Early innate immune responses to bacterial LPS

Subchronic intranasal lipopolysaccharide exposure induces pulmonary autoimmunity and glomerulonephritis in NZBWF1 mice

Lupus, a systemic autoimmune disease shaped by gene-environment interplay, often progresses to endstage renal failure. While subchronic systemic exposure to bacterial lipopolysaccharide (LPS) triggers autoimmunity and glomerulonephritis in lupus-prone mice, it is unknown if inhaling LPS, which is common in certain occupations, can similarly trigger lupus. Here we determined how subchronic intranasal (IN) LPS instillation influences autoimmunity and glomerulonephritis development in lupusprone NZBWF1 female mice. Briefly, mice were IN-instilled with vehicle or E. coli LPS (0.8 μg/g) twice weekly for 5 wk, followed by necropsy. For systemic comparison, additional cohorts of mice were injected with LPS intraperitoneally (IP) using identical doses/timing. Lungs were assessed for inflammatory and autoimmune responses and then related to systemic autoimmunity and glomerulonephritis. IN/LPS exposure induced in the lung: i) leukocyte infiltration, ii)mRNA signatures for cytokines, chemokines, IFN-regulated, and cell death-related genes, iii) ectopic lymphoid tissue formation, and iv)diverse IgM and IgG autoantibodies (AAbs). Pulmonary effects coincided with enlarged spleens, elevated plasma IgG AAbs, and inflamed IgG-containing kidney glomeruli. In contrast, IP/LPS treatment induced systemic autoimmunity and glomerulonephritis without pulmonary manifestations. Taken together, these preclinical findings suggest the lung could serve as a critical nexus for triggering autoimmunity by respirable LPS in genetically predisposed individuals.

Cardiopulmonary bypass and VA-ECMO induced immune dysfunction: common features and differences, a narrative review

Cardiopulmonary bypass (CPB) and veno-arterial extracorporeal membrane oxygenation are critical tools in contemporary cardiac surgery and intensive care, respectively. While these techniques share similar components, their application contexts differ, leading to distinct immune dysfunctions which could explain the higher incidence of nosocomial infections among ECMO patients compared to those undergoing CPB. This review explores the immune modifications induced by these techniques, comparing their similarities and differences, and discussing potential treatments to restore immune function and prevent infections. The immune response to CPB and ECMO involves both humoral and cellular components. The kinin system, complement system, and coagulation cascade are rapidly activated upon blood contact with the circuit surfaces, leading to the release of pro-inflammatory mediators. Ischemia-reperfusion injury and the release of damage-associated molecular patterns further exacerbate the inflammatory response. Cellular responses involve platelets, neutrophils, monocytes, dendritic cells, B and T lymphocytes, and myeloid-derived suppressor cells, all of which undergo phenotypic and functional alterations, contributing to immunoparesis. Strategies to mitigate immune dysfunctions include reducing the inflammatory response during CPB/ECMO and enhancing immune functions. Approaches such as off-pump surgery, corticosteroids, complement inhibitors, leukocyte-depleting filters, and mechanical ventilation during CPB have shown varying degrees of success in clinical trials. Immunonutrition, particularly arginine supplementation, has also been explored with mixed results. These strategies aim to balance the inflammatory response and support immune function, potentially reducing infection rates and improving outcomes. In conclusion, both CPB and ECMO trigger significant immune alterations that increase susceptibility to nosocomial infections. Addressing these immune dysfunctions through targeted interventions is essential to improving patient outcomes in cardiac surgery and critical care settings. Future research should focus on refining these strategies and developing new approaches to better manage the immune response in patients undergoing CPB and ECMO.

Unveiling the molecular mechanisms of Dendrobium officinale polysaccharides on intestinal immunity: An integrated study of network pharmacology, molecular dynamics and in vivo experiments

Intestinal immunity plays a pivotal role in overall immunological defenses, constructing mechanisms against pathogens while maintaining balance with commensal microbial communities. Existing therapeutic interventions may lead to drug resistance and potential toxicity when immune capacity is compromised. Dendrobium officinale, a traditional Chinese medicine, contains components identified to bolster immunity. Employing network pharmacology strategies, this study identified constituents of Dendrobium officinale and their action targets in the TCMSP and Swiss Target Prediction databases, and compared them with intestinal immunity-related targets. Protein-protein interaction networks revealed the core targets of Dendrobium officinale polysaccharides, encompassing key pathways such as cell proliferation, inflammatory response, and immune reactions, particularly in association with the Toll-like receptor 4. Molecular docking and molecular dynamics simulation further confirmed the high affinity and stability between Dendrobium officinale polysaccharides and Toll-like receptor 4. In vivo experiments demonstrated that Dendrobium officinale polysaccharides modulates the expression of Toll-like receptor 4 and its downstream key proteins in the colonic mucosa of mice. Consequently, these findings suggest that Dendrobium officinale polysaccharides may serve as a potential modulator for intestinal immune functions, with its mechanism potentially related to the Toll-like receptor 4.

Origin recognition complex subunit 6 (ORC6) is a key mediator of LPS-induced NFκB activation and the pro-inflammatory response

Lipopolysaccharide (LPS)-activated pro-inflammatory responses play a critical role in sepsis, a life-threatening condition. This study investigates the role of origin recognition complex subunit 6 (ORC6) in LPS responses in macrophages and monocytes. Silencing ORC6 using targeted shRNA significantly reduced LPS-induced expression and production of IL-1β (interleukin-1 beta), TNF-α (tumor necrosis factor alpha), and IL-6 (interleukin-6) in THP-1 human macrophages, peripheral blood mononuclear cells (PBMCs), and bone marrow-derived macrophages (BMDMs). Additionally, ORC6 knockout (KO) via the CRISPR/Cas9 method in THP-1 macrophages inhibited LPS-induced pro-inflammatory responses, while ectopic overexpression of ORC6 enhanced LPS-induced expression and production of pro-inflammatory cytokines. ORC6 is crucial for the activation of the nuclear factor kappa B (NFκB) signaling cascade in macrophages and monocytes. LPS-induced NFκB activation was largely inhibited by ORC6 silencing or KO, but potentiated following ORC6 overexpression. Mechanistically, ORC6 associated with nuclear p65 after LPS stimulation, an interaction necessary for NFκB activation. Overexpression of ORC6 did not recover the reduced pro-inflammatory response to LPS in THP-1 macrophages with silenced p65. Furthermore, the NFκB inhibitor BMS-345,541 nearly eliminated the pro-inflammatory response enhanced by ORC6 overexpression in response to LPS. Further studies revealed that ORC6 depletion inhibited NFκB activation induced by double-stranded RNA (dsRNA) and high mobility group box 1 (HMGB1) in THP-1 macrophages. In vivo experiments demonstrated that macrophage-specific knockdown of ORC6 protected mice from LPS-induced septic shock and inhibited LPS-stimulated production of IL-1β, TNF-α, and IL-6 in mouse serum. ORC6 silencing also inhibited LPS-induced NFκB activation in ex vivo cultured PBMCs following macrophage-specific knockdown of ORC6. These findings highlight ORC6 as a pivotal mediator in LPS-induced NFκB activation and the pro-inflammatory response in sepsis, suggesting that targeting ORC6 could be a novel therapeutic strategy for managing sepsis and related inflammatory conditions.

Exposure to bacterial PAMPs before RSV infection exacerbates innate inflammation and disease via IL-1α and TNF-α

Respiratory syncytial virus (RSV) can cause severe lower respiratory tract infections. Understanding why some individuals get more serious disease may help with diagnosis and treatment. One possible risk factor underlying severe disease is bacterial exposure before RSV infection. Bacterial exposure has been associated with increased respiratory viral-induced disease severity but the mechanism remains unknown. Respiratory bacterial infections or exposure to their pathogen associated molecular patterns (PAMPs) trigger innate immune inflammation, characterised by neutrophil and inflammatory monocyte recruitment and the production of inflammatory cytokines. We hypothesise that these changes to the lung environment alter the immune response and disease severity during subsequent RSV infection. To test this, we intranasally exposed mice to LPS, LTA or Acinetobacter baumannii (an airway bacterial pathogen) before RSV infection and observed an early induction of disease, measured by weight loss, at days 1-3 after infection. Neutrophils or inflammatory monocytes were not responsible for driving this exacerbated weight loss. Instead, exacerbated disease was associated with increased IL-1α and TNF-α, which orchestrated the recruitment of innate immune cells into the lung. This study shows that exposure to bacterial PAMPs prior to RSV infection increases the expression of IL-1α and TNF-α, which dysregulate the immune response resulting in exacerbated disease.

High-fat diet elicits sex-based differences in liver inflammatory cytokines and redox homeostasis

Sex differences in metabolic dysfunction-associated steatotic liver disease (MASLD) have been reported. Oxidative stress and inflammation are involved in the progression of MASLD. Thus, we aimed to evaluate liver redox homeostasis and inflammation in male and female rats fed a high-fat diet (HFD). Male and female Wistar rats were divided into the following groups: standard chow diet (SCD) or HFD during 12 weeks. HFD groups of both sexes had higher hepatocyte injury, with no differences between the sexes. Portal space liver inflammation was higher in females-HFD compared to females-SCD, whereas no differences were observed in males. Lobular inflammation and overall liver inflammation were higher in HFD groups, regardless of sex. TNF-α, IL-6, and IL-1β levels were higher in males-HFD compared to males-SCD, but no differences were observed in females. Catalase activity was higher in males compared to females, with no differences between the SCD and HFD groups of both sexes. Glutathione peroxidase activity was higher in females compared to males, with no differences between the SCD and HFD groups in both sexes. Lipid peroxidation was higher in female-SCD when compared to male-SCD, and in both male- and female-HFD compared to SCD groups. Furthermore, both cytoplasmic and nuclear NRF2 staining were lower in the HFD group compared to the SCD group in males. However, female-HFD exhibited reduced nuclear NRF2 staining compared to the female-SCD group. In conclusion, our study demonstrated that while both male and female rats developed metabolic dysfunction-associated steatohepatitis after 12 weeks of HFD, the alterations in inflammatory cytokines and redox balance were sexually dimorphic.

Semaglutide Attenuates Anxious and Depressive-Like Behaviors and Reverses the Cognitive Impairment in a Type 2 Diabetes Mellitus Mouse Model Via the Microbiota-Gut-Brain Axis

Newly conducted research suggests that metabolic disorders, like diabetes and obesity, play a significant role as risk factors for psychiatric disorders. This connection presents a potential avenue for creating novel antidepressant medications by repurposing drugs originally developed to address antidiabetic conditions. Earlier investigations have shown that GLP-1 (Glucagon-like Peptide-1) analogs exhibit neuroprotective qualities in various models of neurological diseases, encompassing conditions such as Alzheimer's disease, Parkinson's disease, and stroke. Moreover, GLP-1 analogs have demonstrated the capability to enhance neurogenesis, a process recognized for its significance in memory formation and the cognitive and emotional aspects of information processing. Nonetheless, whether semaglutide holds efficacy as both an antidepressant and anxiolytic agent remains uncertain. To address this, our study focused on a mouse model of depression linked to type 2 diabetes induced by a High Fat Diet (HFD). In this model, we administered semaglutide (0.05 mg/Kg intraperitoneally) on a weekly basis to evaluate its potential as a therapeutic option for depression and anxiety. Diabetic mice had higher blood glucose, lipidic profile, and insulin resistance. Moreover, mice fed HFD showed higher serum interleukin (IL)-1β and lipopolysaccharide (LPS) associated with impaired humor and cognition. The analysis of behavioral responses revealed that the administration of semaglutide effectively mitigated depressive- and anxiety-like behaviors, concurrently demonstrating an enhancement in cognitive function. Additionally, semaglutide treatment protected synaptic plasticity and reversed the hippocampal neuroinflammation induced by HFD fed, improving activation of the insulin pathway, demonstrating the protective effects of semaglutide. We also found that semaglutide treatment decreased astrogliosis and microgliosis in the dentate gyrus region of the hippocampus. In addition, semaglutide prevented the DM2-induced impairments of pro-opiomelanocortin (POMC), and G-protein-coupled receptor 43 (GPR43) and simultaneously increased the NeuN + and Glucagon-like Peptide-1 receptor (GLP-1R+) neurons in the hippocampus. Our data also showed that semaglutide increased the serotonin (5-HT) and serotonin transporter (5-HTT) and glutamatergic receptors in the hippocampus. At last, semaglutide changed the gut microbiota profile (increasing Bacterioidetes, Bacteroides acidifaciens, and Blautia coccoides) and decreased leaky gut, improving the gut-brain axis. Taken together, semaglutide has the potential to act as a therapeutic tool for depression and anxiety.

Conservation and similarity of bacterial and eukaryotic innate immunity

Pathogens are ubiquitous and a constant threat to their hosts, which has led to the evolution of sophisticated immune systems in bacteria, archaea and eukaryotes. Bacterial immune systems encode an astoundingly large array of antiviral (antiphage) systems, and recent investigations have identified unexpected similarities between the immune systems of bacteria and animals. In this Review, we discuss advances in our understanding of the bacterial innate immune system and highlight the components, strategies and pathogen restriction mechanisms conserved between bacteria and eukaryotes. We summarize evidence for the hypothesis that components of the human immune system originated in bacteria, where they first evolved to defend against phages. Further, we discuss shared mechanisms that pathogens use to overcome host immune pathways and unexpected similarities between bacterial immune systems and interbacterial antagonism. Understanding the shared evolutionary path of immune components across domains of life and the successful strategies that organisms have arrived at to restrict their pathogens will enable future development of therapeutics that activate the human immune system for the precise treatment of disease.

Gut microbiota: a superior operator for dietary phytochemicals to improve atherosclerosis

Mounting evidence implicates the gut microbiota as a possible key susceptibility factor for atherosclerosis (AS). The employment of dietary phytochemicals that strive to target the gut microbiota has gained scientific support for treating AS. This study conducted a general overview of the links between the gut microbiota and AS, and summarized available evidence that dietary phytochemicals improve AS via manipulating gut microbiota. Then, the microbial metabolism of several dietary phytochemicals was summarized, along with a discussion on the metabolites formed and the biotransformation pathways involving key gut bacteria and enzymes. This study additionally focused on the anti-atherosclerotic potential of representative metabolites from dietary phytochemicals, and investigated their underlying molecular mechanisms. In summary, microbiota-dependent dietary phytochemical therapy is a promising strategy for AS management, and knowledge of "phytochemical-microbiota-biotransformation" may be a breakthrough in the search for novel anti-atherogenic agents.

Slit2-Robo4 signal pathway and tight junction in intestine mediate LPS-induced inflammation in mice

BACKGROUND

Sepsis is one of the most common clinical diseases, which is characterized by a serious and uncontrollable inflammatory response. LPS-induced inflammation is a critical pathological event in sepsis, but the underlying mechanism has not yet been fully elucidated.

METHODS

The animal model was established for two batches. In the first batch of experiments, Adult C57BL/6J mice were randomly divided into control group and LPS (5 mg/kg, i.p.)group . In the second batch of experiments, mice were randomly divided into control group, LPS group, and LPS+VX765(10 mg/kg, i.p., an inhibitor of NLRP3 inflammasome) group. After 24 hours, mice were anesthetized with isoflurane, blood and intestinal tissue were collected for tissue immunohistochemistry, Western blot analysis and ELISA assays.

RESULTS

The C57BL/6J mice injected with LPS for twenty-four hours could exhibit severe inflammatory reaction including an increased IL-1β, IL-18 in serum and activation of NLRP3 inflammasome in intestine. The injection of VX765 could reverse these effects induced by LPS. These results indicated that the increased level of IL-1β and IL-18 in serum induced by LPS is related to the increased intestinal permeability and activation of NLRP3 inflammasome. In the second batch of experiments, results of western blot and immunohistochemistry showed that Slit2 and Robo4 were significant decreased in intestine of LPS group, while the expression of VEGF was significant increased. Meanwhile, the protein level of tight junction protein ZO-1, occludin, and claudin-5 were significantly lower than in control group, which could also be reversed by VX765 injection.

CONCLUSIONS

In this study, we revealed that Slit2-Robo4 signaling pathway and tight junction in intestine may be involved in LPS-induced inflammation in mice, which may account for the molecular mechanism of sepsis.

Activation of angiogenin expression in macrophages by lipopolysaccharide via the TLR4/NF-κB pathway in colitis

Inflammatory bowel disease (IBD) is a debilitating condition that can lead to life-threatening complications. Macrophages are crucial in IBD management because they secrete various cytokines and regulate tissue repair. Macrophage-derived angiogenin (ANG) has been shown to be essential for limiting colonic inflammation, but its upstream regulatory pathway and role in macrophages remain unclear. Here we show that ANG expression is up-regulated in macrophages during colitis treatment or upon lipopolysaccharides (LPS) treatment. Mechanistically, LPS activates Toll-like receptor 4 (TLR4) to initiate NF-κB translocation from the cytoplasm to the nucleus, where it binds to the ANG promoter and enhances its transcriptional activity, leading to increased ANG expression. Interestingly, our data also reveal that the deletion of ANG in macrophages has no adverse effect on key macrophage functions, such as phagocytosis, chemotaxis, and cell survival. Our findings establish a "LPS-TLR4-NF-κB-ANG" regulatory axis in inflammatory disorders and confirm that ANG controls inflammation in a paracrine manner, highlighting the importance of ANG as a key mediator in the complex network of inflammatory processes.

From Gut to Brain: Unraveling the Intricate Link Between Microbiome and Stroke

Stroke, a neurological disorder, is intricately linked to the gut microbiota, influencing microbial composition and elevating the risk of ischemic stroke. The neuroprotective impact of short-chain fatty acids (SCFAs) derived from dietary fiber fermentation contrasts with the neuroinflammatory effects of lipopolysaccharide (LPS) from gut bacteria. The pivotal role of the gut-brain axis, facilitating bidirectional communication between the gut and the brain, is crucial in maintaining gastrointestinal equilibrium and influencing cognitive functions. An in-depth understanding of the interplay among the gut microbiota, immune system, and neurological outcomes in stroke is imperative for devising innovative preventive and therapeutic approaches. Strategies such as dietary adjustments, probiotics, prebiotics, antibiotics, or fecal transplantation offer promise in modulating stroke outcomes. Nevertheless, comprehensive research is essential to unravel the precise mechanisms governing the gut microbiota's involvement in stroke and to establish effective therapeutic interventions. The initiation of large-scale clinical trials is warranted to assess the safety and efficacy of interventions targeting the gut microbiota in stroke management. Tailored strategies that reinstate eubiosis and foster a healthy gut microbiota hold potential for both stroke prevention and treatment. This review underscores the gut microbiota as a promising therapeutic target in stroke and underscores the need for continued research to delineate its precise role and develop microbiome-based interventions effectively.

Interferon inducible guanylate-binding protein 1 modulates the lipopolysaccharide-induced cytokines/chemokines and mitogen-activated protein kinases in macrophages

Guanylate-binding proteins (GBPs) are a family of interferon (IFN)-inducible GTPases and play a pivotal role in the host immune response to microbial infections. These are upregulated in immune cells after recognizing the lipopolysaccharides (LPS), the major membrane component of Gram-negative bacteria. In the present study, the expression pattern of GBP1-7 was initially mapped in phorbol 12-myristate 13-acetate-differentiated human monocytes THP-1 and mouse macrophages RAW 264.7 cell lines stimulated with LPS. A time-dependent significant expression of GBP1-7 was observed in these cells. Moreover, among the various GBPs, GBP1 has emerged as a central player in regulating innate immunity and inflammation. Therefore, to study the specific role of GBP1 in LPS-induced inflammation, knockdown of the Gbp1 gene was carried out in both cells using small interfering RNA interference. Altered levels of different cytokines (interleukin [IL]-4, IL-10, IL-12β, IFN-γ, tumor necrosis factor-α), inducible nitric oxide synthase, histocompatibility 2, class II antigen A, protein kinase R, and chemokines (chemokine (C-X-C motif) ligand 9 [CXCL9], CXCL10, and CXCL11) in GBP1 knockdown cells were reported compared to control cells. Interestingly, the extracellular-signal-regulated kinase 1/2 mitogen-activated protein (MAP) kinases and signal transducer and activator of transcription 1 (STAT1) transcription factor levels were considerably induced in knockdown cells compared to the control cells. However, no change in the level of phosphorylated nuclear factor-kB, c-Jun, and p38 transcription factors was observed in GBP1 knockdown cells compared to the control cells. This study concludes that GBP1 may alter the expression of cytokines, chemokines, and effector molecules mediated by MAP kinases and STAT1 transcription factors.

Controlled production of lipopolysaccharides increases immune activation in Salmonella treatments of cancer

Immunotherapies have revolutionized cancer treatment. These treatments rely on immune cell activation in tumours, which limits the number of patients that respond. Inflammatory molecules, like lipopolysaccharides (LPS), can activate innate immune cells, which convert tumour microenvironments from cold to hot, and increase therapeutic efficacy. However, systemic delivery of lipopolysaccharides (LPS) can induce cytokine storm. In this work, we developed immune-controlling Salmonella (ICS) that only produce LPS in tumours after colonization and systemic clearance. We tuned the expression of msbB, which controls production of immunogenic LPS, by optimizing its ribosomal binding sites and protein degradation tags. This genetic system induced a controllable inflammatory response and increased dendritic cell cross-presentation in vitro. The strong off state did not induce TNFα production and prevented adverse events when injected into mice. The accumulation of ICS in tumours after intravenous injection focused immune responses specifically to tumours. Tumour-specific expression of msbB increased infiltration of immune cells, activated monocytes and neutrophils, increased tumour levels of IL-6, and activated CD8 T cells in draining lymph nodes. These immune responses reduced tumour growth and increased mouse survival. By increasing the efficacy of bacterial anti-cancer therapy, localized production of LPS could provide increased options to patients with immune-resistant cancers.

A Predictive Model of Vaccine Reactogenicity Using Data from an In Vitro Human Innate Immunity Assay System

A primary concern in vaccine development is safety, particularly avoiding an excessive immune reaction in an otherwise healthy individual. An accurate prediction of vaccine reactogenicity using in vitro assays and computational models would facilitate screening and prioritization of novel candidates early in the vaccine development process. Using the modular in vitro immune construct model of human innate immunity, PBMCs from 40 healthy donors were treated with 10 different vaccines of varying reactogenicity profiles and then cell culture supernatants were analyzed via flow cytometry and a multichemokine/cytokine assay. Differential response profiles of innate activity and cell viability were observed in the system. In parallel, an extensive adverse event (AE) dataset for the vaccines was assembled from clinical trial data. A novel reactogenicity scoring framework accounting for the frequency and severity of local and systemic AEs was applied to the clinical data, and a machine learning approach was employed to predict the incidence of clinical AEs from the in vitro assay data. Biomarker analysis suggested that the relative levels of IL-1B, IL-6, IL-10, and CCL4 have higher predictive importance for AE risk. Predictive models were developed for local reactogenicity, systemic reactogenicity, and specific individual AEs. A forward-validation study was performed with a vaccine not used in model development, Trumenba (meningococcal group B vaccine). The clinically observed Trumenba local and systemic reactogenicity fell on the 26th and 93rd percentiles of the ranges predicted by the respective models. Models predicting specific AEs were less accurate. Our study presents a useful framework for the further development of vaccine reactogenicity predictive models.

Decreased toll-like receptor 4 and CD11b/CD18 expression on peripheral monocytes of hypertensive patients correlates with a lesser extent of endothelial damage: a preliminary study

BACKGROUND

Low-grade chronic inflammation is recognized to contribute to the physiopathology of arterial hypertension. Therefore, this study aimed to assess the pro-inflammatory phenotype of peripheral monocytes of hypertensive patients by analyzing Toll-like receptor 4 (TLR4) and CD11b/CD18 surface expression. In the second part, the influence of phenotypic alterations of monocytes on the endothelial status reflected by circulating endothelial cells (CECs) was evaluated.

PATIENTS

The study included 60 patients with arterial hypertension, who were divided into two subgroups based on the disease severity according to the applicable criteria. The mild hypertension and resistant hypertension groups included 30 patients each. The control group consisted of 33 normotensive volunteers matched for age and sex.

RESULTS

Both in the entire group of patients and individual subgroups, reduced surface expression of TLR4 and CD11b/CD18 was found compared to normotensive volunteers. A reduced percentage of monocytes with the CD14 + TLR4 + immunophenotype was correlated with a lower MFI level of CD18 and CD11b in the entire group of patients and after division only in the mild hypertension group. Reduced surface expression of TLR4 in hypertensive patients correlated with a lower number of CECs. This relationship was not observed in the resistant hypertension group; instead, an independent effect of reduced CD11b/CD18 expression on the reduction of CEC number was demonstrated.

CONCLUSION

Our preliminary study showed for the first time that hypertension of varying severity is accompanied by phenotypic changes in monocytes, manifested by reduced surface expression of both TLR4 and CD11b/CD18. These phenotypic changes were associated with a reduced degree of endothelial injury. Our study opens a new, unexplored area of research on the protective features of peripheral monocytes in hypertension.

Dysbiosis of the gut microbiota and its effect on α-synuclein and prion protein misfolding: consequences for neurodegeneration

Abnormal behavior of α-synuclein and prion proteins is the hallmark of Parkinson's disease (PD) and prion illnesses, respectively, being complex neurological disorders. A primary cause of protein aggregation, brain injury, and cognitive loss in prion illnesses is the misfolding of normal cellular prion proteins (PrPC) into an infectious form (PrPSc). Aggregation of α-synuclein causes disruptions in cellular processes in Parkinson's disease (PD), leading to loss of dopamine-producing neurons and motor symptoms. Alteration in the composition or activity of gut microbes may weaken the intestinal barrier and make it possible for prions to go from the gut to the brain. The gut-brain axis is linked to neuroinflammation; the metabolites produced by the gut microbiota affect the aggregation of α-synuclein, regulate inflammation and immunological responses, and may influence the course of the disease and neurotoxicity of proteins, even if their primary targets are distinct proteins. This thorough analysis explores the complex interactions that exist between the gut microbiota and neurodegenerative illnesses, particularly Parkinson's disease (PD) and prion disorders. The involvement of the gut microbiota, a complex collection of bacteria, archaea, fungi, viruses etc., in various neurological illnesses is becoming increasingly recognized. The gut microbiome influences neuroinflammation, neurotransmitter synthesis, mitochondrial function, and intestinal barrier integrity through the gut-brain axis, which contributes to the development and progression of disease. The review delves into the molecular mechanisms that underlie these relationships, emphasizing the effects of microbial metabolites such as bacterial lipopolysaccharides (LPS), and short-chain fatty acids (SCFAs) in regulating brain functioning. Additionally, it looks at how environmental influences and dietary decisions affect the gut microbiome and whether they could be risk factors for neurodegenerative illnesses. This study concludes by highlighting the critical role that the gut microbiota plays in the development of Parkinson's disease (PD) and prion disease. It also provides a promising direction for future research and possible treatment approaches. People afflicted by these difficult ailments may find hope in new preventive and therapeutic approaches if the role of the gut microbiota in these diseases is better understood.

Snails go on a fast when acetylsalicylic acid comes along with heat stress: A possible effect of HSPs and serotonergic system on the feeding response

A novel food followed by sickness, causes a taste-specific conditioned aversion, known as the 'Garcia effect'. We recently found that both a heat shock stressor (30 °C for 1 h - HS) and the bacterial lipopolysaccharide (LPS) can be used as 'sickness-inducing' stimuli to induce a Garcia effect in the pond snail Lymnaea stagnalis. Additionally, if snails are exposed to acetylsalicylic acid (ASA) present in aspirin tablets before the LPS injection, the formation of the Garcia effect is prevented. Here, we hypothesized that exposing snails to crushed aspirin before the HS (ASA-HS) would prevent the HS-induced 'sickness state' and - therefore -the Garcia effect. Unexpectantly, the ASA-HS procedure induced a generalized and long-lasting feeding suppression. We thus investigate the molecular effects underlying this phenomenon. While the exposure to the HS alone resulted in a significant upregulation of the mRNA levels of the Heat Shock Protein 70 (HSP 70) in snails' central ring ganglia, the ASA-HS procedure induced an even greater upregulation of HSP70, suggesting that the ASA-HS combination causes a severe stress response that inhibits feeding. Additionally, we found that the ASA-HS procedure induced a significant downregulation of the mRNA levels of genes involved with the serotoninergic system which regulates feeding in snails. Finally, the ASA-HS procedure prevented HS-induced upregulation of the mRNA levels of key neuroplasticity genes. Our study indicates that two sickness-inducing stimuli can have different physiological responses even if behavioral outcomes are similar under some learning contexts.

Ghrelin attenuates the inflammatory response induced by experimental endotoxemia in mice

OBJECTIVE

Aim: The aim of this research is to assess the anti-inflammatory effect of ghrelin in mice models of polymicrobial sepsis.

PATIENTS AND METHODS

Materials and Methods: 35 male albino Swiss mice, ages 8-12 weeks, weighing 23-33g, were randomly separated into five groups n = 7; normal group was fed their usual diets until time of sampling, the sham group subjected to Anaesthesia and laparotomy, sepsis group subjected to cecal ligation and puncture, vehicle group was given an equivalent volume of intraperitoneal saline injections immediately after cecal ligation and puncture, and the ghrelin group was treated with 80 μg/kg of ghrelin intraperitoneal injections immediately following cecal ligation and puncture. Twenty hours after cecal ligation and puncture, mice were sacrificed; myocardial tissue and serum samples were collected. Serum IL-1β, NF-κB, and TLR4 levels were measured, and inflammatory response's effects on cardiac tissue were evaluated.

RESULTS

Results: The mean serum IL-1β, NF-κB, and TLR4 levels were markedly elevated in the sepsis and vehicle groups than in the normal and sham groups. The mean serum levels of IL-1β, NF-κB, and TLR4 were considerably lower in the ghrelin-treated group than in the vehicle and sepsis groups. Myocardium tissue of the normal and sham groups showed normal architecture. The sepsis and vehicle groups had a severe myocardial injury. The histological characteristics of ghrelin-treated mice differed slightly from those of the normal and sham groups.

CONCLUSION

Conclusions: Our study concluded that ghrelin exerts anti-inflammatory effects in polymicrobial sepsis, as indicated by a considerable decrease in the IL-1β, NF-κB and TLR4 serum levels.

Transcriptome analysis reveals the impact of NETs activation on airway epithelial cell EMT and inflammation in bronchiolitis obliterans

Bronchiolitis obliterans (BO) is a chronic airway disease that was often indicated by the pathological presentation of narrowed and irreversible airways. However, the molecular mechanisms of BO pathogenesis remain unknown. Although neutrophil extracellular traps (NETs) can contribute to inflammatory disorders, their involvement in BO is unclear. This study aims to identify potential signaling pathways in BO by exploring the correlations between NETs and BO. GSE52761 and GSE137169 datasets were downloaded from gene expression omnibus (GEO) database. A series of bioinformatics analyses such as differential expression analysis, gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and gene set enrichment analysis (GSEA) were performed on GSE52761 and GSE137169 datasets to identify BO potential signaling pathways. Two different types of BO mouse models were constructed to verify NETs involvements in BO. Additional experiments and bioinformatics analysis using human small airway epithelial cells (SAECs) were also performed to further elucidate differential genes enrichment with their respective signaling pathways in BO. Our study identified 115 differentially expressed genes (DEGs) that were found up-regulated in BO. Pathway enrichment analysis revealed that these genes were primarily involved in inflammatory signaling processes. Besides, we found that neutrophil extracellular traps (NETs) were formed and activated during BO. Our western blot analysis on lung tissue from BO mice further confirmed NETs activation in BO, where neutrophil elastase (NE) and myeloperoxidase (MPO) expression were found significantly elevated. Transcriptomic and bioinformatics analysis of NETs treated-SAECs also revealed that NETs-DEGs were primarily associated through inflammatory and epithelial-to-mesenchymal transition (EMT) -related pathways. Our study provides novel clues towards the understanding of BO pathogenesis, in which NETs contribute to BO pathogenesis through the activation of inflammatory and EMT associated pathways. The completion of our study will provide the basis for potential novel therapeutic targets in BO treatment.

IRAK3 Knockout and Wildtype THP-1 Monocytes as Models for Endotoxin Detection Assays and Fusobacterium nucleatum Bacteriophage FNU1 Cytokine Induction

Microbial resistance to antibiotics poses a tremendous challenge. Bacteriophages may provide a useful alternative or adjunct to traditional antibiotics. To be used in therapy, bacteriophages need to be purified from endotoxins and tested for their effects on human immune cells. Interleukin-1 Receptor Associated Kinase-3 (IRAK3) is a negative regulator of inflammation and may play a role in the modulation of immune signalling upon bacteriophage exposure to immune cells. This study aimed to investigate the immune effects of crude and purified bacteriophage FNU1, a bacteriophage that targets the oral pathobiont Fusobacterium nucleatum, on wildtype and IRAK3 knockout THP-1 monocytic cell lines. The IRAK3 knockout cell line was also used to develop a novel endotoxin detection assay. Exposure to crude FNU1 increased the production of pro-inflammatory cytokines (Tumour necrosis factor - alpha (TNF-α) and Interleukin 6 (IL-6)) compared to purified FNU1 in wildtype and IRAK3 knockout THP-1 monocytes. In the IRAK3 knockout THP-1 cells, exposure to crude FNU1 induced a higher immune response than the wildtype monocytes, supporting the suggestion that the inhibitory protein IRAK3 regulates reactions to endotoxins and impurities in bacteriophage preparations. Finally, the novel endotoxin detection assay generated here provides a robust and accurate method for determining endotoxin concentrations.

Dimethyl Fumarate Protects against Lipopolysaccharide- (LPS-) Induced Sepsis through Inhibition of NF-κB Pathway in Mice

Sepsis is one of the most severe complications and causes of mortality in the clinic. It remains a great challenge with no effective treatment for clinicians worldwide. Inhibiting the release of proinflammatory cytokines during sepsis is considered as an important strategy for treating sepsis and improving survival. In the present study, we have observed the effect of dimethyl fumarate (DMF) on lipopolysaccharide- (LPS-) induced sepsis and investigated the possible mechanism. By screening a subset of the Johns Hopkins Drug Library, we identified DMF as a novel inhibitor of nitric oxide synthesis in LPS-stimulated RAW264.7 cells, suggesting that DMF could be a potential drug to treat sepsis. To further characterize the effect of DMF on LPS signaling, TNF-α, MCP-1, G-CMF, and IL-6 expression levels were determined by using cytokine array panels. In addition, an endotoxemia model with C57BL/6 mice was used to assess the in vivo efficacy of DMF on sepsis. The survival rate was assessed, and HE staining was performed to investigate histopathological damage to the organs. DMF was found to increase the survival of septic mice by 50% and attenuate organ damage, consistent with the reduction in IL-10, IL-6, and TNF-α (inflammatory cytokines) in serum. In vitro experiments revealed DMF's inhibitory effect on the phosphorylation of p65, IκB, and IKK, suggesting that the primary inhibitory effects of DMF can be attributed, at least in part, to the inhibition of phosphorylation of IκBα, IKK as well as nuclear factor-κB (NF-κB) upon LPS stimulation. The findings demonstrate that DMF dramatically inhibits NO and proinflammatory cytokine production in response to LPS and improves survival in septic mice, raising the possibility that DMF has the potential to be repurposed as a new treatment of sepsis.

The antimicrobial peptide chensinin-1b alleviates the inflammatory response by targeting the TLR4/NF-κB signaling pathway and inhibits Pseudomonas aeruginosa infection and LPS-mediated sepsis

Excessive inflammatory responses are a major contributor to the high mortality associated with sepsis, a prevalent global complication. Therefore, the potential therapeutic strategy for sepsis involves targeting macrophages and reducing proinflammatory cytokine release. Chensinin-1b, an analog of the natural antimicrobial peptide derived from Rana chensinensis skin secretion, exhibits broad-spectrum antibacterial activity and adopts a random coil conformation in both PBS and membrane solution. By efficiently neutralizing LPS, chensinin-1b holds promise in alleviating LPS-induced inflammatory responses. In this study, we established a mouse septic shock model by exposing mice to multiple-drug-resistant Pseudomonas aeruginosa, as well as an endotoxin-mediated sepsis model induced by LPS. Administering chensinin-1b significantly prolonged the survival of the experimental mice, concurrently mitigating inflammatory responses and reducing organ damage. Additionally, we investigated the anti-inflammatory mechanism of chensinin-1b using a constructed LPS-induced mouse macrophage RAW264.7 inflammatory model. Our findings demonstrated that chensinin-1b effectively mitigated the excessive activation of the TLR4/NF-κB signaling pathway by directly neutralizing extracellular LPS, thus ameliorating the inflammatory response. Moreover, upon blocking the TLR4 signaling pathway, chensinin-1b further reduced the release of proinflammatory cytokines induced by LPS, indicating alternative modes of regulation. Notably, chensinin-1b rapidly entered RAW264.7 cells within 30 min via endocytosis, diffusing into the cytoplasm while retaining its anti-inflammatory properties intracellularly. Although further investigations are warranted to comprehensively elucidate the intracellular anti-inflammatory mechanism of chensinin-1b, our findings substantiate its possession of anti-inflammatory properties both intracellularly and extracellularly. Thus, chensinin-1b emerges as a promising candidate for mitigating excessive inflammatory responses associated with sepsis.

A rare case of Sphingomonas paucimobilis ventriculitis

Introduction

Nosocomial ventriculitis is a severe infection that habitually plagues neurological intensive care units. It is usually associated with external ventricular drains. Unfortunately, classic cerebral spinal fluid parameters are less specific and sensitive compared to community acquired meningitis. This is in part secondary to indolent bacteria commonly infecting external ventricular drains leading to ventriculitis.

Case report

Herein, a rare case of Sphingomonas paucimobilis ventriculitis in an immunocompetent host is reported. The patient had classic symptoms of ventriculitis, but her cerebral spinal fluid parameters were benign and initial cultures were negative. Consequently, treatment was tailored to an assumed respiratory infection only to have recurrence of her symptoms. Repeat analysis of her cerebral spinal fluid was again benign, but her cerebral spinal fluid culture grew S. paucimobilis. Subsequently, the patient was treated with cefepime, which resolved her symptoms. She completed a two-week course and has had no recurrence of her infection.

Conclusions

This case reinforces the need for clinicians to have heightened awareness of this emerging pathogen, its antibiotic resistance patterns, and the unique composition of this bacterium's cell wall which has ramifications on disease presentation.

Evaluating protective effects of botanicals under inflammation and oxidative stress in chicken apical-out enteroids

Botanicals (BOTs) are well known for their anti-inflammatory and antioxidant activities. They have been widely used as feed additives to reduce inflammation and improve intestinal functions in agricultural animals. However, the effects of BOTs on chicken intestinal epithelial functions are not fully understood. The 3D apical-out chicken enteroids recapitulate the intestinal tissue, and allow convenient access to the luminal surface, thus serving as a suitable model for investigating gut functions. The aim of this study was to identify the roles of BOTs in protecting the intestinal epithelium in chicken enteroids under challenging conditions. Apical-out enteroids were isolated from the small intestines of 18 days-old chicken embryos. Lipopolysaccharide (LPS, 10 µg/mL) and menadione (400 µM) challenges were performed in the media with or without BOTs. Paracellular Fluorescein isothiocyanate-dextran 4kD (FD4) permeability, inflammatory cytokine gene expression, and reactive oxygen species (ROS) generation were analyzed post-BOTs and challenges treatments. Statistical analysis was performed using one-way ANOVA and post hoc multiple comparisons among treatments. The results showed that the LPS challenge for 24 h induced a 50% increase in FD4 permeability compared with nontreated control; thymol, thyme essential oil, and phenol-rich extract significantly (P < 0.02) reduced FD4 permeability by 25%, 41%, and 48% respectively, in comparison with LPS treatment. Moreover, the gene expression of inflammatory cytokines was upregulated, tight junction proteins and defensins were downregulated (P < 0.05) after 6 h of LPS treatment, while these BOTs treatments significantly restored the LPS-induced gene expression alterations (P < 0.05). Menadione oxidative challenge for 1 h significantly increased the ROS level compared with unchallenged control. Enteroids treated with thymol and thyme essential oils showed 30% reduced ROS levels, while the phenol-rich extract reduced them by 60%, in comparison with the challenged group (P < 0.0001). These data confirmed the role of BOTs in supporting the barrier function and reducing the disruptive effects of inflammation and oxidation in the chicken intestine.

Preventing bacterial disease in poultry in the post-antibiotic era: a case for innate immunity modulation as an alternative to antibiotic use

The widespread use of antibiotics in the poultry industry has led to the emergence of antibiotic-resistant bacteria, which pose a significant health risk to humans and animals. These public health concerns, which have led to legislation limiting antibiotic use in animals, drive the need to find alternative strategies for controlling and treating bacterial infections. Modulation of the avian innate immune system using immunostimulatory compounds provides a promising solution to enhance poultry immune responses to a broad range of bacterial infections without the risk of generating antibiotic resistance. An array of immunomodulatory compounds have been investigated for their impact on poultry performance and immune responses. However, further research is required to identify compounds capable of controlling bacterial infections without detrimentally affecting bird performance. It is also crucial to determine the safety and effectiveness of these compounds in conjunction with poultry vaccines. This review provides an overview of the various immune modulators known to enhance innate immunity against avian bacterial pathogens in chickens, and describes the mechanisms involved.

Inflammatory hallmarks in 6-OHDA- and LPS-induced Parkinson's disease in rats

Parkinson's disease (PD) is the second most common neurodegenerative disease, affecting more than 1% of aged people. PD, which was previously identified as movement disorder, now is recognized as a multi-factorial systemic disease with important pathogenetic and pathophysiological role of inflammation. Reproducing local and systemic inflammation, which is inherent in PD, in animal models is essential for maximizing the translation of their potential to the clinic, as well as for developing putative anti-inflammatory neuroprotective agents. This study was aimed to compare activation patterns of microglia/macrophage population and systemic inflammation indices in rats with 6-Hydroxydopamine (6-OHDA)- and Lipopolysaccharide (LPS)-induced PD. Metabolic and phenotypic characteristics of microglia/macrophage population were examined by flow cytometry, systemic inflammatory markers were calculated using hematological parameters in 6-OHDA- and LPS-lesioned Wistar rats 29 days after the surgery. Microglia/macrophages from rats in both models exhibited pro-inflammatory metabolic shift. Nevertheless, in LPS-lesioned animals, highly increased proportion of CD80/86+ cells in microglia/macrophage population was registered alongside increased values of systemic inflammatory indices: neutrophil to lymphocyte ratio (NLR), derived neutrophil to lymphocyte ratio (dNLR), platelet to lymphocyte ratio and systemic immune inflammation index (SII). There was significant positive correlation between the count of CD80/86+ cells and systemic inflammatory indices in these animals. Microglia/macrophages from 6-OHDA-lesioned rats were characterized by the increased fraction of CD206+ cells alongside decreased proportion of CD80/86+ cells. No signs of systemic inflammation were observed. Negative correlation between quantitation characteristics of CD80/86+ cells and values of systemic inflammatory indices was registered. Collectively, our data show that LPS-PD model unlike 6-OHDA-PD replicates crosstalk between local and systemic inflammatory responses, which is inherent in PD pathogenesis and pathophysiology.

Fecal and Circulating Biomarkers for the Non-Invasive Assessment of Intestinal Permeability

The study of intestinal permeability is gaining growing interest due to its relevance in the onset and progression of several gastrointestinal and non-gastrointestinal diseases. Though the involvement of impaired intestinal permeability in the pathophysiology of such diseases is recognized, there is currently a need to identify non-invasive biomarkers or tools that are able to accurately detect alterations in intestinal barrier integrity. On the one hand, promising results have been reported for novel in vivo methods based on paracellular probes, i.e., methods that can directly assess paracellular permeability and, on the other hand, on fecal and circulating biomarkers able to indirectly assess epithelial barrier integrity and functionality. In this review, we aimed to summarize the current knowledge on the intestinal barrier and epithelial transport pathways and to provide an overview of the methods already available or currently under investigation for the measurement of intestinal permeability.

MNQ derivative D21 protects against LPS-induced inflammatory damage in bovine ovarian follicular GCs in vitro via the steroid biosynthesis signaling pathway

Bacterial infections of the reproductive system of dairy cows lead to inflammation, and lipopolysaccharide (LPS) of the cell wall of Gram-negative bacteria is the main pathogenic component of inflammation. LPS inhibits follicular growth and development and alters the expression of follicular granulosa cells (GCs) genes in the ovary, leading to their functional disorders. Naphthoquinones have anti-inflammatory effects. In this experiment, 2-methoxy-1,4-naphthoquinone (MNQ), an extract of Impatiens balsamina L, and its derivative D₂₁ were used to eliminate the inflammatory response of GCs exposed to LPS in vitro and to restore functional disorders in GCs. The anti-inflammatory effects of the two compounds were compared and their mechanism of action was investigated. The cytotoxicity of MNQ and its derivative D₂₁ on follicular GCs was determined by MTT method. The relative expression of inflammatory factors and steroid synthesis-related genes were determined by qRT-PCR. The protective effects of MNQ and D₂₁ on cellular inflammatory damage were observed by TEM. ELISA were performed to detect the levels of estradiol (E₂) and progesterone (P₄) in the culture supernatant. The expression of differential genes was analyzed by RNA-seq, and GO and KEGG enrichment analysis of differential genes were performed to investigate the mechanism of anti-inflammatory effect of D₂₁. The results showed that the maximum no-cytotoxic concentrations of MNQ and D₂₁ acting on GCs for 12 h were 4 μM and 64 μM, respectively. LPS concentration of 10 μg/mL had little effect on the survival of follicular GCs, but the relative expressions of IL-6, IL-1β and TNF-α were significantly higher (P < 0.05). The results of qRT-PCR, ELISA and TEM observations showed that the anti-inflammatory effect of D₂₁ was stronger than that of MNQ. RNA-seq analysis revealed a total of 341 differential genes between the LPS vs CK group (Control group) and the D₂₁+L vs LPS group, which were mainly enriched in signaling pathways such as steroid biosynthesis. Nine genes in this signaling pathway were analyzed, and the RNA-seq and qRT-PCR results were found to be basically consistent. In this study, we confirmed that derivative D₂₁ has stronger in vitro anti-inflammatory effects and better efficacy in protecting bovine follicular GCs from inflammatory damage than MNQ and acts through the steroid biosynthesis signaling pathway.

Novel taste, sickness, and memory: Lipopolysaccharide to induce a Garcia-like effect in inbred and wild strains of Lymnaea stagnalis

Food is not only necessary for our survival but also elicits pleasure. However, when a novel food is followed sometime later by nausea or sickness animals form a long-lasting association to avoid that food. This phenomenon is called the 'Garcia effect'. We hypothesized that lipopolysaccharide (LPS) could be used as the sickness-inducing stimulus to produce a Garcia-like effect in inbred and wild populations of Lymnaea stagnalis. We first demonstrated that the injection of 25 μg (6.25 µg/mL) of Escherichia coli-derived LPS serotype O127:B8 did not by itself alter snails' feeding behavior. Then we showed that the presentation of a novel appetitive stimulus (i.e., carrot slurry) and LPS resulted in a taste-specific and long-lasting feeding suppression (i.e., the Garcia-like effect). We also found strain-specific variations in the duration of the long-term memory (LTM). That is, while the LTM for the Garcia-like effect in W-strain snails persisted for 24h, LTM persisted for 48h in freshly collected Margo snails and their F1 offspring. Finally, we demonstrated that the exposure to a non-steroidal anti-inflammatory drug, aspirin (acetylsalicylic acid) before the LPS injection prevented both the LPS-induced sickness state and the Garcia-like effect from occurring. The results of this study may pave the way for new research that aims at (1) uncovering the conserved molecular mechanisms underlying the Garcia-like effect, (2) understanding how cognitive traits vary within and between species, and (3) creating a holistic picture of the complex dialogue between the immune and central nervous systems.

Neutrophil-inspired photothermo-responsive drug delivery system for targeted treatment of bacterial infection and endotoxins neutralization

BACKGROUND

P. aeruginosa, a highly virulent Gram-negative bacterium, can cause severe nosocomial infections, and it has developed resistance against most antibiotics. New therapeutic strategies are urgently needed to treat such bacterial infection and reduce its toxicity caused by endotoxin (lipopolysaccharide, LPS). Neutrophils have been proven to be able to target inflammation site and neutrophil membrane receptors such as Toll-like receptor-4 (TLR4) and CD14, and exhibit specific affinity to LPS. However, antibacterial delivery system based on the unique properties of neutrophils has not been reported.

METHODS

A neutrophil-inspired antibacterial delivery system for targeted photothermal treatment, stimuli-responsive antibiotic release and endotoxin neutralization is reported in this study. Specifically, the photothermal reagent indocyanine green (ICG) and antibiotic rifampicin (RIF) are co-loaded into poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NP-ICG/RIF), followed by coating with neutrophil membrane to obtain antibacterial delivery system (NM-NP-ICG/RIF). The inflammation targeting properties, synergistic antibacterial activity of photothermal therapy and antibiotic treatment, and endotoxin neutralization have been studied in vitro. A P. aeruginosa-induced murine skin abscess infection model has been used to evaluate the therapeutic efficacy of the NM-NP-ICG/RIF.

RESULTS

Once irradiated by near-infrared lasers, the heat generated by NP-ICG/RIF triggers the release of RIF and ICG, resulting in a synergistic chemo-photothermal antibacterial effect against P. aeruginosa (~ 99.99% killing efficiency in 5 min). After coating with neutrophil-like cell membrane vesicles (NMVs), the nanoparticles (NM-NP-ICG/RIF) specifically bind to inflammatory vascular endothelial cells in infectious site, endowing the nanoparticles with an infection microenvironment targeting function to enhance retention time. Importantly, it is discovered for the first time that NMVs-coated nanoparticles are able to neutralize endotoxins. The P. aeruginosa murine skin abscess infection model further demonstrates the in vivo therapeutic efficacy of NM-NP-ICG/RIF.

CONCLUSION

The neutrophil-inspired antibacterial delivery system (NM-NP-ICG/RIF) is capable of targeting infection microenvironment, neutralizing endotoxin, and eradicating bacteria through a synergistic effect of photothermal therapy and antibiotic treatment. This drug delivery system made from FDA-approved compounds provides a promising approach to fighting against hard-to-treat bacterial infections.

Escherichia coli enhances Th17/Treg imbalance via TLR4/NF-κB signaling pathway in oral lichen planus

Oral lichen planus (OLP) is a T-cell-mediated immunoinflammatory disease. Several studies have proposed that Escherichia coli (E. coli) may participate in the progress of OLP. In this study, we examined the functional role of E. coli and its supernatant via toll-like receptor 4 (TLR4)/nuclear factor-kappab (NF-κB) signaling pathway in regulating T helper (Th) 17/ regulatory T (Treg) balance and related cytokines and chemokines profile in OLP immune microenvironment. We discovered that E. coli and supernatant could activate the TLR4/NF-κB signaling pathway in human oral keratinocytes (HOKs) and OLP-derived T cells and increase the expression of interleukin (IL)-6, IL-17, C-C motif chemokine ligand (CCL) 17 and CCL20, thereby increasing the expression of retinoic acid-related orphan receptor (RoRγt) and the proportion of Th17 cells. Furthermore, the co-culture experiment revealed that HOKs treated with E. coli and supernatant increased T cell proliferation and migration, which promoted HOKs apoptosis. TLR4 inhibitor (TAK-242) successfully reversed the effect of E. coli and its supernatant. Consequently, E. coli and supernatant activated the TLR4/NF-κB signaling pathway in HOKs and OLP-derived T cells, leading to increased cytokines and chemokines expression and Th17/Treg imbalance in OLP.

LPS-aggregating proteins GBP1 and GBP2 are each sufficient to enhance caspase-4 activation both in cellulo and in vitro

The gamma-interferon (IFNγ)-inducible guanylate-binding proteins (GBPs) promote host defense against gram-negative cytosolic bacteria in part through the induction of an inflammatory cell death pathway called pyroptosis. To activate pyroptosis, GBPs facilitate sensing of the gram-negative bacterial outer membrane component lipopolysaccharide (LPS) by the noncanonical caspase-4 inflammasome. There are seven human GBP paralogs, and it is unclear how each GBP contributes to LPS sensing and pyroptosis induction. GBP1 forms a multimeric microcapsule on the surface of cytosolic bacteria through direct interactions with LPS. The GBP1 microcapsule recruits caspase-4 to bacteria, a process deemed essential for caspase-4 activation. In contrast to GBP1, closely related paralog GBP2 is unable to bind bacteria on its own but requires GBP1 for direct bacterial binding. Unexpectedly, we find that GBP2 overexpression can restore gram-negative-induced pyroptosis in GBP1KO cells, without GBP2 binding to the bacterial surface. A mutant of GBP1 that lacks the triple arginine motif required for microcapsule formation also rescues pyroptosis in GBP1KO cells, showing that binding to bacteria is dispensable for GBPs to promote pyroptosis. Instead, we find that GBP2, like GBP1, directly binds and aggregates "free" LPS through protein polymerization. We demonstrate that supplementation of either recombinant polymerized GBP1 or GBP2 to an in vitro reaction is sufficient to enhance LPS-induced caspase-4 activation. This provides a revised mechanistic framework for noncanonical inflammasome activation where GBP1 or GBP2 assembles cytosol-contaminating LPS into a protein-LPS interface for caspase-4 activation as part of a coordinated host response to gram-negative bacterial infections.

Dynamic changes in gut microbiota during pregnancy among Chinese women and influencing factors: A prospective cohort study

Gut microbiota (GM) dynamics during pregnancy vary among different populations and are affected by many factors, such as living environments and diet. This study aims to observe and evaluate the changes in the structure and function of the GM from the first to the third trimester of pregnancy in Chinese women, and to explore the main factors affecting the changes in intestinal microecology. Fifty-five Chinese pregnant women were recruited for this study and their fecal samples were collected during the first (P1), second (P2), and third trimesters (P3) of pregnancy. We exploited metagenomic sequencing to compare the composition and function of the GM in different pregnancy periods. Bioinformatic analysis revealed that there were differences in the composition of the GM among P1, P2, and P3, as indicated by the increase in α-diversity and β-diversity of the GM and the differences in the relative abundances of distinct bacterial phyla. Gestational diabetes mellitus (GDM) was the main factor (P &lt; 0.05) that affected the changes in GM at various stages of pregnancy. There were also disparities in the structure of the GM between the GDM group and non-GDM group in the P1, P2, and P3. The GDM group exhibited increased abundances in Ruminococcus_gnavus, Akkermansia_muciniphila, Alistipes_shahii, Blautia_obeum, and Roseburia_intestinalis; while, the abundances of Bacteroides coprocola, Bacteroides plebeius, Erysipelatoclostridium ramosum, and Prevotella copri were increased in the non-GDM group. Three of the four species enriched in the non-GDM group manifestied significantly negative correlations with the insulin-signaling pathway and lipopolysaccharide biosynthesis (r ≤ −0.3, adjusted P &lt; 0.05). In the GDM group, Bacteroides vulgatus and Ruminococcus gnavus were significantly and positively correlated with insulin signaling pathway and lipopolysaccharide biosynthesis (r ≤ −0.3, adjusted P &lt; 0.05) among the species enriched from early pregnancy. Virtually all of the species enriched in P2 and P3 were positively correlated with steroid hormone biosynthesis. These results suggest a potential role for the GM in the development of GDM, enabling the potential prevention of GDM by targeting the GM.

HIV/Mtb Co-Infection: From the Amplification of Disease Pathogenesis to an “Emerging Syndemic”

Human immunodeficiency virus (HIV) and Mycobacterium tuberculosis (Mtb) are pathogens responsible for millions of new infections each year; together, they cause high morbidity and mortality worldwide. In addition, late-stage HIV infection increases the risk of developing tuberculosis (TB) by a factor of 20 in latently infected people, and even patients with controlled HIV infection on antiretroviral therapy (ART) have a fourfold increased risk of developing TB. Conversely, Mtb infection exacerbates HIV pathogenesis and increases the rate of AIDS progression. In this review, we discuss this reciprocal amplification of HIV/Mtb coinfection and how they influence each other’s pathogenesis. Elucidating the infectious cofactors that impact on pathogenesis may open doors for the design of new potential therapeutic strategies to control disease progression, especially in contexts where vaccines or the sterile clearance of pathogens are not effectively available.

Microbiome-gut-brain dysfunction in prodromal and symptomatic Lewy body diseases

Lewy body diseases, such as Parkinson's disease and dementia with Lewy bodies, vary in their clinical phenotype but exhibit the same defining pathological feature, α-synuclein aggregation. Microbiome-gut-brain dysfunction may play a role in the initiation or progression of disease processes, though there are multiple potential mechanisms. We discuss the need to evaluate gastrointestinal mechanisms of pathogenesis across Lewy body diseases, as disease mechanisms likely span across diagnostic categories and a 'body first' clinical syndrome may better account for the heterogeneity of clinical presentations across the disorders. We discuss two primary hypotheses that suggest that either α-synuclein aggregation occurs in the gut and spreads in a prion-like fashion to the brain or systemic inflammatory processes driven by gastrointestinal dysfunction contribute to the pathophysiology of Lewy body diseases. Both of these hypotheses posit that dysbiosis and intestinal permeability are key mechanisms and potential treatment targets. Ultimately, this work can identify early interventions targeting initial disease pathogenic processes before the development of overt motor and cognitive symptoms.

Genes mcr improve the intestinal fitness of pathogenic E. coli and balance their lifestyle to commensalism

BACKGROUND

The plasmid-mediated resistance gene mcr-1 confers colistin resistance in Escherichia coli and paves the way for the evolution to pan-drug resistance. We investigated the impact of mcr-1 in gut colonization in the absence of antibiotics using isogenic E. coli strains transformed with a plasmid encoding or devoid of mcr-1.

RESULTS

In gnotobiotic and conventional mice, mcr-1 significantly enhanced intestinal anchoring of E. coli but impaired their lethal effect. This improvement of intestinal fitness was associated with a downregulation of intestinal inflammatory markers and the preservation of intestinal microbiota composition. The mcr-1 gene mediated a cross-resistance to antimicrobial peptides secreted by the microbiota and intestinal epithelial cells (IECs), enhanced E. coli adhesion to IECs, and decreased the proinflammatory activity of both E. coli and its lipopolysaccharides.

CONCLUSION

Overall, mcr-1 changed multiple facets of bacterial behaviour and appeared as a factor enhancing commensal lifestyle and persistence in the gut even in the absence of antibiotics. Video Abstract.

A signature of immune-related genes correlating with clinical prognosis and immune microenvironment in sepsis

BACKGROUND

Immune-related genes (IRGs) remain poorly understood in their function in the onset and progression of sepsis.

METHODS

GSE65682 was obtained from the Gene Expression Omnibus database. The IRGs associated with survival were screened for subsequent modeling using univariate Cox regression analysis and least absolute shrinkage and selection operator in the training cohort. Then, we assessed the reliability of the 7 IRGs signature's independent predictive value in the training and validation cohorts following the creation of a signature applying multivariable Cox regression analysis. After that, we utilized the E-MTAB-4451 external dataset in order to do an independent validation of the prognostic signature. Finally, the CIBERSORT algorithm and single-sample gene set enrichment analysis was utilized to investigate and characterize the properties of the immune microenvironment.

RESULTS

Based on 7 IRGs signature, patients could be separated into low-risk and high-risk groups. Patients in the low-risk group had a remarkably increased 28-day survival compared to those in the high-risk group (P < 0.001). In multivariable Cox regression analyses, the risk score calculated by this signature was an independent predictor of 28-day survival (P < 0.001). The signature's predictive ability was confirmed by receiver operating characteristic curve analysis with the area under the curve reaching 0.876 (95% confidence interval 0.793-0.946). Moreover, both the validation set and the external dataset demonstrated that the signature had strong clinical prediction performance. In addition, patients in the high-risk group were characterized by a decreased neutrophil count and by reduced inflammation-promoting function.

CONCLUSION

We developed a 7 IRGs signature as a novel prognostic marker for predicting sepsis patients' 28-day survival, indicating possibilities for individualized reasonable resource distribution of intensive care unit.

Effects of Magnetic Nanoparticles on the Functional Activity of Human Monocytes and Dendritic Cells

The use of nanoparticles in medicine is sometimes hampered by their potential to activate immune cells, eliciting inflammation or allergy. We investigated whether magnetic nanoparticles (MNPs) or biomimetic magnetic nanoparticles (BMNPs) affect relevant activities of human monocytes. We found that the nanoparticles neither elicited the production of pro-inflammatory mediators IL-6 and TNFα by resting monocytes (when BMNP dose < 300 μg/mL) nor enhanced their secretion induced by R848, a molecule engaging virus-recognizing receptors, or bacterial lipopolysaccharide (LPS). MNPs and BMNPs neither induced the generation of reactive oxygen species (ROS), nor affected the ROS production elicited by the NADPH oxidase activator phorbol myristate acetate (PMA) or the fungal derivative β-glucan. BMNPs, but not MNPs, caused an up-regulation of the maturation markers CD80, CD83, and CD86 in immature monocyte-derived dendritic cells (DCs), whereas both nanoparticles did not affect the LPS-induced expression of these markers. Moreover, the nanoparticles were greedily ingested by monocytes and DCs without altering their viability. Therefore, these nanoparticles are candidates for medical applications because they do not activate pro-inflammatory activities of monocytes. Furthermore, their ability to stimulate DC maturation could be used for the design of vaccines. Moreover, harmlessly engulfed nanoparticles could be vehicles to carry molecules inside the immune cells to regulate the immune response.

Kinin B1 Receptor Mediates Bidirectional Interaction between Neuroinflammation and Oxidative Stress

Hypertension is associated with increased expression of kinin B1 receptors (B1R) and increased levels of pro-inflammatory cytokines within the neurons. We previously reported that angiotensin II (Ang II) upregulates B1R expression and can induce neuroinflammation and oxidative stress in primary hypothalamic neurons. However, the order in which B1R activation, neuroinflammation, and oxidative stress occur has not yet been studied. Using primary hypothalamic neurons from neonatal mice, we show that tumor necrosis factor (TNF), lipopolysaccharides (LPS), and hydrogen peroxide (H₂O₂) can upregulate B1R expression and increase oxidative stress. Furthermore, our study shows that B1R blockade with R715, a specific B1R antagonist, can attenuate these effects. To further confirm our findings, we used a deoxycorticosterone acetate (DOCA)-salt model of hypertension to show that oxidative stress is upregulated in the hypothalamic paraventricular nucleus (PVN) of the brain. Together, these data provide novel evidence that relationship between oxidative stress, neuroinflammation, and B1R upregulation in the brain is bidirectional, and that B1R antagonism may have beneficial effects on neuroinflammation and oxidative stress in various disease pathologies.

Dual roles of anesthetics in postoperative cognitive dysfunction: Regulation of microglial activation through inflammatory signaling pathways

Postoperative cognitive dysfunction (POCD) is a prevalent clinical entity following surgery and is characterized by declined neurocognitive function. Neuroinflammation mediated by microglia is the essential mechanism of POCD. Anesthetics are thought to be a major contributor to the development of POCD, as they promote microglial activation and induce neuroinflammation. However, this claim remains controversial. Anesthetics can exert both anti- and pro-inflammatory effects by modulating microglial activation, suggesting that anesthetics may play dual roles in the pathogenesis of POCD. Here, we review the mechanisms by which the commonly used anesthetics regulate microglial activation via inflammatory signaling pathways, showing both anti- and pro-inflammatory properties of anesthetics, and indicating how perioperative administration of anesthetics might either relieve or worsen POCD development. The potential for anesthetics to enhance cognitive performance based on their anti-inflammatory properties is further discussed, emphasizing that the beneficial effects of anesthetics vary depending on dose, exposure time, and patients' characteristics. To minimize the incidence of POCD, we recommend considering these factors to select appropriate anesthetics.

Dietary methionine restriction alleviates oxidative stress and inflammatory responses in lipopolysaccharide-challenged broilers at early age

In this study, we investigated the effect of dietary methionine restriction (MR) on the antioxidant function and inflammatory responses in lipopolysaccharide (LPS)-challenged broilers reared at high stocking density. A total of 504 one-day-old male Arbor Acre broiler chickens were randomly divided into four treatments: 1) CON group, broilers fed a basal diet; 2) LPS group, LPS-challenged broilers fed a basal diet; 3) MR1 group, LPS-challenged broilers fed a methionine-restricted diet (0.3% methionine); and 4) MR2 group, LPS-challenged broilers fed a methionine-restricted diet (0.4% methionine). LPS-challenged broilers were intraperitoneally injected with 1 mg/kg body weight (BW) of LPS at 17, 19, and 21 days of age, whereas the CON group was injected with sterile saline. The results showed that: LPS significantly increased the liver histopathological score (p < 0.05); LPS significantly decreased the serum total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activity at 3 h after injection (p < 0.05); the LPS group had a higher content of Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF)-α, but a lower content of IL-10 than the CON group in serum (p < 0.05). Compared with the LPS group, the MR1 diet increased catalase (CAT), SOD, and T-AOC, and the MR2 diet increased SOD and T-AOC at 3 h after injection in serum (p < 0.05). Only MR2 group displayed a significantly decreased liver histopathological score (p < 0.05) at 3 h, while MR1 and MR2 groups did so at 8 h. Both MR diets significantly decreased serum LPS, CORT, IL-1β, IL-6, and TNF-α contents, but increased IL-10 content (p < 0.05). Moreover, the MR1 group displayed significantly increased expression of nuclear factor erythroid 2-related factor 2 (Nrf2), CAT, and GSH-Px at 3 h; the MR2 group had a higher expression of Kelch-like ECH-associated protein 1 (Keap1), SOD, and GSH-Px at 8 h (p < 0.05). In summary, MR can improve antioxidant capacity, immunological stress, and liver health in LPS-challenged broilers. The MR1 and MR2 groups experienced similar effects on relieving stress; however, MR1 alleviated oxidative stress more rapidly. It is suggested that precise regulation of methionine levels in poultry with stress may improve the immunity of broilers, reduce feed production costs, and increase production efficiency in the poultry industry.

Characterization and bioactivity analysis of a heteropolysaccharide purified from Paenibacillus edaphicus strain UJ1

Many polysaccharides produced by Paenibacillus spp. have attractive properties, such as rheological modification and immunomodulation. However, properties of P. edaphicus polysaccharides are not understood sufficiently. Here, the polysaccharide (PUM) was obtained from P. edaphicus strain UJ1 by batch fermentation, and the chemical characteristics, rheological and anti-inflammatory properties of PUM and its sulfate derivative (PUM-S) were investigated. The results indicated that PUM was a typical shear-thinning biopolymer with an estimated weight average molecular weight of 2.45 × 10⁷ Da. PUM molecule consisted of D-Man, D-GlcA, D-Glc, D-Gal, and L-Fuc with the molar ratio of 3.00:1.07:3.21:0.81:0.76. It had the backbone → 3)-β-D-Man-(1 → 3)-β-D-Glc-(1 → 3)-β-D-Man-(1 → 3)β-D-Glc-(1 → 4)-β-D-GlcA-(1 → 3)-β-D-Man-(1 → and two side chains, namely, pyruvoyl-Glc-(1→ and β-L-Fuc-(1 → 3)-β-D-Gal-(1→. Moreover, PUM-S was prepared by SO₃-pyridine method and had the weight average molecular weight of 1.42 × 10⁵ Da. The bioactivity of PUM and PUM-S was analyzed in vitro in RAW 264.7 cells. The results indicated that both PUM and PUM-S facilitated cell proliferation at 50-500 μg/mL. Besides, PUM-S showed potential anti-inflammatory effect in the LPS-induced cells. According to transcription and molecular dynamics analyses, PUM-S expressed its activity probably by interacting with the Toll-like receptor 4. In general, P. edaphicus produced a polysaccharide with new chemical structure and promising rheological and bioactive properties.

Multi-Omics Integration to Reveal the Mechanism of Sericin Inhibiting LPS-Induced Inflammation

Sericin is a natural protein with high application potential, but the research on its efficacy is very limited. In this study, the anti-inflammatory mechanism of sericin protein was investigated. Firstly, the protein composition of sericin extracts was determined by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). This was then combined with Enzyme-linked Immunosorbent Assay (ELISA) and Quantitative Real-time PCR (qRT-PCR), and it was confirmed that the anti-inflammation ability of sericin was positively correlated with the purity of sericin 1 protein. Finally, RNA-seq was performed to quantify the inhibitory capacity of sericin sample SS2 in LPS-stimulated macrophages. The gene functional annotation showed that SS2 suppressed almost all PRRs signaling pathways activated by lipopolysaccharides (LPS), such as the Toll-like receptors (TLRs) and NOD-like receptors (NLRs) signaling pathways. The expression level of adaptor gene MyD88 and receptor gene NOD1 was significantly down-regulated after SS2 treatment. SS2 also reduced the phosphorylation levels of NF-κB P65, P38, and JNK, thereby reducing the expressions of IL-1β, IL-6, INOS, and other inflammatory cytokines. It was confirmed that sericin inhibited LPS-induced inflammation through MyD88/NF-κB pathway. This finding provides necessary theoretical support for sericin development and application.

TLR4/CD14/MD2 Revealed as the Limited Toll-like Receptor Complex for Chlamydia trachomatis-Induced NF-κB Signaling

Chlamydia trachomatis (Ct) is the most common cause of genital tract infections as well as preventable blindness worldwide. Pattern recognition receptors such as toll-like receptors (TLRs) represent the initial step in recognizing pathogenic microorganisms and are crucial for the initiation of an appropriate immune response. However, our understanding of TLR-signaling in Chlamydia-infected immune cells is incomplete. For a better comprehension of pathological inflammatory responses, robust models for interrogating TLR-signaling upon chlamydial infections are needed. To analyze the TLR response, we developed and utilized a highly sensitive and selective fluorescent transcriptional cellular reporter system to measure the activity of the transcription factor NF-κB. Upon incubation of the reporter cells with different preparations of Ct, we were able to pinpoint which components of TLRs are involved in the recognition of Ct. We identified CD14 associated with unique characteristics of different serovars as the crucial factor of the TLR4/CD14/MD2 complex for Ct-mediated activation of the NF-κB pathway. Furthermore, we found the TLR4/CD14/MD2 complex to be decisive for the uptake of Ct-derived lipopolysaccharides but not for infection and replication of Ct. Imaging flow cytometry provided information about inclusion formation in myeloid- as well as lymphocytic cells and was highest for Ct L2 with at least 25% of inclusion forming cells. Ct E inclusion formation was eminent in Jurkat cells without CD14 expression (11.1%). Thus, our model enables to determine Ct uptake and signal induction by pinpointing individual components of the recognition and signaling pathways to better understand the immune response towards infectious pathogens.

Aspirin reverts lipopolysaccharide-induced learning and memory impairment: first evidence from an invertebrate model system

By employing a reductionistic (but not simplistic) approach using an established invertebrate model system, the pond snail Lymnaea stagnalis, we investigated whether (1) lipopolysaccharide (LPS)-induced inflammation would cause a sickness state and impair cognitive function, and-if so-(2) would aspirin (acetylsalicylic acid-ASA) restore the impaired cognition. To test our hypotheses, we first determined if the injection of 25 mg (6.25 μg/mL) of Escherichia coli-derived LPS serotype O127:B8 altered homeostatic behavior, aerial respiration, and then determined if LPS altered memory formation when this behavior was operantly conditioned. Next, we determined if ASA altered the LPS-induced changes in both aerial respiration and cognitive functions. LPS induced a sickness state that increased aerial respiration and altered the ability of snails to form or recall long-term memory. ASA reverted the LPS-induced sickness state and thus allowed long-term memory both to be formed and recalled. We confirmed our hypotheses and provided the first evidence in an invertebrate model system that an injection of LPS results in a sickness state that obstructs learning and memory, and this impairment can be prevented by a non-steroidal anti-inflammatory.

The Neuroprotective and Antioxidant Effects of Nanocurcumin Oral Suspension against Lipopolysaccharide-Induced Cortical Neurotoxicity in Rats

Lipopolysaccharide (LPS) proved to be an important tool, not only in the induction of neuroinflammatory models, but also in demonstrating the behavioral and cognitive consequences of endotoxemia. Curcumin, in its native form, has proven to be a worthy candidate for further development as it protects the dopaminergic neurons against LPS-induced neurotoxicity. However, it remains hindered by its poor bioavailability. In this study we aim to explore the possible molecular mechanism of LPS-induced neurotoxicity and the possible protective effects of orally supplemented nanocurcumin. Thirty-six adult male Wistar rats weighing 170-175 g were divided into six groups and treated with single I.P. (intra-peritoneal) dose of LPS (sigma and extracted; separately) (5 mg/kg BW) plus daily oral nanocurcumin (15 mg/kg BW). The rats were followed for 7 days after the LPS injection and nanocurcumin supplementations daily via oral gavage. After scarification, the levels of neurotransmitters, antioxidants, and amyloidogenesis markers were assessed in brain tissues. Nanocurcumin showed adequate antioxidant and neuroprotective effects, rescuing the rats which had been injected intraperitoneally with LPS endotoxin.

Maternal nucleotide supplementation improves the intestinal morphology and immune function in lipopolysaccharide-challenged newborn piglets

This study aimed to evaluate the effects of maternal nucleotide (NT) supplementation on intestinal morphology and immune function in lipopolysaccharide-challenged newborn piglets. At 85 d gestation, 12 sows were selected and assigned to two groups: the CON group (basal diet, n = 6) and the NT group (basal diet with 1 g/kg NT mixture, n = 6). After parturition, newborn piglets were collected without suckling. Piglets from the CON group were intraperitoneally injected with sterile saline or lipopolysaccharide (LPS, 10 mg/kg body weight), and divided into the C-CON (n = 6) and C-LPS groups (n = 6). Piglets from the NT group received the same treatment and were divided into the N-CON (n = 6) and N-LPS groups (n = 6). The blood and small intestinal samples of piglets were collected 1 h after injection. The results showed that: (1) maternal NT supplementation increased the concentrations of serum complement C3 and C4 (P < 0.05), and suppressed the increase in serum hypersensitive C-reactive protein in LPS-challenged newborn piglets (P < 0.05); (2) maternal NT supplementation increased the villus height and the ratio of villus height to crypt depth in the duodenum of newborn piglets (P < 0.05) and inhibited the LPS-induced decrease in the villus height in the jejunum and ileum (P < 0.05). (3) The LPS-induced increased levels of interleukin-6 in the jejunum and tumor necrosis factor-α in the ileum of newborn piglets were suppressed by maternal NT supplementation (P < 0.05). (4) In the jejunum of newborn piglets, maternal NT supplementation inhibited the LPS-induced increase in toll-like receptor 4 (TLR4) mRNA and protein expression (P < 0.05) and the decrease of nuclear factor-κB inhibitor α (IκBα) protein expression (P < 0.05). In the ileum, piglets had a lower nuclear factor-κB (NFκB) mRNA expression in the NT groups than the CON groups (P < 0.05), and maternal NT supplementation suppressed the decrease of IκBα mRNA in LPS-treated piglets (P < 0.05). In conclusion, maternal NT supplementation could promote the intestinal development and immune function of newborn piglets, and may improve LPS-induced intestinal inflammatory responses via the TLR4/IκBα/NFκB pathway.

The potential impact of a probiotic: Akkermansia muciniphila in the regulation of blood pressure—the current facts and evidence

Akkermansia muciniphila (A. muciniphila) is present in the human gut microbiota from infancy and gradually increases in adulthood. The potential impact of the abundance of A. muciniphila has been studied in major cardiovascular diseases including elevated blood pressure or hypertension (HTN). HTN is a major factor in premature death worldwide, and approximately 1.28 billion adults aged 30–79 years have hypertension. A. muciniphila is being considered a next-generation probiotic and though numerous studies had highlighted the positive role of A. muciniphila in lowering/controlling the HTN, however, few studies had highlighted the negative impact of increased abundance of A. muciniphila in the management of HTN. Thus, in the review, we aimed to discuss the current facts, evidence, and controversy about the role of A. muciniphila in the pathophysiology of HTN and its potential effect on HTN management/regulation, which could be beneficial in identifying the drug target for the management of HTN.