Ethanolic extract and water-soluble polysaccharide from Chaenomeles speciosa fruit modulate lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophage cells

Ethnopharmacological relevance

Chaenomeles speciosa fruits have been widely used in traditional Chinese medicine for treatment of diseases related to inflammatory reaction. This study aims to identify anti-inflammatory and immunomodulatory components of Chaenomeles speciosa fruit and unravel their potential mechanisms.

Materials and methods

Ethanolic extract and its n-hexane, chloroform, ethyl acetate and n-butanol fractions, as well as water-soluble polysaccharide, were prepared from dry fruits of Chaenomeles speciosa. The mouse macrophage-like RAW264.7 cells were induced by lipopolysaccharide (LPS) and used as an inflammatory cell model. Production of nitric oxide in the cells was determined by the Griess assay, and cell viability was tested by the MTT method. Cellular apoptosis was evaluated by fluorescence-activated cell sorting. Relative quantification of inflammation-related genes was analyzed by real-time PCR.

Results

LPS-induced production of nitric oxide in RAW264.7 cells was significantly inhibited by the ethyl acetate fraction (EAF) at 200–800 μg/ml, while Chaenomeles speciosa polysaccharide (CPS) promoted nitric oxide production at 250–750 μg/ml either alone or in an additive fashion with LPS. Both EAF and CPS did not provoke noticeable cytotoxicity and apoptosis at the above effective concentrations. EAF significantly reduced LPS-induced upshift of iNOS mRNA level but showed no significant effect on the induction of IFN-γ and G-CSF, while CPS reduced the gene induction of TNF-α, IFN-γ and G-CSF by LPS.

Conclusions

EAF was able to inhibit nitric oxide production by reducing LPS-induced upshift of iNOS mRNA level. CPS was an activator of nitric oxide production through cytokines such as TNF-α, IFN-γ and G-CSF. These results demonstrate the therapeutic effects of both ethanolic and aqueous extracts of Chaenomeles speciosa fruit, a traditional edible medicine used in health maintenance and disease treatment.     

Anti-inflammatory effects of Z23 on LPS-induced inflammatory responses in RAW264.7 macrophages

Aim of the study

Fissistigma oldhamii (Hemsl.) Merr, a traditional Chinese herb medicine, is used for treating rheumatoid arthritis in China. In our previous study, an effective compound, 7′-(3′,4′-dihydroxyphenyl)-N-[(4-methoxyphenyl) ethyl] propenamide (Z23), from this herb has showed potent immunosuppressive effects both in vitro and in vivo. However, its anti-inflammatory effect and mechanism is still need to explore.

Materials and methods

We examined the in vitro effects of Z23 on the production of nitric oxide (NO), prostaglandin E2 (PGE2) and cytokines by lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.

Results

Z23 significantly decreased the production of PGE2, NO, tumour necrosis factor alpha (TNFalpha) and IL6 production. Inducible nitric oxide synthase (iNOS) and cyclooxygenase2 (COX2) gene expression were also significantly reduced.

Conclusions

These results demonstrated that Z23 exerted an anti-inflammatory effect through modulating the synthesis of several mediators and cytokines involved in the inflammatory process. This study provided evidence to understand the therapeutic effects of Fissistigma oldhamii (Hemsl.) Merr and indicated that Z23 has the potential for treatment of various inflammatory diseases where the overproduction of NO, PGE2 and inflammatory cytokines has been shown to play a role, e.g. rheumatoid arthritis.     

桂皮醛通过下调mPGES-1和COX-2抑制IL-1β 诱导的RAW264.7细胞PGE2分泌

目的:在明确桂皮醛通过下调COX-2抑制PGE2生成的基础上,进一步探讨其抑制PGE2生成的机制。方法:采用IL-1β刺激的方法,构建炎症模型,并用ELISA法检测PGE2的分泌量,用Real-time PCR法检测mPGES-1和COX-2 mRNA的表达,用Western blotting法检测mPGES-1蛋白,以观测桂皮醛对上述指标的影响。结果:桂皮醛能显著抑制PGE2的分泌,同时,也能显著下调mPGES-1和COX-2 mRNA的表达,及mPGES-1蛋白的表达。结论:桂皮醛对RAW264.7细胞PGE2生成的影响,除通过对COX-2的抑制作用外,也要归因于其对mPGES-1的抑制作用。     

Inhibitory phenolic amides on lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells from Beta vulgaris var. cicla seeds

Four phenolic compounds were isolated from Beta vulgaris L. var. cicla L. (Chenopodiaceae). These isolated compounds were identified as N-cis-feruloyl 3-O-methyldopamine (1), N-cis-feruloyl tyramine (2), N-trans-feruloyl 3-O-methyldopamine (3), N-trans-feruloyl tyramine (4), respectively, by spectroscopic analysis. The phenolic amides 1-4 exhibited modest inhibitory activity on LPS-activated nitric oxide production dose-dependently in RAW 264.7 cells.     

芳香新塔花总黄酮对脂多糖诱导的RAW264.7细胞分泌炎症因子的影响及机制

目的观察芳香新塔花总黄酮(ZCF)对脂多糖(LPS)诱导的小鼠单核/巨噬细胞系RAW264. 7细胞炎症模型中炎症因子的影响及机制。方法采用LPS刺激RAW264. 7细胞,建立细胞炎症模型。以MTT法检测不同浓度芳香新塔花总黄酮对RAW264. 7细胞的毒性作用。芳香新塔花总黄酮和阿托伐他汀钙(阳性药物)预处理,观察各组细胞的形态,以Griess法检测NO的含量,以酶联免疫吸附试验检测细胞上清中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)的含量,实时荧光定量PCR(qRT-PCR)测定TLR4和NF-κB p65 mRNA的表达。结果1μg/m L LPS刺激RAW264. 7细胞24 h,可成功构建炎症细胞模型。芳香新塔花总黄酮在1~100μg/m L浓度范围内对RAW264. 7细胞无显著的细胞毒性。LPS刺激RAW264. 7细胞后,细胞体积明显增大,形态不规则,伸出大量的伪足,而阿托伐他汀钙和芳香新塔花总黄酮干预后,RAW264. 7细胞变小,触角减少,形态较规则。脂多糖可明显诱导RAW264. 7细胞分泌NO、TNF-α、IL-1β和IL-6(P <0. 01),TLR4和NF-κB p65 mRNA表达增高,而芳香新塔花总黄酮和阿托伐他汀钙可使NO、TNF-α、IL-1β和IL-6的释放受到抑制(P <0. 05,P <0. 01)。芳香新塔花总黄酮和阿托伐他汀钙预处理可使TLR4和NF-κB p65 mRNA的表达降低(P <0. 05,P <0. 01)。结论芳香新塔花总黄酮可抑制LPS诱导的RAW264. 7细胞炎症反应,下调NO、TNF-α、IL-1β和IL-6的表达,其机制可能与其抑制TLR4/NF-κB信号转导通路的激活有关。     

黄芪对IgA肾病小鼠肾脏功能和肾组织蛋白质表达的作用

目的：研究右旋糖苷所致IgA肾病小鼠的肾组织蛋白表达变化和黄芪提取物（AEAR）对IgA肾病小鼠的作用。方法：给正常小鼠注射右旋糖苷建立IgA肾病小鼠模型。部分模型小鼠给予AEAR10g-kg^-1·d^-1。作为AEAR治疗组。为探究AEAR的作用,运用双向电泳（2-DE）技术分别获得正常对照组、IgA肾病模型组、AEAR组小鼠的肾组织蛋白凝胶,银染后,图像用PDQUEST双维分析软件分析比较,得到相应图谱。结果：连续12周给予AEAR的IgA肾病小鼠血清尿素氮（BUN）、肌酐（Cr）和尿蛋白含量明显降低,且它们的肾组织蛋白图谱相应恢复接近正常鼠的图谱形态。与正常组比较,模型组有334个蛋白表达有显著性差异,其中142个蛋白表达增强2倍,61个蛋白表达增强5倍,121个蛋白表达减弱2倍;10个蛋白在模型组特异表达,在正常组不表达。以上334个差异蛋白中的50％个蛋白在给予AEAR治疗后,表达水平趋近于正常对照组水平;上述10个特异表达的蛋白经过AEAR干预后,有5个蛋白恢复至正常的不表达状态,4个蛋白表达明显减弱接近正常水平,只有1个蛋白表达上调甚至高于模型组对应蛋白的表达水平,分析可能与IgA肾病发病或AEAR药物作用密切相关。结论：AEAR不仅具有保护IgA肾病小鼠肾脏功能的作用,而且能调节小鼠肾脏组织蛋白表达,有助于发现AEAR作用于IgA肾病的靶蛋白。     

Inhibitory effect of sulphated polysaccharide porphyran (isolated from Porphyra yezoensis) on RANKL‐induced differentiation of RAW264.7 cells into osteoclasts

Safe and efficient therapeutic agents for bone diseases are required in natural sources. We previously found that edible seaweed‐derived polysaccharide porphyran exhibited anti‐inflammatory effects through the down regulation of nuclear factor‐κB. The aim of this study was to investigate the availability of porphyran as a therapeutic agent for bone diseases. The effects of porphyran on receptor activator of nuclear factor κB ligand (RANKL)‐induced osteoclastogenesis in RAW264.7 cells were examined. Porphyran suppressed RANKL‐induced osteoclast formation in a concentration‐dependent manner (6.25–50 μg/ml) without any cytotoxic effects. Furthermore, real‐time polymerase chain reaction analyses indicated that porphyran at 50 μg/ml significantly attenuated the RANKL‐induced increase in the mRNA levels of osteoclastogenesis‐related marker genes such as nuclear factor of activated T cells, tartrate‐resistant acid phosphatase, cathepsin K, and matrix metalloproteinase‐9 in RAW264.7 cells. To our knowledge, this is the first report showing that edible‐seaweed‐derived polysaccharide porphyran can suppress RANKL‐induced osteoclastogenesis. Our results suggest that porphyran can be used as a safe therapeutic agent to improve osteoclast‐related pathological conditions.     

羌活中的香豆素类成分及其抑制脂多糖诱导的RAW 264.7细胞NO生成活性的研究

目的研究羌活Notopterygium incisum的香豆素类成分及其抗炎活性。方法采用硅胶、HPLC等柱色谱方法进行分离纯化,通过质谱、核磁共振波谱数据鉴定化合物的结构;采用脂多糖(LPS)诱导的小鼠巨噬细胞RAW 264.7炎症反应模型,考察羌活中香豆素类成分对炎症反应模型一氧化氮(NO)生成的影响。结果从羌活甲醇提取物分离得到24个香豆素类化合物,分别鉴定为异欧前胡素(1)、川白芷素(2)、补骨脂素(3)、香柑内酯(4)、茵陈素(5)、欧芹酚(6)、5-去氢羌活醇(7)、环氧脱水羌活醇(8)、7″-O-甲基异羌活醇(9)、佛手柑素(10)、7-异戊烯氧基-6-甲氧基-香豆素(11)、栓翅芹烯醇(12)、羌活醇(13)、去甲呋喃羽叶芸香素(14)、异羌活醇(15)、蛇床夫内酯(16)、6-异戊烯氧基伞形花内酯(17)、紫花前胡苷元(18)、异虎耳草素(19)、紫花前胡苷(20)、前胡苷V(21)、前胡苷I(22)、印枳苷元-11-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖苷(23)、羌活苷(24)。化合物7～10、13和15抑制LPS诱导的RAW 264.7细胞NO生成活性最强,最大半数抑制浓度(IC_(50))值为8.50～35.12μmol/L。结论化合物7为新的天然产物,化合物17为首次从羌活中分离得到;C-5位上具有多烯烃结构的香豆素抑制LPS诱导的RAW 264.7细胞NO生成活性较强。     

单因素考察和正交试验结合优选黄芪药材蛋白质提取工艺

目的:优选黄芪药材可溶性蛋白质的最佳提取工艺。方法:对黄芪药材蛋白质提取条件进行单因素考察,并采用L9(34)正交试验设计法,采用考马斯亮蓝染色法,以黄芪药材可溶性蛋白质含量为指标,考察料液比、pH值、提取温度、提取时间四个因素对可溶性蛋白质提取率的影响,从而确定黄芪药材蛋白质的最佳提取工艺。结果:建立了黄芪药材蛋白质的最佳提取工艺:向黄芪药材粉末中加入20倍量pH为12的蒸馏水,在温度30℃条件下回流提取10 min。结论:优化的提取工艺稳定、合理、可行,能正确反映黄芪药材中的蛋白质含量,为黄芪生物活性物质的进一步研究提供了实验依据。     

Enhanced expression of inducible nitric oxide synthase by Juzen-taiho-to in LPS-activated RAW264.7 cells, a murine macrophage cell line

We have investigated the effect of Juzen-taiho-to (TJ-48) on inducible NO synthase (iNOS) expression and nitric oxide (NO) production in RAW264.7 cells, a murine macrophage cell line. TJ-48-lipopolysaccharide (LPS) combination induced iNOS mRNA expression earlier, stronger and remained longer that paralleled but with a higher NO production compared to LPS stimulation. TJ-48 itself showed no inducible effect either on NO production or iNOS mRNA expression. This phenomenon could be considered to contribute, at least in part, to the beneficial effects of TJ-48 through the iNOS-mediated activation of biodefense mechanism.     

Effects of compounds from Kaempferia parviflora on nitric oxide, prostaglandin E2 and tumor necrosis factor-alpha productions in RAW264.7 macrophage cells

Kaempferia parviflora Wall. ex Baker, is one of the plants in the Zingiberaceae family, locally known in Thai as kra-chai-dam. The rhizome of this plant has been used for treatment of gout, apthous ulcer and abscesses. Since K. parviflora rhizomes have long been used for treatment of inflammation and possessed marked nitric oxide (NO) inhibitory activity (IC(50)=7.8microg/ml), we thus investigated the inhibitory activity of compounds isolated from this plant against lipopolysaccharide (LPS)-induced NO release in RAW264.7 cells. From bioassay-guided fractionation of K. parviflora, seven methoxyflavones were isolated from the hexane fraction and were tested for their anti-inflammatory effects. Among the isolated compounds, compound 5 (5-hydroxy-3,7,3',4'-tetramethoxyflavone) exhibited the highest activity against NO release with an IC(50) value of 16.1microM, followed by 4 (IC(50)=24.5microM) and 3 (IC(50)=30.6microM). Compound 5 was also tested on LPS-induced prostaglandin E(2) (PGE(2)) and tumor necrosis factor-alpha (TNF-alpha) releases from RAW264.7 cells. It was revealed that 5 showed appreciable inhibitory effect on PGE(2) release (IC(50)=16.3microM), but inactive on TNF-alpha (IC(50)>100microM). These findings may support the use in Thai traditional medicine of K. parviflora for treatment of inflammatory-related diseases through the inhibition of NO and PGE(2) releases but partly due to that of TNF-alpha.     

大豆素与葛根素抑制LPS 诱导RAW264.7细胞NO 产生的活性比较

目的：比较分析大豆素与葛根素体外抗氧化及抑制NO、NOS活性机制。方法：用1滋g·mL-1 LPS诱导体外培养的RAW264.7细胞,制备呼吸爆发、自由基反应模型。采用MTT法检测大豆素及葛根素的细胞毒性;采用DCFH-DA探针及激光共聚焦显微镜观察被试药的抗氧化能力;采用Griess法检测细胞培养体系中NO水平;采用化学比色法测定细胞内T-NOS含量。结果：大豆素与葛根素均能显著抑制LPS诱导RAW264.7细胞NO释放及T-NOS表达。结论：大豆素与葛根素的抗氧自由基活性接近,有望作为葛根素的替代品使用。     

Suppressive effect of inducible nitric oxide synthase (iNOS) expression by the methanol extract of Actinodaphne lancifolia

Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) has played a crucial role in various pathophysiological processes including inflammation and carcinogenesis. Therefore, the inhibitors of NO synthesis or iNOS gene expression have been considered as potential anti-inflammatory and cancer chemopreventive agents. In our continuous search for iNOS inhibitors from natural products we have evaluated indigenous Korean plant extracts using an assay for inhibition of nitric oxide formation on lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. As a result, the methanolic stem extract of Actinodaphne lancifolia showed an inhibitory activity of NO production in a dose-dependent manner (IC50 = 2.5 microg/ml). Additional study demonstrated that the extract of Actinodaphne lancifolia significantly suppressed the iNOS protein and gene expression in a dose-dependent manner. These results suggest that Actinodaphne lancifolia could be a potential candidate for developing an iNOS inhibitor from natural products. Further elucidation of active principles for development of new cancer chemopreventive and/or anti-inflammatory agents could be warranted.     

Suppressive effects of methoxyflavonoids isolated from Kaempferia parviflora on inducible nitric oxide synthase (iNOS) expression in RAW 264.7 cells

Ethnopharmacological relevance

The rhizomes of Kaempferia parviflora Wall. ex Baker have been traditionally used in Thailand to treat abscesses, gout, and peptic ulcers.

Aim

Previously, we reported that the chloroform fraction of a Kaempferia parviflora extract had an inhibitory effect on rat paw-edema. In the present study, we isolated the constituents of this fraction and investigated the anti-inflammatory mechanism against nitric oxide (NO) production, tumor necrosis factor-α (TNF-α) and the expression of inducible nitric oxide synthase (iNOS) as well as phosphorylated extracellular signal-regulated kinase (p-ERK), and phosphorylated c-Jun N-terminal kinase (p-JNK). In addition, effects of trimethylapigenin (4) on the enzyme activities of protein kinases possibly leading to iNOS expression were examined to clarify the targets.

Materials and methods

The chloroform fraction was isolated using silica gel column chromatography and HPLC. Isolated compounds were tested against NO and TNF-α using RAW264.7 cells. Cytotoxicity and iNOS, p-ERK and p-JNK expression were also examined.

Results

Three active components, 5,7-dimethoxyflavone (2), trimethylapigenin (4), and tetramethylluteolin (5), markedly inhibited the production of NO in lipopolysaccharide (LPS)-activated RAW264.7 cells. Compounds 2, 4, and 5 moderately inhibited production of TNF-α. Compounds 2, 4, and 5 strongly inhibited expression of iNOS mRNA and iNOS protein in a dose-dependent manner, but did not inhibit p-ERK or p-JNK protein expression. The most active compound, 4, did not inhibit the enzyme activity of inhibitor of κB kinases or mitogen-activated protein kinases, but inhibited that of spleen tyrosine kinase (SYK).

Conclusion

The mechanism responsible for the anti-inflammatory activity of methoxyflavonoids from the chloroform fraction of the rhizomes of Kaempferia parviflora is mainly the inhibition of iNOS expression, and the inhibition of SYK by 4 may be involved in the suppression of LPS-induced signaling in macrophages.     

Identification of active compounds from Caesalpinia sappan L. extracts suppressing IL-6 production in RAW 264.7 cells by PLS

Ethnopharmacological relevance

Caesalpinia sappan L. is distributed in Southeast Asia and also used as herbal medicine for the treatment of various diseases such as burning sensations, leprosy, dysentery, osteoarthritis and rheumatoid arthritis (RA). The overproduction of IL-6 plays an important role in the prognosis of RA, but the active compounds from the extracts of Caesalpinia sappan L. suppressing IL-6 production remain unknown.

Aims of the study

Identifying the main active compounds of Caesalpinia sappan L. extracts inhibiting the IL-6 production in LPS-stimulated RAW 264.7 cells by partial least squares (PLS).

Materials and methods

Sixty-four samples with different proportions of compounds were prepared from Caesalpinia sappan L. by supercritical CO₂ fluid extraction (SCFE) and refluxing. Each of 64 samples was applied to RAW 264.7 cells with LPS to evaluate whether IL-6 production by LPS is affected by addition of each sample. The IL-6 production in medium was determined by ELISA and the inhibitory activity of each sample was analyzed. In addition, the fingerprints of these 64 samples were also established by ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC–MS). We used the PLS, a simplified method, to evaluate the results from IL-6 production and fingerprints.

Results

Each of 64 samples markedly suppressed LPS-induced IL-6 production in RAW cells. The fingerprints by UPLC–MS clearly revealed variations among 64 samples produced in different extract conditions. The PLS analysis with IL-6 production and fingerprints by UPLC–MS suggested that the peaks 71, 93, 150, 157, 168 have more influence on the inhibitory activity of Caesalpinia sappan L. extracts. The peaks 71, 93, 150 are likely representing sappanone A, protosappanin E and neoprotosappanin, respectively. The peaks 157 and 168 are still at large.

Conclusion

This is the first report that sappanone A, protosappanin E, neoprotosappanin and two unidentified compounds can be considered as possible active compounds that might inhibit IL-6 production. Further studies are needed to confirm the effectiveness of these five compounds on IL-6 production and possible mechanism.     

参苏饮含药血清对小鼠巨噬细胞Toll样受体及其下游信号转导通路的影响

目的：研究参苏饮含药血清对脂多糖(LPS)和聚肌胞(POLY I∶C)刺激的小鼠巨噬细胞株RAW 264.7表达Toll样受体3(TLR3),Toll样受体4(TLR4)及其下游信号转导通路髓样分化蛋白(MyD88),肿瘤坏死因子受体相关因子-6(TRAF-6),Toll样受体相关分子(TRAM)和Toll样受体相关的干扰素活化子(TRIF) mRNA的影响。方法：用LPS(5 μg·mL^-1),POLY I∶C(50 μg·mL^-1)分别刺激RAW 264.7细胞株,同时给予参苏饮含药血清(11.2,6.7,4.0,2.4,1.5 g·kg-1·U^-1)进行干预,ELISA法测定细胞培养上清液中炎症因子肿瘤坏死因子-α(TNF-α)和干扰素-β (IFN-β)的含量。先计算参苏饮IC₅₀,然后再以IC₅₀(11,5,2.5,4.9 g·kg^-1·U^-1)做为药物剂量进行干预,荧光定量PCR方法测定TLR3,TLR4和下游通路相关指标mRNA的表达,分析评价参苏饮含药血清清热解毒药效学作用的现代药理学基础。结果：参苏饮含药血清对POLY I∶C刺激的TLR3及其下游通路的MyD88和TRAM有抑制作用,对LPS刺激的TLR4的病理性升高无抑制作用,但对TLR4下游通路TRAM和TRIF mRNA的表达有明显的抑制作用。以上综合作用引起炎症因子TNF-α和IFN-β的降低。结论：参苏饮清热解毒的药效学作用可能与抑制TLR3,MyD88,TRAM和TRIF等细胞因子的表达有关。     

仙鹤草、丹参在治疗心律失常中与一氧化氮(NO)关系的研究

目的：研究单味中药仙鹤草、丹参在治疗心律失常中与一氧化氮（NO）的关系。方法：用实验大鼠造模预测不同剂量的作用效果分别对单味仙鹤草、丹参进行实验。结果：小剂量仙鹤草、丹参均有抗心律失常的作用，大剂量丹参有降低血脂血黏度的作用。结论：血管内皮功能的逆转，是由于内皮细胞对内环境及其分泌介质的调整所致。由此，仙鹤草、丹参抗心律失常的机制可能与NO合成与释放调节有关。     

Inhibitory effects of methanol extract of Cyperus rotundus rhizomes on nitric oxide and superoxide productions by murine macrophage cell line, RAW 264.7 cells

The rhizomes of Cyperus rotundus (C. rotundus) have been used in oriental traditional medicines for the treatment of stomach and bowel disorders, and inflammatory diseases. Nitric oxide (NO) and superoxide (O2-) are important mediators in the pathogenesis of inflammatory diseases. This study was undertaken to address whether the metanol (MeOH) extract of rhizomes of C. rotundus could modulate NO and O2- productions by murine macrophage cell line, RAW 264.7 cells. The MeOH extract of rhizomes of C. rotundus showed the inhibition of NO production in a dose-dependent manner by RAW 264.7 cells stimulated with interferon-gamma plus lipopolysaccharide. The inhibition of NO production by the extract was due to the suppression of iNOS protein, as well as iNOS mRNA expression, determined by Western and Northern blotting analyses, respectively. In addition, the MeOH extract suppressed the production of O2- by phorbol ester-stimulated RAW 264.7 cells in dose- and time-dependent manners. Collectively, these results suggest that the MeOH extract of rhizomes of C. rotundus could be developed as anti-inflammatory candidate for the treatment of inflammatory diseases mediated by overproduction of NO and O2-.