I-methylene blue nezithunywa zemithambo-luvo: i-serotonin, i-dopamine, i-GABA, ne-acetylcholine

Intetho eqhelekileyo nge-methylene blue ithi inyusa i-serotonin, inyusa i-dopamine, izolisa i-GABA, ize ilole i-acetylcholine, konke ngaxeshanye. Loo ntetho ithatha iziphumo ezine ezahlukeneyo zaselabhoratri izenze isiphumo esinye emntwini. Amaphepha ophando exhasa loo ntetho alinganisa iithagethi ezahlukeneyo, kwiisampulu ezilungiselelwe ngeendlela ezahlukeneyo, kumaqondo oxinaniso ahluka malunga nezihlandlo eziliwaka. Xa wohlula iithagethi, umfanekiso uba nomdla ngakumbi, kodwa ufuna nononophelo olungaphezu koluvunyelwa yiloo ntetho inye.

Ingcamango esisiseko ilula. Imolekyuli ebophelela kwi-enzayim kwityhubhu yovavanyo yenze into enye: ibophelele kwi-enzayim kwityhubhu yovavanyo. Ukuba oko kuyalitshintsha inqanaba lesithunywa semithambo-luvo kwingqondo ephilayo kuxhomekeke kuxinaniso olufikelela kwizicubu, kuhlobo lwekhemikhali ekulo imolekyuli xa ifika, nakuyo yonke enye into eyenziwa yimolekyuli kwakulo mgangatho woxinaniso. Icandelo ngalinye elingezantsi ligcina le mibuzo mithathu idityaniswe nesiphumo sophando esihambelana nayo.

I-serotonin: iithagethi ezimbini, amaqondo oxinaniso amabini

Kwezi nkqubo zine, i-serotonin inobungqina obuqine kakhulu, obuvela kwiithagethi ezimbini ezahlukileyo zeemolekyuli ezingafanele zidityaniswe.

Ithagethi yokuqala yi-monoamine oxidase yohlobo A, i-enzayim ekwi-mitochondria eqhekeza i-serotonin. I-MAO-A yomntu ecociweyo iyathintelwa yi-methylene blue esebenza njengesithinteli esibophelela ngokuqinileyo, esine-Ki ekufutshane ne-27 nanomolar, ngoxa i-MAO-B ifuna amaqondo oxinaniso aphezulu kakhulu ngaphambi kokuba ichaphazeleke, njengoko kuboniswe kuphononongo lwekinetiki olwanxulumanisa le dayi nobutyhefu be-serotonin. Olunye uphando oluhambelana nolu lwafumana ukukhetha okufanayo kwizicubu zedlala lepineal lempuku, apho ukuthintelwa kwe-MAO-A kwanyusa ii-indole ezivela kwi-serotonin, kwehlisa imetabolite ye-serotonin eyi-5-HIAA, kwaza kwatshintsha ukusabela kwamasele kokuzibuyisela kwindawo ethe tye okunxulunyaniswa ne-serotonin, njengoko kuchaziwe kuphononongo lweedayi ze-redox nee-indole zedlala lepineal. Iisampulu ezimbini ezilungiselelwe ngeendlela ezahlukeneyo, kodwa indlela yesiphumo iyafana: ukuqhekeka okuncinane, ne-serotonin eninzi egcinwayo apho i-enzayim ibiya kuyisusa khona.

Ithagethi yesibini yiproteni ethutha i-serotonin ngokwayo. Kwiiseli ezivelisa iproteni yomntu ethutha i-serotonin, i-methylene blue yanciphisa ukufakwa kwesubstrate ebengezelayo ne-serotonin enophawu lokulandelela, nge-IC50 emalunga ne-1.4 micromolar. Yanciphisa nemisinga yombane evuswa yi-serotonin kwimilinganiselo ye-patch-clamp, ngokutsho kophononongo olwachaza ngokuthe ngqo ukusebenza kwe-methylene blue kwi-SERT. Ababhali bavavanya ezinye iingcaciso ezicacileyo ezinokubakho, baza bafumanisa ukuba esi siphumo asixhomekekanga ekudluliselweni kwemiqondiso ye-cGMP, kwiinguqu ze-calcium, okanye kubungakanani beproteni ethuthayo kumphezulu weseli.

Qaphela umsantsa phakathi kwala manani mabini. Ukuthintelwa kwe-MAO-A kwenzeka kumaqondo e-nanomolar. Ukuthintelwa kweproteni ethuthayo kufuna idayi eninzi malunga nezihlandlo ezingamashumi amahlanu. Ukuba sesichengeni kwenani elincinane elisebenza ngokupheleleyo kwi-enzayim kusenokungayichaphazeli kangako iproteni ethuthayo. Nabani na odibanisa ezi ziphumo zibe libango elinye nge-serotonin udibanisa uluhlu lwemilinganiselo emibini eyahlukeneyo lube lunye.

Ukuba enye yezi thagethi ibalulekile na kumntu othatha amanye amayeza achaphazela i-serotonin ngumbuzo wamayeza, kwaye ufanele isikhokelo sentsebenziswano yamayeza. Eli nqaku lichaza iithagethi; elo phepha linika iingcebiso zonyango.

I-dopamine: obona bungqina buthe ngqo bubuthathaka

Kwi-dopamine, ukunyaniseka kufuna olona lumkelo lukhulu. Akukho phando lwamkelwe ngokubanzi olubonisa ukuba i-methylene blue ithintela iproteni ethutha i-dopamine okanye ibophelela ngqo kwizamkeli ze-dopamine. I-IC50 yeproteni ethuthayo eyi-1.4 micromolar esoloko icatshulwa yeyethutha i-serotonin, hayi i-DAT, kwaye mayingaze ichazwe ngokutsha ngokungathi yeye-DAT.

Into ekhoyo endaweni yoko bubungqina obungathanga ngqo. Kuba ii-enzayim ze-MAO zikwaguqula i-dopamine, ukuthintelwa kwe-MAO kugcina i-dopamine kunye ne-serotonin ne-noradrenaline. Kwiisampulu ze-mitochondria, i-methylene blue yathintela ukuguqulwa kwetyhefu yemithambo-luvo i-MPTP yi-MAO-B ibe yityhefu eyonakalisa inkqubo ye-dopamine, ngamandla athelekiseka nawesiyobisi se-Parkinson i-deprenyl, njengoko kuchazwe kuphononongo lokuvuselelwa kwe-MPTP ngokwebhayoloji nakuphando olunxulumene ne-MAO-B. Uphando lwezilwanyana longeza iziqwenga zobungqina: ukunyuka malunga nezihlandlo ezintathu kokukhutshwa kwe-dopamine okusisiseko kumacwecwe e-striatum yeempuku kwi-10 micromolar, okuvavanywe kumxholo wokudluliselwa kwemiqondiso ye-nitric oxide kungekhona njengokuthintelwa kweproteni ethuthayo. Emva kokunikwa kwemilinganiselo efikelela kuwo wonke umzimba, iziphumo zahluka kwimimandla eyahlukeneyo, ezinye izifundo zifumana i-serotonin ne-noradrenaline zinyuka ngoxa i-dopamine yayingatshintshi kangako.

Ngoko ibali le-dopamine liyinyani, kodwa lingathanga ngqo. Lidlula kwi-enzayim ephatha ii-monoamine ezininzi ngaxeshanye, kungekhona kwithagethi ekhethekileyo ye-dopamine. Naliphi na ibango lokuba i-methylene blue inyusa i-dopamine ebantwini litsiba inyathelo apho oko bekuboniswe ngokwenene.

I-GABA: ukuthintela isiqhoboshi kwipokotho yokubophelela

Isiphumo sophando nge-GABA sichanekile kwaye siyaphikisana nendlela edume ngayo le dayi. Kwiiseli ezivelisa izamkeli zomntu ze-GABA-A, i-methylene blue yathintela imisinga yombane evuswa yi-GABA ukuqala malunga ne-3 micromolar, nge-IC50 ekufutshane ne-31 micromolar kulungelelwaniso oluqhelekileyo lwe-alpha1-beta2-gamma2, kuphononongo lwe-electrophysiology olwachonga indawo yokusebenza.

Ukuchongwa kwendawo yeyona nto ixabisekileyo. Ukuguqulwa kwendawo ye-picrotoxin akuzange kutshintshe ukuthintelwa, kwaye iindawo ze-benzodiazepine ne-zinc zakhutshelwa ngaphandle ngokuthelekisa iiyunithi ezincinane. Endaweni yoko, ukuguqulwa kweentsalela ezimbini ezaziwayo ukuba zenza ipokotho yokubophelela ye-GABA ngokwayo kwanciphisa kakhulu ukuthintelwa. Oku kubonisa ukuba ukusebenza kukuchasa ngokukhuphisana kwindawo ye-agonist, kungekhona ukuguqula ukusebenza nge-allostery kwenye indawo. Isiphumo saqhubeka kwiindibaniselwano zeeyunithi ezincinane ezikwi-synapse nezingaphandle kwayo, saza saphela ngokukhawuleza xa idayi yahlanjwa yasuswa.

Oku kudala ukungqubana kokwenene okufanele kuchazwe ngokucacileyo. Imolekyuli ephandwa ngenxa yokuxhasa inkumbulo ikwacinezela nokudluliselwa okukhawulezayo kwemiqondiso ethintelayo kwisitya selabhoratri. Ukuba olo cinezelo lwenzeka na kwingqondo ephilayo kuxhomekeke kuxinaniso lwendawo, kwaye i-31 micromolar iphezulu xa ithelekiswa namaqondo amaninzi okufikelela kuwo wonke umzimba, njengoko kuxoxwa kwicandelo lokugqibela. Olo ngquzulwano ngokwalo sisiphumo sophando; ukulucacisa kuya kufuna imifuniselo engekho mntu uyenzileyo.

I-acetylcholine: iindlela ezimbini ezichaseneyo

I-acetylcholine ineziphumo zophando ezimbini ezitsalela kumacala achaseneyo, nto leyo esisizathu sokuba zichazwe ngokwahlukeneyo.

Kwelinye icala, i-methylene blue ithintela ii-enzayim ezisusa i-acetylcholine. I-acetylcholinesterase yeeseli ezibomvu zegazi lenkomo yathintelwa ngokukhuphisana malunga ne-0.57 micromolar, i-enzayim yenkomo kufutshane ne-0.42 micromolar, nokusebenza kwe-esterase kwiplasma yomntu kufutshane ne-1.1 micromolar. I-butyrylcholinesterase yathintelwa kuluhlu olumalunga ne-0.4 ukuya kwi-5.3 micromolar, kuxhomekeka kuhlobo lwesilwanyana nakwindlela yokulungiselela isampulu, njengoko kushwankathelwe kuphononongo lweendlela i-methylene blue esebenza ngazo kwinkqubo yemithambo-luvo. Ukucothisa ukususwa kushiya isithunywa esininzi kwi-synapse, ingqiqo efanayo naleyo ixhasa amayeza amaninzi avunyiweyo e-Alzheimer.

Kodwa le khemistri inomqathango. Uhlobo oluluhlaza olufumene i-oxidation luthintela i-enzayim; uhlobo olungenambala olufumene i-reduction alwenzi njalo. Amaxesha amade okufukama avumela idayi ukuba ifumane i-reduction abonisa ukuthintelwa okubuthathaka ngenxa yeso sizathu kuphela. Naliphi na inani elivela kuvavanyo lwe-cholinesterase lihamba nento engabonakaliyo eguqukayo: ingakanani idayi eyayiseluhlaza xa yayilinganiswa.

Kwelinye icala, i-methylene blue ithintela isamkeli se-nicotine se-alpha7, esinye sezamkeli esisebenza kuzo i-acetylcholine. Izamkeli zomntu ze-alpha7 eziveliswe kwiiseli zamaqanda amasele zathintelwa nge-IC50 ekufutshane ne-3.4 micromolar, ngokuchasa okungakhuphisaniyo nokungaxhomekekanga kumbane, okungazange kutshintshe amandla e-agonist. I-3 micromolar yaphelisa iimpendulo zee-synapse eziqhutywa yi-choline kumacwecwe e-hippocampus yeempuku, njengoko kuchaziwe kuphononongo lwesamkeli se-alpha7. Ngoko kumaqondo afanayo aphantsi e-micromolar, idayi igcina isithunywa kwaye ikwanciphisa nokusebenza kwesinye sezamkeli zaso. Isiphumo esipheleleyo ekudluliselweni kwemiqondiso ye-acetylcholine asinakufundwa kuso nasiphi na kwezi ziphumo sodwa. Oko kungacaci kunxulumene noncwadi olubanzi lophando lwe-Alzheimer, kwakunye nengxoxo enxulumeneyo yophando lokuqonda nezifo, ngaphandle kokusonjululwa apha.

Uthelekiso, kwindawo enye

Ithagethi enovakalelo olukhulu neyona inovakalelo luncinane zahlukaniswe ngamaqondo amathathu obukhulu bezihlandlo ezilishumi. Loo mahluko linqaku liphela kwitheyibhile enye.

Ngaba la maqondo oxinaniso afikelela engqondweni?

Inani elivela kwityhubhu yovavanyo alithethi nto ngaphandle kwenani lobungakanani obufikelela emzimbeni ecaleni kwalo. Emva kwenaliti ekhawulezileyo emthanjeni emalunga ne-1.4 mg nge-kg, kuxelwe amaqondo aphakathi kwiplasma yomntu amalunga ne-5 micromolar, ngoxa umlinganiselo we-100 mg othathwe ngomlomo wavelisa amaqondo egazini elipheleleyo akufutshane ne-0.08 micromolar, kulo mxholo mnye woncwadi lophando. Uphando lokusasazeka kwiimpuku lufumana amaqondo engqondo amalunga nezihlandlo ezilishumi ukuya kwezingamashumi amabini kunalawo ajikelezayo egazini. Noko ke, leyo yidayi iyonke kwizicubu ezenziwe umxube ofanayo, kungekhona idayi ekhululekileyo efumene i-oxidation kwi-synapse. Ukubophelela kwiiproteni zeplasma okukufutshane ne-94 percent, kunye nokwahlulelwa kwiiseli zegazi, kunciphisa ngakumbi inxalenye ekhululekileyo.

Xa kuthelekiswa netheyibhile, ipateni inamaqondo ahlukeneyo endaweni yokuba ibe nguewe okanye nguhayi nje. Ukuthintelwa kwe-MAO-A kwenzeka kude ngaphantsi kwamaqondo aqhelekileyo afikelelwa ngokunikwa emthanjeni, kwaye kuyavakala ngokwekhemesti nanini na idayi inikwa ngaloo ndlela. Iziphumo ze-cholinesterase ne-alpha7 zikuluhlu oluphantsi lwe-micromolar, oludibana namanqanaba aphezulu afikelelwa ngokunikwa emthanjeni kodwa olunokungafikelelwa yimilinganiselo eqhelekileyo ethathwa ngomlomo. I-IC50 ye-GABA-A eyi-31 micromolar ingaphezulu kwamaqondo amaninzi anokufikelelwa ngokusengqiqweni kuwo wonke umzimba, nto leyo eyenza ukuba kube nzima kakhulu ukusebenzisa olo thintelo ukuchaza okwenzeka kumntu opheleleyo. Umqolo ngamnye kolu thelekiso ufuna isilumkiso esifanayo: uxinaniso olubalulekileyo lolwedayi ekhululekileyo, efumene i-oxidation, nengaphandle kweeseli kwithagethi, ubungakanani obungenakulinganiswa ngokuthe ngqo nangaluphi na uvavanyo lwegazi.

Into ongafanele uyigqibe

Akukho mqolo kule theyibhile ongqina ukuba i-methylene blue inyusa okanye yehlisa nasiphi na isithunywa semithambo-luvo emntwini ngendlela enokuqikelelwa. Ukuthintelwa kwe-enzayim kwisampulu ecociweyo, ukuthintelwa kweproteni ethuthayo kuluhlu lweeseli, nokuchaswa kwesamkeli kwicwecwe lezicubu, nganye kuzo ikude nenyaniso yee-synapse ngenyathelo elinye elilawulwayo. Icandelo le-acetylcholine libonisa iziphumo ezimbini eziyinyani eziphikisanayo zize zishiye ukungaqiniseki. Ukusetyenziswa okunoxanduva kweli phepha kukulithatha njengemephu yeethagethi ekuboniswe ukuba le molekyuli ibophelela kuzo, kubhalwe namandla okubophelela, ukuze ingxoxo yeendlela zokusebenza ihlale isekelwe koko kwalinganiswa ngokwenene. Ngokuphathelele indlela ezi thagethi ezisebenzisana ngayo namayeza amiselweyo, isikhokelo sentsebenziswano liphepha elithwala loo msebenzi, kunye nomxholo owongezelelekileyo kwiziseko zekhemesti nakwinkcazelo ehambelana neli nqaku yeendlela zokusebenza.