乌司他丁抑制肿瘤坏死因子-α诱导血管内皮细胞高通透性的机制研究

目的探讨乌司他丁（UTI）对肿瘤坏死因子-α（TNF-α）诱导的血管内皮细胞通透性增高的影响及其主要分子机制。 方法离体培养人脐静脉内皮细胞系EA.hy926,分别以UTI和TNF-α作用于EA.hy926,小室法测单层细胞通透性,免疫荧光法测磷酸化肌球蛋白磷酸酶靶向亚基1（p-MYPT1）的表达;分别采用免疫细胞化学法、Western Blot法测与通透性相关的关键分子（RhoA、ROCK2、MYPT1、p-MYPT1及VE-cadherin）表达的变化情况。 结果TNF-α作用下EA.hy926单层细胞通透性增加,细胞内p-MYPT1的表达量较正常对照组明显增加,而UTI可改善EA.hy926细胞的上述变化情况;免疫细胞化学结果显示,与正常对照组比较,TNF-α作用下RhoA、ROCK2的表达明显增加,而UTI可抑制RhoA、ROCK2的高表达;Western Blot结果显示,与正常对照组比较,TNF-α作用下p-MYPT1、RhoA和ROCK2的表达明显增加,VE-cadherin的表达明显降低（均P<0.05）,而UTI可抑制p-MYPT1、RhoA和ROCK2蛋白的高表达,增加VE-cadherin的表达。 结论UTI可能通过Rho/ROCK信号通路抑制TNF-α引起的EA.hy926细胞通透性增加。     

当归四逆汤含药血清对高糖培养SD大鼠背根神经元线粒体分裂及RhoA/ROCK通路的影响

目的探讨当归四逆汤含药血清对高糖培养SD大鼠背根神经元线粒体分裂及Ras同源基因家族成员A(RhoA)/Rho相关卷曲螺旋形成蛋白激酶(ROCK)通路的影响。方法各取6只SD大鼠,分别灌胃生理盐水、当归四逆汤后颈动脉取血分别制备正常血清及含药血清。取正常SD大鼠两侧背根神经元进行体外培养,随机分为对照组、高糖组、当归四逆汤组,高糖组和当归四逆汤组细胞以高糖处理,当归四逆汤组细胞再以10%的含药血清处理,对照组细胞正常培养。经正常血清、含药血清处理后,采用CCK-8实验检测各组细胞活力;采用试剂盒测定各组细胞活性氧(ROS)水平、线粒体膜电位及释放乳酸脱氢酶(LDH)、白细胞介素-6(IL-6)、白细胞介素-18(IL-18)水平;采用免疫印迹实验检测各组细胞线粒体分裂蛋白包括动力相关蛋白1(Drp1)与分裂蛋白1(Fis1)、融合蛋白即丝裂原融合蛋白1(MFN1)与丝裂原融合蛋白2(MFN2)、RhoA/ROCK通路蛋白RhoA与ROCK表达。结果与对照组比较,高糖组背根神经元ROS水平及释放的LDH、IL-6、IL-18水平,细胞中Drp1、Fis1、RhoA及ROCK蛋白表达升高,...     

乌司他丁对炎症状态下血管内皮屏障功能的影响及机制

目的阐明乌司他丁（UTI）对炎症状态下血管内皮屏障功能的影响及具体分子机制。 方法以人脐静脉内皮细胞系EA.hy926为研究对象,建立炎症细胞模型及RhoA过表达细胞模型,分别用UTI和TNF-α处理细胞,采用Transwell法、TEER法检测细胞通透性;Western Blot法及RT-PCR法检测Rho/ROCK信号通路相关关键分子（RhoA、ROCK2、MYPT1、p-MYPT1及VE-cadherin）的表达变化情况。 结果与正常对照组相比,TNF-α作用后EA.hy926细胞电阻值明显降低,细胞通透性显著升高,差异具有统计学意义[（33.67±4.04）Ω/cm² vs（67.17±3.81）Ω/cm²,t=10.435,P<0.01],细胞内RhoA、ROCK2、p-MYPT1的表达量明显增加,差异具有统计学意义（均P<0.05）,VE-cadherin的表达量明显降低,差异具有统计学意义（P<0.05）,而UTI可逆转上述变化情况;与UTI处理组相比,RhoA过表达细胞模型中RhoA、ROCK2及p-MYPT1的表达显著增高,VE-cadherin表达降低,细胞通透性增加,差异具有统计学意义（均P<0.05）,而空载病毒组中上述分子的表达水平以及细胞通透性无明显变化,差异无统计学意义（均P>0.05）。 结论UTI能通过Rho/ROCK信号通路抑制TNF-α引起的血管内皮细胞通透性增加,改善血管内皮屏障功能障碍。     

秋水仙碱体外通过RhoA/ROCK信号通路缓解心脏纤维化

目的:旨在研究秋水仙碱体外对心脏纤维化的影响。方法:使用TFGβ1建立心脏纤维化的细胞模型,2.5ng秋水仙碱或DMSO处理,通过qPCR和蛋白印迹检测成纤维细胞活化的相关指标。结果:TFGβ1促进心脏成纤维细胞活化,Collagen I、α-SMA、CTGF表达增多,秋水仙碱预处理在转录和翻译水平抑制TFGβ1诱导的Collagen I、α-SMA、CTGF升高。RhoA/ROCK信号通路是TGFβ1下游信号通路之一,秋水仙碱可抑制该信号通路。结论:秋水仙碱体外通过抑制RhoA/ROCK信号通路抑制心脏成纤维细胞活化。     

氟尿嘧啶、伊立替康和奥沙利铂诱导小鼠心肌损伤的病理生理特征及其机制

【目的】观察氟尿嘧啶（5‐FU ）、伊立替康、奥沙利铂（OXA ）诱导心肌损伤特点并分析其可能的机制。【方法】42只昆明小鼠,分为7组,每组6只,分别给予5‐Fu、伊立替康、OXA 的最大非致死量（CMAX ）和1／2CMAX给药诱导,建立小鼠心肌损伤模型,为A1、A2、B1、B2、C1、C2组,分别腹腔连续注射上述三种药物5 d,对照组（D组）注射等量生理盐水,连续注射5d。5d后,处死小鼠,取小鼠心脏组织,HE染色检测心脏组织病理学改变;提取小鼠心肌组织蛋白,检测心肌组织中丙二醛（MDA）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）水平;Western blot法检测NF‐κB和I‐κB的表达并比较。【结果】三种化疗药物均能诱导小鼠心肌损伤,心肌间质血管周围可见出血及炎性细胞大量浸润,且CMAX损伤较1／2CMAX严重。与对照组相比,化疗药物诱导的各组MDA水平显著上升,抗氧化分子 SOD和 CAT 水平显著下降,差异均有统计学意义（ P ＜0．05）;NF‐κB在三种化疗药物诱导的心肌组织中表达上升（ P ＜0．05）,I‐κB表达下降（ P ＜0．05）。【结论】5‐Fu、伊立替康、OXA均能导致心肌组织损伤,氧化应激和NF‐κB活化可能是其主要机制。     

普罗布考和氟伐他汀对由Ox—LDL诱导的人单核细胞CX3CR1表达的影响

【目的】探讨氧化低密度脂蛋白（Ox-LDL）是否上调人单核细胞（THP-1）趋化因子Fractalkine受体CX3CR1的表达,及普罗布考、氟伐他汀干预对这种诱导表达的影响。【方法】用不同浓度的Ox-LDL刺激THP-1细胞及用不同浓度普罗布考、氟伐他汀和吡咯烷二硫代氨基甲酸酯（PDTc）预处理细胞后再用OxLDL刺激,分别用半定量RT～PCR方法检测CX3CR1以及NF-κBp65的rnRNA的表达,Western—blot测定CX3CR1、NF-KBp65的蛋白表达。【结果】①与对照组比较,Ox-LDL呈浓度依赖性诱导CX3CR1及NF-κBp65在mRNA水平及蛋白水平的表达。②普罗布考、氟伐他汀可以押制Ox-LDL诱导的上述袁达;联合用药组与单药组比较抑制Ox-LDL诱导的上述表达有显著性差异。③PDTC干预后,再用Ox-LDL刺激,与未用PDTC干预组（只用Ox-LDL刺激）比较,细胞核NF-κBp65蛋白水平明显下调（P〈0．01）,但CX3CR1mR—NA和蛋白及NF-κBp65mRNA的表达均无明显下调（P〉0．05）。【结论】Ox-LDL通过NF_KB以外信号途径上调人单核细胞THP-1表达CX3CR1;PDTC可以抑制NF—κB的活化,但是不能抑制Ox-LDL上调人单核细胞THP-1表达CX3CR1;普罗布考和氟伐他汀可以抑制NF-κB的活化,亦能抑制氧化低密度脂蛋白上调人单核细胞THP-1表达CX3CR1,这种抑制作用与普罗布考和氟伐他汀抑制NF-κB的活化无关。     

蛋白激酶C对血管内皮功能的影响

【目的】研究血管内皮蛋白激酶C对内皮通透性及粘附功能的影响。【方法】以血管内皮细胞为研究对象,以流式分析法测定细胞间黏附分子-1（ICAM-1）,血管细胞黏附分子-1（VCAM-1）的表达;以同位素标记法测定HUVECs的粘附率;双室培养法测定HUVECs的通透率。【结果】10ng／mlPMA处理HUVECs后,HUVECs的通透性于30min时开始明显增高;VCAM-1,ICAM-1表达增强,对血小板粘附率2h达到最大值。【结论】PKC活化能其上调血管内皮细胞VCAM-1、ICAM-1的表达,并增强其粘附性。HUVECs的PKC活化与血管内皮细胞通透性增加有关。     

辛伐他汀对脂多糖诱导人THP-1单核细胞表达MMP-9的影响

【目的】研究辛伐他汀对脂多糖（LPS）诱导人THP-1单核细胞表达基质金属蛋白酶9（MMP-9）的影响,探讨辛伐他汀稳定动脉粥样硬化（AS）斑块的机制。【方法】体外培养人THP-1单核细胞,分为对照组、LPS组、辛伐他汀低、中、高浓度组;辛伐他汀三组加入不同浓度辛伐他汀预孵2h与LPS组均加入LPS刺激24h,应用Western blotting与ELISA分别检测各组细胞蛋白与培养基上清中MMP-9水平。【结果】LPS诱导人THP-1单核细胞MMP-9表达显著增加,辛伐他汀呈浓度依赖性显著抑制LPS诱导人THP-1单核细胞MMP-9表达。【结论】辛伐他汀通过抑制LPS诱导人THP-1单核细胞MMP-9表达,可能是其在炎症状态下稳定AS斑块的机制之一。     

天麻素干预对过氧化氢诱导的PC12细胞凋亡、活力及PI3K／AKT信号通路蛋白的影响

【目的】探讨磷脂酰肌醇3激酶（PI3K）蛋白表达量及蛋白激酶 B（AKT ）信号通路在过氧化氢（H2 O2）诱导的 PC12细胞中的作用及天麻素的干预对其通路的影响。【方法】PC12细胞随机分为正常对照组,模型组（400μmol／L H2 O2）,天麻素低、中、高浓度组（0．1、1、10μmol／L 天麻素＋400μmol／L H2 O2）。咪唑蓝法检测各组细胞活力,Hoechst 染色观察各组细胞凋亡情况,比色法检测天冬氨酸蛋白水解酶（Caspase 3）、Caspase 8及 Caspase 9活性,western blot 分析 Bcl‐2、Bax 及 PI3K 蛋白表达量与 AKT 磷酸化水平。【结果】与正常对照组比较,模型组中细胞活力下降,细胞凋亡率提高,Caspase 3、Caspase 8及 Caspase 9活性提高,Bcl‐2及 PI3K 表达量下降,Bax 表达量上升,AKT 磷酸化水平降低,差异均具有统计学意义（ P ＜0．01）;与模型组比较,天麻素低、中、高浓度组细胞活力提高,细胞凋亡率降低,Caspase 3、Caspase 8及 Caspase 9活性降低,Bcl‐2、PI3K 蛋白表达量及 AKT 磷酸化水平提高,天麻素中、高浓度组 Bax 表达量降低,差异均具有统计学意义（ P ＜0．01）。【结论】天麻素可通过激活 PI3K／AKT 信号通路,从而抑制 H2 O2诱导的 PC12细胞凋亡。     

法舒地尔和RhoA沉默对神经干细胞增殖的影响

背景：Rho及其相关分子在神经轴突生长、分化、延伸及突触形成中起重要作用,阻断和抑制RhoA/ROCK通路可促进神经干细胞的增殖与生长。目的：观察Rho激酶抑制剂法舒地尔和RNAi介导的RhoA基因沉默对大鼠神经干细胞增殖的影响。方法：体外培养Wistar胎鼠神经干细胞,分6组干预：空白对照组,5,10,15,20μmol/L法舒地尔组,siRNA沉默RhoA基因组。干预后第3天,采用RT-PCR,Westernblot检测各组神经干细胞RhoA基因及蛋白的表达。应用MTT比色法观察神经干细胞增殖情况;采用流式细胞术测定神经干细胞周期分布的变化。结果与结论：15,20μmol/L法舒地尔组、siRNA沉默RhoA基因组神经干细胞RhoA基因及蛋白表达量较5,10μmol/L法舒地尔组、空白对照组明显降低（P〈0.05）,细胞的生长速度较5,10μmol/L法舒地尔组、空白对照组明显增快（P〈0.05）,细胞周期G0/G1期减少（P〈0.05）,S期细胞数增多（P〈0.05）。当法舒地尔浓度增加到20μmol/L时对细胞的作用并非随浓度的增加而增强,与15μmol/L组的差异无显著性意义（P〉0.05）。15,20μmol/L法舒地尔组与siRNA沉默RhoA基因组相比差异无显著性意义（P〉0.05）。说明Rho激酶抑制剂法舒地尔和RNAi介导的RhoA基因沉默在体外均能促进神经干细胞增殖,法舒地尔最佳作用浓度为15μmol/L。     

Ginseng (Panax quinquefolius) attenuates leptin-induced cardiac hypertrophy through inhibition of p115Rho guanine nucleotide exchange factor-RhoA/Rho-associated, coiled-coil containing protein kinase-dependent mitogen-activated protein kinase pathway activation

Leptin is a 16-kDa peptide primarily derived from white adipocytes and is typically elevated in plasma of obese individuals. Although leptin plays a critical role in appetite regulation, leptin receptors have been identified in numerous tissues including the heart and have been shown to directly mediate cardiac hypertrophy through RhoA/ROCK (Ras homolog gene family, member A/Rho-associated, coiled-coil containing protein kinase)-dependent p38 mitogen-activated protein kinase (MAPK) activation; however, the basis for RhoA stimulation is unknown. Rho guanine nucleotide exchange factors (GEFs) catalyze the exchange of GDP for GTP resulting in Rho activation and may be the potential upstream factors mediating leptin-induced RhoA activation and therefore a potential target for inhibition. We investigated the effects of North American ginseng (Panax quinquefolius), reported to reduce cardiac hypertrophy, on RhoA/ROCK and MAPK activation in ventricular cardiomyocytes exposed to leptin (50 ng/ml) and the possible role of p115RhoGEF and p63RhoGEF in these responses. Leptin produced a robust hypertrophic response that was associated with RhoA/ROCK activation resulting in a significant increase in cofilin-2 phosphorylation and actin polymerization, the latter evidenced by a reduction in the G/F actin ratio. These effects were prevented by ginseng (10 μg/ml). The stimulation of RhoA/ROCK by leptin was associated with significantly increased p115RhoGEF gene and protein expression and exchange activity, all of which were completely prevented by ginseng. The ability of ginseng to prevent leptin-induced activation of RhoA/ROCK was further associated with diminished p38 MAPK activation and nuclear translocation. These results demonstrate a potent inhibitory effect of ginseng against leptin-induced cardiac hypertrophy, an effect associated with prevention of p115RhoGEF-RhoA/ROCK-dependent p38 MAPK activation.     

Protein kinase A inhibits lysophosphatidic acid-induced migration of airway smooth muscle cells

Lysophosphatidic acid (LPA) is a bioactive phospholipid that is released from activated platelets and affects contractile properties of airway smooth muscle cells. However, possible roles of LPA on cell migration, one of the initial events of airway remodeling, are not clarified. This study aimed to examine the effects of LPA on migration and actin fiber formation in bovine tracheal smooth muscle cells (BTSMCs). Random and oriented cell migrations were examined with wound assay and Boyden chamber assay, respectively. Cytosolic actin fibers were stained with rhodamine-phalloidin. Membrane translocation of RhoA, a hallmark of RhoA activation, was assessed by Western blotting. LPA augmented the migration of BTSMCs from wounded confluent monolayer but did not accelerate the chemotactic migration toward LPA. LPA also induced a transient actin reorganization and RhoA activation. Dense actin fibers were observed mainly in the wound edge but not in migrated cells, thereby suggesting the role of actin reorganization in the initiation of cell migration. LPA-induced actin fiber formation was blocked by Y27632 [R-(+)-trans-N-(4-pyridyl)-4-(1-aminoethyl)-cyclohexane carboxamide], an inhibitor of Rho kinase. Effects of LPA on migration and actin fiber formation were also inhibited by cAMP-elevating agents, i.e., dibutyryl cAMP, forskolin, isoproterenol, and theophylline. KT5720 (9S,10S,12R)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid hexyl ester], a protein kinase A (PKA) inhibitor, reversed the inhibitory actins of cAMP on LPA-induced responses. These results indicate that LPA induces cAMP/PKA-sensitive, RhoA-mediated random migration of BTSMCs. Regulation of this mechanism would be beneficial for the control of airway remodeling.     

Fasudil-induced hypoxia-inducible factor-1alpha degradation disrupts a hypoxia-driven vascular endothelial growth factor autocrine mechanism in endothelial cells

Hypoxic response of endothelial cells (EC) is an important component of tumor angiogenesis. Especially, hypoxia-inducible factor-1 (HIF-1)-dependent EC-specific mechanism is an essential component of tumor angiogenesis. Recently, the Rho/Rho-associated kinase (ROCK) signaling has been shown to play a key role in HIF-1alpha induction in renal cell carcinoma and trophoblast. The present study was designed to investigate whether low oxygen conditions might modulate HIF-1alpha expression through the Rho/ROCK signaling in human umbilical vascular ECs (HUVEC). Pull-down assay showed that hypoxia stimulated RhoA activity. Under hypoxic conditions, HUVECs transfected with small interfering RNA of RhoA and ROCK2 exhibited decreased levels of HIF-1alpha protein compared with nontargeted small interfering RNA transfectants, whereas HIF-1alpha mRNA levels were not altered. One of ROCK inhibitors, fasudil, inhibited hypoxia-induced HIF-1alpha expression without altering HIF-1alpha mRNA expression. Furthermore, proteasome inhibitor prevented the effect of fasudil on HIF-1alpha expression, and polyubiquitination was enhanced by fasudil. These results suggested that hypoxia-induced HIF-1alpha expression is through preventing HIF-1alpha degradation by activating the Rho/ROCK signaling in ECs. Furthermore, hypoxia induced both vascular endothelial growth factor (VEGF) and VEGF receptor-2 expression through the Rho/ROCK/HIF-1alpha signaling in HUVECs. Thus, augmented VEGF/VEGF receptor-2 autocrine mechanism stimulated HUVEC migration under hypoxic conditions. In summary, the Rho/ROCK/HIF-1alpha signaling is an essential mechanism for hypoxia-driven, VEGF-mediated autocrine loop in ECs. Therefore, fasudil might have the antimigratory effect against ECs in tumor angiogenesis.     

Smoothened表达对类风湿关节炎成纤维样滑膜细胞RhoA/ROCK通路的影响

目的初步探讨Sonic Hedgehog(Shh)信号通路分子Smoothened(Smo)对类风湿关节炎(RA)成纤维滑膜细胞(FLS)RhoA/ROCK通路相关分子的影响。方法收集病情活动(DAS28≥3.2)RA患者关节镜手术或关节置换术切除的滑膜组织,组织块培养法培养RA-FLS作为细胞模型,流式细胞术检测CD55阳性率鉴定细胞,然后分别予Smo分子激动剂Purmorphamine或抑制剂KAAD-Cyclopamine处理,应用GST-pull down法检测RhoA活性,Western blot检测ROCK活性与Smo蛋白表达。结果与对照组相比,RA-FLS经Purmorphamine刺激后,活性RhoA蛋白、磷酸化MYPT1蛋白及Smo蛋白均上调(P<0.05);经KAAD-Cyclopamine处理后,活性RhoA蛋白、磷酸化MYPT1蛋白及Smo蛋白均下调(P<0.05)。结论 RA-FLS Smo表达可影响RhoA/ROCK信号的传导。Smo可能参与了RA-FLS中Shh信号通路非经典途径的调控。     

RhoA prenylation inhibitor produces relaxation of tonic smooth muscle of internal anal sphincter

RhoA prenylation is a critical step for the translocation of RhoA to the membrane and its activation in response to agonist-induced sustained contraction of the smooth muscle. However, the effect and role of RhoA prenylation in the spontaneously tonic smooth muscle, such as internal anal sphincter (IAS), is not known. Present studies determined RhoA prenylation and its association with the basal tone in the IAS before and after the RhoA prenylation inhibitor, geranylgeranyl transferase inhibitor GGTI-297 [N-4-[2(R)-amino-3-mercaptopropyl]amino-2-naphthylbenzoyl-(L)-leucine,TFA]. Western blot analyses of cytosolic and membrane fractions determined the effects of RhoA prenylation inhibition on the cellular distribution of the RhoA. Additional studies were performed to determine the relationship between RhoA prenylation and Rho kinase (ROCK) activity. GGTI-297 decreased prenylation of RhoA, decreased ROCK activity, and caused a corresponding fall in the IAS tone. These inhibitory effects following RhoA prenylation blockade were demonstrated to be directly on the spontaneously contracted IAS smooth muscle cells. Western blot analysis revealed high levels of RhoA in the IAS smooth muscle cellular membrane in the basal state, and GGTI-297 shifted the RhoA localization to the cytosol. RhoA prenylation may play an important role in the translocation of RhoA to the smooth muscle cell membrane leading to its activation and for the maintenance of basal tone in the IAS.     

Actin cytoskeleton dynamics promotes leptin-induced vascular smooth muscle hypertrophy via RhoA/ROCK- and phosphatidylinositol 3-kinase/protein kinase B-dependent pathways

Obesity is associated with increased leptin production that may contribute to cardiovascular pathology through a multiplicity of effects. Leptin has been shown to contribute to vascular remodeling through various mechanisms, including production of vascular smooth muscle (VSMC) hypertrophy; however, the mechanisms underlying the vascular hypertrophic effect of leptin remain unknown. In the present study, we investigated the contributions of the RhoA/Rho kinase (ROCK) and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways, actin dynamics, and the expression of serum-response factor (SRF) in the hypertrophic effects of leptin on vascular tissue. Strips of rat portal vein (RPV) were cultured with or without leptin at 3.1 nM for 1 to 3 days. Leptin significantly increased RhoA activity by 163 +/- 20%, whereas phosphorylation of downstream factors, including LIM kinase 1 and cofilin-2, was increased by 160 +/- 25 and 290 +/- 25%, respectively. Leptin also significantly phosphorylated Akt by 130 +/- 30%, which was inhibited by the PI3K inhibitor 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002). RhoA/ROCK and PI3K/Akt activation was associated with a significant increase in RPV wet weight (11 +/- 1%), protein synthesis (45 +/- 7%), SRF expression (136 +/- 11%), and polymerization of actin, as reflected by an increase in the F-/G-actin ratio, effects that were significantly attenuated by a leptin receptor (leptin obese receptor) antibody, the ROCK inhibitor (+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl) (Y-27632) as well as the PI3K inhibitor LY294002. Our results indicate that the activation of RhoA/ROCK and PI3K/Akt plays a pivotal role in leptin signaling, leading to the development of VSMC hypertrophy through a mechanism involving altered actin dynamics.     

大蒜素对LM-8细胞Bcl-2及Bax表达的影响

背景:有研究证实,大蒜素对LM-8细胞增殖及凋亡有影响.目的:观察大蒜素干预C3H小鼠骨肉瘤细胞株LM-8细胞Bcl-2、Bax凋亡蛋白的表达,以及LM-8细胞的形态学变化与Bcl-2及Bax变化的关系.设计:随机分组,非盲法,细胞水平体外实验.单位:实验于2006-09/2007-05在华中科技大学同济医学院附属协和医院中心实验室完成.材料:实验所用C3H小鼠LM-8骨肉瘤细胞株购自解放军第四军医大学实验动物中心.大蒜素为武汉汇海公司产品,是从大蒜球茎中分离出的硫化物.Cell Counting Kit-8试剂购于上海同仁化学研究所,Bcl-2和Bax抗体及SP试剂盒购于福州迈新生物技术开发公司.方法:以含体积分数为0.1新生牛血清的1640完全培养基,培养LM-8细胞,制作细胞爬片.SP免疫细胞组织化学技术检测细胞爬片中Bcl-2和Bax蛋白表达;倒置显微镜下观察5.0,10.0和15.0 mg/L质量浓度大蒜素作用前后LM-8细胞形态变化;将LM-8细胞调整至7.5×107L-1接种于96孔板,用1.0,5.0,10.0和15.0 mg/L质量浓度的大蒜素处理细胞,设立不加任何处理因素的对照组及不含细胞和药物的培养基空白组,孵育24,48,72 h后取出培养板,加入CCK-8测定吸光度值,计算LM-8细胞生长抑制率:以5.0,10.0和15.0 mg/L质量浓度大蒜素干预LM-8细胞24,48,72 h,消化离心收集细胞,以流式细胞仪分析细胞凋亡率的变化.主要观察指标:LM-8细胞中Bcl-2和Bax蛋白表达;LM-8细胞形态及增殖、凋亡情况.结果:①Bcl-2和Bax蛋白表达:大蒜素可以降低Bcl-2表达,增强Bax表达,经15.0mg/L大蒜素作用72h,Bcl-2和Bax蛋白表达阳性率及Bcl-2/Bax表达与对照组比较,差异有显著性意义(P＜0.01).②LM-8细胞的形态:经不同质量浓度大蒜素干预后均出现明显凋亡表现.③LM-8细胞的增殖:大蒜素能明显抑制LM-8细胞的增殖,当大蒜素浓度从1.0 mg/L增加到15.0 mg/L,LM-8细胞72 h时生长抑制率由(23.87±3.26)%增至(58.32±5.38)%,在72 h其药物半数抑制率浓度是11.09 mg/L.④LM-8细胞的凋亡:5.0,10.0和15.0 mg/L质量浓度的大蒜素作用72 h后可诱导LM-8细胞凋亡,且呈浓度依赖性(P＜0.05).结论:①大蒜素可抑制LM-8细胞增殖,该效应与大蒜素的浓度和时间有关.②大蒜素可诱导LM-8细胞凋亡,作用呈浓度依赖性.③大蒜素抑制LM-8细胞增殖和诱导LM-8细胞凋亡的机制可能与下调Bcl-2的表达和上调Bax的表达有关.