Anti-TNF-α therapy for patients with sepsis: a systematic meta-analysis

Deciphering the role of cytokines in aging: Biomarker potential and effective targeting

Aging is often characterized by chronic inflammation, immune system dysregulation, and cellular senescence with chronically elevated levels of pro-inflammatory cytokines. These small glycoproteins are mainly secreted by immune cells, mediating intercellular communication and immune system modulation through inflammatory signaling. Their pro- and anti-inflammatory effects make them a noteworthy research topic as well as a promising ally in combating inflammation and the aging process. Cytokines exert a synergistic role in aging and disease and may prove useful biomarkers of tissue-specific dysregulation, disease diagnosis and monitoring, presenting potential therapeutic options as anti-inflammatory and senolytic medications. In this review, we address the cellular and molecular mechanisms implicating cytokines in the aging process and related diseases, highlighting their biomarker potential. We focus on the current therapeutic strategies, including specific pharmaceutical agents, supplements, a balanced diet, and healthy habits such as exercise, stress management, and caloric restriction.

Clinical efficacy of oXiris-continuous hemofiltration adsorption in septic shock patients: A retrospective analysis

OBJECTIVE

This study aimed to assess the clinical impact of oXiris-continuous hemofiltration adsorption on patients with septic shock and their prognosis.

DESIGN

A retrospective study.

PARTICIPANTS

Septic shock patients.

INTERVENTIONS

The oXiris group underwent hemofiltration adsorption using oXiris hemofilters and septic shock standard treatment, while the control group received septic shock standard treatment.

MAIN VARIABLES OF INTEREST

The changes in inflammatory indicators and short-term mortality rate were evaluated. Propensity score matching (PSM) was conducted based on the 1:2 ratio between the oXiris and control groups to account for any baseline data differences.

RESULTS

Results showed that after 24 h, 48 h, and 72 h of treatment, PCT, IL-6, and hs-CRP levels in the oXiris group were significantly lower than those in the control group (P < 0.05). However, there were no significant differences in norepinephrine equivalents and organ function status (APACHE II score, SOFA score, Lac) between the two groups at the same time points. The 72-h mortality rate (21.88% vs. 34.04%) and the 7-day mortality rate (28.12% vs. 44.68%) were lower in the oXiris group compared to the control group, but not statistically significant. The 28-day mortality rate did not show a significant difference between the two groups (53.19% vs. 56.25%).

CONCLUSIONS

oXiris continuous hemofiltration adsorption technology may reduce the levels of inflammatory factors in patients with septic shock; however, it does not appear to enhance organ function or improve the 28-day mortality rate in these patients.

Emerging antimicrobial therapies for Gram-negative infections in human clinical use

The growing problem of multi-drug resistance (MDR) is prevalent in Gram-negative infections, and the significant decline in antibiotic development poses a critical threat to global public health. Many emerging non-antibiotic therapies have been proposed, including phage therapy, anti-virulence agents, antimicrobial peptides, plasmapheresis, and immunotherapy options. To identify the therapies most likely to be the next immediate step in treatment for MDR Gram-negative infections, this review highlights emerging therapeutics that have either been successfully used for compassionate care or are currently undergoing clinical trials.

Induction of PD-1 and CD44 in CD4+ T cells by circulatory extracellular vesicles from severe dengue patients drives endothelial damage via the NF-kB signaling pathway

Extracellular vesicles (EVs) emerged as critical contributors to the pathogenesis of vascular endothelial barrier dysfunction during the inflammatory response to infection. However, the contribution of circulating EVs to modifying endothelial function during dengue virus infection remains unclear. In this study, we showed that severe dengue patients' plasma-derived EV (SD-EV) were found to carry elevated levels of different protein cargos, e.g., immunoregulatory proteins (PD-L1, CD44). Further, we demonstrated that SD-EV induces PD-1 and CD44 expression on CD4+ T cells. SD-EV-modulated CD4+ T (SD-EV-CD4) cells released secretome delayed endothelial cell (EC) migration, arrested them in the G1 phase, and augmented the expression of PD-L1 and ICAM-1 expression on EC through the Notch signaling pathway. Blocking SD-EV and CD4+ T-cell interaction through the PD-1/PD-L1 pathway partially rescued the CD4+ T cell's effect on EC but did not alter ICAM-1 expression on EC. We observed that the ICAM-1 expression on EC and hyaluronic acid (HA) release from EC was mediated by CD44, which was elevated on SD-EV-modulated CD4+ T cells (SD-EV-CD4), indicating a permeability defect. Blocking of CD44 on SD-EV-CD4 significantly reduced ICAM-1 expression on EC. Further, depletion of specific cytokines, e.g., TNF-α and not IFN-γ from the SD-EV-CD4 secretome, reduced ICAM-1 expression, decreased transendothelial electrical resistance, and induced apoptosis on EC significantly. Treatment with NF-kB inhibitor before secretome addition to EC reduced ICAM-1 expression on EC. In conclusion, we provided evidence that SD-EV-CD4 carrying PD-1 and CD44, when interacting with EC, significantly affected endothelial cell properties and may be significant in dengue-mediated endothelial dysfunction.IMPORTANCEExtracellular vesicles (EVs) are small membrane vesicles secreted into biological fluids, including plasma from living cells, holding insights into pathological processes. Studying EVs under pathological conditions is extremely important as they play a selective role in intercellular communication and modulation of immune response under diverse pathological conditions. However, there is less clarity on how circulatory extracellular vesicles influence immune cells during dengue virus (DV) infection and impact pathogenesis. Our present study highlights the impact of severe dengue patients' plasma-derived EV (SD-EV) on CD4+ T cells and together induce endothelial barrier dysfunction. We provided evidence that SD-EV induces PD-1 and CD44 on CD4+ T cells and, when interacting with endothelial cells (EC), drives endothelial damage through direct interaction or secretome and may be significant in dengue-mediated endothelial dysfunction.

The Role of HMGB1 in Infection-Related Cognitive Deficits

Infectious diseases caused by fungi, viruses, or bacteria can have a profound impact on human cognition. This can be due to either direct spread to the central nervous system (CNS) or indirect neuroinflammation. Ultimately causing neuronal damage and even neurodegeneration. Deteriorations in cognition, such as poor encoding and attention deficits, have been reported secondary to infectious diseases. Preclinical studies have identified the underlying mechanisms of these infection-related cognitive effects, such as through blood-brain barrier (BBB) disruption and M1 microglial polarization. These mechanisms are spearheaded by inflammatory markers that are released/initiated by the pathogens over the course of the infection. Among them, the high mobility group box 1 (HMGB1) protein is a common biomarker implicated across several infection-related cognitive deficits. Understanding these effects and mechanisms is crucial for the development of strategies to prevent and treat infection-related cognitive impairment. This review will thus consolidate and elucidate the current knowledge on the potential role of HMGB1 as a therapeutic target for infection-related cognitive impairments. This review will not only advance scientific understanding but also have significant clinical and public health implications, especially considering recent global health challenges. Based on the selected articles, extracellular HMGB1, as opposed to intracellular HMGB1, acts as damage-associated molecular patterns (DAMPs) or alarmins when released in the peripheries secondary to inflammasome activation. Due to their low molecular weight, they then enter the CNS through routes such as retrograde transport along the afferent nerves, or simple diffusion across the impaired BBB. This results in further disruption of the brain microenvironment due to the dysregulation of other regulatory pathways. The outcome is structural neuronal changes and cognitive impairment. Given its key role in neuroinflammation, HMGB1 holds promise as both a biomarker for diagnostic detection and a potential therapeutic target candidate for preventing infection-related cognitive impairment.

Soluble CD72 concurrently impairs T cell functions while enhances inflammatory response in sepsis

BACKGROUND

Sepsis is defined as multi-organ dysfunction caused by dysregulated host response to infection. This dysregulated host response includes enhanced inflammatory responses and suppressed adaptive immunity, but the molecular mechanisms behind it have not yet been elucidated. CD72, a type II transmembrane protein that is primarily expressed in B cells, was found to play an immunomodulatory role in the immune system and was associated with mortality in patients with sepsis. However, whether CD72 affects the pathogenesis of sepsis by influencing the immune response remains unclear.

METHODS

We first collected peripheral blood from 40 healthy volunteers and 57 septic patients and analyzed the mRNA levels of CD72 and the expression of its soluble form sCD72 using Realtime-PCR and ELISA. We then employed the CRISPR/Cas9 system to generate CD72 knockout mice (CD72-KO) and established a cecal ligation and puncture (CLP) model to analyze the effects of CD72 gene deletion on the survival, organ injury and immune response of septic mice by Kaplan-Meier survival analysis, pathological sections and flow cytometry. We also observe the effects of excess sCD72 on survival and immune response in sepsis by injecting recombinant CD72 protein into mice. Finally, the mechanism of sCD72 affecting sepsis immunity was analyzed by fluorescence staining, confocal microscopy and flow cytometry.

RESULTS

We found that when sepsis occurs, the levels of CD72 mRNA and cell surface CD72 in immune cells decrease, while the level of soluble sCD72 in the blood increases significantly. Excessive sCD72 increased sepsis mortality in a dose-dependent manner, which can bind to CD100 on the surface of T cells and enter the cytoplasm, leading to impaired T cell functions, including a decrease in CD4+IFN-γ+, CD8+Perforin+, CD8+GZMB+, and CD8+FASL+ population and an increase in inflammatory CD4+TNF-α+ population, thereby suppressing adaptive immunity while enhancing inflammatory response.

CONCLUSION

The immunosuppression of sepsis has been recognized, but the underlying mechanism has not been fully elucidated. Our study identified for the first time that sCD72 is an important mediator that cause adaptive immunosuppression during sepsis, which leads to T cell suppression by competitively binding to CD100 on the surface of T cells. Our study provides novel insights in our understanding of sepsis-related immunosuppression and may provide translational opportunities for the design of new diagnostic biomarkers and therapeutic targets for sepsis.

Monocyte-Derived Macrophages Induce Alveolar Macrophages Death via TNF-α in Acute Lung Injury

INTRODUCTION

Acute lung injury (ALI) and its subsequent progression to acute respiratory distress syndrome (ARDS) are severe respiratory conditions. They are marked by rapid lung function deterioration and extensive pulmonary inflammation, often resulting in critical patient outcomes. Alveolar macrophages (AMs) and monocyte-derived macrophages (MDMs) are two distinct subsets of lung macrophages present in the alveoli during ALI. Both are critical mediators of pulmonary inflammation. Our study examined the interplay between AMs and MDMs in the inflammatory environment of ALI/ARDS.

METHODS

Mice were treated with lipopolysaccharide (LPS) to establish ALI models. The lung tissues of mice were subjected to hematoxylin-eosin staining to observe the degree of tissue damage. In vivo, CCR2-deficient mice or depleting peripheral blood mononuclear cells by clodronate liposomes were used to reduce MDMs recruitment. The bronchoalveolar lavage fluid (BALF) supernatants were used for cytokine and total protein analyses. AMs and MDMs in the BALF were analyzed by flow cytometry. The levels of AMs death were determined through propidium iodide staining and measured by flow cytometry. In vitro, primary AMs were exposed to MDM-conditioned medium or TNF-α, and their death levels were assessed under a fluorescence microscope with propidium iodide staining.

RESULTS

AMs significantly decrease in number and undergo extensive cell death during ALI. The reduced MDMs recruitment can increase the number of AMs, reduce AMs death, and alleviate lung injury. In vitro, MDM-conditioned medium can induce AMs death and TNF-α is one of the major secretions. It indicates that TNF-α stimulation in vitro promotes AMs death. In vivo, MDMs are identified as the primary cells secreting TNF-α. Additionally, the treatment with TNF-α antagonists can reduce AMs death and the severity of lung injury.

CONCLUSION

Our study demonstrates that MDMs contribute to AMs death during ALI through TNF-α. Targeting TNF-α may offer a therapeutic strategy to mitigate AMs death and lung injury in ALI/ARDS.

Regulation of plasma soluble receptors of TNF and IL-1 in patients with COVID-19 differs from that observed in sepsis

OBJECTIVES

IL-1α/β and TNF are closely linked to the pathology of severe COVID-19 and sepsis. The soluble forms of their receptors, functioning as decoy receptors, exhibit inhibitory effects. However, little is known about their regulation in severe bacterial and viral infections, which we aimed to investigate in this study.

METHODS

The circulating soluble receptors of TNF (sTNFR1 and sTNFR2) and IL-1α/β (sIL-1R1, sIL-1R2) were evaluated in the plasma of patients with COVID-19, severe bacterial infections, and sepsis and compared with healthy controls. Additionally, IL1R1, IL1R2, TNFRSF1A, and TNFRSF1B expression was evaluated at the single cell level in PBMCs derived from COVID-19 or sepsis patients.

RESULTS

Plasma concentrations of sIL-1R1, sTNFR1, and sTNFR2 were significantly higher in COVID-19 patients compared to healthy subjects. Notably, sIL-1R1 levels were particularly elevated in ICU COVID-19 patients, and transcriptome analysis indicated heightened IL1R1 expression in PBMCs from severe COVID-19 patients. In severe bacterial infections, only sTNFR1 and sTNFR2 exhibited increased levels compared to healthy controls. Sepsis patients had decreased sIL-1R1 plasma concentrations but elevated sIL-1R2, sTNFR1, and sTNFR2 levels compared to healthy individuals, reflecting the heightened expression due to the increased numbers of monocytes present in sepsis. Finally, elevated concentrations of sIL-1R2, sTNFR1, and sTNFR2 were moderately associated with reduced 28-day survival in sepsis patients.

CONCLUSION

Our study reveals distinct regulation of plasma concentrations of soluble IL-1 receptors in COVID-19 and sepsis. Moreover, soluble TNF receptors 1 and 2 consistently rise in all conditions and show a positive correlation with disease severity in sepsis.

Dichotomous outcomes of TNFR1 and TNFR2 signaling in NK cell-mediated immune responses during inflammation

Natural killer (NK) cell function is regulated by a balance of activating and inhibitory signals. Tumor necrosis factor (TNF) is an inflammatory cytokine ubiquitous across homeostasis and disease, yet its role in regulation of NK cells remains unclear. Here, we find upregulation of the immune checkpoint protein, T cell immunoglobulin and mucin domain 3 (Tim3), is a biomarker of TNF signaling in NK cells during Salmonella Typhimurium infection. In mice with conditional deficiency of either TNF receptor 1 (TNFR1) or TNF receptor 2 (TNFR2) in NK cells, we find TNFR1 limits bacterial clearance whereas TNFR2 promotes it. Mechanistically, via single cell RNA sequencing we find that both TNFR1 and TNFR2 induce the upregulation of Tim3, while TNFR1 accelerates NK cell death but TNFR2 promotes NK cell accumulation and effector function. Our study thus highlights the complex interplay of TNF-based regulation of NK cells by the two TNF receptors during inflammation.

Paneth cell TNF signaling induces gut bacterial translocation and sepsis

The cytokine tumor necrosis factor (TNF) plays important roles in limiting infection but is also linked to sepsis. The mechanisms underlying these paradoxical roles are unclear. Here, we show that TNF limits the antimicrobial activity of Paneth cells (PCs), causing bacterial translocation from the gut to various organs. This TNF-induced lethality does not occur in mice with a PC-specific deletion in the TNF receptor, P55. In PCs, TNF stimulates the IFN pathway and ablates the steady-state unfolded protein response (UPR), effects not observed in mice lacking P55 or IFNAR1. TNF triggers the transcriptional downregulation of IRE1 key genes Ern1 and Ern2, which are key mediators of the UPR. This UPR deficiency causes a significant reduction in antimicrobial peptide production and PC antimicrobial activity, causing bacterial translocation to organs and subsequent polymicrobial sepsis, organ failure, and death. This study highlights the roles of PCs in bacterial control and therapeutic targets for sepsis.

Rapid high-throughput method for investigating physiological regulation of neutrophil extracellular trap formation

BACKGROUND

Neutrophils, the most abundant white blood cells in humans, play pivotal roles in innate immunity, rapidly migrating to sites of infection and inflammation to phagocytose, neutralize, and eliminate invading pathogens. Neutrophil extracellular trap (NET) formation is increasingly recognized as an essential rapid innate immune response, but when dysregulated, it contributes to pathogenesis of sepsis and immunothrombotic disease.

OBJECTIVES

Current NETosis models are limited, routinely employing nonphysiological triggers that can bypass natural NET regulatory pathways. Models utilizing isolated neutrophils and immortalized cell lines do not reflect the complex biology underlying neutrophil activation and NETosis that occurs in whole blood. To our knowledge, we report the first human ex vivo model utilizing naturally occurring molecules to induce NETosis in whole blood. This approach could be used for drug screening and, importantly, inadvertent activators of NETosis.

METHODS

Here we describe a novel, high-throughput ex vivo whole blood-induced NETosis model using combinatorial pooling of native NETosis-inducing factors in a more biologically relevant Synthetic-Sepsis model.

RESULTS

We found different combinations of factors evoked distinct neutrophil responses in the rate of NET generation and/or magnitude of NETosis. Despite interdonor variability, similar sets of proinflammatory molecules induced consistent responses across donors. We found that at least 3 biological triggers were necessary to induce NETosis in our system including either tumor necrosis factor-α or lymphotoxin-α.

CONCLUSION

These findings emphasize the importance of investigating neutrophil physiology in a biologically relevant context to enable a better understanding of disease pathology, risk factors, and therapeutic targets, potentially providing novel strategies for disease intervention and treatment.

The role of trained immunity in sepsis

Sepsis is defined as a life-threatening organ dysfunction syndrome caused by dysregulated host response to infection, characterized by a systemic inflammatory response to infection. The use of antibiotics, fluid resuscitation, and organ support therapy has limited prognostic benefit in patients with sepsis, and its incidence is not diminishing, which is attracting increased attention in medicine. Sepsis remains one of the most debilitating and expensive illnesses. One of the main reasons of septic mortality is now understood to be disruption of immune homeostasis. Immunotherapy is revolutionizing the treatment of illnesses in which dysregulated immune responses play a significant role. This "trained immunity", which is a potent defense against infection regardless of the type of bacteria, fungus, or virus, is attributed to the discovery that the innate immune cells possess immune memory via metabolic and epigenetic reprogramming. Here we reviewed the immunotherapy of innate immune cells in sepsis, the features of trained immunity, and the relationship between trained immunity and sepsis.

Current perspectives in the management of sepsis and septic shock

Within patients with sepsis, there exists significant heterogeneity, and while all patients should receive conventional therapy, there are subgroups of patients who may benefit from specific therapies, often referred to as rescue therapies. Therefore, the identification of these specific patient subgroups is crucial and lays the groundwork for the application of precision medicine based on the development of targeted interventions. Over the years, efforts have been made to categorize sepsis into different subtypes based on clinical characteristics, biomarkers, or underlying mechanisms. For example, sepsis can be stratified into different phenotypes based on the predominant dysregulated host response. These phenotypes can range from hyperinflammatory states to immunosuppressive states and even mixed phenotypes. Each phenotype may require different therapeutic approaches to improve patient outcomes. Rescue strategies for septic shock may encompass various interventions, such as immunomodulatory therapies, extracorporeal support (e.g., ECMO), or therapies targeted at specific molecular or cellular pathways involved in the pathophysiology of sepsis. In recent years, there has been growing interest in precision medicine approaches to sepsis and phenotype identification. Precision medicine aims to tailor treatments to each individual patient based on their unique characteristics and disease mechanisms.

Endothelial Cell Dysfunction Due to Molecules Secreted by Macrophages in Sepsis

Sepsis is recognized as a syndrome of systemic inflammatory reaction induced by dysregulation of the body's immunity against infection. The multiple organ dysfunction associated with sepsis is a serious threat to the patient's life. Endothelial cell dysfunction has been extensively studied in sepsis. However, the role of macrophages in sepsis is not well understood and the intrinsic link between the two cells has not been elucidated. Macrophages are first-line cells of the immune response, whereas endothelial cells are a class of cells that are highly altered in function and morphology. In sepsis, various cytokines secreted by macrophages and endothelial cell dysfunction are inextricably linked. Therefore, investigating how macrophages affect endothelial cells could offer a theoretical foundation for the treatment of sepsis. This review links molecules (TNF-α, CCL2, ROS, VEGF, MMP-9, and NO) secreted by macrophages under inflammatory conditions to endothelial cell dysfunction (adhesion, permeability, and coagulability), refining the pathophysiologic mechanisms of sepsis. At the same time, multiple approaches (a variety of miRNA and medicines) regulating macrophage polarization are also summarized, providing new insights into reversing endothelial cell dysfunction and improving the outcome of sepsis treatment.

Suppression of Skp2 contributes to sepsis-induced acute lung injury by enhancing ferroptosis through the ubiquitination of SLC3A2

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. The inflammatory cytokine storm causes systemic organ damage, especially acute lung injury in sepsis. In this study, we found that the expression of S-phase kinase-associated protein 2 (Skp2) was significantly decreased in sepsis-induced acute lung injury (ALI). Sepsis activated the MEK/ERK pathway and inhibited Skp2 expression in the pulmonary epithelium, resulting in a reduction of K48 ubiquitination of solute carrier family 3 member 2 (SLC3A2), thereby impairing its membrane localization and cystine/glutamate exchange function. Consequently, the dysregulated intracellular redox reactions induced ferroptosis in pulmonary epithelial cells, leading to lung injury. Finally, we demonstrated that intravenous administration of Skp2 mRNA-encapsulating lipid nanoparticles (LNPs) inhibited ferroptosis in the pulmonary epithelium and alleviated lung injury in septic mice. Taken together, these data provide an innovative understanding of the underlying mechanisms of sepsis-induced ALI and a promising therapeutic strategy for sepsis.

Enhancing acute inflammatory and sepsis treatment: superiority of membrane receptor blockade

Conditions such as acute pancreatitis, ulcerative colitis, delayed graft function and infections caused by a variety of microorganisms, including gram-positive and gram-negative organisms, increase the risk of sepsis and therefore mortality. Immune dysfunction is a characterization of sepsis, so timely and effective treatment strategies are needed. The conventional approaches, such as antibiotic-based treatments, face challenges such as antibiotic resistance, and cytokine-based treatments have shown limited efficacy. To address these limitations, a novel approach focusing on membrane receptors, the initiators of the inflammatory cascade, is proposed. Membrane receptors such as Toll-like receptors, interleukin-1 receptor, endothelial protein C receptor, μ-opioid receptor, triggering receptor expressed on myeloid cells 1, and G-protein coupled receptors play pivotal roles in the inflammatory response, offering opportunities for rapid regulation. Various membrane receptor blockade strategies have demonstrated efficacy in both preclinical and clinical studies. These membrane receptor blockades act as early stage inflammation modulators, providing faster responses compared to conventional therapies. Importantly, these blockers exhibit immunomodulatory capabilities without inducing complete immunosuppression. Finally, this review underscores the critical need for early intervention in acute inflammatory and infectious diseases, particularly those posing a risk of progressing to sepsis. And, exploring membrane receptor blockade as an adjunctive treatment for acute inflammatory and infectious diseases presents a promising avenue. These novel approaches, when combined with antibiotics, have the potential to enhance patient outcomes, particularly in conditions prone to sepsis, while minimizing risks associated with antibiotic resistance and immune suppression.

Sepsis in elderly patients: the role of neutrophils in pathophysiology and therapy

Sepsis is among the most important causes of mortality, particularly within the elderly population. Sepsis prevalence is on the rise due to different factors, including increasing average population age and the concomitant rise in the prevalence of frailty and chronic morbidities. Recent investigations have unveiled a "trimodal" trajectory for sepsis-related mortality, with the ultimate zenith occurring from 60 to 90 days until several years after the original insult. This prolonged temporal course ostensibly emanates from the sustained perturbation of immune responses, persevering beyond the phase of clinical convalescence. This phenomenon is particularly associated with the aging immune system, characterized by a broad dysregulation commonly known as "inflammaging." Inflammaging associates with a chronic low-grade activation of the innate immune system preventing an appropriate response to infective agents. Notably, during the initial phases of sepsis, neutrophils-essential in combating pathogens-may exhibit compromised activity. Paradoxically, an overly zealous neutrophilic reaction has been observed to underlie multi-organ dysfunction during the later stages of sepsis. Given this scenario, discovering treatments that can enhance neutrophil activity during the early phases of sepsis while curbing their overactivity in the later phases could prove beneficial in fighting pathogens and reducing the detrimental effects caused by an overactive immune system. This narrative review delves into the potential key role of neutrophils in the pathological process of sepsis, focusing on how the aging process impacts their functions, and highlighting possible targets for developing immune-modulatory therapies. Additionally, the review includes tables that outline the principal potential targets for immunomodulating agents.

Design, synthesis, and anti-inflammatory activity of indole-2-formamide benzimidazole[2,1-b]thiazole derivatives

Molecular hybridization is a widely employed technique in medicinal chemistry for drug modification, aiming to enhance pharmacological activity and minimize side effects. The combination of an indole ring and imidazole[2,1-b]thiazole has shown promising potential as a group that exhibits potent anti-inflammatory effects. In this study, we designed and synthesized a series of derivatives comprising indole-2-formamide benzimidazole[2,1-b]thiazole to evaluate their impact on LPS-induced production of pro-inflammatory cytokines NO, IL-6, and TNF-α release, as well as iron death in RAW264.7 cells. The findings revealed that most compounds effectively inhibited LPS-induced production of pro-inflammatory cytokines NO, IL-6, and TNF-α release in RAW264.7 cells. Compound 13b exhibited the most potent anti-inflammatory activity among the tested compounds. The results of the cytotoxicity assay indicated that compound 13b was nontoxic. Additionally, compound 13b was found to elevate the levels of ROS, MDA, and Fe2+, while reducing GSH content, thereby facilitating the iron death process. Consequently, compound 13b showed promise for future development as an anti-inflammatory drug.

Design, Synthesis, and Biological Evaluation of a Novel NIK Inhibitor with Anti-Inflammatory and Hepatoprotective Effects for Sepsis Treatment

NIK plays a crucial role in the noncanonical NF-κB signaling pathway associated with diverse inflammatory and autoimmune diseases. Our study presents compound 54, a novel NIK inhibitor, designed through a structure-based scaffold-hopping approach from the previously identified B022. Compound 54 demonstrates remarkable selectivity and potency against NIK both in vitro and in vivo, effectively suppressing pro-inflammatory cytokines and nitric oxide production. In mouse models, compound 54 protected against LPS-induced systemic sepsis, reducing AST, ALT, and AKP liver injury markers. Additionally, it also attenuates sepsis-induced lung and kidney damage. Mechanistically, compound 54 blocks the noncanonical NF-κB signaling pathway by targeting NIK, preventing p100 to p52 processing. This work reveals a novel class of NIK inhibitors with significant potential for sepsis therapy.

The 12-Membered TNFR1 Peptide, as Well as the 16-Membered and 6-Membered TNF Peptides, Regulate TNFR1-Dependent Cytotoxic Activity of TNF

Understanding the exact mechanisms of the activation of proinflammatory immune response receptors is very important for the targeted regulation of their functioning. In this work, we were able to identify the sites of the molecules in the proinflammatory cytokine TNF (tumor necrosis factor) and its TNFR1 (tumor necrosis factor receptor 1), which are necessary for the two-stage cytotoxic signal transduction required for tumor cell killing. A 12-membered TNFR1 peptide was identified and synthesized, interacting with the ligands of this receptor protein's TNF and Tag7 and blocking their binding to the receptor. Two TNF cytokine peptides interacting with different sites of TNFR1 receptors were identified and synthesized. It has been demonstrated that the long 16-membered TNF peptide interferes with the binding of TNFR1 ligands to this receptor, and the short 6-membered peptide interacts with the receptor site necessary for the transmission of a cytotoxic signal into the cell after the ligands' interaction with the binding site. This study may help in the development of therapeutic approaches to regulate the activity of the cytokine TNF.

Claudin-2 upregulation enhances intestinal permeability, immune activation, dysbiosis, and mortality in sepsis

Intestinal epithelial expression of the tight junction protein claudin-2, which forms paracellular cation and water channels, is precisely regulated during development and in disease. Here, we show that small intestinal epithelial claudin-2 expression is selectively upregulated in septic patients. Similar changes occurred in septic mice, where claudin-2 upregulation coincided with increased flux across the paracellular pore pathway. In order to define the significance of these changes, sepsis was induced in claudin-2 knockout (KO) and wild-type (WT) mice. Sepsis-induced increases in pore pathway permeability were prevented by claudin-2 KO. Moreover, claudin-2 deletion reduced interleukin-17 production and T cell activation and limited intestinal damage. These effects were associated with reduced numbers of neutrophils, macrophages, dendritic cells, and bacteria within the peritoneal fluid of septic claudin-2 KO mice. Most strikingly, claudin-2 deletion dramatically enhanced survival in sepsis. Finally, the microbial changes induced by sepsis were less pathogenic in claudin-2 KO mice as survival of healthy WT mice injected with cecal slurry collected from WT mice 24 h after sepsis was far worse than that of healthy WT mice injected with cecal slurry collected from claudin-2 KO mice 24 h after sepsis. Claudin-2 upregulation and increased pore pathway permeability are, therefore, key intermediates that contribute to development of dysbiosis, intestinal damage, inflammation, ineffective pathogen control, and increased mortality in sepsis. The striking impact of claudin-2 deletion on progression of the lethal cascade activated during sepsis suggests that claudin-2 may be an attractive therapeutic target in septic patients.

The causal effects of circulating cytokines on sepsis: a Mendelian randomization study

Background

In observational studies, sepsis and circulating levels of cytokines have been associated with unclear causality. This study used Mendelian randomization (MR) to identify the causal direction between circulating cytokines and sepsis in a two-sample study.

Methods

An MR analysis was performed to estimate the causal effect of 41 cytokines on sepsis risk. The inverse-variance weighted random-effects method, the weighted median-based method, and MR-Egger were used to analyze the data. Heterogeneity and pleiotropy were assessed using MR-Egger regression and Cochran's Q statistic.

Results

Genetically predicted beta-nerve growth factor (OR = 1.12, 95% CI [1.037-1.211], P = 0.004) increased the risk of sepsis, while RANTES (OR = 0.92, 95% CI [0.849-0.997], P = 0.041) and fibroblast growth factor (OR = 0.869, 95% CI [0.766-0.986], P = 0.029) reduced the risk of sepsis. These findings were robust in extensive sensitivity analyses. There was no clear association between the other cytokines and sepsis risk.

Conclusion

The findings of this study demonstrate that beta-nerve growth factor, RANTES, and fibroblast growth factor contribute to sepsis risk. Investigations into potential mechanisms are warranted.

CIAP1/2 can regulate the inflammatory response and lung injury induced by apoptosis in septic rats

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), induced by sepsis, is predominantly caused by inflammation injury. However, there is no clear consensus on how to regulate the inflammatory response. The TNF pathway is one of the primary inflammatory pathways activated in sepsis. cIAP1/2, an essential E3 ubiquitin ligase in the TNF pathway, plays a pivotal role in positively regulating the activation of nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways to promote inflammation while inhibiting apoptosis. We found that Birc2 is the only differential expression gene in TNF pathway, and both cIAP1/2 upregulated in lung lysate with worsen lung injury. However, upon inhibiting cIAP1/2 using AZD5582, lung cell apoptosis was reactivated, and a significant improvement in lung injury was observed. Our study shows that cIAP1/2 expression increased in the lung tissue of a CLP rat ALI model. Inhibiting cIAP1/2 with AZD5582, a second mitochondria-derived activator of caspases (SMAC) mimetic, induced increased apoptosis and reduced lung injury. Therefore, inhibiting cIAP1/2 can alleviate sepsis-induced ALI, providing a new target for regulating organ damage induced by sepsis-induced inflammatory responses.

Antimicrobial stewardship and targeted therapies in the changing landscape of maternal sepsis

Pregnant and postnatal women are a high-risk population particularly prone to rapid progression to sepsis with significant morbidity and mortality worldwide. Moreover, severe maternal infections can have a serious detrimental impact on neonates with almost 1 million neonatal deaths annually attributed to maternal infection or sepsis. In this review we discuss the susceptibility of pregnant women and their specific physiological and immunological adaptations that contribute to their vulnerability to sepsis, the implications for the neonate, as well as the issues with antimicrobial stewardship and the challenges this poses when attempting to reach a balance between clinical care and urgent treatment. Finally, we review advancements in the development of pregnancy-specific diagnostic and therapeutic approaches and how these can be used to optimize the care of pregnant women and neonates.

Targeting the host response in sepsis: current approaches and future evidence

Sepsis, a dysregulated host response to infection characterized by organ failure, is one of the leading causes of death worldwide. Disbalances of the immune response play an important role in its pathophysiology. Patients may develop simultaneously or concomitantly states of systemic or local hyperinflammation and immunosuppression. Although a variety of effective immunomodulatory treatments are generally available, attempts to inhibit or stimulate the immune system in sepsis have failed so far to improve patients' outcome. The underlying reason is likely multifaceted including failure to identify responders to a specific immune intervention and the complex pathophysiology of organ dysfunction that is not exclusively caused by immunopathology but also includes dysfunction of the coagulation system, parenchymal organs, and the endothelium. Increasing evidence suggests that stratification of the heterogeneous population of septic patients with consideration of their host response might led to treatments that are more effective. The purpose of this review is to provide an overview of current studies aimed at optimizing the many facets of host response and to discuss future perspectives for precision medicine approaches in sepsis.

The effects of etomidate on expression of high mobility group box 1 via the nuclear factor kappa B pathway in rat model of sepsis

Etomidate is an anesthetic agent used in hemodynamically unstable patients, but its use has been controversial in septic patients. The response of high-mobility group box 1 (HMGB1), a late-phase lethal cytokine in sepsis, to etomidate has not been reported. This study investigated the effects of etomidate on the expression and release of HMGB1 and the underlying mechanism using a cecal ligation and puncture (CLP) model. Thirty-six male Sprague-Dawley rats were divided into sham, CLP, and Etomi groups. Sepsis was induced in the CLP and Etomi groups, and intravenous etomidate (4 mg/kg) was infused for 40 min immediately after operation in the Etomi group. Serum creatinine, alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and HMGB1 levels were measured 6 and 24 hours after surgery. Activation of nuclear factor (NF)-ĸB and HMGB1 mRNA expression in the liver, lung, kidney, and ileum tissues were measured, and immunohistochemical staining of HMGB1 was implemented. Increases of the TNF-α level 6 h after CLP and ALT and IL-6 levels 24 h after CLP were significantly inhibited by etomidate treatment. Etomidate treatment also significantly attenuated the increase in serum HMGB1 level at 6 and 24 h after CLP and suppressed the NF-ĸB and HMGB1 mRNA in multiple organs 24 h after CLP. Immunohistochemical staining also revealed that etomidate treatment inhibited HMGB1 expression. Etomidate inhibited the systemic release of HMGB1 and its expression in various organs. The mechanism may be associated with the inhibitory effects of etomidate on pro-inflammatory cytokine release and NF-ĸB activity.

Host and Pathogen-Directed Therapies against Microbial Infections Using Exosome- and Antimicrobial Peptide-derived Stem Cells with a Special look at Pulmonary Infections and Sepsis

Microbial diseases are a great threat to global health and cause considerable mortality and extensive economic losses each year. The medications for treating this group of diseases (antibiotics, antiviral, antifungal drugs, etc.) directly attack the pathogenic agents by recognizing the target molecules. However, it is necessary to note that excessive use of any of these drugs can lead to an increase in microbial resistance and infectious diseases. New therapeutic methods have been studied recently using emerging drugs such as mesenchymal stem cell-derived exosomes (MSC-Exos) and antimicrobial peptides (AMPs), which act based on two completely different strategies against pathogens including Host-Directed Therapy (HDT) and Pathogen-Directed Therapy (PDT), respectively. In the PDT approach, AMPs interact directly with pathogens to interrupt their intrusion, survival, and proliferation. These drugs interact directly with the cell membrane or intracellular components of pathogens and cause the death of pathogens or inhibit their replication. The mechanism of action of MSC-Exos in HDT is based on immunomodulation and regulation, promotion of tissue regeneration, and reduced host toxicity. This review studies the potential of mesenchymal stem cell-derived exosomes/ATPs therapeutic properties against microbial infectious diseases especially pulmonary infections and sepsis.

Sodium tanshinone IIA sulfonate attenuates sepsis-associated brain injury via inhibiting NOD-like receptor 3/caspase-1/gasdermin D-mediated pyroptosis

BACKGROUND

Sodium tanshinone IIA sulfonate (STS) has been reported to protect organ function in sepsis. However, the attenuation of sepsis-associated brain injury and its underlying mechanisms by STS has not been established.

METHODS

C57BL/6 mice were used to establish the cecal ligation perforation (CLP) model, and STS was injected intraperitoneally 30 min before the surgery. The BV2 cells were stimulated by lipopolysaccharide after being pre-treated with STS for 4 h. The STS protective effects against brain injury and in vivo anti-neuroinflammatory effects were investigated using the 48-hour survival rate and body weight changes, brain water content, histopathological staining, immunohistochemistry, ELISA, RT-qPCR, and transmission electron microscopy. The pro-inflammatory cytokines of BV2 cells were detected by ELISA and RT-qPCR. At last, the levels of NOD-like receptor 3 (NLRP3) inflammasome activation and pyroptosis in brain tissues of the CLP model and BV2 cells were detected using western blotting.

RESULTS

STS increased the survival rate, decreased brain water content, and improved brain pathological damage in the CLP models. STS increased the expressions of tight junction proteins ZO-1 and Claudin5 while reducing the expressions of tumor necrosis factor α (TNF-α), interleukin-1β(IL-1β), and interleukin-18 (IL-18) in the brain tissues of the CLP models. Meanwhile, STS inhibited microglial activation and M1-type polarization in vitro and in vivo. The NLRP3/caspase-1/ gasdermin D (GSDMD)-mediated pyroptosis was activated in the brain tissues of the CLP models and lipopolysaccharide (LPS)-treated BV2 cells, which was significantly inhibited by STS.

CONCLUSIONS

The activation of NLRP3/caspase-1/GSDMD-mediated pyroptosis and subsequent secretion of proinflammatory cytokines may be the underlying mechanisms of STS against sepsis-associated brain injury and neuroinflammatory response.

Immunotherapies against human bacterial and fungal infectious diseases: A review

Nations' ongoing struggles with a number of novel and reemerging infectious diseases, including the ongoing global health issue, the SARS-Co-V2 (severe acute respiratory syndrome coronavirus 2) outbreak, serve as proof that infectious diseases constitute a serious threat to the global public health. Moreover, the fatality rate in humans is rising as a result of the development of severe infectious diseases brought about by multiple drug-tolerant pathogenic microorganisms. The widespread use of traditional antimicrobial drugs, immunosuppressive medications, and other related factors led to the establishment of such drug resistant pathogenic microbial species. To overcome the difficulties commonly encountered by current infectious disease management and control processes, like inadequate effectiveness, toxicities, and the evolution of drug tolerance, new treatment solutions are required. Fortunately, immunotherapies already hold great potential for reducing these restrictions while simultaneously expanding the boundaries of healthcare and medicine, as shown by the latest discoveries and the success of drugs including monoclonal antibodies (MAbs), vaccinations, etc. Immunotherapies comprise methods for treating diseases that specifically target or affect the body's immune system and such immunological procedures/therapies strengthen the host's defenses to fight those infections. The immunotherapy-based treatments control the host's innate and adaptive immune responses, which are effective in treating different pathogenic microbial infections. As a result, diverse immunotherapeutic strategies are being researched more and more as alternative treatments for infectious diseases, leading to substantial improvements in our comprehension of the associations between pathogens and host immune system. In this review we will explore different immunotherapies and their usage for the assistance of a broad spectrum of infectious ailments caused by various human bacterial and fungal pathogenic microbes. We will discuss about the recent developments in the therapeutics against the growing human pathogenic microbial diseases and focus on the present and future of using immunotherapies to overcome these diseases. Graphical AbstractThe graphical abstract shows the therapeutic potential of different types of immunotherapies like vaccines, monoclonal antibodies-based therapies, etc., against different kinds of human Bacterial and Fungal microbial infections.

NSC228155 alleviates septic cardiomyopathy via protecting mitochondria and inhibiting inflammation

Septic cardiomyopathy is a lethal symptom of sepsis. Discovery of effective therapy that prevents cardiac injury in sepsis is critical in the clinical management of sepsis. NSC228155 is a novel compound with therapeutic potential on acute kidney injury by preventing apoptosis and protecting mitochondria. Whether NSC228155 protects against septic cardiomyopathy is unclear. In the present study, adult C57BL/6J mice were i.p injected with 5 mg/kg/day NSC228155 for 2 days before 10 mg/kg lipopolysaccharide (LPS) injection. Cardiac functional testing and sampling for serum and tissue were performed 12 and 24 h post LPS injection, respectively. NSC228155 significantly improved cardiac function examined by echocardiography, decreased the serum lactate dehydrogenase (LDH) and creatine kinase-MB, and pathologically alleviated cardiac injury in LPS mice. Accordingly, NSC228155 attenuated cardiomyocytes' mitochondrial damage as shown by decreased damaged mitochondrial ratio and activated signals for mitochondrial biogenesis, dynamics and mitophagy in LPS mice model. Metabolomics analysis demonstrated that NSC228155 corrected the metabolic disturbance involved in oxidative stress and energy metabolism, and decreased tissue injury metabolites in LPS-stimulated cardiac tissue. In the LPS-stimulated cardiac cell culture derived from human induced pluripotent stem cells, NSC228155 effectively restored the beating frequency, decreased LDH release, and protected mitochondria. NSC228155 also inhibited inflammation shown by decreased pro-inflammatory mediators in both serum and cardiac tissue in LPS model. Taken together, NSC228155 significantly improved cardiac function by directly preventing against cardiac cell injury and inhibiting inflammation in LPS model, hence may be a potential novel therapy against septic cardiomyopathy.

The natural history of COVID-19 in vaccinated inflammatory bowel disease patients

AIM

Assess the characteristics of break through COVID-19 in Inflammatory Bowel Disease (IBD) patients, despite complete vaccination.

METHODS

Patients who reported a COVID-19 at least 3 weeks after complete vaccination were asked to answer an on-line anonymous questionnaire which included patient and disease characteristics, vaccination history, and the evolution of COVID-19.

RESULTS

Among 3240 IBD patients who reported complete vaccination between 1st May 2021 and 30thJune 2022, 402 (12.4%) were infected by SARS Cov-2 [223 male, 216 Crohn's disease (CD), 186 Ulcerative Colitis (UC), mean (SD) age 42.3 (14.9) years, mean (SD) IBD duration 10.1 (9.7) years]. Three hundred and sixty-nine patients (91.8%) were infected once and 33 (8.2%) twice. The mean (SD) time between last vaccination and infection was 4.1 (1.6) months. Overall, 351 (87.3%) patients reported mild constitutional and/or respiratory symptoms, 34 (8.4%) were asymptomatic and only 17 patients (4.2%) required hospitalization. Of hospitalized patients, 2 UC patients died of COVID-19 pneumonia. The remaining hospitalized patients did not need high flow oxygen supply or ICU admission.

CONCLUSIONS

A minority of completely vaccinated IBD patients developed COVID-19 which evolved with mild symptoms and a favorable outcome. These results reinforce the importance of vaccination especially in vulnerable populations.

Transcutaneous auricular vagus nerve stimulation reduces cytokine production in sepsis: An open double-blind, sham-controlled, pilot study

BACKGROUND

Studies have shown that vagus nerve-mediated inflammatory reflex could inhibit cytokine production and inflammation in sepsis animals.

OBJECTIVES

This study aimed to explore the efficacy of transcutaneous auricular vagus nerve stimulation (taVNS) on inflammation and disease severity of sepsis patients.

METHODS

A randomized, double-blind, sham-controlled pilot study was performed. Twenty sepsis patients were randomly assigned to receive taVNS or sham stimulation for five consecutive days. Stimulation effect was assessed with serum cytokine levels, Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score, and Sequential Organ Failure Assessment (SOFA) score at baseline and on Day 3, Day 5, and Day 7.

RESULTS

TaVNS was well tolerated in the study population. Patients receiving taVNS experienced significant reductions in serum TNF-α and IL-1β levels and increases in IL-4 and IL-10 levels. SOFA scores decreased on Day 5 and Day 7 compared with baseline in the taVNS group. However, no changes were found in sham stimulation group. The changes of cytokine from Day 7 to Day 1 were greater with taVNS than sham stimulation. No differences in the APACHE Ⅱ score and SOFA score were observed between the two groups.

CONCLUSIONS

TaVNS resulted in significantly lower serum pro-inflammatory cytokines and higher serum anti-inflammatory cytokines in sepsis patients.

Heart Failure in Rheumatic Disease: Secular Trends and Novel Insights

There is a significant increase in risk of heart failure in several rheumatic diseases. Common cardiovascular risk factors and inflammatory processes, present in both rheumatic diseases and heart failure, are contributing to this increase. The opportunities for using immune-based strategies to fight development of heart failure in rheumatic diseases are evolving. The diversity of inflammation calls for a tailored characterization of inflammation, enabling differentiation of inflammation and subsequent introduction of precision medicine using target-specific strategies and immunomodulatory therapy. As the field of rheuma-cardiology is still evolving, clear recommendations cannot be given yet.

Molecular mechanisms of cell death in bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) in neonates is the most common pulmonary disease that causes neonatal mortality, has complex pathogenesis, and lacks effective treatment. It is associated with chronic obstructive pulmonary disease, pulmonary hypertension, and right ventricular hypertrophy. The occurrence and development of BPD involve various factors, of which premature birth is the most crucial reason for BPD. Under the premise of abnormal lung structure and functional product, newborns are susceptible to damage to oxides, free radicals, hypoxia, infections and so on. The most influential is oxidative stress, which induces cell death in different ways when the oxidative stress balance in the body is disrupted. Increasing evidence has shown that programmed cell death (PCD), including apoptosis, necrosis, autophagy, and ferroptosis, plays a significant role in the molecular and biological mechanisms of BPD and the further development of the disease. Understanding the mode of PCD and its signaling pathways can provide new therapeutic approaches and targets for the clinical treatment of BPD. This review elucidates the mechanism of BPD, focusing on the multiple types of PCD in BPD and their molecular mechanisms, which are mainly based on experimental results obtained in rodents.

Exploring the perspective of patients with immune-mediated inflammatory diseases and care providers on the use of immunomodulatory drugs in infections: an interview study

Objectives

Immunomodulatory agents are safe and effective as treatment for various immune-mediated inflammatory diseases (IMIDs), but are associated with a slightly increased infection risk. It is uncertain whether, in the event of an infection, continuation or temporary interruption of immunomodulatory agents leads to better outcomes. Owing to this uncertainty, it is of importance to explore the perspectives of health-care providers (HCPs) and patients on this topic. In this study, we set out to identify and provide an overview of reasons for both treatment strategies.

Methods

Semi-structured interviews were conducted with HCPs involved in the pharmacological treatment of IMIDs and with IMID patients using one or more immunomodulatory agent. Purposive sampling was used to enrich data variation. Interviews were conducted until data saturation was reached and subsequently analysed using qualitative content analysis.

Results

In total, 13 HCPs and 19 IMID patients were interviewed. A wide range of reasons for both treatment strategies were identified, categorized into 10 overarching themes, including IMID characteristics, infection characteristics and the patient-HCP relationship.

Conclusion

In this interview study, we identified various reasons for continuation or temporary interruption of immunomodulatory agents during infections for both IMID patients and HCPs. We found overlapping themes, such as IMID characteristics; however, the content and interpretation of these themes might differ between HCPs and patients. Both HCPs and patients mentioned that the decision for a treatment strategy is often about weighing benefits against risks (e.g. infection severity vs disease flare).

Biological age and environmental risk factors for dementia and stroke: Molecular mechanisms

Since the development of antibiotics and vaccination, as well as major improvements in public hygiene, the main risk factors for morbidity and mortality are age and chronic exposure to environmental factors, both of which can interact with genetic predispositions. As the average age of the population increases, the prevalence and costs of chronic diseases, especially neurological conditions, are rapidly increasing. The deleterious effects of age and environmental risk factors, develop chronically over relatively long periods of time, in contrast to the relatively rapid deleterious effects of infectious diseases or accidents. Of particular interest is the hypothesis that the deleterious effects of environmental factors may be mediated by acceleration of biological age. This hypothesis is supported by evidence that dietary restriction, which universally delays age-related diseases, also ameliorates deleterious effects of environmental factors. Conversely, both age and environmental risk factors are associated with the accumulation of somatic mutations in mitotic cells and epigenetic modifications that are a measure of "biological age", a better predictor of age-related morbidity and mortality than chronological age. Here we review evidence that environmental risk factors such as smoking and air pollution may also drive neurological conditions, including Alzheimer's Disease, by the acceleration of biological age, mediated by cumulative and persistent epigenetic effects as well as somatic mutations. Elucidation of such mechanisms could plausibly allow the development of interventions which delay deleterious effects of both aging and environmental risk factors.

Novel 2-phenyl-4H-chromen derivatives: synthesis and anti-inflammatory activity evaluation in vitro and in vivo

It is significant to design, synthesise and optimise flavonoid derivatives with better anti-inflammatory activity. This study aims to design and synthesise a series of novel 2-phenyl-4H-chromen-4-one compounds with anti-inflammatory; among them, compound 8 was discovered as the best one. And then, the effects of compound 8 on the TLR4/MAPK signalling pathway was carried out in vivo, the results indicated that compound 8 could downregulate NO, IL-6, and TNF-α expression, and suppress LPS-induced inflammation by inhibiting the TLR4/MAPK pathways. Furthermore, compound 8 reduced inflammation by a mouse model of LPS-induced inflammatory disease in vivo. The results suggest that compound 8 has the potential against inflammation through regulating TLR4/MAPK pathway and can be assessed further for drug development.

Infliximab in the treatment of patients with severe COVID-19 (INFLIXCOVID): protocol for a randomised, controlled, multicentre, open-label phase II clinical study

Background

Despite the intense global research endeavour to improve the treatment of patients with COVID-19, the current therapy remains insufficient, resulting in persisting high mortality. Severe cases are characterised by a systemic inflammatory reaction driven by the release of pro-inflammatory cytokines such as IL-6 and tumour-necrosis-factor alpha (TNF-α). TNF-α-blocking therapies have proved beneficial in patients with chronic inflammatory diseases and could therefore pose a new treatment option in COVID-19. Hitherto, no results from randomised controlled trials assessing the effectiveness and safety of infliximab—a monoclonal antibody targeting TNF-α—in the treatment of COVID-19 have been published.

Methods

In this phase-2 clinical trial, patients with COVID-19 and clinical and laboratory signs of hyperinflammation will be randomised to receive either one dose of infliximab (5 mg/kg body weight) in addition to the standard of care or the standard of care alone. The primary endpoint is the difference in 28-day mortality. Further assessments concern the safety of infliximab therapy in COVID-19 and the influence of infliximab on morbidity and the course of the disease. For the supplementary scientific programme, blood and urine samples are collected to assess concomitant molecular changes. The Ethics Committee of the Friedrich Schiller University Jena (2021-2236-AMG-ff) and the Paul-Ehrlich-Institute (4513/01) approved the study.

Discussion

The results of this study could influence the therapy of patients with COVID-19 and affect the course of the disease worldwide, as infliximab is globally available and approved by several international drug agencies.

Trial registration

The trial was registered at clinicaltrials.gov (NCT04922827, 11 June 2021) and at EudraCT (2021-002098-25, 19 May 2021).

The Severity of Acute Kidney and Lung Injuries Induced by Cecal Ligation and Puncture Is Attenuated by Menthol: Role of Proliferating Cell Nuclear Antigen and Apoptotic Markers

Objective

Sepsis-induced acute lung injury (ALI) and acute kidney injury (AKI) are major causes of mortality. Menthol is a natural compound that has anti-inflammatory and antioxidative actions. Since exaggerated inflammatory and oxidative stress are characteristics of sepsis, the aim of this study was to evaluate the effect of menthol against sepsis-induced mortality, ALI, and AKI.

Methods

The cecal ligation and puncture (CLP) procedure was employed as a model of sepsis. Rats were grouped into sham, sham-Menthol, CLP, and CLP-Menthol (100 mg/kg, p.o).

Key Findings

A survival study showed that menthol enhanced the survival after sepsis from 0% in septic group to 30%. Septic rats developed histological evidence of ALI and AKI. Menthol markedly suppressed sepsis induced elevation of tissue TNF-a, ameliorated sepsis-induced cleavage of caspase-3 and restored the antiapoptotic marker Bcl2.

Significance

We introduced a role of the proliferating cell nuclear antigen (PCNA) in these tissues with a possible link to the damage induced by sepsis. PCNA level was markedly reduced in septic animals and menthol ameliorated this effect. Our data provide novel evidence that menthol protects against organ damage and decreases mortality in experimental sepsis.

Heart Failure Relapses in Response to Acute Stresses - Role of Immunological and Inflammatory Pathways

Cardiovascular diseases continue to be the most imminent health care problems in the western world, accounting for numerous deaths per year. Heart failure (HF), namely the reduction of left ventricular function, is one of the major cardiovascular disease entities. It is chronically progressing with relapsing acute decompensations and an overall grave prognosis that is little different if not worse than most malignant diseases. Interestingly acute metabolically and/or immunologically challenging events like infections or major surgical procedures will cause relapses in the course of preexisting chronic heart failure, decrease the patients wellbeing and worsen myocardial function. HF itself and or its progression has been demonstrated to be driven at least in part by inflammatory pathways that are similarly turned on by infectious or non-infectious stress responses. These thus add to HF progression or relapse. TNF-α plasma levels are associated with disease severity and progression in HF. In addition, several cytokines (e.g., IL-1β, IL-6) are involved in deteriorating left ventricular function. Those observations are based on clinical studies using inhibitors of cytokines or their receptors or they stem from animal studies examining the effect of cytokine mediated inflammation on myocardial remodeling in models of heart failure. This short review summarizes the known underlying immunological processes that are shared by and drive all: chronic heart failure, select infectious diseases, and inflammatory stress responses. In conclusion the text provides a brief summary of the current development in immunomodulatory therapies for HF and their overlap with treatments of other disease entities.

Molecular Docking Analysis from Bryophyllum pinnatum Compound as A COVID-19 Cytokine Storm Therapy

BACKGROUND: Cytokine storm is a condition that typically develops during severe COVID-19 viral infection and contributes cause of death. Bryophyllum pinnatum is a herbal medicinal that has an impact as an anti-inflammatory agent. B. pinnatum may be used as a therapeutic agent for cytokine storms. AIM: We were investigating the molecular interactions of B. pinnatum active compounds with cytokines involved in COVID-19 infection. METHODS: We did the molecular docking approach using the active chemicals from Bryphyllum pinnatum, which was available on the PubChem website. Meanwhile, the protein utilized is retrieved from the protein databank. Pyrx 9.5, Pymol, and Discovery Studio software were used to evaluate and visualize the interaction results between ligands and the proteins formed. RESULTS: Bryophyllin B has the strongest affinity to IL-6, whereas Bryotoxin A had the highest binding to Gly-ACE and TNF alpha. Pharmacokinetic predictions indicate that Bryophyllin B has a good pharmacokinetic profile but a low toxicity profile due to a reproductive effect. On the other hand, Bryotoxin A has a poor pharmacokinetic profile but is safe for human use. CONCLUSIONS: Bryophyllin B and Bryotoxin A show potential as a therapy for the cytokine storm of COVID-19 infection. However, further study is required to examine the effectiveness and toxicity of these compounds.

Recombinant Human Lactoferrin Reduces Inflammation and Increases Fluoroquinolone Penetration to Primary Granulomas During Mycobacterial Infection of C57Bl/6 Mice

Infection with Mycobacterium tuberculosis (Mtb) results in the primary formation of a densely packed inflammatory foci that limits entry of therapeutic agents into pulmonary sites where organisms reside. No current therapeutic regimens exist that modulate host immune responses to permit increased drug penetration to regions of pathological damage during tuberculosis disease. Lactoferrin is a natural iron-binding protein previously demonstrated to modulate inflammation and granuloma cohesiveness, while maintaining control of pathogenic burden. Studies were designed to examine recombinant human lactoferrin (rHLF) to modulate histological progression of Mtb-induced pathology in a non-necrotic model using C57Bl/6 mice. The rHLF was oral administered at times corresponding to initiation of primary granulomatous response, or during granuloma maintenance. Treatment with rHLF demonstrated significant reduction in size of primary inflammatory foci following Mtb challenge, and permitted penetration of ofloxacin fluoroquinolone therapeutic to sites of pathological disruption where activated (foamy) macrophages reside. Increased drug penetration was accompanied by retention of endothelial cell integrity. Immunohistochemistry revealed altered patterns of M1-like and M2-like phenotypic cell localization post infectious challenge, with increased presence of M2-like markers found evenly distributed throughout regions of pulmonary inflammatory foci in rHLF-treated mice.

Tumor Necrosis Factor-α Mediates Lung Injury in the Early Phase of Endotoxemia

Endotoxemia induces lung injury. We assessed the therapeutic efficacy between triple cytokine (tumor necrosis factor-α [TNF-α], interleukin-1β [IL-1β], and IL-6) inhibition (mediated by KCF18 peptide) and single cytokine (TNF-α) inhibition (mediated by SEM18 peptide) on alleviating lung injury in the early phase of endotoxemia. Mice receiving endotoxin (Endo group), endotoxin plus KCF18 (EKCF group), or endotoxin plus SEM18 (ESEM) were monitored and euthanized at 24 h after endotoxin. Our data demonstrated altered lung function (decreases in tidal volume, minute ventilation, and dynamic compliance; and by contrast, increases in airway resistance and end expiration work) and histology (increases in injury scores, leukocyte infiltration, vascular permeability, and tissue water content) in the Endo group with significant protection observed in the EKCF and ESEM groups (all p < 0.05). Levels of inflammation (macrophage activation and cytokine upregulations), oxidation (lipid peroxidation), necroptosis, pyroptosis, and apoptosis in EKCF and ESEM groups were comparable and all were significantly lower than in the Endo group (all p < 0.05). These data demonstrate that single cytokine TNF-α inhibition can achieve therapeutic effects similar to triple cytokines TNF-α, IL-1β, and IL-6 inhibition on alleviating endotoxin-induced lung injury, indicating that TNF-α is the major cytokine in mediating lung injury in the early phase of endotoxemia.

Maoto, a traditional Japanese medicine, controls acute systemic inflammation induced by polyI:C administration through noradrenergic function

Maoto, a traditional Japanese medicine (Kampo), is widely used to treat upper respiratory tract infections, including influenza virus infection. Although maoto is known to inhibit pro-inflammatory responses in a rodent model of acute inflammation, its underlying mechanism remains to be determined. In this study, we investigated the involvement of immune responses and noradrenergic function in the inhibitory action of maoto. In a mouse model of polyI:C-induced acute inflammation, maoto was administered orally in conjunction with intraperitoneal injection of PolyI:C (6 mg/kg), and blood was collected after 2 h for measurement of plasma cytokines by ELISA. Maoto significantly decreased PolyI:C-induced TNF-α levels and increased IL-10 production. Neither pretreatment with IL-10 neutralizing antibodies nor T-cell deficiency using nude mice modified the inhibitory effect of maoto, indicating that the anti-inflammatory effects of maoto are independent of IL-10 and T cells. Furthermore, the inhibitory effects of maoto on PolyI:C-induced TNF-α production were not observed in ex vivo splenocytes, suggesting that maoto does not act directly on inflammatory cells. Lastly, pretreatment with a β-adrenergic receptor antagonist partially cancelled the anti-inflammatory effects of maoto. Collectively, these results suggest that maoto mediates its anti-inflammatory effects via β-adrenergic receptors in vivo.

Differential Co-Expression Network Analysis Reveals Key Hub-High Traffic Genes as Potential Therapeutic Targets for COVID-19 Pandemic

Background

The recent emergence of COVID-19, rapid worldwide spread, and incomplete knowledge of molecular mechanisms underlying SARS-CoV-2 infection have limited development of therapeutic strategies. Our objective was to systematically investigate molecular regulatory mechanisms of COVID-19, using a combination of high throughput RNA-sequencing-based transcriptomics and systems biology approaches.

Methods

RNA-Seq data from peripheral blood mononuclear cells (PBMCs) of healthy persons, mild and severe 17 COVID-19 patients were analyzed to generate a gene expression matrix. Weighted gene co-expression network analysis (WGCNA) was used to identify co-expression modules in healthy samples as a reference set. For differential co-expression network analysis, module preservation and module-trait relationships approaches were used to identify key modules. Then, protein-protein interaction (PPI) networks, based on co-expressed hub genes, were constructed to identify hub genes/TFs with the highest information transfer (hub-high traffic genes) within candidate modules.

Results

Based on differential co-expression network analysis, connectivity patterns and network density, 72% (15 of 21) of modules identified in healthy samples were altered by SARS-CoV-2 infection. Therefore, SARS-CoV-2 caused systemic perturbations in host biological gene networks. In functional enrichment analysis, among 15 non-preserved modules and two significant highly-correlated modules (identified by MTRs), 9 modules were directly related to the host immune response and COVID-19 immunopathogenesis. Intriguingly, systemic investigation of SARS-CoV-2 infection identified signaling pathways and key genes/proteins associated with COVID-19's main hallmarks, e.g., cytokine storm, respiratory distress syndrome (ARDS), acute lung injury (ALI), lymphopenia, coagulation disorders, thrombosis, and pregnancy complications, as well as comorbidities associated with COVID-19, e.g., asthma, diabetic complications, cardiovascular diseases (CVDs), liver disorders and acute kidney injury (AKI). Topological analysis with betweenness centrality (BC) identified 290 hub-high traffic genes, central in both co-expression and PPI networks. We also identified several transcriptional regulatory factors, including NFKB1, HIF1A, AHR, and TP53, with important immunoregulatory roles in SARS-CoV-2 infection. Moreover, several hub-high traffic genes, including IL6, IL1B, IL10, TNF, SOCS1, SOCS3, ICAM1, PTEN, RHOA, GDI2, SUMO1, CASP1, IRAK3, HSPA5, ADRB2, PRF1, GZMB, OASL, CCL5, HSP90AA1, HSPD1, IFNG, MAPK1, RAB5A, and TNFRSF1A had the highest rates of information transfer in 9 candidate modules and central roles in COVID-19 immunopathogenesis.

Conclusion

This study provides comprehensive information on molecular mechanisms of SARS-CoV-2-host interactions and identifies several hub-high traffic genes as promising therapeutic targets for the COVID-19 pandemic.

(R)-Ketamine ameliorates lethal inflammatory responses and multi-organ injury in mice induced by cecum ligation and puncture

AIMS

Sepsis is a life-threatening organ dysfunction syndrome arising from infection-induced uncontrolled systemic inflammatory responses. Patients surviving severe sepsis also exhibit increased mortality due to enhanced vulnerability to infections. In this study, we examined whether (R)-ketamine could prevent against lethal sepsis-induced systemic inflammation and inflammatory organ injury.

MAIN METHODS

Septic model was induced by cecal ligation and puncture (CLP) surgery on adult mice. (R)-ketamine (10 or 15 mg/kg) was administrated intraperitoneally (i.p.) 24 h before and/or immediately after CLP.

KEY FINDINGS

Combined prophylactic and therapeutic use of (R)-ketamine (10 mg/kg), as well as either prophylactic or therapeutic use of (R)-ketamine at a single dose of 15 mg/kg did not reduce 14-day mortality after CLP. However, combined prophylactic and therapeutic use of (R)-ketamine (15 mg/kg) significantly increased 14-day survival rate, attenuated sepsis-induced marked drop in the rectal temperature and increase in the plasma levels of inflammatory cytokines [i.e., interleukin (IL)-6, IL-17A, tumor necrosis factor (TNF)-α, IL-1β, and IL-10] 12 h after CLP. Furthermore, (R)-ketamine alleviated sepsis-induced increase in the organ injury markers such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), myocardial kinase (CK-MB), and creatinine 24 h after CLP. Moreover, the increased lung wet/dry weight ratio, pulmonary morphological injury and the pulmonary levels of inflammatory cytokines were also attenuated by (R)-ketamine.

SIGNIFICANCE

Combined prophylactic and therapeutic use of (R)-ketamine could attenuate systemic inflammation and inflammatory multi-organ injury in mice after CLP-induced lethal sepsis. Therefore, (R)-ketamine would be a potential prophylactic and therapeutic drug for patients prone to sepsis.

Clinical Significance of Pro-inflammatory Cytokines and Their Correlation with Disease Severity and Blood Coagulation in Septic Patients with Bacterial Co-infection

PURPOSE

To evaluate the clinical significance of pro-inflammatory cytokines for disease severity and coagulation in septic patients with bacterial co-infection.

METHODS

A total of 92 patients with sepsis admitted to intensive care unit (ICU) from January 2017 to August 2020 were enrolled and their clinical data were retrospectively analyzed. Forty-seven patients (51.1%) had a single infection by Klebsiella pneumoniae or Acinetobacter baumannii (single-infection group), and 45 patients (48.9%) were infected by both species (co-infection group). We compared the clinical characteristics and disease severity among the 92 patients. Disease severity was defined as ICU stay time and 30-day mortality. Plasma concentrations of pro-inflammatory cytokines and their correlation with disease severity and blood coagulation were analyzed.

RESULTS

The 30-day mortality in the co-infection group (35.5%) was significantly higher than in the single-infection group (19.1%). The levels of IL-6 and TNF-α in the co-infection group were higher than in the single-infection group. Moreover, high levels of IL-6, IL-8, and TNF-α were positively correlated with disease severity (Spearman P value < 0.05). High levels of IL-6 and TNF-α were negatively correlated with the platelet count (Spearman P value < 0.05) and positively correlated with prothrombin time, and plasma levels of fibrin degradation product and D-dimer levels (Spearman P value < 0.05 for all).

CONCLUSION

Septic patients with bacterial co-infection had increased plasma levels of pro-inflammatory cytokines. Furthermore, a positive correlation between high levels of pro-inflammatory cytokines and increased disease severity and depressed blood coagulation function for septic patients with co-infection was identified.

Clinical Outcome Prediction in COVID-19 Patients by Lymphocyte Subsets Analysis and Monocytes' iTNF-α Expression

In December 2019, a novel coronavirus, "SARS-CoV-2", was recognized as the cause of coronavirus disease 2019 (COVID-19). Several studies have explored the changes and the role of inflammatory cells and cytokines in the immunopathogenesis of the disease, but until today, the results have been controversial. Based on these premises, we conducted a retrospective assessment of monocyte intracellular TNF-α expression (iTNF-α) and on the frequencies of lymphocyte sub-populations in twenty-five patients with moderate/severe COVID-19. We found lymphopenia in all COVID-19 infected subjects compared to healthy subjects. On initial observation, in patients with favorable outcomes, we detected a high absolute eosinophil count and a high CD4+/CD8+ T lymphocytes ratio, while in the Exitus Group, we observed high neutrophil and CD8+ T lymphocyte counts. During infection, in patients with favorable outcomes, we observed a rise in the lymphocyte count, in the monocyte and in Treg lymphocyte counts, and in the CD4+ and in CD8+ T lymphocytes count but a reduction in the CD4+/CD8+ T lymphocyte ratio. Instead, in the Exitus Group, we observed a reduction in the Treg lymphocyte counts and a decrease in iTNF-α expression. Our preliminary findings point to a modulation of the different cellular mediators of the immune system, which probably play a key role in the outcomes of COVID-19.

Towards efficient immunotherapy for bacterial infection

The emergence of multiantibiotic-resistant bacteria, often referred to as superbugs, is leading to infections that are increasingly difficult to treat. Further, bacteria have evolved mechanisms by which they subvert the immune response, meaning that even antibiotic-sensitive bacteria can persist through antibiotic therapy. For these reasons, a broad range of viable therapeutic alternatives or conjunctions to traditional antimicrobial therapy are urgently required to reduce the burden of disease threatened by antibiotic resistance. Immunotherapy has emerged as a leading treatment option in cancer, and researchers are now attempting to apply this to infectious disease. This review summarizes and discusses the recent advances in the field and highlights current and future perspectives of using immunotherapies to treat bacterial infections.