Contributions
Abstract: P1096
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Neurophysiology
Remyelination is a rare phenomenon of spontaneous regeneration in the central nervous system and is the response that follows demyelination. Experimental autoimmune encephalomyelitis (EAE) is a good model to study inflammation, demyelination and also the remyelination. Optic nerve involvement and visual evoked potentials (VEPs) have been already shown in EAE model induced with myelin oligodendrocyte glycoprotein (MOG) but not with spinal cord homogenate (SCH), with the potential advantage of a milder chronic-relapsing disease. We measured clinical scores daily and VEPs in 7 DA rats at 0, 7 (n=3), 14, 21, 28, 35 and 42 days post injection (dpi) with optic nerve histology at 28 and 42 dpi. A first attack at 9 dpi, peaking at around 12 dpi with complete to partial recovery, followed by a second attack at 20-23 dpi in two subjects and by full recovery with no further attacks in one. VEPs delay was already evident at 7 dpi and persisted throughout, with the exception of the subject with a single attack and full recovery, which was accompanied by bilateral partial recovery of VEPs latencies. Optic nerves at 28 dpi showed dramatic demyelination consistent with VEPs delays and clinical scores. At 42 dpi, focal lesions were found in 3 optic nerves and remyelination in 2. In the 2 subjects with relapse, VEP at 42 dpi were more delayed and demyelination more evident with only partial or no remyelination. In the single rat where the disease developed in a single acute insult and full recovery, the ensuing remyelination was more represented, bilateral and homogeneous although with thinner myelin. Percent demyelination was correlated with VEPs latency performed at the corresponding time point (r=0,593; p= 0,025). These data are consistent with the view that VEP latencies provide a tool for detecting, measuring and monitoring the extent of demyelination and remyelination in EAE, in a non invasive and quantitative manner allowing to reduce sample size in drug testing and to provide information on the underlying pathological mechanisms.
Disclosure: Silvia Marenna:nothing to disclose
Valerio Castoldi: nothing to disclose
Roberto Santangelo:nothing to disclose
Linda Chaabane:nothing to disclose
Angelo Quattrini:nothing to disclose
Giancarlo Comi:nothing to disclose
Letizia Leocani:nothing to disclose
Abstract: P1096
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Neurophysiology
Remyelination is a rare phenomenon of spontaneous regeneration in the central nervous system and is the response that follows demyelination. Experimental autoimmune encephalomyelitis (EAE) is a good model to study inflammation, demyelination and also the remyelination. Optic nerve involvement and visual evoked potentials (VEPs) have been already shown in EAE model induced with myelin oligodendrocyte glycoprotein (MOG) but not with spinal cord homogenate (SCH), with the potential advantage of a milder chronic-relapsing disease. We measured clinical scores daily and VEPs in 7 DA rats at 0, 7 (n=3), 14, 21, 28, 35 and 42 days post injection (dpi) with optic nerve histology at 28 and 42 dpi. A first attack at 9 dpi, peaking at around 12 dpi with complete to partial recovery, followed by a second attack at 20-23 dpi in two subjects and by full recovery with no further attacks in one. VEPs delay was already evident at 7 dpi and persisted throughout, with the exception of the subject with a single attack and full recovery, which was accompanied by bilateral partial recovery of VEPs latencies. Optic nerves at 28 dpi showed dramatic demyelination consistent with VEPs delays and clinical scores. At 42 dpi, focal lesions were found in 3 optic nerves and remyelination in 2. In the 2 subjects with relapse, VEP at 42 dpi were more delayed and demyelination more evident with only partial or no remyelination. In the single rat where the disease developed in a single acute insult and full recovery, the ensuing remyelination was more represented, bilateral and homogeneous although with thinner myelin. Percent demyelination was correlated with VEPs latency performed at the corresponding time point (r=0,593; p= 0,025). These data are consistent with the view that VEP latencies provide a tool for detecting, measuring and monitoring the extent of demyelination and remyelination in EAE, in a non invasive and quantitative manner allowing to reduce sample size in drug testing and to provide information on the underlying pathological mechanisms.
Disclosure: Silvia Marenna:nothing to disclose
Valerio Castoldi: nothing to disclose
Roberto Santangelo:nothing to disclose
Linda Chaabane:nothing to disclose
Angelo Quattrini:nothing to disclose
Giancarlo Comi:nothing to disclose
Letizia Leocani:nothing to disclose