Dual Effect of 3, 4-Dihydroxyacetophenone on LPS-induced Apoptosis in RAW264.7 Cells by Modulating the Production of TNF-α

To explore the pharmacological effect of 3,4-dihydroxyacetophenone (DHAP) on the apoptosis of RAW264. 7 macrophage cells and the mechanism, RAW264. 7 macrophage cells were treated with 100 or 500 mg/L lipopolysaccharide (LPS), with or without 10^-5 mol/L DHAP for 24 h. Trypan blue dye exclusion assay was used to assess cell viability. Cell apoptosis was morphological studied and flow cytometric assay was used. Tumor necrosis factor-α (TNF-α) level was measured by ELISA methods. IκB protein was determined by Western blotting. Our results showed that in 100 mg/L LPS stimulated macrophages, DHAP enhanced the cell apoptosis while in 500 mg/L LPS-stimulated macrophages, DHAP significantly inhibited the cell apoptosis. In both groups, DHAP increased the level of IκB but decreased the level of TNF-α. It is concluded that DHAP has dual effect on the apoptosis of RAW 264.7 cells treated with different concentrations of LPS. This effect may be due to the inhibition of activation of NF-κB and autocrine production of TNFα. Our study suggests that DHAP may have anti-inflammatory effect on LPS-activated macrophages.     

Dual Effect of 3, 4- Dihydroxyacetophenone on LPS-induced Apoptosis in RAW264.7 Cells by Modulating the Production of TNF-α

3, 4 dihydroxyacetophenone ( DHAP) is anactive component isolated from leaves of Tuma odongqing ( Ilex Pubescens Hook. Et Arn. Varglaber Chang), a Chinese traditional herb. It is in itially used to promote blood circulation and re move blood stasis[1, 2]. Previous experimental andclinical data proved that it could regulate the bal ance between TXA2 and PGI2, cause vesodilationand inhibit platelet aggregation[3]. It has showed agood curative effect in the…     

人结肠癌组织环加氧酶-2 mRNA剪接异构体片段分离与克隆

目的 探讨人结肠癌组织中是否存在环加氧酶-2(COX-2)选择性剪接异构体的表达及其可能意义。方法 针对人COX—2 DNA第7、8外显子序列，设计一对全新引物，并采用RT—PCR技术，从结肠癌组织中分离COX—2 mRNA，然后对电泳条带进行克隆、测序和分析。结果 正常结肠组织和结肠癌组织均发现COX—2目的条带(252bp)，但结肠癌组织则出现了一条新的电泳带(534bp)，经克隆和测序证实，该条带除目的条带的COX—2 DNA的第7、8外显子序列外，还包含第7、8外显子间的内含子序列，即保留的内含子(282bp)。根据阅读框推测，在保留的内含子第48～50碱基出现终止密码。结论 首次发现结肠癌组织中存在COX—2基因的选择性剪接异构体(Genbank accession number：BU493602，AY1512980)，其所编码蛋白可能较已报道的COX—2酶蛋白小，且蛋白质的C末端缺少阿斯匹林作用位点。     

青心酮对活化RAW264.7细胞株血红素氧合酶-1mRNA/一氧化碳及TNF-α表达的影响

目的观察青心酮对活化 RAW264.7细胞株血红素氧合酶-1mRNA/一氧化碳(Hemeoxygenase-1/carbon monoxide,HO-1mRNA/CO)及肿瘤坏死因子-α(TNF-α)表达的影响。方法用 LPS 做刺激剂,建立活化细胞模型。分别用 RT-PCR 法检测 HO-1mRNA 的表达,血红蛋白结合法检测 CO 的相对含量,Western-blot 方法检测 TNF-α蛋白质的表达。结果 10~(-5)mol/L 青心酮使活化巨噬细胞 HO-1mRNA 表达增加,CO 增加,TNF-α蛋白表达下降。结论青心酮上调活化 RAW264.7细胞株 HO-1mRNA/CO 的表达,抑制 TNF-α蛋白的产生,这可能是 DHAP 抗炎作用机制之一。     

抗炎中药的药理机制与其促炎症缓解作用的关系研究

目的：基于新的炎症消退学说，结合传统抗炎中药清热疏导的理论，将其抗炎药理学机制与促进炎症缓解过程相结合，着重观察了几种抗炎中药对几种重要炎症缓解因子及细胞凋亡的关系。方法：以离体培养的小鼠巨噬细胞株为观察对象，细菌脂多糖为刺激剂，建立炎症模型。分别采用RT-PCR检测靶基因mRNA含量，Western-blot方法检测靶基因蛋白水平，ELISA法检测细胞培养液中炎症相关细胞因子的含量，HPLC法测定PGE2的含量，血红素结合法检测CO的相对含量，流式细胞仪结合细胞形态观察判断细胞凋亡比例。