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4) and pyroptosis-associated proteins, such as NOD-like receptor (NLR) family pyrin domain containing 3 (NLRP3), caspase-1 and gasdermin D (GSDMD). The AKT inhibitor MK-2206 was then applied to explore the signalling pathway. Finally, H9C2 cells were divided into the control group, LPS group, vitamin C + LPS group, and N-acetyl-L-cysteine (NAC) + LPS group. The intracellular ROS, levels of associated proteins, cell viability, and release of LDH, CK-MB, IL-18 and IL-1β were examined.

RESULTS

LPS decreased cell viability and induced ROS and pyroptosis in H9C2 cells in a dose-dependent manner. Moreover, LPS activated the AKT/mTOR pathway in H9C2 cells. The AKT inhibitor MK-2206 protected H9C2 cells from LPS-induced death by suppressing pyroptosis, without changing intracellular ROS level. Vitamin C significantly inhibited intracellular ROS and cell pyroptosis in LPS-treated H9C2 cells. Moreover, vitamin C suppressed the activation of the AKT/mTOR pathway.

CONCLUSIONS

Our data suggest that vitamin C alleviates LPS-induced myocardial injury by inhibiting pyroptosis via the ROS-AKT/mTOR signalling pathway and thus provide novel insights into the prevention of sepsis-induced myocardial dysfunction.

Association of sepsis-induced cardiomyopathy and mortality: a systematic review and meta-analysis

BACKGROUND

The implication of sepsis-induced cardiomyopathy (SIC) to prognosis is controversial, and its association with mortality at different stages remains unclear. We conducted a systematic review and meta-analysis to understand the association between SIC and mortality in septic patients.

METHODS

We searched and appraised observational studies regarding the mortality related to SIC among septic patients in PubMed and Embase from inception until 8 July 2021. Outcomes comprised in-hospital and 1-month mortality. We adopted the random-effects model to examine the mortality risk ratio in patients with and without SIC. Meta-regression, subgroup, and sensitivity analyses were applied to examine the outcome's heterogeneity.

RESULTS

Our results, including 20 studies and 4,410 septic patients, demonstrated that SIC was non-statistically associated with increased in-hospital mortality, compared to non-SIC (RR 1.28, [0.96-1.71]; p = 0.09), but the association was statistically significant in patients with the hospital stay lengths longer than 10 days (RR 1.40, [1.02-1.93]; p = 0.04). Besides, SIC was significantly associated with a higher risk of 1-month mortality (RR 1.47, [1.17-1.86]; p < 0.01). Among SIC patients, right ventricular dysfunction was significantly associated with increased 1-month mortality (RR 1.72, [1.27-2.34]; p < 0.01), while left ventricular dysfunction was not (RR 1.33, [0.87-2.02]; p = 0.18).

CONCLUSIONS

With higher in-hospital mortality in those hospitalized longer than 10 days and 1-month mortality, our findings imply that SIC might continue influencing the host's system even after recovery from cardiomyopathy. Besides, right ventricular dysfunction might play a crucial role in SIC-related mortality, and timely biventricular assessment is vital in managing septic patients.

Cardiac Troponin I Reveals Diagnostic and Prognostic Superiority to Aminoterminal Pro-B-Type Natriuretic Peptide in Sepsis and Septic Shock

Data regarding the prognostic value of cardiac biomarkers in patients suffering from sepsis or septic shock is scarce. Studies investigating the prognostic role of cardiac biomarkers in patients with sepsis and septic shock were commonly published prior to the sepsis-3 criteria and were often not restricted to septic patients only, too. This study investigated the diagnostic and prognostic value of the aminoterminal pro-B-type Natriuretic Peptide (NT-pro BNP) and cardiac troponin I (cTNI) in patients with sepsis and septic shock. Consecutive patients with sepsis and septic shock were included from 2019 to 2021. Blood samples were retrieved from the day of disease onset (i.e., day 1), day 2 and 3. Firstly, the diagnostic value of the NT-pro BNP and cTNI to diagnose sepsis or septic shock was tested. Secondly, the prognostic value of the NT-pro BNP and cTNI was examined with regard to the 30-day all-cause mortality. The statistical analyses included univariable t-tests, Spearman’s correlations, C-statistics, Kaplan–Meier analyses and Cox proportional regression analyses. A total of 162 patients were included prospectively, of which 57% had a sepsis and 43% a septic shock. The overall rate of all-cause mortality at 30 days was 53%. With an area under the curve (AUC) of 0.658 on day 1 and 0.885 on day 3, cTNI expressed a better diagnostic value than NT-pro BNP, especially on day 3 (ΔAUCd3 = 0.404; p = 0.022). Furthermore, cTNI displayed a moderate but slightly better prognostic value than NT-pro BNP on all examined days (AUC for cTNI, d1 = 0.635; 95% CI 0.541–0.729; p = 0.007 vs. AUC for NT-pro BNP, d1 = 0.582; 95% CI 0.477–0.687; p = 0.132). In conclusion, cTNI was a reliable diagnostic parameter for the diagnosis of sepsis and septic shock, as well as a reliable prognostic tool with regard to 30-day all-cause mortality in patients suffering from sepsis and septic shock.

Recombinant thrombomodulin may protect cardiac capillary endothelial glycocalyx through promoting Glypican-1 expression under experimental endotoxemia

Introduction

Myocardial dysfunction occurs in patients with sepsis due to vascular endothelial injury. Recombinant human thrombomodulin (rhTM) attenuates vascular endothelial injuries through endothelial glycocalyx (eGC) protection.

Hypothesis

We hypothesized that rhTM attenuates myocardial dysfunction via the inhibition of vascular endothelial injury during sepsis.

Methods

Ten-week-old male C57BL6 mice were injected intraperitoneally with 20 mg/kg of lipopolysaccharide (LPS). In rhTM-treated mice, rhTM was injected intraperitoneally at 3 and 24 h after LPS injection. Saline was injected intraperitoneally as control. To assess for eGC injury, intensity score was measured 48 h after the LPS injection. To confirm vascular endothelial injuries, ultrastructural analysis was performed using scanning (SEM) and transmission electron microscopy (TEM).

Results

The survival rate of the rhTM group at 48 h after LPS injection was significantly higher than that of the control group (68% vs. 17%, p < 0.05). The serum level of troponin I in the rhTM group was lower than that in the control (2.2 ± 0.4 ng/dL vs 9.4 ± 1.1 ng/dL, p < 0.05). The expression of interleukin-6 (IL-6) was attenuated in the rhTM-treated group than in the control (65.3 ± 15.3 ng/mL vs 226.3 ± 19.4 ng/mL, p < 0.05). The serum concentration of syndecan-1, a marker of glycocalyx damage, was significantly decreased 48 h post-administration of LPS in the rhTM-treated group than in the control group. In ultrastructural analysis using SEM and TEM, eGC peeled off from the surface of the capillary lumen in the control. Conversely, the eGC injury was attenuated in the rhTM group. Gene set enrichment analysis revealed that osteomodulin, osteoglycin proline/arginine-rich end leucine-rich repeat protein, and glypican-1, which are proteoglycans, were preserved by rhTM treatment. Their protein expression was retained in endothelial cells.

Conclusion

rhTM attenuates sepsis-induced myocardial dysfunction via eGC protection.

Identification of immune-related hub genes and miRNA-mRNA pairs involved in immune infiltration in human septic cardiomyopathy by bioinformatics analysis

Abstract

Septic cardiomyopathy (SCM) is a serious complication caused by sepsis that will further exacerbate the patient's prognosis. However, immune-related genes (IRGs) and their molecular mechanism during septic cardiomyopathy are largely unknown. Therefore, our study aims to explore the immune-related hub genes (IRHGs) and immune-related miRNA-mRNA pairs with potential biological regulation in SCM by means of bioinformatics analysis and experimental validation.

Method

Firstly, screen differentially expressed mRNAs (DE-mRNAs) from the dataset GSE79962, and construct a PPI network of DE-mRNAs. Secondly, the hub genes of SCM were identified from the PPI network and the hub genes were overlapped with immune cell marker genes (ICMGs) to further obtain IRHGs in SCM. In addition, receiver operating characteristic (ROC) curve analysis was also performed in this process to determine the disease diagnostic capability of IRHGs. Finally, the crucial miRNA-IRHG regulatory network of IRHGs was predicted and constructed by bioinformatic methods. Real-time quantitative reverse transcription-PCR (qRT-PCR) and dataset GSE72380 were used to validate the expression of the key miRNA-IRHG axis.

Result

The results of immune infiltration showed that neutrophils, Th17 cells, Tfh cells, and central memory cells in SCM had more infiltration than the control group; A total of 2 IRHGs were obtained by crossing the hub gene with the ICMGs, and the IRHGs were validated by dataset and qRT-PCR. Ultimately, we obtained the IRHG in SCM: THBS1. The ROC curve results of THBS1 showed that the area under the curve (AUC) was 0.909. Finally, the miR-222-3p/THBS1 axis regulatory network was constructed.

Conclusion

In summary, we propose that THBS1 may be a key IRHG, and can serve as a biomarker for the diagnosis of SCM; in addition, the immune-related regulatory network miR-222-3p/THBS1 may be involved in the regulation of the pathogenesis of SCM and may serve as a promising candidate for SCM therapy.

N-Terminal B Natriuretic Peptide as a Prognostic Marker in Sepsis Induced Myocardial Dysfunction

BACKGROUND: Sepsis-induced myocardial dysfunction (SIMD) is an increasingly recognized form of transient cardiac dysfunction in sepsis patients. AIM: The aim of the study was to evaluation of N-terminal pro brain natriuretic peptide (NT-pro BNP) as a predictor of SIMD and poor outcome in patients with sepsis or septic shock. METHODS: Forty patients were enrolled and divided into: Group 1 with sepsis; Group 2 with septic shock. Each group was subdivided according to the presence or absence of cardiomyopathy. Echocardiography, NT-pro BNP - assay on the 1st and 2nd days of admission - were performed. RESULTS: NT-pro BNP level was significant predictor for cardiomyopathy in all case group with 75% sensitivity, 70% specificity (cutoff level >334 pg/ml) on 1st day of admission and 65% sensitivity, and 80% specificity (cutoff level >325 pg/ml) on 2nd day. On subgroup analysis, pro-BNP had 70% sensitivity, 90% specificity; cutoff level >334 pg/ml for prediction of cardiomyopathy in sepsis group and 70% sensitivity and 80% specificity; cutoff level >357pg/ml in septic shock group. Pro-BNP on 2nd day was excellent predictor of mortality in septic shock group with 100% sensitivity and specificity; cutoff level >350 pg/ml. CONCLUSION: N terminal pro-BNP is a good diagnostic and prognostic indicator for cardiomyopathy and mortality in septic patients.

Sepsis and the Heart: More to Learn

How to cite this article: Samavedam S. Sepsis and the Heart: More to Learn. Indian J Crit Care Med 2022;26(7):775-777.

Identification and Validation of Immune-Related Biomarker Gene and Construction of ceRNA Networks in Septic Cardiomyopathy

Septic cardiomyopathy (SCM) is a cardiac dysfunction caused by severe sepsis, which greatly increases the risk of heart failure and death, and its molecular mechanism is unclear. The immune response has been reported to be an important process in septic cardiomyopathy and is present in the cardiac tissue of patients with sepsis, suggesting that the immune response may be an underlying mechanism of myocardial injury in SCM. Therefore, we explored the role of immune-related genes (IRGs) in SCM and aimed to identify pivotal immune-related targets with the aim of identifying key immune-related targets in SCM and potential therapeutic mechanisms involved in the pathological process of SCM. To explore the regulatory mechanisms of immune responses in SCM, we identified differentially expressed genes (DEGs) shared in the SCM datasets GSE179554 and GSE40180 by bioinformatics analysis and then obtained hub genes from the DEGs. Then, we obtained the immune-related hub genes (IRHGs) by intersecting the hub genes with IRGs and performed quantitative reverse transcription polymerase chain reaction to confirm the abnormal expression of IRHGs. Finally, we further constructed an immune-related lncRNA–miRNA–IRHG ceRNA regulatory network. In this study, we identified an IRHG that may be involved in the pathogenesis of SCM, which helps us to further elucidate the role of immune response in SCM and gain insights into the molecular mechanisms and potential therapeutic targets of SCM.

Construction of a predictive model and prognosis of left ventricular systolic dysfunction in patients with sepsis based on the diagnosis using left ventricular global longitudinal strain

BACKGROUND

Cardiac dysfunction, a common complication of sepsis, is associated with increased mortality. However, its risk factors are poorly understood, and a predictive model might help in the management of cardiac dysfunction.

METHODS

A monocentric prospective study of patients with sepsis was performed. Left ventricular global longitudinal strain (LV GLS) was measured using echocardiography within 72 h of the patients diagnosed with sepsis, and the patients were categorized into two groups: LV GLS > -17%, left ventricular systolic dysfunction group (LVSD group); and LV GLS ≤ -17%, non-left ventricular systolic dysfunction group (Non-LVSD group). The baseline characteristics and prognosis of the two groups were analyzed. Based on the results of the multivariate logistic regression analysis, a predictive model of LVSD was established and a nomogram was drawn.

RESULTS

Fifty-one left ventricular systolic dysfunction in patients with sepsis and 73 non-LVSD sepsis patients were included. Prognostic analysis showed that patients with LVSD had higher ICU mortality, in-hospital mortality, the incidence of atrial fibrillation (P < 0.05), and risk of death (HR = 3.104, 95% CI = 1.617-5.957, P < 0.001) compared to patients with non-LVSD. There were no significant differences in the rate of tracheal intubation, the incidence of acute kidney injury (AKI), the proportion of continuous renal replacement therapy (CRRT), length of ICU stay, and length of hospital stay between the 2 groups (P > 0.05). High sensitive troponin I (Hs-TnI) ≥ 0.131 ng/ml, procalcitonin (PCT) ≥ 40 ng/ml, lactate (Lac) ≥ 4.2 mmol/L, and N-terminal pro-brain natriuretic peptide (NT-proBNP) ≥ 3270 pg/ml were found to be the best cut-off values for the prediction of LVSD.

CONCLUSION

Sepsis patients with left ventricular systolic dysfunction had a higher risk of death and atrial fibrillation. Hs-TnI, PCT, Lac, and NT-proBNP were independent risk factors of LVSD, and the LVSD predictive model constructed using these factors showed good diagnostic performance.

TRIAL REGISTRATION

Chinese Clinical Trial Registry No: ChiCTR2000032128. Registered on 20 April 2020, http://www.chictr.org.cn/showproj.aspx ?proj=52531.

Fusion of fully integrated analog machine learning classifier with electronic medical records for real-time prediction of sepsis onset

The objective of this work is to develop a fusion artificial intelligence (AI) model that combines patient electronic medical record (EMR) and physiological sensor data to accurately predict early risk of sepsis. The fusion AI model has two components—an on-chip AI model that continuously analyzes patient electrocardiogram (ECG) data and a cloud AI model that combines EMR and prediction scores from on-chip AI model to predict fusion sepsis onset score. The on-chip AI model is designed using analog circuits for sepsis prediction with high energy efficiency for integration with resource constrained wearable device. Combination of EMR and sensor physiological data improves prediction performance compared to EMR or physiological data alone, and the late fusion model has an accuracy of 93% in predicting sepsis 4 h before onset. The key differentiation of this work over existing sepsis prediction literature is the use of single modality patient vital (ECG) and simple demographic information, instead of comprehensive laboratory test results and multiple vital signs. Such simple configuration and high accuracy makes our solution favorable for real-time, at-home use for self-monitoring.

Impact of Pulmonary Arterial Hypertension on Systemic Inflammation, Cardiac Injury and Hemodynamics in Sepsis: A retrospective study from MIMIC-III

BACKGROUND

Sepsis and pulmonary arterial hypertension (PAH) may both present in a single patient in the intensive care unit. The impact of PAH on the sepsis process is not well understood. Here we assess the effect of PAH in patients with sepsis from multiple perspectives.

METHODS

Patients with sepsis with or without PAH underwent propensity score matching according to age, sex and ethnicity. Clinical complications, hemodynamics, and laboratory examinations, including heart injury and inflammation, were compared between the 2 groups. We aimed to model the relationship between the severity of PAH and systemic inflammation levels using linear regression analysis. Factors associated with 28-day and one-year mortality in patients with sepsis with PAH were also analyzed using binary logistic regression.

RESULTS

A total of 285 pairs of patients with sepsis with or without PAH were included in the analysis. There were no significant differences in the C-reactive protein (CRP), white blood cell (WBC), or lactate levels or neutrophil percentage between the 2 groups, and the mean pulmonary arterial pressure and N-terminal pro b-type natriuretic peptide (NTproBNP) level did not correlate with CRP, WBC or lactate. The cardiac injury indexes were significantly higher in the PAH group. Lower mean arterial pressure was found in patients with PAH. Longer ventilation duration was a risk factor for, while obesity was protective against, both short- and long-term mortality in patients with sepsis with PAH.

CONCLUSIONS

PAH had little effect on the inflammation profile in sepsis, but it may worsen the sepsis outcome by impairing cardiac function and subsequent hemodynamic stability.

Comparison of Troponin I levels versus myocardial dysfunction on prognosis in sepsis

In the context of sepsis, we tested the relationship between echocardiographic findings and Troponin, and their impact on prognosis. In this prospective study, we enrolled 325 septic patients (41% with shock), not mechanically ventilated, between October, 2012 and June, 2019 among those admitted to our High-Dependency Unit. By echocardiography within 24 h from the admission, sepsis-induced myocardial dysfunction (SIMD) was defined as left ventricular (LV) systolic dysfunction (speckle-tracking-based global longitudinal peak systolic strain, GLS, >  - 14%) and/or right ventricular (RV) systolic dysfunction (Tricuspid Annular Plane Systolic Excursion, TAPSE < 16 mm). Troponin I levels were measured upon admission (T0) and after 24 h (T1); it was considered normal if > 0.1 ng/mL. Mortality was assessed at day-7 and day-28 end-points. One-hundred and forty-two patients had normal Troponin level at T0 and T1 (G1), 69 had abnormal levels at T0 or T1 (G2) and 114 showed abnormal Troponin levels at both T0 and T1 (G3). Compared to G1, patients in G3 had worse LV and RV systolic function (GLS  - 11.6 ± 3.4% vs  - 14.0 ± 3.5%, p < 0.001; TAPSE 18 ± 0.5 vs 19 ± 0.5 mm, p = 0.047) and greater day-28 (34% vs 20%, p = 0.015) mortality. In a Cox survival analysis including age, Troponin and SOFA score, mortality was predicted by the presence of SIMD (RR 3.24, 95% CI 1.72-6.11, p < 0.001) with no contribution of abnormal Troponin level. While abnormal Troponin levels were associated with SIMD diagnosed by echocardiography, only the presence of SIMD predicted the short- and medium-term mortality rate, without an independent contribution of increased Troponin levels.

Cardiac Metabolism in Sepsis

The mechanism of sepsis-induced cardiac dysfunction is believed to be different from that of myocardial ischemia. In sepsis, chemical mediators, such as endotoxins, cytokines, and nitric oxide, cause metabolic abnormalities, mitochondrial dysfunction, and downregulation of β-adrenergic receptors. These factors inhibit the production of ATP, essential for myocardial energy metabolism, resulting in cardiac dysfunction. This review focuses on the metabolic changes in sepsis, particularly in the heart. In addition to managing inflammation, interventions focusing on metabolism may be a new therapeutic strategy for cardiac dysfunction due to sepsis.

Inhibition of the NLRP3/IL-1β axis protects against sepsis-induced cardiomyopathy

BACKGROUND

Septic cardiomyopathy worsens the prognosis of critically ill patients. Clinical data suggest that interleukin-1β (IL-1β), activated by the NLRP3 inflammasome, compromises cardiac function. Whether or not deleting Nlrp3 would prevent cardiac atrophy and improve diastolic cardiac function in sepsis was unclear. Here, we investigated the role of NLRP3/IL-1β in sepsis-induced cardiomyopathy and cardiac atrophy.

METHODS

Male Nlrp3 knockout (KO) and wild-type (WT) mice were exposed to polymicrobial sepsis by caecal ligation and puncture (CLP) surgery (KO, n = 27; WT, n = 33) to induce septic cardiomyopathy. Sham-treated mice served as controls (KO, n = 11; WT, n = 16). Heart weights and morphology, echocardiography and analyses of gene and protein expression were used to evaluate septic cardiomyopathy and cardiac atrophy. IL-1β effects on primary and immortalized cardiomyocytes were investigated by morphological and molecular analyses. IonOptix and real-time deformability cytometry (RT-DC) analysis were used to investigate functional and mechanical effects of IL-1β on cardiomyocytes.

RESULTS

Heart morphology and echocardiography revealed preserved systolic (stroke volume: WT sham vs. WT CLP: 33.1 ± 7.2 μL vs. 24.6 ± 8.7 μL, P < 0.05; KO sham vs. KO CLP: 28.3 ± 8.1 μL vs. 29.9 ± 9.9 μL, n.s.; P < 0.05 vs. WT CLP) and diastolic (peak E wave velocity: WT sham vs. WT CLP: 750 ± 132 vs. 522 ± 200 mm/s, P < 0.001; KO sham vs. KO CLP: 709 ± 152 vs. 639 ± 165 mm/s, n.s.; P < 0.05 vs. WT CLP) cardiac function and attenuated cardiac (heart weight-tibia length ratio: WT CLP vs. WT sham: -26.6%, P < 0.05; KO CLP vs. KO sham: -3.3%, n.s.; P < 0.05 vs. WT CLP) and cardiomyocyte atrophy in KO mice during sepsis. IonOptix measurements showed that IL-1β decreased contractility (cell shortening: IL-1β: -15.4 ± 2.3%, P < 0.001 vs. vehicle, IL-1RA: -6.1 ± 3.3%, P < 0.05 vs. IL-1β) and relaxation of adult rat ventricular cardiomyocytes (time-to-50% relengthening: IL-1β: 2071 ± 225 ms, P < 0.001 vs. vehicle, IL-1RA: 564 ± 247 ms, P < 0.001 vs. IL-1β), which was attenuated by an IL-1 receptor antagonist (IL-1RA). RT-DC analysis indicated that IL-1β reduced cardiomyocyte size (P < 0.001) and deformation (P < 0.05). RNA sequencing showed that genes involved in NF-κB signalling, autophagy and lysosomal protein degradation were enriched in hearts of septic WT but not in septic KO mice. Western blotting and qPCR disclosed that IL-1β activated NF-κB and its target genes, caused atrophy and decreased myosin protein in myocytes, which was accompanied by an increased autophagy gene expression. These effects were attenuated by IL-1RA.

CONCLUSIONS

IL-1β causes atrophy, impairs contractility and relaxation and decreases deformation of cardiomyocytes. Because NLRP3/IL-1β pathway inhibition attenuates cardiac atrophy and cardiomyopathy in sepsis, it could be useful to prevent septic cardiomyopathy.

GSDMD Mediates LPS-Induced Septic Myocardial Dysfunction by Regulating ROS-dependent NLRP3 Inflammasome Activation

Myocardial dysfunction is a serious consequence of sepsis and contributes to high mortality. Currently, the molecular mechanism of myocardial dysfunction induced by sepsis remains unclear. In the present study, we investigated the role of gasdermin D (GSDMD) in cardiac dysfunction in septic mice and the underlying mechanism. C57BL/6 wild-type (WT) mice and age-matched Gsdmd-knockout (Gsdmd ^-/-) mice were intraperitoneally injected with lipopolysaccharide (LPS) (10 mg/kg) to mimic sepsis. The results showed that GSDMD-NT, the functional fragment of GSDMD, was upregulated in the heart tissue of septic WT mice induced by LPS, which was accompanied by decreased cardiac function and myocardial injury, as shown by decreased ejection fraction (EF) and fractional shortening (FS) and increased cardiac troponin I (cTnI), creatine kinase isoenzymes MB (CK-MB), and lactate dehydrogenase (LDH). Gsdmd ^-/- mice exhibited protection against LPS-induced myocardial dysfunction and had a higher survival rate. Gsdmd deficiency attenuated LPS-induced myocardial injury and cell death. Gsdmd deficiency prevented LPS-induced the increase of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in serum, as well as IL-1β and TNF-α mRNA levels in myocardium. In addition, LPS-mediated inflammatory cell infiltration into the myocardium was ameliorated and activation of NF-κB signaling pathway and the NOD-like receptor protein 3 (NLPR3) inflammasome were suppressed in Gsdmd ^-/- mice. Further research showed that in the myocardium of LPS-induced septic mice, GSDMD-NT enrichment in mitochondria led to mitochondrial dysfunction and reactive oxygen species (ROS) overproduction, which further regulated the activation of the NLRP3 inflammasome. In summary, our data suggest that GSDMD plays a vital role in the pathophysiology of LPS-induced myocardial dysfunction and may be a crucial target for the prevention and treatment of sepsis-induced myocardial dysfunction.

Incidence, prognosis, and risk factors of sepsis-induced cardiomyopathy

BACKGROUND

At present, large-scale studies on the clinical characteristics of sepsis-induced cardiomyopathy (SIC) are lacking.

AIM

To investigate the clinical characteristics of SIC.

METHODS

Based on the analysis of the MIMIC-III public database, we performed a large-scale retrospective study involving sepsis patients who were admitted to the intensive care unit (ICU) and had no concomitant cardiac disease. We used propensity score matching analysis and multivariate logistic regression to ensure the robustness of the results. The primary outcome was hospital mortality, and the secondary outcomes included the number of patients who received mechanical ventilation or renal replacement therapy during their hospital stay, the number of patients administered with vasopressors, the length of ICU stay, and the length of hospital stay.

RESULTS

In the present study, after screening 38605 patients, 3530 patients with sepsis were included. A total of 997 patients met the SIC diagnostic criteria, and the incidence of SIC was 28.20% (95% confidence interval [CI]: 26.80%-29.70%). Compared to patients in the non-SIC group, patients in the SIC group were of older age and had a higher Simplified Acute Physiology Score (SAPS)-I score, SAPS-II score, and Elixhauser comorbidity index (ECI). A total of 367 (36.8%) of 997 patients in the SIC group and 818 (32.3%) of 2533 patients in the non-SIC group died in the hospital, which resulted in a significant between-group difference (odds ratios = 1.22, 95%CI: 1.05-1.42; P = 0.011). For the secondary outcomes, more patients in the SIC group received mechanical ventilation and vasopressors. Multivariate logistic regression analysis showed that age, male sex, ECI, hemoglobin level, diabetes, and mechanical ventilation use on the first day of ICU admission were risk factors for SIC.

CONCLUSION

Compared with non-SIC patients, hospital mortality is higher in SIC patients.

Paeoniflorin improves myocardial injury via p38 MAPK/NF-KB p65 inhibition in lipopolysaccharide-induced mouse

Background

Paeoniflorin (Pae) is an active compound with a variety of pharmacological effects. This aim was to investigate how Pae protects against myocardial injury and to explore its potential mechanism.

Methods

We established a BALB/c mouse model that was intraperitoneal injection (i.p.) of RvE1 (25 µg/kg) or Pae (20 mg/kg) for 3 days, and then treated with lipopolysaccharide (LPS, 10 mg/kg, i.p.). The mice were randomly divided into the sham group, the LPS group, the LPS + RvE1 group, the LPS + Pae group (n=8). Cardiac dysfunction was detected by HE staining and ELISA assay. The oxidative stress, mitochondrial membrane potential (MMP), mitochondrial permeability transition pore (mPTP) and apoptosis were assessed. Furthermore, western blotting (WB) assay were employed to analyze the protective mechanisms.

Results

Pae improved LPS-induced cardiac function and impeded apoptosis. Pae significantly reduced the release of inflammatory cytokines such as interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and IL-1β. Furthermore, Pae decreased malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS), and increased superoxide dismutase (SOD). In addition, Pae attenuated the mPTP opening and MMP depolarization. Notably, Pae treatment inhibited the activation of p38 MAPK and NF-κB p65.

Conclusions

It was confirmed that Pae alleviated LPS-induced myocardial injury. Pae might be as a new drug candidate for myocardial ischaemic complications.

Melatonin Alleviates Cardiac Function in Sepsis-Caused Myocarditis via Maintenance of Mitochondrial Function

Melatonin (N-acetyl-5-methoxytryptamine) has been shown to have a cardioprotective effect against myocarditis. However, the mechanisms underlying the protective role of melatonin (MLT) in sepsis-induced myocarditis are yet to be revealed. In this study, MLT was administrated to mice, 14 days before cecal ligation puncture surgery. Echocardiography results showed that MLT alleviated cardiac dysfunction in sepsis-induced myocarditis. Furthermore, MLT reduced cardiac inflammation by inhibiting the expression of Il-1α, Il-1β, Il-6, and Mcp-1 messenger RNA (mRNA) levels. The RNA sequencing (RNA-seq) assays with heart tissues showed that MLT maintains the mitochondrial function in sepsis-caused myocarditis. Additionally, the production of reactive oxygen species (ROS) in heart tissues was suppressed by MLT. Taken together, in evaluating the therapeutic effect of MLT on sepsis-induced myocarditis, the results showed that MLT alleviated cardiac damage by regulating mitochondrial function and mitochondrial ROS.

Deep-learning model for screening sepsis using electrocardiography

Background

Sepsis is a life-threatening organ dysfunction and a major healthcare burden worldwide. Although sepsis is a medical emergency that requires immediate management, screening for the occurrence of sepsis is difficult. Herein, we propose a deep learning-based model (DLM) for screening sepsis using electrocardiography (ECG).

Methods

This retrospective cohort study included 46,017 patients who were admitted to two hospitals. A total of 1,548 and 639 patients had sepsis and septic shock, respectively. The DLM was developed using 73,727 ECGs from 18,142 patients, and internal validation was conducted using 7774 ECGs from 7,774 patients. Furthermore, we conducted an external validation with 20,101 ECGs from 20,101 patients from another hospital to verify the applicability of the DLM across centers.

Results

During the internal and external validations, the area under the receiver operating characteristic curve (AUC) of the DLM using 12-lead ECG was 0.901 (95% confidence interval, 0.882–0.920) and 0.863 (0.846–0.879), respectively, for screening sepsis and 0.906 (95% confidence interval (CI), 0.877–0.936) and 0.899 (95% CI, 0.872–0.925), respectively, for detecting septic shock. The AUC of the DLM for detecting sepsis using 6-lead and single-lead ECGs was 0.845–0.882. A sensitivity map revealed that the QRS complex and T waves were associated with sepsis. Subgroup analysis was conducted using ECGs from 4,609 patients who were admitted with an infectious disease, and the AUC of the DLM for predicting in-hospital mortality was 0.817 (0.793–0.840). There was a significant difference in the prediction score of DLM using ECG according to the presence of infection in the validation dataset (0.277 vs. 0.574, p < 0.001), including severe acute respiratory syndrome coronavirus 2 (0.260 vs. 0.725, p = 0.018).

Conclusions

The DLM delivered reasonable performance for sepsis screening using 12-, 6-, and single-lead ECGs. The results suggest that sepsis can be screened using not only conventional ECG devices but also diverse life-type ECG machines employing the DLM, thereby preventing irreversible disease progression and mortality.

Prognostic role of N-terminal prohormone of brain natriuretic peptide for patients in the medical intensive care unit with severe sepsis

BACKGROUND

Sepsis is an important cause of mortality in intensive care units worldwide. The increased levels of N-terminal prohormone of brain natriuretic peptide (NT-pro BNP) are related with dysfunction of the cardiovascular system and systemic inflammation. It is uncertain whether this increase reflects sepsis-related cardiac dysfunction that translates to poorer outcomes.

AIMS AND OBJECTIVES

The primary aim of this study was to evaluate the prognostic role of NT-pro BNP on the outcome and duration of hospital stay of patients admitted with sepsis. The secondary objective was to identify other associated risk factors for mortality in sepsis.

PATIENTS AND METHODS

The patients who presented to emergency room with diagnosis of suspected sepsis were studied. Risk factors associated with outcome were studied by univariate analysis. The variables having statistical significance were further included in multivariate analysis to identify the independent predictors of mortality.

RESULTS

A total of 215 patients with sepsis were included in this study. In univariate analyses, NT-pro BNP, procalcitonin, need of mechanical ventilation (MV), blood culture positivity, chronic kidney disease-chronic liver disease CKD-CLD, and diabetes mellitus were predictors of prolonged hospital stay, and it was same for multivariate analysis excluding procalcitonin. In univariate analysis, NT-pro BNP, MV, and DM were risk factors associated with mortality but in multivariate analysis showed significance only with MV and DM.

CONCLUSION

There was a statistically significant correlation between NT-pro BNP levels and mortality. The other factors associated with increased mortality were diabetes mellitus and need of MV. In addition to the above factors, the presence of CKD and CLD was associated with increased duration of hospital stay. There was concordance between increased NT-pro BNP and elevated trop I, s creatinine, need of MV, and CKD.

Ulinastatin protects against sepsis‑induced myocardial injury by inhibiting NLRP3 inflammasome activation

Myocardial injury is the primary manifestation of multiple organ dysfunction during sepsis, however, the mechanisms underlying sepsis-induced myocardial injury remain unclear. Similarly, no effective therapeutics have yet been developed for myocardial injury. In the present study, the role of the NOD-like receptor 3 (NLRP3) inflammasome on cardiac function were characterized and the effects of different ulinastatin (UTI) doses in protecting a septic rat model from myocardial injury were elucidated. To evaluate UTI efficacy on cardiac function, its effects on anti-inflammatory mediators were analyzed and its cardioprotective effects were investigated. It was demonstrated that circulatory levels of tumor necrosis factor-α and interleukin-1β were elevated during sepsis. It was also observed that NLRP3 and caspase-1 expression enhanced post-cecal ligation and puncture (CLP), and that high UTI levels protected against myocardial injury induced by sepsis. To the best of our knowledge, this is the first study to demonstrate that the mechanisms underpinning UTI-mediated myocardial protection were due to the downregulation of the NLRP3/caspase-1/IL-1β signaling pathway. Based on these findings, it is proposed that UTI exerts beneficial effects during sepsis-induced myocardial injury.

Echocardiographic Assessment of Left Ventricular Systolic and Diastolic Functions in Dogs with Severe Sepsis and Septic Shock; Longitudinal Study

Simple Summary

Sepsis is associated with cardiovascular changes. The aim of the study was to determine sepsis-induced myocardial dysfunction in dogs with severe sepsis and septic shock using transthoracic echocardiography. Clinical, laboratory and cardiologic examinations for the septic dogs were performed at admission, 6 and 24 h, and on the day of discharge from the hospital. Left ventricular (LV) systolic dysfunction, LV diastolic dysfunction, and both types of the dysfunction were present in 13%, 70%, and 9% of dogs with sepsis, respectively. Dogs with LV diastolic dysfunction had a worse outcome and short-term mortality. Transthoracic echocardiography can be used for monitoring cardiovascular dysfunction in dogs with sepsis.

Abstract

The purpose of this study was to monitor left ventricular systolic dysfunction (LVSD) and diastolic dysfunction (LVDD) using transthoracic echocardiography (TTE) in dogs with severe sepsis and septic shock (SS/SS). A prospective longitudinal study using 23 dogs with SS/SS (experimental group) and 20 healthy dogs (control group) were carried out. All the clinical, laboratory and cardiologic examinations for the experimental dogs were performed at admission, 6 and 24 h after the start of treatment and on the day of discharge. LVSD was described as LV ejection fraction (LVEF) < 50%. LVDD was determined when the septal mitral annulus early diastolic velocity (LVEm) was <8 cm/s. LVSD and LVDD were present in 3 and 16 dogs with SS/SS, respectively, with both types of dysfunction present in 2 of the dogs. Although all the dogs with LVSD survived, 8 dogs with LVDD did not. The survival period was significantly shorter in dogs with an LVEm < 8 cm/s (1.3 ± 1.4 days). In conclusion, LVDD, rather than LVSD, was a common cardiovascular abnormality in the septic dogs, and this may be a negative prognostic factor. TTE is a useful tool for the identifying and monitoring of myocardial dysfunction in the dogs with SS/SS.

Il12a Deletion Aggravates Sepsis-Induced Cardiac Dysfunction by Regulating Macrophage Polarization

Cardiac dysfunction is a well-recognized complication of sepsis and is associated with the outcome and prognosis of septic patients. Evidence suggests that Il12a participates in the regulation of various cardiovascular diseases, including heart failure, hypertension and acute myocardial infarction. However, the effects of Il12a in sepsis-induced cardiac dysfunction remain unknown. In our study, lipopolysaccharide (LPS) and cecal ligation and puncture (CLP) model were used to mimic sepsis, and cardiac Il12a expression was assessed. In addition, Il12a knockout mice were used to detect the role of Il12a in sepsis-related cardiac dysfunction. We observed for the first time that Il12a expression is upregulated in mice after LPS treatment and macrophages were the main sources of Il12a. In addition, our findings demonstrated that Il12a deletion aggravates LPS-induced cardiac dysfunction and injury, as evidenced by the increased serum and cardiac levels of lactate dehydrogenase (LDH) and cardiac creatine kinase-myocardial band (CK-MB). Moreover, Il12a deletion enhances LPS-induced macrophage accumulation and drives macrophages toward the M1 phenotype in LPS-treated mice. Il12a deletion also downregulated the activity of AMP-activated protein kinase (AMPK) but increased the phosphorylation levels of p65 (p-p65) and NF-κB inhibitor alpha (p-IκBα). In addition, Il12a deletion aggravates CLP-induced cardiac dysfunction and injury. Treatment with the AMPK activator AICAR abolishes the deterioration effect of Il12a deletion on LPS-induced cardiac dysfunction. In conclusion, Il12a deletion aggravated LPS-induced cardiac dysfunction and injury by exacerbating the imbalance of M1 and M2 macrophages. Our data provide evidence that Il12a may represent an attractive target for sepsis-induced cardiac dysfunction.

Early Vitamin C, Hydrocortisone, and Thiamine Treatment for Septic Cardiomyopathy: A Propensity Score Analysis

This study investigated the effectiveness of early vitamin C, hydrocortisone, and thiamine among patients with septic cardiomyopathy. In total, 91 patients with septic cardiomyopathy received a vitamin C protocol in September 2018–February 2020. These patients were compared to 75 patients with septic cardiomyopathy who did not receive a vitamin C protocol in September 2016–February 2018. Relative to the control patients, the treated patients were older and more likely to require mechanical ventilation. The vitamin C protocol was associated with a lower risk of intensive care unit mortality in the propensity score (PS)-matched cohort (aHR: 0.55, 95% CI: 0.30–0.99) and inverse probability of treatment weighting-matched cohort (aHR: 0.67, 95% CI: 0.45–1.00). In the PS-matched cohort (59 patients per group), the vitamin C protocol was associated with decreased values for vasopressor dosage, C-reactive protein concentration, and the Sequential Organ Failure Assessment score during the 4-day treatment period. Patients who started the vitamin C protocol within 2 h after diagnosis (vs. 2–8 h or ≥8 h) had the highest vasopressor weaning rate and the lowest mortality rate. These results suggest that early treatment using a vitamin C protocol might improve organ dysfunction and reduce mortality among patients with septic cardiomyopathy.

Emodin alleviates LPS-induced myocardial injury through inhibition of NLRP3 inflammasome activation

Myocardial injury and cardiovascular dysfunction are serious consequences of sepsis and contribute to high mortality. Currently, the pathogenesis of myocardial injury in sepsis is still unclear, and therapeutic approaches are limited. In this study, we investigated the protective effect of emodin on septic myocardial injury and the underlying mechanism. Lipopolysaccharide (LPS)-induced C57BL/6 mice and cardiomyocytes were used as models of sepsis in vivo and in vitro, respectively. The results showed that emodin alleviated cardiac dysfunction, myocardial injury and improved survival rate in LPS-induced septic mice. Emodin attenuated the levels of inflammatory cytokines and cardiac inflammation induced by LPS. Emodin reduced NOD-like receptor protein 3 (NLRP3) and Gasdermin D (GSDMD) expression in the heart tissue of LPS-induced septic mice. In vitro, emodin alleviated LPS-induced cell injury and inflammation in cardiomyocytes by inhibiting NLRP3 inflammasome activation. In addition, an NLRP3 inhibitor was used to further confirm the function of the NLRP3 inflammasome in LPS-induced myocardial injury. Taken together, our findings suggest that emodin improves LPS-induced myocardial injury and cardiac dysfunction by alleviating the inflammatory response and cardiomyocyte pyroptosis by inhibiting NLRP3 inflammasome activation, which provides a feasible strategy for preventing and treating myocardial injury in sepsis.

Multi-biomarker strategy for prediction of myocardial dysfunction and mortality in sepsis

OBJECTIVE

The present study was to evaluate the feasibility of using the multi-biomarker strategy for the prediction of sepsis-induced myocardial dysfunction (SIMD) and mortality in septic patients.

METHODS

Brain natriuretic peptide (BNP), cardiac troponin I (cTnI), and heart-type fatty acid-binding protein (h-FABP) in 147 septic patients were assayed within 6 h after admission. We also determined the plasma levels of myeloperoxidase (MPO) and pregnancy-associated plasma protein-A (PAPP-A). The receiver operating characteristic (ROC) curve was used to assess the best cutoff values of various single-biomarkers for the diagnosis of SIMD and the prediction of mortality. Also, the ROC curve, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) indices were used to evaluate the feasibility of using multi-biomarkers to predict SIMD and mortality.

RESULTS

Our statistics revealed that only h-FABP independently predicted SIMD (P<0.05). The addition of MPO and cTnI to h-FABP for SIMD prediction provided an NRI of 18.7% (P=0.025) and IDI of 3.3% (P=0.033). However, the addition of MPO or cTnI to h-FABP did not significantly improve the predictive ability of h-FABP to SIMD, as evidenced by the area under the curve (AUC), NRI, and IDI (all P>0.05). A history of shock and MPO were independent predictors of mortality in septic patients (both P<0.05). The addition of PAPP-A and h-FABP to MPO resulted in a mortality prediction with NRI of 25.5% (P=0.013) and IDI of 2.9% (P=0.045). However, this study revealed that the addition of h-FABP or PAPP-A to MPO did not significantly improve the ability to predict mortality, as evidenced by the AUC, NRI, and IDI (all P>0.05).

CONCLUSIONS

The findings of this study indicate that a sensitive and specific strategy for early diagnosis of SIMD and mortality prediction in sepsis should incorporate three biomarkers.

Cardamonin protects against lipopolysaccharide-induced myocardial contractile dysfunction in mice through Nrf2-regulated mechanism

In patients with sepsis, lipopolysaccharide (LPS) from the outer membrane of gram-negative bacteria triggers cardiac dysfunction and heart failure, but target therapy for septic cardiomyopathy remains unavailable. In this study we evaluated the beneficial effects of cardamonin (CAR), a flavone existing in Alpinia plant, on endotoxemia-induced cardiac dysfunction and the underlying mechanisms with focus on oxidative stress and apoptosis. Adult mice were exposed to LPS (4 mg/kg, i.p. for 6 h) prior to functional or biochemical assessments. CAR (20 mg/kg, p.o.) was administered to mice immediately prior to LPS challenge. We found that LPS challenge compromised cardiac contractile function, evidenced by compromised fractional shortening, peak shortening, maximal velocity of shortening/relengthening, enlarged LV end systolic diameter and prolonged relengthening in echocardiography, and induced apoptosis, overt oxidative stress (O2- production and reduced antioxidant defense) associated with inflammation, phosphorylation of NF-κB and cytosolic translocation of transcriptional factor Nrf2. These deteriorative effects were greatly attenuated or mitigated by CAR administration. However, H&E and Masson's trichrome staining analysis revealed that neither LPS challenge nor CAR administration significantly affected cardiomyocyte cross-sectional area and interstitial fibrosis. Mouse cardiomyocytes were treated with LPS (4 µg/mL) for 6 h in the absence or presence of CAR (10 μM) in vitro. We found that addition of CAR suppressed LPS-induced defect in cardiomyocyte shortening, which was nullified by the Nrf2 inhibitor ML-385 or the NF-κB activator prostratin. Taken together, our results suggest that CAR administration protects against LPS-induced cardiac contractile abnormality, oxidative stress, apoptosis, and inflammation through Nrf2- and NF-κB-dependent mechanism.

Melatonin alleviates lipopolysaccharide-induced myocardial injury by inhibiting inflammation and pyroptosis in cardiomyocytes

Background

Melatonin (MT) has been shown to protect against various cardiovascular diseases. However, the effect of MT on lipopolysaccharide (LPS)-induced myocardial injury is poorly understood. This study aims to evaluate the effects of MT on LPS-induced myocardial injury in vitro.

Methods

H9C2 cells were divided into a control group, MT group, LPS group, and MT + LPS group. The control group was treated with sterile saline solution, the LPS group received 8 µg/mL LPS for 24 h, MT + LPS cells were pretreated with 200 µmol/L MT for 2 h then with 8 µg/mL LPS for 24 h, and the MT group received only 200 µmol/L MT for 2 h. The CCK-8 assay and lactate dehydrogenase (LDH) activity assay were used to analyze cell viability and LDH release, respectively. Intracellular reactive oxygen species (ROS) and the rate of pyroptosis were measured using the fluorescent probe dichloro-dihydro-fluorescein diacetate (DCFH-DA) and propidium iodide (PI) staining, respectively. The cell supernatants were used to measure the levels of inflammatory cytokines, including IL-6, TNF-α, and IL-1β by enzyme-linked immunosorbent assay (ELISA). The protein levels of iNOS, COX-2, NF-κB, p-NF-κB, NLRP3, caspase-1, and GSDMD were detected by western blot.

Results

MT pretreatment significantly improved LPS-induced myocardial injury by inhibiting inflammation and pyroptosis in H9C2 cells. Moreover, MT inhibited the activation of the NF-κB pathway, and reduced the expression of inflammation-related proteins (iNOS and COX-2), and pyroptosis-related proteins (NLRP3, caspase-1, and GSDMD).

Conclusions

Our data suggests that MT can alleviate LPS-induced myocardial injury, providing novel insights into the treatment of sepsis-induced myocardial dysfunction.

Study into the reversal of septic shock with landiolol (beta blockade): STRESS-L Study protocol for a randomised trial

INTRODUCTION

In 2013, a single-centre study reported the safe use of esmolol in patients with septic shock and tachycardia who required vasopressor therapy for more than 24 hours. Although not powered to detect a change in mortality, marked improvements were seen in survival (adjusted HR, 0.39; 95% CI, 0.26 to 0.59; p<0.001). Beta blockers are one of the most studied groups of drugs but their effect in septic shock is poorly understood; proposed mechanisms include not only the modulation of cardiac function but also immunomodulation.

METHODS AND ANALYSIS

STRESS-L is a randomised, open-label, non-blinded clinical trial which is enrolling a total of 340 patients with septic shock as defined by Sepsis-3 consensus definition and a tachycardia (heart rate ≥95 beats per minute (bpm)) after vasopressor treatment of at least 24 hours. Standard randomisation (1:1 ratio) allocates patients to receive usual care (according to international standards) versus usual care and a continuous landiolol infusion to reduce the heart rate between 80 and 94 bpm. The primary endpoint is the mean Sequential Organ Failure Assessment score over 14 days from entry into the trial and while in intensive care unit. Results will inform current clinical practice guidelines.

ETHICS AND DISSEMINATION

This trial has clinical trial authorisation from the UK competent authority, the Medicines and Healthcare products Regulatory Agency, and has been approved by the East of England-Essex Research Ethics Committee (reference: 17/EE/0368).The results of the trial will be reported first to trial collaborators. The main report will be drafted by the trial coordinating team, and the final version will be agreed by the Trial Steering Committee before submission for publication, on behalf of the collaboration.

REGISTRATION

The trial is funded by the National Institute for Health Research Efficacy and Mechanism Evaluation (EME) (Project Number: EME-14/150/85) and registered ISRCTN12600919 and EudraCT: 2017-001785-14.

Fangchinoline attenuates cardiac dysfunction in rats with endotoxemia via the inhibition of ERK1/2 and NF-κB p65 phosphorylation

Background

Cardiac dysfunction is a complication commonly encountered by patients with endotoxemia. Fangchinoline (Fan) is a natural bisbenzylisoquinoline alkaloid. This study aimed to investigate the cardioprotective effect of Fan against lipopolysaccharide (LPS)-induced acute cardiac dysfunction.

Methods

Rats were administered with Baicalin (100 mg/kg) and Fan (30 or 60 mg/kg) via intraperitoneal injection (i.p.) for 3 days, followed by LPS treatment (10 mg/kg, i.p.). The rats were randomly grouped (n=10): the control group, the LPS group, the LPS + Baicalin group, the LPS + Fan groups. Echocardiography and hematoxylin and eosin (HE) staining were performed to detect cardiac dysfunction. Cardiac function were also determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), ELISA, and western blot, respectively. The protective mechanisms of Fan were analyzed by western blot and qRT-PCR.

Results

LPS induced the depression of cardiac function, myocardial inflammation, and apoptosis. These changes were associated with decreased GRP78 and GADD34, increased C/EBP-homologous protein (CHOP) and cleaved caspase-12. Fan significantly reduced the release of inflammatory cytokines such as monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-18, and IL-6. Furthermore, Fan treatment increased superoxide dismutase (SOD) and decreased malondialdehyde (MDA. Notably, Fan inhibited myocardial apoptosis following ER stress in the LPS-induced rat model and stimulated phosphorylation activation of ERK1/2 and NF-κB p65 proteins.

Conclusions

Fan deficiency alleviated LPS-induced endotoxemia in rats. Therefore, Fan may be a new therapeutic approach for the treatment of cardiac dysfunction.