www.jped.com.br
ORIGINAL
ARTICLE
Improvement
of
autism
spectrum
disorder
symptoms
in
three
children
by
using
gastrin-releasing
peptide
夽
,
夽夽
Michele
Michelin
Becker
a,∗,
Cleonice
Bosa
b,
Vera
Lorentz
Oliveira-Freitas
c,
José
Roberto
Goldim
c,
Lygia
Ohlweiler
a,
Rafael
Roesler
d,
Gilberto
Schwartsmann
e,
Rudimar
dos
Santos
Riesgo
faDepartmentofPediatrics,ChildNeurologyUnit,HospitaldeClínicasdePortoAlegre,PortoAlegre,RS,Brazil
bDepartmentofPsychology,InstitutodePsicologia,UniversidadeFederaldoRioGrandedoSul(UFRGS),PortoAlegre,RS,Brazil cDepartmentofResearchGroupandPost-Graduation,HospitaldeClínicasdePortoAlegre,PortoAlegre,RS,Brazil
dDepartmentofPharmacology,InstitutodeCiênciasBásicasdaSaúde,UniversidadeFederaldoRioGrandedoSul(UFRGS),
PortoAlegre,RS,Brazil
eDepartmentofInternalMedicine,SchoolofMedicine,UniversidadeFederaldoRioGrandedoSul(UFRGS),PortoAlegre,
RS,Brazil
fDepartmentofPediatrics,ChildNeurologyUnit,SchoolofMedicine,UniversidadeFederaldoRioGrandedoSul(UFRGS),Porto
Alegre,RS,Brazil
Received31July2015;accepted12August2015 Availableonline15February2016
KEYWORDS
Gastrin-releasing
peptidereceptor;
Neuropeptides; Autism;
Autismspectrum
disorder
Abstract
Objective: Toevaluate thesafety, tolerability and potentialtherapeutic effectsof
gastrin-releasingpeptideinthreechildrenwithautisticspectrumdisorder.
Methods: Caseseriesstudywiththeintravenousadministrationofgastrin-releasingpeptidein
thedoseof160pmol/kgforfourconsecutivedays.Toevaluatetheresults,parentalimpressions theChildhoodAutismRatingScale(CARS)andtheClinicalGlobalImpression(CGI)Scale.Each childunderwentanewpeptidecycleaftertwo weeks.The childrenwere followedfor four weeksaftertheendoftheinfusions.
Results: Thegastrin-releasingpeptidewaswelltolerated andnochildhadadverseeffects.
Twochildrenhadimprovedsocialinteraction,withaslightimprovementinjointattentionand theinteractioninitiatives.Twoshowed reductionofstereotypesandimprovementinverbal language.Onechildlosthiscompulsiontobathe,aneffectthatlastedtwoweeksaftereach infusioncycle.AveragereductioninCARSscorewas2.8points.CGIwas‘‘minimallybetter’’in twochildrenand‘‘muchbetter’’inone.
夽 Pleasecitethisarticleas:BeckerMM,BosaC,Oliveira-FreitasVL,GoldimJR,OhlweilerL,RoeslerR,etal.Improvementofautism
spectrumdisordersymptomsinthreechildrenbyusinggastrin-releasingpeptide.JPediatr(RioJ).2016;92:302---6.
夽夽StudylinkedtotheHospitaldeClínicasdePortoAlegre(HCPA),PortoAlegre,RS,Brazil.
∗Correspondingauthor.
E-mail:michelemb@terra.com.br(M.M.Becker). http://dx.doi.org/10.1016/j.jped.2015.08.012
Conclusions: Thisstudysuggeststhatthegastrin-releasingpeptideissafeandmaybeeffective in improving key symptoms of autism spectrum disorder, but its results should be inter-preted with caution. Controlled clinical trials---randomized, double-blinded, and with more children---areneededtobetterevaluatethepossibletherapeuticeffectsofgastrin-releasing peptideinautism.
©2016SociedadeBrasileiradePediatria.PublishedbyElsevierEditoraLtda.Allrightsreserved.
PALAVRAS-CHAVE
Receptordopeptídeo
liberadordegastrina; Neuropeptídios; Autismo;
Transtornodo
espectroautista
Melhorianossistemasdotranstornodoespectroautistaemtrêscrianc¸as,utilizando
peptídeoliberadordegastrina
Resumo
Objetivo: Avaliaraseguranc¸a,tolerabilidadeepossíveisefeitosterapêuticosdopeptídeo
li-beradordegastrinaemtrêscrianc¸ascomtranstornodoespectroautista.
Métodos: Estudodecasuísticacomadministrac¸ãointravenosadepeptídeoliberadordegastrina
nadosede160pmol/kgporquatrodiasconsecutivos.Paraavaliarosresultados,foramutilizadas aimpressãodospais,aEscaladeClassificac¸ãodeAutismonaInfância(CARS)eaEscalade ImpressãoClínicaGlobal(CGI).Cadacrianc¸afoisubmetidaanovociclodepeptídeoapósduas semanas.Ascrianc¸asforamacompanhadasporquatrosemanasapósotérminodasinfusões.
Resultados: Opeptídeoliberadordegastrinafoibemtoleradoenenhumacrianc¸aapresentou
efeitos adversos.Duascrianc¸as apresentarammelhoranainterac¸ão social,commelhorana atenc¸ãocompartilhadaenasiniciativasdeinterac¸ão.Duasmostraramreduc¸ãodosestereotipias emelhoranalinguagemverbal.Umacrianc¸aperdeusuacompulsãoporbanhos,efeitoquedurou duassemanasapóscadaciclodeinfusão.Areduc¸ãomédianoescoredaCARSfoi2,8pontos. QuantoàCGI,osresultadosforam‘‘minimamentemelhoremduascrianc¸as’’e‘‘muitomelhor’’ emuma.
Conclusões: Esteestudosugerequeopeptídeoliberadordegastrinaéseguroepodeserefetivo
namelhoradosprincipaissintomasdotranstornodoespectroautista,porémseusresultados devemserinterpretadoscomcautela.Ensaiosclínicoscontrolados,randomizados,duplo-cego ecommaiornúmerodecrianc¸assãonecessáriospara melhoravaliarospossíveisefeitos te-rapêuticosdopeptídeoliberadordegastrinasobreoautismo.
©2016SociedadeBrasileiradePediatria.PublicadoporElsevierEditoraLtda.Todososdireitos reservados.
Introduction
Autism isa pervasive developmentdisorder characterized
by severe impairment in reciprocalsocialization,
qualita-tiveproblemsincommunication,andrepetitiveorunusual
behavior.1Thecurrentestimatedprevalenceofautismisone inevery66children.2Diagnosisisclinicalandtodatethereis nospecifictreatment.3Neurochemical,neuropathological, neuroimaging,andgeneticstudiessuggestsdisorganization ofcorticalneuronsandcerebraldisconnectivity,determined bybothgeneticandenvironmentalfactors.4
Over recent years the effects of endocrine peptides, including gastrin-releasing peptide (GRP), on the central nervous system (CNS) have been investigated.5 GRP is released by glutamatergic neurons and acts as a neuro-transmitter that regulates neuronal excitability.6---8 In the brain,thegastrin-releasingpeptidereceptor(GRPR)ishighly expressedincerebralregionsrelatedtocognitivefunction and emotional processing, such as the dorsal hippocam-pusandbasolateralamygdala.6---9Experimentalstudieshave shown that pharmacological blockade of GRPR in neona-talratsleadstoreducedpreferenceformaternalodorand the developmentof lateand permanent deficitsin social
interaction, a behavior consistent with animal models of autism.10---12
Inthisexperimentalstudy,GRPwasgivenintravenously tothreechildrenwithautismtotestitssafety,tolerability, andpossibletherapeuticeffectsonautismspectrum disor-der(ASD)symptoms.Tothebestoftheauthors’knowledge, thisisthefirstreportofGRPuseinhumanswithautism.
Methods
ChildrenwithautismdiagnosedaccordingtoDiagnosticand
StatisticalManualofMentalDisorders,FourthEdition,Text Revision(DSM-IV-TR),13agedfrom3to18years,were consid-eredsuitableforselection.Exclusioncriteriawereserious clinicaldisorders,psychiatricdiseases,increasedacid pro-duction ingastrointestinal system, secondary autism, and changesinmedicationorothertreatmentsduringthe pre-viousfourweeks.Parentssignedan informedconsentand committedthemselvestomaintainingthecurrenttreatment unchangedduringthestudyperiod.
Alegre(HCPA),Brazil.Thefirstthreechildrenwhometthe abovementionedcriteriawereselected.
GRPwasadministeredata160pmol/kg dosageby con-tinuous intravenous infusion over 30min. Patients were observed for 1h after infusion. Vital signs were moni-tored(arterialbloodpressureandheartrate)every15min. Adverseeffectsweremonitored.Afterwards,thepatient’s familywasencouragedtoreturnnormaldailyroutine.Each childreceivedinfusionsonfourconsecutivedays.
The results were evaluated throughout the Childhood AutismRating Scale (CARS)and ClinicalGlobalImpression (CGI)Scale, bothadministered ontheday beforestarting GRPtreatmentandonthelastdayofinfusion.TheCARSwas translatedandvalidatedforuseinBrazilbyPereiraetal.in 2008.14
Each childunderwent asecond cycle ofinfusionsafter atwo-weekinterval,totestforcause-effectrelationships, andthenfollowed-upweeklyforfourweeks.Thetwo-week interval was chosen based on the duration of objective improvementsobservedinthefirstcase.
Childrenreceivedoral omeprazole duringthe study,to prevent any possible adverse effects from stimulation of acidproductioninthegastrointestinaltract.
The human GRP usedwassynthesizedby Biopetide CO (BiotipeCO.Inc;CA,USA).
The studywasapprovedby theHCPAMedical Research EthicsCommittee(projectNo.11-0277).
Case
reports
Case1
Gisa4-year-oldboy.Heisanagitatedchildandappearsto
haveunlimitedenergy.Heis stubbornandwillnotaccept
beingtold‘‘no’’andwhenheisopposedheattackshimself withblowstothehead,butisnotaggressivetoothers.He
prefersto bealone and does notseek out social
interac-tion.Whenpeopleheknowsattempttointeract,hemakes
eyecontactsporadicallyandhasseriousproblemswithjoint
attention. If people he does not know attempt to
inter-act,heisindifferent.Heexhibitsstereotypicalmovements, walkingontiptoesandsporadicallypointingathisnosewith hisfinger.His onlyinterest is toycars, whichhelinesup,
arranges by color, or removes the wheels from, without
engaginginanytypeofimaginativeplay.Hetakesthemwith himwhereverhegoesandisnotinterestedinanyothertoys.
Heexhibitsunusualfearofthehairdryer,whichsendshim
intoapanic.Heisonlyresistanttochangewithrelationto hisroutetoschool.Hehasritualsforgoingtosleep,anda
fewmonthsbeforethestudyoutset,heacquireda
compul-sionforbathingandmustbewashedfiveorsixtimeseach
day---wheneverhebecomesanxious,hurtshimself,orgets
dirty.Heonlyspeakssingle-wordsentencesandafewshort
phrases. He does not have sensoryabnormalities. He had
been attending school sincehe was1 year and2 months
old,andhasbeen seeing aspeech therapistsince hewas
3yearsold.Hetakes2mgrisperidoneperday.CARS38.5;
CGI:moderatelyill.
Aftertheinfusions,Glosthisobsessionwithbathingand hisfearof the hairdryer, stopped exhibitingstereotypical
behaviorwithhishandsandreducedstereotypicalbehaviors
withhisbody,improvedhistoleranceoffrustrationandhis irritability,and relaxedhispre-sleeprituals. Heexhibited
adiscreteimprovementin thevarietyof hisinterests,his
play,andthequalityofhissocialinteraction,payingmore
joint attention and making initiatives at interaction. The
compulsionforbathingandabnormalfearofthehairdryer
disappeared andthe stereotypicalbehaviorswere
attenu-ated onthefirst dayof infusion. Therewasnochange to
agitation,orverbalornon-verbalcommunication.CARS:34;
CGI-S (severityscale): moderatelyill; CGI-I(improvement
scale):muchimproved.
Theimprovementinobjectivesymptomslastedfortwo
weeks.Afterthisperiod,theboywasadministeredanother
cycleofinfusions,withsimilarresults.Thecompulsionfor
bathing and stereotypical movementswith the hands
dis-appeared onthe firstdayofinfusionsoncemore,andthe
improvementsweremaintainedfortwoweeksafterthelast
infusion.
Gdidnotexhibitanytypeofadverseeffectaftereither
ofthetwoGRPcycles.
Case2
LO is 4-year-oldboy.He hasverbal languageandexhibits
manyecholalias,bothimmediateanddelayed.Heiscalm,
becomingagitatedonlywheninsituationsthatareoutofthe
ordinaryorinstrangeplaces.Whenopposed,hescreamsand
isaggressivetohimselfandothers(biting).Heexhibitsmany stereotypicalbehaviors,suchasswaying,flapping,swinging hishandsinfrontofhiseyes,walkingontiptoes,orrunning
in shortstarts. He does not play imaginativelyand is not
interestedintoys.Heisfascinatedbybrands,logins,letters,
andnumbers.Hedoesnotbecomefixatedonroutines,
rit-uals,ormanias.Hehaspoorsocialinteraction,completely
ignoring hispeers. He makes eye contact with adultsfor
short periods and sometimes seeks them out. He has
lit-tleemotionalresponseandoftenlaughswithoutreason.His
parentsreportthat hehaslittlereactiontopainand
spo-radicallyplacesobjectsinhismouthorsmellsthem.LOhas
regularspeechtherapy,psychologicaland
psychopedagogi-calcare,plusoccupationaltherapyandhorseridingtherapy.
Hewastaking1.5mg/dayofrisperidoneand625mg/dayof
sodiumvalproate.CARS:42;CGI-S:moderatelyill.
AfterGRPinfusions,LOexhibiteddiscreteimprovements
inthequalityofhisverbalcommunication.Hebecamemore
talkative,makingagreaternumberofcommentsand
pro-ducing unrehearsed utterances. Hebecame moretolerant
offrustrationandmoresensitivetopain.Socialinteraction
andstereotypicalbehaviorwereunaltered.CARS40.5;
CGI-S: moderatelyill;CGI-I:minimally improved.LO’s parents
wereunabletodetermine theeffect’sduration.Aftertwo
weekshewasgivenanothercycleofinfusionsandtheresults
lasted until the end of follow-up. He did not exhibit any
adverseeffectsfromGRP.
Case3
L is boy aged 4 years and 3 months. His interpersonal
relationships are highly compromised; he seeks isolation
and will only interact with members of his family after
persistentandvigorousattempts.Hisemotionalresponseis
withoutreason.Hewalksontiptoes,performslittlejumps,
and exhibits flapping and other stereotypical behaviors
with hishands. He is uninterested in toys, does notplay
imaginatively,anddoesnotplaywithchildrenhisownage.
Heisanagitatedboy,heoftenplacesobjectsinhismouth,
and he appears not tofeel pain.He is fascinatedby the
openingtitlesofsoapoperasandpreviewsofthenewson
television.He saysfew words, isnotaggressive,anddoes
not exhibit manias, rituals, or fixation with routines. He
receivesregularpsychologicalandpsychopedagogicalcare,
aswellasspeechtherapy andoccupationaltherapy.Heis
notonmedication.CARS:41;CGI:moderatelyill.
Aftertheinfusions,Lexhibitedanattenuationof
stereo-typical behaviors with the hands and laughter without
reason. His social interaction improved, withmore social
smiling, greater acceptance of interactions initiated by
peers,better jointattention, and bettereye contact.He
becamemoreaffectionate,allowingmorephysicalcontact.
Hisplaybecamemorecreative,takinginawidervarietyof
interests.Hebecamemoretolerantoffrustrationandmore
sensitive to pain. He became more talkative and uttered
somenewwords.CARS:38;CGI-S:moderatelyill,CGI-I:
min-imallyimproved.Hisparentswereunabletodeterminethe
durationoftheeffect.Aftertwoweeks,Lwasgivenanother cycleofinfusionsandtheresultspersisteduntiltheendof follow-up.Thepatientdidnotexhibitanyadverseeffects.
Fig.1illustrateswhichASDsymptomsimprovedafterthe GRPinfusions,bypatient.
Discussion
Over recentdecades,therehas been anexplosive growth
inthenumberofstudiesandpublicationsonthesubjectof ASD.15 Despite this volumeof work, todate no biological markernoranytreatmentscapableofcuringASDhavebeen identified.The availabledrugtreatment only actson sec-ondarymaladaptivesymptoms.Themajorityareprescribed offlabel,sinceonlyrisperidoneandaripiprazolehavebeen approved by the Food and Drug Administration (FDA) for treatment of aggression, irritability, and screamingfitsin patientswithautism.16---18
EvidencehassuggestedalinkbetweenGRPand neuropsy-chiatricdisturbances, but theassociation withautism has received little attention in the literature so far. Genetic studiesin humanshave suggesteda possiblelinkbetween GRPR and regulation of social behavior and bonding. An X;8 translocationonthefirstintron oftheGRPR genehas beenidentifiedinwomenwithmultipleosteochondromaand autism beingtreatedfor mental retardationand epilepsy, indicating that the GRPR gene is one of the candidate genes for autism.19 Recent preclinical studies have raised the hypothesis that some ASD symptoms, such as social interactiondeficits and reduced interest in bonding, may becaused by alack ofGRP action at some early pointin development.10,12
GRP has previously been administered intravenously in humans to test its effects on nutritional intake and vasculardilation.Inonestudyitinducedtransitory vasodila-tor effects, withpressures returning to normal in around 20min.20Inanothertest,GRPwasadministeredatdosesof 10,40,or160pmol/kgperhourtohealthymalevolunteers
Pre-infusion symptoms Post-infusion improvement
Interpersonal relationship deficits
Absence of imitation
Stereotypical movements with body
Stereotypical movements with hands
Absence of emotional response
Inappropriate use of objects
Restricted range of interests
Difficulty adapting to changes
Abnormal auditory response
Poor eye contact
Inappropriate use of touch, smell and taste
Phobias or nervousness
Verbal communication deficit
Non-verbal communication deficit
Agitation
Aggression towards self and others
Compulsions
Rituals
Inappropriate facial expressions
Intolerance of frustration
Unusual interests
Absence of social smiling
Inability to share
Unimaginative play
Incapable of providing comfort
Echolalia
Poor sensivity to pain
Attention Deficit
Case 1 Case 2 Case 3
Figure1 Symptomsofautismdisorderspectrumbeforeand afterintravenousinfusionofgastrin-releasingpeptide(GRP).
inordertoevaluateitseffectoneatingbehaviorandsatiety; theresultsshowedasignificantreductionincalorieintake andareductionofapproximately19%infoodintake.21 The 160pmol/kg doseusedin thepresentcase seriesis larger thaninanyofthesestudies.
Thefewprevious studiesofGRPinhumanshaveshown thatitissafe,whichwasalsoconfirmedinthepresentstudy, sincenoneofthepatientsexhibitedanyadverseeffects.20,21 Theresultsofthiscase seriessuggestthatGRP maybe capableof improving keychildhoodautismsymptoms, for which thereis not currently any specific drug treatment, especiallyforstereotypes.
Inthepresentstudy,twoofthethreepatientsexhibited improvementsinsocialinteraction,withdiscreetchangesin jointattentionandinteractioninitiatives.Thesamepatients also exhibited a reduction in stereotypical behavior, and increasedvarietyofinterestsandimprovedqualityofplay, whichuntilthenhadbeenentirelystereotyped.
Two cases exhibited improvements in verbal language, with more spontaneous speech and use of new words, becamemoresensitive topainandmoretolerantto frus-tration, and exhibited fewer extreme responses such as screamingfitsandaggressiontoselfandothers.
improvementinacompulsionforbathing,whichisan objec-tivevariablethatiseasytomeasureandwhichhadaclear cause-effect relationship, demonstrated when the effect wasrepeatedafterthesecondcycleofGRP.
ThesymptomsthatappearedtohaveimprovedafterGRP infusionsvariedacrossthethreecases,whichmaybe expli-cableby the greatvariety of symptoms observed in each patientpriortotheinfusions,whichisofcoursethereason fortheterm‘‘autismspectrum.’’Whiletheimprovements werediscreet,itimportanttopointoutthatthisis a pio-neeringstudyinwhichpatientsweregivenGRPforjustfour daysatatime.Todatetherearenopublishedstudiesthat haveinvestigatedthesafetyoflong-termadministrationof GRPtohumans.
Although all three families’ responses indicate an improvementintheCGIscores,therewasaverysmall reduc-tioninCARSscores,whichsuggeststhatthescalemaynot havebeensensitive enoughtodetectchangesobservedin thestudy.
In this study, GRP proved safe over the short- and medium-term,incommonwithpublisheddata.
Itisimportanttopointoutthatsincethisisareporton acaseseries,thisstudyhasinherentmethodological limita-tionsandtheresultsshouldbeinterpretedwithcaution.The numberofcaseswassmall,therewerenocontrolsor blind-ing,andtheresultswereassessedonthebasisofparents’ subjectiveimpressions,withnowaytotestfortheplacebo effect.
This study hassuggested that GRP may have an effect onkeysymptomsofchildhoodautism,particularly compul-sionsandstereotypies.Furtherstudiesareneededtobetter evaluatetheseresults,withlargernumbersofpatientsand greatermethodologicalrigor,sinceadministrationofGRPto childrenwithautismprovedpromising.
Funding
Financial support was provided by FIPE-HCPA (Fundo de
InvestimentoemPesquisaseEventosdoHospitaldeClínicas dePortoAlegre).
Conflicts
of
interest
MMB, LO, RSR, GS, and RR are inventors in a patent
application(WO2013185187A1)claimingtheuseof
gastrin-releasingpeptideforthetreatmentofneuropsychiatryand
neurodevelopmentaldisorders.
Acknowledgement
Theauthors aregratefultothefunding agencyFIPE-HCPA
(FundodeInvestimentoemPesquisaseEventos)for
provid-ingfinancialsupportforthisstudy.
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