东亚钳蝎中新分离的毒素BmTx3B抑制大鼠海马神经元延迟整流性钾电流

目的：研究从东亚钳蝎毒素中新分离的短肽BmTx3B对电压门控性钾通道的作用．方法：在酶解打散的新生大鼠海马细胞,采用全细胞电压箝位方式记录,并根据动力学特性分离二种电压依赖性钾电流．结果：BraTx3B(10-100μmol／L)选择地抑制延迟整流性钾电流(IK),不影响瞬时性快钾电流(IA)．此抑制作用是可逆的,呈现浓度依赖性,但无电压依赖性．BmTx3B对延迟整流性钾电流的稳态激活和稳态失活的动力学特性无影响．结论：蝎毒短肽BmTx3B选择地抑制海马神经元延迟整流性钾通道。     

东亚钳蝎毒素对大鼠实验性大肠癌的抑制作用

前阶段研究证实蝎毒素对体外培养大肠癌细胞有显著抑制作用.为进一步探索其对大肠癌发生发展的影响,利用盐酸二甲基肼诱发Wistar鼠大肠癌的动物模,通过分组、分阶段研究蝎毒素对大肠肿瘤发生过程和组织病理改变的作用.结果发现蝎毒素可以降低诱癌率和诱癌鼠死亡率.20周内单纯诱癌组死亡率达32.6%,蝎毒灌胃组和腹腔注射组分别为23.0%和20.51%,其中蝎毒注射组死亡率与单纯诱癌组相比有显著差异有显著差异(P<0.05).20～31周单纯诱癌组诱癌率为81.82%,蝎毒注射组为44.00%,两组差异显著(P<0.01).大肠癌核仁组成区染色结果发现单纯诱癌组AgNOR颗粒明显增加而蝎毒注射组显著减少,第核AgNOR颗粒数两组有显著差异(P<0.05).结果提示蝎毒素具有去除DMH毒性,降低实验肿瘤的发生,抑制大肠肿瘤细胞rRNA活性,直接抑杀肿瘤细胞的作用.     

东亚钳蝎毒及其成分抗癫痫肽对心脏和血管的作用

本文报告河北产东亚钳蝎(Buthus martensii Karsch)毒及用柱层析法从粗毒中纯化的抗癫痫肽对心脏、血管的作用。实验结果证明蝎毒能使麻醉免LVP、左室dp/dt升高、心率稍减慢;心得安能对抗蝎毒升高LVP和dp/dt的作用。抗癲痫肽对LVP、dp/dt、心率的影响都不明显。蝎毒使离体豚鼠心脏收缩张力增强,心率减慢,并呈现频繁的心律不齐。心得安能对抗蝎毒增强心脏收缩张力的作用,但不能消除心律不齐。抗癫痫肽使心肌收缩张力下降,心率加快,同时也引起心律不齐。蝎毒能引起兔主动脉条明显收缩,作用强度约为NE的1/5,在蝎毒作用的基础上,妥拉苏林使收缩曲线升高,心得安使曲线降低。抗癲痫肽使兔主动脉条轻微松弛。用光电容积搏动法实验,蝎毒和抗癲痫肽都能使小鼠末稍血管收缩。     

重组东亚钳蝎镇痛抗肿瘤肽对胆管癌细胞化疗的增敏作用

目的探讨重组东亚钳蝎镇痛抗肿瘤肽(rAGAP)对胆管癌细胞化疗的增敏作用及其机制。方法体外培养人胆管癌细胞株HuCC-T1、QBC939和胆管上皮细胞HIBepic,单独用药:不同浓度的rAGAP、顺铂(DDP)和5-氟尿嘧啶(5-FU)处理三株细胞,四甲基偶氮唑盐比色法(MTT法)观察细胞的增殖抑制率及半抑制浓度(IC50)。联合用药:选用rAGAP(5μg/ml)、DDP(4μg/ml)、5-FU(50μg/ml)处理三株细胞,分为对照(A)组、rAGAP(B)组、DDP(C)组、rAGAP与DDP联用(D)组、5-FU(E)组、rAGAP与5-FU联用(F)组。MTT法检测细胞存活率;荧光定量PCR方法检测细胞多药耐药基因1(MDR-1)及多药耐药相关蛋白1(MRP-1)的mRNA表达。结果单独用药结果显示rAGAP抑制细胞增殖呈时间剂量依赖性,且对癌细胞具有一定的选择性;rAGAP组的IC50值明显小于DDP组和5-FU组(P<0.01)。联合用药结果显示,胆管癌细胞株HuCC-T1和QBC939中,D组较B、C组以及F组较B、E组细胞存活减少;而且MDR-1和MRP-1表达下调(P<0.01)。而在胆管上皮细胞HIBepic细胞系里,联合用药并未表现明显的增加化疗药效果的作用。结论 rAGAP可选择性抑制胆管癌细胞,与化疗药DDP和5-FU联用可增强化疗敏感性。     

芸芝多糖对黄曲霉毒素B1诱发大鼠肝癌的影响

应用小剂量AFB1饲喂大鼠诱发肝癌,以PVP为阻断剂,定期剖腹切取小块肝组织,采用光镜、电镜及组织化学(γ-GT染色)等病理检查,检测PVP对大鼠肝癌发展过程的影响。实验历时二年,结果实验Ⅰ组(AFB1 PVP同时应用)及实验Ⅱ组(AFB1 PVP先后应用)肝癌发生率(34.1％及30％)均比对照组(AFB1单独应用)低(61.3％)。肝癌前病变(γ-GT阳性灶)实验组明显低于对照组。此外肝癌发生时间实验组亦较对照组明显推迟。实验结果表明,芸芝多糖对AFB1致肝癌作用有显著抑制效果,提示它对预防肝癌有实用价值。     

不同位置注射A型肉毒毒素对除皱后额部皮肤油脂分泌及皮肤质地的影响

目的 研究不同位置注射A型肉毒毒素对除皱后额部皮肤油脂分泌及皮肤质地的影响.方法 60例额部皱纹患者,按照随机数字表法分为对照组和试验组,各30例.对照组给予A型肉毒毒素肌肉下注射治疗,试验组给予A型肉毒毒素真皮下注射治疗.比较两组患者治疗前后额部注射区域(A、B区域)皮肤油脂分泌水平、额部皮肤弹性参数R2、R5、R7...     

鞘内注射甘珀酸对腰5脊神经切断大鼠痛觉高敏的影响

目的观察鞘内注射甘珀酸(CBX)对腰5脊神经切断(SNT)大鼠机械痛阈及脊髓背角星形胶质细胞标志物(GFAP)和TNF-α、IL-1β表达的影响。方法 36只成年♂SD大鼠,随机分成3组(n=12),假手术组(Sham组)、SNT+NS组(NS组)、SNT+CBX(CBX组)。Sham组仅暴露腰5脊神经,不切断,NS组和CBX组切断腰5脊神经。术后10d,Sham组和NS组鞘内注射生理盐水10μl,CBX组鞘内注射甘珀酸5μg(10μl),分别于术前1 d,术后1、3、5、7、10 d及给药后1、2、4、6 h随机取6只大鼠测损伤侧机械痛阈(MWT),并采用免疫组化技术观察给药后2 h后损伤侧脊髓背角中GFAP表达的变化,ELISA测定损伤侧脊髓背角TNF-α和IL-1β的水平。结果 3组大鼠术前1 d,MWT差异均无显著性(P>0.05);Sham组术后各时间点与术前相比损伤侧MWT差异无显著性(P>0.05);与Sham组相比,NS组和CBX组术后1、3、5、7、10 d痛阈明显下降(P<0.05);NS组术后10 d给药后1、2、4、6 h,MWT与给药前无差异(P>0.05),但给药后2 h损伤侧脊髓背角GFAP的表达和TNF-α、IL-1β的水平较Sham组明显增高(P<0.05);CBX组给药后1、2、4 h损伤侧MWT较给药前明显提高(P<0.05),6 h无差异(P>0.05),给药后2 h损伤侧脊髓背角GFAP的表达和TNF-α、IL-1β的水平较NS组明显降低(P<0.05)。结论单次鞘内注射5μg CBX可改善脊神经切断大鼠损伤侧机械痛敏行为,该效应可能与其抑制损伤侧脊髓背角星形胶质细胞的活化,减少TNF-α、IL-1β的释放有关。     

肉毒毒素A对慢性坐骨神经结扎大鼠机械痛敏和热痛敏的影响

目的探讨肉毒毒素A(botulinum toxin type A,BoNT-A)后处理对神经病理性疼痛大鼠疼痛行为学的影响。方法建立SD大鼠右侧慢性坐骨神经结扎模型(chronic con-striction injury of sciatic nerve,CCI)。CCI术后d3始,CCI同侧肢体足底注射BoNT-A7.5、15、30U·kg-1或等容积生理盐水,或对侧肢体足底注射BoNT-A15或30U·kg-1。分别于术前、术后1、3、5、7、14d,测定大鼠的机械缩足反射阈值(MWT)和热缩足潜伏期(TWL)。结果CCI手术同侧足底皮下注射BoNT-A可以增加大鼠的MWT和TWL,对侧应用BoNT-A对MWT和TWL无影响。结论BoNT-A可以通过局部作用减轻CCI手术同侧肢体的机械痛敏和热痛敏。     

Covalent structures of BmK AS and BmK AS-1, two novel bioactive polypeptides purified from Chinese scorpion Buthus martensi Karsch.

Complete amino acid sequences of two novel bioactive polypeptides, each containing 66 amino acid residues, BmK AS and BmK AS-1 purified from the venom of Chinese scorpion Buthus martensi Karsch, have been determined by Edman sequencing and mass spectrometry on native proteins, reduced and S-carboxymethylated proteins and their peptides obtained after cleavage with proteolytic enzymes. Sequence analysis showed 86.4% structural identity between BmK AS and BmK AS-1 and also a high sequence similarity between BmK ASs and AaH IT4, a unique anti-insect toxin and a ligand of Na+ channels obtained from Sahara scorpion A. australis Hector, but poor sequence homology between BmK ASs and those of the known alpha-, beta-type and long-chain insect-selective type scorpion neurotoxins. The positions of four disulfide bridges in BmK AS-1 were established as Cys-12 and Cys-62, Cys-16 and Cys-37, Cys-23 and Cys-44, and Cys-27 and Cys-46, which are the same as those in alpha- and beta-scorpion neurotoxins. These results suggest that BmK ASs and AaH IT4 may form a new group sharing similar structural and functional properties in the family of scorpion neurotoxic polypeptides.     

Study of Anti-Inflammatory and Analgesic Activity of Scorpion Toxins DKK-SP1/2 from Scorpion Buthus martensii Karsch (BmK)

Buthus martensii Karsch (BmK), is a kind of traditional Chinese medicine, which has been used for a long history for the treatment of many diseases, such as inflammation, pain and cancer. In this study, DKK-SP1/2/3 genes were screened and extracted from the cDNA library of BmK. The DKK-SP1/2/3 were expressed by using plasmid pSYPU-1b in E. coli BL21, and recombinant proteins were obtained by column chromatography. In the xylene-induced mouse ear swelling and carrageenan-induced rat paw swelling model, DKK-SP1 exerted a significant anti-inflammatory effect by inhibiting the expression of Nav1.8 channel. Meanwhile, the release of pro-inflammatory cytokines (COX-2, IL-6) was decreased significantly and the release of anti-inflammatory cytokines (IL-10) were elevated significantly. Moreover, DKK-SP1 could significantly decrease the Nav1.8 current in acutely isolated rat DRG neurons. In the acetic acid-writhing and ION-CCI model, DKK-SP2 displayed significant analgesic activity by inhibiting the expression of the Nav1.7 channel. Moreover, DKK-SP2 could significantly inhibit the Nav1.7 current in the hNav1.7-CHO cells.     

蝎毒镇痛活性肽基因BmK AngM1的密码子优化及其真核表达分析

密码子的偏爱性是影响基因异源表达的重要因素,通过对外源基因的密码子序列进行优化可提高其表达水平。为了获得蝎毒镇痛活性肽基因BmK AngM1在毕赤酵母中的高效表达,根据毕赤酵母密码子偏爱性,将BmK AngM1基因中的毕赤酵母低利用率密码子突变为其高利用率简并密码子,克隆到表达载体pPIC9K中,转化毕赤酵母,甲醇诱导表达;重组蛋白表达量测定结果显示,优化后的BmK AngM1基因在毕赤酵母中的表达水平是优化前的3.7倍。研究结果表明,密码子优化能显著提高BmK AngM1基因在毕赤酵母中的表达水平。     

Gene cloning and sequencing of BmK AS and BmK AS-1, two novel neurotoxins from the scorpion Buthus martensi Karsch.

Based on the known amino acid sequences of BmK AS and BmK AS-1, the gene specific primers were designed and synthesized for 3' and 5' RACE (Rapid Amplification of cDNA Ends). Their partial cDNA fragments obtained by 3' and 5' RACE were cloned and sequenced, and the full length cDNA sequences of BmK AS and BmK AS-1 were then completed by overlapping their two partial cDNA sequences, respectively. The predicted amino acid sequences both consist of 85 amino acid residues including a putative signal peptide of 19 residues and a mature toxin of 66 residues. They are different in 17 amino acid residues, among them 11 residues in the mature toxin. The predicted amino acid sequences of BmK AS and BmK AS-1 were almost consistent with those determined and revised (personal communication), only different in one and two residues at their COO-terminal parts, respectively. Based on the determined cDNA sequences, and using the total DNAs isolated from the scorpion venom glands as a template, the genomic DNAs of BmK AS and BmK AS-1 were also amplified by PCR and sequenced. It showed that no intron was inserted in their open reading frames, while in the exon of signal peptide sequences of other Na+, K+ and Cl- channel toxins from the same scorpion, an intron is usually found. However, the Northern blot hybridization results indicated that the sizes of their mRNA should be around 800 bp. Their extra sequences around 400 bp which might function as an intron should be located at their 5' untranslated regions.     

不同地域东亚钳蝎蝎毒的双向电泳鉴定

摘要 目的利用蛋白质组学中双向电泳技术,定性鉴定、分析不同地域东亚钳蝎蝎毒活性的差别,探索不同产地蝎毒的蛋白质组成及功能差异。方法将不同产地的冷冻干燥蝎毒粉经溶解、除盐、浓缩后测定蝎毒蛋白质含量,进行定量的蝎毒鉴定。采用pH梯度等电聚焦和SDS PAGE凝胶电泳技术分离蝎毒蛋白质。银染后通过凝胶成像系统获得双向电泳凝胶图谱,用PD Quest图像分析软件比较分析,确定差异的特征蛋白点,从而定性鉴定不同产地蝎毒。结果获得3个样品的蛋白质指纹图谱。分别检测出80,69和77个点,特征差异蛋白点依次为56,46和55个。结论不同产地的东亚钳蝎蝎毒通过双向电泳分离蛋白后,表现出明显不同的蛋白点分布。     

Purification and pharmacological characterization of BmKK2 (alpha-KTx 14.2), a novel potassium channel-blocking peptide, from the venom of Asian scorpion Buthus martensi Karsch.

BmKK2 (alpha-KTx 14.2) is one of the novel short-chain peptides found in molecular cloning of a venom gland cDNA library from Asian scorpion Buthus martensi Karsch. Based upon its amino acid sequence, the peptide was proposed to adopt a classical alpha/beta-scaffold for alpha-KTxs. In the present study, we purified BmKK2 from the venom of B. martensi Karsch, and investigated its action on voltage-dependent K+ currents in dissociated hippocampal neurons from neonatal rats. BmKK2 (10-100 microM) selectively inhibited the delayed rectifier K+ current, but did not affect the fast transient K+ current. The inhibition of BmKK2 on the delayed rectifier K+ current was reversible and voltage-independent. The peptide did not affect the steady-state activation of the current, but caused a depolarizing shift (about 9 mV) of its steady-state inactivation curve. The results demonstrate that BmKK2 is a novel K+ channel-blocking scorpion peptide.     

Isoform-specific effects of a novel BmK 11(2) peptide toxin on Na channels.

BmK 11(2) is a 7216Da polypeptide toxin purified from the venom of the scorpion Buthus martensii Karsch. Nanomolar concentrations of the toxin prolong amphibian nerve action potentials without attenuation of the amplitude. The pharmacological action of the toxin and its sequence similarity to other alpha-scorpion toxins suggest that BmK 11(2) selectively alters voltage-gated Na channels. In order to test whether BmK 11(2) preferentially modulates the gating or kinetics of certain channel isoforms, we applied BmK 11(2) to muscle, heart and neuronal Na channels. 100nM BmK 11(2) increased the peak current amplitude of skeletal muscle (micro1) and neuronal (N1E-115) Na currents by 40 and 20%, respectively, and reduced the cardiac Na (hH1) current by 15%. The toxin slowed current decay of all isoforms, most prominently in N1E-115 (tau(BmK)/tau(Control)=12), micro1 (11), and less so for hH1 (1.3). BmK 11(2) shifted the voltage dependence of activation of micro1 and N1E-115 currents. BmK 11(2) had no effect on steady-state inactivation, use-dependent availability, and the kinetics of entry into slowly recovering inactivated states.     

Involvement of spinal nitric oxide (NO) in rat pain-related behaviors induced by the venom of scorpion Buthus martensi Karsch

In the present study, we investigated the role of spinal nitric oxide (NO) in rat pain-related behaviors induced by the venom of scorpion Buthus martensi Karsch (BmK). The results showed that the number of neuronal NO synthase (nNOS) positive neurons significantly increased in superficial (I-II), deep (V-VI) dorsal horn laminae and the ventral gray laminae (VII-X), but not in the nucleus proprius (III and IV) of bilateral L4-L5 lumbar spinal cord after unilateral intraplantar injection of BmK venom from 2h to 7d. This increase on the ipsilateral side to BmK venom injection was always greater than that on the contralateral side. Western blotting analysis confirmed that spinal nNOS expression was significantly up-regulated following BmK venom administration. In addition, intrathecal delivery of N(omega)-nitro-l-arginine methyl ester hydrochloride (l-NAME; a NOS inhibitor) before intraplantar injection of BmK venom by 10 min significantly attenuated spontaneous nociceptive responses and prevented the development of primary thermal hyperalgesia as well as bilateral mechanical hyperalgesia. Intrathecal injection of l-NAME could also partially inhibit BmK venom-induced c-Fos expression in lumbar spinal cord at 2 h. Thus, the results suggest that spinal NO as a critical mediator is involved in various pain-related behaviors and c-Fos expression induced by BmK venom in rats.     

Adrenergic and nitrergic responses of the rat isolated anococcygeus muscle to a new toxin (makatoxin I) from the venom of the scorpion Buthus martensi Karsch

1 Makatoxin I (MkTx I) is a new toxin purified from the venom of the scorpion Buthus martensi Karsch. Contractile (excitatory, adrenergic) and relaxant (inhibitory, nitrergic) responses of the rat isolated anococcygeus muscle (Acm) to MkTx I were investigated. 2 MkTx I (0.28 μm ) produced a rapid and very marked rise in the tone of the Acm which then gradually waned to the control baseline. Phentolamine (5 μm ), guanethidine (5 μm ), tetrodotoxin (2 μm ) and reserpine pretreatment in vivo (5 mg kg^?1 s.c. at 24 h and 5 mg kg^?1 i.p. at 3 h) completely blocked the contractile responses of the Acm to MkTx I. The responses to noradrenaline (NA) were blocked by phentolamine, but were potentiated by guanethidine. 3 MkTx I (0.28 μm ) also marked and rapidly relaxed the tone of the carbachol (CCh; 3 μm ), precontracted Acm. The addition of sodium nitroprusside (SNP; 1 μm ) also produced a marked and rapid relaxation of the Acm. TTx (2 μm ) or N^G-nitro-L -arginine methylester (L -NAME, 50 μm ) markedly inhibited the relaxant responses of the Acm to field stimulation (FS) as well as to MkTx I, but not the responses to SNP. 4 Therefore, the contractile responses of the rat anococcygeus muscle to MkTx I can be attributed to the release of transmitter NA acting on postjunctional α-adrenoceptors, whereas the relaxant responses of the Acm to MkTx I involve the release of nitric oxide as the neurotransmitter which, presumably, results in the activation of the enzyme guanylate cyclase leading to relaxation of the muscle.