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1.
《菌物学报》2017,(9):1278-1288
本文对硬毛粗盖孔菌子实体不同提取物的抗肿瘤活性进行筛选。通过建立H_(22)荷瘤小鼠肿瘤移植模型,研究硬毛粗盖孔菌子实体的石油醚提取物、二氯甲烷提取物、乙酸乙酯提取物、甲醇提取物以及水提取物等5种提取物的高、中、低剂量组对H_(22)荷瘤小鼠的抑瘤作用,并对其H_(22)荷瘤小鼠的抑瘤率、体质量、胸腺指数、脾脏指数、肝脏指数、肾脏指数进行了考察。对小鼠肿瘤、脾脏、肾脏进行了组织病理学检查,对血清中的细胞因子IL‐2、IL‐4、IFN‐γ及TNF‐α的含量进行测定。结果表明:各组分均有抑瘤效果,其中乙酸乙酯提取物中剂量组(1 000mg/kg)抑瘤效果最佳,与阴性对照组比较有极显著差异(P0.01),并且这组的H_(22)荷瘤小鼠血清中白介素‐2的含量显著增加,同时肿瘤细胞通过HE染色后,可观察到出现坏死面积增大,与抑制肿瘤活性具有相关性。  相似文献   

2.
目的:观察凹项藻提取物(Laurenciaterpenoid extract,LET)对接种H22细胞小鼠的肿瘤生长及血管内皮细胞生长因子(VEGF)、增殖细胞核抗原(PCNA)表达的影响.方法:昆明小鼠随机分为5组(10只,组),即模型组、LET低中高剂量组(25、50、100 mg/kg·d-1)、环磷酰胺组(CTX对照组).各组小鼠左前腋下皮下接种H22肝癌细胞,第二天除模型组外,其余4组分别以不同剂量的LET、CTX灌胃,于15天后处死,完整剥离出肿瘤,称重,计算抑瘤率.免疫组化法测定肿瘤组织中VEGF、PCNA的表达.结果:LET低、中、高剂量组小鼠H22肿瘤质量增长均较模型组缓慢(P<0.05),抑瘤率分别为27.5%、34.9%、41.4%;同时LET中、高剂量组VEGF阳性表达较模型组显著减少(P<0.05),低剂量组未见明显变化,但LET各剂量组PCNA阳性表达较模型组显著减少(P<0.05).结论:LET各剂量组可以抑制小鼠H22肿瘤的生长,具有较高的抑瘤活性,且中、高剂量组能抑制VEGF的表达(P<0.05),低、中、高剂量组能抑制PCNA的表达(P<0.05).LET对肿瘤组织VEGF、PCNA表达的抑制作用可能是其抗H22肿瘤及抗血管生成的一个重要原因.  相似文献   

3.
李旭阳  包海鹰 《菌物研究》2013,11(3):202-206
研究了木蹄层孔菌子实体的石油醚提取物、氯仿提取物、甲醇提取物对体内抑制肿瘤活性及对免疫功能的影响。建立H22荷瘤小鼠模型,观察木蹄层孔菌不同提取物对荷瘤小鼠的抑瘤效果,通过抑瘤率、免疫器官指数及生存时间的影响来评价不同提取物的活性。结果表明:木蹄层孔菌子实体的石油醚提取物、氯仿提取物、甲醇提取物均有一定的抑制肿瘤作用,其中石油醚提取物下层沉淀的抑制作用最显著,当质量分数为100 mg/kg时抑瘤率高达56.29%,接近阳性药的抑瘤率58.78%,可使小鼠的体质量、脾指数和胸腺指数增加,延长H22荷瘤小鼠的生存时间。木蹄层孔菌石油醚提取物下层沉淀在一定的剂量范围内,能较好地抑制小鼠肿瘤的生长,提高机体的免疫功能。  相似文献   

4.
徐清燕  梁惠  秦松 《生物磁学》2009,(24):4656-4659
目的:观察重组别藻蓝蛋白(rAPC)对接种H22肝癌细胞小鼠的抑瘤活性及其免疫作用。方法:昆明小鼠随机分为5组(10只/组),即模型组、rAPC低、中、高剂量组(25,50,100mg/kg·d)、环磷酰胺组(CY对照组)。建立小鼠肝癌H22移植瘤模型,次日除模型组外,其余4组分别以不同剂量的rAPC、CY灌胃,于15d后处死,完整剥离出肿瘤、胸腺、脾脏,准确称重,计算抑瘤率、胸腺指数和脾指数,并采用放免法(RIA)测定血清中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的水平。结果:rAPC低剂量组小鼠H22肿瘤质量增长较模型组缓慢(P<0.05),中、高剂量组较模型组显著缓慢(P<0.01),抑瘤率分别为25.2%、36.7%、43.1%;rAPC各剂量组能升高胸腺指数、脾指数和血清中细胞因子IL-6、TNF-α的水平。结论:rAPC可有效抑制H22肝癌的生长,促进小鼠胸腺和脾脏的生长发育,提高小鼠的免疫功能,从而抑制肿瘤的生长。  相似文献   

5.
目的:观察重组别藻蓝蛋白(rAPC)对接种H22肝癌细胞小鼠的抑瘤活性及其免疫作用.方法:昆明小鼠随机分为5组(10只/组),即模型组、rAPC低、中、高剂量组(25,50,100mg/kg·d)、环磷酰胺组(CY对照组).建立小鼠肝癌1422移植瘤模型,次日除模型组外,其余4组分别以不同剂量的rAPe、CY灌胃,于15d后处死,完整剥离出肿瘤、胸腺、脾脏,准确称重,计算抑瘤率、胸腺指数和脾指数,并采用放免法(PIA)测定血清中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的水平.结果:rAPC低剂量组小鼠H22肿瘤质量增长较模型组缓慢(P<0.05),中、高剂量组较模型组显著缓慢(P<0.01),抑瘤率分别为25.2%、36.7%、43.1%;rAPC各剂量组能升高胸腺指数、脾指数和血清中细胞因子IL-6、TNF-α的水平.结论:rAPC可有效抑制H22肝癌的生长,促进小鼠胸腺和脾脏的生长发育,提高小鼠的免疫功能,从而抑制肿瘤的生长.  相似文献   

6.
王超儀  包海鹰 《菌物研究》2013,11(3):196-201
对6种"桑黄"的石油醚提取物进行了抗肿瘤体内试验,测定其对H22荷瘤小鼠抑瘤率、免疫器官指数、免疫因子含量和生存率的影响。试验结果表明:粗毛纤孔菌、鲍姆木层孔菌、火木层孔菌和瓦宁木层孔菌的石油醚提取物高、低剂量(100,50 mg/kg)以及黑壳目层孔菌石油醚提取物高剂量(100 mg/kg)对肿瘤均具有一定抑制作用,抑瘤率均〉40%;瓦宁木层孔菌石油醚提取物低剂量组(50 mg/kg)的抑瘤效果最佳,为76.82%,其脾指数、胸腺指数均明显高于阳性组(P〈0.01),IL 2的含量也明显高于对照组和阳性组,能延长小鼠的生存期;椭圆嗜蓝孢孔菌石油醚提取物也具有一定的抑瘤效果,高、低剂量(100,50 mg/kg)抑瘤率分别为39.30%和36.17%。  相似文献   

7.
探讨凤丹籽油对小鼠移植性肿瘤H22的抑瘤作用及机制。建立肝癌H22移植性肿瘤模型小鼠,随机分为正常组、模型组、5-氟尿嘧啶(5-FU)阳性对照组、凤丹籽油高、中、低剂量组,给药10 d后处死。结果表明:低、中、高剂量组的抑瘤率分别是18.4%、26.9%、34.7%,具有较好量效关系。与模型组相比,低、中、高剂量组能不同程度提高胸腺、脾脏指数,降低AST、ALT、ALP,增加WBC;降低TE活性和BCL-2表达,显著提高BAX表达。以上结果表明,高剂量凤丹籽油对H22荷瘤小鼠有明显的抑瘤作用,其机制可能是通过调节免疫功能和抑制TE活性、BCL-2表达,提高BAX表达而发挥肿瘤抑制作用。  相似文献   

8.
目的探讨肿瘤坏死因子相关的凋亡诱导配体(tumor necrosis factor-related apoptosis inducing ligand,TRAIL)联合顺铂(cisplatin,DDP)对小鼠移植型肝癌的抑制作用及机制。方法将H22小鼠移植型肝癌模型随机分为生理盐水组、TRAIL组、TRAIL+DDP组和DDP组,称取瘤重并分析抑瘤率,Hoechst 33342荧光染色法检测细胞凋亡,免疫组织化学染色检测Caspase-3表达。结果与生理盐水组比较,TRAIL、DDP对小鼠移植型肝癌生长具有明显的抑制作用(P<0.05);TRAIL与DDP联合用药具有增效作用(P<0.05),可明显提高肝癌细胞的凋亡率(P<0.05)、上调Caspase-3表达(P<0.01)。结论 TRAIL与DDP联合用药对小鼠移植型肝癌生长具有协同抑制作用,其机制可能与其协同促进Caspase-3的表达有关。  相似文献   

9.
梁伟  包海鹰 《菌物学报》2011,30(4):630-635
采用梯度提取法对山野木层孔菌子实体进行提取,得到石油醚层、甲醇层及水层3 种提取物及石油醚层中获得化合物4,6,8(14),22(23)-四烯-3-酮-麦角甾烷,并采用H22 荷瘤小鼠进行体内抗肿瘤活性研究,以抑瘤率、免疫器官指数、免疫因子为指标检测抗肿瘤活性。结果表明,石油醚高剂量组(100mg/kg)、单体化合物中剂量组(7.5mg/kg)抑制率分别为62.21%、57.67%;脾指数、胸腺指数均高于对照组和环磷酰胺(CTX)组,白介素-2(IL-2)的含量明显高于对照组和环磷酰胺(CTX)组(P<0.01);肿瘤坏死因子-α(TNF-α)含量明显低于对照组(P<0.01)。因此认为上述石油醚提取物和单体化合物对H22荷瘤小鼠肿瘤有抑制作用,并且均能改善小鼠的免疫功能。  相似文献   

10.
软骨多糖抑制Hca-F肝癌细胞转移的初步研究   总被引:2,自引:0,他引:2  
目的:研究软骨多糖抑制小鼠淋巴结高转移肝癌细胞Hca-F侵袭转移的作用。方法:以615近交系小鼠右脚垫皮下注射肝癌细胞Hca-F建立转移模型,设模型组和给药组。检测软骨多糖抑瘤率、淋巴道转移抑制率、淋巴结石蜡切片HE染色观察肿瘤细胞侵袭情况和采用ELISA试剂盒测定血清中TNF-α的含量。结果:软骨多糖具有明显的抑瘤作用,抑瘤率达61.9%;淋巴结转移抑制率为22.2%;通过比较模型组和给药组瘤细胞转移部位淋巴结的HE染色,发现给药组转移情况明显低于模型组;ELISA检测表明给药组血清中TNF-α的含量明显低于模型组(P<0.05)。结论:软骨多糖一定程度上能够抑制肝癌细胞Hca=F向周围淋巴结转移,为开发治疗恶性肿瘤的药物提供了选择。  相似文献   

11.
Aspergillus species can cause mycoses in human and animals. Previously, we demonstrated that A. fumigatus conidia from a human isolate inhibited apoptosis in human pneumocytes and bronchial epithelial cells. In the current study, we studied the effects of A. fumigatus conidia non-human origin and A. flavus, A. nidulans, A. niger and A. oryzae conidia on human cells apoptosis. Human pneumocytes or bronchial epithelial cells were simultaneously exposed to apoptotic inductors and aspergilli conidia. The cell cultures were analyzed by flow cytometry, immunoblotting, and examination of nuclear morphology. Similar to A. fumigatus conidia, A. flavus conidia inhibited cellular apoptosis while A. nidulans, A. niger and A. oryzae conidia did not affect apoptosis. We further studied the species specificity of conidia: there were no differences in the inhibition of apoptosis by A. fumigatus conidia from either human or bird isolates. In order to determine whether the inhibition of apoptosis by conidia is limited to certain strains, the effect on human cell apoptosis of different A. fumigatus human clinical isolates and A. fumigatus of environmental origin was evaluated. All A. fumigatus isolates inhibited apoptosis; an anti-apoptotic factor was released by conidia. For TNF-induced apoptosis, the anti-apoptotic effect of conidia of all isolates was found to be associated with a reduction of caspase-3 in human cells. The results suggest that suppression of apoptosis may play a role in reducing the efficacy of host defense mechanisms during infection with Aspergillus species. F. Féménia and D. Huet made an equal contribution to this work.  相似文献   

12.
Excess ER stress induces caspase-12 activation and/or cytochrome c release, causing caspase-9 activation. Little is known about their relationship during ER stress-mediated cell death. Upon ER stress, P19 embryonal carcinoma (EC) cells showed activation of various caspases, including caspase-3, caspase-8, caspase-9, and caspase-12, and extensive DNA fragmentation. We examined the relationship between ER stress-mediated cytochrome c/caspase-9 and caspase-12 activation by using caspase-9- and caspase-8-deficient mouse embryonic fibroblasts and a P19 EC cell clone [P19-36/12 (-) cells] lacking expression of caspase-12. Caspase-9 and caspase-8 deficiency inhibited and delayed the onset of DNA fragmentation but did not inhibit caspase-12 processing induced by ER stress. P19-36/12 (-) cells underwent apoptosis upon ER stress, with cytochrome c release and caspase-8 and caspase-9 activation. The dominant negative form of FADD and z-VAD-fmk inhibited caspase-8, caspase-9, Bid processing, cytochrome c release, and DNA fragmentation induced by ER stress, suggesting that caspase-8 and caspase-9 are the main caspases involved in ER stress-mediated apoptosis of P19-36/12 (-) cells. Caspase-8 deficiency also inhibited the cytochrome c release induced by ER stress. Thus, in parallel with the caspase-12 activation, ER stress triggers caspase-8 activation, resulting in cytochrome c/caspase-9 activation via Bid processing.  相似文献   

13.
Human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) disease is a chronic neuroinflammatory disease, which is associated with HTLV-1 infection. There is no effective and satisfactory treatment of HAM/TSP. It has been shown that curcumin exhibits modulatory effects on apoptosis and cytotoxicity-related molecules in HAM/TSP patients. In the present study, we examined the effect of curcumin on the gene expression of caspase-8, caspase-10, and anti-apoptotic protein c-FLIP, in HAM/TSP patients. Furthermore, we compared the expression of these molecules between HAM/TSP and asymptomatic carriers. Real-time PCR was performed to examine the mRNA expression of caspase-8, caspase-10, and c-FLIP in studied groups. The mRNA expression of caspase-8 and caspase-10 was similar before and after curcumin treatment in HAM/TSP patients (P > 0.05). The mRNA expression of c-FLIPL and c-FLIPs was higher after curcumin treatment compared with before treatment and significant differences were observed between the two groups (P = 0.004 and P = 0.044, respectively). The mRNA expression levels of caspase-8, caspase-10, c-FLIPL, and c-FLIPs were not statistically significant between HAM/TSP patients and asymptomatic carriers (P < 0.05). In conclusion, our results showed that curcumin increased the expression of c-FLIP in HAM/TSP patients which might suggest that, this molecule is involved in the apoptosis of HTLV-1-infected cells. Further studies with large sample size could be useful to clarify the role of this supplement in HAM/TSP patients.  相似文献   

14.
Distinct apoptotic response of the type I/type II cells against Fas-ligand stimulation is considered to arise from the difference in dominant signaling pathways involved. In the type I cells, apoptotic signaling predominantly takes place via the direct activation of caspase-3 by activated caspase-8 (D channel) while mitochondrial pathway (M channel) plays a major role in the type II cells. To elucidate the selection mechanism of dominant pathway, we carried out systematic model analysis of the Fas signaling-induced apoptosis network. An increase in the expression level of caspase-8 induced a switch of dominant pathway from M- to D-channel (M–D transition), showing a phenotypic change from type II to type I cells. With the aid of sensitivity analysis and kinetic considerations, we succeeded in constructing a minimal network model relevant for the M–D transition, which revealed that mechanistic origin of the transition lies in the competition between the activated forms of caspase-8 and caspase-9 for their common substrate caspase-3. The pathway dominance was found to be primarily controlled by the balance between the activation rate of caspase-8 and the initial level of caspase-9. In the full network model, we showed that differential formation ability of the death-inducing signaling complex (DISC) can also induce M–D transition, in accordance with the experimental observations.  相似文献   

15.
Apoptosis, or programmed cell death, plays a central role in the development and homeostasis of an organism. The breakdown of cellular proteins in apoptosis is mediated by caspases, which comprise a highly conserved family of cysteine proteases with specificity for aspartic acid residues at the P1 positions of their substrates. Multiple lines of evidence show that caspase-9 is critical for an apoptosis pathway mediated via the mitochondria. In this study, the three-dimensional structure of the catalytic domain of caspase-9 and its interaction with the inhibitor acetyl-Asp-Val-Ala-Asp fluoromethyl ketone (Ac-DVAD-fmk) have been predicted by a segment matching modeling procedure. As expected, the predicted caspase-9 structure shows both a high similarity in the overall folding topology and remarkable differences in the surface loop regions as compared to other caspase family members such as caspase-1, -3 and -8, for which crystal structures have been determined. This kind of comparative analysis reflects the convergence-divergence duality among the caspases. Moreover, some subtle differences have been observed between caspase-9 and caspase-3 in the subsite contacts with the covalently linked inhibitor Ac-DVAD-fmk. Based on the X-ray structural analysis of caspase-8, a main chain carbonyl oxygen appears to be involved in a catalytic triad with the active site Cys and His residues. The corresponding carbonyl oxygen in caspase-9, together with other expected features of the catalytic apparatus, appears in our model. The predicted structure of caspase-9 can serve as a reference for subsite analysis relative to rational design of highly selective caspase inhibitors for therapeutic application.  相似文献   

16.
Nicotinamide (vitamin B3) reduces the infarct volume following focal cerebral ischemia in rats; however, its mechanism of action has not been reported. After cerebral ischemia and/or reperfusion, reactive oxygen species (ROS) and reactive nitrogen species may be generated by inflammatory cells through several cellular pathways, which can lead to intracellular calcium influx and cell damage. Therefore, we investigated the mechanisms of action of nicotinamide in neuroprotection under conditions of hypoxia/reoxygenation. Results showed that nicotinamide significantly protected rat primary cortical cells from hypoxia by reducing lactate dehydrogenase release with 1 h of oxygen-glucose deprivation (OGD) stress. ROS production and calcium influx in neuronal cells during OGD were dose-dependently diminished by up to 10 mM nicotinamide (p<0.01). This effect was further examined with OGD/reoxygenation (H/R). Cells were stained with the fluorescent dye 4,6-diamidino-2-phenylindole (DAPI) or antibodies against anti-microtubule-associated protein-2 and cleaved caspase-3. Apoptotic cells were studied using Western blotting of cytochrome c and cleaved caspase-3. Results showed that vitamin B3 reduced cell injury, caspase-3 cleavage and nuclear condensation (DAPI staining) in neuronal cells under H/R. In addition, nicotinamide diminished c-fos andzif268 immediate-early gene expressions following OGD. Taken together, these results indicate that the neuroprotective effect of nicotinamide might occur through these mechanisms in this in vitro ischemia/reperfusion model.  相似文献   

17.
Expression of HSV-1 genes leads to the induction of apoptosis in human epithelial HEp-2 cells but the subsequent synthesis of infected cell protein prevents the process from killing the cells. Thus, viruses unable to produce appropriate prevention factors are apoptotic. We now report that the addition of either a pancaspase inhibitor or caspase-9-specific inhibitor prevented cells infected with an apoptotic HSV-1 virus from undergoing cell death. This result indicated that HSV-1-dependent apoptosis proceeds through the mitochondrial apoptotic pathway. However, the pancaspase inhibitor did not prevent the release of cytochrome c from mitochondria, implying that caspase activation is not required for this induction of cytochrome c release by HSV-1. The release of cytochrome c was first detected at 9 hpi while caspase-9, caspase-3 and PARP processing were detected at 12 hpi. Finally, Bax accumulated at mitochondria during apoptotic, but not wild type HSV-1 infection. Together, these findings indicate that HSV-1 blocks apoptosis by precluding mitochondrial cytochrome c release in a caspase-independent manner and suggest Bax as a target in infected human epithelial cells.  相似文献   

18.
线粒体促凋亡因子Omi/HtrA2在乳腺癌中的表达及意义   总被引:1,自引:0,他引:1  
目的本文旨在通过检测促凋亡分子Omi/HtrA2在乳腺良恶性肿瘤组织中的表达,探讨其与乳腺癌发病的关系及临床意义.方法采用免疫组化EnVinsion system法检测63例乳腺癌及37例乳腺纤维腺瘤组织中Omi/HtrA2的表达情况,同时检测这些组织中Caspase-3蛋白的表达.结果 Omi/HtrA2在乳腺纤维腺瘤中表达显著低于乳腺癌中的表达(P<0.05),而Caspase-3则在乳腺纤维腺瘤中表达显著高于乳腺癌中的表达(P<0.05),但二者的表达与乳腺癌的临床分期均无明显相关性(P>0.05).结论线粒体促凋亡蛋白Omi/HtrA2的在乳腺癌中高表达与其发生发展有关.  相似文献   

19.
Pseudomonas aeruginosa is a gram-negative opportunistic pathogen that is cytotoxic towards a variety of eukaryotic cells. To investigate the effect of this bacterium on monocyte, we infected human U937 cells with the P. aeruginosa strain in vitro. To explore the expression of Bcl-2 and Bax as well as caspase-3/9 activation in the apoptosis of human U937 cells induced by P. aeruginosa, Hoechst 33258 staining and Giemsa staining as well as Flow cytometry analysis were used to determine the rate of apoptosis, and the expressions of Bcl-2 and Bax were assayed by RT-PCR and Western blotting respectively. Bax protein conformation change was assayed by immunoprecipitation. Cytochrome c release was measured by Western blotting. Moreover, exposure of U937 cells to P. aeruginosa measured caspase-3/9 activity. It was found that the apoptosis of human U937 cells could be induced by Pseudomonas aeruginosa in a dose- and time-dependent manner. Also, there were a tendency of alterations with an increased expression level of Bax and a reduced expression level of Bcl-2, increased levels of cytochrome c release, and also with an increased activation of caspase-3/9 and Bax protein conformation change. For the evaluation of the role of caspases, caspase-3/9 inhibitors Z-DEVD-FMK and Z-LEHD-FMK respectively were used. The results were further confirmed by the observation that the caspase inhibitors Z-DEVD-FMK and Z-LEHD-FMK blocked P. aeruginosa-induced U937 apoptosis. It is concluded that P. aeruginosa can induce apoptosis with an up-regulated expression of Bax and a down-regulated expression of Bcl-2, which resulted in increased levels of cytochrome c release and increased caspase-3 and -9 in human U937 cells.  相似文献   

20.
目的:探讨PIG11、Caspase-3蛋白在胃癌中的表达及临床意义。方法:采用免疫组织化学SP法检测80例胃癌组织、36例正常胃黏膜组织、30例肠上皮化生组织及31例异型增生组织中PIG11、Caspase-3蛋白的表达水平,并分析其表达与胃癌临床病理特征的关系及两者之间的相关性。结果:胃癌组织中PIG11、Caspase-3蛋白的阳性表达率均显著低于正常胃黏膜、肠上皮化生及异型增生组织(P0.01);PIG11、Caspase-3蛋白表达水平与胃癌的分化程度、临床分期、有无淋巴结转移及远处转移密切相关(P0.05),但与患者的年龄、性别及肿瘤的浸润深度无关(P0.05);PIG11、Caspase-3蛋白在胃癌组织中的表达呈正相关(r=0.859,P0.01)。结论:PIG11、Caspase-3蛋白在胃癌中明显表达下调,且与胃癌的分化程度、临床分期、有无淋巴结转移及远处转移密切相关,可能作为胃癌预后评估的参考指标。PIG11表达下调可能通过抑制Caspase-3的表达促进胃癌的发生和发展。  相似文献   

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