TOXICITY IN MND

Screening of candidate targets for astrocytic toxicity in motor neurone disease

 Partecipanti

Mappa

 Word cloud

Esplora la "nuvola delle parole (Word Cloud) per avere un'idea di massima del progetto.

 Obiettivo del progetto (Objective)

'Motor neurone disease (MND) is a neurodegenerative disease, characterized by progressive loss of motor neurons (MN), leading to muscle atrophy and death. Approximately 10% of cases are familial, and 20% of these have been linked to dominant mutations in Cu/Zn superoxide dismutase 1 (SOD1). Transgenic mice carrying mutant SOD1 develop a neuromuscular disease similar to human MND. For nearly a decade MND has been considered a disease selectively affecting the MN, but strong evidence has accumulated over recent years indicating that non-neuronal (glial) cells are significantly involved in the pathogenesis of MND. In the outgoing host laboratory, neural progenitor cells (NPCs) have been successfully isolated from human post-mortem spinal cord and differentiated into astrocytes. It was shown that NPC-derived astrocytes from both sporadic and familial MND cases share a common non-cell autonomous toxicity, selectively killing MN in a co-culture model system. Therefore, these cells can be successfully used to screen the toxic pathways involved in the disease and co-cultures with GFP positive MN produce a reliable readout for this toxicity, providing the only in vitro screening tool for sporadic MND derived from human neuronal tissue. In the present proposal, short hairpin RNA (shRNA) will be used to silence the expression of targeted candidate genes selected from a previous microarray study in order to investigate the factors involved in astrocyte toxicity in MND. The best hits from the in vitro screening will be tested in vivo in the mutant SOD1 mouse model of the disease using adeno-associated virus 9 (AAV9). AAV9 have been shown to have a preferential tropism for adult astrocytes within the central nervous system, which makes them the most appropriate tool to specifically target astrocytes in vivo. During the return phase, the NPC derived astrocytes will be used to screen compounds from a drug library and the new technology will be set up in the host laboratory'

Introduzione (Teaser)

Understanding the molecular aetiology of neurodegeneration is central for the design of novel therapies. European scientists are working in this context to identify therapeutic targets for amyotrophic lateral sclerosis (ALS).

Descrizione progetto (Article)

ALS is characterised by death of upper and lower motor neurons. Patients usually succumb within 2-5 years of diagnosis from respiratory failure.

Accumulating evidence indicates that deletion of superoxide dismutase 1 (SOD1) in motor neurons delays disease onset while depletion from microglia or astrocytes slows down disease progression. The EU-funded TOXICITY IN MND (Screening of candidate targets for astrocytic toxicity in motor neurone disease) project worked on identifying factors that contribute to astrocyte toxicity.

Scientists used RNAi technology to screen candidate gene targets and test their efficacy in dampening astrocyte toxicity in vitro. Genes belonging to or regulating the complement system, inflammation and the immune response were screened alongside cell adhesion genes.

NFkB has emerged as a molecule implicated in astrocyte-mediated toxicity. Researchers also studied oligodendrocytes from ALS patients with mutations in different genes.

In vivo depletion of SOD1 in an ALS mouse model significantly extended animal survival even when the enzyme was deleted after disease onset.

Overall, the TOXICITY IN MND study should help provide potent therapeutic compounds or shed light on pathways that have not been targeted before to treat ALS.