细胞因子促进人BT325胶质瘤细胞产生一氧化氮

目的:观察脂多糖及一些前炎性细胞因子对体外培养的星形胶质细胞产生一氧化氮(NO)的影响。方法:Griess法检测细胞培养上清中NO_2-含量。结果:体外培养4h时人BT325星形胶质瘤细胞开始产生NO,12h达高峰(15.0-17.5μmol·L~(-1))并持续至72h.LPS 1mg·L~(-1),IFN-γ100kU·L~(-1),TNF-α100kU·L~(-1),IL-1 100kU·L~(-1)及IL-2100kU·L~(-1)可增强体外培养的BT325细胞产生NO,以TNF-α,IL-1和IL-2作用较为明显,四种细胞因子合用则作用更强。结论:炎症刺激或前炎性细胞因子促进神经胶质细胞产生NO。     

海洛因成瘾者血清中细胞因子含量变化与免疫功能调查

目的：探讨海洛因成瘾者血清中细胞因子含量的变化及其与免疫功能损害的相互关系。方法：用放射免疫法测定４５例海洛因成瘾者和４０例正常人血清中白细胞介素－１（ＩＬ－１）、白细胞介素－２（ＩＬ－２）和肿瘤坏死在子（ＴＮＦ）的含量。结果：海洛因成瘾者血清中３种细胞因子含量显著低于正常组（Ｐ〈０．０１）。结论：海洛因成瘾者细胞因子含量降低很可能是造成成瘾者免疫功能（特异性免疫和非特异性免疫）损害的主要原因。     

晚期糖基化终产物诱导星型胶质细胞活化：细胞因子分泌与一氧化氮释放

目的:研究两种体外温育的晚期糖基化终产物(AGE)是否可以诱导星型胶质细胞分泌白介素-1β和肿瘤坏死因子α,并导致氧应激增加、一氧化氮释放.方法:RT-PCR技术检测两种细胞因子水平及AGE受体(RAGE)存在与否;DTNB反应测量还原型谷胱甘肽的水平;利用Griess试剂测量一氧化氮含量.结果:AGE 1 g/L(尤其是半乳精温育产物)作用72小时后使星型胶质细胞培养上清和细胞裂解物的细胞因子含量显著升高.且呈剂量依赖性.半定量RT-PCR证明两种细胞因子的变化是由于其转录水平增加所致.AGE还可导致星型胶质细胞内还原性谷胱甘肽减少,一氧化氮释放.RAGE存在于此类星型胶质细胞中.结论:AGE可诱导星型胶质细胞分泌炎性因于白介素-1β和肿瘤坏死因子α,并升高氧应激水平,这至少部分解释了AGE在神经变性性疾病如阿尔采默病和帕金森氏病以及脑衰老中的负性作用.     

人IL—1,IL—6及TNFα基因在卵巢癌患者单个核细胞中的表达与相互关系

利用ＭＴＴ法及原位杂交技术，检测了４６例卵巢癌患者外周血单个核细胞（ＰＢＭＣ）及腹水细胞分泌的ＩＬ－１、ＩＬ－６和ＴＮＦα蛋白水平及其ｍＲＮＡ的表达。结果表明，卵巢癌患者血ＰＢＭＣ细胞、腹水细胞的ＩＬ－１、ＩＬ－６和ＴＮＦα分泌水平明显高于健康对照组，具有统计学意义。且加入一定剂量的ＩＬ－１能促进这些细胞的ＩＬ－６及ＴＮＦα分泌水平，这种作用能被ＩＬ－１的单克隆抗体封闭。提示：ＩＬ－１、ＩＬ－６和     

脂多糖刺激体外大鼠小胶质细胞产生细胞肽和一氧化氮

AIM: To study the characterization of interleukin (IL)-1, IL-2, tumor necrosis factor-alpha (TNF-alpha), and nitric oxide (NO) production in microglia stimulated with lipopolysaccharides (LPS). METHODS: Primary cultured neonatal rat microglia were incubated with LPS (0-10 mg.L-1) for 0-72 h. The supernatants and lysates were collected. IL-1, IL-2, and TNF-alpha were assayed by mouse thymocyte proliferation, mouse spleen cell proliferation, and 1929 cytotoxity, respectively. NO was assayed by Griess reaction. RESULTS: Extracellular IL-1, TNF-alpha, and NO production reached peak levels at LPS 1 mg.L-1. Intracellular IL-1 production reached its peak level at LPS 100 micrograms.L-1. Intracellular TNF-alpha level was very low. IL-1, TNF-alpha, and NO activities were detected at 1, 4, and 8 h, after the cells were stimulated with LPS. IL-1 got to its peak value at 8 h, TNF-alpha, and NO reached the highest levels at 24 h. However, IL-2 activity was not detected after the microglia were stimulated with LPS 0-10 mg.L-1 during the incubation period. CONCLUSION: Rat microglia stimulated with LPS in vitro produced proinflammatory cytokines and NO.     

金钗石斛生物总碱对脂多糖激活星形胶质细胞产生炎症因子的影响

目的观察金钗石斛生物总碱对外源性内毒素脂多糖(lipopolysaccharide,LPS)激活大鼠大脑皮层星形胶质细胞(astrocyte)及诱导其产生和释放炎症介质的影响,探讨石斛生物总碱对星形胶质细胞的抗炎作用。方法通过MTS检测细胞存活率,ELISA法检测TNF-α炎性因子蛋白的表达,实时定量多聚酶链反应(real time RT-PCR)检测炎症相关基因TNF-α、IL-6 mRNA的表达。结果①LPS刺激星形胶质细胞后,MTS检测吸光度明显升高,与正常组比较差异有显著性;②金钗石斛生物总碱能够降低LPS所致的TNF-α蛋白的高表达(P<0.05);③金钗石斛生物总碱能够降低LPS诱导的星形胶质细胞吸光度的升高,同时明显抑制LPS所致的TNF-α、IL-6 mRNA的高表达。结论金钗石斛生物总碱能够拮抗LPS所引起的炎症反应,其作用与抑制星形胶质细胞的激活及其炎症因子的释放密切相关。     

脑缺血后活化星形胶质细胞所致损伤因子的探讨

脑缺血损伤时,活化星形胶质细胞产生一系列细胞因子,其中一氧化氮、内皮素、磷脂酶A2、肿瘤坏死因子等通过各种机制对缺血后神经细胞产生毒性作用,引起神经细胞坏死、凋亡。深入了解活化星形胶质细胞对缺血性神经细胞损伤的作用机制,对脑缺血的治疗具有重要意义。     

脂多糖通过MAPK通路影响星形胶质细胞的谷胱苷肽和肿瘤坏死因子生成

目的 研究脂多糖(LPS)对原代培养的星形胶质细胞(AC)代谢的影响及其可能机制.方法 原代培养AC,予以LPS作用30min、24、48和72h后,观察AC的生存率、肿瘤坏死因子α(TNF-α)、谷胱苷肽(GSH)和谷胱苷肽过氧化物酶(GPx)含量的变化,Western blot检测AC磷酸化MAPK家族信号蛋白P-p38的表达,观察MAPK通路抑制剂对TNF-α分泌的影响.结果 低剂量LPS促进AC增殖,高剂量抑制.LPS(10μg/ml)作用72h后细胞内GPx活性降低,GSH含量下降.TNF-α的含量随LPS作用时间延长而升高,48h后与对照组相比有显著性差异,P-p38蛋白高峰出现在24h,随后下降.MAPK通路抑制剂可阻断TNF-α的升高.结论 LPS激活的AC下调GSH的表达,增加TNF-α的分泌,其可能的分子机制是激活MAPK通路.     

银杏内酯A和B及石杉碱甲抑制大鼠C6及人BT325胶质瘤细胞产生一氧 …

AIM: To study the effects of ginkgolide A, B (Gin A, Gin B) and huperzine A (Hup A) on nitric oxide (NO) production from cultured astrocytes. METHODS: Nitrites in supernatants were measured with Griess assay. RESULTS: Hup A 0.001-100 mumol.L-1 time- and concentration-dependently inhibited the NO production from rat C6 astrocytoma cells. The NO production from C6 cells was concentration-dependently inhibited by the treatment with Gin A or Gin B 0.001-10 micromol.L-1 for 24 h. The NO production from human BT325 astrocytoma cells was concentration-dependently inhibited by Hup A, Gin A, or Gin B 0.01-10 micromol.L-1 for 24 h. CONCLUSION: Gin A, Gin B, and Hup A inhibited astrocytes producing NO.     

银杏内酯A和B及石杉碱甲抑制大鼠C6及人BT325胶质瘤细胞产生一氧化氮(英文)

目的:观察银杏内酯A(Gin A),银杏内酯B(GinB)及石杉碱甲(Hup A)对体外培养的星形细胞产生一氧化氮(NO)的影响。方法:Griess法检测细胞培养上清中NO_2~-含量。结果:HupA0.001-100μmol·L~(-1)明显抑制大鼠C6细胞产生NO,该抑制作用呈浓度及时间依赖性,在0.001-10μmol·L~(-1)范围作用24h,Gin A和Gin B均浓度依赖性地抑制C6细胞产生NO。在0.01-10μmol·L~(-1)范围作用24h,Hup A,Gin A和Gin B均浓度依赖性地抑制人BT325细胞产生NO。结论:Hup A,GinA和Gin B抑制大鼠及人星形细胞产生NO。     

Transmural pressure inhibits nitric oxide release from human endothelial cells.

We examined the effect of transmural pressure on histamine-stimulated nitric oxide release from cultured endothelial cells prepared from human umbilical cord veins. PO2 and pH were kept constant throughout the experiments. Various levels of transmural pressure and atmospheric pressure (40, 80, 120 and 160 mm Hg) were applied. Nitric oxide release was inhibited in a pressure-dependent manner. The inhibitory effects were reversible, and nitric oxide had no effect on the morphology of the cells. Our results suggest that transmural pressure-mediated inhibition of nitric oxide release contributes to pressure-induced vasoconstriction and reduced endothelium-dependent relaxation in patients with hypertension.     

Curcuminoid analogs inhibit nitric oxide production from LPS-activated microglial cells

The chemically modified analogs, the demethylated analogs 4–6, the tetrahydro analogs 7–9 and the hexahydro analogs 10–12, of curcumin (1), demethoxycurcumin (2) and bisdemethoxycurcumin (3) were evaluated for their inhibitory activity on lipopolysaccharide activated nitric oxide (NO) production in HAPI microglial cells. Di-O-demethylcurcumin (5) and O-demethyldemethoxycurcumin (6) are the two most potent compounds that inhibited NO production. The analogs 5 and 6 were twofold and almost twofold more active than the parent curcuminoids 1 and 2, respectively. Moreover, the mRNA expression level of inducible NO synthase was inhibited by these two compounds. The strong neuroprotective activity of analogs 5 and 6 provide potential alternative compounds to be developed as therapeutics for neurological disorders associated with activated microglia.     

Ethanol can inhibit nitric oxide production.

Endogenous nitric oxide (NO) in exhaled air from anaesthetized rabbits was monitored by chemiluminescence. Ethanol (3-30 mmol kg-1) infused i.v. dose dependently reduced the levels of exhaled NO, with an IC50 of 23 +/- 3 mmol kg-1. L-Arginine (1 g kg-1) did not reverse the effect of ethanol. These results demonstrate the inhibition of NO formation by ethanol in vivo.     

Sesquiterpenoids from Inula racemosa Hook. f. inhibit nitric oxide production

A novel trinorsesquiterpene (1), three new (2-4), and 10 known sesquiterpenes were isolated from the roots of Inula racemosa Hook. f. The structures and absolute configurations of the new sesquiterpenes were elucidated by extensive spectroscopic and computational methods. All compounds were evaluated for their inhibition of LPS-induced nitric oxide production in RAW264.7 macrophages, and the results indicated that compounds 9, 12, and 13 moderately inhibited nitric oxide production with IC?? values of 7.39?±?0.36, 6.35?±?0.26, and 5.39?±?0.18?μM, respectively.     

Novel peptides enhance the production of nitric oxide and inducible nitric oxide synthase (iNOS) gene expression in murine macrophage

Bioactive novel polypeptide of anuran skin has a wide range of antimicrobial properties against the infection and tumour cell. Macrophages are known to produce the Nitric oxide (NO) by a variety of cells upon activation. NO produced by the activated macrophages an important mediator for antimicrobial and tumoricidal activity. In-vitro macrophage exposed with medium alone, containing LPS, containing polypepeptides and LPS plus polypeptides for 24 h showed enhanced production of NO with respect to control and LPS treated and significant increase in NO production in LPS plus polypeptide. Western blot and PCR analysis also showed that increased production of protein expression and mRNA expression of inducible nitric oxide synthase (iNOS). These findings suggest that novel polypeptides are potent activating agent for enhanced production of NO through activation of iNOS gene.     

Inhibitors of nitric oxide production from Stemona javanica

In our screening program for bioactive natural products from our library of tropical plants, the extract prepared from the roots of Stemona javanica inhibited NO production in mouse macrophage-like cell line J774.1 stimulated by lipopolysaccharide (LPS). Bioassay-guided fractionation of the extract from S. javanica led to the isolation of two active compounds, stemofoline (1) and stemanthrene C (2). The inhibition mechanism of 1 was proposed to suppress iNOS expression in J774.1 cells stimulated by LPS, whereas that of 2 was due to potent radical scavenging activity resulting in NO inhibitory activity.     

Thrombin-promoted release of UDP-glucose from human astrocytoma cells

As an increasing number of non-cardiac drugs have been reported to cause QT interval prolongation and torsades de pointes (TdP), we extensively studied the utility of atrioventricular (AV) block animals as a model to predict their torsadogenic action in human. The present review highlights such in vivo proarrhythmia models. In the case of the canine model, test substances were administered p.o. at conscious state >4 weeks after the induction of AV block, with subsequent Holter ECG monitoring to evaluate drug effects. Control AV block dogs (no pharmacological treatment) survive for several years without TdP attack. For pharmacologically treated dogs, drugs were identified as high, low or no risk. High-risk drugs induced TdP at 1-3 times the therapeutic dose. Low-risk drugs did not induce TdP at this dose range, but induced it at higher doses. No-risk drugs never induced TdP at any dose tested. Electrophysiological, anatomical histological and biochemical adaptations against persistent bradycardia-induced chronic heart failure were observed in AV block dogs. Recently, we have developed another highly sensitive proarrhythmia model using a chronic AV block cynomolgus monkey, which possesses essentially the same pathophysiological adaptations and drug responses as those demonstrated in the canine model. As a common remodelling process leading to a diminished repolarization reserve may present in patients who experience drug-induced TdP and in the AV block animals, the in vivo proarrhythmia models described in this review may be useful for predicting the risk of pharmacologically induced TdP in humans.