BACKGROUNDAlthough the onset of anemia during infectious disease is commonly correlated with production of inflammatory cytokines, the mechanisms by which cytokines induce anemia are poorly defined. This study focused on the mechanism research.

METHODSDifferent types of mice were infected perorally with Toxoplasma gondii strain ME49. At the indicated times, samples from each mouse were harvested, processed, and analyzed individually. Blood samples were analyzed using a Coulter Counter and red blood cell (RBC) survival was measured by biotinylation. Levels of tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), and inducible protein 10 (IP-10) mRNA in liver tissue were measured by real-time polymerase chain reaction.

RESULTST. gondii-infected mice exhibited anemia due to a decrease in both erythropoiesis and survival time of RBC in the circulation (P < 0.02). In addition, infection-stimulated anemia was associated with fecal occult, supporting previous literature that hemorrhage is a consequence of T. gondii infection in mice. Infection-induced anemia was abolished in interferon gamma (IFNγ) and IFNγ receptor deficient mice (P < 0.05) but was still evident in mice lacking TNF-α, iNOS, phagocyte NADPH oxidase or IP-10 (P < 0.02). Neither signal transducer and activator of transcription 1 (STAT1) deficient mice nor 129S6 controls exhibited decreased erythropoiesis, but rather suffered from an anemia resulting solely from increased loss of circulating RBC.

CONCLUSIONSInfection-stimulated decrease in erythropoiesis and losses of RBC have distinct mechanistic bases. These results show that during T. gondii infection, IFNγ is responsible for an anemia that results from both a decrease in erythropoiesis and a STAT1 independent loss of circulating RBC.

Anemia ; genetics ; metabolism ; Animals ; Erythrocytes ; pathology ; Interferon-gamma ; metabolism ; Male ; Mice ; Mice, Knockout ; Nitric Oxide Synthase Type II ; genetics ; metabolism ; Receptors, Interferon ; genetics ; metabolism ; STAT1 Transcription Factor ; genetics ; metabolism ; Toxoplasma ; pathogenicity ; Tumor Necrosis Factor-alpha ; genetics ; metabolism

OBJECTIVEThe study was aimed to investigate the inhibitory effect and mechanism of astragaloside IV (ASI) on the activation of microglial cells.

METHODAfter pre-incubated with ASI for 2 h, microglial cells BV-2 were stimulated with interferon-γ (IFN-γ) for 1. 5 h and 24 h, respectively. Secretion of nitric oxide (NO) in the medium was measured by Griess method. Production of tumor necrosis factor alpha (TNF-α) was detected by ELISA approach. Cellular gene expressions of CD11b, TNF-α, interleukin 1β (IL-1β) and induced nitric oxide synthase (iNOS) were examined by quantitative-PCR analysis. Total and phosphorylation of STAT1, IκB and NF-κB was analyzed by Western blot method.

RESULTASI could significantly inhibit the increased secretion of TNF-α and NO from BV-2 cells upon IFN-γ stimulation (P < 0.001). Further study showed that ASI significantly down-regulated gene expression of IL-1β and TNF-α (P < 0.01, P < 0.05) and exhibited a trend to reduce that of iNOS. IFN-γ and ASI have no obvious effect on gene expression of CD11b. Moreover, ASI inhibited the phosphorylation of STAT1, IκB and NF-κB elicited by IFN-γ stimulation.

CONCLUSIONASI could restrain microglial activation through interfering STAT1/IκB/NF-κB signaling pathway, reducing gene expres- sion of IL-1β and TNF-α, and thus inhibiting the production of proinflammatory mediators such as NO and TNF-α.

Animals ; Astragalus Plant ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; I-kappa B Proteins ; genetics ; metabolism ; Interferon-gamma ; genetics ; metabolism ; Mice ; NF-kappa B ; genetics ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type II ; genetics ; metabolism ; STAT1 Transcription Factor ; genetics ; metabolism ; Saponins ; pharmacology ; Signal Transduction ; drug effects ; Triterpenes ; pharmacology

BACKGROUND/AIMS: Microscopic colitis is characterized by chronic watery diarrhea with specific pathological changes that can be diagnosed by microscopic examination. We performed immunohistochemical analysis of proinflammatory cytokines to investigate the pathogenic mechanism of microscopic colitis. METHODS: This study consisted of six patients with lymphocytic colitis, six patients with collagenous colitis, and six patients with functional diarrhea but normal pathology. We performed an immunohistochemical analysis of the colonic mucosal biopsies to assess the expression of cyclo-oxygenase-2, interleukin-17, nuclear factor-kappaB, interferon-gamma, inducible nitric oxide synthase, and tumor necrosis factor-alpha. We compared the quantity score of immunohistochemical staining among the groups. RESULTS: The microscopic colitis group showed significantly higher expression of cyclo-oxygenase-2, interleukin-17, nuclear factor-kappaB, and interferon-gamma compared with the control group. Cytokine expression was similar between collagenous colitis and lymphocytic colitis. However, the expression of cyclo-oxygenase-2 was higher in collagenous colitis. CONCLUSIONS: Proinflammatory cytokines, including interleukin-17 and interferon-gamma, are highly expressed in microscopic colitis. The expression of cyclo-oxygenase-2 was higher in collagenous colitis than in lymphocytic colitis. This study is the first on interleukin-17 expression in microscopic colitis patients.
Biopsy ; Colitis, Microscopic/*metabolism ; Colon/pathology ; Cyclooxygenase 2/*metabolism ; Cytokines/metabolism ; Diarrhea/metabolism ; Humans ; Interferon-gamma/metabolism ; Interleukin-17/*metabolism ; Intestinal Mucosa/pathology ; NF-kappa B/metabolism ; Nitric Oxide Synthase Type II/*metabolism ; Tumor Necrosis Factor-alpha/metabolism

A novel Pleurotus nebrodensis polysaccharide (PN-S) was purified and characterized, and its immune-stimulating activity was evaluated in RAW264.7 macrophages. PN-S induced the proliferation of RAW264.7 cells in a dose-dependent manner, as determined by the MTT assay. After exposure to PN-S, the phagocytosis of the macrophages was significantly improved, with remarkable changes in morphology being observed. Flow cytometric analysis demonstrated that PN-S promoted RAW264.7 cells to progress through S and G2/M phases. PN-S treatment enhanced the productions of interleukin-6 (IL-6), nitric oxide (NO), interferon gamma (INF-γ), and tumor necrosis factor-α (TNF-α) in the macrophages, with up-regulation of mRNA expressions of interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), interferon gamma(INF-γ) and tumor necrosis factor-α (TNF-α) being observed in a dose-dependent manner, as measured by qRT-PCR. In conclusion, these results suggest that the purified PN-S can improve immunity by activating macrophages.
Animals ; Cell Cycle ; immunology ; Cell Line ; Cell Proliferation ; drug effects ; Fungal Polysaccharides ; pharmacology ; Immunity ; drug effects ; Interferon-gamma ; biosynthesis ; metabolism ; Interleukin-6 ; biosynthesis ; metabolism ; Macrophages ; immunology ; metabolism ; Mice ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase Type II ; metabolism ; Pleurotus ; RNA, Messenger ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Necrosis Factor-alpha ; biosynthesis ; metabolism ; Up-Regulation

In the present study, the effects of Pleurotus nebrodensis polysaccharide (PN-S) on the immune functions of immunosuppressed mice were determined. The immunosuppressed mouse model was established by treating the mice with cyclophosphamide (40 mg/kg/2d, CY) through intraperitoneal injection. The results showed that PN-S administration significantly reversed the CY-induced weight loss, increased the thymic and splenic indices, and promoted proliferation of T lymphocyte, B lymphocyte, and macrophages. PN-S also enhanced the activity of natural killer cells and increased the immunoglobulin M (IgM) and immunoglobulin G (IgG) levels in the serum. In addition, PN-S treatment significantly increased the phagocytic activity of mouse peritoneal macrophages. PN-S also increased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), and nitric oxide (NOS) in splenocytes. qRT-PCR results also indicated that PN-S increased the mRNA expression of IL-6, TNF-α, INF-γ, and nitric oxide synthase (iNOS) in the splenocytes. These results suggest that PN-S treatment enhances the immune function of immunosuppressed mice. This study may provide a basis for the application of this fungus in adjacent immunopotentiating therapy against cancer and in the treatment of chemotherapy-induced immunosuppression.
Animals ; Antineoplastic Agents, Alkylating ; Biological Products ; pharmacology ; therapeutic use ; Cell Line ; Cyclophosphamide ; Immunity ; drug effects ; Immunologic Factors ; pharmacology ; therapeutic use ; Immunosuppression ; Interferon-gamma ; metabolism ; Interleukin-6 ; metabolism ; Macrophages ; drug effects ; metabolism ; Male ; Mice, Inbred BALB C ; Neoplasms ; drug therapy ; immunology ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Phagocytosis ; drug effects ; Pleurotus ; chemistry ; Polysaccharides ; pharmacology ; therapeutic use ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo study possible immunobiological potential of Osmunda japonica Thunb.

METHODSImmunomodulatory effects of ethanol extracts prepared from rhizomes of O. japonica and phenolic compounds isolated from the extracts were investigated under the in vitro conditions using the rat peritoneal cells (2×10(6)/mL; 24 h culture). Biosynthesis of nitric oxide (NO) was assayed by Griess reagent, production of prostaglandin E2 (PGE2) and secretion of cytokines were determined by enzyme-linked immunoabsorbent assay.

RESULTSThe extracts activated dose dependently, with the onset at 2.5-5 μmol/L concentrations, the high output NO production, and secretion of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). Mild enhancement of NO was produced by the aldehyde-type phenolics 4-hydroxybenzaldehyde and 3,4-hydroxybenzaldehyde. In contrasts, the acetone-type phenolics 4-hydroxybenzalacetone and 3,4-hydroxybenzalacetone inhibited production of immune mediators including cytokines (TNF-α, IL-1β, IL-6), NO, and PGE2. The 3,4-hydroxybenzalacetone was more effective than 4-hydroxybenzaldehyde. The IC50s estimates ranged within the interval of 5-10 μmol/L. No signs of cytotoxicity were observed up to the 50 μmol/L concentration of the compounds.

CONCLUSIONPhenolic compounds contained in medicinal herb Osmunda japonica possess distinct immunomodulatory activity.

Animals ; Cell Survival ; drug effects ; Cells, Cultured ; Dinoprostone ; biosynthesis ; Female ; Ferns ; chemistry ; Immunologic Factors ; pharmacology ; Interferon-gamma ; pharmacology ; Lipopolysaccharides ; pharmacology ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase Type II ; genetics ; metabolism ; Peritoneum ; cytology ; drug effects ; Phenols ; chemistry ; isolation & purification ; pharmacology ; Plant Extracts ; chemistry ; isolation & purification ; pharmacology ; Polymyxin B ; pharmacology ; Proline ; analogs & derivatives ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Thiocarbamates ; pharmacology

OBJECTIVETo investigate the effect of interferon regulatory factors (IRFs) on neointimal formation after vascular injury in the mouse, and its possible mechanism.

METHODSVascular injury was induced by polyethylene cuff placement around the left femoral artery of IRF-1-deficient mice and C57BL/6J mice. The mRNA expressions of IRF-1, IRF-2, angiotensin II type 2 (AT2) receptor, interleukin-1 beta converting enzyme (ICE), inducible nitric oxide synthase (iNOS) were detected by RT-PCR and immunohistochemical staining.

RESULTSNeointimal formation after vascular injury was significantly greater in IRF-1-deficient mice than that in C57BL/6J mice (P<0.05). In contrast, TUNEL-positive nuclei to total nuclei in the neointima and media in vascular smooth muscle cell (VSMC) in the injured artery significantly attenuated in IRF-1-deficient mice compared to C57BL/6J mice (P<0.05). The expressions of AT2 receptor as well as pro-apoptotic genes such as ICE and iNOS in C57BL/6J mice were up-regulated in response to vascular injury, but this upregulation was attenuated in IRF-1-deficient mice.

CONCLUSIONSOur results suggest that IRF-1 induces VSMC apoptosis and inhibits neointimal formation after vascular injury at least partly due to the upregulation of AT2 receptor, ICE and iNOS expressions. These results indicate that IRF-1 exerts an inhibitory effect on neointimal formation through the induction of apoptosis in VSMCs.

Animals ; Apoptosis ; physiology ; Caspase 1 ; genetics ; metabolism ; Femoral Artery ; anatomy & histology ; pathology ; Interferon Regulatory Factor-1 ; genetics ; metabolism ; Interferon Regulatory Factor-2 ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Muscle, Smooth, Vascular ; cytology ; metabolism ; pathology ; Nitric Oxide Synthase Type II ; genetics ; metabolism ; Platelet Endothelial Cell Adhesion Molecule-1 ; genetics ; metabolism ; Receptor, Angiotensin, Type 2 ; genetics ; metabolism ; Tunica Intima ; pathology ; physiology

The aim of this study was to evaluate the therapeutic potential of bone marrow mesenchymal stem cells (MSC) on acute liver injury induced by concanavalin A (ConA). MSCs were isolated from male C57BL/6 mice and cultured, and a ConA-induced acute liver injury model was used. MSCs were systemically infused immediately after mice were challenged with ConA, control mice received only saline infusion. 24 hours after MSC transplantation, the level of serum aminotransferases, histologic change and in situ apoptosis of cells were detected, the expression of inflammatory mediators were examined by real-time RT-PCR. The results indicated that MSC transplantation significantly reduced ConA-induced acute liver injury, including the decrease of the level of serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST) and the extenuation of liver necrosis and in situ apoptosis. Furthermore, after MSC infusion the expression of TNF-alpha, IFN-gamma in liver decreased greatly (p<0.05) with no statistical difference in the expression of iNOS, IL-2 and IL-10 (p>0.05). It is concluded that the systemic infusion of MSCs can alleviate ConA induced acute liver injury in mice.
Animals ; Bone Marrow Cells ; cytology ; Chemical and Drug Induced Liver Injury ; therapy ; Concanavalin A ; adverse effects ; Interferon-gamma ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-2 ; metabolism ; Liver ; pathology ; Male ; Mesenchymal Stem Cell Transplantation ; Mice ; Mice, Inbred C57BL ; Nitric Oxide Synthase Type II ; metabolism ; Treatment Outcome ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo study the regulatory effect of fengshiqing (FSQ) on interleukin 4 (IL-4), gamma-interferon (gamma-IFN), macrophage inflammatory protein 1alpha (MIP-1alpha) and collagen type II antibody (C II Ab) in serum and supernatant of synovial cell culture of rat with rheumatoid arthritis (RA), to explore the mechanism of action of clearing-heat and activating blood method for treatment of RA.

METHODSRA rat model was induced by C II Ab combined with Freund's complete adjuvant, and the levels of IL-4, gamma-IFN, MIP-1alpha and C II Ab in serum and supernatant of synovial cell were detected by ELISA.

RESULTSAs compared with the normal group, serum level of C II Ab in the model group was significantly higher (P < 0.01), serum and supernatant contents of IL-4 on the 14th and 28th day of modeling were lower and those of gamma-IFN and MIP-1alpha were higher, the difference showed statistical significance (P < 0.05 or P < 0.01). After being treated with FSQ and IL-4 contents in serum and supernatant as well as MIP-1alpha in supernatant restored on the 14th day (P < 0.05 or P < 0.01), while all the indexes restored on the 28th day.

CONCLUSIONFSQ could evidently up-regulate the level of IL-4 and down-regulate that of MIP-1alpha in serum and local synovial membrane in RA rats, and shows a suppressive trend of gamma-IFN, so as to maintain the Th1/Th2 equilibrium, suppress the cellular and humoral immune response in the local synovial membrane, and alleviate the chronic changes of arthritis, synovitis and vasculitis.

Animals ; Arthritis, Rheumatoid ; metabolism ; Chemokine CCL3 ; metabolism ; Collagen Type II ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Female ; Interferon-gamma ; metabolism ; Interleukin-4 ; metabolism ; Male ; Rats ; Rats, Wistar ; Th1-Th2 Balance

We demonstrated previously that Coptidis rhizoma extract (CRE) prevented S-nitroso-N-acetylpenicillamine-induced apoptotic cell death via the inhibition of mitochondrial membrane potential disruption and cytochrome c release in RINm5F (RIN) rat insulinoma cells. In this study, the preventive effects of CRE against cytokine-induced beta-cell death was assessed. Cytokines generated by immune cells infiltrating pancreatic islets are crucial mediators of beta-cell destruction in insulin-dependent diabetes mellitus. The treatment of RIN cells with IL-1beta and IFN-gamma resulted in a reduction of cell viability. CRE completely protected IL-1beta and IFN-gamma-mediated cell death in a concentration-dependent manner. Incubation with CRE induced a significant suppression of IL-1beta and IFN-gamma-induced nitric oxide (NO) production, a finding which correlated well with reduced levels of the iNOS mRNA and protein. The molecular mechanism by which CRE inhibited iNOS gene expression appeared to involve the inhibition of NF-kappa B activation. The IL-1beta and IFN-gamma-stimulated RIN cells showed increases in NF-kappa B binding activity and p65 subunit levels in nucleus, and IkappaBalpha degradation in cytosol compared to unstimulated cells. Furthermore, the protective effects of CRE were verified via the observation of reduced NO generation and iNOS expression, and normal insulin-secretion responses to glucose in IL-1beta and IFN-gamma-treated islets.
Animals ; Cell Death/drug effects ; Cell Line ; Cell Nucleus/metabolism ; Cell Survival/drug effects ; Drugs, Chinese Herbal/*pharmacology ; Gene Expression Regulation, Enzymologic/drug effects ; Glucose/pharmacology ; I-kappa B Proteins/metabolism ; Insulin/secretion ; Insulin-Secreting Cells/*cytology/*drug effects/enzymology ; Interferon-gamma/*pharmacology ; Interleukin-1beta/*pharmacology ; Male ; NF-kappa B/*metabolism ; Nitric Oxide/biosynthesis ; Nitric Oxide Synthase Type II/genetics/metabolism ; Protein Transport/drug effects ; RNA, Messenger/genetics/metabolism ; Rats ; Rats, Sprague-Dawley