蛇毒细胞毒素抗肿瘤作用的研究进展

蛇毒细胞毒素是蛇毒的主要毒性组分之一,约占蛇毒总蛋白含量的25%～60%,具有广泛的生物学活性,能引起可兴奋性细胞如骨骼肌、心肌和神经组织去极化,可促进细胞膜通透性,轴突传导阻滞,以及溶解肿瘤细胞等。自从1936年Sarker从眼镜蛇(Najanajaatra)蛇毒中分离出一个能使离体猫心停搏的毒素以来,多种类似的毒素如心脏毒素、细胞毒素、骨骼肌去极化因子、眼镜蛇碱、直接溶血因子等相继被分离出来,基于这些碱性多肽都作用于细胞膜的共性,又被称为膜毒素(Membranetoxin)或膜活性多肽(Membraneactivepolypeptide),有足够的证据表明,这些物质或是…     

蛇毒L-氨基酸氧化酶抗肿瘤作用研究进展

L-氨基酸氧化酶（LAAO）广泛地存在于各种蛇毒中。近年来许多文献报道了蛇毒L-氨基酸氧化酶具有与血小板相互作用、细胞毒性及诱导细胞凋亡作用,还报道它们具有出血或溶血活性、引起水肿及抗细菌、抗艾滋病病毒的特性。本文就其抗肿瘤方面的研究进行综述,介绍蛇毒L-氨基酸氧化酶的抑瘤机制、理化性质及国内外研究现状和应用前景。     

蛇毒心脏素对荷瘤小鼠的抗肿瘤作用初步研究

目的 探讨蛇毒心脏毒素（ＣＴＸ）对荷瘤小鼠Ｓ１８０腹水瘤细胞生长抑制的影响。方法 小鼠腹腔接种Ｓ１８０活瘤细胞,连续１０ｄ分别腹腔注ＣＴＸ０．８ｍｋｇ、０．４ｍｇ／ｋｇ、０．２ｍｇ／ｋｇ,分别统计荷瘤小鼠的体重变化和癌细胞死亡率,并用有丝分裂完全民法分析体内癌细胞的有丝分裂过程,结果 ＣＴＸ各剂量组荷瘤小鼠的体重抑制和癌细胞的有丝分裂,表现在０．４ｍｇ／ｋｇ实验组腹水Ｓ１８０细胞处于有丝分裂前期和     

国内20年蛇毒与肿瘤文献分析

蛇毒是天然毒蛋白之一,其在肿瘤方面的应用已受到国内、外重视。本文就国内１９７７～１９９７年的有关文献进行调查与分析,供有关人员了解这方面的研究进展,以利于进一步开发蛇毒在肿瘤方面的应用。１材料与方法本文调查分析的文献从４种方法检索得到：（１）通过主题...     

小柴胡汤抗肿瘤作用研究进展

小柴胡汤原自<伤寒论>,由东汉著名医学家张仲景所创.其临床应用广泛,国内外学者对该方进行了大量的实验和临床研究,发现该方具有预防和治疗肿瘤的作用.笔者就近年来的研究进展,作一综述.     

蛇毒抗肿瘤组分的研究进展

介绍了近几年来蛇毒在抗肿瘤作用方面的最新研究进展。蛇毒抗肿瘤的机制主要有三种：细胞毒作用、阻断整合素及诱导细胞凋亡。本文概述了近年来从不同种蛇毒中分离获得的具有抗肿瘤活性的组分。     

蛇毒心脏毒素对荷瘤小鼠的抗肿瘤作用初步研究

目的探讨蛇毒心脏毒素（ＣＴＸ）对荷瘤小鼠Ｓ１８０腹水瘤细胞生长抑制的影响。方法小鼠腹腔接种Ｓ１８０活瘤细胞,连续１０ｄ分别腹腔注射ＣＴＸ０．８ｍｇ／ｋｇ、０．４ｍｇ／ｋｇ、０．２ｍｇ／ｋｇ,分析统计荷瘤小鼠的体重变化和癌细胞死亡率,并用有丝分裂完全阻断法分析体内癌细胞的有丝分裂过程。结果ＣＴＸ各剂量组荷瘤小鼠的体重抑制和癌细胞死亡率均有明显的剂量反应关系,与对照组相比有显著的差异（Ｐ＜０．０１）;镜检发现ＣＴＸ能抑制体内癌细胞的有丝分裂,表现在０．４ｍｇ／ｋｇ和０．８ｍｇ／ｋｇ实验组腹水Ｓ１８０细胞处于有丝分裂前期和中期的细胞数量明显减少,其ＭＩ值分别为０．７１％和０．８０％,比对照组显著减少（Ｐ＜０．００１）。结论ＣＴＸ对Ｓ１８０小鼠体内癌细胞的生长有抑制和杀伤作用,并通过干扰和阻断癌细胞的有丝分裂过程,抑制腹水的生长。     

蛇毒检测技术研究进展

介绍了放射免疫测定法,凝集测定法,免疫电泳检测,荧光免疫测定法,酶联免疫吸附测定法和生物传感器检测方法在蛇毒检测中的应用,并比较了各种方法的优点和不足。     

蛇毒血小板聚集抑制剂的研究进展

蛇毒血小板聚集抑制剂的研究进展孙林光综述管锦霞审校（广州医学院广州蛇毒研究所广州,５１０１８２）血小板是血液中最小的、具有多种功能的细胞,它在生理性止血以及血栓形成、动脉粥样硬化等病理过程中起着重要的作用［１］。蛇毒中广泛存在抑制血小板聚集的活性组分...     

蛇毒中非成瘾性止痛剂的研究进展

普通止痛药 (去痛片 )长期滥用极易成瘾 ,产生耐受性。因此 ,寻找新的无成瘾性止痛剂具有十分重要的意义。蛇毒替代吗啡用于癌症晚期的镇痛已有报道。目前 ,已有研究毒素的蛇种属主要有Vipera berus,Crotalus adamanteus,C.durissusterrificus,Bothrops alternatus,B.cotiara,B.jararacussu和 N aja naja。止痛有效的产品已从眼镜蛇毒 (Naja naja)中分离得到 ,由于它具有更高的镇痛活性 ,且无成瘾性 ,有可能成为吗啡的重要替代品。从 V.aspis和 V.ammodytes中分离得到的戒毒素在关节炎和风湿症的治疗中也取得了满意效果。另外眼镜蛇毒素…     

The venom and venom apparatus of the sea snake Lapemis hardwicki Gray

The venom apparatus of Lapemis hardwicki , consisting of two functional fangs, their venom glands, and associated musculature, are described. The yield of venom per snake ranged from 2.4-5.2 mg. The LD₅₀ of the crude venom varied from 0.7-1.4 mg/kg intravenously in mice. The toxicological, chemical and immunological properties of the venom are discussed.     

舟山眼镜蛇毒抗肿瘤有效组分分离及其抑瘤作用研究初探

目的从舟山眼镜蛇(Naja atraCantor)蛇毒(snake venom,SV)中分离得蛇毒组分,探讨SV及其分离组分的LD50和抑制肿瘤的作用。方法采用凝胶柱层析方法从蛇毒中分离得到了前Ⅰ1、Ⅰ1、Ⅱ1、Ⅱ2、Ⅲ1、Ⅲ2及Ⅳ等7种组分。采用急性毒性实验、MTT法,研究SV及其7种SV分离组分的LD50和抑制肿瘤的作用。结果 SV经Sephadex G-50层析,可分离为前Ⅰ、Ⅰ、Ⅱ、Ⅲ及Ⅳ5个组分,根据峰面积大小排列:ⅢⅡⅠⅣ前Ⅰ。5个组分再经Sephadex G-25柱层析,可获得7个脱盐组分:前Ⅰ1、Ⅰ1、Ⅱ1、Ⅱ2、Ⅲ1、Ⅲ2及Ⅳ。通过急性毒性实验,明确Ⅳ的毒性最大,其次为Ⅲ2及Ⅲ1,三者的LD50值均低于SV;而Ⅰ1、Ⅱ1、Ⅱ2的毒性均小于SV,前Ⅰ1几乎无毒。SV组分Ⅲ2和Ⅳ的抑瘤作用最强,在高浓度(20μg/ml)时对实验中的2种人肿瘤细胞的抑制率均达到60%以上。结论从SV中分离得到了前Ⅰ1、Ⅰ1、Ⅱ1、Ⅱ2、Ⅲ1、Ⅲ2以及Ⅳ7种组分;组分Ⅳ毒性最强,依次为Ⅲ2Ⅲ1SVⅡ2Ⅱ1Ⅰ1前Ⅰ1;SV及其7种分离组分对2种人肿瘤细胞株(SGC-7901、A549)的生长抑制有一定的特异性,而不同的SV分离组分对同一肿瘤细胞抑制作用亦有差异。     

Proteome analysis of snake venom toxins: pharmacological insights

Snake venoms are an extremely rich source of pharmacologically active proteins with a considerable clinical and medical potential. To date, this potential has not been fully explored, mainly because of our incomplete knowledge of the venom proteome and the pharmacological properties of its components, in particular those devoid of enzymatic activity. This review summarizes the latest achievements in the determination of snake venom proteome, based primarily on the development of new strategies and techniques. Detailed knowledge of the venom toxin composition and biological properties of the protein constituents should provide the scaffold for the design of new more effective drugs for the treatment of the hemostatic system and heart disorders, inflammation, cancer and consequences of snake bites, as well as new tools for clinical diagnostic and assays of hemostatic parameters.     

蛇毒类凝血酶的分子生物学研究进展及其应用

蛇毒类凝血酶在体外可以作用于纤维蛋白原使其凝固,具有类似凝血酶的功能。但在体内却表现出抗凝、降纤的功能。本概述了蛇毒类凝血酶对纤维蛋白原的识别和作用、序列同源性特点、cDNA克隆的表达以及在临床中的应用。     

蛇毒类激肽释放酶的研究进展

蛇毒丝氨酸蛋白酶是蛇毒中一类丰富的蛋白水解酶,具有重要的临床应用价值。其中一种丝氨酸蛋白酶一类激肽释放酶,作用于激肽原释放激肽,引起血管舒张,改善微循环,从而逐渐受到关注。对蛇毒中类激肽释放酶的分布、分离制备、生化性质、结构研究和药效研究等方面进行了综述,同时指出了目前存在的问题及今后的发展方向,以期为进一步的基础研究提供理论基础。     

Crystal structure determination of alkaline haemorrhagin AaHⅢ from snake venom of Agkistrodon acutus

The haemorrhagin AaH III isolated from the snake venom ofAgkistrodon acutus is one of the few alkaline ones in snake venoms. Its crystals belong to space group P2₁2₁2₁ witha = 9. 573 4 nm,b = 4. 996 7 nm andc = 4.728 8 nm. Its crystal structure was determined by the molecular replacement method according to the model of metalloproteinase Adamalysin II from eastern rattlesnake venom. The AaH III structure has been refined by PROLSQ. The finalR factor was 0.254 and the RMS deviations of bond lengths and angles were 0.001 8 nm and 1.5°. The structure comparison suggested that AaH III has a similar structure to other snake venom zinc-metalloproteinases. They all belong to matrix metalloproteinases super-family. Project supported by the Chinese Academy of Sciences, State Key Laboratory of Biomacromolecules and State Education Commission of China.     

The effect of post-translational modifications on the hemorrhagic activity of snake venom metalloproteinases

Metalloproteinases (MPs) are Zn(+)-dependent endoproteolytic enzymes, abundant in crotalid and viperid snake venoms. Most snake venom metalloproteinases (svMPs) are active on extracellular matrix components and this effect is thought to result in bleeding as a consequence of the basement membrane disruption in capillaries. Jararhagin and ACLH are hemorrhagic svMPs from Bothrops jararaca and Agkistrodon contortrix laticinctus venom, respectively. Both enzymes demonstrate proteolytic activity on fibrinogen and fibronectin and jararhagin inhibits collagen-induced platelet aggregation in vitro. This work describes the expression, purification and successful refolding of the recombinant ACLH zymogen (rPRO-ACLH) as well as the catalytic domain of jararhagin (rCDJARA). The heterologous proteins were produced in E. coli, an in vivo expression system that does not make post-translational modifications. The recombinant refolded proteins did not show any hemorrhagic activity in mice skin, as well as the native deglycosylated jararhagin and ACLH. However, they preserved their proteolytic activity on fibrinogen and fibronectin. It seems that the hemorrhagic properties of these hemorrhagins are dependent on post-translational modifications, whereas their proteolytic activity is not dependent on such modifications.     

Coevolution of diet and prey-specific venom activity supports the role of selection in snake venom evolution

The processes that drive the evolution of snake venom variability, particularly the role of diet, have been a topic of intense recent research interest. Here, we test whether extensive variation in venom composition in the medically important viper genus Echis is associated with shifts in diet. Examination of stomach and hindgut contents revealed extreme variation between the major clades of Echis in the proportion of arthropod prey consumed. The toxicity (median lethal dose, LD₅₀) of representative Echis venoms to a natural scorpion prey species was found to be strongly associated with the degree of arthropod feeding. Mapping the results onto a novel Echis phylogeny generated from nuclear and mitochondrial sequence data revealed two independent instances of coevolution of venom toxicity and diet. Unlike venom LD₅₀, the speed with which venoms incapacitated and killed scorpions was not associated with the degree of arthropod feeding. The prey-specific venom toxicity of arthropod-feeding Echis may thus be adaptive primarily by reducing venom expenditure. Overall, our results provide strong evidence that variation in snake venom composition results from adaptive evolution driven by natural selection for different diets, and underscores the need for a multi-faceted, integrative approach to the study of the causes of venom evolution.     

半夏和滴水珠抗五步蛇毒中毒作用的实验研究

目的研究滴水珠与半夏生药及其提取物抗五步蛇毒的作用。方法将ICR小鼠随机分为半夏生药组、半夏醇提物组、滴水珠生药组、滴水珠醇提物组、空白对照组、阳性对照组及模型组,各组小鼠均灌胃给药7天,并观察各给药组小鼠的体重变化情况;在末次给药1h后于小鼠腹腔注射五步蛇毒,观察各组小鼠的中毒表现,并统计各组小鼠的死亡率,比较各组小鼠的肝脏指数、脾脏指数及胸腺指数,并对各组小鼠血浆纤维蛋白原（FIB）、血浆凝血酶原时间（PT）、凝血酶时间（TT）、活化部分凝血酶时间（APTT）以及血小板（PLT）、红细胞（RBC）和白细胞（WBC）计数进行比较。结果半夏和滴水珠醇提物、半夏和滴水珠生药均可降低五步蛇毒中毒小鼠的死亡率,对五步蛇毒引起的小鼠PT、TT、APTT上升和FIB下降具有显著的抑制作用,与模型组相比P〈0.05;并可影响五步蛇毒中毒小鼠外周血血小板（PLT）、红细胞（RBC）和白细胞（WBC）计数,与模型组相比P〈0.05。但滴水珠和半夏生药可引起小鼠体重下降,并影响肝脏、胸腺和脾脏指数,与空白对照组相比P〈0.05。结论半夏和滴水珠醇提物及半夏和滴水珠生药均具有一定的抗五步蛇毒作用,乙醇提取能降低半夏和滴水珠的毒性。     

State of functionally essential Trp-29 in snake venom neurotoxins: A proton nuclear magnetic resonance study

Proton nuclear magnetic resonance (NMR) spectra have been recorded of various neurotoxins from snake venoms.pH dependence of the chemical shifts and resonance intensity has been followed for the functionally essential Trp-29. The indole N-1 proton of Trp-29 in -bungarotoxin, toxin B, and cobrotoxin exhibits appreciably large upfield shifts as thepH is lowered and the suppressed exchange with the solvent hydrogen atpH 3–4, but not inNaja haje annulifera 10 where Asp-31 is replaced with Gly-31. This observation strongly suggests the presence of a hydrogen bond between Trp-29 and Asp-31 that is probably important in stabilizing the arrangement of the functionally essential residues to form a distinct binding region for the receptor.