BACKGROUND Botulinum neurotoxin(BoNT)is widely recognized as an effective therapeutic agent for managing various neurological disorders,characterized by motor impairments and neuromuscular deficits.BoNT works by modul...BACKGROUND Botulinum neurotoxin(BoNT)is widely recognized as an effective therapeutic agent for managing various neurological disorders,characterized by motor impairments and neuromuscular deficits.BoNT works by modulating the release of acetylcholine at the neuromuscular junction.Recently,BoNT has been shown to enhance spatial memory and attenuate anxiety in experimental aging animals.While neurogenesis in the hippocampus contributes to cognitive properties,BoNT treatment could potentially influence the regulation of adult neurogenesis.As aging-associated microglial activation impairs neurogenesis,the anti-inflammatory properties of BoNT could be associated with the modulation of microglial activity,thereby enhancing cognitive function.AIM To investigate the neurogenic and microglial modulatory properties of BoNT in the hippocampus of aging experimental mice.METHODS Experimental aging mice were administered BoNT and after four weeks,the animals were sacrificed.The brains were subjected to cryosections followed by immunohistochemical analysis to quantify doublecortin(DCX)-positive immature neurons,bromodeoxyuridine(BrdU)-neuronal nuclei(NeuN)double positive newly matured neurons and ionized calcium-binding adapter molecule 1(Iba1)-positive microglia in the hippocampal dentate gyrus.In parallel,an additional set of animals was used to evaluate BoNT-mediated alterations in key inflammatory markers such as cyclooxygenase(COX)-2,and nitric oxide(NO)in hippocampal tissues.RESULTS The results revealed a significant increase in the number of DCX-positive immature neurons and BrdU-NeuN positive differentiated neurons in the hippocampus of the BoNT-treated group compared to the control.This enhancement in neurogenesis was accompanied by a marked reduction in the activated form of microglial cells,coupled with decreased mRNA expression of COX-2 and reduced NO levels in the hippocampus of BoNT-treated animals.CONCLUSION This study validates the proneurogenic and anti-neuroinflammatory properties of BoNT,which may underlie its procognitive effects.Hence,BoNT could be a promising therapeutic agent for treating various neurocognitive disorders.展开更多
The present study was designed to examine the therapeutic effects of Botulinum neurotoxin A(BoNT/A)on depression-like behaviors in mice and to explore the potential mechanisms.These results revealed that a single faci...The present study was designed to examine the therapeutic effects of Botulinum neurotoxin A(BoNT/A)on depression-like behaviors in mice and to explore the potential mechanisms.These results revealed that a single facial injection of BoNT/A induced a rapid and prolonged improvement of depression-like behaviors in naive and space-restriction-stressed(SRS)mice,reflected by a decreased duration of immobility in behavioral despair tests.BoNT/A significantly increased the 5-hydroxytryptamine(5-HT)levels in several brain regions,including the hippocampus and hypothalamus,in SRS mice.BoNT/A increased the expression of the N-methyl-Daspartate receptor subunits NR1 and NR2 B in the hippocampus,which were significantly decreased in SRS mice.Furthermore,BoNT/A significantly increased the expression of brain-derived neurotrophic factor(BDNF)in the hippocampus,hypothalamus,prefrontal cortex,and amygdala,which were decreased in SRS mice.Finally,BoNT/A transiently increased the levels of phosphorylated extracellular signal-regulated kinase(p-ERK)and cAMPresponse element binding protein(p-CREB),which were suppressed in the hippocampus of SRS mice.Collectively,these results demonstrated that BoNT/A treatment has antidepressant-like activity in mice,and this is associated with increased 5-HT levels and the activation of BDNF/ERK/CREB pathways in the hippocampus,supporting further investigation of BoNT/A therapy in depression.展开更多
A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sat...A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sativus were treated with 1-fluoro-2,4-dinitrobenzene (FDNB) and a reversed-phase high-performance liquid chromatographic method for the separation of the derivatives in the pmol range is reported.展开更多
A loop modeling method, adaptive simulated annealing, for ab initio prediction of protein loop structures, as an optimization problem of searching the global minimum of a given energy function, is proposed. An interfa...A loop modeling method, adaptive simulated annealing, for ab initio prediction of protein loop structures, as an optimization problem of searching the global minimum of a given energy function, is proposed. An interface-friendly toolbox—LoopModeller in Windows and Linux systems, VC++ and OpenGL environments is developed for analysis and visualization. Simulation results of three short-chain neurotoxins modeled by LoopModeller show that the method proposed is fast and efficient.展开更多
Objective: To describe the latest progress in the use of botulinum neurotoxin for post-stroke limb spasm. Methods: This paper looks up the relevant research literatures in recent years in PubMed, Web of Science, Sprin...Objective: To describe the latest progress in the use of botulinum neurotoxin for post-stroke limb spasm. Methods: This paper looks up the relevant research literatures in recent years in PubMed, Web of Science, Springer, Ovid, CNKI, WanFang databases and summarizes them. Results: The latest progress in the use of botulinum neurotoxin for post-stroke limb spasm was studied from the following aspects: the action mechanism of botulinum neurotoxin;efficacy evaluation;injection dose;target muscle selection;guiding technology;combination therapy. Conclusion: Botulinum neurotoxin is the first-line treatment for post-stroke limb spasm. We need to make continuous improvement and progress from the treatment period, injection dose, target muscle selection, guiding technology and efficacy evaluation to improve the quality of life of the majority of post-stroke survivors in China.展开更多
During evolution, scorpions have developed the ability to produce a series of toxins. Scorpion toxins, which are reserved in terminal segments of scorpion, serve as the arms for predation and self-defence. They have a...During evolution, scorpions have developed the ability to produce a series of toxins. Scorpion toxins, which are reserved in terminal segments of scorpion, serve as the arms for predation and self-defence. They have also been used as medicine for some human sickness. As far as the targets that they act on are concerned, these toxins can be展开更多
Suitable pattern and high yield were obtained when the reverse-phase performance liquidchromatography (RP-HPLC) was used to separate neurotoxins from venom of Chinese scorpion Buthusmartensi Karsch.Using this techniqu...Suitable pattern and high yield were obtained when the reverse-phase performance liquidchromatography (RP-HPLC) was used to separate neurotoxins from venom of Chinese scorpion Buthusmartensi Karsch.Using this technique,the venom was first separated to two main regions.The toxicitytests show that the insect-selective neurotoxical components are concentrated in the latter region,from whichfive insect-selective neurotoxins designated by BmK IT1-IT5 were obtained.According to the results of thetoxicity test as well as the amino acid composition and N-terminal analyses,BmK IT1 is the excitatory insectneurotoxin as reported in a previous paper,and the others are the newly found depressant insect-selectiveneurotoxins.The molecules of all the four toxins are single-chain minipeptides of about 60 amino acids.Their isoelectric points (pI) are between 8.3 and 8.5.The fact that BmK IT2 loses completely its insect tox-icity after being modified by fluorochrome shows that the positive charges on the molecular surface of thiskind of toxins are important to maintaining the bioactivity of the molecules.展开更多
Diverse subtypes of voltage-gated sodium channels(VGSCs)have been found throughout tissues of the brain,muscles and the heart.Neurotoxins extracted from the venom of the Asian scorpion Buthus martensi Karsch(BmK)act a...Diverse subtypes of voltage-gated sodium channels(VGSCs)have been found throughout tissues of the brain,muscles and the heart.Neurotoxins extracted from the venom of the Asian scorpion Buthus martensi Karsch(BmK)act as sodium channel-specific modulators and have therefore been widely used to study VGSCs.α-type neurotoxins,named BmK I,BmKαIV and BmK abT,bind to receptor site-3 on VGSCs and can strongly prolong the inactivation phase of VGSCs.In contrast,β-type neurotoxins,named BmK AS,BmK AS-1,BmK IT and BmK IT2,occupy receptor site-4 on VGSCs and can suppress peak currents and hyperpolarize the activation kinetics of sodium channels.Accumulating evidence from binding assays of scorpion neurotoxins on VGSCs,however,indicate that pharmacological sensitivity of VGSC subtypes to different modulators is much more complex than that suggested by the simpleα-type and β-type neurotoxin distinction.Exploring the mechanisms of possible dynamic interactions between site 3-/4-specific modulators and region-and/or speciesspecific subtypes of VGSCs would therefore greatly expand our understanding of the physiological and pharmacological properties of diverse VGSCs.In this review,we discuss the pharmacological and structural diversity of VGSCs as revealed by studies exploring the binding properties and cross-competitive binding of site 3-or site 4-specific modulators in VGSC subtypes in synaptosomes from distinct tissues of diverse species.展开更多
Botulinum neurotoxins serotype A(BoNT/A)is the deadliest toxins known to humans and the"Category A"agent for bioterrorism.Over the past 20 years,significant efforts have been put forth to develop effective i...Botulinum neurotoxins serotype A(BoNT/A)is the deadliest toxins known to humans and the"Category A"agent for bioterrorism.Over the past 20 years,significant efforts have been put forth to develop effective inhibitors of BoNT/A.Unfortunately,few identified inhibitors possess noteworthy efficacy against BoNT/A in vivo.Here,we performed a high-throughput virtual screening based on the structure-based docking simulations and found a novel potent scaffold 2-thionicotinate that inhibits the BoNT/A light chain(LC).We then synthesized and optimized a novel series of 2-thionicotinate derivatives and comprehensively evaluated their activity against BoNT/A in vitro and in vivo.An optimized compound ZM299 effectively exhibits anti-BoNT/A activity in primary neurons and displayed remarkably therapeutic efficacy against BoNT/A in vivo,which could raise the survival rate of intoxicated mice to 100%(12/12)after lethal doses of BoNT/A exposures.These findings demonstrate that 2-thionicotinates is a promising scaffold for producing more effective anti-BoNT/A analogs,and compound ZM299 is worthy of further preclinical evaluation as a drug candidate for the treatment of botulism.展开更多
Considering the factors which affect gene transcription, translation and the stability of mRNA, without changing the amino acid composition of the encoded polypeptide, AaIT gene encoding insect-specific neurotoxin was...Considering the factors which affect gene transcription, translation and the stability of mRNA, without changing the amino acid composition of the encoded polypeptide, AaIT gene encoding insect-specific neurotoxin was designed and synthesized according to bias in codon choice, overall G+C content and G + C content of bases at the third position in codons of polyhedrin genes of baculovirus and of plant genes as well. AaIT gene was fused behind a synthetic gp67 signal sequence and then recombined into the genome of Trichoplusia ni nuclear polyhedrosis virus (TnNPV) by transfer vector pSXIV VI+X3. The recombinant virus TnNPV-AalT (occ+-gal-) was screened. The results of Southern blotting and SDS-PAGE demonstrated that AaIT gene had integrated into the genome of virus and expressed. Bioassays on the 3rd-instar Trichoplusia ni larvae showed that recombinant viruses TnNPV-AalT could shorten the time of killing insect and improve the efficiency of killing agronomically important insects.展开更多
Scorpion anti-insect toxins can be divided into long chain (about 61-70 aminoacid residues)and short chain (about 5 amino acid residues) types according to theirmolecular size, and the former can be further divided in...Scorpion anti-insect toxins can be divided into long chain (about 61-70 aminoacid residues)and short chain (about 5 amino acid residues) types according to theirmolecular size, and the former can be further divided into excitatory and depressanttypes on the basis of their pharmacological action. In our previous papers, the iso-lation and determination of the primary structure of an excitatory展开更多
Scorpion toxins are a family of small neurotoxic proteins with high selectivity. Gener-ally, most of the toxins are a group of basic homologous polypeptides containing about60—80 amino acids except BmK Ⅳ whose pl is...Scorpion toxins are a family of small neurotoxic proteins with high selectivity. Gener-ally, most of the toxins are a group of basic homologous polypeptides containing about60—80 amino acids except BmK Ⅳ whose pl is 5.3. It has been reported that theybind to various ion channels with high affinity and selectivity. In spite of the significantsequence similarity found among different toxins, they display various degrees of toxicityand specificity to different animal species. So far they form a good system to study thestructure-function relationship.展开更多
The crystal structure of an acidic neurotoxin, BmK M8, from Chinese scorpion Buthus martensii Karsch was determined at 0.25 nm resolution. The X-ray diffraction data of BmK M8 crystals at 0.25nm resolution were collec...The crystal structure of an acidic neurotoxin, BmK M8, from Chinese scorpion Buthus martensii Karsch was determined at 0.25 nm resolution. The X-ray diffraction data of BmK M8 crystals at 0.25nm resolution were collected on a Siemens area detector. Using molecular replacement method with a basic scorpion toxin AaH II in a search model, the cross-rotation function, PC-refinement and translation function were calculated by X-PLOR program package. The correct orientation and position of BmK M8 molecule in crystal were determined in a resolution range of 1.5 - 0.35nm, The oystallographic refinement was further performed by stereo-chemical restrict least-square technique, followed by simulated annealing, slow-cooling protocols. The final crystallographic R-factor at 0.8-0.25 nm is 0.171. The standard deviations of bond length and bond angle from ideality are 0.001 7nm and 2.24° , respectively. The final model of BmK M8 structure is composed of a dense core of secondary structure elements by a stretch of α-helix with two and a half turns (residues 19-28) and a three-stranded antiparallel β-sheet (residues 2-4, 32 - 37, 45- 51). In addition, three loops protruded from the structural core. The general folding properties of BmK M8 molecule were described; a common structure motif which may appear in all scorpion neurotoxins was identified. The conserved aromatic residues and charged residues were found to be distributed on two roughly opposite surfaces of the molecule. The relationship between these two faces and receptor-binding sites are also discussed.展开更多
The many-banded krait,Bungarus multicinctus,has been recorded as the animal resource of JinQianBaiHuaShe in the Chinese Pharmacopoeia.Characterization of its venoms classified chief phyla of modern animal neurotoxins....The many-banded krait,Bungarus multicinctus,has been recorded as the animal resource of JinQianBaiHuaShe in the Chinese Pharmacopoeia.Characterization of its venoms classified chief phyla of modern animal neurotoxins.However,the evolutionary origin and diversification of its neurotoxins as well as biosynthesis of its active compounds remain largely unknown due to the lack of its high-quality genome.Here,we present the 1.58 Gbp genome of B.multicinctus assembled into 18 chromosomes with contig/scaffold N50 of 7.53 Mbp/149.8 Mbp.Major bungarotoxin-coding genes were clustered within genome by family and found to be associated with ancient local duplications.The truncation of glycosylphosphatidylinositol anchor in the 3'-terminal of a LY6E paralog released modern three-finger toxins(3FTxs)from membrane tethering before the Colubroidea divergence.Subsequent expansion and mutations diversified and recruited these 3FTxs.After the cobra/krait divergence,the modern unit-B ofβ-bungarotoxin emerged with an extra cysteine residue.A subsequent point substitution in unit-A enabled theβ-bungarotoxin covalent linkage.The B.multicinctus gene expression,chromatin topological organization,and histone modification characteristics were featured by transcriptome,proteome,chromatin conformation capture sequencing,and ChIP-seq.The results highlighted that venom production was under a sophisticated regulation.Our findings provide new insights into snake neurotoxin research,meanwhile will facilitate antivenom development,toxin-driven drug discovery and the quality control of JinQianBaiHuaShe.展开更多
Phospholipase A<sub>2</sub> catalyzes specially the hydrolysis of the ester bond at the C<sub>2</sub> position of3-sn-phosphoglycerides. Besides the enzymatic activity, the venom phospholipase ...Phospholipase A<sub>2</sub> catalyzes specially the hydrolysis of the ester bond at the C<sub>2</sub> position of3-sn-phosphoglycerides. Besides the enzymatic activity, the venom phospholipase A<sub>2</sub> from varioussources displays complicated pharmacological activity and toxicity. The phospholipaseA<sub>2</sub> neurotoxin is a noteworthy group in all phospholipase A<sub>2</sub> species. It has been展开更多
Scorpion venoms contain several kinds of neurotoxins, such as antimammalian neurotoxins, anti-insect neurotoxins and others. But most of them form a family of structurally related single chain proteins of 60—70 amino...Scorpion venoms contain several kinds of neurotoxins, such as antimammalian neurotoxins, anti-insect neurotoxins and others. But most of them form a family of structurally related single chain proteins of 60—70 amino acid residues and selectively interact with voltage-dependent sodium channels in different excitable cells, only a few minipeptides of 31—39 amino acid residues are proved to block potassium channels. As a kind of molecular probe, scorpion neurotoxins have been widely used for analyzing the展开更多
BmK M4 is a neutral neurotoxin in the BmK toxin series. It is medially toxic and belongs to group III cc-toxins. The purified sample was crystallized in rhombic space group P6 Using an X-ray diffraction technique, the...BmK M4 is a neutral neurotoxin in the BmK toxin series. It is medially toxic and belongs to group III cc-toxins. The purified sample was crystallized in rhombic space group P6 Using an X-ray diffraction technique, the crystal structure of BmK M4 was revealed by molecular replacement at 0.20 nm resolution. The model was refined. The final crystallographic R factor was 0.142 and the free R factor was 0.173. The root mean square deviation is 0.001 5 nm for the bond length and 1.753° for the bond angles. 64 water molecules were added to the asymmetric unit. The refined structure showed an unusual non-prolyl cis peptide bond at residue 10. The structure was compared with group II a-toxin BmK M8 (an acidic, weak toxin). The potential structural implications of the cis peptide bond were discussed.展开更多
A natural scorpion toxin BmK 16 was purified for the first time from the venom of the Chinese scorpion Buthus martensii Karsch (BmK) by using combined gel filtration, ion exchange and reversed phase chromatograph...A natural scorpion toxin BmK 16 was purified for the first time from the venom of the Chinese scorpion Buthus martensii Karsch (BmK) by using combined gel filtration, ion exchange and reversed phase chromatography. The sequence of the N terminal 8 amino acid residues was determined by Edman degradation. Using the N terminal sequence as a tag, the database searching revealed a hit in the scorpion cDNA Bank. The sequence for N terminal 8 amino acid residues, molecular weight and amino acid compositions of BmK 16 were identical with the calculated values according to the first 64 residues' sequence of the precursor peptide alpha neurotoxin TX16 derived from the sequence of the cDNA AF156597 (EMBL). The sequence specific resonance assignment of BmK 16 was achieved and the intact sequence of BmK 16 was determined as followings: VRDAY IAKPH NCVYE CARNE YCNDL CTKNG AKSGY CQWVG KYGNG CWCKE LPDNV PIRVP GKCH. Furthermore, the results from the sequence homology analysis and the toxicity assays indicated that BmK 16 was an α like scorpion neurotoxin.展开更多
Objective:To explore the neurotoxic agent tetramine and characterized with cytotoxicity studies from the chief constituents of sea food Trochus radiatus(T.radiatus)and Thais rudolphi(T.rudolphi)for coastal people of I...Objective:To explore the neurotoxic agent tetramine and characterized with cytotoxicity studies from the chief constituents of sea food Trochus radiatus(T.radiatus)and Thais rudolphi(T.rudolphi)for coastal people of India.Methods:Extraction was performed by following the method of Hashizume et al.(1987)with apposite modification.The extracted aqueous layer was chromatographed on a column of diethylaminoethyl-Sephadex and Sephadex LH-20.To analysis the toxic compound of T.radiatus and T.rudolphi has been done by high performance thin layer chromatography,gas chromatography-mass spectrometer,and the spectral data was examined by Fourier transform infrared spectrum spectroscopy.The cytotoxicity studies of the purified samples were assessed by hemolytic assay,brine shrimp assay and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide–cell proliferation assay.Results:The tetramine content was estimated as 0.4μg/g and 1.2μg/g respectively(w/w).The maximum haemolytic activity in T.rudolphi was found to be 256 haemolytic unit and 16 haemolytic unit in T.radiatus against human erythrocytes when compared to chicken erythrocytes.The samples exhibited lethality against brine shrimps at 60 and 7μg/100 mL,respectively.The tetramine from T.rudolphi and T.radiatus showed 54.2%and 70.8%of cytotoxicity against human lymphocyte at 2 mg/ml concentration.Further in the cell morphology studies,cell showed condensed chromatin,cytoplasmic blubbing and detachment from the surface.Furthermore,the presence of tetramine was confirmed based on the R_(f) values and it was chemically identified as Tetramethylammonium chloride(Pub Chem CID:6379)through the gas chromatography-mass spectrometer analysis.Conclusions:From the human health point of view,though the residue levels of N,N,N'-trimethyl-1,2-ethanediamine,Tetramethylammonium chloride and N,N-dimethylglycine detected in this study are well below the maximum residue limits of consuming level,the continuous intake may probably have side effects at the later stage.The field of marine gastropods toxin-ology is still in its infancy but the potential yields should attract more interest in the coming years and this report has been a significant development in the stoppage;control and even suppression of human hazards.展开更多
An Buthus martensii Karsch Insect Toxin (BmK IT ) gene was inserted into the genome of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) to construct a recombinant baculovirus, AcMNPV-BmK IT. The expres...An Buthus martensii Karsch Insect Toxin (BmK IT ) gene was inserted into the genome of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) to construct a recombinant baculovirus, AcMNPV-BmK IT. The expression of BmK IT was confirmed using RT-PCR, dot blot and SDS-PAGE analysis. Dose-lethal time responses to Spodoptera exigua larvae were compared between wild-type baculovirus AcMNPV and recombinant virus AcMNPV-BmK IT. At the concentration of 1×107 PIBs/mL, the median lethal time of recombinant baculovirus (LT50 = 73.6h) on third instar S. exigua larvae showed an improvement of 13.2% over the efficacy of wild type virus (LT50 = 84.8h) during a 192h in-fection.展开更多
基金Supported by the Science and Engineering Research Board(SERB),No.SERB-EEQ/2016/000639RUSA 2.0,Biological Sciences,Bharathidasan University,No.TN RUSA:311/RUSA(2.0)/2018 dt.December 2,2020+1 种基金the University Grants Commission,Faculty Recharge Programme(UGC-FRP),New Delhi,IndiaCouncil of Scientific and Industrial Research-Senior Research Fellowship(CSIRSRF)-Direct,No.09/0475(23353)/2025-EMR-I.
文摘BACKGROUND Botulinum neurotoxin(BoNT)is widely recognized as an effective therapeutic agent for managing various neurological disorders,characterized by motor impairments and neuromuscular deficits.BoNT works by modulating the release of acetylcholine at the neuromuscular junction.Recently,BoNT has been shown to enhance spatial memory and attenuate anxiety in experimental aging animals.While neurogenesis in the hippocampus contributes to cognitive properties,BoNT treatment could potentially influence the regulation of adult neurogenesis.As aging-associated microglial activation impairs neurogenesis,the anti-inflammatory properties of BoNT could be associated with the modulation of microglial activity,thereby enhancing cognitive function.AIM To investigate the neurogenic and microglial modulatory properties of BoNT in the hippocampus of aging experimental mice.METHODS Experimental aging mice were administered BoNT and after four weeks,the animals were sacrificed.The brains were subjected to cryosections followed by immunohistochemical analysis to quantify doublecortin(DCX)-positive immature neurons,bromodeoxyuridine(BrdU)-neuronal nuclei(NeuN)double positive newly matured neurons and ionized calcium-binding adapter molecule 1(Iba1)-positive microglia in the hippocampal dentate gyrus.In parallel,an additional set of animals was used to evaluate BoNT-mediated alterations in key inflammatory markers such as cyclooxygenase(COX)-2,and nitric oxide(NO)in hippocampal tissues.RESULTS The results revealed a significant increase in the number of DCX-positive immature neurons and BrdU-NeuN positive differentiated neurons in the hippocampus of the BoNT-treated group compared to the control.This enhancement in neurogenesis was accompanied by a marked reduction in the activated form of microglial cells,coupled with decreased mRNA expression of COX-2 and reduced NO levels in the hippocampus of BoNT-treated animals.CONCLUSION This study validates the proneurogenic and anti-neuroinflammatory properties of BoNT,which may underlie its procognitive effects.Hence,BoNT could be a promising therapeutic agent for treating various neurocognitive disorders.
基金supported by grants from the National Natural Science Foundation of China (81870874, 31371179, 81300968, and 81671270)the Natural Science Foundation of Jiangsu Province, China (BK20170004, 2015-JY-029, and BK20140372)+4 种基金Jiangsu Key Laboratory of Neuropsychiatric Diseases (BM2013003)the Second Affiliated Hospital of Soochow University Preponderant Clinic Discipline Group Project Funding (XKQ2015002)the Postgraduate Research and Practice Innovation Program of Jiangsu Province, China (KYCX17-2000)Suzhou Science and Technology For People’s Livelihood (SYS201706)the Postgraduate Research and Practice Innovation Program of Jiangsu Province, China (KYCX17_2034)
文摘The present study was designed to examine the therapeutic effects of Botulinum neurotoxin A(BoNT/A)on depression-like behaviors in mice and to explore the potential mechanisms.These results revealed that a single facial injection of BoNT/A induced a rapid and prolonged improvement of depression-like behaviors in naive and space-restriction-stressed(SRS)mice,reflected by a decreased duration of immobility in behavioral despair tests.BoNT/A significantly increased the 5-hydroxytryptamine(5-HT)levels in several brain regions,including the hippocampus and hypothalamus,in SRS mice.BoNT/A increased the expression of the N-methyl-Daspartate receptor subunits NR1 and NR2 B in the hippocampus,which were significantly decreased in SRS mice.Furthermore,BoNT/A significantly increased the expression of brain-derived neurotrophic factor(BDNF)in the hippocampus,hypothalamus,prefrontal cortex,and amygdala,which were decreased in SRS mice.Finally,BoNT/A transiently increased the levels of phosphorylated extracellular signal-regulated kinase(p-ERK)and cAMPresponse element binding protein(p-CREB),which were suppressed in the hippocampus of SRS mice.Collectively,these results demonstrated that BoNT/A treatment has antidepressant-like activity in mice,and this is associated with increased 5-HT levels and the activation of BDNF/ERK/CREB pathways in the hippocampus,supporting further investigation of BoNT/A therapy in depression.
基金Tshe prOject!(39770469) supported by the National Natural Science Foundation of China.
文摘A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sativus were treated with 1-fluoro-2,4-dinitrobenzene (FDNB) and a reversed-phase high-performance liquid chromatographic method for the separation of the derivatives in the pmol range is reported.
文摘A loop modeling method, adaptive simulated annealing, for ab initio prediction of protein loop structures, as an optimization problem of searching the global minimum of a given energy function, is proposed. An interface-friendly toolbox—LoopModeller in Windows and Linux systems, VC++ and OpenGL environments is developed for analysis and visualization. Simulation results of three short-chain neurotoxins modeled by LoopModeller show that the method proposed is fast and efficient.
文摘Objective: To describe the latest progress in the use of botulinum neurotoxin for post-stroke limb spasm. Methods: This paper looks up the relevant research literatures in recent years in PubMed, Web of Science, Springer, Ovid, CNKI, WanFang databases and summarizes them. Results: The latest progress in the use of botulinum neurotoxin for post-stroke limb spasm was studied from the following aspects: the action mechanism of botulinum neurotoxin;efficacy evaluation;injection dose;target muscle selection;guiding technology;combination therapy. Conclusion: Botulinum neurotoxin is the first-line treatment for post-stroke limb spasm. We need to make continuous improvement and progress from the treatment period, injection dose, target muscle selection, guiding technology and efficacy evaluation to improve the quality of life of the majority of post-stroke survivors in China.
基金The sequences have been deposited in EMBL Bank with Accession Nos. X92077 & X92846.
文摘During evolution, scorpions have developed the ability to produce a series of toxins. Scorpion toxins, which are reserved in terminal segments of scorpion, serve as the arms for predation and self-defence. They have also been used as medicine for some human sickness. As far as the targets that they act on are concerned, these toxins can be
基金Project supported by a grant from Youth Foundation (388008) to Ji Yong-hua from the National Natural Science Foundation of China and the grant-in-aid for overseas scientific research from the Ministry of Education,Science and Culture,Japan.
文摘Suitable pattern and high yield were obtained when the reverse-phase performance liquidchromatography (RP-HPLC) was used to separate neurotoxins from venom of Chinese scorpion Buthusmartensi Karsch.Using this technique,the venom was first separated to two main regions.The toxicitytests show that the insect-selective neurotoxical components are concentrated in the latter region,from whichfive insect-selective neurotoxins designated by BmK IT1-IT5 were obtained.According to the results of thetoxicity test as well as the amino acid composition and N-terminal analyses,BmK IT1 is the excitatory insectneurotoxin as reported in a previous paper,and the others are the newly found depressant insect-selectiveneurotoxins.The molecules of all the four toxins are single-chain minipeptides of about 60 amino acids.Their isoelectric points (pI) are between 8.3 and 8.5.The fact that BmK IT2 loses completely its insect tox-icity after being modified by fluorochrome shows that the positive charges on the molecular surface of thiskind of toxins are important to maintaining the bioactivity of the molecules.
基金supported by the National Basic Research Program of China(Grant Nos.1999054001,2006CB500801,and 2010CB529806)partially by grants from Key discipline“Molecular Physiology”of Shanghai Education Committee.
文摘Diverse subtypes of voltage-gated sodium channels(VGSCs)have been found throughout tissues of the brain,muscles and the heart.Neurotoxins extracted from the venom of the Asian scorpion Buthus martensi Karsch(BmK)act as sodium channel-specific modulators and have therefore been widely used to study VGSCs.α-type neurotoxins,named BmK I,BmKαIV and BmK abT,bind to receptor site-3 on VGSCs and can strongly prolong the inactivation phase of VGSCs.In contrast,β-type neurotoxins,named BmK AS,BmK AS-1,BmK IT and BmK IT2,occupy receptor site-4 on VGSCs and can suppress peak currents and hyperpolarize the activation kinetics of sodium channels.Accumulating evidence from binding assays of scorpion neurotoxins on VGSCs,however,indicate that pharmacological sensitivity of VGSC subtypes to different modulators is much more complex than that suggested by the simpleα-type and β-type neurotoxin distinction.Exploring the mechanisms of possible dynamic interactions between site 3-/4-specific modulators and region-and/or speciesspecific subtypes of VGSCs would therefore greatly expand our understanding of the physiological and pharmacological properties of diverse VGSCs.In this review,we discuss the pharmacological and structural diversity of VGSCs as revealed by studies exploring the binding properties and cross-competitive binding of site 3-or site 4-specific modulators in VGSC subtypes in synaptosomes from distinct tissues of diverse species.
基金the National Natural Science Foundation of China(Nos.82173743 and U20A20136).
文摘Botulinum neurotoxins serotype A(BoNT/A)is the deadliest toxins known to humans and the"Category A"agent for bioterrorism.Over the past 20 years,significant efforts have been put forth to develop effective inhibitors of BoNT/A.Unfortunately,few identified inhibitors possess noteworthy efficacy against BoNT/A in vivo.Here,we performed a high-throughput virtual screening based on the structure-based docking simulations and found a novel potent scaffold 2-thionicotinate that inhibits the BoNT/A light chain(LC).We then synthesized and optimized a novel series of 2-thionicotinate derivatives and comprehensively evaluated their activity against BoNT/A in vitro and in vivo.An optimized compound ZM299 effectively exhibits anti-BoNT/A activity in primary neurons and displayed remarkably therapeutic efficacy against BoNT/A in vivo,which could raise the survival rate of intoxicated mice to 100%(12/12)after lethal doses of BoNT/A exposures.These findings demonstrate that 2-thionicotinates is a promising scaffold for producing more effective anti-BoNT/A analogs,and compound ZM299 is worthy of further preclinical evaluation as a drug candidate for the treatment of botulism.
文摘Considering the factors which affect gene transcription, translation and the stability of mRNA, without changing the amino acid composition of the encoded polypeptide, AaIT gene encoding insect-specific neurotoxin was designed and synthesized according to bias in codon choice, overall G+C content and G + C content of bases at the third position in codons of polyhedrin genes of baculovirus and of plant genes as well. AaIT gene was fused behind a synthetic gp67 signal sequence and then recombined into the genome of Trichoplusia ni nuclear polyhedrosis virus (TnNPV) by transfer vector pSXIV VI+X3. The recombinant virus TnNPV-AalT (occ+-gal-) was screened. The results of Southern blotting and SDS-PAGE demonstrated that AaIT gene had integrated into the genome of virus and expressed. Bioassays on the 3rd-instar Trichoplusia ni larvae showed that recombinant viruses TnNPV-AalT could shorten the time of killing insect and improve the efficiency of killing agronomically important insects.
基金National Natural Science Foundation of China and partly by the Grant-in-aid for Overseas Scientific Research from the Ministry of Education, Science and Culture, Japan.
文摘Scorpion anti-insect toxins can be divided into long chain (about 61-70 aminoacid residues)and short chain (about 5 amino acid residues) types according to theirmolecular size, and the former can be further divided into excitatory and depressanttypes on the basis of their pharmacological action. In our previous papers, the iso-lation and determination of the primary structure of an excitatory
基金Project supported by the National Natural Science Foundation of China.
文摘Scorpion toxins are a family of small neurotoxic proteins with high selectivity. Gener-ally, most of the toxins are a group of basic homologous polypeptides containing about60—80 amino acids except BmK Ⅳ whose pl is 5.3. It has been reported that theybind to various ion channels with high affinity and selectivity. In spite of the significantsequence similarity found among different toxins, they display various degrees of toxicityand specificity to different animal species. So far they form a good system to study thestructure-function relationship.
基金Project supported by the National Natural Science Foundation of China.
文摘The crystal structure of an acidic neurotoxin, BmK M8, from Chinese scorpion Buthus martensii Karsch was determined at 0.25 nm resolution. The X-ray diffraction data of BmK M8 crystals at 0.25nm resolution were collected on a Siemens area detector. Using molecular replacement method with a basic scorpion toxin AaH II in a search model, the cross-rotation function, PC-refinement and translation function were calculated by X-PLOR program package. The correct orientation and position of BmK M8 molecule in crystal were determined in a resolution range of 1.5 - 0.35nm, The oystallographic refinement was further performed by stereo-chemical restrict least-square technique, followed by simulated annealing, slow-cooling protocols. The final crystallographic R-factor at 0.8-0.25 nm is 0.171. The standard deviations of bond length and bond angle from ideality are 0.001 7nm and 2.24° , respectively. The final model of BmK M8 structure is composed of a dense core of secondary structure elements by a stretch of α-helix with two and a half turns (residues 19-28) and a three-stranded antiparallel β-sheet (residues 2-4, 32 - 37, 45- 51). In addition, three loops protruded from the structural core. The general folding properties of BmK M8 molecule were described; a common structure motif which may appear in all scorpion neurotoxins was identified. The conserved aromatic residues and charged residues were found to be distributed on two roughly opposite surfaces of the molecule. The relationship between these two faces and receptor-binding sites are also discussed.
基金the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ13-YQ-047,ZXKT22006,China)quality standard system construction for the whole industry chain of Chinese medicine from Guangdong Provincial Drug Administration of China(002009/2019KT1261/2020ZDB25)+2 种基金the National Major Science and Technology Projects(2019ZX09201005,China)the Open Research Fund of Chengdu University of Traditional Chinese Medicino state Key Laboratory scluthwestern Chinese Medicine Resources(2022ZYXK2011006,China)the National Key R&D Program of China(2019YFC1711100)。
文摘The many-banded krait,Bungarus multicinctus,has been recorded as the animal resource of JinQianBaiHuaShe in the Chinese Pharmacopoeia.Characterization of its venoms classified chief phyla of modern animal neurotoxins.However,the evolutionary origin and diversification of its neurotoxins as well as biosynthesis of its active compounds remain largely unknown due to the lack of its high-quality genome.Here,we present the 1.58 Gbp genome of B.multicinctus assembled into 18 chromosomes with contig/scaffold N50 of 7.53 Mbp/149.8 Mbp.Major bungarotoxin-coding genes were clustered within genome by family and found to be associated with ancient local duplications.The truncation of glycosylphosphatidylinositol anchor in the 3'-terminal of a LY6E paralog released modern three-finger toxins(3FTxs)from membrane tethering before the Colubroidea divergence.Subsequent expansion and mutations diversified and recruited these 3FTxs.After the cobra/krait divergence,the modern unit-B ofβ-bungarotoxin emerged with an extra cysteine residue.A subsequent point substitution in unit-A enabled theβ-bungarotoxin covalent linkage.The B.multicinctus gene expression,chromatin topological organization,and histone modification characteristics were featured by transcriptome,proteome,chromatin conformation capture sequencing,and ChIP-seq.The results highlighted that venom production was under a sophisticated regulation.Our findings provide new insights into snake neurotoxin research,meanwhile will facilitate antivenom development,toxin-driven drug discovery and the quality control of JinQianBaiHuaShe.
基金Project supported by the Chinese Academy of Science.
文摘Phospholipase A<sub>2</sub> catalyzes specially the hydrolysis of the ester bond at the C<sub>2</sub> position of3-sn-phosphoglycerides. Besides the enzymatic activity, the venom phospholipase A<sub>2</sub> from varioussources displays complicated pharmacological activity and toxicity. The phospholipaseA<sub>2</sub> neurotoxin is a noteworthy group in all phospholipase A<sub>2</sub> species. It has been
基金This Work was respectively supported in part by a grant for Youth Foundation (388008) the National Natural Science Foundation of China and the Grant-in-Aid for Overeas Scientific Reseatrch from the Ministry of Education, Science Culture, Japan
文摘Scorpion venoms contain several kinds of neurotoxins, such as antimammalian neurotoxins, anti-insect neurotoxins and others. But most of them form a family of structurally related single chain proteins of 60—70 amino acid residues and selectively interact with voltage-dependent sodium channels in different excitable cells, only a few minipeptides of 31—39 amino acid residues are proved to block potassium channels. As a kind of molecular probe, scorpion neurotoxins have been widely used for analyzing the
文摘BmK M4 is a neutral neurotoxin in the BmK toxin series. It is medially toxic and belongs to group III cc-toxins. The purified sample was crystallized in rhombic space group P6 Using an X-ray diffraction technique, the crystal structure of BmK M4 was revealed by molecular replacement at 0.20 nm resolution. The model was refined. The final crystallographic R factor was 0.142 and the free R factor was 0.173. The root mean square deviation is 0.001 5 nm for the bond length and 1.753° for the bond angles. 64 water molecules were added to the asymmetric unit. The refined structure showed an unusual non-prolyl cis peptide bond at residue 10. The structure was compared with group II a-toxin BmK M8 (an acidic, weak toxin). The potential structural implications of the cis peptide bond were discussed.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 0 13 2 0 3 0 )
文摘A natural scorpion toxin BmK 16 was purified for the first time from the venom of the Chinese scorpion Buthus martensii Karsch (BmK) by using combined gel filtration, ion exchange and reversed phase chromatography. The sequence of the N terminal 8 amino acid residues was determined by Edman degradation. Using the N terminal sequence as a tag, the database searching revealed a hit in the scorpion cDNA Bank. The sequence for N terminal 8 amino acid residues, molecular weight and amino acid compositions of BmK 16 were identical with the calculated values according to the first 64 residues' sequence of the precursor peptide alpha neurotoxin TX16 derived from the sequence of the cDNA AF156597 (EMBL). The sequence specific resonance assignment of BmK 16 was achieved and the intact sequence of BmK 16 was determined as followings: VRDAY IAKPH NCVYE CARNE YCNDL CTKNG AKSGY CQWVG KYGNG CWCKE LPDNV PIRVP GKCH. Furthermore, the results from the sequence homology analysis and the toxicity assays indicated that BmK 16 was an α like scorpion neurotoxin.
基金Supported by Ministry of Earth Sciences(MoES–G4/12319)under the“Drugs from the Sea”programme.
文摘Objective:To explore the neurotoxic agent tetramine and characterized with cytotoxicity studies from the chief constituents of sea food Trochus radiatus(T.radiatus)and Thais rudolphi(T.rudolphi)for coastal people of India.Methods:Extraction was performed by following the method of Hashizume et al.(1987)with apposite modification.The extracted aqueous layer was chromatographed on a column of diethylaminoethyl-Sephadex and Sephadex LH-20.To analysis the toxic compound of T.radiatus and T.rudolphi has been done by high performance thin layer chromatography,gas chromatography-mass spectrometer,and the spectral data was examined by Fourier transform infrared spectrum spectroscopy.The cytotoxicity studies of the purified samples were assessed by hemolytic assay,brine shrimp assay and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide–cell proliferation assay.Results:The tetramine content was estimated as 0.4μg/g and 1.2μg/g respectively(w/w).The maximum haemolytic activity in T.rudolphi was found to be 256 haemolytic unit and 16 haemolytic unit in T.radiatus against human erythrocytes when compared to chicken erythrocytes.The samples exhibited lethality against brine shrimps at 60 and 7μg/100 mL,respectively.The tetramine from T.rudolphi and T.radiatus showed 54.2%and 70.8%of cytotoxicity against human lymphocyte at 2 mg/ml concentration.Further in the cell morphology studies,cell showed condensed chromatin,cytoplasmic blubbing and detachment from the surface.Furthermore,the presence of tetramine was confirmed based on the R_(f) values and it was chemically identified as Tetramethylammonium chloride(Pub Chem CID:6379)through the gas chromatography-mass spectrometer analysis.Conclusions:From the human health point of view,though the residue levels of N,N,N'-trimethyl-1,2-ethanediamine,Tetramethylammonium chloride and N,N-dimethylglycine detected in this study are well below the maximum residue limits of consuming level,the continuous intake may probably have side effects at the later stage.The field of marine gastropods toxin-ology is still in its infancy but the potential yields should attract more interest in the coming years and this report has been a significant development in the stoppage;control and even suppression of human hazards.
基金the National Natural Science Foundation of China (Grant Nos.30670282 and 30700534)the Department of Science and Technology of Shanxi Province
文摘An Buthus martensii Karsch Insect Toxin (BmK IT ) gene was inserted into the genome of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) to construct a recombinant baculovirus, AcMNPV-BmK IT. The expression of BmK IT was confirmed using RT-PCR, dot blot and SDS-PAGE analysis. Dose-lethal time responses to Spodoptera exigua larvae were compared between wild-type baculovirus AcMNPV and recombinant virus AcMNPV-BmK IT. At the concentration of 1×107 PIBs/mL, the median lethal time of recombinant baculovirus (LT50 = 73.6h) on third instar S. exigua larvae showed an improvement of 13.2% over the efficacy of wild type virus (LT50 = 84.8h) during a 192h in-fection.
