OBJECTIVETo investigate the effects of prophylactic administration of all-trans retinoic acid (ATRA) in relieving inflammation in a rat model of collagen-induced arthritis (CIA).

METHODSFemale Wistar rats (6 to 8 weeks old) were randomly divided into normal control group, solvent control group, and prophylactic ATRA treatment (0.05, 0.5, and 5 mg/kg) groups. All the rats except for those in normal control group were subjected to subcutaneous injection of type II collagen and incomplete Freund adjuvant in the tails to induce CIA, followed by injection on the following day with saline, corn oil or different doses of ATRA 3 times a week. The arthritis index (AI) scores, histological scores, serum levels of TNF-α, IL-17A, and IL-10, and expressions of proteases related with cartilage damage were evaluated.

RESULTSOn the 15th day after the primary immunization, the AI scores increased significantly in all but the normal control groups; the scores increased progressively in all the 3 ATRA groups but remained lower than that in the solvent control group, which was stable over time. The rats in the 3 ATRA groups showed obvious pathologies in the knee and ankle joints, but the semi-quantitative scores of pathology damage showed no significance among them. Compared with those in solvent control group, the serum IL-17A and TNF-α levels decreased, serum IL-10 level increased, and the expressions of ADAMT-4 and MMP-3 proteins decreased significantly in the knees in the 3 ATRA groups.

CONCLUSIONATRA can reduce the production of TNF-α and IL-17A and increase the production of IL-10 to alleviate the inflammation in rats with CIA. ATRA may delay the progression of RA by correcting the imbalance of Th1/Th2 and Th17/Treg.

ADAMTS4 Protein ; metabolism ; Animals ; Arthritis, Experimental ; chemically induced ; drug therapy ; Collagen Type II ; Female ; Freund's Adjuvant ; Inflammation ; drug therapy ; Interleukin-10 ; blood ; Interleukin-17 ; blood ; Lipids ; Matrix Metalloproteinase 3 ; metabolism ; Rats ; Rats, Wistar ; T-Lymphocytes, Regulatory ; immunology ; Th17 Cells ; immunology ; Tretinoin ; pharmacology ; Tumor Necrosis Factor-alpha ; blood

Eupatilin is the main active component of DA-9601, an extract from Artemisia. Recently, eupatilin was reported to have anti-inflammatory properties. We investigated the anti-arthritic effect of eupatilin in a murine arthritis model and human rheumatoid synoviocytes. DA-9601 was injected into collagen-induced arthritis (CIA) mice. Arthritis score was regularly evaluated. Mouse monocytes were differentiated into osteoclasts when eupatilin was added simultaneously. Osteoclasts were stained with tartrate-resistant acid phosphatase and then manually counted. Rheumatoid synoviocytes were stimulated with TNF-alpha and then treated with eupatilin, and the levels of IL-6 and IL-1beta mRNA expression in synoviocytes were measured by RT-PCR. Intraperitoneal injection of DA-9601 reduced arthritis scores in CIA mice. TNF-alpha treatment of synoviocytes increased the expression of IL-6 and IL-1beta mRNAs, which was inhibited by eupatilin. Eupatilin decreased the number of osteoclasts in a concentration dependent manner. These findings, showing that eupatilin and DA-9601 inhibited the expression of inflammatory cytokines and the differentiation of osteoclasts, suggest that eupatilin and DA-9601 is a candidate anti-inflammatory agent.
Animals ; Anti-Inflammatory Agents/pharmacology/*therapeutic use ; Arthritis, Experimental/chemically induced/*drug therapy ; Arthritis, Rheumatoid/drug therapy/pathology ; Cell Differentiation/*drug effects ; Cells, Cultured ; Collagen Type II ; Cytokines/biosynthesis ; Disease Models, Animal ; Drugs, Chinese Herbal/therapeutic use ; Female ; Flavonoids/pharmacology/*therapeutic use ; Humans ; Inflammation/drug therapy/immunology ; Interleukin-1beta/genetics/metabolism ; Interleukin-6/genetics/metabolism ; Lymph Nodes/cytology ; Mice ; Mice, Inbred DBA ; Monocytes/cytology ; Osteoclasts/*cytology ; Plant Extracts/pharmacology ; RNA, Messenger/biosynthesis ; Synovial Membrane/cytology ; T-Lymphocytes, Regulatory/cytology/immunology ; Tumor Necrosis Factor-alpha/pharmacology

BACKGROUNDProtectin D1 (PD1), derived from docosahexaenoic acid, has been shown to control and resolve inflammation in some experimental models of inflammatory disorders. We investigated the protective roles of protectin D1 in pulmonary inflammation and lung injury induced by lipopolysaccharide (LPS).

METHODSMice were randomly assigned to six groups (n = 6 per group): sham-vehicle group, sham-PD1 group, sham-zVAD-fmk group, LPS-vehicle group, LPS-PD1 group, and LPS-PD1-zVAD-fmk group. Mice were injected intratracheally with 3 mg/kg LPS or saline, followed 24 hours later by intravenous injection of 200 µg/mouse PD1 or vehicle. At the same time, some mice were also injected intraperitoneally with the pan-caspase inhibitor zVAD-fmk. Seventy-two hours after LPS challenge, samples of pulmonary tissue and bronchoalveolar lavage fluid were collected. Optical microscopy was used to examine pathological changes in lungs. Cellularity and protein concentration in bronchoalveolar lavage fluid were analyzed. Lung wet/dry ratios and myeloperoxidase activity were measured. Apoptosis of neutrophils in bronchoalveolar lavage fluid (BALF) was also evaluated by flow cytometry.

RESULTSIntratracheal instillation of LPS increased neutrophil counts, protein concentration in bronchoalveolar lavage fluid and myeloperoxidase activity, it induced lung histological injury and edema, and also suppressed apoptosis of neutrophils in BALF. Posttreatment with PD1 inhibited LPS-evoked changes in BALF neutrophil counts and protein concentration and lung myeloperoxidase activity, with the outcome of decreased pulmonary edema and histological injury. In addition, PD1 promoted apoptosis of neutrophils in BALF. The beneficial effects of PD1 were blocked by zVAD-fmk.

CONCLUSIONPosttreatment with PD1 enhances resolution of lung inflammation during LPS-induced acute lung injury by enhancing apoptosis in emigrated neutrophils, which is, at least in part, caspase-dependent.

Acute Lung Injury ; chemically induced ; drug therapy ; immunology ; Animals ; Apoptosis ; drug effects ; Docosahexaenoic Acids ; therapeutic use ; Inflammation ; drug therapy ; Lipopolysaccharides ; toxicity ; Male ; Mice ; Mice, Inbred BALB C ; Neutrophils ; cytology ; drug effects ; Peroxidase ; metabolism

BACKGROUNDExcessive iodine intake and viral infection are recognized as both critical factors associated with autoimmune thyroid diseases. Toll-like receptors (TLRs) have been reported to play an important role in autoimmune and inflammatory disorders. In this study, we aimed to clarify the possible mechanism of TLR3 involved in polyinosine-polycytidylic acid (poly(I:C)) promoting excessive iodine intake induced thyroiditis in non-obese diabetic (NOD) mice.

METHODSBoth NOD and BALB/c mice were randomly assigned to four groups: control group (n = 5), high iodine intake (HI) group (n = 7), poly(I:C) group (n = 7) and combination of excessive iodine and poly(I:C) injection (HIP) group (n = 7). After 8 weeks, mice were weighed and blood samples were collected. All the mice were sacrificed before dissection of spleen and thyroid gland. Then, thyroid histology, thyroid secreted hormone, expression of CD3(+) cells and TLR3 as well as inflammatory mRNA level were evaluated.

RESULTSBoth NOD and BALB/c mice from HI and HIP group represented goiter and increasing thyroid relative weight. Thyroid histology evidence indicated that only HIP group of NOD mice showed severe thyroiditis with lymphocytes infiltration in majority of thyroid tissue, severe damage of follicles and general fibrosis. Immunofluorescence staining results displayed a large number of CD3(+) cells in HIP NOD mice. Real-time polymerase chain reaction (PCR) results suggested interferon (IFN)-α increased over 30 folds and IFN-γ expression was doubled compared with control group, but interleukin (IL)-4 remained unchanged in HIP group of NOD mice thyroid. Meanwhile, over one third decrease of blood total thyroxine (TT4) and increased thyroid-stimulating hormone (TSH) was observed in HIP group of NOD mice. Only HIP group of NOD mice represented significantly elevation of TLR3 expression.

CONCLUSIONPoly(I:C) enhanced excessive dietary iodine induced thyroiditis in NOD mice through increasing TLR3 mediated inflammation.

Animals ; Female ; Inflammation ; chemically induced ; metabolism ; Iodine ; toxicity ; Mice ; Mice, Inbred NOD ; Poly I-C ; pharmacology ; Thyroiditis ; chemically induced ; immunology ; metabolism ; Toll-Like Receptor 3 ; metabolism

OBJECTIVE: In this study, we investigated the anti-inflammation effects of Xuebijing in OVA-induced murine allergic rhinitis model. Furthermore, we determined whether heme oxygenase (HO)-1 is required for the protective activity of Xuebijing. METHOD: Airways of OVA-sensitized mice exposed to OVA challenge developed eosinophilia, mucus hypersecretion and increased cytokine levels. Levels of interleukin IL-4, IL-5, IL-13, and tumor necrosis factor (TNF)-alpha in nasal lavage fluid were measured using enzyme-linked immunosorbent assays (ELISAs). Lung tissue and nasal mucosa sections were stained with Mayer's hematoxylin and eosin for assessment of cell infiltration and mucus production, Immunohistochemistry, Real-time PCR and Western Blot analyses for HO-1 protein expression. RESULT: Orally administered Xuebijing significantly inhibited the number of OVA-induced inflammatory cells and IgE production, along with reduced T-helper (Th) 2 cytokine levels, such as IL-4, IL-5 and IL-13, improved the level of IFN-gamma, in nasal lavage fluid. In addition, Xuebijing induced a marked decrease in OVA-induced inflammatory cell infiltration and mucus production in nasal and lung tissues. These effects were correlated with HO-1 mRNA and protein induction. CONCLUSION Our results indicate that Xuebijing protects against OVA-induced airway inflammation, at least in part, via HO-1 upregulation.
Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Eosinophilia ; metabolism ; Heme Oxygenase-1 ; metabolism ; Immunoglobulin E ; immunology ; Inflammation ; drug therapy ; metabolism ; Interleukin-13 ; metabolism ; Interleukin-4 ; metabolism ; Interleukin-5 ; metabolism ; Membrane Proteins ; metabolism ; Mice ; Nasal Mucosa ; metabolism ; Rhinitis, Allergic ; Rhinitis, Allergic, Perennial ; chemically induced ; drug therapy ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo evaluate the efficacy of boswellic acid against monosodium urate crystal-induced inflammation in mice.

METHODSThe mice were divided into four experimental groups. Group I served as control; mice in group II were injected with monosodium urate crystal; group III consisted of monosodium urate crystal-induced mice who were treated with boswellic acid (30 mg/kg/b.w.); group IV comprised monosodium urate crystal-induced mice who were treated with indomethacin (3 mg/kg/b.w.). Paw volume and levels/activities of lysosomal enzymes, lipid peroxidation, anti-oxidant status and inflammatory mediator TNF-α were determined in control and monosodium urate crystal-induced mice. In addition, the levels of β-glucuronidase and lactate dehydrogenase were also measured in monosodium urate crystal-incubated polymorphonuclear leucocytes (PMNL) in vitro.

RESULTSThe activities of lysosomal enzymes, lipid peroxidation, and tumour necrosis factor-α levels and paw volume were increased significantly in monosodium urate crystal-induced mice, whereas the activities of antioxidant status were in turn decreased. However, these changes were modulated to near normal levels upon boswellic acid administration. In vitro, boswellic acid reduced the level of β-glucuronidase and lactate dehydrogenase in monosodium urate crystal-incubated PMNL in concentration dependent manner when compared with control cells.

CONCLUSIONSThe results obtained in this study further strengthen the anti-inflammatory/antiarthritic effect of boswellic acid, which was already well established by several investigators.

Animals ; Anti-Inflammatory Agents ; therapeutic use ; Antioxidants ; therapeutic use ; Arthritis, Gouty ; chemically induced ; drug therapy ; Female ; Glucuronidase ; metabolism ; Hydrolases ; metabolism ; Indomethacin ; therapeutic use ; Inflammation ; chemically induced ; drug therapy ; L-Lactate Dehydrogenase ; metabolism ; Lipid Peroxidation ; drug effects ; Male ; Mice ; Neutrophils ; enzymology ; immunology ; Triterpenes ; therapeutic use ; Tumor Necrosis Factor-alpha ; blood ; Uric Acid

PURPOSE: Cockroach (CR) is an important inhalant allergen and can induce allergic asthma. However, the mechanism by which CR induces airway allergic inflammation and the role of endotoxin in CR extract are not clearly understood in regards to the development of airway inflammation. In this study, we evaluated whether endotoxin is essential to the development of CR induced airway allergic inflammation in mice. MATERIALS AND METHODS: Airway allergic inflammation was induced by intranasal administration of either CR extract, CR with additional endotoxin, or endotoxin depleted CR extract, respectively, in BALB/c wild type mice. CR induced inflammation was also evaluated with toll like receptor-4 (TLR-4) mutant (C3H/HeJ) and wild type (C3H/HeN) mice. RESULTS: Intranasal administration of CR extracts significantly induced airway hyperresponsiveness (AHR), eosinophilic and neutrophilic airway inflammation, as well as goblet cell hyperplasia in a dose-dependent manner. The addition of endotoxin along with CR allergen attenuated eosinophilic inflammation, interleukin (IL)-13 level, and goblet cell hyperplasia of respiratory epithelium; however, it did not affect the development of AHR. Endotoxin depletion in CR extract did not attenuate eosinophilic inflammation and lymphocytosis in BAL fluid, AHR and IL-13 expression in the lungs compared to CR alone. The attenuation of AHR, eosinophilic inflammation, and goblet cell hyperplasia induced by CR extract alone was not different between TLR-4 mutant and the wild type mice. In addition, heat inactivated CR extract administration induced attenuated AHR and eosinophilic inflammation. CONCLUSION: Endotoxin in CR extracts may not be essential to the development of airway inflammation.
Allergens/*immunology ; Animals ; Asthma/*chemically induced/*immunology/metabolism ; Cockroaches/*immunology ; Endotoxins/*immunology ; Enzyme-Linked Immunosorbent Assay ; Female ; Inflammation/*chemically induced/*immunology/metabolism ; Interferon-gamma/metabolism ; Interleukin-13/metabolism ; Interleukin-5/metabolism ; Mice ; Mice, Inbred BALB C ; Respiratory Hypersensitivity/chemically induced/*immunology

White fat cells secrete adipokines that induce inflammation and obesity has been reported to be characterized by high serum levels of inflammatory cytokines such as IL-6 and TNF-alpha. Rheumatoid arthritis (RA) is a prototype of inflammatory arthritis, but the relationship between RA and obesity is controversial. We made an obese inflammatory arthritis model: obese collagen-induced arthritis (CIA). C57BL/6 mice were fed a 60-kcal high fat diet (HFD) from the age of 4 weeks and they were immunized twice with type II collagen (CII). After immunization, the obese CIA mice showed higher arthritis index scores and histology scores and a more increased incidence of developing arthritis than did the lean CIA mice. After treatment with CII, mixed lymphocyte reaction also showed CII-specific response more intensely in the obese CIA mice than lean CIA. The anti-CII IgG and anti-CII IgG2a levels in the sera of the obese CIA mice were higher than those of the lean CIA mice. The number of Th17 cells was higher and the IL-17 mRNA expression of the splenocytes in the obese CIA mice was higher than that of the lean CIA mice. Obese CIA mice also showed high IL-17 expression on synovium in immunohistochemistry. Although obesity may not play a pathogenic role in initiating arthritis, it could play an important role in amplifying the inflammation of arthritis through the Th1/Th17 response. The obese CIA murine model will be an important tool when we investigate the effect of several therapeutic target molecules to treat RA.
Adipokines/immunology/metabolism ; Animals ; *Arthritis, Experimental/genetics/immunology/pathology ; Cell Differentiation/genetics/immunology ; *Collagen Type II/administration & dosage/immunology ; Disease Models, Animal ; Gene Expression ; Humans ; Inflammation/chemically induced/*immunology ; Interleukin-17/metabolism ; Interleukin-6/blood ; Joints/immunology/pathology ; Mice ; Mice, Inbred C57BL ; *Obesity/genetics/immunology/pathology ; *Th17 Cells/immunology/metabolism ; Tumor Necrosis Factor-alpha/blood

Many immune down-regulatory molecules have been isolated from parasites, including cystatin (cystain protease inhibitor). In a previous study, we isolated and characterized Type I cystatin (CsStefin-1) of the liver fluke, Clonorchis sinensis. To investigate whether the CsStefin-1 might be a new host immune modulator, we induced intestinal inflammation in mice by dextran sodium sulfate (DSS) and treated them with recombinant CsStefin-1 (rCsStefin-1). The disease activity index (DAI) increased in DSS only-treated mice. In contrast, the DAI value was significantly reduced in rCsStefin-1-treated mice than DSS only-treated mice. In addition, the colon length of DSS only-treated mice was shorter than that of rCsStefin-1 treated mice. The secretion levels of IFN-gamma and TNF-alpha in the spleen and mesenteric lymph nodes (MLNs) were significantly increased by DSS treatment, but the level of TNF-alpha in MLNs was significantly decreased by rCsStefin-1 treatment. IL-10 production in both spleen and MLNs was significantly increased, and IL-10+F4/80+ macrophage cells were significantly increased in the spleen and MLNs of rCsStefin-1 treated mice after DSS treatment. In conclusion, rCsStefin-1 could reduce the intestinal inflammation occurring after DSS treatment, these effects might be related with recruitment of IL-10 secreting macrophages.
Animals ; Antigens, Differentiation/analysis ; Clonorchis sinensis/*enzymology ; Colon/pathology ; Cystatins/*metabolism ; Cytokines/secretion ; Dextran Sulfate/toxicity ; Female ; Helminth Proteins/*metabolism ; Immunologic Factors/*metabolism ; Inflammation/chemically induced/*pathology ; Interleukin-10/analysis ; Intestines/*drug effects/pathology ; Lymph Nodes/immunology ; Macrophages/chemistry/*immunology ; Mice ; Mice, Inbred C57BL ; Severity of Illness Index ; Spleen/immunology

To determine the impact of IL-23 knockdown by RNA interference on the development and severity of ovalbumin (OVA)-induced asthmatic inflammation, and the potential mechanisms in mice, the IL-23-specific RNAi-expressing pSRZsi-IL-23p19 plasmid was constructed and inhaled into OVA-sensitized mice before each challenge, as compared with that of control mice treated with alum or budesonide. Inhalation of the pSRZsi-IL-23p19, significantly reduced the levels of OVA-challenge induced IL-23 in the lung tissues by nearly 75%, determined by RT-PCR. In addition, knockdown of IL-23 expression dramatically reduced the numbers of eosinophils and neutrophils in BALF and mitigated inflammation in the lungs of asthmatic mice. Furthermore, knockdown of IL-23 expression significantly decreased the levels of serum IgE, IL-23, IL-17, and IL-4, but not IFNgamma, and its anti-inflammatory effects were similar to or better than that of treatment with budesonide in asthmatic mice. Our data support the notion that IL-23 and associated Th17 responses contribute to the pathogenic process of bronchial asthma. Knockdown of IL-23 by RNAi effectively inhibits asthmatic inflammation, which is associated with mitigating the production of IL-17 and IL-4 in asthmatic mice.
Animals ; Asthma/chemically induced/genetics/metabolism/*prevention & control ; Bronchoalveolar Lavage Fluid/cytology ; Enzyme-Linked Immunosorbent Assay ; Eosinophils ; Female ; Inflammation/metabolism ; Interleukin-23/*genetics ; Leukocyte Count ; Mice ; Mice, Inbred BALB C ; Neutrophils ; Ovalbumin/pharmacology ; Plasmids/genetics ; *RNA Interference ; RNA, Small Interfering/*genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Th17 Cells/immunology