Sepsis-induced Myocardial Depression Research Articles

Recent research on pyroptosis in sepsis-induced myocardial depression

Sepsis-induced myocardial depression (SIMD), a common complication of sepsis, is one of the main causes of death in patients with sepsis. The pathogenesis of SIMD is complicated, and the process of SIMD remains incompletely understood, with no single or definitive mechanism fully elucidated. Notably, pyroptosis, as a pro-inflammatory programmed cell death, is characterized by Gasdermin-mediated formation of pores on the cell membrane, cell swelling, and cell rupture accompanied by the release of large amounts of inflammatory factors and other cellular contents. Mechanistically, pyroptosis is mainly divided into the canonical pathway mediated by caspase-1 and the non-canonical pathway mediated by caspase-4/5/11. Pyroptosis has been confirmed to participate in various inflammation-associated diseases. In recent years, more and more studies have shown that pyroptosis is also involved in the occurrence and development of SIMD. This article reviews the molecular mechanisms of pyroptosis and its research progress in SIMD, aiming to provide novel strategies and targets for the treatment of SIMD.

A novel long noncoding RNA-lncRNA-AABR07066529.3 alleviates inflammation, apoptosis, and pyroptosis by inhibiting MyD88 in lipopolysaccharide-induced myocardial depression.

Sepsis-induced myocardial depression (SIMD) is common in pediatric intensive care units and seriously threatens children's health. Recently, long noncoding RNAs (lncRNAs) have been showed to play important roles in various diseases; however, its role in SIMD is unclear. In this study, we used lipopolysaccharide (LPS)-treated rats and H9c2 cardiomyocytes to mimic SIMD in vivo and in vitro. We found that the expression of a novel lncRNA, we named lncRNA-AABR07066529.3, was elevated in LPS-induced rat heart tissue and H9c2 cardiomyocytes. In addition, LPS-induced inflammation, apoptosis, and pyroptosis were significantly exacerbated after lncRNA-AABR07066529.3 knockdown. Moreover, we found that myeloid differentiation factor 88 (MyD88) was upregulated in LPS-treated groups and was inhibited by lncRNA-AABR07066529.3. Besides, MyD88 knockdown abolished lncRNA-AABR07066529.3 silencing effects on inflammation, apoptosis, and pyroptosis induced by LPS in H9c2 cardiomyocytes. In our study, we found lncRNA-AABR07066529.3 exerted protective effects on LPS-induced cardiomyocytes by regulating MyD88 and might serve as a potential treatment target for SIMD.

DJ-1 Deficiency Protects against Sepsis-Induced Myocardial Depression

Oxidative stress is considered one of the early underlying contributors of sepsis-induced myocardial depression. DJ-1, also known as PARK7, has a well-established role as an antioxidant. We have previously shown, in a clinically relevant model of polymicrobial sepsis, DJ-1 deficiency improved survival and bacterial clearance by decreasing ROS production. In the present study, we investigated the role of DJ-1 in sepsis-induced myocardial depression. Here we compared wildtype (WT) with DJ-1 deficient mice at 24 and 48 h after cecal ligation and puncture (CLP). In WT mice, DJ-1 was increased in the myocardium post-CLP. DJ-1 deficient mice, despite enhanced inflammatory and oxidative responses, had an attenuated hypertrophic phenotype, less apoptosis, improved mitochondrial function, and autophagy, that was associated with preservation of myocardial function and improved survival compared to WT mice post-CLP. Collectively, these results identify DJ-1 as a regulator of myocardial function and as such, makes it an attractive therapeutic target in the treatment of early sepsis-induced myocardial depression.

CK1α protects cardiomyocytes in sepsis-induced myocardial depression by repressing the interaction of ATG5 with myD88/NF-kappaB signaling

Purpose: To explore the effects of casein kinase 1α (CK1α) on cardiomyocytes in sepsis-induced myocardial depression.Methods: Colorectal ligation puncture (CLP) surgery was performed for the establishment of the mouse model. Total RNAs of the lungs, kidneys, liver tissues and alveolar macrophages were extracted using TRIzol™ reagent, while gene expression analysis was performed by quantitative polymerase chain reaction (qPCR) following reverse transcription. Western blot was employed to evaluate protein expression, and echocardiography was conducted to assess cardiac function. Immunofluorescent assay was performed to determine the expression of p-FOXO3a in primary cardiomyocytes.Results: Inhibition of CK1α impaired autophagy influx, and significantly increased inflammatory cytokines in H9C2 cells after lipopolysaccharide (LPS) treatment (p < 0.05). Moreover, aberrant activation of the Toll-like receptor 4(TLR4)/myD88/NF-kappaB pathway was observed in the H9C2 cell line after LPS treatment (p < 0.05). Immunoprecipitation analysis revealed an interaction between MyD88 and autophagy-related gene 5 (Atg5), and cardiac dysfunction in mice intravenously injectedwith an adenoviral vector containing shRNA (casein kinase 1 α) CSNK1A1 was suppressed (p < 0.05). In contrast, overexpression of CK1α remarkably improved cardiac systolic function (p < 0.05), the expression of inflammatory cytokines was repressed, and autophagy was enhanced in the hearts of mice with the specific overexpression of CSNK1A1 in cardiomyocytes (p < 0.05). In Atg5-deficient mice pretreated with DC661, the protective effect of adenoviral vector containing CK1α overexpression was eliminated.Conclusion: CK1α protects cardiomyocytes during sepsis after the inhibition of TLR/MyD88/NF-kappaBpathway via interaction of Atg5 with MyD88. The results of the current study may provide new insights into the treatment of sepsis-induced myocardial depression.

Silencing of Long Noncoding RNA MIAT Contributes to Relieving Sepsis-Induced Myocardial Depression via the NF-κB Axis

IntroductionSepsis represents a life-threatening disease caused by a series of infections, which may be complicated with severe myocardial depression (MD). Long noncoding RNAs (lncRNAs) are closely related to sepsis-induced myocardial depression (SIMD). This study aimed to seek out the mechanism of lncRNA myocardial infarction-associated transcript (MIAT) in the growth of SIMD. MethodsVenous blood samples were collected from 62 patients with sepsis; the sepsis rat model was established with 15 mg/kg lipopolysaccharide (LPS), and the H9C2 cardiomyocyte injury model was established with 1 μg/mL LPS. In the rat and cardiomyocyte models, MIAT was inhibited. The expression of MIAT in normal tissues and SIMD tissues was detected. Then, the functional assays of MIAT were performed in rats and H9C2 cells for detection of cardiac function, hemodynamics, inflammation response, myocardial function, oxidative stress, tissue stainings, and cardiomyocyte viability and apoptosis. Western blot analysis was used to measure the levels of apoptosis-related proteins and the nuclear factor kappa B (NF-κB) axis-related proteins. ResultsMIAT was highly expressed in SIMD patients. Silencing MIAT alleviated inflammation and apoptosis and improved myocardial function in SIMD rats by downregulating the NF-κB axis. In LPS-induced H9C2 cardiomyocytes, silencing MIAT alleviated inflammation and oxidative stress and inhibited apoptosis by downregulating the NF-κB axis, thus mitigating cardiomyocyte injury. ConclusionsMIAT could assist the diagnosis of SIMD and might affect the progression of SIMD by regulating the NF-κB pathway.

Integrated insights into the mechanisms underlying sepsis-induced myocardial depression using a quantitative global proteomic analysis

Sepsis-induced myocardial depression is common among patients in the intensive care unit; however, the exact mechanisms underlying this condition remain unclear. We investigated differences in the expression of specific proteins and determined the potential functions of the proteins in a rat model of lipopolysaccharide-induced septic shock. Left ventricular tissue was excised from 16 rats (sepsis group, 8; control group, 8) and analysed. Quantitative analysis of the global proteome was performed using 4D label-free technique. Bioinformatic analyses were conducted based on differentially expressed (DE) proteins. Parallel reaction monitoring (PRM) validation for selected proteins and western blotting for selected global protein modifications in heart tissues were also performed. As a result, out of 3653 proteins identified, 108 were expressed differentially between the two groups. The bioinformatic analyses revealed that DE proteins play important roles in metabolism- and immune-related pathways. PRM results supported the plausibility and reliability of the proteomics data. Modification of heart tissue acetyllysine, succinyllysine, 2-hydroxyisobutyryllysine, and lactyllysine revealed clear differences between the two groups, indicating the effects of protein modification. Our study suggested that expression patterns of global proteins in heart tissue were different between the two groups. These results provide new valuable information on the possible mechanisms underlying sepsis-induced myocardial depression. SignificanceThe expression patterns of global proteins in the heart tissues of patients with sepsis and control groups remain unknown. In this study, we used the 4D label-free proteomics technique to compare differentially expressed (DE) proteins between the sepsis and control groups. We identified 3653 proteins, 108 of which were expressed differentially between the sepsis and control groups. Further bioinformatic analyses revealed that DE proteins play critical roles in metabolism- and immune-related processes and pathways. Interestingly, modification of heart tissue acetyllysine, succinyllysine, 2-hydroxyisobutyryllysine, and lactyllysine revealed clear differences between the sepsis and control groups. The findings of this study improve our understanding of the basic molecular mechanisms underlying sepsis-induced myocardial depression.

Venoarterial extracorporeal membrane oxygenation as mechanical circulatory support in adult septic shock: a systematic review and meta-analysis with individual participant data meta-regression analysis

BackgroundWhile recommended by international societal guidelines in the paediatric population, the use of venoarterial extracorporeal membrane oxygenation (VA ECMO) as mechanical circulatory support for refractory septic shock in adults is controversial. We aimed to characterise the outcomes of adults with septic shock requiring VA ECMO, and identify factors associated with survival.MethodsWe searched Pubmed, Embase, Scopus and Cochrane databases from inception until 1st June 2021, and included all relevant publications reporting on > 5 adult patients requiring VA ECMO for septic shock. Study quality and certainty in evidence were assessed using the appropriate Joanna Briggs Institute checklist, and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, respectively. The primary outcome was survival to hospital discharge, and secondary outcomes included intensive care unit length of stay, duration of ECMO support, complications while on ECMO, and sources of sepsis. Random-effects meta-analysis (DerSimonian and Laird) were conducted.Data synthesisWe included 14 observational studies with 468 patients in the meta-analysis. Pooled survival was 36.4% (95% confidence interval [CI]: 23.6%–50.1%). Survival among patients with left ventricular ejection fraction (LVEF) < 20% (62.0%, 95%-CI: 51.6%–72.0%) was significantly higher than those with LVEF > 35% (32.1%, 95%-CI: 8.69%–60.7%, p = 0.05). Survival reported in studies from Asia (19.5%, 95%-CI: 13.0%–26.8%) was notably lower than those from Europe (61.0%, 95%-CI: 48.4%–73.0%) and North America (45.5%, 95%-CI: 16.7%–75.8%). GRADE assessment indicated high certainty of evidence for pooled survival.ConclusionsWhen treated with VA ECMO, the majority of patients with septic shock and severe sepsis-induced myocardial depression survive. However, VA ECMO has poor outcomes in adults with septic shock without severe left ventricular depression. VA ECMO may be a viable treatment option in carefully selected adult patients with refractory septic shock.

Long non-coding RNA GAS5 aggravates myocardial depression in mice with sepsis via the microRNA-449b/HMGB1 axis and the NF-κB signaling pathway.

Sepsis is a common cause of deaths of patients in intensive care unit. The study aims to figure out the role of long non-coding RNA (lncRNA) GAS5 in the myocardial depression in mice with sepsis. Cecal ligation and puncture (CLP) was applied to induce sepsis in mice, and then the heart function, myocardium structure, and the inflammatory response were evaluated. Differentially expressed lncRNAs in mice with sepsis were identified. Then gain- and loss-of-functions of GAS5 were performed in mice to evaluate its role in mouse myocardial depression. The lncRNA-associated microRNA (miRNA)–mRNA network was figured out via an integrative prediction and detection. Myocardial injury was observed by overexpression of high-mobility group box 1 (HMGB1) in septic mice with knockdown of GAS5 expression. Activity of NF-κB signaling was evaluated, and NF-κB inhibition was induced in mice with sepsis and overexpression of GAS5. Collectively, CLP resulted in myocardial depression and injury, and increased inflammation in mice. GAS5 was highly expressed in septic mice. GAS5 inhibition reduced myocardial depression, myocardial injury and inflammation responses in septic mice. GAS5 was identified to bind with miR-449b and to elevate HMGB1 expression, thus activating the NF-κB signaling. HMGB1 overexpression or NF-κB inactivation reduced the GAS5-induced myocardial depression and inflammation in septic mice. Our study suggested that GAS5 might promote sepsis-induced myocardial depression via the miR-449b/HMGB1 axis and the following NF-κB activation.

Comparative transcriptome analysis of\xa0transcripts of uncertain coding potential in septic myocardial depression

BackgroundSeptic shock with myocardial depression is very common in intensive care units. However, the exact molecular mechanisms underlying sepsis-induced myocardial depression remain unclear. Whether the profiles of transcripts of uncertain coding potential (TUCPs) differ between patients with and without myocardial depression is also unknown. Our study aimed to find expression differences between groups of TUCPs and determine their potential functions in a preclinical model.MethodsWe generated rat models of hypodynamic septic shock induced by lipopolysaccharide. A total of 12 rats were established and left ventricular tissue from each was collected. We performed RNA-seq to identify TUCPs in each sample. Transcripts with an corrected P value of < 0.05 were defined as differentially expressed (DE). We also performed GO terms and KEGG analysis to identify the potential functions of DE TUCPs.ResultsA total of 4,851 TUCPs were identified in heart samples, 85 of which were expressed differently between the sepsis and control groups. Further bioinformatic analyses suggested that TUCPs play important roles in myocardial contraction, energy regulation, and metabolic processes, and are also involved in the regulation of several pathways.ConclusionOur results demonstrate that TUCPs both participate in and mediate the pathological process of myocardial depression. Our study improves the understanding of the basic molecular mechanisms underlying myocardial depression from a novel perspective.

Overexpression of miR-150-5p Alleviates Apoptosis in Sepsis-Induced Myocardial Depression.

Sepsis-induced myocardial depression has high mortality and is very common in intensive care units. Previous studies have found that microRNAs play an important role in regulating sepsis-induced myocardial depression. miR-150-5p is involved in many biological processes; however, the mechanism underlying its role in sepsis-induced myocardial depression is still unclear. In this study, we generated rat models of septic shock induced by lipopolysaccharide. Whole genomic RNA sequencing was performed on 12 left ventricles collected after LPS treatment to identify miRNAs. Most of the target genes of the differently expressed microRNAs were involved in apoptosis, according to Gene Ontology. We also observed apoptosis in the heart tissue and in H9C2 cardiomyocytes stimulated with lipopolysaccharide, indicating that cell apoptosis may be an important mechanism in sepsis-induced myocardial depression. Furthermore, the expression of miR-150-5p was reduced, and overexpression of miR-150-5p with mimics resulted in a decrease in apoptosis, decreased expression of cleaved caspase3 and Bax, and increased expression of Bcl-2. Additionally, after H9C2 cells were transfected with miR-150-5p mimics or an inhibitor, the expression of Akt2 decreased or increased, respectively. These findings suggest that miR-150-5p can alleviate apoptosis and may be a novel therapeutic target for sepsis-induced myocardial depression.

Interferon Regulatory Factor-2 Binding Protein 2 Ameliorates Sepsis-Induced Cardiomyopathy via AMPK-Mediated Anti-Inflammation and Anti-Apoptosis.

Cardiomyopathy commonly occurs after sepsis and is closely associated with high mortality in clinic. Interferon regulatory factor-2 binding protein 2 (IRF2BP2) has been identified as a negative regulator of inflammation, but its role in septic cardiomyopathy is unknown. The current study aims to illuminate the regulatory function of IRF2BP2 on sepsis-induced cardiomyopathy and to explore the underlying mechanisms. Protein expression of IRF2BP2 in response to sepsis-induced cardiomyopathy was examined in the heart of mice challenged by LPS intraperitoneal injection. AAV9-delivered IRF2BP2 overexpression in the heart was applied to evaluate the regulatory role of IRF2BP2 in sepsis-induced myocardial depression, inflammatory response, and cell death. The molecular mechanisms underlying IRF2BP2-regulated cardiomyopathy were explored using western blot screening assay. Primary cardiomyocytes have been isolated to further confirm the role and mechanism of IRF2BP2 during septic cardiomyopathy. IRF2BP2 expression was dramatically increased in the heart of mice after LPS administration. AAV9-mediated IRF2BP2 overexpression significantly improved sepsis-induced cardiac dysfunction, inhibited inflammatory cell infiltration and cytokine production, and blocked cell death after LPS treatment. Mechanistically, IRF2BP2 activated AMPK signaling in cardiomyocytes, while inhibiting AMPK activation largely reversed IRF2BP2-benefited inflammatory suppression and cell survival. These findings clearly demonstrated that IRF2BP2 is a potent suppressor of sepsis-induced myocardial depression and related heart impairment. Targeting IRF2BP2 represents a promising therapeutic strategy for septic cardiomyopathy.

Combination of melatonin and irisin ameliorates lipopolysaccharide-induced cardiac dysfunction through suppressing the Mst1-JNK pathways.

Despite significant advances in therapies in past decades, the mortality rate of septic cardiomyopathy remains high. The aim of this study is to explore the therapeutic effects of combined treatment using melatonin and irisin in a mouse model of lipopolysaccharide (LPS)-mediated septic cardiomyopathy. Our data found that melatonin and irisin could further attenuate LPS-induced myocardial depression. Molecular investigation illustrated that melatonin and irisin cotreatment sustained cardiomyocyte viability and improved mitochondrial function under LPS stress. Pathway analysis demonstrated that macrophage-stimulating 1 (Mst1), which was significantly activated by LPS, was drastically inhibited by melatonin/irisin cotreatment. Mechanically, Mst1 activated c-Jun N-terminal kinase (JNK) pathway and the latter induced oxidative stress, adenosine triphosphate metabolism disorder, mitochondrial membrane potential reduction, and cardiomyocyte death activation. Melatonin and irisin cotreatment effectively inhibited the Mst1-JNK pathway and, thus, promoted cardiomyocyte survival and mitochondrial homeostasis. Interestingly, Mst1 overexpression abolished the beneficial effects of melatonin and irisin in vivo and in vitro. Altogether, our results confirmed that melatonin and irisin combination treatment could protect heart against sepsis-induced myocardial depression via modulating the Mst1-JNK pathways.

Characterization of Long Noncoding RNA and mRNA Profiles in Sepsis-Induced Myocardial Depression

Septic shock with heart dysfunction is very common in intensive care units. However, whether long noncoding RNA (lncRNA) and mRNA profiles differ between patients with and without myocardial depression is unknown. We generated rat models of hypodynamic septic shock induced by lipopolysaccharide. A total of 12 rat models was constructed and heart tissue from each was collected. Whole genomic RNA sequencing was performed on left ventricular tissue; 6,508 novel lncRNAs and 432 annotated lncRNAs were identified in heart samples, and 74 lncRNAs were expressed differently in the sepsis and control groups. Gene ontology term enrichment indicated apoptosis and its related pathways showed obvious enrichment, which suggested cell apoptosis could play a critical role in the process of myocardial depression. Furthermore, we focused on one lncRNA from the Pvt1 gene. By silencing this lncRNA, we demonstrated knockdown of Pvt1 expression could induce cell apoptosis in lipopolysaccharide-induced heart cells, through increasing the expression of c-Myc, Bid, Bax, and caspase-3 and decreasing the expression of Myd88 and Bcl-2, thereby proving its functional role in myocardial depression. These results demonstrate that lncRNAs both participate in and mediate the pathological process of myocardial depression. Our study improves the understanding of the basic molecular mechanisms underlying myocardial depression.

Characterization of Circular RNA and microRNA Profiles in Septic Myocardial Depression: a Lipopolysaccharide-Induced Rat Septic Shock Model.

Septic shock with heart dysfunction is common in intensive care units. However, the mechanism underlying myocardial depression is still unclear. Whether circular RNA (circRNA) or microRNA (miRNA) profiles differ between patients with and without myocardial depression is unknown. We generated a hypodynamic septic shock model induced by lipopolysaccharide (LPS) in adolescent rats. A total of 12 rats were utilized and heart tissue from each was collected. RNA sequencing was performed on left ventricular tissue. We focused on features of circRNAs and miRNAs, predicting their function by bioinformatic analysis and constructing circRNA-associated and miRNA-associated regulatory networks in heart tissue. We detected 851 circRNAs in heart samples, and 11 showed differential expression. A total of 639 annotated miRNAs and 91 novel miRNAs were explored including 78 showing differential expression between the two groups. We then constructed the most comprehensive circRNA-associated and miRNA-associated networks to explore their regulatory relationship in septic heart tissue, and demonstrated that different networks could potentially participate in and regulate the pathological process of sepsis. Furthermore, gene ontology term enrichment indicated miRNAs, and miRNA-mRNA networks could be associated with regulation and metabolic process, or influence cellular functions. The construction of regulator networks could improve the understanding of the basic molecular mechanisms underlying myocardial depression. It will be important for future investigations to ascertain the biological mechanisms present during the development of sepsis-induced myocardial depression to influence approaches to treatment.

Irisin ameliorates septic cardiomyopathy via inhibiting DRP1-related mitochondrial fission and normalizing the JNK-LATS2 signaling pathway.

Irisin plays a protective effect in acute and chronic myocardial damage, but its role in septic cardiomyopathy is unclear. The aim of our study was to explore the in vivo and in vitro effects of irisin using an LPS-induced septic cardiomyopathy model. Our results demonstrated that irisin treatment attenuated LPS-mediated cardiomyocyte death and myocardial dysfunction. At the molecular level, LPS application was associated with mitochondrial oxidative injury, cardiomyocyte ATP depletion and caspase-related apoptosis activation. In contrast, the irisin treatment sustained mitochondrial function by inhibiting DRP1-related mitochondrial fission and the reactivation of mitochondrial fission impaired the protective action of irisin on inflammation-attacked mitochondria and cardiomyocytes. Additionally, we found that irisin modulated DRP1-related mitochondrial fission through the JNK-LATS2 signaling pathway. JNK activation and/or LATS2 overexpression abolished the beneficial effects of irisin on LPS-mediated mitochondrial stress and cardiomyocyte death. Altogether, our results illustrate that LPS-mediated activation of DRP1-related mitochondrial fission through the JNK-LATS2 pathway participates in the pathogenesis of septic cardiomyopathy. Irisin could be used in the future as an effective therapy for sepsis-induced myocardial depression because it corrects DRP1-related mitochondrial fission and normalizes the JNK-LATS2 signaling pathway.

The down-regulation of cardiac contractile proteins underlies myocardial depression during sepsis and is mitigated by carbon monoxide

The aim of this study is to investigate the mechanism underling cardiac dysfunction during sepsis, as well as the possible amelioration of this dysfunction by exogenous carbon monoxide (CO) administration. For this purpose, rats (six-week-old, male, Sprague-Dawley) were administered LPS (15 mg/kg body weight, i.p. 6 h) and/or CORM (30 mg/kg, i.p.). The decreased left ventricular ejection fraction (EF) observed in LPS group rats was recovered in the LSP + CORM group, confirming the protective role of CO against sepsis-induced myocardial depression. Proteomic as well as immunoblot analysis showed that the levels of myosin heavy and light chains (MHC and MLC) as well as α-cardiac actin (ACTC) were decreased in the LPS group, and these decreases were mitigated in the LSP + CORM group, suggesting that the amounts of major contractile proteins are decreased in depressed myocardium. Not only LPS-induced inflammatory cytokine (TNFα and IL-1β) production but also the decrease in myofilament proteins was mitigated by CORM. These results confirm the protective action of exogenously administered CO against myocardial depression during sepsis, and reveal a novel mechanism underling cardiac dysfunction during sepsis.

An experimental study of the protective effect of simvastatin on sepsis-induced myocardial depression in rats

Many patients with sepsis died of heart failure caused by sepsis-induced myocardial depression. Patients with cardiovascular diseases treated by statins have a lower incidence and mortality of sepsis, although the mechanisms remain elusive. To investigate the protective effect of simvastatin on sepsis-induced myocardial depression and to explore possible mechanisms of action. Thirty six adult male Wistar rats were pretreated with simvastatin (0.2μg/g, q12h) for one week before cecal ligation and puncture (CLP). It was found that in simvastatin-treated rats, cardiac function indices, including left ventricular systolic pressure (LVESP) and maximal rate of rise and fall of left ventricular pressure (±dp/dtmax) and mean arterial pressure(MAP) markedly improved. Myocardial cells examined with hematoxylin and eosin (HE) were only partially swollen and degenerated and with fewer inflammatory cells infiltrating. Expressions of TLR4 and NF-κB p65 protein were significantly lower in simvastatin-treated rats than that in sepsis rats at the same time point. Levels of TNF-α, IL-1β, IL-6, MCP-1 and NO in myocardial tissues, together with levels of CTnI in serum were significantly declined in simvastatin-treated rats. Simvastatin has a protective effect on myocardial depression caused by sepsis. The effect may be mediated by the inhibition of TLR4-NF-κB signaling pathway, which leads to reduced levels of downstream inflammatory factors such as TNF-α, IL-1β, IL-6, MCP-1 and NO.

NT-proBNP correlates with the illness scores pneumonia severity index and CURB-65 in patients with pneumonia

&lt;em&gt;Pneumonia severity index&lt;/em&gt; (PSI) and CURB-65 (&lt;em&gt;confusion, urea, respiratory rate, blood pressure, age ≥65&lt;/em&gt;) are used to estimate the severity and prognosis of patients with pneumonia. NT-proBNP is a marker of myocardial stress and of sepsis-induced myocardial depression and might be used to predict short and long-term survival in patients with pneumonia. Twenty-three patients [age 79±15 standard deviation (SD); M/F 8/15, CURB-65 2.2±0.9 SD, PSI 118±38 SD, procalcitonin 3.9±5 SD] with pneumonia hospitalized in our Internal Medicine Unit were retrospectively evaluated. NT-proBNP was measured in the first 72 h of hospitalization. CURB-65 and PSI were calculated and correlation with biomarkers investigated. NT-proBNP showed a moderate statistically significant correlation with both PSI and CURB-65 (NT-proBNP &lt;em&gt;vs&lt;/em&gt; PSI, r=0.42, P&amp;lt;0.05, NT-proBNP &lt;em&gt;vs&lt;/em&gt; CURB-65, r=0.46, P&amp;lt;0.05). These correlations were confirmed also when patients with a diagnosis of heart failure where excluded from the analysis, even if the correlation did not reach the statistical significance. NT-proBNP seems to well correlate with the illness scores PSI and CURB-65 and might be a reliable predictor of severity and survival in patients with pneumonia.

MicroRNA-135a is up-regulated and aggravates myocardial depression in sepsis via regulating p38 MAPK/NF-κB pathway

MicroRNA-135a (miR-135a) is implicated in the pathological processes of several cancers. However, the roles and regulatory mechanism of miR-135a in sepsis-induced myocardial depression (MD) remain largely unknown. In this study, the serum of patients with sepsis and healthy controls was obtained. The miR-135a expression was then measured. Then lentiviruses (miR-135a mimic, inhibitor and scramble control) were transfected into BALB/c mice. After 4days of transfection, polymicrobial sepsis model was established by cecal ligation and puncture (CLP) surgery. The serum tumor-necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6 were detected. Cardiac function was assessed. In addition, the protein expressions of p38 MAPK/NF-κB pathway-related proteins were determined. Besides, SB203580 and JSH-23, the inhibitors of p38 MAPK and NF-κB respectively, were used to treat the isolated ventricular myocytes in vitro. MiR-135a was significantly up-regulated in the serum of patients with sepsis. In comparison with CLP group, the concentrations of TNF-α, IL-1β and IL-6 and the expressions of p-p38 and p-p65 in CLP+miR-135a mimic group were significantly increased, while markedly decreased in CLP+miR-135a inhibitor group. Moreover, EF, FS, LVdP/dt (max), LVdP/dt (min) and LVDP of CLP+miR-135a mimic group were all significantly decreased, while markedly increased in CLP+miR-135a inhibitor group. Besides, the increased expressions of p-p38 and p-p65, decreased expression of p-IKBα and the decreased percentage of contraction amplitude in miR-135a mimic group were markedly reversed by SB203580 or JSH-23 treatments. Up-regulation of miR-135a could aggravate sepsis-induced inflammation and myocardial dysfunction via activation of p38 MAPK/NF-κB pathway.

Continuous blood purification treatment for sepsis-induced myocardial depression in pigs

Continuous blood purification treatment for sepsis-induced myocardial depression in pigs