1.Nucleocapsid protein from porcine epidemic diarrhea virus isolates can antagonize interferon-λ production by blocking the nuclear factor-κB nuclear translocation.
Ying SHAN ; Zi-Qi LIU ; Guo-Wei LI ; Cong CHEN ; Hao LUO ; Ya-Jie LIU ; Xun-Hui ZHUO ; Xing-Fen SHI ; Wei-Huan FANG ; Xiao-Liang LI
Journal of Zhejiang University. Science. B 2018;19(7):570-580
Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that can cause severe diseases in pigs and result in enormous economic losses in the worldwide swine industry. Previous studies revealed that PEDV exhibits an obvious capacity for modulating interferon (IFN) signaling or expression. The newly discovered type III IFN, which plays a crucial role in antiviral immunity, has strong antiviral activity against PEDV proliferation in IPEC-J2 cells. In this study, we aimed to investigate the effect of PEDV nucleocapsid (N) protein on type III IFN-λ. We found that the N proteins of ten PEDV strains isolated between 2013 and 2017 from different local farms shared high nucleotide identities, while the N protein of the CV777 vaccine strain formed a monophyletic branch in the phylogenetic tree. The N protein of the epidemic strain could antagonize type III IFN, but not type I or type II IFN expression induced by polyinosinic-polycytidylic acid (poly(I:C)) in IPEC-J2 cells. Subsequently, we demonstrated that the inhibition of poly(I:C)-induced IFN-λ3 production by PEDV N protein was dependent on the blocking of nuclear factor-κB (NF-κB) nuclear translocation. These findings might help increase understanding of the pathogenesis of PEDV and its mechanisms for evading the host immune response.
Active Transport, Cell Nucleus
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Animals
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Coronavirus Infections
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immunology
;
veterinary
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virology
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Genes, Viral
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Host-Pathogen Interactions
;
immunology
;
Interferons
;
antagonists & inhibitors
;
biosynthesis
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genetics
;
Interleukins
;
antagonists & inhibitors
;
biosynthesis
;
genetics
;
NF-kappa B
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metabolism
;
Nucleocapsid Proteins
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genetics
;
immunology
;
physiology
;
Porcine epidemic diarrhea virus
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genetics
;
pathogenicity
;
physiology
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Promoter Regions, Genetic
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Swine
;
Swine Diseases
;
immunology
;
virology
2.Discovery of synergistic anti-inflammatory compound combination from herbal formula GuGe FengTong Tablet.
Le-Le LIU ; Qun LIU ; Ping LI ; E-Hu LIU
Chinese Journal of Natural Medicines (English Ed.) 2018;16(9):683-692
Multi-components in herbal formulae exert holistic effects in synergistic or additive manners. However, appropriate strategies and supportive evidences are still lacking to uncover the synergistic or additive combinations. The present investigation aimed at seeking a screening strategy to identify the targeted combinations in GuGe FengTong Tablet (GGFTT), an herbal formula. Two compounds, belonging to different chemical classes, were combined with different concentration ratios and their anti-inflammation effects were investigated. The most significant anti-inflammatory combinations were evaluated by combination index (CI) method (additive effect, CI = 1; synergism, CI < 1; antagonism, CI > 1). The modulating effects of candidate combinations on pro-inflammatory cytokines and MAPKs signaling pathway were also detected. Two combinations, "biochanin A + 6-gingerol" (Bio-6G) and "genistein + 6-gingerol" (Gen-6G), showed synergistic effects (CI < 1), and Bio-6G was selected for further study. Compared with single compound, Bio-6G could synergistically inhibit the production of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) and the activation of MAPKs signaling pathway in LPS-stimulated RAW264.7 cells. The combined results showed that Bio-6G was a synergistic anti-inflammatory combination in GGFTT. Our results could provide a useful strategy to screen the synergistic combinations in herbal formulae.
Animals
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Anti-Inflammatory Agents
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chemistry
;
pharmacology
;
Drug Compounding
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Drug Synergism
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Drugs, Chinese Herbal
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chemistry
;
pharmacology
;
Interleukin-1beta
;
immunology
;
Macrophages
;
drug effects
;
immunology
;
Mice
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NF-kappa B
;
immunology
;
RAW 264.7 Cells
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Tablets
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chemistry
;
pharmacology
;
Tumor Necrosis Factor-alpha
;
immunology
3.Norisoboldine, a natural aryl hydrocarbon receptor agonist, alleviates TNBS-induced colitis in mice, by inhibiting the activation of NLRP3 inflammasome.
Qi LV ; Kai WANG ; Si-Miao QIAO ; Yue DAI ; Zhi-Feng WEI
Chinese Journal of Natural Medicines (English Ed.) 2018;16(3):161-174
Although the etiology of inflammatory bowel disease is still uncertain, increasing evidence indicates that the excessive activation of NLRP3 inflammasome plays a major role. Norisoboldine (NOR), an alkaloid isolated from Radix Linderae, has previously been demonstrated to inhibit inflammation and IL-1β production. The present study was to examine the effect of NOR on colitis and the underlying mechanism related to NLRP3 inflammasome activation. Our results showed that NOR alleviated colitis symptom in mice induced by 2, 4, 6-trinitrobenzene sulfonic acid (TNBS). Moreover, it significantly reduced expressions of cleaved IL-1β, NLRP3 and cleaved Caspase-1 but not ASC in colons of mice. In THP-1 cells, NOR suppressed the expressions of NLRP3, cleaved Caspase-1 and cleaved IL-1β but not ASC induced by lipopolysaccharide (LPS) and adenosine triphosphate (ATP). Furthermore, NOR could activate aryl hydrocarbon receptor (AhR) in THP-1 cells, inducing CYP1A1 mRNA expression, and promoting dissociation of AhR/HSP90 complexes, association of AhR and ARNT, AhR nuclear translocation, XRE reporter activity and binding activity of AhR/ARNT/XRE. Both siAhR and α-naphthoflavone (α-NF) markedly diminished the inhibition of NOR on NLRP3 inflammasome activation. In addition, NOR elevated Nrf2 level and reduced ROS level in LPS- and ATP-stimulated THP-1 cells, which was reversed by either siAhR or α-NF treatment. Finally, correlations between activation of AhR and attenuation of colitis, inhibition of NLRP3 inflammasome activation and up-regulation of Nrf2 level in colons were validated in mice with TNBS-induced colitis. Taken together, NOR ameliorated TNBS-induced colitis in mice through inhibiting NLRP3 inflammasome activation via regulating AhR/Nrf2/ROS signaling pathway.
Alkaloids
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administration & dosage
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Animals
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Colitis
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chemically induced
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drug therapy
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genetics
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immunology
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Drugs, Chinese Herbal
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administration & dosage
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Humans
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Inflammasomes
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drug effects
;
immunology
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Interleukin-1beta
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genetics
;
immunology
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Lindera
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chemistry
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Male
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Mice
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Mice, Inbred BALB C
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NF-kappa B
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genetics
;
immunology
;
Receptors, Aryl Hydrocarbon
;
agonists
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genetics
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metabolism
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Trinitrobenzenesulfonic Acid
;
adverse effects
4.Noni (Morinda citrifolia L.) fruit juice delays immunosenescence in the lymphocytes in lymph nodes of old F344 rats.
Uday P PRATAP ; Hannah P PRIYANKA ; Karthik R RAMANATHAN ; Vishak RAMAN ; Lalgi HIMA ; Srinivasan THYAGARAJAN
Journal of Integrative Medicine 2018;16(3):199-207
<b>OBJECTIVEb>Aging is associated with the development of diseases because of immunosuppression and altered functioning of the neuroendocrine system. The medicinal properties of Morinda citrifolia L. have been widely exploited for the treatment of age-associated diseases. This study aims to investigate the in vitro and in vivo effects of noni (M. citrifolia) fruit juice (NFJ) on neuro-immunomodulation in the lymph node lymphocytes of F344 rats.
<b>METHODSb>Lymphocytes isolated from axillary and inguinal lymph nodes of young (3-4 months) and old (18-21 months) rats were treated in vitro with different concentrations (0.0001%, 0.01%, and 1%) of NFJ for a period of 24 h. In the in vivo study, old (16-17 months) male F344 rats were treated with 5 mL/kg body weight of 5%, 10% and 20% of NFJ, twice a day, by oral gavage, and lymph node lymphocytes were isolated after 60 d. Concanavalin A (Con A)-induced lymphocyte proliferation, interleukin-2 (IL-2) and interferon-γ (IFN-γ) production and expression of intracellular markers, such as phospho-extracellular signal-regulated kinase (p-ERK1/2), phospho-cAMP response element-binding protein, phospho-protein kinase B (p-Akt), phospho-tyrosine hydroxylase (p-TH), phospho-nuclear factor of κ light polypeptide gene enhancer in B-cells inhibitor-α (p-IκB-α) and phospho-nuclear factor-κB (p-NF-κB p65 and p50) were examined in the lymphocytes of lymph nodes.
<b>RESULTSb>NFJ increased Con A-induced lymphocyte proliferation, IL-2 and IFN-γ production, and p-ERK1/2 expression both in vitro and in vivo. In in vivo NFJ-treated old rats, lymph node lymphocytes showed increased expression of p-TH and Akt, nitric oxide production and decreased expression of p-NF-κB p65 and p50.
<b>CONCLUSIONb>These results suggest that the immunostimulatory properties of NFJ are facilitated through intracellular signaling pathways involving ERK1/2, Akt and NF-κB.
Adjuvants, Immunologic ; metabolism ; Aging ; immunology ; metabolism ; Animals ; Cell Proliferation ; Fruit ; chemistry ; metabolism ; Fruit and Vegetable Juices ; analysis ; Humans ; Interleukin-2 ; immunology ; Lymph Nodes ; cytology ; immunology ; Lymphocytes ; cytology ; immunology ; Male ; Morinda ; chemistry ; metabolism ; NF-kappa B ; immunology ; Plant Preparations ; metabolism ; Rats ; Rats, Inbred F344 ; Transcription Factor RelA ; immunology
5.Sub-anesthesia Dose of Isoflurane in 60% Oxygen Reduces Inflammatory Responses in Experimental Sepsis Models.
Yi HUANG ; Xiao-Xia WANG ; Dong-Dong SUN ; Ze-Xin ZHANG ; Wan-Wan YANG ; Tian SHAO ; Han HAN ; Er-Fei ZHANG ; Zhong-Shu PU ; Zuo-Xu HOU ; Hai-Long DONG ; Li-Ze XIONG ; Li-Chao HOU
Chinese Medical Journal 2017;130(7):840-853
<b>BACKGROUNDb>Sepsis is a major cause of mortality in Intensive Care Units. Anesthetic dose isoflurane and 100% oxygen were proved to be beneficial in sepsis; however, their application in septic patients is limited because long-term hyperoxia may induce oxygen toxicity and anesthetic dose isoflurane has potential adverse consequences. This study was scheduled to find the optimal combination of isoflurane and oxygen in protecting experimental sepsis and its mechanisms.
<b>METHODSb>The effects of combined therapy with isoflurane and oxygen on lung injury and sepsis were determined in animal models of sepsis induced by cecal ligation and puncture (CLP) or intraperitoneal injection of lipopolysaccharide (LPS) or zymosan. Mouse RAW264.7 cells or human peripheral blood mononuclear cells (PBMCs) were treated by LPS to probe mechanisms. The nuclear factor kappa B (NF-κB) signaling molecules were examined by Western blot and cellular immunohistochemistry.
<b>RESULTSb>The 0.5 minimum alveolar concentration (MAC) isoflurane in 60% oxygen was the best combination of oxygen and isoflurane for reducing mortality in experimental sepsis induced by CLP, intraperitoneal injection of LPS, or zymosan. The 0.5 MAC isoflurane in 60% oxygen inhibited proinflammatory cytokines in peritoneal lavage fluids (tumor necrosis factor-alpha [TNF-β]: 149.3 vs. 229.7 pg/ml, interleukin [IL]-1β: 12.5 vs. 20.6 pg/ml, IL-6: 86.1 vs. 116.1 pg/ml, and high-mobility group protein 1 [HMGB1]: 323.7 vs. 449.3 ng/ml; all P< 0.05) and serum (TNF-β: 302.7 vs. 450.7 pg/ml, IL-1β: 51.7 vs. 96.7 pg/ml, IL-6: 390.4 vs. 722.5 pg/ml, and HMGB1: 592.2 vs. 985.4 ng/ml; all P< 0.05) in septic animals. In vitro experiments showed that the 0.5 MAC isoflurane in 60% oxygen reduced inflammatory responses in mouse RAW264.7 cells, after LPS stimulation (all P< 0.05). Suppressed activation of NF-κB pathway was also observed in mouse RAW264.7 macrophages and human PBMCs after LPS stimulation or plasma from septic patients. The 0.5 MAC isoflurane in 60% oxygen also prevented the increases of phospho-IKKβ/β, phospho-IκBβ, and phospho-p65 expressions in RAW264.7 macrophages after LPS stimulation (all P< 0.05).
<b>CONCLUSIONb>Combined administration of a sedative dose of isoflurane with 60% oxygen improves survival of septic animals through reducing inflammatory responses.
Adult ; Anesthesia ; methods ; Animals ; Blotting, Western ; Bronchoalveolar Lavage Fluid ; Disease Models, Animal ; Female ; Humans ; Inflammation ; drug therapy ; Isoflurane ; therapeutic use ; Leukocytes, Mononuclear ; metabolism ; Lipopolysaccharide Receptors ; metabolism ; Lipopolysaccharides ; pharmacology ; Lung Injury ; drug therapy ; immunology ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; NF-kappa B ; metabolism ; Oxygen ; therapeutic use ; Peroxidase ; metabolism ; RAW 264.7 Cells ; Rats, Sprague-Dawley ; Sepsis ; drug therapy ; immunology ; Tumor Necrosis Factor-alpha ; metabolism
6.Mangiferin ameliorates insulin resistance by inhibiting inflammation and regulatiing adipokine expression in adipocytes under hypoxic condition.
Chao-Qiang YANG ; Jing-Hua XU ; Dan-Dan YAN ; Bao-Lin LIU ; Kang LIU ; Fang HUANG
Chinese Journal of Natural Medicines (English Ed.) 2017;15(9):664-673
Adipose tissue hypoxia has been recognized as the initiation of insulin resistance syndromes. The aim of the present study was to investigate the effects of mangiferin on the insulin signaling pathway and explore whether mangiferin could ameliorate insulin resistance caused by hypoxia in adipose tissue. Differentiated 3T3-L1 adipocytes were incubated under normal and hypoxic conditions, respectively. Protein expressions were analyzed by Western blotting. Inflammatory cytokines and HIF-1-dependent genes were tested by ELISA and q-PCR, respectively. The glucose uptake was detected by fluorescence microscopy. HIF-1α was abundantly expressed during 8 h of hypoxic incubation. Inflammatory reaction was activated by up-regulated NF-κB phosphorylation and released cytokines like IL-6 and TNF-α. Glucose uptake was inhibited and insulin signaling pathway was damaged as well. Mangiferin substantially inhibited the expression of HIF-1α. Lactate acid and lipolysis, products released by glycometabolism and lipolysis, were also inhibited. The expression of inflammatory cytokines was significantly reduced and the damaged insulin signaling pathway was restored to proper functional level. The glucose uptake of hypoxic adipocytes was promoted and the dysfunction of adipocytes was relieved. These results showed that mangiferin could not only improve the damaged insulin signaling pathway in hypoxic adipocytes, but also ameliorate inflammatory reaction and insulin resistance caused by hypoxia.
3T3-L1 Cells
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Adipocytes
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drug effects
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immunology
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Adipokines
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genetics
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immunology
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Animals
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Cell Hypoxia
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drug effects
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Glucose
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metabolism
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Humans
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Hypoxia-Inducible Factor 1, alpha Subunit
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genetics
;
immunology
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Insulin
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metabolism
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Insulin Resistance
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Mice
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NF-kappa B
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genetics
;
immunology
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Oxygen
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metabolism
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Tumor Necrosis Factor-alpha
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genetics
;
immunology
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Xanthones
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pharmacology
7.Anti-inflammatory effects of traditional mixed extract of medicinal herbs (MEMH) on monosodium urate crystal-induced gouty arthritis.
Ju-Suk NAM ; Supriya JAGGA ; Ashish Ranjan SHARMA ; Joon-Hee LEE ; Jong Bong PARK ; Jun-Sub JUNG ; Sang-Soo LEE
Chinese Journal of Natural Medicines (English Ed.) 2017;15(8):561-575
Korean oriental medicine prescription is widely used for the treatment of gouty diseases. In the present study, we investigated anti-inflammatory effects of modified Korean herbal formulation, mixed extract of medicinal herbs (MEMH), and its modulatory effects on inflammatory mediators associated with gouty arthritis. Both in vitro and in vivo studies were carried out to assess the anti-inflammatory efficacy of MEMH on monosodium urate (MSU) crystals-induced gouty inflammation. MSU crystals stimulated human chondrosarcoma cell line, SW1353, and human primary chondrocytes were treated with MEMH in vitro. The expression levels of pro-inflammatory mediators and metalloproteases were analyzed. The effect of MEMH on NFκB signaling pathway in SW1353 cells was examined. Effect of MEMH on the mRNA expression level of pro-inflammatory mediators and chemotactic factor from human monocytic cell line, THP-1, was also analyzed. The probable role of MEMH in the differentiation process of osteoblast like cells, SaOS-2, after MSU treatment was also observed. To investigate the effects of MEMH in vivo, MSU crystals-induced ankle arthritic model was established. Histopathological changes in affected joints and plasma levels of pro-inflammatory mediators (IL-1β and TNFα) were recorded. MEMH inhibited NFκB signaling pathway and COX-2 protein expression in chondrocytes. MSU-induced mRNA expressions of pro-inflammatory mediators and chemotactic cytokines were suppressed by MEMH. In MSU crystals-induced ankle arthritic mouse model, administration of MEMH relieved inflammatory symptoms and decreased the plasma levels of IL-1β and TNFα. The results indicated that MEMH can effectively inhibit the expression of inflammatory mediators in gouty arthritis, demonstrating its potential for treating gouty arthritis.
Anti-Inflammatory Agents
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administration & dosage
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Arthritis, Gouty
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chemically induced
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drug therapy
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genetics
;
immunology
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Cell Line
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Chondrocytes
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drug effects
;
immunology
;
Drugs, Chinese Herbal
;
administration & dosage
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Humans
;
Interleukin-1beta
;
genetics
;
immunology
;
NF-kappa B
;
genetics
;
immunology
;
Plants, Medicinal
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chemistry
;
Tumor Necrosis Factor-alpha
;
genetics
;
immunology
;
Uric Acid
;
adverse effects
8.Differences in anti-inflammatory effects between two specifications of Scutellariae Radix in LPS-induced macrophages in vitro.
Qian-Yu CHEN ; Chao-Qun WANG ; Zhi-Wei YANG ; Qi TANG ; Huan-Ran TAN ; Xuan WANG ; Shao-Qing CAI
Chinese Journal of Natural Medicines (English Ed.) 2017;15(7):515-524
Scutellariae Radix (SR), the root of Scutellaria baicalensis Georgi, is used as an antipyretic drug and has been demonstrated to have anti-inflammatory activity. SR is divided into two specifications, "Ku Qin" (KQ) and "Zi Qin" (ZQ), for use against different symptoms (upper energizer heat or lower portion of the triple energizer), according to the theory of traditional Chinese medicine (TCM). However, differences in the efficacies of these two specifications have not been determined. In the present study, we aimed to characterize the differences in the anti-inflammatory activities between KQ and ZQ and to explore how their differences are manifested in lipopolysaccharide (LPS)-induced macrophages. Our results showed that, in RAW264.7 cells (a mouse macrophage cell line derived from ascites), KQ and ZQ displayed anti-inflammatory effects by inhibiting the release of nitric oxide (NO), inducible NOS (iNOS), and nuclear factor-κB (NF-κB) in a dose-dependent manner without distinction. In NR8383 cells (a rat alveolar macrophage cell line), KQ and ZQ displayed similar effects on NO, iNOS, and NF-κB as seen in RAW264.7 cells, but KQ showed a higher inhibition rate for NO and iNOS than that shown by ZQ at the same concentration. These results indicated that there were differences in efficacy between KQ and ZQ in treating lung inflammation. Our findings provided an experimental evidence supporting the different uses of KQ and ZQ in clinic, as noted in ancient herbal records.
Animals
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Anti-Inflammatory Agents
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pharmacology
;
Cell Line
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Lipopolysaccharides
;
pharmacology
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Macrophages
;
drug effects
;
immunology
;
Mice
;
NF-kappa B
;
genetics
;
immunology
;
Nitric Oxide Synthase Type II
;
genetics
;
immunology
;
RAW 264.7 Cells
;
Rats
;
Scutellaria baicalensis
;
chemistry
9.Effect of inhibiting TIM-4 function in Kupffer cells on liver graft rejection in mice.
Xue-Qiang LI ; Xu-Hong LI ; Shi-Gang DUAN ; Xue-Song XU ; Yi-Ming LIU ; Jin-Zheng LI ; Jian-Ping GONG ; Hao WU
Journal of Southern Medical University 2016;37(4):451-459
<b>OBJECTIVEb>To investigate the effects of inhibiting TIM-4 function in Kupffer cells (KCs) on liver graft rejection in mice and explore the underlying mechanism.
<b>METHODSb>Mouse models of orthotopic liver transplantation were treated with a control mAb group and TIM-4 mAb. The activated KCs were assayed with immunohistochemistry after operation. The expression of TIM-4 in KCs were assayed with Western blotting and RT-PCR and the levels of AST, ALT, TBIL, TNF-α, IFN-γ and CCL2 were assayed detected. The expression of TIM-4 in KCs was observed with laser confocal microscopy. HE staining was used to observe the microstructure of the liver tissues, and the number of CD25Foxp3T cells was determined using with flow cytometry; the proteins levels of p-P65and p-P38 were assayed with Western blotting. The donor mice were treated with clodronate liposomes to destroy the KCs in the liver before transplantation, and the liver grafts were examined for graft rejection.
<b>RESULTSb>The number of activated KCs in the liver graft increased progressively over time. Compared with the sham-operated group, the liver graft showed significantly increased TIM-4 protein and mRNA levels at 1, 3, and 7 days after transplantation (P<0.05) and increased levels of AST, ALT, TBIL, TNF-α, IFN-γ and CCL2 at 7 days (P<0.05). The graft in TIM-4 mAb group showed mild pathological changes with a mean RAI score of 2.67∓0.75, which was significantly lower than that in control mAb group (P<0.05). The mean survival time of the recipient mice was 53.8∓6.4 days in TIM-4 mAb group, significantly longer than that in the control mAB group (14.5∓2.9 days, P<0.05). Donor treatment with clodronate liposomes resulted in comparable RAI scores in TIM-4 mAb and control mAb groups (8.01∓0.64 vs 7.93∓0.56, P>0.05). The protein levels of p-P65 and p-P38 in TIM-4 mAb group were significantly lower than those in control mAb group (P<0.05), and CD25Foxp3T cells in the liver graft increased significantly in TIM-4 mAb group.
<b>CONCLUSIONb>Inhibition of TIM-4 function in KCs reduces the production of inflammatory factors after liver transplantation possibly by inhibiting the NF-κB and MAPK signaling pathways and promoting the proliferation of Foxp3Treg cells to induce allograft tolerance.
Animals ; Antibodies, Monoclonal ; pharmacology ; Graft Rejection ; Immunohistochemistry ; Kupffer Cells ; drug effects ; metabolism ; Liver ; surgery ; Liver Transplantation ; Male ; Membrane Proteins ; antagonists & inhibitors ; Mice ; NF-kappa B ; metabolism ; T-Lymphocytes, Regulatory ; immunology
10.alpha-Lipoic Acid Inhibits Expression of IL-8 by Suppressing Activation of MAPK, Jak/Stat, and NF-kappaB in H. pylori-Infected Gastric Epithelial AGS Cells.
Ji Hyun CHOI ; Soon Ok CHO ; Hyeyoung KIM
Yonsei Medical Journal 2016;57(1):260-264
The epithelial cytokine response, associated with reactive oxygen species (ROS), is important in Helicobacter pylori (H. pylori)-induced inflammation. H. pylori induces the production of ROS, which may be involved in the activation of mitogen-activated protein kinases (MAPK), janus kinase/signal transducers and activators of transcription (Jak/Stat), and oxidant-sensitive transcription factor, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB), and thus, expression of interleukin-8 (IL-8) in gastric epithelial cells. alpha-lipoic acid, a naturally occurring thiol compound, is a potential antioxidant. It shows beneficial effects in treatment of oxidant-associated diseases including diabetes. The present study is purposed to investigate whether alpha-lipoic acid inhibits expression of inflammatory cytokine IL-8 by suppressing activation of MAPK, Jak/Stat, and NF-kappaB in H. pylori-infected gastric epithelial cells. Gastric epithelial AGS cells were pretreated with or without alpha-lipoic acid for 2 h and infected with H. pylori in a Korean isolate (HP99) at a ratio of 300:1. IL-8 mRNA expression was analyzed by RT-PCR analysis. IL-8 levels in the medium were determined by enzyme-linked immunosorbent assay. NF-kappaB-DNA binding activity was determined by electrophoretic mobility shift assay. Phospho-specific and total forms of MAPK and Jak/Stat were assessed by Western blot analysis. ROS levels were determined using dichlorofluorescein fluorescence. As a result, H. pylori induced increases in ROS levels, mRNA, and protein levels of IL-8, as well as the activation of MAPK [extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinase 1/2 (JNK1/2), p38], Jak/Stat (Jak1/2, Stat3), and NF-kappaB in AGS cells, which was inhibited by alpha-lipoic acid. In conclusion, alpha-lipoic acid may be beneficial for prevention and/or treatment of H. pylori infection-associated gastric inflammation.
Enzyme-Linked Immunosorbent Assay
;
Epithelial Cells/metabolism
;
Gastric Mucosa/*drug effects/metabolism/microbiology
;
Gene Expression Regulation, Bacterial
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Helicobacter Infections/immunology/*metabolism
;
Helicobacter pylori/drug effects/*pathogenicity
;
Humans
;
Interleukin-8/genetics/*metabolism
;
JNK Mitogen-Activated Protein Kinases
;
Janus Kinase 1
;
Mitogen-Activated Protein Kinases/*biosynthesis
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NF-kappa B/*metabolism
;
RNA, Messenger/isolation & purification/metabolism
;
Reactive Oxygen Species/metabolism
;
STAT3 Transcription Factor
;
Stomach/metabolism/*microbiology
;
Thioctic Acid/*pharmacology

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