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-1ß, NF-κB, and TLR4 levels were measured, and inflammatory response's effects on cardiac tissue were evaluated. RESULTS: Results: The mean serum IL-1ß, 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-1ß, 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-1ß, NF-κB and TLR4 serum levels.

Obesity and polycystic ovary syndrome influence on intestinal permeability at fasting, and modify the effect of diverse macronutrients on the gut barrier.

Women with the extremely prevalent polycystic ovary syndromegather multiple cardiovascular risk factors and chronic subclinical inflammation. Interactions between diet, adiposity, and gut microbiota modulate intestinal permeabilityand bacterial product translocation, and may contribute to the chronic inflammation process associated with the polycystic ovary syndrome. In the present study, we aimed to address the effects of obesity, functional hyperandrogenism, and diverse oral macronutrients on intestinal permeabilityby measuring circulating markers of gut barrier dysfunction and endotoxemia. Participants included 17 non-hyperandrogenic control women, 17 women with polycystic ovary syndrome, and 19 men that were submitted to glucose, lipid, and protein oral loads. Lipopolysaccharide-binding protein, plasma soluble CD14, succinate, zonulin family peptide, and glucagon-like peptide-2 were determined at fasting and after oral challenges. Macronutrient challenges induced diverse changes on circulating intestinal permeabilitybiomarkers in the acute postprancial period, with lipids and proteins showing the most unfavorable and favorable effects, respectively. Particularly, lipopolysaccharide-binding protein, zonulin family peptide, and glucagon-like peptide-2 responses were deregulated by the presence of obesity after glucose and lipid challenges. Obese subjects showed higher fasting intestinal permeabilitybiomarkers levels than non-obese individuals, except for plasma soluble CD14. The polycystic ovary syndromeexacerbated the effect of obesity further increasing fasting glucagon-like peptide-2, lipopolysaccharide-binding protein, and succinate concentrations. We observed specific interactions of the polycystic ovary syndromewith obesity in the postprandial response of succinate, zonulin family peptide, and glucagon-like peptide-2. In summary, obesity and polycystic ovary syndromemodify the effect of diverse macronutrients on the gut barrier, and alsoinfluence intestinal permeabilityat fasting,contributing to the morbidity of functional hyperandrogenism by inducing endotoxemia and subclinical chronic inflammation.

Mogroside Alleviates Diabetes Mellitus and Modulates Intestinal Microflora in Type 2 Diabetic Mice.

Mogroside, the main component of Siraitia grosvenorii (Swingle) C. Jeffrey (Cucurbitaceae) is a natural product with hypoglycemic and intestinal microbiota regulating properties. However, whether the alteration of intestinal microbiota is associated with the antidiabetic effect of mogroside remains poorly understood. This study investigated the mechanism underlying the hypoglycemic effect of mogroside in regulating intestinal flora and attenuating metabolic endotoxemia. Kunming mice with type 2 diabetes mellitus (T2DM) induced by high-fat diet and intraperitoneal injection of streptozotocin were randomly divided into model, pioglitazone (2.57 mg/kg) and mogroside (200, 100, and 50 mg/kg) groups. After 28 d of administration, molecular changes related to glucose metabolism and metabolic endotoxemia in mice were evaluated. The levels of insulin receptor substrate-1 (IRS-1), cluster of differentiation 14 (CD14) and toll-like receptor 4 (TLR4) mRNAs were measured, and the composition of intestinal microflora was determined by 16s ribosomal DNA (rDNA) sequencing. The results showed that mogroside treatment significantly improved hepatic glucose metabolism in T2DM mice. More importantly, mogroside treatment considerably reduced plasma endotoxin (inhibition rate 65.93%, high-dose group) and inflammatory factor levels, with a concomitant decrease in CD14 and TLR4 mRNA levels. Moreover, mogroside treatment reduced the relative abundance of Firmicutes and Proteobacteria (the inhibition rate of Proteobacteria was 85.17% in the low-dose group) and increased the relative abundance of Bacteroidetes (growth rate up to 40.57%, high-dose group) in the intestines of diabetic mice. This study reveals that mogroside can relieve T2DM, regulating intestinal flora and improving intestinal mucosal barrier, indicating that mogroside can be a potential therapeutic agent or intestinal microbiota regulator in the treatment of T2DM.

Effects of CDDO-EA in sepsis-induced acute lung injury: mouse model of endotoxaemia.

OBJECTIVE: Aim: The aim of this research is to clarify the potential effect of CDDO-EA against experimentally sepsis induced lung injury in mice. PATIENTS AND METHODS: Materials and Methods: Mice have divided into four groups: Sham group CLP group, Vehicle-treatment group, CDDO-EA-treated group: mice in this group received CDDO-EA 2mg/kg intraperitoneally, 1hr before CLP, then the animals were sacrificed 24hr after CLP. After exsAngpuinations, tissue samples of lung were collected, followed by markers measurement including, TNF-α, IL-1ß, VEGF, MPO, caspase11, Angp-1and Angp-2 by ELISA, gene expression of TIE2 and VE-cadherin by qRT-PCR, in addition to histopathological study. RESULTS: Results: A significant elevation (p<0.05) in TNF-α, IL-1ß, MPO, ANGP-2, VEGF, CASPASE 11 in CLP and vehicle groups when compared with sham group. CDDO-EA group showed significantly lower levels p<0.05, level of ANGP-1 was significantly lower p<0.05 in the CLP and vehicle groups as compared with the sham group. Quantitative real-time PCR demonstrated a significant decrement in mRNA expression of TIE2&ve-cadherin genes p<0.05 in sepsis & vehicle. CONCLUSION: Conclusions: CDDO-EA has lung protective effects due to its anti-inflammatory and antiAngpiogenic activity, additionally, CDDO-EA showes a lung protective effect as they affect tissue mRNA expression of TIE2 and cadherin gene. Furthermore, CDDO-EA attenuate the histopathological changes that occur during polymicrobial sepsis thereby lung protection effect.

Nucleolin myocardial-specific knockout exacerbates glucose metabolism disorder in endotoxemia-induced myocardial injury.

Background: Sepsis-induced myocardial injury, as one of the important complications of sepsis, can significantly increase the mortality of septic patients. Our previous study found that nucleolin affected mitochondrial function in energy synthesis and had a protective effect on septic cardiomyopathy in mice. During sepsis, glucose metabolism disorders aggravated myocardial injury and had a negative effect on septic patients. Objectives: We investigated whether nucleolin could regulate glucose metabolism during endotoxemia-induced myocardial injury. Methods: The study tested whether the nucleolin cardiac-specific knockout in the mice could affect glucose metabolism through untargeted metabolomics, and the results of metabolomics were verified experimentally in H9C2 cells. The ATP content, lactate production, and oxygen consumption rate (OCR) were evaluated. Results: The metabolomics results suggested that glycolytic products were increased in endotoxemia-induced myocardial injury, and that nucleolin myocardial-specific knockout altered oxidative phosphorylation-related pathways. The experiment data showed that TNF-α combined with LPS stimulation could increase the lactate content and the OCR values by about 25%, and decrease the ATP content by about 25%. However, interference with nucleolin expression could further decrease ATP content and OCR values by about 10-20% and partially increase the lactate level in the presence of TNF-α and LPS. However, nucleolin overexpression had the opposite protective effect, which partially reversed the decrease in ATP content and the increase in lactate level. Conclusion: Down-regulation of nucleolin can exacerbate glucose metabolism disorders in endotoxemia-induced myocardial injury. Improving glucose metabolism by regulating nucleolin was expected to provide new therapeutic ideas for patients with septic cardiomyopathy.

Central angiotensin-(1-7) attenuates hypoglycemia in sepsis-like conditions via reducing systemic and hepatic inflammation.

Sepsis is understood as the result of initiating systemic inflammation derived from an inadequate host response against pathogens. In its acute phase, sepsis is marked by an exacerbated reaction to infection, tissue damage, organ failure, and metabolic dysfunction. Among these, hypoglycemia, characterized by disorders of the gluconeogenesis pathway, is related to one of the leading causes of mortality in septic patients. Recent research has investigated the involvement of sympathetic efferent neuroimmune pathways during systemic inflammation. These pathways can be stimulated by several centrally administered drugs, including Angiotensin-(1-7) (Ang-(1-7)). Therefore, the present study aims to evaluate the effects of central treatment with Ang-(1-7) on hypoglycemia during endotoxemia. For this, male Wistar Hannover rats underwent stereotaxic surgery for intracerebroventricular (i.c.v.) administration of Ang-(1-7) and cannulation of the jugular vein for lipopolysaccharide (LPS) injection. Our results demonstrate that LPS was capable of inducing hypoglycemia and that prior central treatment with Ang-(1-7) attenuated this effect. Our data also show that Ang-(1-7) reduced plasma concentrations of TNF-α, IL-1ß, IL-6, and nitric oxide, in addition to the decrease and increase of hepatic IL-6 and IL-10 respectively, in animals subjected to systemic inflammation by LPS, resulting in the reduction of systemic and hepatic inflammation, thus attenuating the deleterious effects of LPS on phosphoenolpyruvate carboxykinase protein content. In summary, the data suggest that central treatment with Ang-(1-7) attenuates hypoglycemia induced by endotoxemia, probably through anti-inflammatory action, leading to reestablishing hepatic gluconeogenesis.

Cardiolipin oxidized by ROS from complex II acts as a target of gasdermin D to drive mitochondrial pore and heart dysfunction in endotoxemia.

Cardiac dysfunction, an early complication of endotoxemia, is the major cause of death in intensive care units. No specific therapy is available at present for this cardiac dysfunction. Here, we show that the N-terminal gasdermin D (GSDMD-N) initiates mitochondrial apoptotic pore and cardiac dysfunction by directly interacting with cardiolipin oxidized by complex II-generated reactive oxygen species (ROS) during endotoxemia. Caspase-4/11 initiates GSDMD-N pores that are subsequently amplified by the upregulation and activation of NLRP3 inflammation through further generation of ROS. GSDMD-N pores form prior to BAX and VDAC1 apoptotic pores and further incorporate into BAX and VDAC1 oligomers within mitochondria membranes to exacerbate the apoptotic process. Our findings identify oxidized cardiolipin as the definitive target of GSDMD-N in mitochondria of cardiomyocytes during endotoxin-induced myocardial dysfunction (EIMD), and modulation of cardiolipin oxidation could be a therapeutic target early in the disease process to prevent EIMD.

A novel fatty acid analogue triggers CD36-GPR120 interaction and exerts anti-inflammatory action in endotoxemia.

Inflammation is a mediator of a number of chronic pathologies. We synthesized the diethyl (9Z,12Z)-octadeca-9,12-dien-1-ylphosphonate, called NKS3, which decreased lipopolysaccharide (LPS)-induced mRNA upregulation of proinflammatory cytokines (IL-1ß, IL-6 and TNF-α) not only in primary intraperitoneal and lung alveolar macrophages, but also in freshly isolated mice lung slices. The in-silico studies suggested that NKS3, being CD36 agonist, will bind to GPR120. Co-immunoprecipitation and proximity ligation assays demonstrated that NKS3 induced protein-protein interaction of CD36 with GPR120in RAW 264.7 macrophage cell line. Furthermore, NKS3, via GPR120, decreased LPS-induced activation of TAB1/TAK1/JNK pathway and the LPS-induced mRNA expression of inflammatory markers in RAW 264.7 cells. In the acute lung injury model, NKS3 decreased lung fibrosis and inflammatory cytokines (IL-1ß, IL-6 and TNF-α) and nitric oxide (NO) production in broncho-alveolar lavage fluid. NKS3 exerted a protective effect on LPS-induced remodeling of kidney and liver, and reduced circulating IL-1ß, IL-6 and TNF-α concentrations. In a septic shock model, NKS3 gavage decreased significantly the LPS-induced mortality in mice. In the last, NKS3 decreased neuroinflammation in diet-induced obese mice. Altogether, these results suggest that NKS3 is a novel anti-inflammatory agent that could be used, in the future, for the treatment of inflammation-associated pathologies.

Propofol and Dexmedetomidine Ameliorate Endotoxemia-Associated Encephalopathy via Inhibiting Ferroptosis.

Background: Sepsis is recognized as a multiorgan and systemic damage caused by dysregulated host response to infection. Its acute systemic inflammatory response highly resembles that of lipopolysaccharide (LPS)-induced endotoxemia. Propofol and dexmedetomidine are two commonly used sedatives for mechanical ventilation in critically ill patients and have been reported to alleviate cognitive impairment in many diseases. In this study, we aimed to explore and compare the effects of propofol and dexmedetomidine on the encephalopathy induced by endotoxemia and to investigate whether ferroptosis is involved, finally providing experimental evidence for multi-drug combination in septic sedation. Methods: A total of 218 C57BL/6J male mice (20-25 g, 6-8 weeks) were used. Morris water maze (MWM) tests were performed to evaluate whether propofol and dexmedetomidine attenuated LPS-induced cognitive deficits. Brain injury was evaluated using Nissl and Fluoro-Jade C (FJC) staining. Neuroinflammation was assessed by dihydroethidium (DHE) and DCFH-DA staining and by measuring the levels of three cytokines. The number of Iba1+ and GFAP+ cells was used to detect the activation of microglia and astrocytes. To explore the involvement of ferroptosis, the levels of ptgs2 and chac1; the content of iron, malondialdehyde (MDA), and glutathione (GSH); and the expression of ferroptosis-related proteins were investigated. Conclusion: The single use of propofol and dexmedetomidine mitigated LPS-induced cognitive impairment, while the combination showed poor performance. In alleviating endotoxemic neural loss and degeneration, the united sedative group exhibited the most potent capability. Both propofol and dexmedetomidine inhibited neuroinflammation, while propofol's effect was slightly weaker. All sedative groups reduced the neural apoptosis, inhibited the activation of microglia and astrocytes, and relieved neurologic ferroptosis. The combined group was most prominent in combating genetic and biochemical alterations of ferroptosis. Fpn1 may be at the core of endotoxemia-related ferroptosis activation.

Perception of unfamiliar caregivers during sickness - Using the new Caregiver Perception Task (CgPT) during experimental endotoxemia.

Social withdrawal is a well-established part of sickness behavior, but in some contexts sick animals might gain from keeping close instead of keeping away. For instance, sick individuals are more willing to be near known individuals who can provide care and safety (close others) compared to when healthy. Yet, interactions with some strangers might also be beneficial (i.e., healthcare professionals), but it is not known how sickness interplay with social behavior towards such individuals. Here, we assessed if sickness affects perception of caregivers, and developed a new task, the Caregiver Perception Task (CgPT). Twenty-six participants performed the CgPT, once after an injection of lipopolysaccharide (LPS, 0.8 ng/kg body weight, n = 24), and once after an injection of saline (n = 25), one hour and forty-five minutes post-injection. During the task, participants watched short video clips of three types of caregivers: a healthcare professional taking care of a sick individual, a healthcare professional not taking care of a sick individual, and a non-healthcare professional taking care of their sick adult child or partner. After each video clip, the likability, trustworthiness, professionalism, and willingness to interact with and receive care from the caregiver were rated on visual analogue scales. Results showed that participants injected with saline rated healthcare professionals who did not take care of a sick individual less positively on all aspects compared to healthcare professionals who took care of a sick individual. Moreover, compared to saline, LPS increased the participants' willingness to receive care from healthcare professionals and non-healthcare professionals providing care, but not from healthcare professionals not providing care. Thus, our results indicate that sick individuals may approach unknown individuals with potential to provide care and support.

Biomolecular Actions by Intestinal Endotoxemia in Metabolic Syndrome.

Metabolic syndrome (MetS) is a combination of metabolic disorders that concurrently act as factors promoting systemic pathologies such as atherosclerosis or diabetes mellitus. It is now believed to encompass six main interacting conditions: visceral fat, imbalance of lipids (dyslipidemia), hypertension, insulin resistance (with or without impairing both glucose tolerance and fasting blood sugar), and inflammation. In the last 10 years, there has been a progressive interest through scientific research investigations conducted in the field of metabolomics, confirming a trend to evaluate the role of the metabolome, particularly the intestinal one. The intestinal microbiota (IM) is crucial due to the diversity of microorganisms and their abundance. Consequently, IM dysbiosis and its derivate toxic metabolites have been correlated with MetS. By intervening in these two factors (dysbiosis and consequently the metabolome), we can potentially prevent or slow down the clinical effects of the MetS process. This, in turn, may mitigate dysregulations of intestinal microbiota axes, such as the lung axis, thereby potentially alleviating the negative impact on respiratory pathology, such as the chronic obstructive pulmonary disease. However, the biomolecular mechanisms through which the IM influences the host's metabolism via a dysbiosis metabolome in both normal and pathological conditions are still unclear. In this study, we seek to provide a description of the knowledge to date of the IM and its metabolome and the factors that influence it. Furthermore, we analyze the interactions between the functions of the IM and the pathophysiology of major metabolic diseases via local and systemic metabolome's relate endotoxemia.

A novel blood-based bioassay to monitor adiponectin signaling.

The diverse beneficial effects of adiponectin-receptor signaling, including its impact on the regulation of inflammatory processes in vivo, have resulted in development of adiponectin receptor agonists as a treatment for metabolic disorders. However, there are no established non-invasive bioassays for detection of adiponectin target engagement in humans or animal models. Here, we designed an assay using small amounts of blood to assess adiponectin action. Specifically, we tested effects of the small 10-amino acid peptide adiponectin receptor agonist, ALY688, in a sublethal LPS endotoxemia model in mice. LPS-induced pro-inflammatory cytokine levels in serum were significantly reduced in mice treated with ALY688, assessed via multiplex ELISA in flow cytometry. Furthermore, ALY688 alone significantly induced TGF-ß release in serum 1 h after treatment and was elevated for up to 24 h. Additionally, using a flow-cytometry panel for detection of changes in circulating immune cell phenotypes, we observed a significant increase in absolute T cell counts in mice after ALY688 treatment. To assess changes in intracellular signaling effectors downstream of adiponectin, phospho-flow cytometry was conducted. There was a significant increase in phosphorylation of AMPK and p38-MAPK in mice after ALY688 treatment. We then used human donor immune cells (PBMCs) treated with ALY688 ex vivo and observed elevation of AMPK and p38-MAPK phosphorylation from baseline in response to ALY688. Together, these results indicate we can detect adiponectin action on immune cells in vivo by assessing adiponectin signaling pathway for AMPK and p38-MAPK, as well as pro-inflammatory cytokine levels. This new approach provides a blood-based bioassay for screening adiponectin action.

Potential Therapeutic Strategies and Drugs That Target Vascular Permeability in Severe Infectious Diseases.

Severe infection pathogenicity is induced by processes such as pathogen exposure, immune cell activation, inflammatory cytokine production, and vascular hyperpermeability. Highly effective drugs, such as antipathogenic agents, steroids, and antibodies that suppress cytokine function, have been developed to treat the first three processes. However, these drugs cannot completely suppress severe infectious diseases, such as coronavirus disease 2019 (COVID-19). Therefore, developing novel drugs that inhibit vascular hyperpermeability is crucial. This review summarizes the mechanisms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced vascular hyperpermeability and identifies inhibitors that increase endothelial cell (EC) junction-related proteins and determines their efficacy in COVID-19 and endotoxemia models. Analyzing the effects of SARS-CoV-2 on vascular permeability revealed that SARS-CoV-2 suppresses Claudin-5 (CLDN5) expression, which is responsible for adhesion between ECs, thereby increasing vascular permeability. Inhibiting CLDN5 function in mice induced vascular hyperpermeability and pulmonary edema. In contrast, Enhancing CLDN5 expression suppressed SARS-CoV-2-induced endothelial hyperpermeability, suggesting that SARS-CoV-2-induced vascular hyperpermeability contributes to pathological progression, which can be suppressed by upregulating EC junction proteins. Based on these results, we focused on Roundabout4 (Robo4), another EC-specific protein that stabilizes EC junctions. EC-specific Robo4 overexpression suppressed vascular hyperpermeability and mortality in lipopolysaccharide-treated mice. An ALK1 inhibitor (a molecule that increases Robo4 expression), suppressed vascular hyperpermeability and mortality in lipopolysaccharide- and SARS-CoV-2-treated mice. These results indicate that Robo4 expression-increasing drugs suppress vascular permeability and pathological phenotype in COVID-19 and endotoxemia models.

Intestinal epithelial Krüppel-like factor 4 alleviates endotoxemia and atherosclerosis through improving NF-κB/miR-34a-mediated intestinal permeability.

Maintenance of intestinal barrier function contributes to gastrointestinal homeostasis and therefore cardiovascular diseases. A number of studies show that intestinal permeability is affected by excessive inflammatory responses. Krüppel-like factor (KLF) 4 is one of the critical transcriptional factors, which controls multiple immune responses. In this study we investigated the role of KLF4 in regulating intestinal inflammation and permeability during the atherosclerotic process. Atherosclerotic model was established in ApoE-/- mice by feeding a high fat high cholesterol (HFHC) diet. We showed that colon expression levels of KLF4 and tight junction proteins were significantly decreased whereas inflammatory responses increased in atherosclerotic mice. Overexpression of colon epithelial Klf4 decreased atherosclerotic plaque formation and vascular inflammation in atherosclerotic mice, accompanied by remarkable suppression of intestinal NF-κB activation. We found that overexpression of epithelial Klf4 in atherosclerotic mice significantly increased intestinal tight junction expression and ameliorated endotoxemia, whereas replenishment of LPS abolished these benefits. Overexpression of Klf4 reversed LPS-induced permeability and downregulation of ZO-1 and Occludin in Caco-2 cells in vitro. HFHC diet stimulated the expression of epithelial microRNA-34a, whereas silence of epithelial Klf4 abolished the benefits of microRNA-34a sponge, a specific miR-34a inhibitor, on intestinal permeability and atherosclerotic development. A clinical cohort of 24 atherosclerotic patients supported colon KLF4/NF-κB/tight junction protein axis mediated intestine/cardiovascular interaction in patients with atherosclerosis. Taken together, intestinal epithelial KLF4 protects against intestinal inflammation and barrier dysfunction, ameliorating atherosclerotic plaque formation.

Thromboelastographic evaluation of the effectiveness of choline or CDP-choline treatment on endotoxin-induced hemostatic alterations in dogs.

Sepsis/endotoxemia associates with coagulation abnormalities. We showed previously that exogenous choline treatment reversed the changes in platelet count and function as well as prevented disseminated intravascular coagulation (DIC) in endotoxemic dogs. The aim of this follow-up study was to evaluate the effect of treatment with choline or cytidine-5'-diphosphocholine (CDP-choline), a choline donor, on endotoxin-induced hemostatic alterations using thromboelastography (TEG). Dogs were randomized to six groups and received intravenously (iv) saline, choline (20 mg/kg) or CDP-choline (70 mg/kg) in the control groups, whereas endotoxin (0.1 mg/kg, iv) was used alone or in combination with choline or CDP-choline at the same doses in the treatment groups. TEG variables including R- and K-time (clot formation), maximum amplitude (MA) and α-angle (clot stability), G value (clot elasticity), and EPL, A, and LY30 (fibrinolysis), as well as overall assessment of coagulation (coagulation index - CI), were measured before and at 0.5-48 h after the treatments. TEG parameters did not change significantly in the control groups, except for CI parameter after choline administration. Endotoxemia resulted in increased R-time and A value (P < 0.05), decreased K-time (P < 0.05), α-angle (P < 0.001) and CI values (P < 0.01) at different time points. Treatment with either choline or CDP-choline attenuated or prevented completely the alterations in TEG parameters in endotoxemic dogs with CDP-choline being more effective. These results confirm and extend the effectiveness of choline or CDP-choline in endotoxemia by further demonstrating their efficacy in attenuating or preventing the altered viscoelastic properties of blood clot measured by TEG.

A green tea extract confection decreases circulating endotoxin and fasting glucose by improving gut barrier function but without affecting systemic inflammation: A double-blind, placebo-controlled randomized trial in healthy adults and adults with metabolic syndrome.

Anti-inflammatory activities of catechin-rich green tea extract (GTE) in obese rodents protect against metabolic endotoxemia by decreasing intestinal permeability and absorption of gut-derived endotoxin. However, translation to human health has not been established. We hypothesized that GTE would reduce endotoxemia by decreasing gut permeability and intestinal and systemic inflammation in persons with metabolic syndrome (MetS) compared with healthy persons. A randomized, double-blind, placebo-controlled, crossover trial in healthy adults (n = 19, 34 ± 2 years) and adults with MetS (n = 21, 40 ± 3 years) examined 4-week administration of a decaffeinated GTE confection (890 mg/d total catechins) on serum endotoxin, intestinal permeability, gut and systemic inflammation, and cardiometabolic parameters. Compared with the placebo, the GTE confection decreased serum endotoxin (P = .023) in both healthy persons and those with MetS, while increasing concentrations of circulating catechins (P < .0001) and γ-valerolactones (P = .0001). Fecal calprotectin (P = .029) and myeloperoxidase (P = .048) concentrations were decreased by GTE regardless of health status. Following the ingestion of gut permeability probes, urinary lactose/mannitol (P = .043) but not sucralose/erythritol (P > .05) was decreased by GTE regardless of health status. No between-treatment differences (P > .05) were observed for plasma aminotransferases, blood pressure, plasma lipids, or body mass nor were plasma tumor necrosis factor-α, interleukin-6, or the ratio of lipopolysaccharide-binding protein/soluble cluster of differentiation-14 affected. However, fasting glucose in both study groups was decreased (P = .029) by the GTE confection compared with within-treatment arm baseline concentrations. These findings demonstrate that catechin-rich GTE is effective to decrease circulating endotoxin and improve glycemic control in healthy adults and those with MetS, likely by reducing gut inflammation and small intestinal permeability but without affecting systemic inflammation.

The protective effects of naringenin, a citrus flavonoid, non-complexed or complexed with hydroxypropyl-ß-cyclodextrin against multiorgan damage caused by neonatal endotoxemia.

BACKGROUND: Endotoxemia is a severe and dangerous clinical syndrome that results in elevated morbidity, especially in intensive care units. Neonates are particularly susceptible to endotoxemia due to their immature immune systems. There are few effective treatments for neonatal endotoxemia. One group of compounds with potential in the treatment of neonatal inflammatory diseases such as endotoxemia is the flavonoids, mainly due to their antioxidant and anti-inflammatory properties. Among these, naringenin (NGN) is a citrus flavonoid which has already been reported to have anti-inflammatory, antioxidant, anti-nociceptive and anti-cancer effects. Unfortunately, its clinical application is limited by its low solubility and bioavailability. However, cyclodextrins (CDs) have been widely used to improve the solubility of nonpolar drugs and enhance the bioavailability of these natural products. OBJECTIVE: We, therefore, aimed to investigate the effects of NGN non-complexed and complexed with hydroxypropyl-ß-cyclodextrin (HPßCD) on neonatal endotoxemia injuries in a rodent model and describe the probable molecular mechanisms involved in NGN activities. METHOD: We used exposure to a bacterial lipopolysaccharide (LPS) to induce neonatal endotoxemia in the mice. RESULTS: It was found that NGN (100 mg/kg i.p.) exposure during the neonatal period reduced leukocyte migration and decreased pro-inflammatory cytokine (TNF-α, IL-1ß and IL-6) levels in the lungs, heart, kidneys or cerebral cortex. In addition, NGN upregulated IL-10 production in the lungs and kidneys of neonate mice. The administration of NGN also enhanced antioxidant enzyme catalase and SOD activity, reduced lipid peroxidation and protein carbonylation and increased the reduced sulfhydryl groups in an organ-dependent manner, attenuating the oxidative damage caused by LPS exposure. NGN decreased ERK1/2, p38MAPK and COX-2 activation in the lungs of neonate mice. Moreover, NGN complexed with HPßCD was able to increase the animal survival rate. CONCLUSION: NGN attenuated inflammatory and oxidative damage in the lungs, heart and kidneys caused by neonatal endotoxemia through the MAPK signaling pathways regulation. Our results show that NGN has beneficial effects against neonatal endotoxemia and could be useful in the treatment of neonatal inflammatory injuries.

Diminazene aceturate attenuates systemic inflammation via microbiota gut-5-HT brain-spleen sympathetic axis in male mice.

The sympathetic arm of the inflammatory reflex is the efferent pathway through which the central nervous system (CNS) can control peripheral immune responses. Diminazene aceturate (DIZE) is an antiparasitic drug that has been reported to exert protective effects on various experimental models of inflammation. However, the pathways by which DIZE promotes a protective immunomodulatory effects still need to be well established, and no studies demonstrate the capacity of DIZE to modulate a neural reflex to control inflammation. C57BL/6 male mice received intraperitoneal administration of DIZE (2 mg/Kg) followed by lipopolysaccharide (LPS, 5 mg/Kg, i.p.). Endotoxemic animals showed hyperresponsiveness to inflammatory signals, while those treated with DIZE promoted the activation of the inflammatory reflex to attenuate the inflammatory response during endotoxemia. The unilateral cervical vagotomy did not affect the anti-inflammatory effect of DIZE in the spleen and serum. At the same time, splenic denervation attenuated tumor necrosis factor (TNF) synthesis in the spleen and serum. Using broad-spectrum antibiotics for two weeks showed that LPS modulated the microbiota to induce a pro-inflammatory profile in the intestine and reduced the serum concentration of tryptophan and serotonin (5-HT), while DIZE restored serum tryptophan and increased the hypothalamic 5-HT levels. Furthermore, the treatment with 4-Chloro-DL-phenylalanine (pcpa, an inhibitor of 5-HT synthesis) abolished the anti-inflammatory effects of the DIZE in the spleen. Our results indicate that DIZE promotes microbiota modulation to increase central 5-HT levels and activates the efferent sympathetic arm of the inflammatory reflex to control splenic TNF production in endotoxemic mice.

Pregnane X Receptor Activation in Liver Macrophages Protects against Endotoxin-Induced Liver Injury.

Endotoxemia-related acute liver injury has a poor prognosis and high mortality, and macrophage polarization plays a central role in the pathological process. Pregnane X receptor (PXR) serves as a nuclear receptor and xenosensor, safeguarding the liver from toxic stimuli. However, the effect and underlying mechanism of PXR activation on endotoxemic liver injury remain largely unknown. Here, the expression of PXR is reported in human and murine macrophages, and PXR activation modified immunotypes of macrophages. Moreover, PXR activation significantly attenuated endotoxemic liver injury and promoted macrophage M2 polarization. Macrophage depletion by GdCl3 confirmed the essential of macrophages in the beneficial effects observed with PXR activation. The role of PXR in macrophages is further validated using AAV8-F4/80-Pxr shRNA-treated mice; the PXR-mediated hepatoprotection is impaired, and M2 polarization enhancement is blunted. Additionally, treatment with PXR agonists inhibited lipopolysaccharide (LPS)-induced M1 polarization and favored M2 polarization in BMDM, Raw264.7, and THP-1 cells. Further analyses revealed an interaction between PXR and p-STAT6 in vivo and in vitro. Moreover, blocking Pxr or Stat6 abolished the PXR-induced polarization shift. Collectively, macrophage PXR activation attenuated endotoxin-induced liver injury and regulated macrophage polarization through the STAT6 signaling pathway, which provided a potential therapeutic target for managing endotoxemic liver injury.

Imaging quantitative changes in blood-brain barrier permeability using [18F]2-fluoro-2-deoxy-sorbitol ([18F]FDS) PET in relation to glial cell recruitment in a mouse model of endotoxemia.

The quantitative relationship between the disruption of the blood-brain barrier (BBB) and the recruitment of glial cells was explored in a mouse model of endotoxemia. [18F]2-Fluoro-2-deoxy-sorbitol ([18F]FDS) PET imaging was used as a paracellular marker for quantitative monitoring of BBB permeability after i.v injection of increasing doses of lipopolysaccharide (LPS) or vehicle (saline, n = 5). The brain distribution of [18F]FDS (VT, mL.cm-3) was estimated using kinetic modeling. LPS dose-dependently increased the brain VT of [18F]FDS after injection of LPS 4 mg/kg (5.2 ± 2.4-fold, n = 4, p < 0.01) or 5 mg/kg (9.0 ± 9.1-fold, n = 4, p < 0.01) but not 3 mg/kg (p > 0.05, n = 7). In 12 individuals belonging to the different groups, changes in BBB permeability were compared with expression of markers of astrocyte (GFAP) and microglial cell (CD11b) using ex vivo immunohistochemistry. Increased expression of CD11b and GFAP expression was observed in mice injected with 3 mg/kg of LPS, which did not increase with higher LPS doses. Quantitative [18F]FDS PET imaging can capture different levels of BBB permeability in vivo. A biphasic effect was observed with the lowest dose of LPS that triggered neuroinflammation without disruptive changes in BBB permeability, and higher LPS doses that increased BBB permeability without additional recruitment of glial cells.