Neuro-Immuno-Teratogenicity of Drugs Used in Neonatal Pharmacotherapy in Relation to the Ontogenic Stage at the Time of Their Administration

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1 Gen Physiol Biophys (1999), 18, Focus Issue, Neuro-Immuno-Teraogeniciy of Drugs Used in Neonaal Pharmacoherapy in Relaion o he Onogenic Sage a he Time of Their Adminisraion 0 BENEŠOVÁ 1, H TEJKALOVÁ 1, Z KRIŠTOFIKOVÁ 1, V PANAJOTOVA 2 AND P HUŠEK 3 1 Prague Psychiaric Cener, Prague 8, Czech Republic 2 Research Insiue for Pharmacy and Biochemisry, Prague 3, Czech Republic 3 Insiue of Endocrinology, Prague 1, Czech Republic Absrac. The risk of funcional eraogeniciy of wo drugs used in neonaal pharmacoherapy was sudied mdomehacin () and dexamehasone () Model experimens were carried ou in Wisar srain ras, breed Konárovice, which received single subcuaneous drug injecion ( 2 mg/kg, 1 mg/kg) on posnaal day 4 (PD 4, model of human feus/preerm newborn of 6-7-monhgesaional age) or on posnaal day 9 (PD 9, model of full-erm human neonae) The ras were followed up during developmen (body weigh, mauraion) ill lae adulhood (age 6-8 monhs) using ess of cogniion, immune reaciviy and biochemical brain analysis The resuls evaluaed by comparing reaed and conrol lier-maes indicaed ha he funcional eraogenic risk was significanly higher in han in -ras revealed disorganizaion of developmenal processes reardaion of body growh, bu acceleraion of sensory developmen (pinna and eye opening), rearded male sexual mauraion Adul -ras (age 6 monhs) of boh series (PD 4, PD 9) had defici of shor-erm memory (social recogniion es) Disurbances of immune reaciviy (decrease of humoral and rise of cell-mediaed immune response) appeared boh in adul and -ras (age 7 monhs), bu only in he PD 9 series i e when he drugs were adminisered a a higher sage of he onogenic developmen simulaing neonaal period in humans This finding may be warning from he clinical poin of view for he neonaological pracice Key words: Drug eraogeniciy Perinaal pharmacoherapy Indomehacin Dexamehazone Immunooxiciy Inroducion Drugs adminisered for perinaal reamen of pregnancies-a-nsk and neonaes-arisk may inerfere wih he gene conrolled, ime and space deermined programme Correspondence o Prof MUDr Olga Benešová DrSc, Prague Psychiaric Cener, Úsavní 91, Prague 8, Czech Republic benesovaqpcp If 3 cum cz

2 22 Benešová e al of developmenal processes and iniiae disorganizaion of perinaal onogenesis which is characerized by inensive cyodiffereniaion and recepor formaion in he already shaped organs (e.g. brain, immune and endocrine sysem). These disurbances on he cellular/subcellular level are no eviden a birh, bu form he basis for funcional defecs of menioned organs (funcional eraogeniciy) which become manifes gradually during furher developmen and mauraion as various neuropsycho-behavioural deviaions or disorders of immunocompeence (Benešová 1995). The presen sudy evaluaes - in model experimens in ras - he risk of funcional eraogeniciy of wo drugs used in obserics and neonaology: indomehacin given o newborns-a-risk o preven inravenricular hemorrhage or o accelerae he closure of paen ducus areriosus (Gersony e al. 1983; Hanigan e al. 1988; Men e al. 1988) and dexamehazone prescribed o induce surfacan producion in immaure feal/neonaal lung and hus o preven/rea he neonaal respiraory disress syndrome (Liggins and Howie 1972; Soil and McQueen 1993). Since he esed drugs are applied clinically boh o full-erm neonaes and o premaures of various gesaional age he sudy focused on he quesion wheher drug adminisraion a differen sages of perinaal onogenesis could change he qualiy or quaniy of he funcional eraogenic risk. Comparaive developmenal sudies in several species of laboraory animals and man (Dobbing 1973, Romijn e al.1991) have shown ha - concerning brain onogenesis - neonaal ra is comparable wih he human feus a monh 6 of gesaion or wih he preerm newborn of he same gesaional age, whereas only 9-12-day-old ra pups may represen he model for he full-erm human neonae. Consequenly, in he presened model experimens in ras, he esed drugs were adminisered o ra pups as a single subcuaneous injecion of a clinically relevan dose eiher on he fourh or on he nineh posnaal day The animals were followed up during heir developmen and mauraion ill lae adulhood (age 6-8 monhs) using ess of behaviour, immune reaciviy and brain biochemical analysis. Maerials and Mehods Experimens were carried ou in Wisar srain ras, breed Konárovice Drugs were adminisered m clinically relevan doses (indomehacin - 2 mg/kg, dexamehazone - 1 mg/kg) as a single subcuaneous injecion o neonaal ra pups on posnaal day 4 (PD 4) or posnaal day 9 (PD 9) One half of every 10-member lier received he esed drug, he oher half received saline (conrol group) The pups were weaned on day 28, divided according o gender, aooed, housed in plasic cages m groups of 5, laer on of 2 animals, and mainained under sandard laboraory condiions m naurally li room wih deailed records of parenage, age, healh condiion ec ill he age of 8 monhs In he course of he firs seven weeks, following developmenal landmarks were regisered body weigh, incisor erupion, pinna and eye opening, sexual mauraion in females (vagina opening) and males (prepuium loosening) In adul male ras a he age of 6-8 monhs, cogniive behaviour, immunoreaciviy and bram biochemical analysis were evaluaed Social recogniion es ("social memory") Modified mehod Thor and Holloway 1982 Three 5-mm-sessions (inerval 45 mm ) wih

3 Drug Neuro-Immuno-Teraogemciy 23 he exposiion of one ra pup (age days) in firs wo sessions and wih an oher pup in he hird session Elemens of approach behaviour (sniffing, ouching, following he pup) based predominaly on he olfacory discriminaion (he main sensory analyzer in ras) were checked and he difference beween he social ineres for he familiar and for he novel pup was evaluaed The behaviour of ras was videoaped The duraion of he menioned behavioural elemens were regisered using "ACTIVITY" sofware for PC and evaluaed by saisical programs BMDP Immune funcion ess a) Humoral immune response - anibody producion agains ovalbumin b) Cell-mediaed immune response - delayed ype of hypersensiiviy (DTH) o bovine serum albumin Brain biochemical analysis Afer decapiaion, brains were quickly removed and - using an ice cooled plae - disseced in 4 pars (corex, hippocampus, hypohalamus, sriaum) The following biochemical markers were deermined a) Markers for monoaminergic ransmission - concenraion of noradrenaline (NA), dopamine (DA), seroonin (5-HT) and heir meabolies (dihydroxyphenylaceic - DOPAC, homovamhc - HVA, 5-hydroxyindoaceic acids - 5-HIAA) in he sriaum and he hypohalamus (high performance liquid chromaography asssay wih elecrochemical deecion) b) Marker for cholinergic neuronal aciviy - high affiniy choline upake (HACU) in he hippocampus (mehod according o Krišofiková e al 1992) c) Marker for free radical induced neuronal damage - lipid peroxidaion (LPO) in he corex and he hippocampus (mehod according o Ohkawa e al 1979) Resuls The preweaning developmen and mauraion was moniored m 210 ra pups from PD 4 series and in 160 from PD.9 series. The comparison of body growh in conrol pups and heir reaed her-maes indicaed no differences in -ras of boh series -pups revealed significan growh reardaion in he firs wo weeks afer he drug injecion, especially in PD-9 series, bu, a weaning, heir body weigh aained normal values In conras o his body growh deceleraion, he sensory developmen (pinna and eye opening) in -pups of boh series was significanly acceleraed. On he oher hand, male sexual mauraion was rearded (wih significan difference in PD.9 series), hus indicaing gross disorganizaion of developmenal processes induced by adminisraion a he neonaal age (Table 1) The impac of on he developmen and mauraion was sligh, eviden only in preweaning ras as minor reardaion of eye opening. In adul animals a he age of 6 monhs, disurbance of cogniive behaviour (social memory es) was found in -ras of boh series, whereas in -ras, only some insignifican defici appeared in PD:9 series (Table 2). Adminisraion of boh and in he neonaal period resuled in disurbances of adul immune reaciviy (decrease of humoral and increase of cell-mediaed immune response), bu only in PD:9 series (Table 3) Neurobiochemical analysis of adul

4 24 Benešová e al Table 1. Developmen and mauraion of ras adminisered, rol) on posnaal day 4 (PD 4) or posnaal day 9 (PD 9) or saline (con- Series PD:4 PD:9 Age posnaal day Developmenal landmark CONTROL CONTROL eye 26/97 6/52 53/60 8/62 3/52 14/44 14 opening (m+f) 27% 12% 88% 13% 6% 32% í í ** * 40 prepuium 49/61 25/35 25/37 29/30 32/32 15/30 loosening (m) 80% 71% 68% 97% 100% 50% ** The resuls are expressed as he raio [No of ras wih he landmark/oal No of ras] or as percenages of posiive evens m=males, f=females * p < 0 05, ** p < 0 01 í Table 2. Social memory in adul male ras (age 6 monhs) PD:4 PD:9 CONTROL CONTROL 4/8 50% 3/6 50% * 0/6 0% 5/7 71% 3/7 43% * 1/7 14% The resuls are expressed as he raio [No of ras wih correc reacion/oal No of ras] or as percenages of correc reacions animal brains (Table 4) indicaed no differences from conrols when or were applied on PD:4. A he higher sage of onogenic developmen (i.e PD:9), induced several deviaions which migh signify impaired funcioning: rise of lipid peroxidaion in he corex (+20%, p < 0.01), increased dopamine urnover in he hypohalamus (+46%, p < 0.01), lower cholinergic neuronal aciviy in he hippocampus. On he oher hand, hippocampal cholinergic aciviy (HACU) in -ras was slighly increased.

5 Drug Neuro-Immuno-Teraogeniciy 25 Table 3. Immunoreaciviy m adul male ras (age 7 monhs) Series PD:4 PD:9 Immune response Humoral (anibody producion) -34 %** -35 %* Cell-mediaed (DTH) +25% +64 %' +108 %* N = (per drug group) The resuls are expressed as percenages of increase (+) or decrease ( ) or no difference in comparison wih conrols * p < 0 07, *p < 0.05, **p < 0 01 Table 4. Brain biochemical analysis in adul male ras (age 7-8 monhs) Series PD:4 PD:9 Assay CORTEX lipid peroxidaion + 17% +20 %** HIPPOCAMPUS HACU +26% -25 % HYPOTHALAMUS dopamine (DA) DOPAC homovamlic acid (HVA) HVA+DOPAC/ DA +24% +21 % -21 % +21 %* +46 %** STRIATUM seroonin (5-HT) 5-HIAA 5-HIAA / 5-HT +9% +11 %* +9% +10 %* For furher descripion, see Table 3 Discussion Model experimens in ras simulaing he perinaal adminisraion of or in he reamen of high-risk neonaes of differen gesaional age indicaed significan differences in he funcional eraogenic risk no only beween boh esed drugs, bu also in relaion o he onogenic sage a he ime of he drug applicaion.

6 26 Benešová e al. As far as differences beween boh drugs are concerned, experimenal resuls from he follow-up of developmen and mauraion, as well as from he ess of adul behaviour and neurobiochemical brain analysis, showed weaker funcional eraogenic effecs of neonaal adminisraion. induced significan disurbances already in preweaning developmen and mauraion of ra pups showing a conras beween body growh reardaion on one hand and acceleraion of he sensory developmen (pinna and eye opening) on he oher hand, in boh series of experimens (i.e. PD:4 and PD:9). I is worh of menioning ha his early developmenal discrepancy was described already in our previous sudy when was applied on PD:7 (Benešová and Pavlik 1989). Addiionally, he presen eperimens showed ha sexual mauraion of male -ras was significanly rearded. This mozaic of developmenal acceleraion as well as reardaion seems o be ypical for neonaal use of since inadequae acivaion of glucocoricoid recepors may resul boh in precocious inducion and premaure erminaion of imporan onogenic processes (e.g. cell proliferaion and differeniaion). Lae behavioural consequences of single neonaal adminisraion of esed drugs were evaluaed in adul male ras (age 6 monhs). Significan defici of memory (social recogniion es) was found in adul -ras of boh experimenal series i.e. PD:4 and PD:9. This finding is in agreemen wih our previous resuls (Benešová and Pavlik 1989) which indicaed cogniive impairmen in ras afer adminisraion on PD:7, using various ess of learning and memory (acive and passive avoidance, food rewarded appeiive learning). In adul -ras, only a sligh insignifican decrease of social memory appeared in PD:9 series. The mos ineresing resuls were found in esing immunoreaciviy of adul and animals. Boh drugs induced significan deviaions of immune reaciviy (in erms of a decreased humoral and increased cell-mediaed immune response), bu only afer drug adminisraion a he higher onogenic sage (i.e. PD:9). A similar dependence of lae immunological disurbances on he sage of onogeny a he ime of drug adminisraion was found in our previous sudy wih diazepam (Benešová e al. 1997). Diazepam (10 kg/kg) applied on PD:9-10 induced significan decrease of cell-mediaed immune response in adul male ras, bu he same diazepam dose applied on PD:4-5 resuled in no lae immune defecs. These resuls wih hree differen drugs may lead o he conclusion ha he risk of immunoeraogeniciy is higher when he drug is applied in more advanced onogenic phase, corresponding in ras o posnaal days 9-10 (model of full-erm human neonae). Disurbances of brain biochemical markers in adul ras adminisered neonaally wih he esed drugs appeared - similarly as in ess of immunoreaciviy - only in PD:9 series i.e. when he drugs were applied a he higher onogenic sage. In adul -ras, several significan deviaions were found he characer of which may be inerpreed as impaired funcioning (rise of lipid peroxidaion in he corex, increased dopamine urnover in he hypohalamus, lower cholinergic aciviy in he hippocampus). On he oher hand, -ras revealed an increase of hippocampal cholinergic aciviy which migh be considered as a posiive impac.

7 Drug Neuro-Immuno-Teraogeniciy 27 Conclusion Model experimens wih ras showed ha he funcional eraogenic impac of perinaal pharmacoherapy is highly dependen on he onogenic sage a he ime of he drug adminisraion. The finding concerning he risk of significanly disurbed adul immunoreaciviy when he esed drugs (indomehacin, dexamehazone, diazepam) were applied a a higher sage of onogeny (PD:9 - model of human neonaal period) may be warning from he clinical poin of view for neonaal herapy pracice. Acknowledgemens. The sudy was suppored by he grans IGA MZČR No and No References Benešová O (1995) Drug reamen in perinaal period and he risk of funcional eraogeniciy Arch Toxicol Suppl 18, pp Benešová O, Pavlik A (1989) Perinaal reamen wih glucocoricoids and he risk of maldevelopmen of he brain Neuropharmacology 28, Benešová O, Tejkalová H, Panajoova V, Krišofiková Z, Pomelová M, Velíšek L (1997) Diazepam exposure a differen sages of neonaal onogeny and neuroímmune-behavioural reaciviy in adul ras Arch Physiol Biochem 105, 299 Dobbing J (1973) The developing bram a plea for more criical inerspecies exrapolaion Nur Rep In 7, Gersony W M, Packham G J, Ellison R C, Miemen O S, Nadas A S (1983) Effecs of indomehacin m premaure infans wih paen ducus areriosus Resuls of a collaboraive sudy J Pedia 102, Hanigan W C, Kennedy G, Roemisch F, Anderson R, Cusack T, Powers W (1988) Adminisraion of indomehacin for he prevenion of perivenricular-inravenricular hemorrhage m high-risk neonaes J Pedia 112, Krišofiková Z, Klaschka J, Tejkalová H, Benešová O (1992) High affiniy choline upake and muscarinic recepors in ra brain during aging Arch Geronol Geriar 15, Liggins G C, Howie R N (1972) A conrolled rial of aneparum glucocoricoid reamen for prevenion of he respiraory disress syndrome in premaure infans Pediarics 50, Men L R, Duncan Ch C, Ehrenkranz R A, Kleinman Ch S, Taylor K J W, Sco D T, Gener P, Sherwoni E, Williams J (1988) Randomized low-dose indomehacin rial for prevenion of inravenricular hemorrhage in very low birh weigh neonaes J Pedia 112, Ohkawa H, Ohishi N, Yagi K (1979) Assay for lipid peroxides m animal issues by hiobarbiunc acid reacion Anal Biochem 95, Romijn H J, Hofman M A, Gramsbegen A (1991) A wha age is he developing cerebral corex of he ra comparable o he full-erm human newborn baby 7 Early Hum Dev 26, Soil R F, McQueen M C (1993) Respiraory disress syndrome In Effecive Care of he Newborn Infan (Eds J F C Sinclair, M B Bracken) pp , Oxford Univ Press, New York Thor D T, Holloway W R (1982) Social memory of he male laboraory ra J Comp Physiol Psychol 96,

8 28 Gen Physiol Biophys (1999), 18, Focus Issue, The Influence of a-lipoic Acid on he Toxiciy of Cadmium M BLUDOVSKÁ, D KOTYZOVÁ, J KOUTENSKÝ, V EYBL Deparmen of Pharmacology and Toxicology, Charles Universiy, Faculy of Medicine, Pilsen, Czech Republic Absrac. a-lipoic acid (a-la) is an imporan anioxidan drug wih chelaing properies In experimens performed in male mice (CD-I, Charles River) he effecs of cadmium on lipid peroxidaion (LP), GSH level, he aciviy of caalase and gluahione peroxidase (GSH-Px) in liver homogenaes were sudied Mice were injeced wih CdCl2 2 5 H 2 O a a dose of 40 /iinol kg -1 s c a-la was adminisered simulaneously i p a he dose corresponding o a-la-o-cd molar raio of 5 1 The experimens were compleed a 24h Cadmium increased LP o 200 7% of conrols This effec was prevened by a-la reamen (p < 0 05) GSH level was decreased o 81 7% of conrols and i was no affeced by a-la GSH-Px aciviy diminished by Cd adminisraion was correced by a-la (p < 0 001) Caalase aciviy decreased by Cd remained unaffeced The adminisraion of a-la alone enhanced LP and he aciviy of caalase As esimaed by AAS, Cd conen in he liver, he kidneys, he brain and he eses remained unaffeced by a-la reamen In he acue oxiciy experimen, he moraliy associaed wih cadmium was decreased by a- LA adminisraion The resuls sugges ha he oxiciy of Cd was decreased mainly by he anioxidan aciviy of a-la raher han by cadmium removal from issues Key words: Cadmium a-lipoic acid Oxidaive saus Inroducion a-lipoic acid (a-la) [6,8-hiocic acid, l,2-dihiolane-3-penanoic acid] is a naurally occurring subsance I is presen in all kinds of prokaryoic and eukaryoic cells and funcions as a cofacor in he mulienzyme complexes ha caalyze he oxidaive decarboxylaion of a-keo acids a-la is a poen anioxidan, and i has been shown o be an efficien chelaor of several meals Lipoic acid /3-oxidaion producs (bisnorhpoae and eranorhpoae) and dihydrohpoic acid (DHLA), a reduced form of lipoic acid, conribue o he anioxidan aciviy of a-la DHLA is a poen anioxidan bu by virue of is abiliy o chelae and reduce iron i also shows pro-oxidan aciviy (Biewenga e al 1997, Packer e al 1996, 1997) Correspondence o MUDr Monika Bludovska, Deparmen of Pharmacology and Toxicology, Charles Universiy, Faculy of Medicine, Karlovarská 48, Plzeň, Czech Republic bludovskqlfp cum cz