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1.
为研究新合成的靶向抗肿瘤肽RGD-T-La(S)、RGD-T-La(FS)对小鼠黑色素瘤B16细胞增殖及其黑色素合成的影响,本研究将T-La (S)、T-La (FS)与RGD (精氨酸-谷氨酸-天冬氨酸)小分子蛋白质偶联,合成新的靶向抗肿瘤肽RGD-T-La (S)、RGD-T-La (FS)。通过CCK8法检测多肽对B16细胞增殖的影响;微量酶标法检测多肽作用于B16细胞后乳酸脱氢酶(LDH)含量变化;透射电镜观察多肽作用B16细胞后的超微结构;流式细胞仪检测多肽对B16细胞周期的影响;NaOH裂解法和L-Dopa氧化法分析多肽对黑色素合成含量和酪氨酸酶活性的影响;荧光定量PCR (q-PCR)法分析多肽对黑色素合成关键因子酪氨酸酶(TYR)和小眼相关转录因子(MITF)基因转录水平的影响。结果显示,RGD-T-La(S)、RGD-T-La (FS)在10μg/mL时能够显著抑制B16细胞的增殖,且呈现时间浓度依赖性;RGD嵌合体肽在20μg/mL时能够显著增加B16细胞中LDH含量,且呈现浓度依赖性;透射电镜结果显示RGD嵌合体肽作用B16后,细胞出现自噬体及线粒体自噬现象;同时RGD嵌合体肽对酪氨酸酶活性和细胞黑色素蛋白的生成具有明显的抑制作用,显著降低TYR和MITF基因的转录水平。上述结果表明,RGD嵌合体肽在体外具有诱导细胞凋亡,抑制B16细胞增殖的作用,能够促进抗肿瘤肽T-La (FS)对肿瘤细胞的靶向杀伤作用。本实验为研究RGD嵌合体肽RGD-T-La (S)和RGD-T-La (FS)靶向抗肿瘤的作用机制以及为临床相关抗肿瘤药物的研发提供科学依据。  相似文献   

2.
试验旨在研究抗菌肽Temprine-La(S)(T-La(S))、Temprine-La(FS)(T-La(FS))、RGD-T-La(S)和RGD-T-La(FS)对2型猪链球菌(SS2)生物被膜形成的抑制作用。通过结晶紫染色法(CV)检测SS2生物被膜形成能力;微量稀释法测定抗菌肽对SS2生物被膜的最小生物被膜抑菌浓度(MBIC)和最小生物被膜杀菌浓度(MBEC);结晶紫染色法和扫描电镜(SEM)检测抗菌肽对SS2生物被膜形成的影响;XTT法检测抗菌肽对SS2生物被膜代谢活性的影响;苯酚硫酸法检测抗菌肽对SS2生物被膜胞外多糖含量的影响;建立猪链球菌-斑马鱼感染模型,HE染色法观察T-La(FS)对斑马鱼脑组织病理变化的影响;实时荧光定量PCR法分析抗菌肽对SS2生物被膜相关基因及对斑马鱼炎性细胞因子基因转录水平的影响。结果显示,SS2具有良好的生物被膜形成能力;T-La(S)、RGD-T-La(S)、T-La(FS)和RGD-T-La(FS)对SS2生物被膜的MBIC分别为31.3、15.6、7.8和15.6μg/mL;MBEC分别为62.6、31.2、15.6和31.2μg/mL;结晶紫染色结果表明,抗菌肽对SS2生物被膜的形成有抑制作用;扫描电镜结果显示,抗菌肽使SS2生物被膜中的细菌数量和生物被膜的形态发生明显变化,细胞外基质大量减少;XTT法结果显示,抗菌肽可显著降低SS2生物被膜的代谢活性;苯酚硫酸法结果显示,抗菌肽能有效抑制SS2生物被膜合成胞外多糖;实时荧光定量PCR结果表明,抗菌肽作用后降低了SS2生物被膜基因的转录水平;T-La(FS)作用后TLR2、MyD88及促炎性细胞因子基因的转录水平显著或极显著降低(P<0.05;P<0.01),抗炎性细胞因子基因的转录水平显著或极显著升高(P<0.05;P<0.01)。抗菌肽主要通过影响生物被膜相关基因转录水平和阻断胞外多糖的合成与分泌来抑制SS2生物被膜的形成,其中T-La(FS)可能通过抑制TLR2信号通路中TLR2和MyD88分子表达,抑制炎性细胞因子的释放,减轻脑膜炎的炎性反应。  相似文献   

3.
通过筛选牛蛙皮肤cDNA文库得到具有较强抗菌抗肿瘤活性肽Catesbeianin-1a,合成其成熟肽氨基酸序列,MIC法测定抑菌活性结果表明,Catesbeianin-1a对临床常见的致病菌具有较强的抑菌活性,其中对猪链球菌2型的MIC为2.5mg/L,且对兔红细胞几乎无溶血性。MTT法测定多肽抗肿瘤细胞活性,结果 Catesbeianin-1a对胃癌细胞和肝癌细胞的抑杀活性很强,对肝癌细胞SGC7901的IC50为0.845mg/L。制作透射电镜超薄切片,利用透射电镜观察活性肽对细菌和肿瘤细胞超微结构的影响,旨在初步探讨牛蛙皮肤活性肽Catesbeianin-1a抗菌、抗肿瘤的作用机制,并以Catesbeianin-1a为基础进行分子改造来提高其抗肿瘤的靶向性并降低其毒性。  相似文献   

4.
试验旨在研究抗菌肽Temprine-La(S)(T-La(S))、Temprine-La(FS)(T-La(FS))、RGD-T-La(S)和RGD-T-La(FS)对2型猪链球菌(SS2)生物被膜形成的抑制作用。通过结晶紫染色法(CV)检测SS2生物被膜形成能力;微量稀释法测定抗菌肽对SS2生物被膜的最小生物被膜抑菌浓度(MBIC)和最小生物被膜杀菌浓度(MBEC);结晶紫染色法和扫描电镜(SEM)检测抗菌肽对SS2生物被膜形成的影响;XTT法检测抗菌肽对SS2生物被膜代谢活性的影响;苯酚硫酸法检测抗菌肽对SS2生物被膜胞外多糖含量的影响;建立猪链球菌-斑马鱼感染模型,HE染色法观察T-La(FS)对斑马鱼脑组织病理变化的影响;实时荧光定量PCR法分析抗菌肽对SS2生物被膜相关基因及对斑马鱼炎性细胞因子基因转录水平的影响。结果显示,SS2具有良好的生物被膜形成能力;T-La(S)、RGD-T-La(S)、T-La(FS)和RGD-T-La(FS)对SS2生物被膜的MBIC分别为31.3、15.6、7.8和15.6 μg/mL;MBEC分别为62.6、31.2、15.6和31.2 μg/mL;结晶紫染色结果表明,抗菌肽对SS2生物被膜的形成有抑制作用;扫描电镜结果显示,抗菌肽使SS2生物被膜中的细菌数量和生物被膜的形态发生明显变化,细胞外基质大量减少;XTT法结果显示,抗菌肽可显著降低SS2生物被膜的代谢活性;苯酚硫酸法结果显示,抗菌肽能有效抑制SS2生物被膜合成胞外多糖;实时荧光定量PCR结果表明,抗菌肽作用后降低了SS2生物被膜基因的转录水平;T-La(FS)作用后TLR2、MyD88及促炎性细胞因子基因的转录水平显著或极显著降低(P<0.05;P<0.01),抗炎性细胞因子基因的转录水平显著或极显著升高(P<0.05;P<0.01)。抗菌肽主要通过影响生物被膜相关基因转录水平和阻断胞外多糖的合成与分泌来抑制SS2生物被膜的形成,其中T-La(FS)可能通过抑制TLR2信号通路中TLR2和MyD88分子表达,抑制炎性细胞因子的释放,减轻脑膜炎的炎性反应。  相似文献   

5.
<正>抗菌肽是一类防御性生物活性物质,广泛存在于细菌、植物、昆虫及动物中,具有抗菌、抗病毒及抗原虫作用。此外,抗菌肽还具有较强的抗肿瘤活性。抗菌肽的抗肿瘤机制特殊,可以选择性地作用于肿瘤细胞,通过破坏细胞膜、细胞骨架、细胞器等达到杀伤肿瘤细胞的目的,具有对动物正常细胞毒性较低,作用迅速,不易产生耐药性的特点[1]。基于以上特点,寻  相似文献   

6.
试验旨在研究新发现的两种牛蛙活性肽对人肺癌细胞NCI-H446、人乳腺癌细胞MCF-7及小鼠白血病细胞K562 3种肿瘤细胞体外增殖的影响,为新的多肽抗肿瘤药筛选提供依据。本试验利用圆二色谱(CD)法检测两种新牛蛙活性肽的二级结构,通过MTS细胞毒试验测定不同浓度的两种新牛蛙活性肽对人肺癌细胞NCI-H446、人乳腺癌细胞MCF-7及小鼠白血病细胞K562 3种瘤细胞体外增殖的影响。圆二色谱法结果显示,Temporin-Lb的二级空间结构为聚脯氨酸Ⅱ型螺旋(PPⅡ)结构,Catesbeianin-1a的二级空间结构为无规则卷曲。MTS细胞毒试验结果显示,给予Catesbeianin-1a的3种瘤细胞培养24 h后,瘤细胞形态无明显变化,正常增殖,而给予Temporin-Lb的3种瘤细胞培养24 h后,瘤细胞发生皱缩、细胞变圆、脱落甚至死亡,增殖受到抑制,其中对Temporin-Lb在4~40 μmol/L浓度范围内对小鼠白血病细胞K562的抑制效果最为明显。结果表明,新牛蛙活性肽Temporin-Lb具有一定的抑瘤作用,Catesbeianin-1a对瘤细胞的体外增殖没有明显影响。  相似文献   

7.
冯挺  胡福良 《蜜蜂杂志》2020,40(9):17-20
蜂毒肽是蜂毒中主要的活性成分,具有广泛的抗肿瘤、抗炎症、镇痛、抗病毒等生理活性,极具潜在的临床药用价值.对蜂毒肽的抗肿瘤作用机制,主要包括对肿瘤细胞的直接杀伤效应,诱导肿瘤细胞发生损伤和凋亡,影响肿瘤细胞的生物学行为,改变肿瘤细胞生存环境和免疫调节作用等进行了综述,并简要分析了蜂毒肽在实际应用中所面临的挑战.  相似文献   

8.
苦马豆素抗肿瘤作用研究进展   总被引:7,自引:1,他引:6  
苦马豆素(SW)是一种吲哚里西啶生物碱,最早是从灰苦马豆中分离得到,是疯草类植物的主要毒性成分.它能抑制肿瘤细胞表面糖蛋白的表达,从而抑制肿瘤细胞的生长与转移.此外,SW能促进脾细胞增殖,增强巨噬细胞对肿瘤细胞的杀伤活性,还能促进机体淋巴细胞活性升高,刺激机体骨髓细胞增殖,增强机体杀灭肿瘤细胞的能力.由于SW具有很好的抗肿瘤活性和免疫增强作用,已引起国内外学者的广泛关注,并作为抗肿瘤药物筛选的后备药物.目前,国外SW抗肿瘤药物的研发已进入Ⅲ期临床试验阶段,而国内才刚起步.论文主要介绍了SW抗肿瘤作用及其临床治疗效果,并对SW下一步研究重点及应用前景进行了展望.  相似文献   

9.
抗菌肽的研究进展   总被引:1,自引:0,他引:1  
抗菌肽是广泛存在于自然界生物中的具有广谱抗菌、抗病毒、抑制杀伤肿瘤细胞等作用的多肽。本文介绍了抗菌肽的结构,抗菌肽的生物学活性,抗菌肽的作用机理和作用机制,以及抗菌肽的应用和前景。  相似文献   

10.
抗菌肽研究进展及其在饲料中的应用   总被引:1,自引:0,他引:1  
抗菌肽(anti—bacterial peptides),又称抗微生物肽(peptide antibiotics),是生物体在抵抗病原微生物的防御反应过程中产生的一种具有抗微生物功能的小分子多肽,它们多为1345个氨基酸组成的短肽(肖建光等,2005;Bulet等,2004)。抗菌肽广泛存在于植物、细菌、动物体内,是生物先天性免疫的重要效应分子。抗菌肽除具有广谱的抗菌活性外,还具有抗原虫、抗真菌、抗病毒和抑制或杀伤肿瘤细胞等作用。动物抗菌肽与青霉素等传统抗生素作用机制完全不同,病原菌不易产生对抗菌肽的耐药性。此外,抗菌肽一般情况下只作用于原核细胞和发生病变的真核细胞,而对正常的真核细胞无影响。  相似文献   

11.
喹噁啉类药物是畜牧生产中大量使用的抗菌促生长添加剂,同时在医药领域也进行着大量的研究,在国际上得到广泛的重视。主要介绍了目前国内外在喹噁啉类药物在抗肿瘤和抗菌生物活性方面作用的研究进展,并且探讨了其作用的机理。  相似文献   

12.
龙葵在我国大部分地区均有分布。龙葵全草含有多种化学成分,最重要的是生物碱类和多糖,具有抗肿瘤、抗炎、抗过敏、抗菌等作用,尤其在抗肿瘤方面的作用成为近年来研究的热点。笔者等对龙葵的抗肿瘤作用方面的研究进行综述。  相似文献   

13.
We have shown that pyrimidinone molecule, 2 amino-5-iodo-6-phenyl-4-pyrimidinone (AIPP) after regional administration, displayed both prophylactic and therapeutic effect on ascitic mammary adenocarcinoma, ACA-755. The antitumor effect was mediated by natural killer (NK) cells, since depletion of this lymphocyte population resulted in abrogation of AIPP-induced tumor resistance. This observation confirms the role of NK cells in antitumor immunity and suggests that AIPP may be therapeutically beneficial also in man.  相似文献   

14.
研究疯草内生真菌(Undifilum oxytropis),次级代谢产物成分与活性,通过GC-MS对菌丝体及发酵液进行了分析,并通过MTT法测定抗肿瘤活性。结果表明,菌丝体和发酵液中均以烷烃和酯类物质为主,菌丝体中检出活性物质角鲨烯(0.863%);菌丝体对HCT-8人回盲肠癌细胞和OS-RC-2人肾癌细胞抑制率均较高,发酵液对HCT-8人回盲肠癌细胞抑制率相对较弱。  相似文献   

15.
We have reported that the ascitic growth of a transplantable T cell lymphoma of spontaneous origin, designated as Dalton's lymphoma (DL), is associated with a concomitant immunosuppression. We have also reported that progressive in vivo growth of DL resulted in an inhibition of macrophage functions. In present investigation we report that physical exercise by DL-bearing mice, on a treadmill on a daily basis for various time durations for 10 days, increased the life span along with an inhibition of tumor growth. A significant decrease in the volume of ascitic fluid and number of cells in the tumor was obtained in mice, which underwent exercise. DL cells obtained from exercised groups showed a decreased proliferation in vitro. An augmentation in the percent of cells showing apoptotic morphology and percent specific DNA fragmentation was observed, suggesting that physical exercise increased the incidence of apoptosis in tumor cells. Moreover, macrophages obtained from tumor-bearing mice, which underwent exercise training, showed an augmented tumoricidal activity and production of tumoricidal molecules like interleukin-1 (IL-1), tumor necrosis factor (TNF) and nitric oxide (NO). On the basis of this study it is suggested that the regression of tumor growth consequent to physical exercise training of tumor bearing host, may be due to an exercise-dependent augmentation of macrophage tumoricidal functions.  相似文献   

16.
OBJECTIVE: To describe the surgical technique of vertebrectomy with bone allograft fusion and the use of antitumor vaccine for the treatment of a primary vertebral neoplasm in a dog. STUDY DESIGN: Case Report. ANIMALS OR SAMPLE POPULATION: A 3 year old 32 kg female spayed mixed breed dog with progressive paraplegia. METHODS: Myelography was performed to identify an L5 lytic lesion with spinal cord compression. A dorsal laminectomy was performed to decompress the spinal cord and obtain biopsies. Pathologic fracture of the vertebral body two days later was treated with L5 vertebrectomy, cortical allograft implantation, and bilateral plating from L4 to L6. Tumor samples were used to create an autologous cytokine-gene-engineered tumor cell vaccine. Recheck radiographs and neurologic examinations were obtained 1, 2, 7, and 13 months after surgery. RESULTS: The histopathologic diagnosis was fibrosarcoma. Although slight osteopenia of the allograft was noted thirteen months after surgery, the allograft and plate fixation remained stable. The patient tolerated the antitumor vaccination protocol well. Two years after the procedures the dog was able to ambulate normally but remained urinary and fecal incontinent. CONCLUSIONS AND CLINICAL RELEVANCE: Vertebrectomy and cortical allograft implantation with plating permitted this patient to return to a functional lifestyle with its owners.  相似文献   

17.
《中国蜂业》2020,(5):63-66
蜂胶具有较好的抗肿瘤功效,但其功效成分及其作用机理还未完全阐明。本文研究了中国蜂胶乙醇提取物(EECP)(100μg/ml)及其主要组分(咖啡酸苯乙酯、白杨素、芹菜素、高良姜素)(80μM)抑制两种肺癌细胞(A549和H1299)的作用功效及机理。通过transwell实验,发现EECP及其主要组分显著抑制A549和H1299细胞的浸润;通过Hoechst33258染色和Western blotting检测,发现EECP及其主要组分显著促进两种肺癌细胞的凋亡,上调caspase 3水平,降低未剪切PARP蛋白水平,而EECP及其主要组分促进A549和H1299两种肺癌细胞凋亡与上调肿瘤细胞内活性氧水平、降低线粒体膜电位有关。蜂胶及其主要组分是潜在的抗肿瘤天然活性物质。  相似文献   

18.
19.
Canine prostate cancer (cPCa) is a malignant neoplasm with no effective therapy. The BRAF V595E mutation, corresponding to the human BRAF V600E mutation, is found frequently in cPCa. Activating BRAF mutations are recognized as oncogenic drivers, and blockade of MAPK/ERK phosphorylation may be an effective therapeutic target against BRAF-mutated tumours. The aim of this study was to establish a novel cPCa cell line and to clarify the antitumor effects of MEK inhibitors on cPCa in vitro and in vivo. We established the novel CHP-2 cPCa cell line that was derived from the prostatic tissue of a cPCa patient. Sequencing of the canine BRAF gene in two cPCa cell lines revealed the presence of the BRAF V595E mutation. MEK inhibitors (trametinib, cobimetinib and mirdametinib) strongly suppressed cell proliferation in vitro, and trametinib showed the highest efficacy against cPCa cells with minimal cytotoxicity to non-cancer COPK cells. Furthermore, we orally administered 0.3 or 1.0 mg/kg trametinib to CHP-2 xenografted mice and examined its antitumor effects in vivo. Trametinib reduced tumour volume, decreased phosphorylated ERK levels, and lowered Ki-67 expression in xenografts in a dose-dependent manner. Although no clear adverse events were observed with administration, trametinib-treated xenografts showed osteogenesis that was independent of dosage. Our results indicate that trametinib induces cell cycle arrest by inhibiting ERK activation, resulting in cPCa tumour regression in a dose-dependent manner. MEK inhibitors, in addition to BRAF inhibitors, may be a targeted agent option for cPCa with the BRAF V595E mutation.  相似文献   

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