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1.
We investigated the effect of sofalcone, a synthetic flavonoid derivative of sophoradin, on tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 beta production in human monocytes stimulated by Helicobacter pylori water extract. H. pylori water extract significantly stimulated TNF-alpha and IL-1 beta production by monocytes while incubation with sofalcone (10 micrograms/ml and 50 micrograms/ml) significantly inhibited this increase in TNF-alpha and IL-1 beta production. These results suggest that sofalcone could be used to improve H. pylori-associated gastric mucosal inflammation through inhibition of proinflammatory cytokine production.  相似文献   

2.
In addition to phospholipase A2-I (PLA2-I) reported previously (ODA et al., 1991, Toxicon 29, 157), a new PLA2 named PLA2-II was isolated from Trimeresurus gramineus (green habu snake) venom, and its amino acid sequence was determined by sequencing the native protein and the peptides produced by enzymatic (Achromobacter protease I and clostripain) cleavages of the carboxamidomethylated derivative of the protein. The protein consisted of 122 amino acid residues and His-47, Asp-48, and Asp-98 which have been assumed to be essential for PLA2 activity were conserved. Its sequence similarity to PLA2-I was 79%, with 26 residual differences. In contrast to the unique presence of Phe-28 in PLA2-I, PLA2-II contains Tyr-28 as seen in most of other PLA2s. There was no significant difference between the dissociation constants of PLA2-I and PLA2-II for Ca2+. Secondary structure compositions of PLA2-II were similar to those of PLA2-I and Crotalus atrox PLA2. A striking difference was found between these isozymes in contractile activity of isolated smooth muscle preparation of guinea-pig ileum. PLA2-II was over ten times more potent than PLA2-I, although its lipolytic activity toward egg-yolk was even slightly weaker (73%) than that of PLA2-I. The difference in contractile activities of PLA2-I and PLA2-II could be assumed to be due to discriminative lipid recognition brought about by different amino acid residues at the 58th position (Asp for PLA2-I and Asn for PLA2-II).  相似文献   

3.
We investigated chemokine responses of human airway epithelial cells to transforming growth factor (TGF)-beta alone and in combination with tumor necrosis factor (TNF)-alpha or interferon (IFN)-gamma. TGF-beta selectively induced production of granulocyte-macrophage colony stimulating factor (GM-CSF) without significant coordinate expression of IL-8 or RANTES. TNF-alpha induced expression of both IL-8 and GM-CSF, without detectable production of RANTES. TGF-beta synergistically enhanced GM-CSF production with TNF-alpha, but suppressed production and release of IL-8. IFN-gamma induced RANTES production and release; TGF-beta synergistically enhanced RANTES release induced by IFN-gamma, but had no effect on RANTES mRNA production. Taken together, these data demonstrate that TGF-beta may play a pivotal role in the responsiveness of airway epithelial cells to chemotactic cytokines, by selectively enhancing GM-CSF and RANTES production while suppressing IL-8 production. This profile of chemokine responses promoted by TGF-beta would favor eosinophil, lymphocyte and monocyte recruitment, hallmarks of chronic and allergic inflammation, over neutrophil sequestration.  相似文献   

4.
To understand better the cellular and molecular mechanisms of chemical-induced occupational asthma, we examined the effects of the Th2 cytokine antagonists interferon-gamma (IFN-gamma), interleukin (IL)-12 and anti-IL-4 on the balance of the Th1/Th2 response induced by trimellitic anhydride (TMA) and phthalic anhydride (PA). Eight- to ten-week-old BALB/c mice were assigned to be exposed to either TMA or PA plus one of these Th2 cytokine antagonists. Both TMA (25% and 12.5% for sensitization and challenge, respectively) and PA (12.5% and 6.25% for sensitization and challenge, respectively) induced a Th2 response marked by an increasing production of IL-4 and IL-10 in the supernatants of ex vivo spleen cells cultured with concanavalin A and also of serum total IgE. Co-administration of IL-12 and antiIL-4 deviated these PA- or TMA-induced Th2 responses, as judged by an increasing serum total IgG2a production (up to 14-fold), associated with a slight decrease of IL-4 in three out of four experiments and of IL-10 in all four experiments. Co-administration of IFN-gamma, however, had only one weak effect. These findings suggest that the chemical-induced Th2-biased response may be diverted during an induction period by exogenous administration of the Th2 cytokine antagonists, particularly IL-12 and the anti-IL-4 antibody. These results would significantly enhance our understanding of the Th1/Th2 response induced by chemicals.  相似文献   

5.
Pirimiphos-methyl (O-2-diethylamino-6-methylpyrimidin-4-yl O,O-dimethyl phosphorothioate: POM) is widely used organophosphorous (OP) insecticide as a grain protectant to control insects during storage. This study was carried out to assess the immunologic effects of POM in Balb/c mice after 28-day oral exposure. Three dose levels of POM (10, 60, or 120 mg/kg/day) were administered orally to mice for 4 weeks. At autopsy after 28-day exposure, there were significant decreases in relative spleen weight and splenic cellularity found at 120 mg POM, but body weight, relative thymic weight, thymic cellularity, and splenic and thymic subsets were not affected. T cell proliferation response induced by Con A was significantly decreased at all dosages though no statistical differences were observed in splenic B cell proliferation. Significant increases in the production of cytokines (IL-2, IL-4, IL-6, IFN-gamma, and IL-10) were evident on the whole, but the increase in production of inflammatory cytokines overwhelmed that of the T(H)1 cell suppressive cytokine (IL-10). The relative levels of three types of autoantibodies, anti-dsDNA, anti-histone, and antinuclear antibody (ANA) were dose-dependently decreased in serum. Oral exposure to POM induced a significant decrease in Immunoglobulin M production capability in Balb/c mice. This decrease in antibody production capability may result from disturbances in cytokine balance produced by splenic immune cells. These results show that POM may induce allergic responses by relatively enhancing T(H)2 development and additionally contribute to chronic inflammation by attracting macrophage by IFN-gamma.  相似文献   

6.
The gold compounds, auranofin, sodium aurothiomalate, and triethyl gold phosphine have been demonstrated to inhibit various effector functions associated with monocyte-macrophage populations. Incubation of human peripheral blood monocytes and murine peritoneal macrophages with auranofin or triethyl gold phosphine inhibited TNF production in lipopolysaccharide [LPS] stimulated murine peritoneal macrophages. The inhibitory effect of auranofin and triethyl gold phosphine on LPS stimulated monokine production was reversible when these compounds were incubated with macrophage cultures at concentrations between 0.1-0.5 micrograms/ml. These compounds also inhibited both TNF and IL-1 production by human peripheral blood monocytes. Sodium aurothiomalate at these concentrations had no inhibitory effect on TNF or IL-1 production. Auranofin and triethyl gold phosphine also inhibited TNF production in vivo when compounds were administered orally or intraperitoneally 2 hours prior to a lethal dose of endotoxin. Serum TNF levels from Balb/c mice were significantly reduced when animals were predosed with 1-25 mg/kg of auranofin. The data suggest that the inhibition of TNF production by activated macrophages may contribute to the therapeutic role of gold compounds in the management of chronic inflammatory disease.  相似文献   

7.
Interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) have recently been added to the arsenal of synthetic biological response modifiers with important immunomodulatory activities. In this paper we have assessed the effects of acetylsalicylic acid (aspirin), thymosin alpha and thymosin fraction 5 (TF5), a partially purified calf thymic preparation, on production of IFN-gamma in vitro. Stimulation by oral aspirin of IL-2 and IFN-gamma production by peripheral blood lymphocytes (PBLs) was also studied in healthy human volunteers. Aspirin, thymosin alpha 1 and TF5 were all observed to enhance phytohemagglutinin (PHA)-stimulated production of IFN-gamma. Peak IFN-gamma production by PHA-stimulated PBLs was observed after 24 h of incubation with TF5 and after 72 h with aspirin. Stimulation by aspirin and TF5 required the presence of macrophages, and was additive and dose-dependent. The additive effects of aspirin and TF5 suggest that these agents act by different mechanisms. Oral administration of aspirin in normal volunteers significantly enhanced production of both IFN-gamma and IL-2. PHA-stimulated IFN-gamma production was greatest 24 h after aspirin ingestion; in contrast, IL-2 production was optimal 10 h after aspirin ingestion. These observations suggest that oral aspirin is an effective biological response modifier in humans and raise the possibility of a novel combination approach to immunomodulation involving cyclooxygenase inhibitors and thymosins.  相似文献   

8.
We have earlier reported that ethanolic extract of Boerhaavia diffusa, a plant used in Indian traditional system of medicine, significantly inhibits the cell proliferation. This led us to evaluate the immunomodulatory properties of this plant extract on various in vitro tests such as human natural killer (NK) cell cytotoxicity, production of nitric oxide (NO) in mouse macrophage cells, RAW 264.7, interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha), intracytoplasmic interferon-gamma (IFN-gamma) and expression of various cell surface markers on human peripheral blood mononuclear cells (PBMCs). Ethanolic extracts of B. diffusa roots inhibited human NK cell cytotoxicity in vitro, production of NO in mouse macrophage cells, IL-2 and TNF-alpha in human PBMCs. Intracytoplasmic IFN-gamma and cell surface markers such as CD16, CD25, and HLA-DR did not get affected on treatment with B. diffusa extract. Our study demonstrates immunosuppressive potential of ethanolic extract of B. diffusa.  相似文献   

9.
目的:探讨雷公藤单体雷公藤氯内酯醇(tripcholorolide,T4)对肺泡巨噬细胞(AM)炎症反应的影响及机制.方法:小鼠AM受脂多糖(LPS)10mg/L刺激的同时,加入T4 500 μg/L或地塞米松 100μmol/L;ELISA法测定上清液中TNFα、IL-1β、IL-6及IL-10浓度:RT-PCR检测上述因子及iNOS基因mRNA的表达.结果:AM受10 mg/L LPS刺激24小时后,上清液中TNFα、IL-1β、IL-6、IL-10及NO释放均明显增加.T4 500 μg/L及地塞米松100μmol/L对上述介质均有不同程度的抑制作用.LPS刺激5小时后,AM中TNFα、IL-6、IL-10和iNOS的mRNA表达均明显增加.T4和地塞米松对上述介质的mRNA表达均有明显抑制作用.另外,T4对TNFα、IL-6、IL-10 mRNA的稳定性无明显影响.结论:T4具有抑制AM中促炎介质和抗炎介质表达的作用.  相似文献   

10.
The thymic preparations thymosin fraction 5 (TF5) and synthetic thymosin alpha 1 (T alpha 1) were examined for their ability to enhance growth factor production by human peripheral blood mononuclear cells (PBMC). The results showed that both TF5 and T alpha 1 were capable of enhancing the production of a B cell growth factor (BCGF-12kD) and T cell growth factor (TCGF; IL-2). Enhancement by T alpha 1 could be obtained at 100-200-fold lower concentrations than that seen with TF5. In contrast, no enhancement of growth factor production was obtained with control preparations of non-thymic tissue extracts at any concentrations used. It was observed that stimulation of BCGF-12kD and IL-2 was most significantly obtained when the PBMC were activated with lectin. Furthermore, no direct effect of thymic hormones on test B and T cells was observed. These observations provide the first direct evidence that production of B cell growth factors can be enhanced by thymic hormones. In addition, these studies suggest that thymic hormones may regulate B cell responses by acting on mature activated T lymphocytes.  相似文献   

11.
Context: Mints (Lamiaceae) are used as traditional remedies for the treatment of several diseases. Their extracts are recognized as anti-inflammatory compounds.

Objective: This study characterized the cytotoxic effects of Mentha spicata L. (MS), Mentha pulegium L. (MP) and Mentha rotundifolia (L). Huds (MR) on macrophage cells (RAW264.7; U937) and determined their impact on apoptosis and autophagy, which can play a role in controlling inflammation.

Materials and methods: The extracts were prepared in culture medium and tested from 25 to 400?μg/mL after 24–48?h of treatment. To show the effect of the aqueous ethanol (50%) extracts on apoptosis and authophagy, the presence of cleaved caspase-3, and the conversion of LC3-I to LC3-II was evaluated by Western blotting.

Results: Compared with the MTT assay, crystal violet showed a pronounced decrease in the number of cells with all extracts at 48?h. Calculated IC50 values were 257.31, 207.82 and 368.02?μg/mL for MS, MP and MR, respectively. A significant increase in PI positive cells was observed with all extracts at 200-400?μg/mL. Mitochondrial dysfunctions and nuclear morphological changes were detected with MS and MR extracts at 400?μg/mL. At this concentration, no cleaved caspase-3 was found whereas stabilized caspase-3 in its dimeric form was identified. MS and MR extracts also favour LC3-I to LC3-II conversion which is a criterion of autophagy.

Conclusions: The cytotoxic profiles depend on the extracts considered; MS extract showed the strong activity. However, all the mint extracts studied interact with the apoptotic and autophagic pathways at elevated concentrations.  相似文献   

12.
We investigated the effects of Toki-shakuyaku-san and its crude ingredients in relation to the secretion of a cytokine-induced neutrophil chemoattractant, CINC/gro, interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF alpha) in the ovulatory process. Toki-shakuyaku-san significantly (p < 0.01) stimulated the secretion of 17 beta-estradiol but did not stimulate the secretion of progesterone in cultured whole ovarian dispersates. Toki-shakuyaku-san enhanced the secretion of CINC/gro in a dose-dependent manner and the production of CINC/gro at concentrations of 10 and 100 micrograms/ml of Toki-shakuyaku-san increased significantly (p < 0.01). Toki-shakuyaku-san also enhanced secretions of both IL-1 beta and TNF alpha, which are known to stimulate the secretion of CINC/gro in the ovulatory process. The production of TNF alpha increased significantly (p < 0.05) with 10 and 100 micrograms/ml of Toki-shakuyaku-san. Atractylodis Lanceae Rhizoma, Cnidii Rhizoma, Angelicae Radix, Paeoniae Radix and Alismatis Rhizoma, which are crude ingredients of Toki-shakuyaku-san, significantly (p < 0.01) enhanced the secretion of CINC/gro at concentrations of 100 micrograms/ml. The results of this study show that Toki-shakuyaku-san can stimulate the secretion of 17 beta-estradiol and stimulate the ovulatory process by stimulating the production of CINC/gro, IL-1 beta and TNF alpha in vitro. As a treatment for ovulatory disorders, Toki-shakuyaku-san may have stimulatory effects on both steroidogenesis and the ovulatory process.  相似文献   

13.
14.
The local lymph node assay (LLNA) is used to identify allergens by means of dermal exposure. For hazard identification, besides identification also the distinction between contact and respiratory allergens is of importance. We have previously shown that a modified LLNA can be used to identify respiratory allergens, on the basis of Con A induced IL-4 production. Here we show a good qualitative correlation between mRNA expression and production of IFN-gamma and IL-4. This suggests that distinction between contact and respiratory allergens may also be studied at the mRNA expression level. Secondly, another assay, similar to the modified LLNA but differing in the duration and the number of allergen applications as well as in the ex vivo culture conditions, here denoted as 'longer' assay, has been reported to be able to identify contact allergens, on the basis of (spontaneous) IFN-gamma production. In the present study we have compared these assays. Similar to our previous findings, in the modified LLNA exposure to the respiratory allergen trimellitic anhydride (TMA) resulted in a approximately 10-fold higher Con A induced IL-4 production compared with the contact allergen dinitrochlorobenzene (DNCB), while exposure to both allergens resulted in a similar Con A induced IFN-gamma production. In the 'longer' assay, TMA exposure resulted in Con A induced IL-4 production whereas DNCB exposure did not. Importantly, only a 2-fold higher spontaneous IFN-gamma production was induced by DNCB compared with TMA, the difference being not statistically significant. Thus, although the 'longer' assay indeed showed a somewhat higher IFN-gamma induction by DNCB compared with TMA, the magnitude and robustness of this effect question its applicability. These results favor the modified LLNA since it is shorter, and combines identification of allergens (by cell proliferation) with identification of respiratory allergens (by IL-4 production). Compounds that induce cell proliferation with a low concomitant IL-4 production may thus be identified as contact allergens, although the need to positively identity such allergens remain.  相似文献   

15.
As reported previously (Kosuge et al., Yakugaku Zasshi, 120, 408 (2000)), methyl gallate, a gallic acid derivative, which has been one of compounds isolated from extracts of Psidium geneus Myrtaceae, selectively suppresses Th2 cytokine secretion. In the present study, to examine more effective compounds than methyl gallate, the effects of various gallic acid derivatives on the secretion of helper T cell subtype specific cytokines from anti CD3-stimulated spleen cells were investigated. Ten micrograms/ml of methyl gallate and ethyl gallate remarkably suppressed the secretion of IL-4 and IL-5, Th2 cytokines, but did not suppress meaningfully the secretion of IFN-gamma, a Th1 cytokine. On the other hand, the other gallic acid derivatives suppressed the secretion of both IL-4 and IFN-gamma. Ten micrograms/ml of methyl gallate suppressed the secretion of IL-2, a Th1 cytokine, but the same concentration of ethyl gallate did not suppress it. In conclusion, it seemed that ethyl gallate was the most selective inhibitor for the secretion of Th2 cytokines among gallic acid derivatives used in this study.  相似文献   

16.
This study examined whether an extract of Cudrania tricuspidata shows anti-proliferative effects in anti-CD3/CD28-mediated spleen and CD4+CD25- T cells and decreases the production of the proinflammatory cytokines interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) in anti-CD3/CD28-mediated CD4+CD25- T cells. The proliferation of anti-CD3/CD28-mediated spleen cells and CD4+CD25- T cells was effectively suppressed by C. tricuspidata. This extract, however, did not show cytotoxicity in spleen cells under conditions where the antigen was not stimulated using CCK-8 analysis. C. tricuspidata also decreased the production of the pro-inflammatory cytokines IL-2 and IFN-gamma by selective inhibition of this extract on proliferating cells in anti-CD3/CD28-mediated CD4+CD25- T cells. These results suggest that C. tricuspidata may be useful in the treatment of autoimmune diseases and organ transplantation through the inhibitory action of T cells in inflammation.  相似文献   

17.
18.
Recombinant human tumor necrosis factor alpha (TNF alpha) decreases social exploration and induces weight loss in mice in a dose- and time-dependent manner (2.5-40 micrograms/mouse). To assess the role of interleukin-1 (IL-1) in these effects, mice pretreated with IL-1 receptor antagonist (IL-1ra, 500 micrograms/mouse, i.p.) were injected with 25 micrograms TNF alpha. Pretreatment with IL-1ra antagonized the depressive effects of TNF alpha on behaviour but only partially attenuated the weight loss induced by this cytokine. These results suggest that TNF alpha-induced sickness behaviour is mediated mainly by endogenously released IL-1 whereas metabolic changes are dependent on the release of other additional cytokines.  相似文献   

19.
Activated macrophages synthesize and release the potent polypeptides, interleukin-1 (IL-1) and tumor necrosis factor (TNF). In an effort to identify the cellular signals which control cytokine production by activated macrophages, we have developed an in vitro model employing the human THP-1 cell line. In the present study, THP-1 cells "primed" by 1.6 microM phorbol 12-myristate-13-acetate (TPA) for 4 hr demonstrated a dose- and time-dependent release of IL-1 beta and TNF upon activation by 20 micrograms/ml LPS. BSA/anti-BSA-coated latex beads were also a potent stimulus for IL-1 beta secretion. Moreover, the combination of a suboptimal concentration of LPS (200 ng/ml) plus interferon-gamma (0.03-333 U/ml) greatly enhanced IL-1 beta production. Resting THP-1 monocytes not "primed" by TPA did not secrete IL-1 beta or TNF. These distinct patterns of cytokine production may be related to the developmental stages of macrophage activation.  相似文献   

20.
Fraction number II obtained from Sephadex G-50 gel filtration of the soluble venom from the Brazilian scorpion Tityus serrulatus (TSV) stimulates macrophage function in vitro. The aim of this study was to identify which one of the several components of this fraction was responsible for the main stimulatory activity on macrophages. This component was identified as sub-fraction II-11, also known by the name of gamma toxin or simply abbreviated Ts1, which stands for toxin 1 of T. serrulatus venom. The effect of Ts1 was analyzed by detection of inflammatory mediators. Several functional bioassays were performed: TNF activity was assayed by measuring its cytotoxicity on L929 cells, whereas IL-1, IL-6, IFN-gamma and IL-10 were assayed by enzyme-linked immunosorbent assay. The levels of NO were evaluated by Griess colorimetric reactions in supernatants of macrophages in culture exposed to Ts1 and compared with FII. Macrophages exposed to Ts1 increase the production of mediators. With respect to the pro-inflammatory cytokines, an increment of IL-1alpha, IL-1beta was observed after 12 h; the maximum levels of IL-6 and TNF were observed after 24 h; the highest levels of IFN-gamma and NO were observed after 72 h. In contrast, the highest levels of anti-inflammatory cytokines such as IL-10 were observed after 120 h. With respect to the balance of pro- and anti-inflammatory cytokines, IL-1alpha/IL-10 and IL-6/IL-10 ratios appear incremented between 12 and 48 h in macrophages exposed to Ts1. IL-1beta/IL-10 and TNF/IL-10 ratios were increased in macrophages exposed to Ts1 for 12 h. IFN-gamma/IL-10 ratios increased up to 48 h, decaying thereafter. Elevated IL-6/TNF ratios were observed up to 24 h. These ratios may possibly reflect the inflammatory status during exposition to the venom. In conclusion, these data indicate that Ts1 has an important immunomodulatory effect on macrophages, and add important knowledge for understanding scorpion envenomation. It also opens the field for further research about the intoxication phenomenon as it is discussed here.  相似文献   

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