Contributions
Abstract: P1205
Type: Poster
Abstract Category: Therapy - disease modifying - Neuroprotection
Background: The fumaric acid ester dimethyl fumarate (DMF) is an established disease modifying therapy in multiple sclerosis (MS). DMF exerts neuroprotective effects via induction of the transcription factor “nuclear factor E2-related factor 2” (Nrf2) and detoxification pathways.
Goals: We investigate the role of fumarates on axon growth and regeneration in wild type and Nrf2 knock-out mouse dorsal root ganglia (DRG) model to verify the neuroprotective potential.
Methods: Utilizing DRG explants of wild type and Nrf2 knockout mice, we examine axon regeneration after in vitro transection under the influence of fumarates. We repeat experiments under conditions of oxidative stress. Transferring the techniques into a central nervous system we focus the cortex layer V tissue. Getting an idea of downstream mechanisms of fumarates, we analyse effects on mRNA level using qPCR.
Results: Fumarate treatment, dimethyl fumarate (DMF) and monomethyl fumarate (MMF), promotes axon growth and regeneration.
10µM DMF improved growth cone regeneration of transected DRG axons significantly (p≤0.05) after 4 hours (h) incubation (DMF 52.78 % vs control 24.42%) and 24 h of incubation (DMF 53.37% vs control 26.82%). 5µM MMF treatment resulted in significant higher numbers of growth cones in relation to the number of transected growth cones after all different incubation time-points (4h: MMF 62.3% vs control 36.07%; 24h: MMF 71.14% vs control 39.6%; 48h: MMF 50.66% vs control 33.08%; p≤0.05;).
First analysis under conditions of oxidative stress (500µM H2O2) underlines the neuroprotective potential of fumarates. Regarding current number of n=1 experiment, significances are not obvious by now.
We detected a significant higher expression of NQO-1 (NAD(P)H dehydrogenase quinone 1) as a target gene in downstream pathways in 4h DMF treated DRGs compared to control (p≤0.05). However, mRNA level of the other target genes, named HO-1 (heme oxygenase 1), Nrf2, TXNRD (thioredoxin reductase), Pik3ca (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) and Pi3r4 (phosphoinositide-3- kinase, regulatory subunit 4), was not significantly influenced normed to GAPDH (Glycerinaldehyd-3-phosphat-dehydrogenase).
Conclusion: Fumarate-induced neuroprotection and the knowledge of downstream mechanisms may lead to new treatment options for both inflammatory diseases such as MS and neurodegenerative diseases (e.g. Parkinson"s and Huntington"s disease).
Disclosure: Blusch A: nothing to disclose
Vogelaar CF: nothing to disclose
Nitsch R: nothing to disclose
Gold R: received speakers and consulting honoraria and scientific grant support from Biogen GmbH
Ellrichmann G: received speakers honoraria and scientific grant support from Biogen GmbH
Abstract: P1205
Type: Poster
Abstract Category: Therapy - disease modifying - Neuroprotection
Background: The fumaric acid ester dimethyl fumarate (DMF) is an established disease modifying therapy in multiple sclerosis (MS). DMF exerts neuroprotective effects via induction of the transcription factor “nuclear factor E2-related factor 2” (Nrf2) and detoxification pathways.
Goals: We investigate the role of fumarates on axon growth and regeneration in wild type and Nrf2 knock-out mouse dorsal root ganglia (DRG) model to verify the neuroprotective potential.
Methods: Utilizing DRG explants of wild type and Nrf2 knockout mice, we examine axon regeneration after in vitro transection under the influence of fumarates. We repeat experiments under conditions of oxidative stress. Transferring the techniques into a central nervous system we focus the cortex layer V tissue. Getting an idea of downstream mechanisms of fumarates, we analyse effects on mRNA level using qPCR.
Results: Fumarate treatment, dimethyl fumarate (DMF) and monomethyl fumarate (MMF), promotes axon growth and regeneration.
10µM DMF improved growth cone regeneration of transected DRG axons significantly (p≤0.05) after 4 hours (h) incubation (DMF 52.78 % vs control 24.42%) and 24 h of incubation (DMF 53.37% vs control 26.82%). 5µM MMF treatment resulted in significant higher numbers of growth cones in relation to the number of transected growth cones after all different incubation time-points (4h: MMF 62.3% vs control 36.07%; 24h: MMF 71.14% vs control 39.6%; 48h: MMF 50.66% vs control 33.08%; p≤0.05;).
First analysis under conditions of oxidative stress (500µM H2O2) underlines the neuroprotective potential of fumarates. Regarding current number of n=1 experiment, significances are not obvious by now.
We detected a significant higher expression of NQO-1 (NAD(P)H dehydrogenase quinone 1) as a target gene in downstream pathways in 4h DMF treated DRGs compared to control (p≤0.05). However, mRNA level of the other target genes, named HO-1 (heme oxygenase 1), Nrf2, TXNRD (thioredoxin reductase), Pik3ca (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) and Pi3r4 (phosphoinositide-3- kinase, regulatory subunit 4), was not significantly influenced normed to GAPDH (Glycerinaldehyd-3-phosphat-dehydrogenase).
Conclusion: Fumarate-induced neuroprotection and the knowledge of downstream mechanisms may lead to new treatment options for both inflammatory diseases such as MS and neurodegenerative diseases (e.g. Parkinson"s and Huntington"s disease).
Disclosure: Blusch A: nothing to disclose
Vogelaar CF: nothing to disclose
Nitsch R: nothing to disclose
Gold R: received speakers and consulting honoraria and scientific grant support from Biogen GmbH
Ellrichmann G: received speakers honoraria and scientific grant support from Biogen GmbH