Activation Of Inflammatory Cells Research Articles

Butyrate suppresses experimental necrotizing enterocolitis-induced brain injury in mice.

Necrotizing enterocolitis (NEC) is a devastating disease in premature infants, and 50% of infants with surgical NEC develop neurodevelopmental defects. The mechanisms by which NEC-induced cytokine release and activation of inflammatory cells in the brain mediate neuronal injury, and whether enteral immunotherapy attenuates NEC-associated brain injury remain understudied. Based on our prior work, which demonstrated that experimental NEC-like intestinal injury is attenuated by the short-chain fatty acid, butyrate, in this study, we hypothesize that NEC-induced brain injury would be suppressed by enteral butyrate supplementation. A standardized NEC mouse model [enteral formula feeding, lipopolysaccharide (LPS), and hypoxia] was used. Mice were randomized into the following groups: control, NEC, butyrate pretreated NEC, and butyrate control. NEC scoring (1-4 with 4 representing severe injury) was performed on ileal sections using a validated scoring system. Intestinal and brain lysates were used to assess inflammation, proinflammatory signaling, and apoptosis. NEC-induced intestinal injury was attenuated by butyrate supplementation. NEC-induced microglial activation in the cerebral cortex and hippocampus was suppressed with butyrate. NEC increased the number of activated microglial cells but decreased the number of oligodendrocytes. Butyrate pretreatment attenuated these changes. Increased activation of proinflammatory Toll-like receptor signaling, cytokine expression, and induction of GFAP and IBA1 in the cerebral cortex observed with NEC was suppressed with butyrate. Experimental NEC induced inflammation and activation of microglia in several regions of the brain, most prominently in the cortex. NEC-induced neuroinflammation was suppressed with butyrate pretreatment. The addition of short-chain fatty acids to diet may be used to attenuate NEC-induced intestinal injury and neuroinflammation in preterm infants.

Novel tripeptide RKH derived from Akkermansia muciniphila protects against lethal sepsis

ObjectiveThe pathogenesis of sepsis is complex, and the sepsis-induced systemic proinflammatory phase is one of the key drivers of organ failure and consequent mortality. Akkermansia muciniphila (AKK) is recognised as...

Identification of Candidate Genes Associated With Development of Vascular Cognitive Impairment by Integrated Bioinformatics Analysis Combined With Biological Experiments.

The morbidity and mortality associated with vascular cognitive impairment (VCI) generally increase steeply, and health systems will face increasing demand for services. The present study aims to screen key genes to give new insight into the mechanisms and treatment of VCI based on bioinformatic approaches combined with biological experiments in rats. The gene expression data of VCI patients contained in the GSE122063 data set were downloaded from the Gene Expression Omnibus. We performed a weighted gene co-expression network analysis to identify a hub module and 44 hub genes. Two hundred and seventy-seven differentially expressed genes (DEGs) were analyzed using R software by the "limma" package. STRING database was used to construct protein-protein interaction (PPI) network, after which 36 hub genes were identified through Cytoscape. Functional enrichment analysis revealed that these genes from the yellow module and 277 DEGs were mainly associated with these pathways, such as Staphylococcus aureus infection, complement, and coagulation cascades. These biological functions are related to inflammatory cell activation and inflammatory response. The key genes of VCI were the overlapping hub genes from the yellow module and the PPI network. The expressions of hub genes in rats were determined by quantitative reverse transcription-polymerase chain reaction, Western blot, immunohistochemistry, and immunofluorescence. In conclusion, C1QA, C1QB, C1QC, CD163, and FCGR2A were highly expressed in the hippocampus of VCI rats, and they can serve as candidate biomarkers for the diagnosis and prognosis of VCI. Finally, molecular docking results suggested that 5 genes interact with Bisphenol A. These findings open a new avenue to investigate molecular mechanisms for preventing or treating VCI.

Aging and Inflammation.

Aging can be conceptualized as the progressive disequilibrium between stochastic damage accumulation and resilience mechanisms that continuously repair that damage, which eventually cause the development of chronic disease, frailty, and death. The immune system is at the forefront of these resilience mechanisms. Indeed, aging is associated with persistent activation of the immune system, witnessed by a high circulating level of inflammatory markers and activation of immune cells in the circulation and in tissue, a condition called "inflammaging." Like aging, inflammaging is associated with increased risk of many age-related pathologies and disabilities, as well as frailty and death. Herein we discuss recent advances in the understanding of the mechanisms leading to inflammaging and the intrinsic dysregulation of the immune function that occurs with aging. We focus on the underlying mechanisms of chronic inflammation, in particular the role of NF-κB and recent studies targeting proinflammatory mediators. We further explore the dysregulation of the immune response with age and immunosenescence as an important mechanistic immune response to acute stressors. We examine the role of the gastrointestinal microbiome, age-related dysbiosis, and the integrated stress response in modulating the inflammatory "response" to damage accumulation and stress. We conclude by focusing on the seminal question of whether reducing inflammation is useful and the results of related clinical trials. In summary, we propose that inflammation may be viewed both as a clinical biomarker of the failure of resilience mechanisms and as a causal factor in the rising burden of disease and disabilities with aging. The fact that inflammation can be reduced through nonpharmacological interventions such as diet and exercise suggests that a life course approach based on education may be a successful strategy to increase the health span with few adverse consequences.

Mechanism of simulated lunar dust-induced lung injury in rats based on transcriptomics.

Lunar dust particles are an environmental threat to lunar astronauts, and inhalation of lunar dust can cause lung damage. The current study explored the mechanism of lunar dust simulant (CLDS-i) inducing inflammatory pulmonary injury. Wistar rats were exposed to CLDS-i for 4 h/d and 7d/week for 4 weeks. Pathological results showed that a large number of inflammatory cells gathered and infiltrated in the lung tissues of the simulated lunar dust group, and the alveolar structures were destroyed. Transcriptome analysis confirmed that CLDS-i was mainly involved in the regulation of activation and differentiation of immune inflammatory cells, activated signaling pathways related to inflammatory diseases, and promoted the occurrence and development of inflammatory injury in the lung. Combined with metabolomics analysis, the results of joint analysis of omics were found that the genes Kmo, Kynu, Nos3, Arg1 and Adh7 were involved in the regulation of amino acid metabolism in rat lung tissues, and these genes might be the key targets for the treatment of amino acid metabolic diseases. In addition, the imbalance of amino acid metabolism might be related to the activation of nuclear factor kappaB (NF-κB) signaling pathway. The results of quantitative real-time polymerase chain reaction and Western blot further confirmed that CLDS-i may promote the occurrence and development of lung inflammation and lead to abnormal amino acid metabolism by activating the B cell activation factor (BAFF)/ B cell activation factor receptor (BAFFR)-mediated NF-κB signaling pathway.

Investigation of inflammation in Lewy body dementia: a scoping review

AbstractBackgroundInflammatory mechanisms are increasingly recognized as part of the pathogenesis of neurodegenerative diseases, including Lewy body dementia (LBD). Advances in analytical techniques using in vivo and postmortem samples have been applied to address questions of key mechanisms and relevance to clinical manifestations. Our primary objective was to review methods used to investigate inflammation in LBD (dementia with Lewy bodies and Parkinson’s disease dementia), and how these are applied to conceptualise inflammation. Our secondary objective was to identify alterations in inflammatory signals in LBD compared to people without neurodegenerative disease, and compared to related neurodegenerative disease, in particular AD and PD.MethodA scoping review was performed by identifying relevant human studies that investigated inflammation in LBD. The major electronic databases MEDLINE, Embase, Web of Science, and PSYCHInfo were searched. Two authors performed abstract screening and full text review.ResultOf 1970 results screened, 65 studies were included. Twenty‐nine studies analysed postmortem brain tissue and 35 included living subjects. Largely cross‐sectional data were available, although 2 longitudinal clinical studies of prodromal Lewy body disease were noted. Analysis of biofluid (blood and cerebrospinal fluid) was the most common in vivo method used (n = 31) and 3 studies investigated LBD genetics. Investigations were focused on inflammatory immune cell activity (microglia, astrocytes, lymphocytes), and molecules linked to inflammation (e.g., cytokines). Results of included studies supported innate and adaptive immune system contribution to inflammation associated with Lewy body pathology and clinical features of the disease. Different signals in early and late‐stage disease, with possible late immune senescence including dystrophic microglia and altered adaptive immunity, were distinct from Alzheimer’s disease. The strength of these associations is limited by the varying methodologies, small study sizes and cross‐sectional nature of data.ConclusionCurrent investigation of inflammation in LBD utilises substrate collected from early to late‐stage disease. Strengths and limitations of the range of analytical techniques used must be considered when forming conclusions. Longitudinal data that informs associations with clinical and other biomarker outcomes is needed to improve understanding of inflammatory activity over the disease course of LBD. This could identify markers of disease activity and therapeutic targets.

Investigating two pore potassium channel THIK‐1 expression in Alzheimer’s disease

AbstractBackgroundThe neuroinflammatory response, particularly the activation of the NLRP3 pathway, has been suggested as one of the key mechanisms of the pathological process in neurodegenerative diseases. Tandem pore domain halothane‐inhibited K+ channel 1 (THIK‐1) provides an upstream regulation of this neuroinflammatory response by modulating intracellular K+. While in vitro and in vivo model systems provide strong support for these mechanisms, unequivocal evidence from neurodegenerative disorders has been lacking.MethodThis research project investigated gene expression of markers in the THIK‐1/NLRP3 pathway by studying post‐mortem brain tissue of animal model representing Alzheimer’s disease (AD). In addition, THIK‐1 gene and protein expression in human post‐mortem brains of AD and Parkinson’s disease (PD) was investigated. Furthermore, DNA methylation of THIK‐1 gene in human post‐mortem brains of AD was analysed to explore a potential underlying mechanism of the changes of THIK‐1 gene expression.ResultA rat model of AD pathogenesis by intrahippocampal Aβ oligomer injection showed substantial up regulation of THIK‐1, glial activation markers, NLRP3 inflammasome components and IL‐1β. Changes in cortical gene expression for THIK‐1 support an inflammatory glial cell activation in both advanced AD and PD with dementia, not observed in the substantia nigra of the latter group. The increase in THIK‐1 expression was also supported by down‐regulation in DNA methylation of its corresponding gene in AD.ConclusionThe association between THIK‐1 expression and pathology changes observed in this study indicate a THIK‐1‐induced activation of this glial subtype in AD and PD. Therefore, specific blocks of the microglial THIK‐1 K+ channels at the early stage of AD and PD provides a potential therapeutic target.

Anti‐Inflammatory Nanotherapies Based on Bioactive Cyclodextrin Materials

Despite remarkable advances in understanding the mechanisms underlying inflammation, the currently available anti‐inflammatory therapies have many limitations, such as poor efficacies, low selectivity, and severe adverse effects. Bioactive materials with intrinsically anti‐inflammatory activities have emerged as promising drug candidates for the treatment of inflammatory disorders. Among them, nanotherapies based on bioactive cyclodextrin (CD) materials have attracted much attention, owing to their multiple advantages, including broad availability, well‐controlled structures, easy functionalization, good processibility, high cost‐effectiveness, and excellent biocompatibility. This review provides a comprehensive overview of the recent advancements in the development and applications of anti‐inflammatory nanoparticles (NPs) based on bioactive CD materials, with special focus on reactive oxygen species‐scavenging NPs and NPs capable of regulating inflammatory cell recruitment and activation. In addition, the applications of these anti‐inflammatory nanotherapies in the treatment of different acute/chronic inflammatory diseases are highlighted. Furthermore, major challenges in the clinical translation of these new generation anti‐inflammatory therapies derived from bioactive CD materials are discussed.

Cardiac reprogramming reduces inflammatory macrophages and improves cardiac function in chronic myocardial infarction

Cardiomyocytes (CMs) have little regenerative capacity. After myocardial infarction (MI), scar formation and myocardial remodeling proceed in the infarct and non-infarct areas, respectively, leading to heart failure (HF). Prolonged activation of cardiac fibroblasts (CFs) and inflammatory cells may contribute to this process; however, therapies targeting these cell types remain lacking. Cardiac reprogramming converts CFs into induced CMs, reduces fibrosis, and improves cardiac function in chronic MI through the overexpression of Mef2c/Gata4/Tbx5/Hand2 (MGTH). However, whether cardiac reprogramming reduces inflammation in infarcted hearts remains unclear. Moreover, the mechanism through which MGTH overexpression in CFs affects inflammatory cells remains unknown. Here, we showed that inflammation persists in the myocardium until three months after MI, which can be reversed with cardiac reprogramming. Single-cell RNA sequencing demonstrated that CFs expressed pro-inflammatory genes and exhibited strong intercellular communication with inflammatory cells, including macrophages, in chronic MI. Cardiac reprogramming suppressed the inflammatory profiles of CFs and reduced the relative ratios and pro-inflammatory signatures of cardiac macrophages. Moreover, fluorescence-activated cell sorting analysis (FACS) revealed that cardiac reprogramming reduced the number of chemokine receptor type 2 (CCR2)-positive inflammatory macrophages in the non-infarct areas in chronic MI, thereby restoring myocardial remodeling. Thus, cardiac reprogramming reduced the number of inflammatory macrophages to exacerbate cardiac function after MI.

The impact of aging and oxidative stress in metabolic and nervous system disorders: programmed cell death and molecular signal transduction crosstalk.

Life expectancy is increasing throughout the world and coincides with a rise in non-communicable diseases (NCDs), especially for metabolic disease that includes diabetes mellitus (DM) and neurodegenerative disorders. The debilitating effects of metabolic disorders influence the entire body and significantly affect the nervous system impacting greater than one billion people with disability in the peripheral nervous system as well as with cognitive loss, now the seventh leading cause of death worldwide. Metabolic disorders, such as DM, and neurologic disease remain a significant challenge for the treatment and care of individuals since present therapies may limit symptoms but do not halt overall disease progression. These clinical challenges to address the interplay between metabolic and neurodegenerative disorders warrant innovative strategies that can focus upon the underlying mechanisms of aging-related disorders, oxidative stress, cell senescence, and cell death. Programmed cell death pathways that involve autophagy, apoptosis, ferroptosis, and pyroptosis can play a critical role in metabolic and neurodegenerative disorders and oversee processes that include insulin resistance, β-cell function, mitochondrial integrity, reactive oxygen species release, and inflammatory cell activation. The silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), AMP activated protein kinase (AMPK), and Wnt1 inducible signaling pathway protein 1 (WISP1) are novel targets that can oversee programmed cell death pathways tied to β-nicotinamide adenine dinucleotide (NAD+), nicotinamide, apolipoprotein E (APOE), severe acute respiratory syndrome (SARS-CoV-2) exposure with coronavirus disease 2019 (COVID-19), and trophic factors, such as erythropoietin (EPO). The pathways of programmed cell death, SIRT1, AMPK, and WISP1 offer exciting prospects for maintaining metabolic homeostasis and nervous system function that can be compromised during aging-related disorders and lead to cognitive impairment, but these pathways have dual roles in determining the ultimate fate of cells and organ systems that warrant thoughtful insight into complex autofeedback mechanisms.

The transcription factor ELF4 alleviates inflammatory bowel disease by activating IL1RN transcription, suppressing inflammatory TH17 cell activity, and inducing macrophage M2 polarization.

Inflammatory bowel disease (IBD) is a chronic immune-mediated disorder affecting millions worldwide. Due to the complexity of its pathogenesis, the treatment options for IBD are limited. This study focuses on ELF4, a member of the ETS transcription factor family, as a target to elucidate its role in IBD and investigate its mechanism of action in alleviating IBD symptoms by activating IL1RN transcription to suppress the activity of inflammatory TH17 cells. Using the GEO database, this study examined LPS-induced intestinal inflammatory genes and their regulation mechanisms. We examined the colon length of LPS-treated mice and derived the Disease Activity Index (DAI). H&E staining, ELISA, and flow cytometry were used to detect mice colon tissue damage, inflammatory factor levels in mouse serum, mouse macrophage types and inflammatory TH17 cell activity. RT-qPCR and Western blot detected ELF4, IL1RN, M1, and M2 polarization markers. In Vitro, using dual-luciferase and ChIP assays, we tested mouse bone marrow-derived macrophages (BMDMs) and mouse intestinal epithelial cells for IL1RN promoter activity and ELF4 enrichment. Bioinformatics showed that LPS-induced colitis animals have reduced ELF4 expression in their colon tissue. In vivo tests confirmed reduced ELF4 expression in mice with LPS-induced colitis. ELF4 overexpression reduced mouse intestinal inflammation. ELF4 activated IL1RN transcription in bioinformatics and in vitro tests. ELF4 promoted IL1RN transcription and macrophage M2 polarization to limit intestinal epithelial cell death and inflammation and reduce mouse intestinal inflammation in vitro. ELF4 also reduced the Th17/Treg ratio by increasing IL1RN transcription. ELF4 activates IL1RN transcription, suppresses inflammatory TH17 cells, and induces macrophage M2 polarization to treat IBD.

PSV-25 Effect of Garlic on Galectin 3 in Goats

Abstract The objective of this study was to determine the effect of garlic extracts on expression of Galectin 3 in goats. Inflammatory diseases such as mastitis and gastrointestinal parasitic diseases cause significant problems for goat production. Galectins (Gal) are a family of highly conserved mammalian carbohydrate-binding proteins that can regulate inflammation. Galectin-3 is the only member of the lectin family with a chimeric structure. It is a potential therapeutic target to regulate the activity of inflammatory cells. Garlic extracts are natural anti-inflammatory agents that are being evaluated for use in goat management. Twelve adult female clinically healthy Boer X Spanish goats were divided into 2 groups. The treatment group (n = 6) was drenched with a 10 mL garlic (Garlic barrier) and the control group (n = 6) was given sterile water for 30 days. Blood was collected weekly from the jugular vein using acid citrate dextrose as an anticoagulant. Blood was centrifuged to separate cells and plasma. Galectin 3 secretion in plasma was determined using goat specific commercial ELISA kits (My-BioSource). Total RNA was isolated from the cell pellet using Trizol and it was then converted into cDNA. Primers specific for goat Gal 3 specific and the housekeeping genes RPLP0 and UCHL5 (Eurofins Genomics) were used in Real-time PCR to evaluate the gene expression. Fold change was calculated using the Livak method. All variables were assessed using SAS Statistical analysis software version 9.4 (SAS Institute) at P < 0.05. Treatment had an effect over time and a significant increase (P < 0.0141) was observed in the GAL- 3 concentrations. Gal-3 was expressed in greater amounts in treatment group animals compared with the control group with a fold change of 1.15. Garlic may be used to modulate Gal 3 expression and secretion in goat blood. It is important to consider the impact of garlic on Gal 3 modulation. Studies needed to define possible impacts on immune function and goat health.

Investigation of CD83 As a Novel Human Hematopoietic Stem Cell Inflammatory Activation Marker

Hematopoietic stem cells (HSC) are responsible for life-long blood production and must balance homeostasis with sudden demand situations such as infections. However, the heterogeneity of molecular programs engaged by acute inflammatory stimuli to activate emergency hematopoiesis at the level of HSC are poorly understood. In a recent study linking human HSC heterogeneity to aging, recovery from severe COVID-19 infection, and clonal hematopoiesis (CH), we discovered two HSC subsets through multiomic analysis, denoted HSC-I and -II, in a xenograft model of inflammation-recovery. While HSC-I had few inflammation-driven molecular changes, HSC-II showed sustained epigenetic and transcriptional alterations in response to dual tumor necrosis factor α (TNFα) or lipopolysaccharide (LPS) challenges despite a 2.5-month recovery period. Importantly, a signature of long-term memory T cells (Akondy et al 2017) was enriched in HSC-II (Zeng, Nagree, et al, in submission). We interrogated the human HSC multiomic signatures uncovered from this human xenograft model to identify potential regulators associated with HSC response to and recovery from acute inflammation. We identified CD83 as a candidate that is differentially expressed between our HSC subsets. Similarly, we found CD83 expression to be enriched in a subset of adult-derived HSCs from patients where CH status was established and enrichment of an HSC-II signature observed (Jakobsen et al, submitted). CD83, first identified as a dendritic cell marker, is expressed on many immune cells, with linkage to controlling murine T regulatory (T-Reg) vs memory cell fate (Doebbeler et al, 2018), but has not previously been shown to be relevant for human HSC biology. Flow cytometry analysis of cord blood (CB) hematopoietic stem and progenitor cells (HSPC) showed CD83 to be low or absent in HSC (Figure A) and their downstream progeny at steady state. However, robust CD83 expression was observed in multiple HSPC subpopulations including long-term (LT-) and short-term (ST-) HSC within 16 hours of ex vivo culture, with highest expression in LT-HSC (Figure A). Importantly, CD83 surface expression on LT-HSC was enhanced following culture with TNFα (Figure A). Bystander effects were excluded by demonstrating similar findings after culture of purified HSC populations. Acute in vivo LPS treatment of mice xenografted with CB-derived HSC was sufficient to upregulate CD83 surface expression after 16 hours on LT-HSC/HSPC. To elucidate the potential function of CD83-expressing HSC/multipotent progenitors (MPP), CD19-CD34+CD38-CD45RA- cells were sorted from xenografts following acute inflammatory challenge for low and high CD83 expression and subjected to bulk RNA sequencing. We found enrichment of a gene expression signature specific to activated human HSCs (Garcia-Prat et al, 2021) within CD83-positive HSC/MPP (Figure B). Strikingly, enrichment of a signature of stimulated vs resting T cells (Galetti et al, 2020) and of effector T cells (Akondy et al 2017) was found in CD83-positive compared to CD83-negative HSC/MPP (Figure B). T cell effector function is in part dictated by metabolic reprogramming. We thus examined reactive oxygen species (ROS) levels in LT-HSC following ex vivo culture with TNFα and found lower ROS levels with CD83 expression. We therefore hypothesize that CD83 may be an ‘effector’ marker defining a distinct HSC subset during homeostatic or inflammatory activation that is subsequently fated to become memory-like HSC-II. We are undertaking studies to determine the mechanistic role of CD83 in HSC function and HSC-II formation via Cas9-sgRNA-mediated knockout or lentivirus-mediated overexpression of CD83. In summary, CD83 represents a long-sought marker of inflammatory activation at the HSC level. CD83 may have significant clinical potential as a biomarker of aberrant activation in gene therapy manufacturing protocols or for HSC transplantation. Future studies will shed light on whether CD83 can functionally regulate the molecular programs underlying human HSC heterogeneity.

Human PBMCs Form Lipid Droplets in Response to Spike Proteins.

Intracellular lipid droplets (LDs) can accumulate in response to inflammation, metabolic stresses, and other physiological/pathological processes. Herein, we investigated whether spike proteins of SARS-CoV-2 induce LDs in human peripheral blood mononuclear cells (PBMCs) and in pulmonary microvascular endothelial cells (HPMECs). PBMCs or HPMECs were incubated alone or with endotoxin-free recombinant variants of trimeric spike glycoproteins (Alpha, Beta, Delta, and Omicron, 12 µg/mL). Afterward, cells were stained with Oil Red O for LDs, cytokine release was determined through ELISA, and the gene expression was analyzed through real-time PCR using TaqMan assays. Our data show that spikes induce LDs in PBMCs but not in HPMECs. In line with this, in PBMCs, spike proteins lower the expression of genes involving lipid metabolism and LD formation, such as SREBF1, HMGCS1, LDLR, and CD36. On the other hand, PBMCs exposed to spikes for 6 or 18 h did not increase in IL-1β, IL-6, IL-8, MCP-1, and TNFα release or expression as compared to non-treated controls. Thus, spike-induced LD formation in PBMCs seems to not be related to cell inflammatory activation. Further detailed studies are warranted to investigate in which specific immune cells spikes induce LDs, and what are the pathophysiological mechanisms and consequences of this induction in vivo.

Central and peripheral mechanism of MOTS-c attenuates pain hypersensitivity in a mice model of inflammatory pain

ABSTRACT Background Inflammatory pain is caused by damaged tissue or noxious stimuli, accompanied by the release of inflammatory mediators that often leads to severe hyperalgesia and allodynia with limited therapy options. Recently, a novel mitochondrial-derived peptide (named MOTS-c) was reported to regulate obesity, metabolic homeostasis and inflammatory response. The aim of this study was to investigate the effects of MOTS-c and its related regulatory mechanisms involved in inflammatory pain. Methods Male Kunming mice (8–10 weeks-old) were intraplantar injected with formalin, capsaicin, λ-Carrageenan and complete Freund adjuvant (CFA) to establish acute and chronic inflammatory pain. The effects of MOTS-c on the above inflammatory pain mice and its underlying mechanisms were examined by behavioral tests, quantitative polymerase chain reaction (qPCR), western blotting, enzyme linked immunosorbent assay (ELISA), immunohistochemistry (IHC) and immunofluorescence (IF). Results Behavioral experiments investigated the potential beneficial effects of MOTS-c on multiple acute and chronic inflammatory pain in mice. The results showed that MOTS-c treatment produced potent anti-allodynic effects in formalin-induced acute inflammatory pain, capsaicin-induced nocifensive behaviors and λ-Carrageenan/CFA-induced chronic inflammatory pain model. Further mechanistic studies revealed that central MOTS-c treatment significantly ameliorated CFA-evoked the release of inflammatory factors and activation of glial cells and neurons in the spinal dorsal horn. Moreover, peripheral MOTS-c treatment reduced CFA-evoked inflammatory responses in the surface structure of hindpaw skin, accompanied by inhibiting excitation of peripheral calcitonin gene-related peptide (CGRP) and P2X3 nociceptive neurons. Conclusions The present study indicates that MOTS-c may serve as a promising therapeutic target for inflammatory pain.

Panax quinquefolium saponins attenuates microglia activation following acute cerebral ischemia-reperfusion injury via Nrf2/miR-103-3p/TANK pathway.

Ischemic stroke is one of the leading causes of death and disability among adults worldwide. Intravenous thrombolysis is the only approved pharmacological treatment for acute ischemic stroke. However, reperfusion by thrombolysis will lead to the rapid activation of microglia cells which induces interferon-inflammatory response in the ischemic brain tissues. Panax quinquefolium saponins (PQS) has been proven to be effective in acute ischemic stroke, but there is no unified understanding about its specific mechanism. Here, we will report for the first time that PQS can significantly inhibit the activation of microglia cells in cerebral of MCAO rats via activation of Nrf2/miR-103-3p/TANKaxis. Our results showed that PQS can directly bind to Nrf2 protein and inhibit its ubiquitination, which result in the indirectly enhancing the expression of TANK protein via transcriptional regulation on miR-103-3p, and finally to suppress the nuclear factor kappa-B dominated rapid activation of microglial cells induced by oxygen-glucose deprivation/reoxygenationvitro and cerebral ischemia-reperfusion injury in vivo. In conclusion, our study not only revealed the new mechanism of PQS in protecting against the inflammatory activation of microglia cells caused by cerebral ischemia-reperfusion injury, but also suggested that Nrf2 is a potential target for development of new drugs of ischemic stroke. More importantly, our study also reminded that miR-103-3p might be used as a prognostic biomarker for patients with ischemic stroke.

Functional integration of natural killer cells in a microfluidically perfused liver on-a-chip model

ObjectiveThe liver acts as an innate immunity-dominant organ and natural killer (NK) cells, are the main lymphocyte population in the human liver. NK cells are in close interaction with other immune cells, acting as the first line of defense against pathogens, infections, and injury.A previously developed, three-dimensional, perfused liver-on-a-chip comprised of human cells was used to integrate NK cells, representing pivotal immune cells during liver injury and regeneration. The objective of this study was to integrate functional NK cells in an in vitro model of the human liver and assess utilization of the model for NK cell-dependent studies of liver inflammation.ResultsNK cells from human blood and liver specimen were isolated by Percoll separation with subsequent magnetic cell separation (MACS), yielding highly purified blood and liver derived NK cells. After stimulation with toll-like-receptor (TLR) agonists (lipopolysaccharides, Pam3CSK4), isolated NK cells showed increased interferon (IFN)-gamma secretion. To study the role of NK cells in a complex hepatic environment, these cells were integrated in the vascular compartment of a microfluidically supported liver-on-a-chip model in close interaction with endothelial and resident macrophages. Successful, functional integration of NK cells was verified by immunofluorescence staining (NKp46), flow cytometry analysis and TLR agonist-dependent secretion of interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha. Lastly, we observed that inflammatory activation of NK cells in the liver-on-a-chip led to a loss of vascular barrier integrity. Overall, our data shows the first successful, functional integration of NK cells in a liver-on-a-chip model that can be utilized to investigate NK cell-dependent effects on liver inflammation in vitro.

GAS-STING: a classical DNA recognition pathways to tumor therapy.

Cyclic GMP-AMP synthetase (cGAS), recognized as the primary DNA sensor within cells, possesses the capability to identify foreign DNA molecules along with free DNA fragments. This identification process facilitates the production of type I IFNs through the activator of the interferon gene (STING) which induces the phosphorylation of downstream transcription factors. This action characterizes the most archetypal biological functionality of the cGAS-STING pathway. When treated with anti-tumor agents, cells experience DNA damage that triggers activation of the cGAS-STING pathway, culminating in the expression of type I IFNs and associated downstream interferon-stimulated genes. cGAS-STING is one of the important innate immune pathways,the role of type I IFNs in the articulation between innate immunity and T-cell antitumour immunity.type I IFNs promote the recruitment and activation of inflammatory cells (including NK cells) at the tumor site.Type I IFNs also can promote the activation and maturation of dendritic cel(DC), improve the antigen presentation of CD4+T lymphocytes, and enhance the cross-presentation of CD8+T lymphocytes to upregulating anti-tumor responses. This review discussed the cGAS-STING signaling and its mechanism and biological function in traditional tumor therapy and immunotherapy.

Biochemical Changes in Cardiopulmonary Bypass in Cardiac Surgery: New Insights.

Patients undergoing coronary revascularization with extracorporeal circulation or cardiopulmonary bypass (CPB) may develop several biochemical changes in the microcirculation that lead to a systemic inflammatory response. Surgical incision, post-CPB reperfusion injury and blood contact with non-endothelial membranes can activate inflammatory signaling pathways that lead to the production and activation of inflammatory cells, with cytokine production and oxidative stress. This inflammatory storm can cause damage to vital organs, especially the heart, and thus lead to complications in the postoperative period. In addition to the organic pathophysiology during and after the period of exposure to extracorporeal circulation, this review addresses new perspectives for intraoperative treatment and management that may lead to a reduction in this inflammatory storm and thereby improve the prognosis and possibly reduce the mortality of these patients.

Elevated Expression of Two Pore Potassium Channel THIK-1 in Alzheimer's Disease: An Inflammatory Mechanism.

Tandem pore domain halothane-inhibited K+ channel 1 (THIK-1, coded by KCNK13) provides an upstream regulation of the activation of the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome, which has been suggested as one of the key mechanisms of the pathological process in neurodegeneration mainly from in vitro and in vivo model systems studies. However, unequivocal evidence from neurodegenerative disorders has been lacking. To investigate the involvement of the THIK-1/NLRP3 pathway in the pathological process of Alzheimer's disease (AD) and Parkinson's disease (PD). This study investigated gene expression of markers in the THIK-1/NLRP3 pathway in an animal model representing AD as well as in human postmortem brains of AD and PD by quantitative real-time PCR. THIK-1 protein expression was determined using automated capillary electrophoresis immunoblotting. Furthermore, DNA methylation of KCNK13 was analysed in AD cohort by pyrosequencing. A substantial upregulation of KCNK13, glial activation markers, NLRP3 inflammasome components, and IL1B was observed in the animal study. Increased expression of KCNK13 support an inflammatory glial cell activation in both advanced AD and PD. The increase in KCNK13 expression was also supported by downregulation in DNA methylation of KCNK13 in AD. The association between THIK-1 K+ channels expression and pathology changes indicates a THIK-1-induced activation of this glial subtype in AD and PD. Therefore, specific blocks of the microglial THIK-1 K+ channels at the early stage of AD and PD may be beneficial for the patients.