Effect of inflammatory mediators on cardiovascular function:

Effects of biodegradable biomedical porous MnO2 nanoparticles on blood components and functions

In recent years, manganese dioxide (MnO₂) nanoparticles with unique physicochemical properties have been widely used in many biomedical fields, such as biosensors, contrast agents, tumor therapy, and drug delivery. From these applications, MnO₂ nanoparticles have great clinical translation potential. However, by contrast, the in vitro and in vivo biosafety of MnO₂ nanoparticles have been deeply and thoroughly clarified for the clinical translation, which hinders their clinical applications. In this work, we deeply investigated the blood safety of MnO₂ nanoparticles by conducting a series of in vitro and in vivo experiments. These included the effects of MnO₂ nanoparticles on morphology of red blood cells, activation of platelets, coagulation functions, and toxicity of key organs. The obtained results show that these effects displayed a concentration-dependent manner of MnO₂ nanoparticles. Different safe concentration ranges could be found in the different experimental index. This study provides important guidance for the specific biomedical applications of MnO₂ nanoparticles, greatly accelerating their laboratory development and clinical translation.

Sufentanil ameliorates oxygen‑glucose deprivation/reoxygenation‑induced endothelial barrier dysfunction in HCMECs via the PI3K/Akt signaling pathway

Ischemic heart disease, a chronic myocardial damage disease caused by coronary artery ischemia, is the leading cause of death worldwide. The aim of the present study was to explore the efficacy of sufentanil in myocardial ischemia/reperfusion (I/R) injury. Oxygen and glucose deprivation/reoxygenation (OGD/R) was utilized to induce human cardiac microvascular endothelial cells (HCMECs) to simulate myocardial I/R injury in vitro. The Cell Counting Kit-8 assay was used to detect the effects of sufentanil on HCMECs and OGD/R-induced HCMECs. The TUNEL, lactate dehydrogenase (LDH) activity, immunofluorescence and in vitro permeability assays, were used to assess apoptosis, LDH activity, VE-cadherin protein expression levels and endothelial barrier function in OGD/R-induced HCMECs, respectively. Moreover, western blotting was performed to assess the protein expression levels of apoptosis, endothelial barrier function and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)-related proteins. The results demonstrated that sufentanil had no significant influence on the viability of HCMECs but increased the viability of OGD/R-induced HCMECs in a dose-dependent manner. Furthermore, sufentanil inhibited cell apoptosis and permeability of OGD/R-induced HCMECs but enhanced the protein expression levels of tight junction proteins, including ZO-1, Occludin, VE-cadherin and Claudin-5. Sufentanil was also demonstrated to activate the PI3K/Akt signaling pathway. In addition, the use of LY294002, an inhibitor of the PI3K/Akt signaling pathway, partially abolished the protective effects of sufentanil on apoptosis, permeability and tight junction protein expression levels. These results indicated that sufentanil ameliorated OGD/R-induced endothelial barrier dysfunction in HCMECs, potentially via the PI3K/Akt signaling pathway. The present study therefore suggested that sufentanil may serve as a novel therapeutic option for the improvement of myocardial I/R injury.

Anesthesia Considerations in Infective Endocarditis

The management of infective endocarditis is complex and inherently requires multidisciplinary cooperation. About half of all patients diagnosed with infective endocarditis will meet the criteria to undergo cardiac surgery, which regularly takes place in urgent or emergency settings. The pathophysiology and clinical presentation of infective endocarditis make it a unique disorder within cardiac surgery that warrants a thorough understanding of specific characteristics in the perioperative period. This includes, among others, echocardiography, coagulation, bleeding management, or treatment of organ dysfunction. In this narrative review article, the authors summarize the current knowledge on infective endocarditis relevant for the clinical anesthesiologist in perioperative management of respective patients. Furthermore, the authors advocate for the anesthesiologist to become a structural member of the endocarditis team.

Susceptibility to COVID-19 in populations with health disparities: Posited involvement of mitochondrial disorder, socioeconomic stress, and pollutants

SARS-CoV-2 is a novel betacoronavirus that has caused the global health crisis known as COVID-19. The implications of mitochondrial dysfunction with COVID-19 are discussed as well as deregulated mitochondria and inter-organelle functions as a posited comorbidity enhancing detrimental outcomes. Many environmental chemicals (ECs) and endocrine-disrupting chemicals can do damage to mitochondria and cause mitochondrial dysfunction. During infection, SARS-CoV-2 via its binding target ACE2 and TMPRSS2 can disrupt mitochondrial function. Viral genomic RNA and structural proteins may also affect the normal function of the mitochondria-endoplasmic reticulum-Golgi apparatus. Drugs considered for treatment of COVID-19 should consider effects on organelles including mitochondria functions. Mitochondrial self-balance and clearance via mitophagy are important in SARS-CoV-2 infection, which indicate monitoring and protection of mitochondria against SARS-CoV-2 are important. Mitochondrial metabolomic analysis may provide new indicators of COVID-19 prognosis. A better understanding of the role of mitochondria during SARS-CoV-2 infection may help to improve intervention therapies and better protect mitochondrial disease patients from pathogens as well as people living with poor nutrition and elevated levels of socioeconomic stress and ECs.

Effects of ZIF-8 MOFs on structure and function of blood components

ZIF-8 MOFs, with their large specific surface area and void volume, unique biodegradability and pH sensitivity, and significant loading capacity, have been widely used as carrier materials for bioactive molecules such as drugs, vaccines and genes.

NCF2, MYO1F, S1PR4, and FCN1 as potential noninvasive diagnostic biomarkers in patients with obstructive coronary artery: A weighted gene co-expression network analysis

This study aims to explore the predictive noninvasive biomarker for obstructive coronary artery disease (CAD). By using the data set GSE90074, weighted gene co-expression network analysis (WGCNA), and protein-protein interactive network, construction of differentially expressed genes in peripheral blood mononuclear cells was conducted to identify the most significant gene clusters associated with obstructive CAD. Univariate and multivariate stepwise logistic regression analyses and receiver operating characteristic analysis were used to predicate the diagnostic accuracy of biomarker candidates in the detection of obstructive CAD. Furthermore, functional prediction of candidate gene biomarkers was further confirmed in ST-segment elevation myocardial infarction (STEMI) patients or stable CAD patients by using the datasets of GSE62646 and GSE59867. We found that the blue module discriminated by WGCNA contained 13 hub-genes that could be independent risk factors for obstructive CAD (P < .05). Among these 13 hub-genes, a four-gene signature including neutrophil cytosol factor 2 (NCF2, P = .025), myosin-If (MYO1F, P = .001), sphingosine-1-phosphate receptor 4 (S1PR4, P = .015), and ficolin-1 (FCN1, P = .012) alone or combined with two risk factors (male sex and hyperlipidemia) may represent potential diagnostic biomarkers in obstructive CAD. Furthermore, the messenger RNA levels of NCF2, MYO1F, S1PR4, and FCN1 were higher in STEMI patients than that in stable CAD patients, although S1PR4 showed no statistical difference (P > .05). This four-gene signature could also act as a prognostic biomarker to discriminate STEMI patients from stable CAD patients. These findings suggest a four-gene signature (NCF2, MYO1F, S1PR4, and FCN1) alone or combined with two risk factors (male sex and hyperlipidemia) as a promising prognostic biomarker in the diagnosis of STEMI. Well-designed cohort studies should be implemented to warrant the diagnostic value of these genes in clinical purpose.

Aortic cross-clamp time and cardiopulmonary bypass time: prognostic implications in patients operated on for infective endocarditis

OBJECTIVES

Prolonged aortic cross-clamp (XCT) and cardiopulmonary bypass time (CPBT) are associated with increased morbidity and mortality following cardiac surgery. The aim of this study was to assess the predictors of mortality and other severe postoperative complications in patients undergoing surgery for infective endocarditis (IE), focusing in particular on the role of prolonged XCT and CPBT.

METHODS

A retrospective single-centre study was conducted from January 2000 to January 2017, including all patients undergoing valvular surgery for IE. The primary end point was early postoperative mortality. The main secondary end point was a composite end point for severe postoperative complications.

RESULTS

During the study period, 264 patients were included. Early postoperative mortality was 14%. Prolonged CPBT [odds ratio (OR) 1.008, 95% confidence intervals (CIs) 1.003-1.01; P = 0.009] and increasing age (OR 1.04, 95% CI 1.01-1.07; P = 0.02) independently predicted mortality, while an inverse association was observed for left ventricular ejection fraction (OR 0.93, 95% CI 0.89-0.97; P = 0.0007). The best mortality cut-offs were >72 min for XCT and >166 min for CPBT. Prolonged CPBT also predicted severe complications, along with age, stroke, preoperative mechanical ventilation and reduced left ventricular ejection fraction. When XCT was included in the multivariable models instead of CPBT, it was associated with both mortality and severe complications.

CONCLUSIONS

Prolonged XCT and CPBT are associated with mortality and development of severe complications after valvular surgery for IE. Further validation of safe limits for XCT and CPBT might provide novel insights on how to improve intraoperative and postoperative outcomes of patients with IE.

MicroRNA-155 attenuates late sepsis-induced cardiac dysfunction through JNK and β-arrestin 2

Cardiac dysfunction is correlated with detrimental prognosis of sepsis and contributes to a high risk of mortality. After an initial hyperinflammatory reaction, most patients enter a protracted state of immunosuppression (late sepsis) that alters both innate and adaptive immunity. The changes of cardiac function in late sepsis are not yet known. MicroRNA-155 (miR-155) is previously found to play important roles in both regulations of immune activation and cardiac function. In this study, C57BL/6 mice were operated to develop into early and late sepsis phases, and miR-155 mimic was injected through the tail vein 48 h after cecal ligation and puncture (CLP). The effect of miR-155 on CLP-induced cardiac dysfunction was explored in late sepsis. We found that increased expression of miR-155 in the myocardium protected against cardiac dysfunction in late sepsis evidenced by attenuating sepsis-reduced cardiac output and enhancing left ventricular systolic function. We also observed that miR-155 markedly reduced the infiltration of macrophages and neutrophils into the myocardium and attenuated the inflammatory response via suppression of JNK signaling pathway. Moreover, overexpression of β-arrestin 2 (Arrb2) exacerbated the mice mortality and immunosuppression in late sepsis. Furthermore, transfection of miR-155 mimic reduced Arrb2 expression, and then restored immunocompetence and improved survival in late septic mice. We conclude that increased miR-155 expression through systemic administration of miR-155 mimic attenuates cardiac dysfunction and improves late sepsis survival by targeting JNK associated inflammatory signaling and Arrb2 mediated immunosuppression.

[Prognostic relevance of tissue oxygen saturation in patients in the early stage of multiple organ dysfunction syndrome]

BACKGROUND

Patients in circulatory shock exhibit insufficient peripheral perfusion to ensure adequate oxygenation of vital organs such as the heart and brain. Early detection of reduced tissue oxygen saturation (S_tO₂) could be used for rapid therapeutic intervention and thus improve the prognosis of patients in the early stage of multiple organ dysfunction syndrome (MODS).

MATERIALS AND METHODS

A total of 60 patients in the early stage of MODS (APACHE [Acute Physiology and Chronic Health Evaluation] II score ≥20) were investigated in a monocentric, prospective, randomized phase II study. S_tO₂ was measured using the InSpectraTM S_tO₂ system and compared with known indicators of hypoxia (peripheral oxygen saturation [S_pO₂], arterial oxygen saturation [S_aO₂], central venous oxygen saturation [S_cvO₂], pH, serum lactate). Clinical endpoints of the study were 28-day and 6‑month mortality as well as the need for invasive mechanical ventilation and renal replacement therapy during the hospital stay, respectively.

RESULTS

An increased 28-day and 6‑month mortality is found for patients with S_tO₂ <75% in contrast to patients with S_tO₂ ≥75%. Correlations of S_tO₂ with S_pO₂, S_cvO₂, and serum lactate are confirmed. Patients with reduced S_tO₂ tend to show a higher disease severity as measured by APACHE II score.

CONCLUSION

S_tO₂ shows prognostic relevance in patients at the early stage of MODS. Thus, the rapid and noninvasive assessment of S_tO₂ could be useful in risk stratification of these patients.

Formation of a TBX20-CASZ1 protein complex is protective against dilated cardiomyopathy and critical for cardiac homeostasis

By the age of 40, one in five adults without symptoms of cardiovascular disease are at risk for developing congestive heart failure. Within this population, dilated cardiomyopathy (DCM) remains one of the leading causes of disease and death, with nearly half of cases genetically determined. Though genetic and high throughput sequencing-based approaches have identified sporadic and inherited mutations in a multitude of genes implicated in cardiomyopathy, how combinations of asymptomatic mutations lead to cardiac failure remains a mystery. Since a number of studies have implicated mutations of the transcription factor TBX20 in congenital heart diseases, we investigated the underlying mechanisms, using an unbiased systems-based screen to identify novel, cardiac-specific binding partners. We demonstrated that TBX20 physically and genetically interacts with the essential transcription factor CASZ1. This interaction is required for survival, as mice heterozygous for both Tbx20 and Casz1 die post-natally as a result of DCM. A Tbx20 mutation associated with human familial DCM sterically interferes with the TBX20-CASZ1 interaction and provides a physical basis for how this human mutation disrupts normal cardiac function. Finally, we employed quantitative proteomic analyses to define the molecular pathways mis-regulated upon disruption of this novel complex. Collectively, our proteomic, biochemical, genetic, and structural studies suggest that the physical interaction between TBX20 and CASZ1 is required for cardiac homeostasis, and further, that reduction or loss of this critical interaction leads to DCM. This work provides strong evidence that DCM can be inherited through a digenic mechanism.

A molecular understanding of cardiomyocyte development is an essential goal for improving clinical approaches to CHD. While TBX20 is an essential transcription factor for heart development and its disease relevance is well established, many fundamental questions remain about the mechanism of TBX20 function. Principle among these is how TBX20 mutations associated with adult dilated cardiomyopathy circumvent (DCM) the essential embryonic requirement for TBX20 in heart development. Here we report using an integrated approach that TBX20 complexes with the cardiac transcription factor CASZ1 in vivo. We confirmed TBX20 and CASZ1 interact biochemically and genetically, and show mice heterozygous for both Tbx20 and Casz1 die, beginning at 4 to 8 weeks post birth, exhibiting hallmarks of DCM. Interestingly, the human mutant TBX20^F256I bypasses the early essential requirement for TBX20 but leads to DCM. We report here that TBX20^F256I disrupts the TBX20-CASZ1 interaction, ascribing clinical relevance to this protein complex. Further, by using quantitative proteomics we have identified the molecular pathways altered in TBX20-CASZ1-mediated DCM. Together, these results identify a novel interaction between TBX20 and CASZ1 that is essential for maintaining cardiac homeostasis and imply that DCM can be inherited through a digenic mechanism.

Cardiovascular dysfunction in sepsis at the dawn of emerging mediators

Subcellular dysfunction and impaired metabolism derived from the complex interaction of cytokines and mediators with cellular involvement are on the basis of the cardiovascular response to sepsis. The lethal consequences of an infection are intimately related to its ability to spread to other organ sites and the immune system of the host. About one century ago, William Osler (1849-1919), a Canadian physician, remarkably defined the sequelae of the host response in sepsis: "except on few occasions, the patient appears to die from the body's response to infection rather than from it." Cardiac dysfunction has received considerable attention to explain the heart failure in patients progressing from infection to sepsis, but our understanding of the processes remains limited. In fact, most concepts are linked to a mechanical concept of the sarcomeric structure, and physiological data seems to be often disconnected. Cytokines, prostanoids, and nitric oxide release are high direct impact factors, but coronary circulation and cardiomyocyte physiology also play a prominent role in modulating the effects of monocyte adhesion and infiltration. Damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs) are involved in the host response. The identification of microRNAs, as well as the cyclic activation of the inflammatory cascade, has further added complexity to the scene. In this review, we delineate the current concepts of cellular dysfunction of the cardiomyocyte in the setting of sepsis and consider potential therapeutic strategies.

Plasma cholesterol homeostasis, HDL remodeling and function during the acute phase reaction

Acute phase reaction (APR) is a systemic inflammation triggered by several conditions associated with lipid profile alterations. We evaluated whether APR also associates with changes in cholesterol synthesis and absorption, HDL structure, composition, and cholesterol efflux capacity (CEC). We analyzed 59 subjects with APR related to infections, oncologic causes, or autoimmune diseases and 39 controls. We detected no difference in markers of cholesterol synthesis and absorption. Conversely, a significant reduction of LpA-I- and LpAI:AII-containing HDL (-28% and -44.8%, respectively) and of medium-sized HDL (-10.5%) occurred in APR. Total HDL CEC was impaired in APR subjects (-18%). Evaluating specific CEC pathways, we found significant reductions in CEC by aqueous diffusion and by the transporters scavenger receptor B-I and ABCG1 (-25.5, -41.1 and -30.4%, respectively). ABCA1-mediated CEC was not affected. Analyses adjusted for age and gender provided similar results. In addition, correcting for HDL-cholesterol (HDL-C) levels, the differences in aqueous diffusion total and ABCG1-CEC remained significant. APR subjects displayed higher levels of HDL serum amyloid A (+20-folds; P = 0.003). In conclusion, APR does not associate with cholesterol synthesis and absorption changes but with alterations of HDL composition and a marked impairment of HDL CEC, partly independent of HDL-C serum level reduction.