Elevated Plasma Histone H4 Levels Are an Important Risk Factor in the Development of Septic Cardiomyopathy

Types of Septic Cardiomyopathy: Prognosis and Influencing Factors - A Clinical Study

Objective

To explore the prognostic outcomes associated with different types of septic cardiomyopathy and analyze the factors that exert an influence on these outcomes.

Methods

The data collected within 24 hours of ICU admission included cardiac troponin I (cTnI), N-terminal pro-Brain Natriuretic Peptide (NT-proBNP); SOFA (sequential organ failure assessment) scores, and the proportion of vasopressor use. Based on echocardiographic outcomes, septic cardiomyopathy was categorized into left ventricular (LV) systolic dysfunction, LV diastolic dysfunction, and right ventricular (RV) systolic dysfunction. Differences between the mortality and survival groups, as well as between each cardiomyopathy subgroup and the non-cardiomyopathy group were compared, to explore the influencing factors of cardiomyopathy.

Results

A cohort of 184 patients were included in this study, with LV diastolic dysfunction having the highest incidence rate (43.5%). The mortality group had significantly higher SOFA scores, vasopressor use, and cTnI levels compared to the survival group; the survival group had better LV diastolic function than the mortality group (p < 0.05 for all). In contrast to the non-cardiomyopathy group, each subgroup within the cardiomyopathy category exhibited elevated levels of cTnI. The subgroup with left ventricular diastolic dysfunction demonstrated a higher prevalence of advanced age, hypertension, diabetes mellitus, coronary artery disease, and an increased mortality rate; the RV systolic dysfunction subgroup had higher SOFA scores and NT-proBNP levels, and a higher mortality rate (P < 0.05 for all); the LV systolic dysfunction subgroup had a similar mortality rate (P > 0.05).

Conclusion

Patients with advanced age, hypertension, diabetes mellitus, or coronary artery disease are more prone to develop LV diastolic dysfunction type of cardiomyopathy; cardiomyopathy subgroups had higher levels of cTnI. The RV systolic dysfunction cardiomyopathy subgroup had higher SOFA scores and NT-proBNP levels. The occurrence of RV systolic dysfunction in patients with sepsis significantly increased the mortality rate.

ALDH2 mitigates LPS-induced cardiac dysfunction, inflammation, and apoptosis through the cGAS/STING pathway

BACKGROUND

Sepsis is a severe syndrome of organ dysfunction that often leads to cardiac dysfunction and endangers life. The role of mitochondrial aldehyde dehydrogenase 2 (ALDH2) in LPS-induced myocardial injury is unclear. The purpose of this study was to assess the role of ALDH2 in lipopolysaccharide (LPS)-induced myocardial injury and the regulatory mechanism and to identify potential therapeutic strategies for treating this condition.

METHODS

An in vivo model was established by 12 h of LPS (10 mg/kg, intraperitoneal injection) stimulation, and an in vitro model was generated by stimulating H9C2 cells with LPS (10 μg/ml) for 12 h. We then used the ALDH2 activator Alda-1 and the ALDH2 inhibitor daidzin to assess their effects on LPS-induced cardiac injury. Cardiac function in mice was evaluated by using cardiac ultrasound. We used various methods to evaluate inflammation, apoptosis, and oxidative stress, including ELISA, flow cytometry, JC-1 staining, Western blotting, and DCFH-DA staining. Additionally, we used a small interfering RNA (siRNA) to knock down cyclic GMP-AMP synthase (cGAS) to further investigate the relationship between ALDH2 and cGAS in LPS-induced cardiac injury.

RESULTS

LPS-induced cardiac dysfunction and increased the levels of the cardiac injury markers creatine kinase-MB (CKMB) and lactate dehydrogenase (LDH) in vivo. This change was accompanied by an increase in reactive oxygen species (ROS) levels, which exacerbated the oxidative stress response and regulated apoptosis through cleaved caspase-3, BAX, BCL-2. The expression of inflammatory cytokines such as IL-6/IL-1β/TNF-α was also upregulated. However, these effects were reversed by pretreatment with Alda-1 via the inhibition of cGAS/stimulator of interferon genes (STING) signaling pathway. Interestingly, LPS, Alda-1 and daidzin altered the activity of ALDH2 but did not regulate its protein expression. Knocking down cGAS in H9C2 cardiomyocytes alleviated LPS-induced cardiac inflammation, apoptosis, and ROS production and weakened the synergistic effect of daidzin.

CONCLUSION

We demonstrated that ALDH2 alleviated LPS-induced cardiac dysfunction, inflammation, and apoptosis through the cGAS/STING signaling pathway, thereby protecting against LPS-induced cardiac injury. This study identifies a novel therapeutic approach for treating sepsis-induced cardiomyopathy (SIC).

Xanthohumol ameliorates cardiac injury induced by sepsis in a mice model: role of toll-like receptor 4

Sepsis, a life-threatening condition arising from infection, often results in multi-organ failure, including cardiac dysfunction. This study investigated Xanthohumol, a natural compound, and its potential mechanism of action to enhance heart function following sepsis. A total of twenty-four adult male Swiss albino mice were allocated randomly to one of four equal groups (n=6): sham, CLP, vehicle Xanthohumol the same amount of DMSO injected IP 10 minutes before the CLP, and Xanthohumol group (0.4 mg/kg of Xanthohumol administered IP before the CLP process). Toll-like receptor 4, pro-inflammatory mediators, anti-inflammatory markers, oxidative stress indicators, apoptosis markers, and serum cardiac damage biomarkers were measured in the cardiac tissue using ELISA. Data with normal distribution were analyzed using t-test and ANOVA tests (p<0.05). In comparison to the sham group, the sepsis group had significantly higher levels of TLR-4, IL-6, TNF-α, MIF, F2-isoprostane, caspase-3, cTn-I, and CK-MB, while the pre-treated group with Xanthohumol had significantly lower levels (p<0.05) of these markers than the sepsis group. Bcl-2 showed no significant difference in Xanthohumol pre-treated group relative to the sepsis group, while IL-10 was significantly elevated. Xanthohumol dramatically reduced cardiac tissue injury (p<0.05) relative to the CLP group. By blocking the downstream signal transduction pathways of TLR-4 and NF-kB, Xanthohumol was shown to lessen cardiac damage in male mice during CLP-induced polymicrobial sepsis.

Effect of Sulforaphane on cardiac injury induced by sepsis in a mouse model: Role of toll-like receptor 4

As sepsis is associated with a 50% increase in mortality, sepsis-induced cardiomyopathy has become a critical topic. A multidisciplinary approach is required for the diagnosis and treatment of septic cardiomyopathy. This study looked at Sulforaphane, a natural product that aims to evaluate cardiac function after sepsis, and its likely mechanism of action. Twenty-four adult male Swiss albino mice were randomly divided into 4 equal groups (n=6): sham, CLP, vehicle Sulforaphane (the same amount of DMSO injected IP one hour before the CLP), and Sulforaphane group (one hour before the CLP, a 5mg/kg dose of Sulforaphane was injected). Cardiac tissue levels of toll-like receptor 4 (TLR-4), pro-inflammatory mediators, anti-inflammatory markers, oxidative stress markers, apoptosis markers, and serum cardiac damage biomarkers were assessed using ELISA. Statistical analyses, including t-tests and ANOVA tests, were performed with a significance level of 0.05 for normally distributed data. Compared to the sham group, the sepsis group had significantly elevated levels of TLR-4, IL-6, TNF-α, MIF, F2-isoprostane, caspase-3, cTn-I, and CK-MB (p<0.05). In contrast, the Sulforaphane pre-treated group demonstrated significantly lower levels of these markers (p<0.05). Additionally, Bcl-2 levels were significantly reduced (p<0.05) in the Sulforaphane group. Sulforaphane administration also significantly attenuated cardiac tissue injury (p<0.05). The findings suggest that Sulforaphane can decrease heart damage in male mice during CLP-induced polymicrobial sepsis by suppressing TLR-4/NF-kB downstream signal transduction pathways.

Early Diastolic Peak Velocity of Mitral Valve Annulus and Right Ventricular Systolic Tricuspid Annular Velocity as Predictors in Assessing Prognosis of Patients with Sepsis

Objective

To analyze the epidemiological data of patients with septic cardiomyopathy and investigate the relationship between ultrasonic parameters and prognosis of patients with sepsis.

Methods

In this study, we enrolled patients with sepsis who were treated at the Department of Critical Care Medicine in the Beijing Electric Power Hospital (No.1 Taipingqiao Xili, Fengtai District, Beijing) from January 2020 to June 2022. All patients received standardized treatment. Their general medical status and 28-day prognosis were recorded. Transthoracic echocardiography was performed within 24 hours after admission. We compared the ultrasound indexes between the mortality group and the survival group at the end of 28 days. We included parameters with significant difference in the logistic regression model to identify the independent risk factors for prognosis and evaluated their predictive value using receiver operating characteristic (ROC) curve.

Results

We included 100 patients with sepsis in this study; the mortality rate was 33% and the prevalence rate of septic cardiomyopathy was 49%. The peak e' velocity and right ventricular systolic tricuspid annulus velocity (RV-Sm) of the survival group were significantly higher than those of the mortality group (P < 0.05). Results of logistic regression analysis showed that the peak e' velocity and RV-Sm were independent risk factors for prognosis. The area under curve of the peak e' velocity and the RV-Sm was 0.657 and 0.668, respectively (P < 0.05).

Conclusion

The prevalence rate of septic cardiomyopathy in septic patients is high. In this study, we found that the peak e' velocity and right ventricular systolic tricuspid annulus velocity were important predictors of short-term prognosis.

Role of neutrophil extracellular traps in inflammatory evolution in severe acute pancreatitis

ABSTRACT

Severe acute pancreatitis (SAP) is a life-threatening acute abdominal disease with two peaks of death: the first in the early stage, characterized by systemic inflammatory response-associated organ failure; and the second in the late stage, characterized by infectious complications. Neutrophils are the main immune cells participating in the whole process of SAP. In addition to the traditional recognition of neutrophils as the origination of chemokine and cytokine cascades or phagocytosis and degranulation of pathogens, neutrophil extracellular traps (NETs) also play an important roles in inflammatory reactions. We reviewed the role of NETs in the occurrence and development of SAP and its fatal complications, including multiple organs injury, infected pancreatic necrosis, and thrombosis. This review provides novel insights into the involvement of NETs throughout the entire process of SAP, showing that targeting NETs might be a promising strategy in SAP treatment. However, precision therapeutic options targeting NETs in different situations require further investigation.

Histone H4K20 Trimethylation Is Decreased in Murine Models of Heart Disease

Heart disease is the leading cause of death in the developed world, and its comorbidities such as hypertension, diabetes, and heart failure are accompanied by major transcriptomic changes in the heart. During cardiac dysfunction, which leads to heart failure, there are global epigenetic alterations to chromatin that occur concomitantly with morphological changes in the heart in response to acute and chronic stress. These epigenetic alterations include the reversible methylation of lysine residues on histone proteins. Lysine methylations on histones H3K4 and H3K9 were among the first methylated lysine residues identified and have been linked to gene activation and silencing, respectively. However, much less is known regarding other methylated histone residues, including histone H4K20. Trimethylation of histone H4K20 has been shown to repress gene expression; however, this modification has never been examined in the heart. Here, we utilized immunoblotting and mass spectrometry to quantify histone H4K20 trimethylation in three models of cardiac dysfunction. Our results show that lysine methylation at this site is differentially regulated in the cardiomyocyte, leading to increased H4K20 trimethylation during acute hypertrophic stress in cell models and decreased H4K20 trimethylation during sustained ischemic injury and cardiac dysfunction in animal models. In addition, we examined publicly available data sets to analyze enzymes that regulate H4K20 methylation and identified two demethylases (KDM7B and KDM7C) and two methyltransferases (KMT5A and SMYD5) that were all differentially expressed in heart failure patients. This is the first study to examine histone H4K20 trimethylation in the heart and to determine how this post-translational modification is differentially regulated in multiple models of cardiac disease.

Identification of novel biomarkers in septic cardiomyopathy via integrated bioinformatics analysis and experimental validation

Purpose: Septic cardiomyopathy (SCM) is an important world public health problem with high morbidity and mortality. It is necessary to identify SCM biomarkers at the genetic level to identify new therapeutic targets and strategies.

Method: DEGs in SCM were identified by comprehensive bioinformatics analysis of microarray datasets (GSE53007 and GSE79962) downloaded from the GEO database. Subsequently, bioinformatics analysis was used to conduct an in-depth exploration of DEGs, including GO and KEGG pathway enrichment analysis, PPI network construction, and key gene identification. The top ten Hub genes were identified, and then the SCM model was constructed by treating HL-1 cells and AC16 cells with LPS, and these top ten Hub genes were examined using qPCR.

Result: STAT3, SOCS3, CCL2, IL1R2, JUNB, S100A9, OSMR, ZFP36, and HAMP were significantly elevated in the established SCM cells model.

Conclusion: After bioinformatics analysis and experimental verification, it was demonstrated that STAT3, SOCS3, CCL2, IL1R2, JUNB, S100A9, OSMR, ZFP36, and HAMP might play important roles in SCM.

Risk factors of postoperative septic cardiomyopathy in perioperative sepsis patients

Objective

This study aimed to clarify the relevant risk factors of septic cardiomyopathy (SCM) in perioperative sepsis patients.

Methods

This retrospective study evaluated patients who were diagnosed with sepsis during the perioperative period and postoperatively admitted to the intensive care unit (ICU) in the Second Affiliated Hospital of Soochow University, the First Affiliated Hospital of Soochow University, and the Suzhou Municipal Hospital between January 2017 and November 2020. They were divided into two groups as the septic cardiomyopathy group (SCM group) and the non-SCM group (NSCM group). Factors with P < 0.1 were compared between groups and were analyzed by multivariate logistic regression to screen the risk factors of sepsis cardiomyopathy. The area under the receiver operating characteristic (ROC) curve was used to verify the discriminative ability of multivariate logistic regression results. Hosmer-Lemeshow goodness of fit test was used to verify the calibration ability of multiple logistic regression results.

Result

Among the 269 patients, 49 patients had SCM. Sequential Organ Failure Assessment (SOFA) score (adjusted odds ratio [AOR] = 2.535, 95% confidence interval (CI): 1.186-1.821, P = 0.000]) and endoscopic surgery (AOR = 3.154, 95% CI: 1.173-8.477, P = 0.023]) were identified to be independent risk factors for SCM. Patients with a SOFA score ≥ 7 had a 46.831-fold higher risk of SCM (AOR =46.831, 95% CI: 10.511-208.662, P < 0.05). The multivariate logistic regression results had good discriminative (area under the curve: 0.902 [95% CI: 0.852-0.953]) and calibration (c² = 4.401, P = 0.819) capabilities. The predictive accuracy was 86.2%. The rates of mechanical ventilation and tracheotomy were significantly higher in the SCM group than in the NSCM group (both P < 0.05). The SCM group also had a significantly longer duration of mechanical ventilation (P < 0.05) and significantly higher rates of continuous renal replacement therapy (CRRT) and CRRT-related mortality (P < 0.05). Further, the total length of stay and hospitalization cost were significantly higher in the SCM group than in the NSCM group (P < 0.05).

Conclusion

Endoscopic surgery and SOFA score ≥ 7 during postoperative ICU admission were independent risk factors for SCM within 48 hours postoperatively in patients with perioperative sepsis.

Exploratory Investigation of the Plasma Proteome Associated with the Endotheliopathy of Trauma

BACKGROUND

The endotheliopathy of trauma (EoT) is associated with increased mortality following injury. Herein, we describe the plasma proteome related to EoT in order to provide insight into the role of the endothelium within the systemic response to trauma.

METHODS

99 subjects requiring the highest level of trauma activation were included in the study. Enzyme-linked immunosorbent assays of endothelial and catecholamine biomarkers were performed on admission plasma samples, as well as untargeted proteome quantification utilizing high-performance liquid chromatography and tandem mass spectrometry.

RESULTS

Plasma endothelial and catecholamine biomarker abundance was elevated in EoT. Patients with EoT (n = 62) had an increased incidence of death within 24 h at 21% compared to 3% for non-EoT (n = 37). Proteomic analysis revealed that 52 out of 290 proteins were differentially expressed between the EoT and non-EoT groups. These proteins are involved in endothelial activation, coagulation, inflammation, and oxidative stress, and include known damage-associated molecular patterns (DAMPs) and intracellular proteins specific to several organs.

CONCLUSIONS

We report a proteomic profile of EoT suggestive of a surge of DAMPs and inflammation driving nonspecific activation of the endothelial, coagulation, and complement systems with subsequent end-organ damage and poor clinical outcome. These findings support the utility of EoT as an index of cellular injury and delineate protein candidates for therapeutic intervention.

Effect of Glucose-Insulin-Potassium Infusion on Hemodynamics in Patients with Septic Shock

BACKGROUND: Glucose-insulin-potassium (GIK) demonstrates a cardioprotective effect by providing metabolic support and anti-inflammatory action, and may be useful in septic myocardial depression. AIM: The aim of this study was to assess role of GIK infusion in improving hemodynamics in patients with septic shock in addition to its role in myocardial protection and preventing occurrence of sepsis-induced myocardial dysfunction and sepsis-induced arrhythmias. METHODS: This study was conducted on 75 patients admitted to the Critical Care Department in Cairo University Hospital with the diagnosis of septic shock during the period from January 2019 to December 2019. Patients were divided into two groups; first group was managed according to the last guidelines of surviving sepsis campaign and was subjected to the GIK infusion protocol while second group was managed following the last guidelines of surviving sepsis campaign only without adding GIK infusion. RESULTS: Patients in the GIK group showed better lactate clearance (50% vs. 46.7%) and less time needed for successful weaning of vasopressors than the control group (3.57±1.16 vs. 3.6±1.45 days) thought not reaching statistical significance. There was no statistically significant difference between both groups regarding development of septic-induced cardiomyopathy (16.7% in the control group vs. 13.3% in the GIK group); however, patients with hypodynamic septic shock showed better improvement in hemodynamic profile in the GIK group. Sepsis-induced arrhythmias occurred more in patients of the control group than in patients of the GIK group with no statistically significant difference between both groups (33.3% vs. 20%, p = 0.243). Few side effects were developed as a result of using GIK infusion protocol. CONCLUSIONS: GIK may help in improving hemodynamics and weaning of vasopressors in patients with refractory septic shock and those with septic induced cardiomyopathy. The use of GIK was well tolerated with minimal adverse reactions.

Targeting the eCIRP/TREM-1 interaction with a small molecule inhibitor improves cardiac dysfunction in neonatal sepsis

Background

Neonatal sepsis and the associated myocardial dysfunction remain a leading cause of infant mortality. Extracellular cold-inducible RNA-binding protein (eCIRP) acts as a ligand of triggering receptor expressed on myeloid cells-1 (TREM-1). M3 is a small CIRP-derived peptide that inhibits the eCIRP/TREM-1 interaction. We hypothesize that the eCIRP/TREM-1 interaction in cardiomyocytes contributes to sepsis-induced cardiac dysfunction in neonatal sepsis, while M3 is cardioprotective.

Methods

Serum was collected from neonates in the Neonatal Intensive Care Unit (NICU). 5–7-day old C57BL/6 mouse pups were used in this study. Primary murine neonatal cardiomyocytes were stimulated with recombinant murine (rm) CIRP with M3. TREM-1 mRNA and supernatant cytokine levels were assayed. Mitochondrial oxidative stress, ROS, and membrane potential were assayed. Neonatal mice were injected with rmCIRP and speckle-tracking echocardiography was conducted to measure cardiac strain. Sepsis was induced by i.p. cecal slurry. Mouse pups were treated with M3 or vehicle. After 16 h, echocardiography was performed followed by euthanasia for tissue analysis. A 7-day survival study was conducted.

Results

Serum eCIRP levels were elevated in septic human neonates. rmCIRP stimulation of cardiomyocytes increased TREM-1 gene expression. Stimulation of cardiomyocytes with rmCIRP upregulated TNF-α and IL-6 in the supernatants, while this upregulation was inhibited by M3. Stimulation of cardiomyocytes with rmCIRP resulted in a reduction in mitochondrial membrane potential (MMP) while M3 treatment returned MMP to near baseline. rmCIRP caused mitochondrial calcium overload; this was inhibited by M3. rmCIRP injection impaired longitudinal and radial cardiac strain. Sepsis resulted in cardiac dysfunction with a reduction in cardiac output and left ventricular end diastolic diameter. Both were improved by M3 treatment. Treatment with M3 attenuated serum, cardiac, and pulmonary levels of pro-inflammatory cytokines compared to vehicle-treated septic neonates. M3 dramatically increased sepsis survival.

Conclusions

Inhibition of eCIRP/TREM-1 interaction with M3 is cardioprotective, decreases inflammation, and improves survival in neonatal sepsis.

Trial registration Retrospectively registered.

Current Status of Septic Cardiomyopathy: Basic Science and Clinical Progress

Septic cardiomyopathy (SCM) is a complication that is sepsis-associated cardiovascular failure. In the last few decades, there is progress in diagnosis and treatment despite the lack of consistent diagnostic criteria. According to current studies, several hypotheses about pathogenic mechanisms have been revealed to elucidate the pathophysiological characteristics of SCM. The objective of this manuscript is to review literature from the past 5 years to provide an overview of current knowledge on pathogenesis, diagnosis and treatment in SCM.