Huwentoxin-I (HwTx-I) isaneurotoxinthatwasoriginallyisolatedfromthevenomoftheChinesebirdspiderOrnithoctonushuwena.Huwentoxin-Iisknowntobeaninhibitorof tetrodotoxin-sensitivevoltage-gatedsodiumchannels(TTX-S) (IC50 ~50nM)and N-typevoltage-sensitivecalciumchannels (IC50 ~100nM)inmammalianDRG,hippocampusandinsect’sDUMneurons.IthasonlyaveryweakeffectonL-typecalciumchannels,noeffectonTTX-Rchannelsandhasvirtuallynoeffectonmusclesodiumchannels. Theselectivity of Huwentoxin-I forcalciumchannelsappearstobehigherthan ω-conotoxinMVIIA andequivalentto ω-conotoxinGVIA. Huwentoxin-I demonstratedanantinociceptiveeffectintheratmodeloftheformalintestwhenadmiNISTratedintrathecally(ED50 ~0.28µg/kg),withoutsideeffectsoftheonesledby ω-conotoxinMVIIA.
Description:
AAsequence: Ala-Cys2-Lys-Gly-Val-Phe-Asp-Ala-Cys9-Thr-Pro-Gly-Lys-Asn-Glu-Cys16-Cys17-Pro-Asn-Arg-Val-Cys22-Ser-Asp-Lys-His-Lys-Trp-Cys26-Lys-Trp-Lys-Leu-OH
Disulfidebonds: Cys2-Cys17,Cys9-Cys22 andCys16-Cys29
Length(aa): 33
Formula: C161H246N48O44S6
MolecularWeight: 3751.77Da
Appearance:Whitelyophilizedsolid
Solubility: waterandsalinebuffer
CASnumber:
Source: Synthetic
Purityrate: >97%
Reference:
Theeffectsofhuwentoxin-Ionthevoltage-gatedsodiumchannelsofrathippocampalandcockroachdorsalunpairedmedianneurons
Huwentoxin-I(HWTX-I)isa33-residuepeptideisolatedfromthevenomofOrnithoctonushuwenaandcouldinhibitTTX-sensitivevoltage-gatedsodiumchannelsandN-typecalciumchannelsinmammaliandorsalrootganglion(DRG)neurons.However,theeffectsofHWTX-Ionmammaliancentralneuronalandinsectsodiumchannelsubtypesremainunknown.Inthisstudy,wefoundthatHWTX-Ipotentlyinhibitedsodiumchannelsinrathippocampalandcockroachdorsalunpairedmedian(DUM)neuronswiththeIC(50)valuesof66.1±5.2and4.80±0.58nM,respectively.TakentogetherwithourpreviousworkonDRGneurons(IC(50)≈55nM),theorderofsodiumchannelsensitivitytoHWTX-IinhibitionwasinsectcentralDUM≫mammalianperipheral>mammaliancentralneurons.HWTX-Iexhibitednoeffectonthesteady-stateactivationandinactivationofsodiumchannelsinrathippocampalandcockroachDUMneurons.
WangM, etal.(2012)Theeffectsofhuwentoxin-Ionthevoltage-gatedsodiumchannelsofrathippocampalandcockroachdorsalunpairedmedianneurons. Peptides. PMID: 22094230
TheantinociceptiveefficacyofHWTX-Iepidurallyadministeredinrheumatoidarthritisrats
Rheumatoidarthritis(RA)isoneoftheinflammatorykindsofarthritisintheclinicalsituation,andcytosolicCa2+overloadhasbeenproposedasoneoftheprimaryfactorsformanyinflammatorycellsactivation,whichleadtorelativeenzymesandinflammatoryfactorsrelease.ItisthereforeacceptedthatCa2+channelblockerscanprotectjointinjuryfrominflammation.InthepresentstudyweinvestigatedthepossIBLemolecularmechanismoftheantinociceptiveefficacyofHWTX-I,aspiderpeptidetoxinblockingCa2+channels,ontheratrheumatoidarthritismodel.OurstudydemonstratesthatHWTX-Icanrelievepainintheinflammatoryjointsandeliminatearthroceletosomedegree.Moreover,HWTX-Icanalsodecreasetheconcentrationoftumournecrosisfactorα(TNF-α)andincreasetheconcentrationofinterleukin4(IL-4)andinterleukin10(IL-10)inrat’sserum.HWTX-IcanalsodecreasethemRNAexpressionlevelofrelatedfactorsofTNF-α,interleukin1β(IL-1β)andinterleukin6(IL-6)ininflammatorypathwaysinrheumatoidarthritis.Therefore,thepresentresultsshowthattheepiduraladministrationofHWTX-Iiseffectiveinantinociceptionintheratmodelofrheumatoidarthritis,whichmayactthroughitsinhibitiononcertaininflammatorypathways.
WenTaoZ, etal.(2011)TheantinociceptiveefficacyofHWTX-Iepidurallyadministeredinrheumatoidarthritisrats. IntJSportsMed. PMID: 22052031
Thecrosschannelactivitiesofspiderneurotoxinhuwentoxin-Ionratdorsalrootganglionneurons
Inthispaper,weinvestigatedtheactionof huwentoxin-I (HWTX-I)purifiedfromthevenomoftheChinesebird spider OrnithoctonushuwenaonCa(2+),Na(+)channelsofadult rat dorsal root ganglion (DRG) neurons.Theresultsshowedthat huwentoxin-I couldreducethepeakcurrentsofN-typeCa(2+)channels(IC(50)approximately100nM)andTTX-SNa(+)channels(IC(50)approximately55nM),whereasnoeffectwasdetectedonTTX-RNa(+)channels.ThecomparativestudiesindicatedthattheselectivityofHWTX-IonCa(2+)channelswashigherthatofMVIIAandapproximatelythesameasthatofGVIA.HWTX-Iisthefirstdiscoveredtoxinwiththe cross channel activities fromthe spider O.huwenavenomsimilartomicroO-conotoxinsMrVIAandMrVIB.
WangM, etal. (2007)Thecrosschannelactivitiesofspiderneurotoxinhuwentoxin-Ionratdorsalrootganglionneurons. BiochemBiophysResCommun. PMID: 17451655
EffectofHuwentoxin-IontheFasandTNFapoptosispathwayinthehippocampusofratwithglobalcerebralischemia
Neuronalinjuryisthemostimportantreasonforvariousbraininjuries.CytosolicCa(2+)overloADInghasbeenproposedasoneofthemaincellularprocessesleadingtoneuronaldeathduringcerebralischemia.ItiswellacceptedthatCa(2+)channelblockerscanprotectcerebralneuronsfromischemicinjury.Inthepresentstudies,weinvestigatedthemolecularmechanismfortheneuro-protectiveeffectofHuwentoxin-I(HWTX-I),aspidertoxinselectivelyblockingN-typevoltage-dependentCa((2+))channel,onratmodelswithglobalcerebralischemia-reperfusioninjury.OurstudiesdemonstratedthatHWTX-IcouldmaintainthemorphologicalstABIlityofpyramidalcellsinthismodel.FurThermore,HWTX-Icoulddecreasetheconcentrationofmalon-dialdehyde,butincreasetheactivityofsuperoxidedismutaseandglutathioneperoxidase.ItalsoreducedtheexpressionlevelofrelatedfactorsofFasandtumornecrosisfactordeathreceptorapoptosispathwaysinthehippocampus.Insummary,HWTX-Ihasanobviousneuroprotectiveeffect,whichmayactthroughitsinhibitiononacertainapoptosispathway.
WangYR, etal. (2007)EffectofHuwentoxin-IontheFasandTNFapoptosispathwayinthehippocampusofratwithglobalcerebralischemia. Toxicon. PMID: 17900647
Antinociceptiveeffectsofintrathecallyadministeredhuwentoxin-I,aselectiveN-typecalciumchannelblocker,intheformalintestinconsciousrats
Thepresentstudywasundertakentoelucidatetheantinociceptiveeffectofintrathecaladministrationofhuwentoxin-I(HWTX-I),aN-typecalciumchannelblockerfromthevenomoftheChinesebirdspiderOrnithoctonushuwena(Wang)[=Selenocosmiahuwenawang],bycomparisonwithomega-Conotoxin-MVIIA(omega-CTX-MVIIA)andmorphinehydrochlorideintheformalintestinconsciousrats.Similartoomega-CTX-MVIIAandmorphine,intrathecalpre-treatmentwithHWTX-Iresultedinsuppressionofnociceptivebehaviorinadose-dependentmanner.TheED50valuesofHWTX-Iandomega-CTX-MVIIAwere0.28and0.19microg/kg,respectively.Itwasalsofoundthat,atlowerdoses(0.1and0.5microg/kg),theantinociceptiveeffectofHWTX-Iwasidenticaltothatofomega-CTX-MVIIA,whileomega-CTX-MVIIAactedmoreremarkablythanHWTX-Iathigherdose(1.0microg/kg).However,theantinociceptioninducedbyomega-CTX-MVIIAwerecompaniedwithmotordysfunction,andtheseside-effectsbecamemoreevidentwiththedosesofomega-CTX-MVIIAincreasing.Incontrast,HWTX-Ididnotshowtheseside-effectsatthedosesof0.5-1.0microg/kg.ComparedwithHWTX-Iandomega-CTX-MVIIA,theanalgesiceffectofintrathecalmorphinehydrochloridewasinitiatedfaster,butlastedforashortertime(about2-3hat1.0microg/kg)thanthatofHWTX-Iandomega-CTX-MVIIA(about4-5hat1.0microg/kg).Therefore,thepresentresultsshowthat,likeomega-CTX-MVIIA,theintrathecaladministrationofHWTX-Iiseffectiveinantinociceptionintheratmodeloftheformalintest.
ChenJQ., etal.(2005)Antinociceptiveeffectsofintrathecallyadministeredhuwentoxin-I,aselectiveN-typecalciumchannelblocker,intheformalintestinconsciousrats. PMID: 15581678
TheeffectofHuwentoxin-IonCa(2+)channelsindifferentiatedNG108-15cells,apatch-clampstudy
Huwentoxin-I(HWTX-I),a3.75kDapeptidetoxinisolatedfromthevenomofthespiderSelenocosmiahuwena,wasfoundtobeareversiblepresynapticinhibitorbyourpreviouswork.Usingwhole-cellpatchclampmethods,wefoundthatHWTX-IhadnosignificanteffectontheTTX-sensitiveNa(+)currentorthedelayedrectifierK(+)current(K(r))inlow-serummediumculturedNG108-15cells,butHigh-Voltage-ActivatedCa(2+)channelexpressedinprostaglandinE(1)differentiatedNG108-15cellscouldbepotentlyinhibitedbyHWTX-I(EC(50)approximately100nM),whileithardlyaffectedlow-voltage-activatedCa(2+)channel.Amongtypesofhigh-voltage-activatedCa(2+)channel,HWTX-IselectivelyinhibitedN-typeCa(2+)channelandhadonlyveryweakeffectonL-typeCa(2+)channelinprostaglandinE(1)differentiatedNG108-15cells.
Peng,K., etal. (2001)TheeffectofHuwentoxin-IonCa(2+)channelsindifferentiatedNG108-15cells,apatch-clampstudy, Toxicon. PMID: 11024489
Thepresynapticactivityofhuwentoxin-I,aneurotoxinfromthevenomofthechinesebirdspiderSelenocosmiahuwena
Threedifferenttypesofisolatednerve-synapsepreparations,guineapigileum,ratvasdeferensandtoadheart,wereusedtoinvestigatethephysiologicalactivityofHuwentoxin-1,aneurotoxinfromthevenomofthespiderSelenocosmiahuwena.ThetwitchresponseofisolatedguineapigileuminducedbyelectricalstimuluscanbeinhibitedbyHWTX-I.Afterblockage,contractionoftheileumcanbeinducedbyexogenouslyappliedacetylcholine.HWTX-Icausedtheinhibitionofthetwitchresponsetoelectricalnervestimulationintheratvasdeferens.Afterthetwitchwascompletelyinhibited,noradrenalinetriggeredrhythmiccontractionofthevasdeferens.Theinhibitoryeffectonheartoftoadinducedbystimulatingsympathetic-vagusnervecanbereversedbyHWTX-I,althoughexogenouslyappliedacetylcholinestillactsasaneffectiveinhibitor.AlloftheseresultssupporttheconclusionthatHWTX-Ihasthepresynapticactivitythateffectsthereleaseofneurotransmitterfromthenerveendingsofboththecholinergicsynapseandtheadrenergicsynapse.
Liang,S.P., etal. (2000)Thepresynapticactivityofhuwentoxin-I,aneurotoxinfromthevenomofthechinesebirdspiderSelenocosmiahuwena, Toxicon. PMID: 10736477
Blockadeofneuromusculartransmissionbyhuwentoxin-I,purifiedfromthevenomoftheChinesebirdspiderSelenocosmiahuwena
Huwentoxin-1(HWTX-I)isaneurotoxicpeptidepurifiedfromthevenomoftheChinesebirdspiderSelenocosmiahuwena.TheeffectsofHWTX-Ionneuromusculartransmissionofvertebrateskeletalmusclehavebeeninvestigatedbymeansoftwitchtensionandelectrophysiologicaltechniques.Onisolatedmousephrenicnerve-hemidiaphragmpreparations,HWTX-Iblockedthetwitchresponsestoindirect,butnottodirect,musclestimulation.Thetimeneededforcompleteblockoftheneuromusculartransmissionwasdosedependent.ThetransmissioncouldbemostlyrestoredbyprolongedrepeatedwashingwithTyrode’ssolution.IfthepreparationwaspretreatedwithD-tubocurarineandthenimmersedinamixedsolutionofD-tubocurarineandHWTX-I,thewashouttimenecessarytorestoretheneuromusculartransmissionwassignificantlydecreased.Intracellularrecordingattheend-plateregionoffrogsartoriusmusclerevealedthatHWTX-Icouldsynchronouslyreducetheamplitudeoftheacetylcholinepotentialinducedbyionophoreticapplicationofacetylcholineaswellastheamplitudeoftheend-platepotentialevokedbynervestimulation.Bothoftheseeffectseventuallydisappeared;however,bothcouldberestoredbyprolongedwashing.ExperimentsonXenopusembryonicmyocytesindicatedthatHWTX-Ireducedtheopenprobabilityofacetylcholine-inducedchannelactivity,andfinallyblockedthechannel.AlloftheseresultsdemonstratedthatHWTX-Iwasapeptideneurotoxinandthepostsynapticnicotinicacetylcholinereceptorwasitssiteofaction.
Zhou,P.A., etal. (1997)Blockadeofneuromusculartransmissionbyhuwentoxin-I,purifiedfromthevenomoftheChinesebirdspiderSelenocosmiahuwena, Toxicon. PMID: 9028007
Propertiesandaminoacidsequenceofhuwentoxin-I,aneurotoxinpurifiedfromthevenomoftheChinesebirdspiderSelenocosmiahuwena
Bymeansofreversephaseandion-exchangehighperformanceliquidchromatography,aneurotoxicpeptidenamedhuwentoxin-IwaspurifiedfromthevenomoftheChinesebirdspiderSelenocosmiahuwena.TheintraperitonealandintracisternalLD50inmiceofthetoxinwere0.70mg/kgand9.40micrograms/kg,respectively.Thistoxinattheconcentrationof1x10(-5)g/mlcanirreversiblyblocktheneuromusculartransmissionoftheisolatedmousephrenicnerve-diaphragmpreparationin13.4+/-1.3min(mean+/-S.D.,n=5).Theisoelectricpointis8.95determinedbyisoelectricfocusingelectrophoresis.Itconsistsof33aminoacidsincluding6Cysand6Lysdeterminedbyaminoacidanalysis.Thecompleteaminosequenceofhuwentoxin-1wasdetermined.TheN-terminalandC-terminalresidueswereAlaandLeu,respectively.Theprimarystructureshowedpartialhomologywiththatofmu-agatoxinsfromthefunnel-webspiderAgelenopsisaperta.
Liang,S.P., etal. (1993)Propertiesandaminoacidsequenceofhuwentoxin-I,aneurotoxinpurifiedfromthevenomoftheChinesebirdspiderSelenocosmiahuwena, Toxicon. PMID: 8212049
