NF-kappaB and p38 MAPK inhibition improve survival in endotoxin shock and in a cecal ligation and puncture model of sepsis in combination with antibiotic therapy

Jiawei Shengjiangsan's Effect on Renal Injury in Diabetic Nephropathy Mice is Investigated via the PI3K/Akt/NF-κB Signaling Pathway

Purpose

This study aimed to investigate the intervention mechanism of Jiawei Shengjiangsan (JWSJS) on kidney injury in diabetic nephropathy mice.

Methods

Thirty 8-week-old db/db mice were randomly divided into five groups: model group, Perindopril group, and JWSJS low-, medium-, and high-dose groups (n=6 per group) based on body weight. Additionally, a blank control group was established consisting of 6 db/m mice aged 8 weeks. The blank and model groups received daily intragastric administration of 7g/kg/d pure water. The remaining groups were assigned to JWSJS low (3.5g/kg/d), medium (7g/kg/d), high (14g/kg/d) dosage groups, and perindopril positive control group (0.48mg/kg/d) for 12 weeks. Post-experiment, serum creatinine (SCr) and blood urea nitrogen (BUN) were analyzed using an automatic biochemical analyzer. Enzyme-linked immunosorbent assay (ELISA) measured 24-hour urinary albumin, neutrophil gelatinase-associated lipocalin (NGAL), TNF-α, IL-1β, VCAM-1, MCP-1, and HbA1c. Western blot assessed the protein expressions of p-PI3K, p-Akt, and p-NF-κB p65, while pathological kidney changes were observed.

Results

Compared to the blank group, the model group exhibited increased SCr, BUN, 24-hour urinary albumin, serum NGAL, TNF-α, IL-1β, VCAM-1, MCP-1, HbA1c, p-PI3K, and p-Akt, alongside increased p-NF-κB p65 expression, indicating significant kidney pathology. After treatment, the JWSJS group showed decreased SCr, BUN, 24-hour urinary microalbumin, NGAL, HbA1c, TNF-α, IL-1β, VCAM-1, MCP-1 levels, increased p-PI3K and p-Akt expression (P<0.05), and reduced p-NF-κB p65 content (P<0.05). Histopathological analysis revealed that JWSJS ameliorated renal tubular epithelial cell damage, glomerular capillary and basement membrane injuries, and facilitated the repair of damaged podocytes in diabetic nephropathy mice.

Conclusion

JWSJS demonstrated efficacy in reducing renal inflammation in diabetic nephropathy mice, with its mechanism likely associated with the inhibition of the PI3K/Akt/NF-κB signaling pathway.

Tomatidine activates autophagy to improve lung injury and inflammation in sepsis by inhibiting NF-κB and MAPK pathways

Sepsis-induced acute lung injury (ALI) is a life-threatening medical condition with high mortality and morbidity. Autophagy is involved in the pathophysiological process of sepsis-induced ALI, including inflammation, which indicates that regulating autophagy may be beneficial for this disease. Tomatidine, a natural compound abundant in unripe tomatoes, has been reported to have anti-inflammatory, anti-tumorigenic, and lipid-lowering effects. However, the biological functions and mechanisms of tomatidine in sepsis-induced ALI remain unknown. The principal objective of this study was to investigate the effect of tomatidine on sepsis-induced ALI. Cecal ligation and puncture (CLP) was used to induce septic lung injury in mice, and 10 mg/kg tomatidine was intraperitoneally injected into mice 2 h after the operation. The results of hematoxylin and eosin staining and assessment of lung edema and total protein levels in bronchoalveolar lavage fluid (BALF) demonstrated that tomatidine alleviated CLP-induced severe lung injuries such as hemorrhage, infiltration of inflammatory cells, and interstitial and alveolar edema in mice. Additionally, the levels of proinflammatory cytokines in BALF and lung tissues were measured by enzyme-linked immunosorbent assay (ELISA), and the results showed that tomatidine inhibited CLP-induced inflammatory damage to lungs. Moreover, the results of western blotting showed that tomatidine promoted autophagy during CLP-induced ALI. Mechanistically, immunofluorescence staining and western blotting were used to measure the protein levels of TLR4, phosphorylated NF-κB, phosphorylated IκBα, and phosphorylated MAPKs, showing that tomatidine inactivated NF-κB and MAPK signaling in lung tissues of CLP-induced ALI mice. In conclusion, tomatidine exerts protective effects against sepsis-induced severe damage to the lungs by inhibiting inflammation and activating autophagy in CLP-treated mice through inactivating the NF-κB and MAPK pathways, which may be an effective candidate for treating septic ALI.

Activation of thousands of genes in the lungs and kidneys by sepsis is countered by the selective nuclear blockade

The steady rise of sepsis globally has reached almost 49 million cases in 2017, and 11 million sepsis-related deaths. The genomic response to sepsis comprising multi-system stage of raging microbial inflammation has been reported in the whole blood, while effective treatment is lacking besides anti-microbial therapy and supportive measures. Here we show that, astoundingly, 6,237 significantly expressed genes in sepsis are increased or decreased in the lungs, the site of acute respiratory distress syndrome (ARDS). Moreover, 5,483 significantly expressed genes in sepsis are increased or decreased in the kidneys, the site of acute injury (AKI). This massive genomic response to polymicrobial sepsis is countered by the selective nuclear blockade with the cell-penetrating Nuclear Transport Checkpoint Inhibitor (NTCI). It controlled 3,735 sepsis-induced genes in the lungs and 1,951 sepsis-induced genes in the kidneys. The NTCI also reduced without antimicrobial therapy the bacterial dissemination: 18-fold in the blood, 11-fold in the lungs, and 9-fold in the spleen. This enhancement of bacterial clearance was not significant in the kidneys. Cumulatively, identification of the sepsis-responsive host's genes and their control by the selective nuclear blockade advances a better understanding of the multi-system mechanism of sepsis. Moreover, it spurs much-needed new diagnostic, therapeutic, and preventive approaches.

Pharmacological Potential of Betulin as a Multitarget Compound

Betulin is a natural triterpene, usually from birch bark, known for its potential wound-healing properties. Despite having a wide range of pharmacological targets, no studies have proposed betulin as a multitarget compound. Betulin has protective effects against cardiovascular and liver diseases, cancer, diabetes, oxidative stress, and inflammation. It reduces postprandial hyperglycemia by inhibiting α-amylase and α-glucosidase activity, combats tumor cells by inducing apoptosis and inhibiting metastatic proteins, and modulates chronic inflammation by blocking the expression of proinflammatory cytokines via modulation of the NFκB and MAPKs pathways. Given its potential to influence diverse biological networks with high target specificity, it can be hypothesized that betulin may eventually become a new lead for drug development because it can modify a variety of pharmacological targets. The summarized research revealed that the diverse beneficial effects of betulin in various diseases can be attributed, at least in part, to its multitarget anti-inflammatory activity. This review focuses on the natural sources, pharmacokinetics, pharmacological activity of betulin, and the multi-target effects of betulin on signaling pathways such as MAPK, NF-κB, and Nrf2, which are important regulators of the response to oxidative stress and inflammation in the body.

Assessment of sulfamethoxazole toxicity to marine mussels (Mytilus galloprovincialis): Combine p38-MAPK signaling pathway modulation with histopathological alterations

Sulfamethoxazole (SMX), is a ubiquitous antibiotic in the aquatic environment and received concerns on its health hazards, especially its sub-lethal effects on non-target organisms which were remained largely unknown. In the present study, in order to investigate SMX induced tissue damages and reveal underlying mechanisms, marine mussels, Mytilus galloprovincialis were challenged to SMX series (0.5, 50 and 500 μg/L) for six-days followed by six-day-recovery. Comprehensive histopathological alteration (including qualitative, semi-quantitative and quantitative indices), together with transcriptional and (post-) translational responses of key factors (p38, NFκB and p53) in the p38-MAPK signaling pathway were analyzed in gills and digestive glands. Tissue-specific responses were clearly investigated with gills showing more prompt responses and digestive glands showing higher tolerance to SMX. The histopathology showed that SMX triggered inflammatory damages in both tissues and quantitative analysis revealed more significant responses, suggesting its potential as a valuable health indicator. SMX activated expressions of p38, NFκB and p53 at transcriptional and (post-) translational levels, especially after exposed to low level SMX, evidenced by p38 coupled with NFκB/p53 regulation on immunity defense in mussels. Less induction of targeted molecules under severe SMX exposure indicated such signaling transduction may not be efficient enough and can result in inflammatory damages. Taken together, this study expanded the understanding of aquatic SMX induced health risk in marine mussels and the underlying regulation mechanism through p38 signaling transduction.

ICOS-Fc as innovative immunomodulatory approach to counteract inflammation and organ injury in sepsis

Inducible T cell co-stimulator (ICOS), an immune checkpoint protein expressed on activated T cells and its unique ligand, ICOSL, which is expressed on antigen-presenting cells and non-hematopoietic cells, have been extensively investigated in the immune response. Recent findings showed that a soluble recombinant form of ICOS (ICOS-Fc) can act as an innovative immunomodulatory drug as both antagonist of ICOS and agonist of ICOSL, modulating cytokine release and cell migration to inflamed tissues. Although the ICOS-ICOSL pathway has been poorly investigated in the septic context, a few studies have reported that septic patients have reduced ICOS expression in whole blood and increased serum levels of osteopontin (OPN), that is another ligand of ICOSL. Thus, we investigated the pathological role of the ICOS-ICOSL axis in the context of sepsis and the potential protective effects of its immunomodulation by administering ICOS-Fc in a murine model of sepsis. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP) in five-month-old male wild-type (WT) C57BL/6, ICOS-/-, ICOSL-/- and OPN-/- mice. One hour after the surgical procedure, either CLP or Sham (control) mice were randomly assigned to receive once ICOS-Fc, F119SICOS-Fc, a mutated form uncapable to bind ICOSL, or vehicle intravenously. Organs and plasma were collected 24 h after surgery for analyses. When compared to Sham mice, WT mice that underwent CLP developed within 24 h a higher clinical severity score, a reduced body temperature, an increase in plasma cytokines (TNF-α, IL-1β, IL-6, IFN-γ and IL-10), liver injury (AST and ALT) and kidney (creatinine and urea) dysfunction. Administration of ICOS-Fc to WT CLP mice reduced all of these abnormalities caused by sepsis. Similar beneficial effects were not seen in CLP-mice treated with F119SICOS-Fc. Treatment of CLP-mice with ICOS-Fc also attenuated the sepsis-induced local activation of FAK, P38 MAPK and NLRP3 inflammasome. ICOS-Fc seemed to act at both sides of the ICOS-ICOSL interaction, as the protective effect was lost in septic knockout mice for the ICOS or ICOSL genes, whereas it was maintained in OPN knockout mice. Collectively, our data show the beneficial effects of pharmacological modulation of the ICOS-ICOSL pathway in counteracting the sepsis-induced inflammation and organ dysfunction.

Ascorbic acid and hydrocortisone synergistically inhibit septic organ injury via improving oxidative stress and inhibiting inflammation

BACKGROUND

The current study aimed to investigate the effect of the combination of ascorbic acid (AscA) and hydrocortisone (Hyd) on septic organ injury and its potential mechanism.

METHOD

Sepsis was induced in mice by a single intraperitoneal injection of lipopolysaccharides.

RESULTS

AscA and Hyd combined showed more effective protection of the injured liver and kidney in septic mice by decreasing ALT, AST, BUN and SCr and ameliorating pathological manifestations than Hyd or AscA alone. AscA showed a mild inhibitory effect on the secretion of proinflammatory cytokines (TNF-α, IL-1β and IL-6). However, Hyd showed a weak regulatory effect on septic oxidative stress markers (MDA, SOD and GSH-Px). However, the combination of AscA and Hyd showed a more powerful inhibitory effect on the septic inflammatory response and oxidative stress than Hyd or AscA alone by decreasing TNF-α, IL-1β and IL-6 and regulating MDA, SOD and GSH. In an in vitro study, cotreatment of RAW 264.7 macrophages with Hyd and AscA sharply reduced reactive oxygen species (ROS) generation and synergistically inhibited TNF-α, IL-1β and IL-6 secretion, which could be abolished by additional stimulation with the ROS donor 3-nitropropionic acid (3-NP). As expected, cotreatment of macrophages with Hyd and AscA synergistically inhibited the activation of p38 MAPK and p-p65, and the effect could be reversed by additional stimulation with 3-NP.

CONCLUSIONS

AscA and Hyd synergistically protect the kidney and liver from injury by inhibiting the inflammatory response and oxidative stress. The powerful inhibitory effects of AscA on oxidative stress contribute to the synergistic anti-inflammatory action.

Duchesnea indica Extract Ameliorates LPS-Induced Septic Shock in Mice

Objective

Duchesnea indica has been reported for its anti-inflammatory properties. However, its efficacy in sepsis has yet to be reported. In this study, we studied the ability of Duchesnea indica extract (DIE) to rescue mice from septic shock and sepsis.

Methods

In vitro studies included the measurement of secreted nitric oxide, cell viability, gene and protein expression via real-time polymerase chain reaction and western blot, and confocal microscopy in RAW 264.7 cells. In vivo studies include a model of septic shock and sepsis in BALB/c mice induced by a lethal and sub-lethal dose of lipopolysaccharide (LPS).

Results

DIE suppressed the expression of proinflammatory cytokines induced by LPS and prevented the translocation of NFκB into the nucleus of RAW 264.7 cells. It also prevented reactive oxygen species damage induced by LPS in murine bone marrow-derived macrophages. Models of sepsis and septic shock were established in BALB/c mice and DIE-rescued mice from septic shock. DIE also reversed the increase in tumor necrosis factor-α and nitrite levels in the serum of mice induced with sepsis. DIE also prevented the translocation of NFκB from the cytosol into the nucleus in murine lungs. Histopathological damage induced by sepsis was reversed in the testis, liver, and lungs of mice.

Conclusion

In conclusion, DIE is a suitable candidate for development as a therapeutic agent for sepsis.

Role of Mitochondria-Derived Danger Signals Released After Injury in Systemic Inflammation and Sepsis

Significance: Sepsis is a major public health concern, with high mortality and morbidity, especially among patients undergoing trauma. It is characterized by a systemic inflammatory response syndrome (SIRS) occurring in response to infection. Although classically associated with pathogens, many patients with SIRS do not have infection. The variability of the disease course cannot be fully explained by our current understanding of its pathogenesis. Thus, other factors are likely to play key roles in the development and progression of SIRS/sepsis. Recent Advances: Circulating levels of damage-associated molecular patterns (DAMPs) seem to correlate with SIRS/sepsis morbidity and mortality. Of the known DAMPs, those of mitochondrial (mt) origin have been of particular interest, since their DNA (mtDNA) and formyl peptides (mtFPs) resemble bacterial DNA and peptides, and hence, when released, may be recognized as "danger signals." Critical Issues: mtDAMPs released after tissue injury trigger immune responses similar to those induced by pathogens. Thus, they can result in systemic inflammation and organ damage, similar to that observed in SIRS/sepsis. We will discuss recent findings on the roles of mtDAMPs, particularly regarding the less recognized mtFPs, in the activation of inflammatory responses and development of SIRS/sepsis. Future Directions: There are no established methods to predict the course of SIRS/sepsis, but clinical studies reveal that plasma levels of mtDAMPs may correlate with the outcome of the disease. We propose that non-pathogen-initiated, mtDAMPs-induced SIRS/sepsis events need further studies aimed at early clinical recognition and better treatment of this disease.

Urantide Improves Cardiac Function, Modulates Systemic Cytokine Response, and Increases Survival in A Murine Model of Endotoxic Shock

INTRODUCTION

Urotensin II is a potent vasoactive peptide activating the the G protein-coupled urotensin II receptor UT, and is involved in systemic inflammation and cardiovascular functions. The aim of our work was to study the impact of the UT antagonist urantide on survival, systemic inflammation, and cardiac function during endotoxic shock.

METHODS

C57Bl/6 mice were intraperitoneally injected with lipopolysaccharide (LPS) and then randomized to be injected either by urantide or NaCl 0.9% 3, 6, and 9 h (H3, H6, H9) after LPS. The effect of urantide on the survival rate, the levels of cytokines in plasma at H6, H9, H12, the expression level of nuclear factor-kappa B (NF-κB-p65) in liver and kidney (at H12), and the cardiac function by trans-thoracic echocardiography from H0 to H9 was evaluated.

RESULTS

Urantide treatment improved survival (88.9% vs. 30% on day 6, P < 0.05). This was associated with changes in cytokine expression: a decrease in IL-6 (2,485 [2,280-2,751] pg/mL vs. 3,330 [3,119-3,680] pg/mL, P < 0.01) at H6, in IL-3 (1.0 [0.40-2.0] pg/mL vs. 5.8 [3.0-7.7] pg/mL, P < 0.01), and IL-1β (651 [491-1,135] pg/mL vs. 1,601 [906-3,010] pg/mL, P < 0.05) at H12 after LPS administration. Urantide decreased the proportion of cytosolic NF-κB-p65 in liver (1.3 [0.9-1.9] vs. 3.2 [2.3-4], P < 0.01) and kidney (0.3 [0.3-0.4] vs. 0.6 [0.5-1.1], P < 0.01). Urantide improved cardiac function (left ventricular fractional shortening: 24.8 [21.5-38.9] vs. 12.0 [8.7-17.6] %, P < 0.01 and cardiac output: 30.3 [25.9-39.8] vs. 15.1 [13.0-16.9] mL/min, P < 0.0001).

CONCLUSION

These results show a beneficial curative role of UT antagonism on cytokine response (especially IL-3), cardiac dysfunction, and survival during endotoxic shock in mice, highlighting a potential new therapeutic target for septic patients.

Pgc-1α Promotes Phosphorylation, Inflammation, and Apoptosis in H9c2 Cells During the Early Stage of Lipopolysaccharide Induction

Cardiac dysfunction in severe sepsis is associated with increased mortality. However, the molecular mechanisms underlying septic heart dysfunction remain unclear. Expression of peroxisome proliferator-activated receptor-γ coactivator 1α (Pgc-1α), concentrations of inflammatory factors, and activation of the nuclear factor kappa-B (NF-κB) signaling pathway were examined in H9c2 cells after a 24-h lipopolysaccharide (LPS) stimulation period using qPCR, enzyme-linked immunosorbent assays (ELISAs), and western blots (WBs), respectively. Pgc-1α was overexpressed and suppressed in cells using a lentivirus vector and siRNA, respectively. The effects of Pgc-1α dysfunction on the release of inflammatory factors and apoptosis were analyzed. Pgc-1α expression was increased after LPS induction for 0.5 h and returned to the pre-induction level at 2 h. Levels of IL-1β, IL-6, and TNF-α increase after LPS induction for 0.5 h and accumulated in the culture supernatants over time. The WBs revealed the highest Pgc-1α and phospho (p)-p65 protein levels after LPS induction for 0.5 h, followed by a decrease; moreover, the cleaved-caspase-3 level increased after LPS induction for 0.5 h and increased gradually thereafter. A functional analysis of Pgc-1α revealed that overexpression of this protein enhanced LPS-induced inflammatory factors and p-p65 levels and inhibited apoptosis during the early stage after LPS induction (0.5 and 4 h). In contrast, the inhibition of Pgc-1α expression inhibited the LPS expression-associated increases in inflammatory factors and p-p65 and promoted apoptosis. Pgc-1α promoted LPS-induced p65 phosphorylation and inflammatory factor release while inhibiting apoptosis.

SN50 attenuates alveolar hypercoagulation and fibrinolysis inhibition in acute respiratory distress syndrome mice through inhibiting NF-κB p65 translocation

Background

It has been confirmed that NF-κB p65 signaling pathway is involved in the regulation of alveolar hypercoagulation and fibrinolysis inhibition in acute respiratory distress syndrome (ARDS). Whether SN50, a NF-κB cell permeable inhibitor, could attenuate alveolar hypercoagulation and fibrinolysis inhibition in ARDS remains to be elucidated.

Purpose

We explored the efficacy and potential mechanism of SN50 on alveolar hypercoagulation and fibrinolysis inhibition in ARDS in mice.

Materials and methods

Mouse ARDS was made by 50 μl of lipopolysaccharide (LPS) (4 mg/ml) inhalation. Male BALB/c mice were intraperitoneally injected with different does of SN50 1 h before LPS inhalation. Lung tissues were collected for hematoxylin-eosin (HE) staining, wet/dry ratio. Pulmonary expressions of tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1), collagen III, as well as phosphorylated p65 (p-p65), p65 in nucleus (p’-p65), IκBα and IKKα/β were measured. Bronchoalveolar lavage fluid (BALF) was gathered to test the concentrations of TF, PAI-1, activated protein C (APC) and thrombinantithrombin complex (TAT). DNA binding activity of NF-κB p65 was also determined.

Results

After LPS stimulation, pulmonary edema and exudation and alveolar collapse occured. LPS also stimulated higher expressions of TF and PAI-1 in lung tissues, and higher secretions of TF, PAI-1, TAT and low level of APC in BALF. Pulmonary collagen III expression was obviously enhanced after LPS inhalation. At same time, NF-κB signaling pathway was activated with LPS injury, shown by higher expressions of p-p65, p’-p65, p-IKKα/β, p-Iκα in pulmonary tissue and higher level p65 DNA binding activity. SN50 dose-dependently inhibited TF, PAI-1 and collagen IIIexpressions, and decreased TF, PAI-1, TAT but increased APC in BALF. SN50 treatment attenuated pulmonary edema, exudation and reduced lung tissue damage as well. SN50 application significantly reduced p’-p65 expression and weakened p65 DNA binding activity, but expressions of p-p65, p-IKKα/β, p-Iκα in cytoplasm of pulmonary tissue were not affected.

Conclusions

SN 50 attenuates alveolar hypercoagulation and fibrinolysis inhibition in ARDS via inhibition of NF-κB p65 translocation. Our data demonstrates that NF-κB p65 pathway is a viable new therapeutic target for ARDS treatment.

CTRP1 prevents sepsis-induced cardiomyopathy via Sirt1-dependent pathways

C1q/tumor necrosis factor-related protein 1 (CTRP1) has recently been identified as a key regulator of cardio-metabolic diseases. It has been reported that CTRP1 could inhibit the hypertrophic response in mice. However, the effect of CTRP1 on sepsis-induced cardiomyopathy remains completely unknown. Cardiomyocyte-specific CTRP1 overexpression was achieved using an adeno associated virus system in mice. CTRP1 deficiency mice were also subjected to lipopolysaccharide (LPS) injection. We found that CTRP1 overexpression improved survival rate and cardiac function, and suppressed myocardial inflammation, oxidative damage and apoptosis without affecting metabolic disturbance in LPS-treated mice. CTRP1 depletion further decreased survival rate and cardiac function, and promoting myocardial inflammation, oxidative damage and apoptosis in sepsis mice. In addition, we showed that CTRP1 provided protection against LPS-induced cell injury in vitro. CTRP1 activated sirtuin 1 (Sirt1) signaling pathway, and Sirt1 inhibition or deficiency blocked CTRP1-mediated cardioprotective effects in vivo and in vitro. More importantly, our study found that recombinant human globular domain of CTRP1 infusion was also capable of blocking sepsis-induced cardiomyopathy in mice. In conclusion, CTRP1 improved survival rate and attenuated LPS-induced cardiac injury via activating Sirt1 signaling pathway.

Evidence linking exposure of fish primary macrophages to antibiotics activates the NF-kB pathway

Low doses of antibiotics are ubiquitous in the marine environment and may exert negative effects on non-target aquatic organisms. Using primary macrophages of common carp, we investigated the mechanisms of action following exposure to several common antibiotics; cefotaxime, enrofloxacin, tetracycline, sulfamonomethoxine, and their mixtures, and explored the immunomodulatory effects associated with the nuclear factor-κB (NF-κB) signaling pathway. A KEGG pathway analysis was conducted using the sixty-six differentially expressed genes found in all treatments, and showed that exposure to 100 μg/L of antibiotics could affect regulation of the NF-κB signaling pathway, suggesting that activation of NF-κB is a common response in all four classes of antibiotics. In addition, the four antibiotics induced nf-κb and NF-κB-associated cytokines expression, as verified by qPCR, however, these induction responses by four antibiotics were minor when compared to the same concentration of LPS treatment (100 μg/L). Antagonists of NF-κB blocked many of the immune effects of the antibiotics, providing evidence that NF-κB pathways mediate the actions of all four antibiotics. Moreover, exposure to environmentally relevant, low levels (0.01-100 μg/L) of antibiotics induced a NF-κB-mediated immune response, including endogenous generation of ROS, activity of antioxidant enzymes, as well as expression of cytokine and apoptosis. Moreover, exposure to mixtures of antibiotics presented greater effects on most tested immunological parameters than exposure to a single antibiotic, suggesting additive effects from multiple antibiotics in the environment. This study demonstrates that exposure of fish primary macrophages to low doses of antibiotics activates the NF-kB pathway.

Protective effect of febuxostat in sepsis-induced liver and kidney injuries after cecal ligation and puncture with the impact of xanthine oxidase, interleukin 1β, and c-Jun N-terminal kinases

Sepsis is one of the most common causes of death among hospitalized patients. Activity of xanthine oxidase (XO), a reactive oxygen species-producing enzyme, is known to be elevated in septic patients. Our aim was to investigate the possible protective role of XO inhibitor, febuxostat (FEB), in a rat model of sepsis-induced liver and kidney injures. Adult male albino rats were divided into four groups (n = 12 each): sham control, sham + FEB, cecal ligation and puncture (CLP), and CLP + FEB groups. FEB (10 mg/kg per os (p.o.)) was given once daily for 2 days and 30 min prior to laparotomy with CLP. CLP was associated with a high mortality rate accompanied by significant liver and kidney injuries indicated by elevated serum alanine aminotransferase, aspartate aminotransferase, urea, and creatinine levels and confirmed by histopathological tissue injury. Moreover, there was an increase in neutrophil gelatinase-associated lipocalin, uric acid, malondialdehyde, and nitric oxide levels and with decreased superoxide dismutase activity and total antioxidant capacity. In addition, CLP caused increased expression of the inflammatory markers tumor necrosis factor alpha, interleukin 1beta protein levels, and nuclear factor kappa B immunoexpression. Finally, CLP operated rats exhibited an upregulation in the apoptotic mediators, caspase 3, and P-C-Jun N-terminal kinases (JNK) proteins. FEB treatment of CLP rats caused a significant improvement and normalization in all measured parameters. Moreover, FEB amerliorates degenerative histopathological changes and improves the overall survival rate. In conclusion, FEB exhibited a protective effect in sepsis-induced liver and kidney injuries most probably through its anti-inflammatory, antioxidant, and antiapoptotic properties and attenuating JNK signaling pathway secondary to its XO enzyme inhibitory activity.

Honokiol Attenuates Sepsis-Associated Acute Kidney Injury via the Inhibition of Oxidative Stress and Inflammation

Acute kidney injury (AKI) is one of the most common complications of sepsis, which largely contributes to the high mortality rate of sepsis. Honokiol, a natural polyphenol from the traditional Chinese herb Magnolia officinalis, is known to possess anti-inflammatory and antioxidant activity. Here, the underlying mechanism of honokiol-induced amelioration of sepsis-associated AKI was analyzed. The expression patterns of oxidative stress moleculars and TLRs-mediated inflammation pathway were examined to identify the response of NRK-52E cells incubated with septic rats' serum to honokiol. The levels of iNOS, NO, and myeloperoxidase in NRK-52E cells were increased during sepsis, which could be reversed by honokiol. The production of GSH and SOD as in vivo antioxidant was increased after honokiol treatment. The administration of honokiol significantly inhibited TLR2/4/MyD88 signaling pathway in AKI-induced NRK-52E cells. Furthermore, ZnPPIX, the HO-1 inhibitor, weakened honokiol-mediated morphological amelioration, and the reduced level of TNF-α, IL-1β, and IL-6 in kidneys of rats subjected to CLP. Finally, Honokiol was shown to connect with the Nrf2-Keap1 dimensionally. These findings suggest that honokiol plays its protective role on sepsis-associated AKI against oxidative stress and inflammatory signals.

SM22α (Smooth Muscle 22α) Prevents Aortic Aneurysm Formation by Inhibiting Smooth Muscle Cell Phenotypic Switching Through Suppressing Reactive Oxygen Species/NF-κB (Nuclear Factor-κB)

Objective- Vascular smooth muscle cell phenotypic transition plays a critical role in the formation of abdominal aortic aneurysms (AAAs). SM22α (smooth muscle 22α) has a vital role in maintaining the smooth muscle cell phenotype and is downregulated in AAA. However, whether manipulation of the SM22α gene influences the pathogenesis of AAA is unclear. Here, we investigated whether SM22α prevents AAA formation and explored the underlying mechanisms. Approach and Results- In both human and animal AAA tissues, a smooth muscle cell phenotypic switch was confirmed, as manifested by the downregulation of SM22α and α-SMA (α-smooth muscle actin) proteins. The methylation level of the SM22α gene promoter was dramatically higher in mouse AAA tissues than in control tissues. SM22α knockdown in ApoE^-/- (apolipoprotein E-deficient) mice treated with Ang II (angiotensin II) accelerated the formation of AAAs, as evidenced by a larger maximal aortic diameter and more medial elastin degradation than those found in control mice, whereas SM22α overexpression exerted opposite effects. Similar results were obtained in a calcium chloride-induced mouse AAA model. Mechanistically, SM22α deficiency significantly increased reactive oxygen species production and NF-κB (nuclear factor-κB) activation in AAA tissues, whereas SM22α overexpression produced opposite effects. NF-κB antagonist SN50 or antioxidant N-acetyl-L-cysteine partially abrogated the exacerbating effects of SM22α silencing on AAA formation. Conclusions- SM22α reduction in AAAs because of the SM22α promoter hypermethylation accelerates AAA formation through the reactive oxygen species/NF-κB pathway, and therapeutic approaches to increase SM22α expression are potentially beneficial for preventing AAA formation.

Targeting cell signaling in allergic asthma

Asthma is chronic inflammation of the airways characterized by airway hyper-responsiveness, wheezing, cough, and dyspnea. Asthma affects >350 million people worldwide. The Th2 immune response is a major contributor to the pathophysiology of asthma. Targeted therapy modulating cell signaling pathways can be a powerful strategy to design new drugs to treat asthma. The potential molecular pathways that can be targeted include IL-4-IL-13-JAK-STAT-MAP kinases, adiponectin-iNOS-NF-κB, PGD2-CRTH2, IFNs-RIG, Wnt/β-catenin-FAM13A, FOXC1-miR-PI3K/AKT, JNK-Gal-7, Nrf2-ROS, Foxp3-RORγt, CysLTR, AMP, Fas-FasL, PTHrP/PPARγ, PAI-1, FcɛRI-LAT-SLP-76, Tim-3-Gal-9, TLRs-MyD88, PAR2, and Keap1/Nrf2/ARE. Therapeutic drugs can be designed to target one or more of these pathways to treat asthma.

Recombinant CC16 regulates inflammation, oxidative stress, apoptosis and autophagy via the inhibition of the p38MAPK signaling pathway in the brain of neonatal rats with sepsis

Sepsis has a high in clinic neonatal mortality. Moreover, a considerable number of children's brains remain affected even after the treatment of sepsis and it often leaves sequelae. Therefore, early intervention for sepsis is of considerable significance. Recent studies have shown that Club cell protein (CC16) is closely related to the p38 mitogen-activated protein kinase (MAPK) signaling pathway, which can regulate inflammation, oxidative stress, apoptosis, and autophagy during sepsis. Thus, we analyzed the neuroprotective effect of recombinant CC16 (rCC16) in a neonatal sepsis rat model. For the first time, we found that the p38MAPK signaling pathway was activated in neonatal brain tissue of rats with sepsis, and the CC16 levels decreased significantly. Secondly, after the rCC16 interference, the occurrence of inflammation, oxidative stress and apoptosis were subsequently reversed, and autophagy was further stimulated. Finally, through further intervention using the p38MAPK signaling pathway inhibitor, SB203580, or its agonist, anisomycin, we confirmed that rCC16 reduced rat mortality and improve general conditions. Simultaneously, it had also neuroprotective effect. Its mechanism could be related to oxidative stress, inflammation, and apoptosis reduced and autophagy activated by rCC16 inhibiting the p38MAPK signaling pathway. Taken together, these findings provide insight into the pathogenesis, prevention, and treatment of sepsis via the activity of rCC16.

p38 MAPK activity is associated with the histological degree of interstitial fibrosis in IgA nephropathy patients

Activation of p38 mitogen-activated protein kinase (MAPK) is associated with tissue fibrosis, and inhibition of p38 MAPK can attenuate the progression of fibrosis. We aimed to investigate whether p38 MAPK activity in kidney tissue confirmed by immunohistochemical staining is associated with renal tubulointerstitial fibrosis in chronic kidney disease patients with IgA nephropathy. We collected kidney biopsy specimens from 341 IgA nephropathy patients and 15 control patients to identify the clinical and histopathological factors associated with kidney tubulointerstitial fibrosis and to find an association between kidney phosphorylated p38 immunoactivity and pathological grading. In addition, we aimed to investigate whether the anti-fibrotic effect of p38 MAPK inhibition can be identified by assessing the immunostaining intensity of phosphorylated p38 in kidney tissue. A renal tubulointerstitial fibrosis model was introduced using 7-week-old C57BL/6 mice subjected to unilateral ureteral obstruction (UUO). The p38 MAPK inhibitor SB-731445 was injected intraperitoneally every day for 7 days, and changes in renal fibrosis-associated markers were investigated. Assessment of kidney biopsy specimens from IgA nephropathy patients revealed that the degree of interstitial fibrosis was significantly associated with the tissue immunoactivity of phosphorylated p38. High-grade interstitial fibrosis was associated with a low glomerular filtration rate, high proteinuria, and high-grade histopathological changes, including tubular atrophy, interstitial inflammation, and glomerular sclerosis. In a mouse UUO model, renal protein expression of COL1 and phosphorylated p38 were significantly increased, and the protein expression of COL1 and phosphorylated p38 decreased in mice administered 10 mg/kg/day p38 MAPK inhibitor. We found that kidney interstitial fibrosis is associated with increased immunoactivity of phosphorylated p38 in a UUO mouse model and in human IgA nephropathy patients and that the anti-fibrotic effect of p38 MAPK inhibition can be confirmed using immunohistochemical staining for phosphorylated p38 in kidney tissue.

Selenium influences mmu-miR-155 to inhibit inflammation inStaphylococcus aureus-induced mastitis in mice

Mastitis, a major disease affecting dairy cows, is most commonly caused byStaphylococcus aureus(S. aureus).

Eosinophils attenuate arthritis by inducing M2 macrophage polarization via inhibiting the IκB/P38 MAPK signaling pathway

Rheumatoid arthritis (RA) represents a type of autoimmune disease that mainly affect the joints due to persistent synovitis. Eosinophils were Th2 effector cells that have been shown to have anti-inflammatory role recently. In this study, we aimed to investigate the effects of eosinophils transfer on arthritis and underlying mechanisms. DBA/1 mice were induced with collagen-induced arthritis (CIA) and treated with purified eosinophils at different time points. We showed that eosinophils transfer attenuated arthritis in CIA mice. Meanwhile, TNF-α, IL-6, IL-12 and iNOS levels were decreased whereas TGF-β, IL-10, IL-13 and Arg1 levels were increased after eosinophil transfer. In vitro stimulation of bone marrow-derived macrophage (BMDM) with LPS and IFN-γ induced high expression of CD68, iNOS, TNF-α, IL-6, and IL-12, while treatment with eosinophils downregulated their expression levels. Furthermore, high levels of p-IκB and p-P38 expression in BMDM induced by LPS and IFN-γ could be suppressed by eosinophil treatment, and a P38 or IκB inhibitor accelerated the effect of eosinophils on macrophage polarization. Our results demonstrate that eosinophils exert anti-inflammatory effects in arthritis by inducing M2 macrophage polarization via inhibiting the IκB/P38 MAPK signaling pathway.

Protection by mTOR Inhibition on Zymosan-Induced Systemic Inflammatory Response and Oxidative/Nitrosative Stress: Contribution of mTOR/MEK1/ERK1/2/IKKβ/IκB-α/NF-κB Signalling Pathway

Mammalian target of rapamycin (mTOR), a serine/threonine kinase regulate variety of cellular functions including cell growth, differentiation, cell survival, metabolism, and stress response, is now appreciated to be a central regulator of immune responses. Because mTOR inhibitors enhanced the anti-inflammatory activities of regulatory T cells and decreased the production of proinflammatory cytokines by macrophages, mTOR has been a pharmacological target for inflammatory diseases. In this study, we examined the role of mTOR in the production of proinflammatory and vasodilator mediators in zymosan-induced non-septic shock model in rats. To elucidate the mechanism by which mTOR contributes to non-septic shock, we have examined the activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system caused by mTOR/mitogen-activated protein kinase kinase (MEK1)/extracellular signal-regulated kinase (ERK1/2)/inhibitor κB kinase (IKKβ)/inhibitor of κB (IκB-α)/nuclear factor-κB (NF-κB) signalling pathway activation. After 1 h of zymosan (500 mg/kg, i.p.) administration to rats, mean arterial blood pressure (MAP) was decreased and heart rate (HR) was increased. These changes were associated with increased expression and/or activities of ribosomal protein S6, MEK1, ERK1/2, IKKβ, IκB-α and NF-κB p65, and NADPH oxidase system activity in cardiovascular and renal tissues. Rapamycin (1 mg/kg, i.p.), a selective mTOR inhibitor, reversed these zymosan-induced changes in these tissues. These observations suggest that activation of mTOR/MEK1/ERK1/2/IKKβ/IκB-α/NF-κB signalling pathway with proinflammatory and vasodilator mediator formation and NADPH oxidase system activity contributes to systemic inflammation in zymosan-induced non-septic shock. Thus, mTOR may be an optimal target for the treatment of the diseases characterized by the severe systemic inflammatory response.

Curcumin attenuates high glucose-induced inflammatory injury through the reactive oxygen species-phosphoinositide 3-kinase/protein kinase B-nuclear factor-κB signaling pathway in rat thoracic aorta endothelial cells

AIMS/INTRODUCTION

Endothelial cell inflammatory injury is likely required for barrier dysfunction under hyperglycemic conditions. Curcumin (CUR) is well known for its anti-inflammatory effect. However, there have been few reports about the anti-inflammatory effect of CUR induced by high glucose in endothelial cells. The aim of the present study was to investigate the inflammatory effect of high glucose and the anti-inflammatory effect of CUR induced by high glucose in rat thoracic aorta endothelial cells (TAECs).

MATERIALS AND METHODS

Well characterized TAECs were established and cell viability was assayed by the cell counting kit-8 method, messenger ribonucleic acid and protein expression were identified by real-time polymerase chain reaction, western blot or enzyme-linked immunosorbent assay, respectively. The production of reactive oxygen species was observed by a fluorescence microscope.

RESULTS

High glucose (30 mmol/L) significantly decreased the cell viability of TAECs after being co-cultivated for 12 h and showed a time-dependent manner, and increased interleukin (IL)-1β, IL-6 and tumor necrosis factor-α secretion in TAECs. The injury effect of high glucose was involved in the reactive oxygen species-phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)-nuclear factor (NF)-κB signaling pathway. Anti-oxidant N-acetylcysteine, PI3K and NF-κB-specific pathway inhibitors can abolish the secretion of these inflammatory factors; pretreatment with anti-oxidant N-acetylcysteine significantly decreased PI3K expression, the level of phosphorylated AKT and nuclear NF-κB; pretreatment of LY294002 can significantly decrease the NF-κB level in nuclei. After treatment with CUR for 12 h, IL-1β, IL-6 and tumor necrosis factor-α secretion were markedly decreased, and PI3K expression, the phosphorylation of AKT and nuclear NF-κB level were also decreased.

CONCLUSION

Curcumin attenuates high glucose-induced inflammatory injury through the reactive oxygen species-PI3K/AKT-NF-κB signaling pathway in rat thoracic aorta endothelial cells.

Effect of ozone oxidative preconditioning on inflammation and oxidative stress injury in rat model of renal transplantation

PURPOSE

To investigate the effect of ozone oxidative preconditioning (OzoneOP) on inflammation and oxidative stress injury in rat model of renal transplantation.

METHODS

Thirty six male Sprague Dawley (SD) rats were randomly divided into three groups. Sham group: rats were treated with opening and closing abdomen. Kidney transplantation group (KT group): SD rat received the donor's left kidney derived from another SD rat. Ozone oxidative preconditioning and kidney transplantation (OOP+KT group): donor SD rats received OzoneOP treatments by transrectal insufflations before kidney transplantation. After transplantation, parameters of renal function of recipients were determined. Morphology and pathological changes of renal allograft were examined. Expression of NF-κBp65, HMGB-1 were also determined by Western-blot.

RESULTS

Compared to KT group, the morphology and pathological damages of renal allograft were less serious in OOP+KT group. Meanwhile, levels of SOD and GSH-Px of renal allograft in OOP+KT group were higher than those in KT group respectively. Western-blot showed that the expressions of NF-κBp65 and HMGB-1 in OOP+KT group were obviously less than those in KT group.

CONCLUSION

Ozone oxidative preconditioning could attenuate the inflammatory reaction and oxidative stress injury in renal allograft, which might be related with the enhancement of anti-oxidative system and suppression of inflammatory reaction.

2,3,5,4'‑Tetrahydroxystilbene‑2‑O‑β‑D‑glucoside inhibits septic serum‑induced inflammatory injury via interfering with the ROS‑MAPK‑NF‑κB signaling pathway in pulmonary aortic endothelial cells

Sepsis is characterized by injury to the microvasculature and the microvascular endothelial cells, leading to barrier dysfunction. However, the specific role of injury in septic endothelial barrier dysfunction remains to be elucidated. In the present study, it was hypothesized that endothelial cell inflammatory injury is likely required for barrier dysfunction under septic conditions in vitro. 2,3,5,4'‑Tetrahydroxystilbene‑2‑O‑β‑D‑glucoside (TSG), a compound extracted from Chinese herbs, is able to inhibit the inflammatory injury of septic‑serum in endothelial cells. In the present study, cell viability was assayed by CCK‑8 method; mRNA and protein expression was identified by RT‑qPCR, western blot or Elisa, respectively and the production of reactive oxygen species was observed by a fluorescence microscope. The present study indicated that septic serum significantly decreased the cell viability of pulmonary aortic endothelial cells (PAECs) following co‑cultivation for 6 h, which occurred in a time‑dependent manner. TSG notably increased the viability of PAECs in a time‑ and concentration‑dependent manner. Further investigations revealed that septic serum increased the secretion of interleukin (IL)‑1β, IL‑6 and C‑reactive protein in PAECs, whereas pretreatment with TSG significantly decreased the secretion of these inflammatory factors. These data indicated that septic serum increased inflammatory injury to the PAECs, and TSG decreased this injury via the reactive oxygen species‑mitogen‑activated protein kinase‑nuclear factor‑κB signaling pathway.

Mitogen-activated protein kinase pathways in sepsis treatment

Sepsis is a characteristic set of systemic reactions to overwhelming infection that remains a major cause of death in critically ill patients. Endotoxins or lipopolysaccharides from gram-negative bacteria play a major role in the pathogenesis by inducing an over-production of inflammatory cytokines, which usually triggers beneficial inflammatory responses but causes tissue injury and lethal multiple organ failure in excessive amounts. The production of inflammatory cytokines depends on the activation of many intracellular signaling pathways, including nuclear factor-κB (NF-κB) pathway and three mitogen-activated protein kinase (MAPK) pathways. This review of important MAPK pathways underscores the essential role of MKP-1 in the negative control of sepsis. Herein is a summary of the roles of MAPK pathways in the production of inflammatory cytokines and the possibility of targeting these pathways for the treatment of sepsis.

Why Antibiotic Treatment Is Not Enough for Sepsis Resolution: an Evaluation in an Experimental Animal Model

Sepsis remains a major health problem at the levels of mortality, morbidity, and economic burden to the health care system, a condition that is aggravated by the development of secondary conditions such as septic shock and multiple-organ failure. Our current understanding of the etiology of human sepsis has advanced, at least in part, due to the use of experimental animal models, particularly the model of cecum ligation and puncture (CLP). Antibiotic treatment has been commonly used in this model to closely mirror the treatment of human septic patients. However, whether their use may obscure the elucidation of the cellular and molecular mechanisms involved in the septic response is questionable. The objective of the present study was to determine the effect of antibiotic treatment in the outcome of a fulminant model of CLP. Various dosing strategies were used for the administration of imipenem, which has broad-spectrum coverage of enteric bacteria. No statistically significant differences in the survival of mice were observed between the different antibiotic dosing strategies and no treatment, suggesting that live bacteria may not be the only factor inducing septic shock. To further investigate this hypothesis, mice were challenged with sterilized or unsterilized cecal contents. We found that exposure of mice to sterilized cecal contents also resulted in a high mortality rate. Therefore, it is possible that bacterial debris, apart from bacterial proliferation, triggers a septic response and contributes to mortality in this model, suggesting that additional factors are involved in the development of septic shock.

Celecoxib Enhances the Efficacy of Low-Dose Antibiotic Treatment against Polymicrobial Sepsis in Mice and Clinical Isolates of ESKAPE Pathogens

Treatment of multidrug resistant bacterial infections has been a great challenge globally. Previous studies including our study have highlighted the use of celecoxib, a non-steroidal anti-inflammatory drug in combination with antibiotic has decreased the minimal inhibitory concentration to limit Staphylococcus aureus infection. However, the efficacy of this combinatorial treatment against various pathogenic bacteria is not determined. Therefore, we have evaluated the potential use of celecoxib in combination with low doses of antibiotic in limiting Gram-positive and Gram-negative bacteria in vivo in murine polymicrobial sepsis developed by cecum ligation and puncture (CLP) method and against clinically isolated human ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). The in vivo results clearly demonstrated a significant reduction in the bacterial load in different organs and in the inflammatory markers such as COX-2 and NF-κB via activation of SIRT1 in mice treated with imipenem, a choice of antibiotic for polymicrobial sepsis treatment. Combinatorial treatment of ampicillin and celecoxib was effective on clinical isolates of ESKAPE pathogens, 45% of tested clinical isolates showed more than 50% reduction in the colony forming units when compared to ampicillin alone. In conclusion, this non-traditional treatment strategy might be effective in clinic to reduce the dose of antibiotic to treat drug-resistant bacterial infections.

The correlation between inflammatory injury induced by LPS and RAS in EpH4-Ev cells

Renin-angiotensin system (RAS) plays an important role of regulating inflammatory injury. However, it is not clear about the correlation between renin-angiotensin system (RAS) and inflammation induced by LPS in mammary gland cells. So immunofluorescence was performed to verify the ACE2 expression in mammary gland cells. MTT assay was performed to detect cell viability. ELISA was performed to detect cytokines in cell supernatant. Western Blot was performed to analyze RAS levels and ACE2 level change was observed by immunofluorescence. The TLR4 level and p65 phosphorylation were detected by Western Blot. The ACE2 protein intensively located on the cell membrane. According to the results of MTT assay and TNF-α level, the injury was evidently induced by high concentration LPS after 9h. The TNF-α, IL-6, IL-8, ACE, AT1R and AngII had an increasing expression with the rise of cell injury. In contrast, the MasR, Ang1-7 and ACE2 had a declining expression with the increase of cell injury degree. The TLR4 level and p65 phosphorylation in high concentration LPS group was significantly higher than that of control group. These results suggest that a valid inflammatory injury was induced after the cells were treated by high concentration of LPS for 9h. Meanwhile, the ACE/AngII/AT1R axis was activated and the ACE2/Ang1-7/MasR axis was depressed.

Protective Effects of Nobiletin Against Endotoxic Shock in Mice Through Inhibiting TNF-α, IL-6, and HMGB1 and Regulating NF-κB Pathway

Nobiletin (NOB), the major bioactive component of polymethoxyflavones in citrus fruits, has been reported possessing significant biological properties. The purpose of the present study was to investigate the protective role of NOB on lipopolysaccharide (LPS)-induced endotoxic shock in mice. We found pretreatment with NOB increases the survival rate of mice after endotoxin injection. The present study clearly demonstrates that pretreatment with NOB decreases the production of early pro-inflammatory cytokines TNF-α, IL-6, and late-phase mediator HMGB1 in serum and tissues of kidney, lung, and liver. The histopathological study indicates that NOB administration significantly attenuate tissues injury induced by LPS. Moreover, NOB suppresses the activity of nuclear factor-kappa B (NF-κB). These results suggest that NOB protects mice against LPS-induced endotoxic shock through inhibiting the production of TNF-α, IL-6, and HMGB1 and the activation of NF-κB, which elucidate that NOB may be a promising drug candidate for the treatment of septic shock.

Cardiopulmonary Bypass Down-Regulates NOD Signaling and Inflammatory Response in Children with Congenital Heart Disease

In the present study, we aimed to examine the impact of cardiopulmonary bypass (CPB) on expression and function of NOD1 and NOD2 in children with congenital heart disease (CHD), in an attempt to clarify whether NOD1 and NOD2 signaling is involved in the modulation of host innate immunity against postoperative infection in pediatric CHD patients. Peripheral blood samples were collected from pediatric CHD patients at five different time points: before CPB, immediately after CPB, and 1, 3, and 7 days after CPB. Real-time PCR, Western blot, and ELISA were performed to measure the expression of NOD1 and NOD2, their downstream signaling pathways, and inflammatory cytokines at various time points. Proinflammatory cytokine IL-6 and TNF-α levels in response to stimulation with either the NOD1 agonist Tri-DAP or the NOD2 agonist MDP were significantly reduced after CPB compared with those before CPB, which is consistent with a suppressed inflammatory response postoperatively. The expression of phosphorylated RIP2 and activation of the downstream signaling pathways NF-κB p65 and MAPK p38 upon Tri-DAP or MDP stimulation in PBMCs were substantially inhibited after CPB. The mRNA level of NOD1 and protein levels of NOD1 and NOD2 were also markedly decreased after CPB. Our results demonstrated that NOD-mediated signaling pathways were substantially inhibited after CPB, which correlates with the suppressed inflammatory response and may account, at least in part, for the increased risk of postoperative infection in pediatric CHD patients.

Treatment With Human Wharton's Jelly-Derived Mesenchymal Stem Cells Attenuates Sepsis-Induced Kidney Injury, Liver Injury, and Endothelial Dysfunction

: The pathophysiology of sepsis involves complex cytokine and inflammatory mediator networks. Downregulation of endothelial nitric oxide synthase contributes to sepsis-induced endothelial dysfunction. Human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) are known to reduce expression of proinflammatory cytokines and markers of apoptosis. We hypothesized that treatment with WJ-MSCs would protect renal, hepatic, and endothelial function in a cecal ligation and puncture (CLP) model of sepsis in rats. Rats were randomly divided into three groups: sham-operated rats; rats submitted to CLP and left untreated; and rats submitted to CLP and intraperitoneally injected, 6 hours later, with 1 × 10(6) WJ-MSCs. The glomerular filtration rate (GFR) was measured at 6 and 24 hours after CLP or sham surgery. All other studies were conducted at 24 hours after CLP or sham surgery. By 6 hours, GFR had decreased in the CLP rats. At 24 hours, Klotho renal expression significantly decreased. Treatment with WJ-MSCs improved the GFR; improved tubular function; decreased the CD68-positive cell count; decreased the fractional interstitial area; decreased expression of nuclear factor κB and of cytokines; increased expression of eNOS, vascular endothelial growth factor, and Klotho; attenuated renal apoptosis; ameliorated hepatic function; increased glycogen deposition in the liver; and improved survival. Sepsis-induced acute kidney injury is a state of Klotho deficiency, which WJ-MSCs can attenuate. Klotho protein expression was higher in WJ-MSCs than in human adipose-derived MSCs. Because WJ-MSCs preserve renal and hepatic function, they might play a protective role in sepsis.

SIGNIFICANCE

Sepsis is the leading cause of death in intensive care units. Although many different treatments for sepsis have been tested, sepsis-related mortality rates remain high. It was hypothesized in this study that treatment with human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) would protect renal, hepatic, and endothelial function in a model of sepsis in rats. Treatment with WJ-MSCs improved the glomerular filtration rate, improved tubular function, decreased expression of nuclear factor κB and of cytokines, increased expression of eNOS and of Klotho, attenuated renal apoptosis, and improved survival. Sepsis-induced acute kidney injury is a state of Klotho deficiency, which WJ-MSCs can attenuate.

Maternal inflammation activated ROS-p38 MAPK predisposes offspring to heart damages caused by isoproterenol via augmenting ROS generation

Maternal inflammation contributes to the increased incidence of adult cardiovascular disease. The current study investigated the susceptibility of cardiac damage responding to isoproterenol (ISO) in adult offspring that underwent maternal inflammation (modeled by pregnant Sprague-Dawley rats with lipopolysaccharides (LPS) challenge). We found that 2 weeks of ISO treatment in adult offspring of LPS-treated mothers led to augmented heart damage, characterized by left-ventricular systolic dysfunction, cardiac hypertrophy and myocardial fibrosis. Mechanistically, prenatal exposure to LPS led to up-regulated expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, antioxidant enzymes, and p38 MAPK activity in left ventricular of adult offspring at resting state. ISO treatment exaggerated ROS generation, p38 MAPK activation but down-regulated reactive oxygen species (ROS) elimination capacity in the left ventricular of offspring from LPS-treated mothers, while antioxidant N-acetyl-L-cysteine (NAC) reversed these changes together with improved cardiac functions. The p38 inhibitor SB202190 alleviated the heart damage only via inhibiting the expression of NADPH oxidases. Collectively, our data demonstrated that prenatal inflammation programs pre-existed ROS activation in the heart tissue, which switches on the early process of oxidative damages on heart rapidly through a ROS-p38 MAPK-NADPH oxidase-ROS positive feedback loop in response to a myocardial hypertrophic challenge in adulthood.

Endothelium-Derived 5-Methoxytryptophan Is a Circulating Anti-Inflammatory Molecule That Blocks Systemic Inflammation

Rationale:

Systemic inflammation has emerged as a key pathophysiological process that induces multiorgan injury and causes serious human diseases. Endothelium is critical in maintaining cellular and inflammatory homeostasis, controlling systemic inflammation, and progression of inflammatory diseases. We postulated that endothelium produces and releases endogenous soluble factors to modulate inflammatory responses and protect against systemic inflammation.

Objective:

To identify endothelial cell–released soluble factors that protect against endothelial barrier dysfunction and systemic inflammation.

Methods and Results:

We found that conditioned medium of endothelial cells inhibited cyclooxgenase-2 and interleukin-6 expression in macrophages stimulated with lipopolysaccharide. Analysis of conditioned medium extracts by liquid chromatography–mass spectrometry showed the presence of 5-methoxytryptophan (5-MTP), but not other related tryptophan metabolites. Furthermore, endothelial cell–derived 5-MTP suppressed lipopolysaccharide-induced inflammatory responses and signaling in macrophages and endotoxemic lung tissues. Lipopolysaccharide suppressed 5-MTP level in endothelial cell-conditioned medium and reduced serum 5-MTP level in the murine sepsis model. Intraperitoneal injection of 5-MTP restored serum 5-MTP accompanied by the inhibition of lipopolysaccharide-induced endothelial leakage and suppression of lipopolysaccharide- or cecal ligation and puncture–mediated proinflammatory mediators overexpression. 5-MTP administration rescued lungs from lipopolysaccharide-induced damages and prevented sepsis-related mortality. Importantly, compared with healthy subjects, serum 5-MTP level in septic patients was decreased by 65%, indicating an important clinical relevance.

Conclusions:

We conclude that 5-MTP belongs to a novel class of endothelium-derived protective molecules that defend against endothelial barrier dysfunction and excessive systemic inflammatory responses.

sn-1,2-diacylglycerols protect against lethal endotoxemia by controlling systemic inflammation

Systemic inflammation has emerged as a key pathophysiological process that induces multiple organ injuries and causes serious human diseases. Despite substantial evidence supporting the role of diacylglycerols (DAG) in modulating chronic inflammation and chronic diseases, the potential mechanisms of its involvement in TLRs-mediated inflammation are still unclear. Here, we show that sn-1,2-diacylglycerols modulate LPS/TLR4-mediated inflammation in vitro and in vivo. ELISA and western blotting experiments indicated that sn-1,2-diacylglycerols suppress LPS-induced responses, including IL-6 and TNF-α production, and COX-2 expression in mouse RAW264.7 macrophages and human endothelial cells, in a dose-dependent manner. Using LPS-induced murine model of systemic inflammation, we show that sn-1,2-diacylglycerols block the cytokine storm, the expression of inflammatory mediators, and LPS-induced septic lung damage and mortality. sn-1,2-diacylglycerols reduce systemic inflammation by inhibiting LPS-induced p38 MAPK- and PI3K/AKT-mediated NF-κB activation in macrophages. These results suggest that exogenous DAG probably acts by blocking p38 MAPK or PI3K/AKT signal transduction, thereby down-regulating NF-κB activation and NF-κB-mediated transcription of genes encoding cytokines and pro-inflammatory oxidative enzymes. Our findings demonstrate that exogenous sn-1,2-diacylglycerol protects mice from LPS-induced lethal endotoxemia by suppressing TLR4-driven inflammatory responses, suggesting that 1,2-diacylglycerols may be used as dietary health supplements for the prevention or therapy of systemic inflammatory diseases.

Emodin alleviates lung injury in rats with sepsis

BACKGROUND

Sepsis has high morbidity and mortality. The aim of this study was to investigate whether emodin, an anthraquinone derived from Chinese herb, exerts protective effects on lung injury in rat model of sepsis.

MATERIALS AND METHODS

Forty-eight male Wistar rats were randomly divided into four groups (n = 12): normal group, sham-operated group, cecal ligation and puncture (CLP) model group, and emodin-treated group. Saline or emodin (25 mg/kg) was injected intraperitoneally 0.5 h before CLP. The rats were sacrificed 48 h after CLP. Lung wet-to-dry weight ratio and pathologic changes in the lung were examined, the contents of malondialdehyde and myeloperoxidase in lung tissue were detected, serum tumor necrosis factor alpha and interleukin 6 levels were measured by enzyme-linked immunosorbent assay, and the phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK) was detected by Western blot analysis.

RESULTS

Compared with control group, CLP group exhibited higher wet-to-dry weight ratio and water content in the lung (P < 0.01), but these indexes were reduced and pathologic changes in the lung were relieved in the emodin-treated group. In addition, lung malondialdehyde and myeloperoxidase contents, serum levels of tumor necrosis factor alpha and interleukin 6, and phosphorylation of p38 MAPK increased in the CLP group but decreased in the emodin-treated group (P < 0.05).

CONCLUSIONS

Emodin exerts protective effects on lung injury in septic rats, which is related to the inhibition of p38 MAPK pathway and the reduction of oxidative stress and inflammation response during sepsis.

Betulin attenuates lung and liver injuries in sepsis

Sepsis is a complex condition with unacceptable mortality. Betulin is a natural extract with multiple bioactivities. This study aims to evaluate the potential effects of betulin on lung and liver injury in sepsis. Cecal ligation and puncture was used to establish the rat model of sepsis. A single dose of 4mg/kg or 8mg/kg betulin was injected intraperitoneally immediately after the model establishment. The survival rate was recorded every 12h for 96h. The organ injury was examined using hematoxylin and eosin staining and serum biochemical test. The levels of proinflammatory cytokines and high mobility group box 1 in the serum were measured using ELISA. Western blotting was used to detect the expression of proteins in NF-κB and MAPK signaling pathways. Betulin treatment significantly improved the survival rate of septic rats, and attenuated lung and liver injury in sepsis, including the reduction of lung wet/dry weight ratio and activities of alanine aminotransferase and aspartate aminotransferase in the serum. In addition, levels of tumor necrosis factor-α, interleukin-1β, interleukin-6 and high mobility group box 1 in the serum were also lowered by betulin treatment. Moreover, sepsis-induced activation of the NF-κB and MAPK signaling pathway was inhibited by betulin as well. Our findings demonstrate the protective effect of betulin in lung and liver injury in sepsis. This protection may be mediated by its anti-inflammatory and NF-κB and MAPK inhibitory effects.

TNFAIP2 Inhibits Early TNFα-Induced NF-x03BA;B Signaling and Decreases Survival in Septic Shock Patients

During septic shock, tumor necrosis factor alpha (TNFα) is an early response gene and induces a plethora of genes and signaling pathways. To identify robust signals in genes reliably upregulated by TNFα, we first measured microarray gene expression in vitro and searched methodologically comparable, publicly available data sets to identify concordant signals. Using tag single-nucleotide polymorphisms in the genes common to all data sets, we identified a genetic variant of the TNFAIP2 gene, rs8126, associated with decreased 28-day survival and increased organ dysfunction in an adult cohort in the Vasopressin and Septic Shock Trial. Similar to this cohort, we found that an association with rs8126 and increased organ dysfunction is replicated in a second cohort of septic shock patients in the St. Paul's Hospital Intensive Care Unit. We found that TNFAIP2 inhibits NF-x03BA;B activity, impacting the downstream cytokine interleukin (IL)-8. The minor G allele of TNFAIP2 rs8126 resulted in greater TNFAIP2 expression, decreased IL-8 production and was associated with decreased survival in patients experiencing septic shock. These data suggest that TNFAIP2 is a novel inhibitor of NF-x03BA;B that acts as an autoinhibitor of the TNFα response during septic shock.

Lysosome and Cytoskeleton Pathways Are Robustly Enriched in the Blood of Septic Patients: A Meta-Analysis of Transcriptomic Data

Background. Sepsis is a leading cause of mortality in intensive care units worldwide. A better understanding of the blood systems response to sepsis should expedite the identification of biomarkers for early diagnosis and therapeutic interventions. Methods. We analyzed microarray studies whose data is available from the GEO repository and which were performed on the whole blood of septic patients and normal controls. Results. We identified 6 cohorts consisting of 450 individuals (sepsis = 323, control = 127) providing genome-wide messenger RNA (mRNA) expression data. Through meta-analysis we found the “Lysosome” and “Cytoskeleton” pathways were upregulated in human sepsis patients relative to controls, in addition to previously known signaling pathways (including MAPK, TLR). The key regulatory genes in the “Lysosome” pathway include lysosomal acid hydrolases (e.g., protease cathepsin A, D) as well as the major (LAMP1, 2) and minor (SORT1, LAPTM4B) membrane proteins. In contrast, pathways related to “Ribosome”, “Spliceosome” and “Cell adhesion molecules” were found to be downregulated, along with known pathways for immune dysfunction. Overall, our study revealed distinct mRNA activation profiles and protein-protein interaction networks in blood of human sepsis. Conclusions. Our findings suggest that aberrant mRNA expression in the lysosome and cytoskeleton pathways may play a pivotal role in the molecular pathobiology of human sepsis.

Effects of honokiol on sepsis-induced acute kidney injury in an experimental model of sepsis in rats

Acute kidney injury (AKI) is a severe complication of sepsis, which largely contributes to the high mortality rate of sepsis. Honokiol, a natural product isolated from Magnolia officinalis (Houpo), has been shown to exhibit anti-inflammatory and antioxidant properties. Here, we investigated the effects of honokiol on sepsis-associated AKI in rats subjected to cecal ligation and puncture (CLP). We found that the administration of honokiol improved the survival of septic rats. Periodic acid-Schiff stain revealed that the morphological changes of kidney tissues in CLP rats were restored after honokiol treatment. Furthermore, honokiol reduced CLP-induced oxidative stress and inflammatory cytokine production. The levels of nitric oxide (NO) and inducible NO synthetase (iNOS) were attenuated by honokiol in septic rats. Finally, honokiol inhibited CLP-induced activation of NF-κB signaling in CLP rats. Our findings suggest that honokiol might be used as a potential therapeutic agent for complications of sepsis, especially for sepsis-induced AKI.

LPS- and LTA-induced expression of IL-6 and TNF-α in neonatal and adult blood: role of MAPKs and NF-κB

As nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) seem to be critical mediators in the inflammatory response, we studied the effects of lipopolysaccharide (LPS) and lipoteichoic acid (LTA) on (a) the activation of NF-κB and MAPKs and (b) the expression of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) with or without the specific inhibitors of these intracellular signal transduction pathways in neonatal cord and adult blood. TNF-α and IL-6 concentrations showed a sharp increase in the supernatants of cord and adult whole blood after stimulation. TNF-α concentrations were significantly higher, whereas IL-6 concentrations were tendentially lower in adult blood after stimulation. Stimulation with LPS or LTA resulted in a significantly decreased activation of p38 MAPK in neonatal compared with adult blood. Although LTA failed to induce additional ERK1/2 phosphorylation, LPS stimulation mediated the moderately increased levels of activated ERK1/2 in neonatal monocytes. The addition of the p38 MAPK inhibitor SB202190 significantly decreased IL-6 and TNF-α production upon LPS or LTA stimulation. Furthermore, the inhibition of ERK1/2 was able to reduce LPS-stimulated TNF-α production in neonatal blood. We conclude that p38 MAPK as well as ERK1/2 phosphorylation is crucially involved in LPS activation and could explain the differences in early cytokine response between neonatal and adult blood.

The "genomic storm" induced by bacterial endotoxin is calmed by a nuclear transport modifier that attenuates localized and systemic inflammation

Lipopolysaccharide (LPS) is a potent microbial virulence factor that can trigger production of proinflammatory mediators involved in the pathogenesis of localized and systemic inflammation. Importantly, the role of nuclear transport of stress responsive transcription factors in this LPS-generated "genomic storm" remains largely undefined. We developed a new nuclear transport modifier (NTM) peptide, cell-penetrating cSN50.1, which targets nuclear transport shuttles importin α5 and importin β1, to analyze its effect in LPS-induced localized (acute lung injury) and systemic (lethal endotoxic shock) murine inflammation models. We analyzed a human genome database to match 46 genes that encode cytokines, chemokines and their receptors with transcription factors whose nuclear transport is known to be modulated by NTM. We then tested the effect of cSN50.1 peptide on proinflammatory gene expression in murine bone marrow-derived macrophages stimulated with LPS. This NTM suppressed a proinflammatory transcriptome of 37 out of 84 genes analyzed, without altering expression of housekeeping genes or being cytotoxic. Consistent with gene expression analysis in primary macrophages, plasma levels of 23 out of 26 LPS-induced proinflammatory cytokines, chemokines, and growth factors were significantly attenuated in a murine model of LPS-induced systemic inflammation (lethal endotoxic shock) while the anti-inflammatory cytokine, interleukin 10, was enhanced. This anti-inflammatory reprogramming of the endotoxin-induced genomic response was accompanied by complete protection against lethal endotoxic shock with prophylactic NTM treatment, and 75% protection when NTM was first administered after LPS exposure. In a murine model of localized lung inflammation caused by direct airway exposure to LPS, expression of cytokines and chemokines in the bronchoalveolar space was suppressed with a concomitant reduction of neutrophil trafficking. Thus, calming the LPS-triggered "genomic storm" by modulating nuclear transport with cSN50.1 peptide attenuates the systemic inflammatory response associated with lethal shock as well as localized lung inflammation.

Calcium-sensing receptor in the T lymphocyte enhanced the apoptosis and cytokine secretion in sepsis

Calcium-sensing receptor (CaSR) is a member of the G protein-coupled receptor superfamily that existed in lymphocytes and promoted cytokine secretion. Lymphocytes are also involved in sepsis. However, the role of CaSR in lymphocytes in sepsis is unclear. In this study, we want to examine whether the CaSR in lymphocytes in sepsis is involved in the cytokine secretions and apoptosis and make clear the relationship between NF-κB and MAPK signal transduction pathways. We investigated the issues mentioned earlier using Western blotting, ELISA, and Flow Cytometry. The sepsis was remodeled by cecal ligation and puncture (CLP). We found that CaSR protein expression increased in the peripheral blood T lymphocytes in CLP rats. The calcimimetic R568 (NPS R568) promoted, whereas the calcilytic NPS 2143 attenuated, signaling pathways proteins P65 (subunit of NF-κB), ERK1/2, and JNK (one subgroup of MAPKs) phosphorylation. However, P-P38 and P-JAKs exhibit no significant changes. Furthermore, the production TNF-α and IL-4 was greater in CLP rats than in normal rats, and NPS R568 promoted secretion of these cytokines. Simultaneously, the apoptotic ratio of T cells in CLP increased, and NPS R 568 exacerbated the apoptosis degree. However, these effects could also be inhibited by U0126 or SP600125 (MAPKs pathway inhibitor) or Bay-11-7082 or (NF-κB pathway inhibitor). From these results, we can conclude that, in the sepsis, CaSR activation promoted T-cell apoptosis and the secretion of pro-inflammatory cytokine TNF-α and anti-inflammatory cytokines IL-4 probably through NF-κB and partial MAPK signal transduction pathways.

Thrombin promotes proliferation of human lung fibroblasts via protease activated receptor-1-dependent and NF-κB-independent pathways

Acute and chronic respiratory diseases are associated with abnormal coagulation regulation and fibrolysis. However, the detailed mechanism by which coagulation regulation and fibrolysis affect the occurrence and development of lung diseases remain to be elucidated. Protease activated receptor-1 (PAR-1), a major high-affinity thrombin receptor, and nuclear factor kappa B (NF-κB), a transcription factor, are involved in cell survival, differentiation, and proliferation. We have investigated the potential mechanism of thrombin-induced fibroblast proliferation and roles of PAR-1 and NF-κB signalling in this process. The effect of thrombin on proliferation of human pulmonary fibroblasts (HPF) was assessed by 5-bromo-2-deoxyuridine (BrdU) incorporation assay. The expression of PAR1 and NF-κB subunit p65 protein was detected by Western blot. Nuclear translocation of p65 was examined by laser scanning confocal microscopy. We show that thrombin significantly increased proliferation of HPF as determined by induction of BrdU-positive incorporation ratio. Induced PAR1 protein expression was also seen in HPF cells treated with thrombin. However, thrombin had no significant effect on expression and translocation of NF-κB p65 in HPF cells. The results indicate that, by increasing protein expression and interacting with PAR1, thrombin promotes HPF proliferation. NF-κB signalling appears to play no role in this process.

Inhibitor of nuclear factor-κB, SN50, attenuates lipopolysaccharide-induced lung injury in an isolated and perfused rat lung model

NF-κB cell permeable inhibitory peptide (SN50) inhibits translocation of nuclear factor-κB (NF-κB) and production of inflammatory cytokines that are implicated in lipopolysaccharide (LPS)-induced lung injury (LPSLI). However, the protective effect of SN50 in LPSLI is unclear. We explored the cellular and molecular mechanisms of SN50 treatment in LPSLI. LPSLI was induced by intratracheal instillation of 10 mg/kg LPS using an isolated and perfused rat lung model. SN50 was administered in the perfusate 15 minutes before LPS was administered. Hemodynamics, lung histologic change, inflammatory responses, and activation of apoptotic pathways were evaluated. After LPSLI, increased pulmonary vascular permeability and lung weight gain was observed. The levels of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, myeloperoxidase, and macrophage inflammatory protein-2 increased in bronchoalveolar lavage fluids. Lung-tissue expression of TNF-α, IL-1β, mitogen-activated protein kinases (MAPKs), caspase-3, p-AKT (serine-threonine kinase, also known as protein kinase B), and plasminogen activator inhibitor-1 (PAI-1) was greater in the LPS group compared with controls. Upregulation and activation of NF-κB was associated with increased lung injury in LPSLI. SN50 attenuated the inflammatory responses, including expression of IL-1β, TNF-α, myeloperoxidase, MAPKs, PAI-1, and NF-κB; downregulation of apoptosis indicated by caspase-3 and p-AKT expression was also observed. In addition, SN50 mitigated the increase in the lung weight, pulmonary vascular permeability, and lung injury. In conclusion, LPSLI is associated with inflammatory responses, apoptosis, and coagulation. NF-κB is an important therapeutic target in the treatment of LPSLI. SN50 inhibits translocation of NF-κB and attenuates LPSLI.