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Iglial cell production of no: possible role in multiple sclerosis
31 RESPONSE OF GLIAL CELLS TO DOP AMINERGIC NEURO’I0XICITY
INDUCED BY MF’l’P (I-METHYL4PHENYL-1,2,3,6-WROPYRIDINE) IN MICE M.Kohutniolm, LKurkowska-Jastr&&. A.Czlonkow&i. A.C&&&tg Mcdica Academy, Jnatitute ofPayohtatty and Neurology, Warsaw, Poland MPTP aeleotiveJy deatmya the dopam&rgic neuronsofthenigmeumuu pathway inducing changes similar to those ohmrved in Patients with Parkinson’s disease.. Reaction of mioruglia and a&oqtes has been deecribed in several neuroPathological conditiona. In the preaont irweatigation we have studied response ofthesecells following JvEJlP tmatment in mice. MiCtoglial c&s were stained by lectin derivud from Griffonia simplicifolia, a&oqtea by anti-GFAP and do~m&s+c neurons by antiT-Hantibodies. The presence of lL-6 was esthm@d by anti-IL-6 antibody. The activation of mioroglia (increase in cells mmrber and changes of morphology ) was ohserved from the 1st day following M?lP treatment in su~nigraandstriatumachievingmaximumonthe~y2~3. Response of the micmgha was followed by astroglial reaction in them regions. Dqletion of dopaminergic neurons wasmostpronoun&7days following MPTP tmatment. These e&cts were blocked by pmmmtment with pargyline - inhibitor of monoamine oxidaac B. Positive staining for lL-6 on mioroglia and asvocytcs was also &served. GliaJ reaction appears to be an early marker of dopamincrgic ncunms damage following MPTP intoxication, but its role in the sequence of p+ological changes needs further cvahmtions.
33 ADMINISTRATION OF NJTRlC OXJDE (NO) SYNTHASE JNHIBJTORS lN EXPBRIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS (EAE) J. Zielasek, S. Jung, K.V. Toyka and H.P. Hsrtung. Dept. of Neurology, Julius-Maximilians-Universitat, WtImburg, Germany. Experimental autoimmune cncephalomyelitis (EAE) is sn animal model mimicking some aspects of multiple sclerosis. It has been shown in mice with RAE, that NO is produced in the CNS. The administrstion of NO synthase inhibitors reduced disesase severity. We fmmd that cytokines sctivste NO synthsse in Lewis mts and studied the possible role of NO in Lewis rat EAE. The administration of the NO synthase inhibitor aminoguanidine in Lewis rst myelin basic protein-induced EAR resulted in * significant enhancement of peak disease senrity. The administrstioo of other NO synthsse inhibitors (Nmonomethylerginine, N-nitro arginine, nitm-arginine methyl ester) had little or no effect in MBP- and T-cell line mediated EAE of the Lewis rat. In smmnmy, NO synthsse appears to play a more oompkx role in the pethogemsis of EAR than previously thought.
35 ~LIGODENOROCVTE DEVElOPYENT. OAS.
IMJURV AID REPAIR
compston
University of Cambridga, Cambridge, UK Oligodandmcyte precursors am born around the ventricles from wham they migrate, prolifsrate and diffamntiata into myafbwting calf% In vitro studias hare charactarii there saparata stagas and have estabkhad tha rots of many dafhwd growth factors and signafs exchanged during gliaf-nsuronal contact in estabgshing the cellular architactura of myelinatad axons. Ramyalinatian occurs in savwal human and sxparimantal disaasas and this may rasult from the availability of ofigodandrocytsprogenitors which am prasant in the adult lrodant and human) narvous system. Oligodandroc~as saam to ba unduly swwitiva to injur’v bv inflwmnatory nwdiators; modal sv;tams which have ilkminatad the machanismof gtial injjry, and which may also be mlavant in disaasa, show that ofigodwrdrocytesam vubwrabla to dimct attach by soluble kwwma mediators and thosa whfch am dativarad on the surfaa of micmgks. In aach situation, altarad mambrana permeability laads to an incraasa in intracafbrlar cafcfum which may prow lethal but can ba rasktad by calcium buffadng and mambrana repair; in vitro studies have damonstratad tha role of cytofdm and growth factors in promoting and. protecting oligodwrdmcytesfrom injury by inflwrwratory mediators.
32 TROPHlC RESPONSES OF ASTROCYTES IN HIPPGCAMPUS OF RAT EXPOSED TO TRlMETHYLTJN B.Gderfeld-Nowak,D.KoczyL,M.Skup and M.Z.arembs Nencki Institute of ExperimentsI Biology,Wsrsaw,Poland Trimethyltin(TMT) is sn enviro-ml neumtoxm.lt destroys specific subfields of the bippocsmpus in the rat causing degeneration of pyramidal cells,iater on accompanied by plastic events including nerve fiber sprouting and dendritic remodehng.TMT administmtion meuhs also in extensive gliosis especially evident in the hippocempus. The hypothesis that reactive sstmcytes in TMT intoxicated rats may have the capacity to express nerve growth foctor(NGF) activity, that could support neuronal plastic responses, was examined in this study. Adultmale Wistar rats were injected with s single dose of Bmg/kg i.p of TMT and inveatignted at 7,14,21 and 60 days after injection.We have found that many reactive astmcytes, especially in m8ion.s of intense plastic mspome$CAl and molecular layer of the dentate gyms) becnme NGPimmun-tive.The reaction already visible at 7 days is intensified at later postiqjectioo periods.Jnduction of NGF-lR in astrocytes is sccompsnied by 80 induction of high affinity NGF receptor(TrkA) immmmmectivity. An early induction of interbeukin -lbeta,known to stimulate NGF synthesis,hss been observed in microglia.LPter oqsn intense immunoresctivity of interleukin-1 beta was observed in astrocytes in the ssme areas ss NGF and TrkA-IR. The data support the ides that glia ceUs,pmviding tmphic support, may be involved in neuronal plastic events sssccisted with TMT treatment.
34 ICLIAL CELL PRODUCTION OF NO:POSSIBLE ROLE IN MULTI-1 PLE SCLEROSIS. M. Ding, B. St.Pierre, B. Mitrovic, L.J. Ignarro and J.E. Merrill, UCLA School of Medicine, Los Angeles, CA. 90024 USA Multiple Sclerosis (MS) is an autoimmune inflammatory, demyelinating disease, which we hypothesize is partly mediated by the production of free radicals of nitrogen and oxygen derived from blood macrophages and endogenous glia. Using the chemical donor SNAP, we have examined the toxic effects of NO on rat glia in vitro. There was preferential damage to oligoden-drocytes which included lowered MBP mRNA levels, mitochondrial and DNA damage, and necrotic (but not apoptotic) cell death. Astrocytes were more resistant than oligodendrocytes and microglia were almost completely resistant to the toxic effects of NO. To further relate these findings to human disease, we examined the production of NO by human glia. Both microglia and astrocytes produce iNOS and NO as determined by in situ hybridization, immunohistochemistry, and total NO levels in culture supernatants. These data support the possibility that NO may be produced in MS and may contribute to the disease. 36
GLULCELLREACi'IONSTODEMYELINATION
INDUCED BY MF’l’P (I-METHYL4PHENYL-1,2,3,6-WROPYRIDINE) IN MICE M.Kohutniolm, LKurkowska-Jastr&&. A.Czlonkow&i. A.C&&&tg Mcdica Academy, Jnatitute ofPayohtatty and Neurology, Warsaw, Poland MPTP aeleotiveJy deatmya the dopam&rgic neuronsofthenigmeumuu pathway inducing changes similar to those ohmrved in Patients with Parkinson’s disease.. Reaction of mioruglia and a&oqtes has been deecribed in several neuroPathological conditiona. In the preaont irweatigation we have studied response ofthesecells following JvEJlP tmatment in mice. MiCtoglial c&s were stained by lectin derivud from Griffonia simplicifolia, a&oqtea by anti-GFAP and do~m&s+c neurons by antiT-Hantibodies. The presence of lL-6 was esthm@d by anti-IL-6 antibody. The activation of mioroglia (increase in cells mmrber and changes of morphology ) was ohserved from the 1st day following M?lP treatment in su~nigraandstriatumachievingmaximumonthe~y2~3. Response of the micmgha was followed by astroglial reaction in them regions. Dqletion of dopaminergic neurons wasmostpronoun&7days following MPTP tmatment. These e&cts were blocked by pmmmtment with pargyline - inhibitor of monoamine oxidaac B. Positive staining for lL-6 on mioroglia and asvocytcs was also &served. GliaJ reaction appears to be an early marker of dopamincrgic ncunms damage following MPTP intoxication, but its role in the sequence of p+ological changes needs further cvahmtions.
33 ADMINISTRATION OF NJTRlC OXJDE (NO) SYNTHASE JNHIBJTORS lN EXPBRIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS (EAE) J. Zielasek, S. Jung, K.V. Toyka and H.P. Hsrtung. Dept. of Neurology, Julius-Maximilians-Universitat, WtImburg, Germany. Experimental autoimmune cncephalomyelitis (EAE) is sn animal model mimicking some aspects of multiple sclerosis. It has been shown in mice with RAE, that NO is produced in the CNS. The administrstion of NO synthase inhibitors reduced disesase severity. We fmmd that cytokines sctivste NO synthsse in Lewis mts and studied the possible role of NO in Lewis rat EAE. The administration of the NO synthase inhibitor aminoguanidine in Lewis rst myelin basic protein-induced EAR resulted in * significant enhancement of peak disease senrity. The administrstioo of other NO synthsse inhibitors (Nmonomethylerginine, N-nitro arginine, nitm-arginine methyl ester) had little or no effect in MBP- and T-cell line mediated EAE of the Lewis rat. In smmnmy, NO synthsse appears to play a more oompkx role in the pethogemsis of EAR than previously thought.
35 ~LIGODENOROCVTE DEVElOPYENT. OAS.
IMJURV AID REPAIR
compston
University of Cambridga, Cambridge, UK Oligodandmcyte precursors am born around the ventricles from wham they migrate, prolifsrate and diffamntiata into myafbwting calf% In vitro studias hare charactarii there saparata stagas and have estabkhad tha rots of many dafhwd growth factors and signafs exchanged during gliaf-nsuronal contact in estabgshing the cellular architactura of myelinatad axons. Ramyalinatian occurs in savwal human and sxparimantal disaasas and this may rasult from the availability of ofigodandrocytsprogenitors which am prasant in the adult lrodant and human) narvous system. Oligodandroc~as saam to ba unduly swwitiva to injur’v bv inflwmnatory nwdiators; modal sv;tams which have ilkminatad the machanismof gtial injjry, and which may also be mlavant in disaasa, show that ofigodwrdrocytesam vubwrabla to dimct attach by soluble kwwma mediators and thosa whfch am dativarad on the surfaa of micmgks. In aach situation, altarad mambrana permeability laads to an incraasa in intracafbrlar cafcfum which may prow lethal but can ba rasktad by calcium buffadng and mambrana repair; in vitro studies have damonstratad tha role of cytofdm and growth factors in promoting and. protecting oligodwrdmcytesfrom injury by inflwrwratory mediators.
32 TROPHlC RESPONSES OF ASTROCYTES IN HIPPGCAMPUS OF RAT EXPOSED TO TRlMETHYLTJN B.Gderfeld-Nowak,D.KoczyL,M.Skup and M.Z.arembs Nencki Institute of ExperimentsI Biology,Wsrsaw,Poland Trimethyltin(TMT) is sn enviro-ml neumtoxm.lt destroys specific subfields of the bippocsmpus in the rat causing degeneration of pyramidal cells,iater on accompanied by plastic events including nerve fiber sprouting and dendritic remodehng.TMT administmtion meuhs also in extensive gliosis especially evident in the hippocempus. The hypothesis that reactive sstmcytes in TMT intoxicated rats may have the capacity to express nerve growth foctor(NGF) activity, that could support neuronal plastic responses, was examined in this study. Adultmale Wistar rats were injected with s single dose of Bmg/kg i.p of TMT and inveatignted at 7,14,21 and 60 days after injection.We have found that many reactive astmcytes, especially in m8ion.s of intense plastic mspome$CAl and molecular layer of the dentate gyms) becnme NGPimmun-tive.The reaction already visible at 7 days is intensified at later postiqjectioo periods.Jnduction of NGF-lR in astrocytes is sccompsnied by 80 induction of high affinity NGF receptor(TrkA) immmmmectivity. An early induction of interbeukin -lbeta,known to stimulate NGF synthesis,hss been observed in microglia.LPter oqsn intense immunoresctivity of interleukin-1 beta was observed in astrocytes in the ssme areas ss NGF and TrkA-IR. The data support the ides that glia ceUs,pmviding tmphic support, may be involved in neuronal plastic events sssccisted with TMT treatment.
34 ICLIAL CELL PRODUCTION OF NO:POSSIBLE ROLE IN MULTI-1 PLE SCLEROSIS. M. Ding, B. St.Pierre, B. Mitrovic, L.J. Ignarro and J.E. Merrill, UCLA School of Medicine, Los Angeles, CA. 90024 USA Multiple Sclerosis (MS) is an autoimmune inflammatory, demyelinating disease, which we hypothesize is partly mediated by the production of free radicals of nitrogen and oxygen derived from blood macrophages and endogenous glia. Using the chemical donor SNAP, we have examined the toxic effects of NO on rat glia in vitro. There was preferential damage to oligoden-drocytes which included lowered MBP mRNA levels, mitochondrial and DNA damage, and necrotic (but not apoptotic) cell death. Astrocytes were more resistant than oligodendrocytes and microglia were almost completely resistant to the toxic effects of NO. To further relate these findings to human disease, we examined the production of NO by human glia. Both microglia and astrocytes produce iNOS and NO as determined by in situ hybridization, immunohistochemistry, and total NO levels in culture supernatants. These data support the possibility that NO may be produced in MS and may contribute to the disease. 36
GLULCELLREACi'IONSTODEMYELINATION