scholarly journals The Role of Flagellin B in Vibrio anguillarum-Induced Intestinal Immunity and Functional Domain Identification

2021 ◽  
Vol 12 ◽  
Author(s):  
Quanxin Gao ◽  
Shaokui Yi ◽  
Yang Li ◽  
Jinping Luo ◽  
Qianqian Xing ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Vibrio Anguillarum ◽  
Acid Sites ◽  
Functional Domain ◽  
Intestinal Immunity ◽  
Native Page ◽  
Domain Identification ◽  
Tlr5 Expression

Vibrio anguillarum, an opportunistic pathogen of aquatic animals, moves using a filament comprised of polymerised flagellin proteins. Flagellins are essential virulence factors for V. anguillarum infection. Herein, we investigated the effects of flagellins (flaA, flaB, flaC, flaD and flaE) on cell apoptosis, TLR5 expression, and production of IL-8 and TNF-α. FlaB exhibited the strongest immunostimulation effects. To explore the functions of flaB in infection, we constructed a flaB deletion mutant using a two-step recombination method, and in vitro experiments showed a significant decrease in the expression of TLR5 and inflammatory cytokines compared with wild-type cells. However in the in vivo study, expression of inflammatory cytokines and intestinal mucosal structure showed no significant differences between groups. Additionally, flaB induced a significant increase in TLR5 expression based on microscopy analysis of fluorescently labelled TLR5, indicating interactions between the two proteins, which was confirmed by native PAGE and yeast two-hybrid assay. Molecular simulation of interactions between flaB and TLR5 was performed to identify the residues involved in binding, revealing two binding sites. Then, based on molecular dynamics simulations, we carried out thirteen site-directed mutations occurring at the amino acid sites of Q57, N83, N87, R91, D94, E122, D152, N312, R313, N320, L97, H316, I324 in binding regions of flaB protein by TLR5, respectively. Surface plasmon resonance (SPR) was employed to compare the affinities of flaB mutants for TLR5, and D152, D94, I324, N87, R313, N320 and H316 were found to mediate interactions between flaB and TLR5. Our comprehensive and systematic analysis of V. anguillarum flagellins establishes the groundwork for future design of flagellin-based vaccines.

Methylmercury-induced pro-inflammatory cytokines activation and its preventive strategy using anti-inflammation N-acetyl-l-cysteine: a mini-review

2020 ◽  
Vol 35 (3) ◽  
pp. 233-238
Author(s):  
Muflihatul Muniroh
Keyword(s):  
Inflammatory Cytokines ◽  
Health Concern ◽  
Brain Cells ◽  
Preventive Strategy ◽  
Hearing Impairments ◽  
Sensory Disturbances ◽  
Anti Inflammation ◽  
Pro Inflammatory Cytokines

AbstractThe exposure of methylmercury (MeHg) has become a public health concern because of its neurotoxic effect. Various neurological symptoms were detected in Minamata disease patients, who got intoxicated by MeHg, including paresthesia, ataxia, gait disturbance, sensory disturbances, tremors, visual, and hearing impairments, indicating that MeHg could pass the blood-brain barrier (BBB) and cause impairment of neurons and other brain cells. Previous studies have reported some expected mechanisms of MeHg-induced neurotoxicity including the neuroinflammation pathway. It was characterized by the up-regulation of numerous pro-inflammatory cytokines expression. Therefore, the use of anti-inflammatories such as N-acetyl-l-cysteine (NAC) may act as a preventive compound to protect the brain from MeHg harmful effects. This mini-review will explain detailed information on MeHg-induced pro-inflammatory cytokines activation as well as possible preventive strategies using anti-inflammation NAC to protect brain cells, particularly in in vivo and in vitro studies.

scholarly journals N-palmitoyl-D-glucosamine, A Natural Monosaccharide-Based Glycolipid, Inhibits TLR4 and Prevents LPS-Induced Inflammation and Neuropathic Pain in Mice

2021 ◽  
Vol 22 (3) ◽  
pp. 1491 ◽  
Author(s):  
Monica Iannotta ◽  
Carmela Belardo ◽  
Maria Consiglia Trotta ◽  
Fabio Arturo Iannotti ◽  
Rosa Maria Vitale ◽  
...  
Keyword(s):  
Sciatic Nerve ◽  
Inflammatory Cytokines ◽  
Lipid A ◽  
Saturated Fatty Acids ◽  
Structural Similarity ◽  
Antagonistic Activity ◽  
Critical Function ◽  
Anti Inflammatory

Toll-like receptors (TLRs) are key receptors through which infectious and non-infectious challenges act with consequent activation of the inflammatory cascade that plays a critical function in various acute and chronic diseases, behaving as amplification and chronicization factors of the inflammatory response. Previous studies have shown that synthetic analogues of lipid A based on glucosamine with few chains of unsaturated and saturated fatty acids, bind MD-2 and inhibit TLR4 receptors. These synthetic compounds showed antagonistic activity against TLR4 activation in vitro by LPS, but little or no activity in vivo. This study aimed to show the potential use of N-palmitoyl-D-glucosamine (PGA), a bacterial molecule with structural similarity to the lipid A component of LPS, which could be useful for preventing LPS-induced tissue damage or even peripheral neuropathies. Molecular docking and molecular dynamics simulations showed that PGA stably binds MD-2 with a MD-2/(PGA)3 stoichiometry. Treatment with PGA resulted in the following effects: (i) it prevented the NF-kB activation in LPS stimulated RAW264.7 cells; (ii) it decreased LPS-induced keratitis and corneal pro-inflammatory cytokines, whilst increasing anti-inflammatory cytokines; (iii) it normalized LPS-induced miR-20a-5p and miR-106a-5p upregulation and increased miR-27a-3p levels in the inflamed corneas; (iv) it decreased allodynia in peripheral neuropathy induced by oxaliplatin or formalin, but not following spared nerve injury of the sciatic nerve (SNI); (v) it prevented the formalin- or oxaliplatin-induced myelino-axonal degeneration of sciatic nerve. SIGNIFICANCE STATEMENT We report that PGA acts as a TLR4 antagonist and this may be the basis of its potent anti-inflammatory activity. Being unique because of its potency and stability, as compared to other similar congeners, PGA can represent a tool for the optimization of new TLR4 modulating drugs directed against the cytokine storm and the chronization of inflammation.

scholarly journals Reductions of copper ion-mediated low-density lipoprotein (LDL) oxidations of trypsin inhibitors, the sweet potato root major proteins, and LDL binding capacities

2020 ◽  
Vol 61 (1) ◽  
Author(s):  
Yeh-Lin Lu ◽  
Chia-Jung Lee ◽  
Shyr-Yi Lin ◽  
Wen-Chi Hou
Keyword(s):  
Sweet Potato ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Trypsin Inhibitors ◽  
Water Soluble ◽  
Affinity Column ◽  
Low Density ◽  
Native Page

Abstract Background The root major proteins of sweet potato trypsin inhibitors (SPTIs) or named sporamin, estimated for 60 to 80% water-soluble proteins, exhibited many biological activities. The human low-density lipoprotein (LDL) showed to form in vivo complex with endogenous oxidized alpha-1-antitrypsin. Little is known concerning the interactions between SPTIs and LDL in vitro. Results The thiobarbituric-acid-reactive-substance (TBARS) assays were used to monitor 0.1 mM Cu2+-mediated low-density lipoprotein (LDL) oxidations during 24-h reactions with or without SPTIs additions. The protein stains in native PAGE gels were used to identify the bindings between native or reduced forms of SPTIs or soybean TIs and LDL, or oxidized LDL (oxLDL). It was found that the SPTIs additions showed to reduce LDL oxidations in the first 6-h and then gradually decreased the capacities of anti-LDL oxidations. The protein stains in native PAGE gels showed more intense LDL bands in the presence of SPTIs, and 0.5-h and 1-h reached the highest one. The SPTIs also bound to the oxLDL, and low pH condition (pH 2.0) might break the interactions revealed by HPLC. The LDL or oxLDL adsorbed onto self-prepared SPTIs-affinity column and some components were eluted by 0.2 M KCl (pH 2.0). The native or reduced SPTIs or soybean TIs showed different binding capacities toward LDL and oxLDL in vitro. Conclusion The SPTIs might be useful in developing functional foods as antioxidant and nutrient supplements, and the physiological roles of SPTIs-LDL and SPTIs-oxLDL complex in vivo will investigate further using animal models.

scholarly journals Porcine Milk-Derived Small Extracellular Vesicles Promote Intestinal Immunoglobulin Production through pIgR

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1522
Author(s):  
Bin Zeng ◽  
Hailong Wang ◽  
Junyi Luo ◽  
Meiying Xie ◽  
Zhengjiang Zhao ◽  
...  
Keyword(s):  
Small Intestine ◽  
Extracellular Vesicles ◽  
Immunoglobulin A ◽  
Luciferase Reporter ◽  
Epithelial Cell Line ◽  
Intestinal Immunity ◽  
In Vivo Experiments ◽  
Porcine Milk

Secretory immunoglobulin A (SIgA) plays an important role in gut acquired immunity and mucosal homeostasis. Breast milk is the irreplaceable nutritional source for mammals after birth. Current studies have shown the potential functional role of milk-derived small extracellular vesicles (sEVs) and their RNAs cargo in intestinal health and immune regulation. However, there is a lack of studies to demonstrate how milk-derived sEVs affect intestinal immunity in recipient. In this study, through in vivo experiments, we found that porcine milk small extracellular vesicles (PM-sEVs) promoted intestinal SIgA levels, and increased the expression levels of polymeric immunoglobulin receptor (pIgR) both in mice and piglet. We examined the mechanism of how PM-sEVs increased the expression level of pIgR in vitro by using a porcine small intestine epithelial cell line (IPEC-J2). Through bioinformatics analysis, dual-luciferase reporter assays, and overexpression or knockdown of the corresponding non-coding RNAs, we identified circ-XPO4 in PM-sEVs as a crucial circRNA, which leads to the expression of pIgR via the suppression of miR-221-5p in intestinal cells. Importantly, we also observed that oral administration of PM-sEVs increased the level of circ-XPO4 and decreased the level of miR-221-5p in small intestine of piglets, indicating that circRNAs in milk-derived sEVs act as sponge for miRNAs in recipients. This study, for the first time, reveals that PM-sEVs have a capacity to stimulate intestinal SIgA production by delivering circRNAs to receptors and sponging the recipient’s original miRNAs, and also provides valuable data for insight into the role and mechanism of animal milk sEVs in intestinal immunity.

scholarly journals Macrophage-Biomimetic Porous Se@SiO2 Nanocomposites For “Dual Model” Immunotherapy Against Inflammatory Osteolysis

2021 ◽  
Author(s):  
Cheng Ding ◽  
Chuang Yang ◽  
Tao Cheng ◽  
Xingyan Wang ◽  
Qiaojie Wang ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Total Joint Replacement ◽  
Major Complication ◽  
Dual Model ◽  
Joint Replacement Surgery ◽  
Pro Inflammatory Cytokines ◽  
Macrophage Membrane

Abstract Background：Inflammatory osteolysis is a major complication of total joint replacement surgery that can cause prosthesis failure and necessitate revision surgery. Macrophages are key effector immune cells in inflammatory responses, but excessive M1-polarization of dysfunctional macrophages leads to the secretion of pro-inflammatory cytokines and severe loss of bone tissue. Here, we report the development of macrophage-biomimetic porous SiO2-coated ultrasmall Se particles (Porous Se@SiO2 nanospheres) for the management of inflammatory osteolysis. Results: Macrophage-membrane-coated porous Se@SiO2 nanospheres(M-Se@SiO2) can attenuate lipopolysaccharide (LPS)-induced inflammatory osteolysis by a dual-immunomodulatory effect. As macrophage membrane decoys, these nanoparticles reduce toxin levels and neutralize pro-inflammatory cytokines. Moreover, the release of Se can induce the polarization of macrophages toward the anti-inflammatory M2-phenotype. These effects are mediated via the inhibition of p65, p38, and extracellular signal-regulated kinase(ERK) signaling. Additionally, the immune environment created by M-Se@SiO2 reduces the inhibition of osteogenic differentiation caused by pro-inflammation cytokines, confirmed through in vitro and in vivo experiments.Conclusion: Our findings suggest that M-Se@SiO2 has an immunomodulatory role in LPS-induced inflammation and bone remodeling, which demonstrates that M-Se@SiO2 is a promising engineered nano-platform for the treatment of osteolysis arising after arthroplasty.

scholarly journals Extracellular vesicles from human cardiovascular progenitors trigger a reparative immune response in infarcted hearts

2020 ◽  
Author(s):  
Bruna Lima Correa ◽  
Nadia El Harane ◽  
Ingrid Gomez ◽  
Hocine Rachid Hocine ◽  
José Vilar ◽  
...  
Keyword(s):  
Immune Response ◽  
Extracellular Vesicles ◽  
Inflammatory Cytokines ◽  
Nk Cell ◽  
Inflammatory Monocytes ◽  
Ifn Γ ◽  
Anti Inflammatory ◽  
Pro Inflammatory Cytokines

Abstract Aims The cardioprotective effects of human induced pluripotent stem cell-derived cardiovascular progenitor cells (CPC) are largely mediated by the paracrine release of extracellular vesicles (EV). We aimed to assess the immunological behaviour of EV-CPC, which is a prerequisite for their clinical translation. Methods and results Flow cytometry demonstrated that EV-CPC expressed very low levels of immune relevant molecules including HLA Class I, CD80, CD274 (PD-L1), and CD275 (ICOS-L); and moderate levels of ligands of the natural killer (NK) cell activating receptor, NKG2D. In mixed lymphocyte reactions, EV-CPC neither induced nor modulated adaptive allogeneic T cell immune responses. They also failed to induce NK cell degranulation, even at high concentrations. These in vitro effects were confirmed in vivo as repeated injections of EV-CPC did not stimulate production of immunoglobulins or affect the interferon (IFN)-γ responses from primed splenocytes. In a mouse model of chronic heart failure, intra-myocardial injections of EV-CPC, 3 weeks after myocardial infarction, decreased both the number of cardiac pro-inflammatory Ly6Chigh monocytes and circulating levels of pro-inflammatory cytokines (IL-1α, TNF-α, and IFN-γ). In a model of acute infarction, direct cardiac injection of EV-CPC 2 days after infarction reduced pro-inflammatory macrophages, Ly6Chigh monocytes, and neutrophils in heart tissue as compared to controls. EV-CPC also reduced levels of pro-inflammatory cytokines IL-1α, IL-2, and IL-6, and increased levels of the anti-inflammatory cytokine IL-10. These effects on human macrophages and monocytes were reproduced in vitro; EV-CPC reduced the number of pro-inflammatory monocytes and M1 macrophages, while increasing the number of anti-inflammatory M2 macrophages. Conclusions EV-CPC do not trigger an immune response either in in vitro human allogeneic models or in immunocompetent animal models. The capacity for orienting the response of monocyte/macrophages towards resolution of inflammation strengthens the clinical attractiveness of EV-CPC as an acellular therapy for cardiac repair.

scholarly journals HDAC2 attenuates airway inflammation by suppressing IL-17A production in HDM-challenged mice

2019 ◽  
Vol 316 (1) ◽  
pp. L269-L279 ◽  
Author(s):  
Tianwen Lai ◽  
Mindan Wu ◽  
Chao Zhang ◽  
Luanqing Che ◽  
Feng Xu ◽  
...  
Keyword(s):  
Airway Inflammation ◽  
Inflammatory Cytokines ◽  
Allergic Inflammation ◽  
Allergic Airway Inflammation ◽  
Inflammatory Cells ◽  
Protective Role ◽  
In Vivo Models

Histone deacetylase (HDAC)2 is expressed in airway epithelium and plays a pivotal role in inflammatory cells. However, the role of HDAC2 in allergic airway inflammation remains poorly understood. In the present study, we determined the role of HDAC2 in airway inflammation using in vivo models of house dust mite (HDM)-induced allergic inflammation and in vitro cultures of human bronchial epithelial (HBE) cells exposed to HDM, IL-17A, or both. We observed that HDM-challenged Hdac2+/− mice exhibited substantially enhanced infiltration of inflammatory cells. Higher levels of T helper 2 cytokines and IL-17A expression were found in lung tissues of HDM-challenged Hdac2+/− mice. Interestingly, IL-17A deletion or anti-IL-17A treatment reversed the enhanced airway inflammation induced by HDAC2 impairment. In vitro, HDM and IL-17A synergistically decreased HDAC2 expression in HBE cells. HDAC2 gene silencing further enhanced HDM- and/or IL-17A-induced inflammatory cytokines in HBE cells. HDAC2 overexpresion or blocking IL-17A gene expression restored the enhanced inflammatory cytokines. Collectively, these results support a protective role of HDAC2 in HDM-induced airway inflammation by suppressing IL-17A production and might suggest that activation of HDAC2 and/or inhibition of IL-17A production could prevent the development of allergic airway inflammation.

Identification of the functional domain of p21WAF1/CIP1 that protects cells from cisplatin cytotoxicity

2005 ◽  
Vol 289 (3) ◽  
pp. F514-F520 ◽  
Author(s):  
Fang Yu ◽  
Judit Megyesi ◽  
Robert L. Safirstein ◽  
Peter M. Price
Keyword(s):  
Dominant Negative ◽  
Nuclear Antigen ◽  
Functional Domain ◽  
Binding Domains ◽  
Cdk2 Activity ◽  
Localization Signal ◽  
Induced Apoptosis ◽  
Proliferating Cell

The p21 cyclin-dependent kinase (cdk) inhibitor protects cells from cisplatin cytotoxicity in vivo and in vitro. However, the mechanism of protection is not known. Separate p21 domains are known to interact with several different proteins having proapoptotic functions. To investigate the mechanism of protection by p21, we have constructed adenoviruses encoding the different domains of p21. We were able to localize the protective activity to a region of 54 amino acids containing the cyclin-cdk interacting moiety. Other protein binding domains of p21, including the NH2-terminal procaspase-3 interactive region and the COOH-terminal region containing the proliferating cell nuclear antigen binding domain and the nuclear localization signal, had little protective effect on cisplatin cytotoxicity. The dependence of cisplatin cytotoxicity on cdk2 activity was also demonstrated because 1) cisplatin caused a marked increase in cdk2 activity, which was prevented by the p21 expression adenovirus, and 2) a cdk2 dominant-negative adenovirus also protected cells from cisplatin-induced apoptosis. Thus the data suggest that the mechanism of p21 protection is by direct inhibition of cdk2 activity and that cisplatin-induced apoptosis is caused by a cdk2-dependent pathway.

scholarly journals Pro-Inflammatory Cytokines Reduce the Proliferation of NG2 Cells and Increase Shedding of NG2 In Vivo and In Vitro

PLoS ONE ◽  
2014 ◽  
Vol 9 (10) ◽  
pp. e109387 ◽  
Author(s):  
Malin Wennström ◽  
Shorena Janelidze ◽  
Cecilie Bay-Richter ◽  
Lennart Minthon ◽  
Lena Brundin
Keyword(s):  
Inflammatory Cytokines ◽  
Ng2 Cells ◽  
Pro Inflammatory Cytokines

scholarly journals Inhibition of Vibrio anguillarum byPseudomonas fluorescens AH2, a Possible Probiotic Treatment of Fish

1999 ◽  
Vol 65 (3) ◽  
pp. 969-973 ◽  
Author(s):  
Lone Gram ◽  
Jette Melchiorsen ◽  
Bettina Spanggaard ◽  
Ingrid Huber ◽  
Torben F. Nielsen
Keyword(s):  
Iron Concentration ◽  
Vibrio Anguillarum ◽  
Fish Farming ◽  
Fish Pathogen ◽  
Probiotic Treatment ◽  
Treated Fish ◽  
Culture Supernatants ◽  
Probiotic Effect

ABSTRACT To study the possible use of probiotics in fish farming, we evaluated the in vitro and in vivo antagonism of antibacterial strainPseudomonas fluorescens strain AH2 against the fish-pathogenic bacterium Vibrio anguillarum. As iron is important in virulence and bacterial interactions, the effect ofP. fluorescens AH2 was studied under iron-rich and iron-limited conditions. Sterile-filtered culture supernatants from iron-limited P. fluorescens AH2 inhibited the growth ofV. anguillarum, whereas sterile-filtered supernatants from iron-replete cultures of P. fluorescens AH2 did not.P. fluorescens AH2 inhibited the growth of V. anguillarum during coculture, independently of the iron concentration, when the initial count of the antagonist was 100 to 1,000 times greater that of the fish pathogen. These in vitro results were successfully repeated in vivo. A probiotic effect in vivo was tested by exposing rainbow trout (Oncorynchus mykissWalbaum) to P. fluorescens AH2 at a density of 105 CFU/ml for 5 days before a challenge with V. anguillarum at 104 to 105 CFU/ml for 1 h. Some fish were also exposed to P. fluorescens AH2 at 107 CFU/ml during the 1-h infection. The combined probiotic treatment resulted in a 46% reduction of calculated accumulated mortality; accumulated mortality was 25% after 7 days at 12°C in the probiotic-treated fish, whereas mortality was 47% in fish not treated with the probiont.

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