NF-kappa B and rel proteins in innate immunity

The MAB-5/Hox family transcription factor is important for Caenorhabditis elegans innate immune response to Staphylococcus epidermidis infection

Innate immunity functions as a rapid defense against broad classes of pathogenic agents. While the mechanisms of innate immunity in response to antigen exposure are well-studied, how pathogen exposure activates the innate immune responses and the role of genetic variation in immune activity is currently being investigated. Previously, we showed significant survival differences between the N2 and the CB4856 Caenorhabditis elegans isolates in response to Staphylococcus epidermidis infection. One of those differences was expression of the mab-5 Hox family transcription factor, which was induced in N2, but not CB4856, after infection. In this study, we use survival assays and RNA-sequencing to better understand the role of mab-5 in response to S. epidermidis. We found that mab-5 loss-of-function (LOF) mutants were more susceptible to S. epidermidis infection than N2 or mab-5 gain-of-function (GOF) mutants, but not as susceptible as CB4856 animals. We then conducted transcriptome analysis of infected worms and found considerable differences in gene expression profiles when comparing animals with mab-5 LOF to either N2 or mab-5 GOF. N2 and mab-5 GOF animals showed a significant enrichment in expression of immune genes and C-type lectins, whereas mab-5 LOF mutants did not. Overall, gene expression profiling in mab-5 mutants provided insight into MAB-5 regulation of the transcriptomic response of C. elegans to pathogenic bacteria and helps us to understand mechanisms of innate immune activation and the role that transcriptional regulation plays in organismal health.

Serum Selenium and Inflammation in Individuals with Human Immunodeficiency Virus Infection

HIV infection has been linked to selenium deficiency and chronic inflammation. Both selenium deficiency and inflammation have been associated with poor health outcomes among individuals with HIV. However, the role of serum selenium levels in inflammation has not been studied among individuals with HIV. We assessed the relationship of serum selenium levels to C-reactive protein (CRP), a marker of inflammation, in individuals with HIV in Kathmandu, Nepal. In this cross-sectional study, we measured the normal serum CRP and selenium levels of 233 individuals with HIV (109 women and 124 men) using the latex agglutination turbidimetric and atomic absorption methods, respectively. We used multiple linear regression analysis in examining the association of serum selenium levels with CRP adjusting for sociodemographic and clinical parameters, including antiretroviral therapy, CD4+ T cell count, chronic diseases, and body mass index. The geometric means of CRP and selenium levels were 1.43 mg/liter and 9.65 μg/dL, respectively. Overall, serum selenium levels were inversely associated with CRP levels (β for one unit change in log selenium; β = -1.01, p = .06). Mean CRP levels significantly decreased with increasing selenium across selenium tertiles (p for trend = .019). The mean serum CRP levels were 40.8% lower in the highest selenium tertile than in the lowest. Our study suggests that high serum selenium levels may reduce serum CRP levels in individuals with HIV, although a longitudinal study is warranted to establish causality.

Green tea extract improves cyclophosphamide-induced immunosuppression in mouse spleen and enhances the immune activity of RAW 264.7 cells

Cyclophosphamide (CP) is mainly used to treat autoimmune diseases and cancer; however, it damages normal immune cells. Therefore, the effects of chemotherapy on CP are limited. Notably, green tea has been reported to effectively modulate immune function. Here, given the pharmacological properties of green tea, we evaluated the ability of green tea extract (GTE) to restore immunity suppressed by CP in vivo and to activate macrophages in vitro. GTE significantly improved the suppressed immune function, including spleen index and proliferation of spleen T lymphocytes, as revealed by histopathological examination and flow cytometry analysis. Moreover, GTE effectively activated RAW 264.7, as represented by the induction of nitric oxide, reactive oxygen species, and cytokine levels. GTE also increased the phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B in RAW 264.7 cells. In conclusion, GTE ameliorated CP-induced immunosuppression in mice and stimulated immune activity in RAW 264.7 cells, possibly by activating the MAPK signaling pathway. These findings suggest that GTE has the potential to be used as a supplementary agent in chemotherapy for CP.

Repositioning the existing drugs for neuroinflammation: a fusion of computational approach and biological validation to counter the Parkinson's disease progression

Parkinson's disease is caused by the deficiency of striatal dopamine and the accumulation of aggregated α-synuclein in the substantia nigra pars compacta (SNpc). Neuroinflammation associated with oxidative stress is a key factor contributing to the death of dopaminergic neurons in SNpc and advancement of Parkinson's disease. Two molecular targets, i.e., nuclear factor kappa-light-chain-enhancer (NF-kB) and α-synuclein play a substantial role in neuroinflammation progression. Therefore, the compounds targeting these neuroinflammatory targets hold a great potential to combat Parkinson's disease. Thereby, in this study, molecular docking and Connectivity Map (CMap) based gene expression profiling was utilized to reposition the approved drugs as neuroprotective agents for Parkinson's disease. With in silico screening, two drugs namely theophylline and propylthiouracil were selected for anti-neuroinflammatory activity evaluation in in vivo models of chronic neuroinflammation. The neuroinflammatory effect of the identified compounds was confirmed by quantifying the expression of three important neuroinflammatory mediators, i.e. IL-6, TNF-alpha, and IL-1 beta on brain tissue using ELISA assay. The ELISA experiment demonstrated that both compounds significantly decreased the expression of neuroinflammatory mediators, highlighting the compounds' potential in neuroinflammation management. Furthermore, the drug and disease interaction network of the two identified drugs and diseases (neuroinflammation and Parkinson's disease) suggested that the two drugs might interact with various targets namely adenosine receptors, Poly [ADP-ribose] polymerase-1, myeloperoxidase (MPO) and thyroid peroxidase through multiple pathways associated with neuroinflammation and Parkinson's disease. Computational studies suggest that a particular drug may be effective in managing Parkinson's disease associated with neuroinflammation. However, further research is needed to confirm this in biological experiments.

Anti-Skin Inflammatory and Anti-Oxidative Effects of the Neoflavonoid Latifolin Isolated from Dalbergia odorifera in HaCaT and BJ-5ta Cells

Skin is the first line of defense in the body against external stimulation and injury. Inflammation and oxidative stress in skin cells are the initiators and promoters of several skin diseases. Latifolin is a natural flavonoid isolated from Dalbergia odorifera T. Chen. This study aimed to evaluate the anti-inflammatory and antioxidant properties of latifolin. The anti-inflammatory effects were evaluated using tumor necrosis factor-α/interferon-γ (TNF-α/IFN-γ)-treated HaCaT cells, revealing that latifolin inhibited the secretion of Interleukin 6 (IL-6); Interleukin 8 (IL-8); Regulated upon Activation, Normal T Cell Expressed and Presumably Secreted (RANTES); and Macrophage-derived chemokine (MDC) while decreasing the expression of Intercellular Adhesion Molecule 1 (ICAM-1). The results of western blots and immunofluorescence demonstrated that the activation of Janus kinase 2 (JAK2), Signal transducer and activator of transcription 1 (STAT1), Signal transducer and activator of transcription 3 (STAT3), and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) cells signaling pathways were significantly inhibited by latifolin. The antioxidant properties were evaluated using t-BHP-induced BJ-5ta cells. Latifolin increased the viability of t-BHP-induced BJ-5ta cells. Additionally, fluorescent staining of reactive oxygen species (ROS) showed that the production of ROS was inhibited by latifolin. Additionally, latifolin reduced the phosphorylation of p38 and JNK. The results indicate that latifolin has potential anti-inflammatory and antioxidant properties, and may be a candidate natural compound for the treatment of skin diseases.

IFNAR signaling of neuroectodermal cells is essential for the survival of C57BL/6 mice infected with Theiler's murine encephalomyelitis virus

BACKGROUND

Theiler's murine encephalomyelitis virus (TMEV) is a single-stranded RNA virus that causes encephalitis followed by chronic demyelination in SJL mice and spontaneous seizures in C57BL/6 mice. Since earlier studies indicated a critical role of type I interferon (IFN-I) signaling in the control of viral replication in the central nervous system (CNS), mouse strain-specific differences in pathways induced by the IFN-I receptor (IFNAR) might determine the outcome of TMEV infection.

METHODS

Data of RNA-seq analysis and immunohistochemistry were used to compare the gene and protein expression of IFN-I signaling pathway members between mock- and TMEV-infected SJL and C57BL/6 mice at 4, 7 and 14 days post-infection (dpi). To address the impact of IFNAR signaling in selected brain-resident cell types, conditional knockout mice with an IFNAR deficiency in cells of the neuroectodermal lineage (NesCre^±IFNAR^fl/fl), neurons (Syn1Cre^±IFNAR^fl/fl), astrocytes (GFAPCre^±IFNAR^fl/fl), and microglia (Sall1Cre^ER±IFNAR^fl/fl) on a C57BL/6 background were tested. PCR and an immunoassay were used to quantify TMEV RNA and cytokine and chemokine expression in their brain at 4 dpi.

RESULTS

RNA-seq analysis revealed upregulation of most ISGs in SJL and C57BL/6 mice, but Ifi202b mRNA transcripts were only increased in SJL and Trim12a only in C57BL/6 mice. Immunohistochemistry showed minor differences in ISG expression (ISG15, OAS, PKR) between both mouse strains. While all immunocompetent Cre-negative control mice and the majority of mice with IFNAR deficiency in neurons or microglia survived until 14 dpi, lack of IFNAR expression in all cells (IFNAR^-/-), neuroectodermal cells, or astrocytes induced lethal disease in most of the analyzed mice, which was associated with unrestricted viral replication. NesCre^±IFNAR^fl/fl mice showed more Ifnb1, Tnfa, Il6, Il10, Il12b and Ifng mRNA transcripts than Cre^-/-IFNAR^fl/fl mice. IFNAR^-/- mice also demonstrated increased IFN-α, IFN-β, IL1-β, IL-6, and CXCL-1 protein levels, which highly correlated with viral load.

CONCLUSIONS

Ifi202b and Trim12a expression levels likely contribute to mouse strain-specific susceptibility to TMEV-induced CNS lesions. Restriction of viral replication is strongly dependent on IFNAR signaling of neuroectodermal cells, which also controls the expression of key pro- and anti-inflammatory cytokines during viral brain infection.

The Role of ERK1/2 Pathway in the Pathophysiology of Alzheimer's Disease: An Overview and Update on New Developments

Alzheimer's disease (AD) is the most common neurodegenerative disorder worldwide. Several findings suggest that correcting the dysregulated signaling pathways may offer a potential therapeutic approach in this disease. Extracellular signal-regulated kinase 1/2 (ERK1/2), a member of the mitogen-activated protein kinase family, plays a major role in regulation of cell proliferation, autophagy process, and protein synthesis. The available literature suggests dysregulated ERK1/2 in AD patients with potential implications in the multifaceted underlying pathologies of AD, including amyloid-β plaque formation, tau phosphorylation, and neuroinflammation. In this regard, in the current review, we aim to summarize the reports on the potential roles of ERK1/2 in AD pathophysiology.

Chick early amniotic fluid component improves heart function and protects against inflammation after myocardial infarction in mice

Myocardial infarction (MI) is the major cause of mortality around the world. We recently demonstrated that chick early amniotic fluid (ceAF) can effectively rescue ischemic heart injury, indicating that it has a therapeutic function in MI. However, its functional components and the underlying mechanisms remain to be clarified. Here, we demonstrated that a fraction of ceAF, peak 8 (P8), had a protective effect on acute MI. P8 significantly decreased cardiomyocyte cross-sectional areas and cardiomyocyte apoptosis in MI mice. Using a human embryonic stem cell-derived cardiomyocyte model, which was subjected to hypoxia and reoxygenation, mimicking MI state, we found that P8 treatment reduced apoptosis and reversed myocardial contractility. Mechanistically, P8 improved cardiac function by inhibiting NF-κB signaling and downregulating inflammatory cytokine expression. Using mass spectrometry, we identified that guanosine and deoxynucleoside were the main functional components of P8 that suppressed the inflammatory response in human embryonic stem cell-derived cardiomyocytes. Collectively, our data suggest that specific components from ceAF are promising therapeutic agents for ischemic heart injury and could be a potential supplement to current medications for MI.

Matrin3 (MATR3) Expression Is Associated with Hemophagocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome characterized by prolonged fever, cytopenia, hepatosplenomegaly, and hemophagocytosis. This occurs as a result of activated macrophages and impaired function of natural killer cells and/or cytotoxic T lymphocytes. The NF-κB pathway plays a crucial role in hyperinflammation. Matrin3 (MATR3) is a nuclear RNA/DNA-binding protein that plays multiple roles in the regulation of gene expression. We enroll 62 patients diagnosed with secondary HLH and hemophagocytosis. Peripheral blood (PB) from 25 patients and 30 healthy volunteers and good quality bone marrow (BM) samples from 47 patients are collected and used for analysis. Clinical parameters, including age, sex, etiology, ferritin, fibrinogen, triglyceride, and viral infection status, had no association with survival prediction. Patients with downregulation of NF-κB and MATR3mRNA expression in the BM had a higher mortality rate. MATR3mRNA expression in PB was lower in patients compared to that in healthy volunteers. We use shRNA-MATR3-KD-THP1 cells to determine the efficacy of phagocytosis. We note that shRNA-MATR3-KD-THP1 cells had a higher phagocytic effect on necrotic Jurkat E6 cells and carboxylate modified polystyrene latex beads. Herein, we provide evidence of a new marker for clinical translation that can serve as a potential treatment target for secondary HLH.

SUMOylation of Dorsal attenuates Toll/NF-κB signaling

In Drosophila, Toll/NF-κB signaling plays key roles in both animal development and in host defense. The activation, intensity, and kinetics of Toll signaling are regulated by posttranslational modifications such as phosphorylation, SUMOylation, or ubiquitination that target multiple proteins in the Toll/NF-κB cascade. Here, we have generated a CRISPR-Cas9 edited Dorsal (DL) variant that is SUMO conjugation resistant. Intriguingly, embryos laid by dlSCR mothers overcome dl haploinsufficiency and complete the developmental program. This ability appears to be a result of higher transcriptional activation by DLSCR. In contrast, SUMOylation dampens DL transcriptional activation, ultimately conferring robustness to the dorso-ventral program. In the larval immune response, dlSCR animals show an increase in crystal cell numbers, stronger activation of humoral defense genes, and high cactus levels. A mathematical model that evaluates the contribution of the small fraction of SUMOylated DL (1-5%) suggests that it acts to block transcriptional activation, which is driven primarily by DL that is not SUMO conjugated. Our findings define SUMO conjugation as an important regulator of the Toll signaling cascade, in both development and host defense. Our results broadly suggest that SUMO attenuates DL at the level of transcriptional activation. Furthermore, we hypothesize that SUMO conjugation of DL may be part of a Ubc9-dependent mechanism that restrains Toll/NF-κB signaling.

Immune-Enhancing Effect of Submerged Culture of Ceriporia lacerata Mycelia on Cyclophosphamide-Induced Immunosuppressed Mice and the Underlying Mechanisms in Macrophages

The white-rot fungi Ceriporia lacerata is used in bioremediation, such as lignocellulose degradation, in nature. Submerged cultures and extracts of C. lacerata mycelia (CLM) have been reported to contain various active ingredients, including β-glucan and extracellular polysaccharides, and to exert anti-diabetogenic properties in mice and cell lines. However, the immunostimulatory effects have not yet been reported. This study aimed to identify the immunomodulatory effects, and underlying mechanisms thereof, of submerged cultures of CLM using RAW264.7 macrophages and cyclophosphamide (CTX)-induced immunosuppression in mice. Compared to CTX-induced immunosuppressed mice, the spleen and thymus indexes in mice orally administered CLM were significantly increased; body weight loss was alleviated; and natural killer (NK) cytotoxicity, lymphocyte proliferation, and cytokine (tumor necrosis factor [TNF]-α, interferon [IFN]-γ, and interleukin [IL]-2) production were elevated in the serum. In RAW264.7 macrophages, treatment with CLM induced phagocytic activity, increased the production of nitric oxide (NO), and promoted mRNA expression of the immunomodulatory cytokines TNF-α, IFN-γ, IL-1β, IL-6, IL-10, and IL-12. In addition, CLM increased the inducible NO synthase (iNOS) concentration in macrophages, similar to lipopolysaccharide (LPS) stimulation. Mechanistic studies showed that CLM induced the activation of the NF-κB, PI3k/Akt, ERK1/2, and JNK1/2 pathways. Moreover, the phosphorylation of NF-κB and IκB induced by CLM in RAW264.7 cells was suppressed by specific MAPKs and PI3K inhibitors. Further experiments with a TLR4 inhibitor demonstrated that the production of TNF-α, IL-1β, and IL-6 induced by CLM was decreased after TLR4 was blocked. Overall, CLM protected against CTX-induced adverse reactions by enhancing humoral and cellular immune functions, and has potential as an immunomodulatory agent.

Differential Transcriptomic Response of Rainbow Trout to Infection with Two Strains of IPNV

The IPN virus (IPNV) causes a highly contagious disease that affects farmed salmonids. IPNV isolates have been phylogenetically classified into seven genogroups, of which two are present in Chile, genogroups 1 and 5. This study aimed to compare the transcriptomic response of rainbow trout fry challenged with two Chilean isolates of IPNV, RTTX (genogroup 1), and ALKA (genogroup 5). Tissue samples from challenged individuals and controls were taken at 1, 7, and 20 days post-challenge and analyzed by RNA-Seq. The results revealed that infection with RTTX elicited a greater modulation of the trout transcriptome compared to ALKA infection, generating a greater number of highly differentially expressed genes in relation to the control fish. Gene Ontology enrichment indicated that functions related to the inflammatory and immune responses were modulated in fish challenged with both isolates throughout the trial, but with different regulation patterns. On day 1 post challenge, these functions were activated in those challenged with ALKA, but suppressed in RTTX-challenged fish. These results suggest that rainbow trout exhibit a differential transcriptomic response to infection with the two genetically distinct IPNV isolates, especially at early times post-infection.

Structure and immunomodulatory activity of a water-soluble α-glucan from Hirsutella sinensis mycelia

Hirsutella sinensis, the anamorph of Ophiocordyceps sinensis (syn. Cordyceps sinensis), is a great substitute for precious and rare wild Cordyceps sinensis to effectively treat a variety of lung and kidney diseases. In this study, an α-glucan (named as HSWP-2a) was obtained by hot water extraction, DEAE-cellulose separation, and Sepharose CL-6B purification from H. sinensis mycelia. Different from known α-glucans, HSWP-2a is an α-(1 → 4)-D-glucan that branched at O-6, O-3, or O-2 with a terminal 1-linked α-D-Glcp as side chain, with an average molecular weight of 870.70 kDa. Immunological tests showed that HSWP-2a could remarkably enhance the phagocytosis of macrophages and increase the production of NO, IL-1β, IL-6, and TNF-α, via activating the p38, JNK, and NF-κB signaling pathways. Moreover, HSWP-2a could significantly promote splenic lymphocyte proliferation. Taken together, HSWP-2a may be potentially utilized as a natural immunomodulatory agent.

DES-Tcell is a knowledgebase for exploring immunology-related literature

T-cells are a subtype of white blood cells circulating throughout the body, searching for infected and abnormal cells. They have multifaceted functions that include scanning for and directly killing cells infected with intracellular pathogens, eradicating abnormal cells, orchestrating immune response by activating and helping other immune cells, memorizing encountered pathogens, and providing long-lasting protection upon recurrent infections. However, T-cells are also involved in immune responses that result in organ transplant rejection, autoimmune diseases, and some allergic diseases. To support T-cell research, we developed the DES-Tcell knowledgebase (KB). This KB incorporates text- and data-mined information that can expedite retrieval and exploration of T-cell relevant information from the large volume of published T-cell-related research. This KB enables exploration of data through concepts from 15 topic-specific dictionaries, including immunology-related genes, mutations, pathogens, and pathways. We developed three case studies using DES-Tcell, one of which validates effective retrieval of known associations by DES-Tcell. The second and third case studies focuses on concepts that are common to Grave’s disease (GD) and Hashimoto’s thyroiditis (HT). Several reports have shown that up to 20% of GD patients treated with antithyroid medication develop HT, thus suggesting a possible conversion or shift from GD to HT disease. DES-Tcell found miR-4442 links to both GD and HT, and that miR-4442 possibly targets the autoimmune disease risk factor CD6, which provides potential new knowledge derived through the use of DES-Tcell. According to our understanding, DES-Tcell is the first KB dedicated to exploring T-cell-relevant information via literature-mining, data-mining, and topic-specific dictionaries.

The Effects of Selenium in Acrylamide-Induced Nephrotoxicity in Rats: Roles of Oxidative Stress, Inflammation, Apoptosis, and DNA Damage

We sought to determine the effects of selenium (Se) on acrylamide (ACR)-induced nephrotoxicity in rats. In our study, 50 adult male Sprague-Dawley rats weighing 200-250 g were randomly divided into five groups. The control group was given intra-gastric (i.g.) saline (1 mL) for 10 days. The ACR group was given i.g. ACR in saline (38.27 mg/kg titrated to 1 mL) for 10 days. The Se0.5 + ACR and Se1 + ACR groups were administered Se in saline (0.5 and 1 mg/kg, respectively) for 10 days and given i.g. ACR (38.27 mg/kg) one hour after the Se injections. The Se1 group was administered i.g. Se (1 mg/kg) for 10 days. On day 11, intracardiac blood samples were obtained from the rats while they were under anesthesia, after which they were euthanized by decapitation. Urea and creatinine concentrations of blood serum samples were analyzed with an autoanalyzer. Enzyme-linked immunosorbence immunosorbent assay (ELISA) was used to quantify malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), tumor necrosis factor-α (TNF-α), nuclear factor-κB (NF-κB), interleukin (IL)-33, IL-6, IL-1β, cyclooxygenase-2 (COX-2), kidney injury molecule-1 (KIM-1), mitogen-activated protein kinase-1 (MAPK-1), and caspase-3 in kidney tissues. Renal tissues were evaluated by histopathological and immunohistochemical examinations for 8-hydroxylo-2'-deoxyguanosin 8-hydroxy-2'-deoxyguanosine (8-OhDG) and Bax. Serum urea and creatinine levels were higher in the ACR group than in the control, and these ACR-induced increases were prevented by high doses of Se. Additionally, ACR induced the renal oxidative stress, inflammation, apoptosis, and damage to DNA and tissue; likewise, these were prevented by high doses of Se. Taken with ACR, Se confers protection against ACR-induced nephrotoxicity in rats by reducing oxidative stress, inflammation, apoptosis, and DNA damage.

3α-Angeloyloxy-ent-kaur-16-en-19-oic Acid Isolated from Wedelia trilobata L. Alleviates Xylene-Induced Mouse Ear Edema and Inhibits NF-κB and MAPK Pathway in LPS-Stimulated Macrophages

Uncontrolled inflammation is associated with many major diseases, and there is still an urgent need to develop new anti-inflammatory drugs. 3α-Angeloyloxy-ent-kaur-16-en-19-oic acid (WT-25) is an ent-kaurane dieterpenoid extracted from Wedelia trilobata, a medicinal plant with potential anti-inflammatory activity. The anti-inflammatory activity of WT-25 is better than that of its analog kaurenoic acid, but the underlying mechanism is still unknown. In this study, our aim was to study the anti-inflammatory effect of WT-25. In xylene-induced edema in mice, WT-25 produced 51% inhibition. WT-25 suppressed nitric oxide (NO) and prostaglandin E2 (PGE₂) production in LPS-stimulated RAW264.7 cells by downregulating the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). WT-25 reduced expression and secretion of TNF-α and IL-6. Moreover, WT-25 inhibited NF-κB activation and its upstream signaling, decreasing phosphorylation IKK and p65 levels. WT-25 also inhibited the phosphorylation of the mitogen-activated protein kinases (MAPKs) family. Additionally, it reduced LPS-induced excessive release of reactive oxygen species (ROS) and maintained mitochondrial integrity in RAW264.7 cells. All these results indicate that WT-25 is a bioactive molecule with the potential to be developed as a novel structured anti-inflammatory drug.

IRF11 enhances the inhibitory effect of IκBα on NF-κB activation in miiuy croaker

NF-κB is a typical transcription factor that regulates expression of various genes involved in inflammatory and immune responses. Therefore, it is essential that NF-κB signaling tightly regulated to maintain immune balance. Compared with those of mammals, the regulatory mechanisms of NF-κB signaling is rarely reported in teleost fish. IκBα is a prominent negative feedback regulator in the NF-κB signaling system. In this study, we determined that IRF11 enhances the inhibitory effect of IκBα on NF-κB activation in teleost fish. Overexpression of IRF11 can inhibit IκBα degradation, whereas its knockdown has the opposite effect of IκBα. Our study further indicates that IκBα was regulated via ubiquitin-proteasome degradation pathway, IRF11 inhibits IκBα in ubiquitin-proteasome degradation. This study provides a novel evidence on the regulation of innate immune signaling pathways in teleost fish and thus provides new insights into the regulatory mechanisms in mammals.

Differential responses in placenta and fetal thymus at 12 days post infection elucidate mechanisms of viral level and fetal compromise following PRRSV2 infection

BACKGROUND

A pregnant gilt infected with porcine reproductive and respiratory syndrome virus (PRRSV) can transmit the virus to her fetuses across the maternal-fetal-interface resulting in varying disease outcomes. However, the mechanisms leading to variation in fetal outcome in response to PRRSV infection are not fully understood. Our objective was to assess targeted immune-related gene expression patterns and pathways in the placenta and fetal thymus to elucidate the molecular mechanisms involved in the resistance/tolerance and susceptibility of fetuses to PRRSV2 infection. Fetuses were grouped by preservation status and PRRS viral load (VL): mock infected control (CTRL), no virus detected (UNINF), virus detected in the placenta only with viable (PLCO-VIA) or meconium-stained fetus (PLCO-MEC), low VL with viable (LVL-VIA) or meconium-stained fetus (LVL-MEC), and high VL with viable (HVL-VIA) or meconium-stained fetus (HVL-MEC).

RESULTS

The host immune response was initiated only in fetuses with detectable levels of PRRSV. No differentially expressed genes (DEG) in either the placenta or thymus were identified in UNINF, PLCO-VIA, and PLCO-MEC when compared to CTRL fetuses. Upon fetal infection, a set of core responsive IFN-inducible genes (CXCL10, IFIH1, IFIT1, IFIT3, ISG15, and MX1) were strongly upregulated in both tissues. Gene expression in the thymus is a better differentiator of fetal VL; the strong downregulation of several innate and adaptive immune pathways (e.g., B Cell Development) are indicative of HVL. Gene expression in the placenta may be a better differentiator of fetal demise than the thymus, based-on principle component analysis clustering, gene expression patterns, and dysregulation of the Apoptosis and Ubiquitination pathways.

CONCLUSION

Our data supports the concept that fetal outcome in response to PRRSV2 infection is determined by fetal, and more significantly placental response, which is initiated only after fetal infection. This conceptual model represents a significant step forward in understanding the mechanisms underpinning fetal susceptibility to the virus.

Treatment of non-erosive reflux disease and dynamics of the esophageal microbiome: a prospective multicenter study

Non-erosive reflux disease (NERD) pathogenesis has not been thoroughly evaluated. Here, we assessed the response of patients with NERD to proton pump inhibitor (PPI) therapy; changes in the microbiome and biologic marker expression in the esophageal mucosa were also evaluated. Patients with NERD (n = 55) received esomeprazole (20 mg) for eight weeks. The treatment response was evaluated at baseline, week four, and week eight. Esophageal mucosal markers and oropharyngeal and esophageal microbiomes were analyzed in patients who underwent upper gastrointestinal endoscopy at screening (n = 18). Complete and partial response rates at week eight were 60.0% and 32.7% for heartburn, and 61.8% and 29.1% for regurgitation, respectively. The expressions of several inflammatory cytokines, including IL-6, IL-8, and NF-κB, were decreased at week eight. Streptococcus, Haemophilus, Prevotella, Veillonella, Neisseria, and Granulicatella were prevalent regardless of the time-point (baseline vs. week eight) and organ (oropharynx vs. esophagus). The overall composition of oropharyngeal and esophageal microbiomes showed significant difference (P = 0.004), which disappeared after PPI therapy. In conclusion, half-dose PPI therapy for eight weeks could effectively control NERD symptoms. The expression of several inflammatory cytokines was reduced in the esophagus, and oropharyngeal and esophageal microbiomes in patients with NERD showed significant difference. However, the microbial compositions in the oropharynx and esophagus were not affected by PPI therapy in this study. Impact of PPI on the microbiome in patients with NERD should be more investigated in future studies.

Molecular and cellular mechanisms of the effects of Propolis in inflammation, oxidative stress and glycemic control in chronic diseases

Propolis is a sticky, resinous material gather from plants and is blended with wax and other constituents. It is reported to have anti-inflammatory, anti-oxidative and blood glucose-lowering properties. This review aims to summarise evidences for the cellular and molecular mechanism of Propolis in inflammation, oxidative stress, and glycemic control. Propolis stimulate the production and secretion of anti-inflammatory cytokines and to inhibit the production of inflammatory cytokines and due to its various antioxidant and poly-phenolic compounds may has a role in control and treating some of the chronic diseases. Most studies have shown that Propolis may affect metabolic factors including plasma insulin levels, and it has proposed that it could be used in the prevention and treatment of T2D Mellitus. In general, to demonstrate the definite effects of Propolis on chronic diseases, more studies are required using larger sample sizes and various doses of Propolis, using better characterized and standardized agents.

Standardized ethanol extract of Tinospora crispa upregulates pro-inflammatory mediators release in LPS-primed U937 human macrophages through stimulation of MAPK, NF-κB and PI3K-Akt signaling networks

BACKGROUND

Immunomodulatory effects of Tinospora crispa have been investigated due to its traditional use to treat several inflammatory disorders associated to the immune system. The present study reports the underlying mechanisms involved in the stimulation of 80% ethanol extract of T. crispa stems on pro-inflammatory mediators release in lipopolysaccharide (LPS)-primed U937 human macrophages via MyD88-dependent pathways.

METHODS

Release of interleukin (IL)-1β and tumor necrosis factor (TNF)-α, and production of prostaglandin E₂ (PGE₂) were determined by using enzyme-linked immunosorbent assay (ELISA). Immunoblot technique was executed to determine the activation of MAPKs molecules, NF-κB, PI3K-Akt and cyclooxygenase-2 (COX-2) protein. Determination of pro-inflammatory cytokines and COX-2 relative gene expression levels was by performing the real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). A reversed-phase HPLC method was developed and validated to standardize the T. crispa extract and chemical profiling of its secondary metabolites was performed by LC-MS/MS.

RESULTS

Qualitative and quantitative analyses of chromatographic data indicated that syringin and magnoflorine were found as the major components of the extract. T. crispa-treatment prompted activation of NF-κB by enhancing IKKα/β and NF-κB (p65) phosphorylation, and degradation of IκBα. The extract upregulated COX-2 protein expression, release of pro-inflammatory mediators and MAPKs (ERK, p38 and JNK) phosphorylation as well as Akt dose-dependently. T. crispa extract also upregulated the upstream signaling adaptor molecules, toll-like receptor 4 (TLR4) and MyD88. T. crispa-treatment also upregulated the pro-inflammatory markers mRNA expression.

CONCLUSION

The results suggested that T. crispa extract stimulated the MyD88-dependent signaling pathways by upregulating the various immune inflammatory related parameters.

Immunomodulatory Activity of Lactococcus lactis GCWB1176 in Cyclophosphamide-Induced Immunosuppression Model

Recently, Lactococcus lactis subsp. lactis has been reported to have immunostimulating properties in an immunosuppressed-animal model. However, the immunological activities of Lactococcus lactis and the molecular mechanisms remain unclear. In this report, we evaluated the immunostimulating activity and associated mechanisms of Lactococcus lactis subsp. lactis GCWB1176 (GCWB1176) in macrophages and cyclophosphamide (CTX)-induced immunosuppressed mice. In a series of safety tests, GCWB1176 was found to have a negative response to hemolysis, as well as susceptibility to antibiotics. Administration of GCWB1176 elevated natural killer (NK) cell activities; concanavalin A-induced T cell proliferation; and serum levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-10 and IL-12 in CTX-induced immunosuppressed mice. In RAW264.7 macrophages, treatment with GCWB1176 induced phagocytic activity and increased the production of nitric oxide (NO) and expression of inducible NO synthase. Simultaneously, GCWB1176 increased the production of TNF-α, IFN-γ, IL-1β, IL-10 and IL-12 from mouse splenocytes and RAW264.7 cells. In addition, GCWB1176 significantly increased the transcriptional activities of NF-κB and iNOS. Taken together, GCWB1176 improved immune function through the activation of macrophages and NK cells. These findings suggest that dietary supplementation of GCWB1176 may be used to enhance immunity.

Aspartic Aminopeptidase Is a Novel Biomarker of Aggressive Chronic Lymphocytic Leukemia

Treatment of chronic lymphocytic leukemia has advanced substantially as our understanding of the kinase signal transduction pathways driven by the B cell receptor (BcR) has developed. Particularly, understanding the role of Bruton tyrosine kinase and phosphatidyl inositol 3 kinase delta in driving prosurvival signal transduction in chronic lymphocytic leukemia (CLL) cells and their targeting with pharmacological inhibitors (ibrutinib and idelalisib, respectively) has improved patient outcomes significantly. The kinase signaling pathway induced by the BcR is highly complex and has multiple interconnecting branches mediated by tyrosine and serine/threonine kinases activated downstream of the BcR. There is a high level of redundancy in the biological responses, with several BcR-signaling kinases driving nuclear factor kappa B activation or inducing antiapoptotic Bcl-2 genes. Accordingly, common gene targets of BcR-signaling kinases may serve as biomarkers indicating enhanced BCR-signaling and aggressive disease progression. This study used a gene expression correlation analysis of malignant B cell lines and primary CLL cells to identify genes whose expression correlated with BCR-signaling kinases overexpressed and/or overactivated in CLL, namely: AKT1, AKT2, BTK, MAPK1, MAPK3, PI3KCD and ZAP70. The analysis identified a 32-gene signature with a strong prognostic potential and DNPEP, the gene coding for aspartic aminopeptidase, as a predictor of aggressive CLL. DNPEP gene expression correlated with MAPK3, PI3KCD, and ZAP70 expression and, in the primary CLL test dataset, showed a strong prognostic potential. The inhibition of DNPEP with a pharmacological inhibitor enhanced the cytotoxic potential of idelalisib and ibrutinib, indicating a biological functionality of DNPEP in CLL. DNPEP, as an aminopeptidase, contributes to the maintenance of the free amino acid pool in CLL cells found to be an essential process for the survival of many cancer cell types, and thus, these results warrant further research into the exploitation of aminopeptidase inhibitors in the treatment of drug-resistant CLL.

Grass carp (Ctenopharyngodon idella) Bcl-xl: transcriptional regulation and anti-apoptosis analysis

Bcl-xl, Bax2, and NF-κB are well-known to be involved in anti-apoptosis response. Although Bcl-xl has been reported in fish, the NF-κB-mediated regulatory mechanism and anti-apoptotic function are still unclear. Here, we cloned and characterized the full-length cDNA sequence of grass carp (Ctenopharyngodon idella) Bcl-xl (CiBcl-xl) and its promoter region sequence. The full-length cDNA of CiBcl-xl is 2836 bp with an ORF of 627 bp encoding a polypeptide of 208 amino acids. Phylogenetic tree analysis revealed that CiBcl-xl shared high homology with Dario rerio Bcl-xl (DrBcl-xl). After stimulation with Poly I:C, the expression of CiBcl-xl in CIK cells and various tested tissues of grass carp were significantly upregulated. To further understand the transcriptional control of fish Bcl-xl induced by NF-κB, CiC-rel and Cip65 were expressed in Escherichia coli BL21 and purified by affinity chromatography with the Ni-NTA His-Bind resin. In vitro, gel mobility shift assays demonstrated the high affinity of CiC-rel and Cip65 with CiBcl-xl promoter. Dual-luciferase reporter assays showed that CiC-rel and Cip65 activated CiBcl-xl promoter. Also, knockdown of CiC-rel and Cip65 reduced the expression of Bcl-xl. Therefore, similar to those of mammals, fish C-rel and p65 can upregulate the transcription of Bcl-xl. In addition, we found that overexpression of CiBcl-xl in CIK cells increased the cell activity and inhibited cell apoptosis, while overexpression of Bax2 promoted cell apoptosis. Meanwhile, co-transfection of CiBcl-xl and CiBax2 into cells can ease up apoptotic rate. To further investigate the molecular basis of synergistic effect of Bcl-xl and Bax2, we showed that Bcl-xl and Bax2 interacted with each other. The results suggested that Bcl-xl executed its anti-apoptotic function by binding to and inhibiting the pro-apoptotic activity of Bax2.

RIG-I aggravates interstitial fibrosis via c-Myc-mediated fibroblast activation in UUO mice

Abstract

Progressive tubulointerstitial fibrosis is the common final outcome for all kidney diseases evolving into chronic kidney disease (CKD), whereas molecular mechanisms driving fibrogenesis remain elusive. Retinoic acid-inducible gene-I (RIG-I), an intracellular pattern recognition receptor, is originally identified participating in immune response by recognizing virus RNA. Here, we revealed for the first time that RIG-I was induced in unilateral ureteral obstruction (UUO) and folic acid (FA) renal fibrosis models and moderate-degree renal fibrosis patients. Besides, we found RIG-I was mainly located in renal tubular epithelial cells and promoted the production and release of inflammatory cytokines, such as interleukin (IL)-1β and IL-6 through activation of NF-κB. Inflammatory cytokines released by tubular epithelial cells activated c-Myc-mediated TGF-β/Smad signaling in fibroblasts, which in turn aggravated interstitial fibrosis by promoting fibroblast activation and production of extracellular matrix components (ECM). Deficiency of RIG-I attenuated renal fibrosis by the regulation of inflammatory responses, c-Myc expression, and fibroblast activation. Besides, gene silencing of RIG-I reduced inflammatory cytokines in cultured tubular epithelial cells treated with Angiotensin II. Knockdown of c-Myc or c-Myc inhibitor blocked IL-1β-induced fibroblast activation. Collectively, our study demonstrates that RIG-I plays a significant role in the progress of renal fibrosis via regulating c-Myc-mediated fibroblast activation.

Key messages

• RIG-I was constantly elevated in kidneys from renal fibrotic mice.

• RIG-I facilitated inflammatory cytokine production in tubular epithelial cells.

• RIG-I aggravated renal fibrosis via c-Myc-mediated TGF-β/Smad activation.

Dopamine activates NF-κB and primes the NLRP3 inflammasome in primary human macrophages

Induction of innate immune genes in the brain is thought to be a major factor in the development of addiction to substances of abuse. As the major component of the innate immune system in the brain, aberrant activation of myeloid cells such as macrophages and microglia due to substance use may mediate neuroinflammation and contribute to the development of addiction. All addictive drugs modulate the dopaminergic system and our previous studies have identified dopamine as a pro-inflammatory modulator of macrophage function. However, the mechanism that mediates this effect is currently unknown. Inflammatory activation of macrophages and induction of cytokine production is often mediated by the transcription factor NF-κB, and prior studies have shown that dopamine can modulate NF-κB activity in T-cells and other non-immune cell lines. Here we demonstrated that dopamine can activate NF-κB in primary human macrophages, resulting in the induction of its downstream targets including the NLRP3 inflammasome and the inflammatory cytokine IL-1β. These data also indicate that dopamine primes but does not activate the NLRP3 inflammasome in human macrophages. Activation of NF-κB was required for dopamine-mediated increases in IL-1β, as an inhibitor of NF-κB was able to abrogate the effects of dopamine on production of these cytokines. Connecting an increase in extracellular dopamine to NF-κB activation and inflammation suggests specific intracellular targets that could be used to ameliorate the inflammatory impact of dopamine in neuroinflammatory conditions associated with myeloid cell activation such as addiction.

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Dopamine exposure primes, but does not activate the NLRP3 inflammasome.

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Inflammasome priming can be mediated, at least partially, by a dopamine-induced increase in the activation and nuclear translocation of NF-κB in primary human macrophages.

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Dopamine additively increases the impact of cytomegalovirus on NF-κB activation in macrophages.

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Dopamine priming increases IL-1β release in response to inflammasome activation.

The immune-modulating effects of viable Weissella cibaria JW15 on RAW 264.7 macrophage cells

The objective of this study is to investigate the immune-enhancing ability of viable and heat-killed Weissella cibaria JW15 (JW15) isolated from Kimchi in RAW 264.7 macrophages. The immune effects were evaluated by measuring the production of NO, cytokines, inflammatory enzyme, and activation of NF-κB. Viable JW15 executed higher activity on stimulating the release of TNF-α as well as activating NF-κB compared to that of heat-killed JW15. Additionally, viable and heat-killed JW15 significantly increased the production of NO, IL-6 and TNF-α more than that of Lactobacillus rhamnosus GG (LGG). Furthermore, viable JW15 induced higher production of iNOS compared with that of viable LGG. Collectively, our finding indicates that viable JW15 had similar, if not more, immune-enhancing activities as heat-killed JW15. In addition, viable JW15 had higher immune-enhancing activity than commercial strain LGG. Therefore, viable JW15 has the potential to be used as a functional food to improve the host immune response.

Enhancement of Macrophage Function by the Antimicrobial Peptide Sublancin Protects Mice from Methicillin-Resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is the major pathogen responsible for community and hospital bacterial infections. Sublancin, a glucosylated antimicrobial peptide isolated from Bacillus subtilis 168, possesses antibacterial infective effects. In this study, we investigated the role and anti-infection mechanism of sublancin in a mouse model of MRSA-induced sublethal infection. Sublancin could modulate innate immunity by inducing the production of IL-1β, IL-6, TNF-α, and nitric oxide, enhancing phagocytosis and MRSA-killing activity in both RAW264.7 cells and mouse peritoneal macrophages. The enhanced macrophage function by the peptide in vitro correlated with stronger protective activity in vivo in the MRSA-invasive sublethal infection model. Macrophage activation by sublancin was found to be partly dependent on TLR4 and the NF-κB and MAPK signaling pathways. Moreover, oral administration of sublancin increased the frequencies of CD⁴⁺ and CD⁸⁺ T cells in mesenteric lymph nodes. The protective activity of sublancin was associated with in vivo augmenting phagocytic activity of peritoneal macrophages and partly improving T cell-mediated immunity. Macrophages thus represent a potentially pivotal and novel target for future development of innate defense regulator therapeutics against S. aureus infection.

Anti-inflammatory and Proapoptotic Properties of the Natural Compound o-Orsellinaldehyde

Metabolic syndrome is a cluster of medical conditions that increases the risk of developing cardiovascular disease and type 2 diabetes. Numerous studies have shown that inflammation is directly involved in the onset of metabolic syndrome and related pathologies. In this study, in silico techniques were applied to a natural products database containing molecules isolated from mushrooms from the Catalan forests to predict molecules that can act as human nuclear-factor κβ kinase 2 (IKK-2) inhibitors. IKK-2 is the main component responsible for activating the nuclear-factor κβ transcription factor (NF-κβ). One of these predicted molecules was o-orsellinaldehyde, a molecule present in the mushroom Grifola frondosa. This study shows that o-orsellinaldehyde presents anti-inflammatory and pro-apoptotic properties by acting as IKK-2 inhibitor. Additionally, we suggest that the anti-inflammatory and pro-apoptotic properties of Grifola frondosa mushroom could partially be explained by the presence of o-orsellinaldehyde on its composition.

Complexes of Oligoribonucleotides with d-Mannitol Modulate the Innate Immune Response to Influenza A Virus H1N1 (A/FM/1/47) In Vivo

Rapid replication of the influenza A virus and lung tissue damage caused by exaggerated pro-inflammatory host immune responses lead to numerous deaths. Therefore, novel therapeutic agents that have anti-influenza activities and attenuate excessive pro-inflammatory responses that are induced by an influenza virus infection are needed. Oligoribonucleotides-d-mannitol (ORNs-d-M) complexes possess both antiviral and anti-inflammatory activities. The current research was aimed at studying the ORNs-d-M effects on expression of innate immune genes in mice lungs during an influenza virus infection. Expression of genes was determined by RT-qPCR and Western blot assays. In the present studies, we found that the ORNs-d-M reduced the influenza-induced up-expression of Toll-like receptors (TLRs) (tlr3, tlr7, tlr8), nuclear factor NF-kB (nfkbia, nfnb1), cytokines (ifnε, ifnk, ifna2, ifnb1, ifnγ, il6, il1b, il12a, tnf), chemokines (ccl3, ccl4, сcl5, cxcl9, cxcl10, cxcl11), interferon-stimulated genes (ISGs) (oas1a, oas2, oas3, mx1), and pro-oxidation (nos2, xdh) genes. The ORNs-d-M inhibited the mRNA overexpression of tlr3, tlr7, and tlr8 induced by the influenza virus, which suggests that they impair the upregulation of NF-kB, cytokines, chemokines, ISGs, and pro-oxidation genes induced by the influenza virus by inhibiting activation of the TLR-3, TLR-7, and TLR-8 signaling pathways. By impairing activation of the TLR-3, TLR-7, and TLR-8 signaling pathways, the ORNs-d-M can modulate the innate immune response to an influenza virus infection.

Pulmonary Administration of Microparticulate Antisense Oligonucleotide (ASO) for the Treatment of Lung Inflammation

Targeted delivery to the lung for controlling lung inflammation is an area that we have explored in this study. The purpose was to use microparticles containing an antisense oligonucleotide (ASO) to NF-κB to inhibit the production of proinflammatory cytokines. Microparticles were prepared using the B-290 Buchi Spray Dryer using albumin as the microparticle matrix. Physicochemical characterization of the microparticles showed the size ranged from 2 to 5 μm, the charge was - 38.4 mV, and they had a sustained release profile over 72 h. Uptake of FITC-labeled ASO-loaded microparticles versus FITC-labeled ASO solution by RAW264.7 murine macrophage cells was 5-10-fold higher. After pulmonary delivery of microparticles to Sprague-Dawley rats, the microparticles were uniformly distributed throughout the lung and were retained in the lungs until 48 h. Serum cytokine (TNF-α and IL-1β) levels of rats after induction of lung inflammation by lipopolysaccharide were measured until 72 h. Animals receiving ASO-loaded microparticles were successful in significantly controlling lung inflammation during this period as compared to animals receiving no treatment. This study was successful in proving that microparticulate ASO therapy was capable of controlling lung inflammation.

Activation of Toll-like receptors nucleates assembly of the MyDDosome signaling hub

Infection and tissue damage induces assembly of supramolecular organizing centres (SMOCs)), such as the Toll-like receptor (TLR) MyDDosome, to co-ordinate inflammatory signaling. SMOC assembly is thought to drive digital all-or-none responses, yet TLR activation by diverse microbes induces anything from mild to severe inflammation. Using single-molecule imaging of TLR4-MyDDosome signaling in living macrophages, we find that MyDDosomes assemble within minutes of TLR4 stimulation. TLR4/MD2 activation leads only to formation of TLR4/MD2 heterotetramers, but not oligomers, suggesting a stoichiometric mismatch between activated receptors and MyDDosomes. The strength of TLR4 signalling depends not only on the number and size of MyDDosomes formed but also how quickly these structures assemble. Activated TLR4, therefore, acts transiently nucleating assembly of MyDDosomes, a process that is uncoupled from receptor activation. These data explain how the oncogenic mutation of MyD88 (L265P) assembles MyDDosomes in the absence of receptor activation to cause constitutive activation of pro-survival NF-κB signalling.

Cells in the immune system have proteins at their surface that detect molecules produced by invading microbes. One of these proteins is Toll-like receptor 4, TLR4 for short. Once TLR4 is activated, the immune cells form MyDDosomes – intricate complexes made of many different proteins. These structures form a signal that mobilizes the cell to fight the infection. In particular, the complexes set up a chain of events that leads to a gene-regulating protein getting access to the cell’s DNA. There, the protein switches on genes which produce other proteins important for inflammation, one of the body’s most important tools to fight an infection.

The activation of TLR4 is thought to be an all-or-nothing mechanism: the receptors are either ‘on’ or ‘off’. However, different microbial molecules recognized by TLR4 trigger different levels of inflammation, ranging from mild to severe. It remained unclear how an all-or-none response from the frontline receptors could lead to a gradual response from the cell.

Here, Latty et al. compare what happens to TLR4, MyDDosomes and the gene-regulating proteins when living immune cells are stimulated by different doses of two microbial molecules. These agents are both recognized by TLR4, but they lead to different levels of inflammation.

The type of microbial molecule, or their concentration, does not change how TLR4 is activated. Two TLR4 proteins can loosely associate with each together to form a dimer. When they bind a microbial molecule, the dimer becomes more stable. This changes the shape of the TLR4 proteins, which in turn triggers the formation of a scaffold of MyDDosomes. More stable TLR4 dimers are formed when the cells is in contact with a microbial molecule that triggers a strong immune reaction, and possibly when its concentration is higher.

Crucially, the different microbial agents and their concentration levels modify how MyDDosomes assemble. By ‘tagging’ each protein in the complex with a fluorescent chemical, Latty et al. can follow its formation as it actually happens. When the cells are stimulated with microbial molecules that provoke a strong inflammation, the MyDDosomes may be bigger, in greater numbers, and form more quickly. In turn, under strong microbial activation, the gene-regulating protein that switches on the immune response genes goes to the DNA faster and in higher numbers. This suggests that the pace of assembly, the size and the number of MyDDosomes control the strength of the immune response.

TLR4 is involved in diseases such as cancer or Alzheimer’s disease, where the body has an incorrect inflammation response. Knowing in greater detail the cellular processes activated by TLR4 could help efforts to find new drug targets for these conditions.

Pharmacological Effect of Caulophyllum robustum on Collagen-Induced Arthritis and Regulation of Nitric Oxide, NF-κB, and Proinflammatory Cytokines In Vivo and In Vitro

Caulophyllum robustum Maxim (C. robustum) has commonly been used as traditional Chinese medicine for the treatment of rheumatic pain and rheumatoid arthritis (RA) in China. This paper first investigated the anti-inflammation effect of C. robustum extraction (CRME) on RAW264.7 cells stimulated by lipopolysaccharide (LPS) and gene expression levels of inflammatory factors. Moreover, we first evaluated the anti-RA effects of CRME using collagen-induced arthritis (CIA) in DBA/1J mice, and the incidence, clinical score, and joint histopathology were evaluated. The levels of IL-1, IL-6, TNF-α, and PGE2 inflammatory factors in sera of mice were detected by enzyme-linked immunosorbent assay. The expression of NF-κB p65 in the joint was tested by immune histochemical technique. The results showed that, compared with the model group, CRME significantly improved symptoms of the arthritis index, limb swelling, and histological findings by decreasing synovial membrane damage, the extent of inflammatory cell infiltration, and the expansion of capillaries in CIA mice. The results also showed that CRME can reduce the levels of IL-1, IL-6, TNF-α, and PGE2 and inhibit the expression of NF-κB p65. All these results indicated the anti-inflammatory efficacy of CRME as a novel botanical extraction for the treatment of RA.

Dual-specificity phosphatase 5 acts as an anti-inflammatory regulator by inhibiting the ERK and NF-κB signaling pathways

Although dual-specificity phosphatase 5 (DUSP5), which inactivates extracellular signal-regulated kinase (ERK), suppresses tumors in several types of cancer, its functional roles remain largely unknown. Here, we show that DUSP5 is induced during lipopolysaccharide (LPS)-mediated inflammation and inhibits nuclear factor-κB (NF-κB) activity. DUSP5 mRNA and protein expression increased transiently in LPS-stimulated RAW 264.7 cells and then returned to basal levels. DUSP5 overexpression in RAW 264.7 cells suppressed the production of pro-inflammatory tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), whereas knockdown of DUSP5 increased their expression. Investigation of two major inflammatory signaling pathways, mitogen-activated protein kinase (MAPK) and NF-κB, using activator protein-1 (AP-1) and NF-κB reporter plasmids, respectively, showed that NF-κB transcription activity was downregulated by DUSP5 in a phosphatase activity-independent manner whereas AP-1 activity was inhibited by DUSP5 phosphatase activity towards ERK,. Further investigation showed that DUSP5 directly interacts with transforming growth factor beta-activated kinase 1 (TAK1) and inhibitor of κB (IκB) kinases (IKKs) but not with IκBα. DUSP5 binding to IKKs interfered with the association of TAK1 with IKKs, suggesting that DUSP5 might act as a competitive inhibitor of TAK1-IKKs association. Therefore, we propose that DUSP5 negatively regulates ERK and NF-κB in a phosphatase activity-dependent and -independent manner, respectively.

Lipopolysaccharide suppresses IgE-mast cell-mediated reactions

BACKGROUND

Clinical and experimental analyses have identified a central role for IgE/FcεRI/mast cells in promoting IgE-mediated anaphylaxis. Recent data from human studies suggest that bacterial infections can alter susceptibility to anaphylaxis.

OBJECTIVE

We examined the effect of LPS exposure on the induction of IgE-mast cell (MC) mediated reactions in mice.

METHODS

C57BL/6 WT, tlr4-/- and IL10-/- mice were exposed to LPS, and serum cytokines (TNF and IL-10) were measured. Mice were subsequently treated with anti-IgE, and the symptoms of passive IgE-mediated anaphylaxis, MC activation, Ca2+ -mobilization and the expression of FcεRI on peritoneal MCs were quantitated.

RESULTS

We show that LPS exposure of C57BL/6 WT mice constraints IgE-MC-mediated reactions. LPS-induced suppression of IgE-MC-mediated responses was TLR-4-dependent and associated with increased systemic IL-10 levels, decreased surface expression of FcεRI on MCs and loss of sensitivity to IgE activation. Notably, LPS-induced desensitization of MCs was short term with MC sensitivity to IgE reconstituted within 48 hours, which was associated with recapitulation of FcεRI expression on the MCs. Mechanistic analyses revealed a requirement for IL-10 in LPS-mediated decrease in MC FcεRI surface expression.

CONCLUSIONS & CLINICAL RELEVANCE

Collectively, these studies suggest that LPS-induced IL-10 promotes the down-regulation of MC surface FcεRI expression and leads to desensitization of mice to IgE-mediated reactions. These studies indicate that targeting of the LPS-TLR-4-IL-10 pathway may be used as a therapeutic approach to prevent adverse IgE-mediated reactions.

Impact of Chronic Stress on the Spatial Learning and GR-PKAc-NF-κB Signaling in the Hippocampus and Cortex in Rats Following Cholinergic Depletion

Studies have shown that the removal of the cholinergic innervation to the hippocampus induces dysfunction of the hypothalamic-pituitary-adrenocortical axis and decreases the number of glucocorticoid receptors (GRs). Subsequent studies have revealed that the loss of cholinergic input to the hippocampus reduces the expression of GRs and activates nuclear factor-kappa B (NF-κB) signaling through interactions with the cytoplasmic catalytic subunit of protein kinase A (PKAc). We examined the effects of chronic stress on cognitive status and GR-PKAc-NF-κB signaling in rats with a loss of cholinergic input to the hippocampus and cortex. Male Sprague-Dawley rats received 192 IgG-saporin injections to selectively eliminate cholinergic neurons in their basal forebrain. Two weeks later, rats were subjected to 1 h of restraint stress per day for 14 days. Rats subjected to both chronic stress and cholinergic depletion showed more severe memory impairments compared to those that received either treatment alone. The reduction in nuclear GR levels induced by cholinergic depletion was unaffected by chronic stress. The activation of NF-κB signaling in the hippocampus and the cerebral cortex induced by cholinergic depletion was augmented by chronic stress, resulting in the increased expression of pro-inflammatory markers, such as inducible nitric oxide synthase and cyclooxygenase-2. The activation of NF-κB induced by cholinergic depletion appears to be aggravated by chronic stress, and this might explain the increased susceptibility of patients with Alzheimer's disease to stress since activation of NF-κB is associated with stress.

Salmeterol, a Long-Acting β2-Adrenergic Receptor Agonist, Inhibits Macrophage Activation by Lipopolysaccharide From Porphyromonas gingivalis

BACKGROUND

Salmeterol is a long-acting β2-adrenergic receptor agonist used to treat chronic obstructive pulmonary disease. The authors of the current study previously showed that preincubation of primary microglial-enriched cells with salmeterol could inhibit the inflammatory response induced by Escherichia coli lipopolysaccharide (LPS), a Toll-like receptor (TLR)-4 agonist. In this study, the authors sought to determine if salmeterol had a similar inhibitory effect on the inflammatory response of the murine macrophage cell line RAW264.7 and human monocyte THP-1 to LPS from Porphyromonas gingivalis (PgLPS), an oral microbe implicated in the pathogenesis of periodontal disease.

METHODS

RAW264.7 and THP-1 cells were pretreated with salmeterol, followed by PgLPS, and monitored for production of inflammatory mediators by enzyme-linked immunosorbent assay. The nitric oxide concentration and nuclear factor-kappa B (NF-κB) activity were measured by Griess method and secretory alkaline phosphatase reporter activity assay, respectively. Reverse-transcriptase polymerase chain reaction and immunoblot analysis were used to measure messenger RNA and protein levels. Nuclear translocation of NF-κB was detected by immunofluorescence.

RESULTS

Pretreatment with salmeterol significantly inhibited production of proinflammatory mediators by RAW264.7 and THP-1 cells. Salmeterol downregulated PgLPS-mediated phosphorylation of the extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase but not p38 mitogen-activated protein kinases (MAPKs). Salmeterol also attenuated activation of NF-κB via inhibition of nuclear translocation of p65-NFκB, the transcriptional activity of NF-κB and IκBα phosphorylation.

CONCLUSION

Salmeterol can significantly inhibit activation of macrophage-mediated inflammation by PgLPS, suggesting that use of salmeterol may be an effective treatment in inhibiting or lessening the inflammatory response mediated through TLR pathway activation.

Myeloid-derived NF-κB negative regulation of PU.1 and c/EBP-β-driven pro-inflammatory cytokine production restrains LPS-induced shock

Sepsis is a life-threatening event predominantly caused by Gram-negative bacteria. Bacterial infection causes a pronounced macrophage (MΦ) and dendritic cell activation that leads to excessive pro-inflammatory cytokine IL-1β, IL-6 and TNF-α production (cytokine storm), resulting in endotoxic shock. Previous experimental studies have revealed that inhibiting NF-κB signaling ameliorates disease symptoms; however, the contribution of myeloid p65 in endotoxic shock remains elusive. In this study, we demonstrate increased mortality in mice lacking p65 in the myeloid lineage (p65Δmye) compared with wild type mice upon ultra-pure LPS challenge. We show that increased susceptibility to LPS-induced shock was associated with elevated serum level of IL-1β and IL-6. Mechanistic analyses revealed that LPS-induced pro-inflammatory cytokine production was ameliorated in p65-deficient bone marrow-derived MΦs; however, p65-deficient 'activated' peritoneal MΦs exhibited elevated IL-1β and IL-6. We show that the elevated pro-inflammatory cytokine secretion was due, in part, to increased accumulation of IL-1β mRNA and protein in activated inflammatory MΦs. The increased IL-1β was linked with heightened binding of PU.1 and CCAAT/enhancer binding protein-β to Il1b and Il6 promoters in activated inflammatory MΦs. Our data provide insight into a role for NF-κB in the negative regulation of pro-inflammatory cytokines in myeloid cells.

Hyperglycemia and high nitric oxide level induced oxidative stress in the brain and molecular alteration in the neurons and glial cells of laboratory mouse, Mus musculus

Chronic hyperglycemia (glucotoxicity) is reported to have detrimental effects on various brain functions leading to neurodegenerative changes. However, the effect of hyperglycemia in combination with high nitric oxide (NO) level (reported to be increased during glucotoxicity), on brain functions is not clear yet. The present study was designed to investigate the effects of hyperglycemic drug Streptozotocin (STZ) and NO donor Sodium nitroprusside (SNP) on the brain of laboratory mouse, Mus musculus. Effects of these conditions were studied on the markers of oxidative stress, NF-κB signalling and the markers of neuronal and glial cell activation/inflammation. Results indicate increased level of MDA and altered antioxidant enzymes activity in both the treated groups compared to control but high levels of AGEs, AOPP and AR activity (markers of diabetic complications) were observed in STZ group only. On the other hand, while STZ group showed decreased IL-6 level, it was increased in SNP group but IFN-ϒ level increased in both the treated groups compared to control. Further, in addition to alterations in the expressions of iNOS, IKKβ, IKBα and NF-κB subunits (RelA-p65/RelB-p50) observed in the neurons and glial cells of different brain regions (hypothalamus, basolateral amygdala and cerebral cortex), enhanced expression of microglial CD11b and astrocytic GFAP was also found in both the treated groups compared to control. Present findings led us to conclude that both hyperglycemia and high NO level causes oxidative stress in addition to molecular alteration in the neurons and glial cells. It is suggested that high blood glucose and NO level induced oxidative stress may lead to neuroinflammation possibly via NF-κB signalling.

The NF-κB p65/miR-23a-27a-24 cluster is a target for leukemia treatment

p65 is a transcription factor that is involved in many physiological and pathologic processes. Here we report that p65 strongly binds to the miR-23a-27a-24 cluster promoter to up-regulate its expression. As bone marrow-derived cells differentiate into red blood cells in vitro, p65/miR-23a-27a-24 cluster expression increases sharply and then declines before the appearance of red blood cells, suggesting that this cluster is negatively related to erythroid terminal differentiation. Bioinformatic and molecular biology experiments confirmed that the miR-23a-27a-24 cluster inhibited the expression of the erythroid proteome and contributed to erythroleukemia progression. In addition, high level of the p65/miR-23a-27a-24 cluster was found in APL and AML cell lines and in nucleated peripheral blood cells from leukemia patients. Furthermore, anti-leukemia drugs significantly inhibited the expression of the p65/miR-23a-27a-24 cluster in leukemia cells. Administration of the p65 inhibitor parthenolide significantly improved hematology and myelogram indices while prolonging the life span of erythroleukemia mice. Meanwhile, stable overexpression of these three miRNAs in mouse erythroleukemia cells enhanced cell malignancy. Our findings thus connect a novel regulation pathway of the p65/miR-23a-27a-24 cluster with the erythroid proteome and provide an applicable approach for treating leukemia.

Loss of the oncogenic phosphatase PRL-3 promotes a TNF-R1 feedback loop that mediates triple-negative breast cancer growth

Stimulating tumor cell senescence and apoptosis are proven methods for therapeutically combating cancer. However, senescence and apoptosis are conventionally viewed as parallel, not sequential, processes. We have discovered that the metastasis-promoting phosphatase, PRL-3, is transcriptionally regulated by the NF-ĸB pathway in triple-negative breast cancer (TNBC) cells, and that PRL-3 knockdown elicits an autocrine tumor necrosis factor receptor 1 (TNF-R1) feedback loop that results in TNBC cell senescence followed by apoptosis. Knockdown of PRL-3 leads to rapid G1 cell cycle arrest and induction of a strong TNFα cytokine response that promotes a period of cellular senescence through TNF-R1-mediated activation of NF-ĸB. Senescent PRL-3 knockdown cells subsequently underwent apoptosis as a result of increased TNF-R1 signaling through the TNFα-associated extrinsic death pathway, shunting signaling away from the NF-ĸB cascade. These data suggest that TNF-R1 signaling dynamically re-programs after PRL-3 knockdown, from sustaining cell senescence through NF-ĸB to promoting apoptosis through TNF-R1 internalization and caspase-8 activation. The molecular mechanisms that determine the survival–death balance of TNF-R1 signaling are poorly understood, despite the fact that TNF-R1 has been extensively studied. Our results describe PRL-3 knockdown as a novel survival–death balance modifier of the TNF-R1 pathway, and show that senescent TNBC tumor cells can be sensitized to undergo apoptosis in a sequential manner.

BaeR protein acts as an activator of nuclear factor-kappa B and Janus kinase 2 to induce inflammation in murine cell lines

BaeR, a response regulator protein, takes part in multidrug efflux, bacterial virulence activity, and other biological functions. Recently, BaeR was shown to induce inflammatory responses by activating the mitogen-activated protein kinases (MAPKs). In this study, we investigated additional pathways used by BaeR to induce an inflammatory response. BaeR protein was purified from Salmonella enterica Paratyphi A and subcloned into a pPosKJ expression vector. RAW 264.7 cells were treated with BaeR, and RNA was extracted by TRIzol reagent for RT-PCR. Cytokine gene expression was analyzed by using the comparative cycle threshold method, while western blotting and ELISA were used to assess protein expression. We confirmed that BaeR activates nuclear factor-kappa B (NF-κB), thereby inducing an inflammatory response and increases the production of interleukins (IL-)1β and IL-6. During this process, the Janus kinase 2 (JAK2)-STAT1 signaling pathway was activated, resulting in an increase in the release of interferons I and II. Additionally, COX-2 was activated and its expression increased with time. In conclusion, BaeR induced an inflammatory response through activation of NF-κB in addition to the MAPKs. Furthermore, activation of the JAK2-STAT1 pathway and COX-2 facilitated the cytokine binding activity, suggesting an additional role for BaeR in the modulation of the immune system of the host and the virulence activity of the pathogen.

Progranulin deficiency induces overactivation of WNT5A expression via TNF-α/NF-κB pathway in peripheral cells from frontotemporal dementia-linked granulin mutation carriers

BACKGROUND

Loss-of-function progranulin gene (GRN) mutations have been identified as the major cause of frontotemporal lobar degeneration with transactive response (TAR) DNA-binding protein 43 (TDP-43) pathology (frontotemporal lobar degeneration [FTLD]-TDP); however, little is known about the association between progranulin (PGRN) deficiency and neuronal loss in individuals with FTLD-TDP. Previously we reported enhanced proliferative activity associated with the activation of WNT5A/CDK6/pRb signalling in PGRN-deficient cells. The objective of this work was to elucidate the association between PGRN deficiency, WNT5A signalling and cell proliferation in immortalized lymphoblasts from carriers of the c.709-1G > A GRN mutation (asymptomatic and FTLD-TDP).

METHODS

We assessed cell proliferation in carriers of the c.709-1G > A GRN gene mutation and controls without GRN mutation and without sign of neurologic degeneration by cell counting or using an MTT assay. We used a luciferase assay to measure the nuclear factor-κ (NF-κ) activity. We evaluated messenger RNA levels using quantitative real-time polymerase chain reaction and protein levels by immunoblotting. Co-immunoprecipitation was used to analyze the interaction between PGRN and its receptors.

RESULTS

We enrolled 19 carriers of the GRN gene mutation and 10 controls in this study. The PGRN-deficient cells showed increased expression of WNT5A due to NF-κB signalling overactivation. We observed a competition between PGRN and tumour necrosis factor-α (TNF-α) for binding both TNF receptors (TNFR) I and II. Blocking NF-κB signalling using wedelolactone or specific antibodies against TNFRs inhibited WNT5A overexpression and proliferation of PGRN-deficient cells. Conversely, the activation of NF-κB signalling by TNF-α increased WNT5A-dependent proliferation of control cells.

LIMITATIONS

All cell lines were derived from individuals harboring the same splicing GRN mutation. Nevertheless, most of the known GRN mutations lead to haploinsufficiency of the protein.

CONCLUSION

Our results revealed an important role of NF-κB signalling in PGRN-associated FTLD-TDP and confirm that PGRN can bind to TNF-α receptors regulating the expression of WNT5A, suggesting novel targets for treatment of FTLD-TDP linked to GRN mutations.

Ctenopharyngodon idella NF-κB subunit p65 modulates the transcription of IκBα in CIK cells

NF-κB is an important transcription factor for regulating the multiple inflammatory and immune related gene transcription. It can bind with the nuclear factor κB site within the promoter of target genes to regulate their transcriptions. p65, the all-important subunit of NF-κB, is ubiquitously expressed in cells. In the present study, we cloned and identified the p65 subunit from grass carp (Ctenopharyngodon idella) (named Cip65) by homologous cloning and RACE technique. The full length of Cip65 cDNA is 2481 bp along with 9 bp 5' UTR, 639 bp 3' UTR and the largest open reading frame (1833 bp) encoding a polypeptide of 610 amino acids with a well conserved Rel-homology domain (RHD) in N-terminal and a putative transcription activation domain (TAD) in C-terminal. Cip65 gathers with other teleost p65 proteins to form a fish-specific clade clearly distinct from those of mammalian and amphibian counterparts on the phylogenetic tree. In CIK (C. idellus kidney) cells, the expression of Cip65 was significantly up-regulated under the stimulation with Poly I:C. As one member of the NF-κB inhibitor protein (IκB) family, IκBα can dominate the activity of NF-κB by interacting with it. To study the molecular mechanisms of negative feedback loop of NF-κB signaling in fish, we cloned grass carp IκBα (CiIκBα) promoter sequence. CiIκBα promoter is 414 bp in length containing two RelA binding sites and a putative atypical TATA-box. Meanwhile, Cip65 and its mutant proteins including C-terminus deletion mutant of Cip65 (Cip65-ΔC) and N-terminus deletion mutant of Cip65 (Cip65-ΔN) were expressed in Escherichia coli BL21 and purified by affinity chromatography with the Ni-NTA His-Bind resin. In vitro, Cip65 rather than Cip65-ΔC and Cip65-ΔN showed high affinity with CiIκBα promoter sequence by gel mobility shift assays. In vivo, the cotransfection of pcDNA3.1-Cip65 (or pcDNA3.1-Cip65-ΔC, pcDNA3.1-Cip65-ΔN respectively) with pGL3-CiIκBα and pRL-TK renilla luciferase plasmid into CIK cells showed that pcDNA3.1-Cip65 rather than pcDNA3.1-Cip65-ΔC and pcDNA3.1-Cip65-ΔN, can increase the luciferase activity. Taken together, these results suggested that Cip65 can regulate the expression of CiIκBα and works as a negative feedback loop in NF-κB pathway.

The linear structure of β-glucan from baker's yeast and its activation of macrophage-like RAW264.7 cells

Yeast β-glucan has many formulations with different chemical structures, water solubility and purity. In particular, the purity of β-glucan in these formulations is variable and relatively low, contributing to different data on its biological activity. In this study, the major polysaccharide component in the crude Baker's yeast polysaccharides coded as BBG with high purity of 99% was obtained, and its chemical structure was determined to be a linear β-(1,3)-glucan. It was found that BBG interacted with complement receptor 3 (CR3) and toll-like receptor 2 (TLR2) on the surface of macrophage-like RAW264.7 cells, and initiated activation of RAW264.7 cells characterized by significant production of tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein 1 (MCP-1). Additionally, activation of the nuclear factor kappaB p65 (NF-κB p65), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) induced by BBG, were also observed, further confirming the stimulation of RAW264.7 cells by BBG. All these findings provided important scientific evidences for better understanding the molecular mechanism of action for the linear β-(1,3)-glucan in cells.

Group A Streptococcus induces less p65 nuclear translocation and non-classical nuclear factor kappa B activation in macrophages, which possibly leads to a weaker inflammatory response

OBJECTIVES

The aim of this study was to explore the pathogenic mechanism of group A Streptococcus (GAS) and to investigate how GAS evades phagocytosis by immune cells.

METHODS

The classical inflammatory signaling pathway of macrophages infected with GAS was investigated by protein microarray, real-time PCR, Western blot, immunoprecipitation, and flow cytometry.

RESULTS

GAS induced a lower level of inflammatory mediators in macrophages than either the Gram-positive Staphylococcus aureus or the Gram-negative Escherichia coli. Therefore, the conventional inflammatory signal pathway was investigated. It was found that GAS and S. aureus induced both toll-like receptor (TLR)2 and TLR4 expression, while Gram-negative E. coli only activated TLR4 in RAW264.7 cells. Although MyD88, the main adaptor protein, was activated by the three pathogens, there was no difference in MyD88 expression in macrophages. Nuclear factor kappa B (NF-κB) is the classical transcription factor of inflammatory signals, and the results of the present study showed that GAS, similar to E. coli, induced a weaker p65 nuclear translocation compared to S. aureus. Interestingly, GAS activated NF-κB by inducing p65-p52 heterodimer, but not the classical heterodimer of NF-κB (p65-p50), while E. coli activated NF-κB by inducing both p65-p50 and p65-p52 heterodimers.

CONCLUSIONS

Compared to S. aureus and E. coli infection, GAS induced a weaker nuclear translocation and distinct combination of NF-κB subunits in macrophages, which probably leads to a weak inflammatory response.

Gualou Xiebai decoction inhibits cardiac dysfunction and inflammation in cardiac fibrosis rats

Background

Gualou Xiebai Decoction (GXD) is a well-known traditional Chinese recipe. It has been used to treat cardiovascular disorders for nearly two thousand years. But there is a lack of reports on cardiac fibrosis and underlying mechanism.

Methods

Myocardial infarction was performed by ligation of left anterior descending coronary artery (LAD) in male Wistar rats. Rats with myocardial infarction were treated with GXD (1.14 g/kg, 4.53 g/kg) daily for 4 weeks. Cardiac function was evaluated by echocardiography. Hemodynamic parameters and infarct size were measured in each group. Myocardial enzymes were examined by biochemical tests. Inflammatory cytokines were assessed by ELISA, and interrelated proteins were detected by western blot.

Results

Cardiac function was significantly improved in GXD-treatment rats after myocardial infarction (MI), which was accompanied with decreased infarct size. Administration of GXD to myocardial fibrosis rats significantly ameliorated the activities of AST, LDH and CK-MB in serum. The increase in inflammatory factors (TNF-α, IL-1β) were markedly reduced upon GXD treatment. Furthermore, the inflammatory mediators (NF-κB p65, TNF-α, MCP-1) were down-regulated by GXD in the myocardial fibrosis rats.

Conclusions

Treatment with GXD improved cardiac function induced by myocardial fibrosis by inhibiting expression of inflammatory mediators associated with NF-κB.