Deletion of mitochondrial anchoring protects dysmyelinating shiverer: implications for progressive MS

Area of Science:

• Neuroscience
• Immunology
• Genetics

Background:

• Multiple sclerosis (MS) involves an early inflammatory phase and a progressive, neurodegenerative phase.
• The mechanisms driving neurodegeneration in progressive MS remain poorly understood.
• The Shiverer mouse model exhibits dysmyelination, sharing similarities with progressive MS.

Purpose of the Study:

• To investigate the role of Syntaphilin (SNPH), a neuron-specific mitochondrial anchoring protein, in a mouse model of progressive MS.
• To determine if genetic deletion of SNPH impacts disease progression and outcomes.
• To explore SNPH's potential as a therapeutic target for progressive MS.

Main Methods:

• Identified parallelisms between progressive MS and the Shiverer mouse model.
• Genetically deleted the Syntaphilin (SNPH) gene in the Shiverer mouse model.
• Assessed the effects of SNPH deletion on survival, cerebellar damage, oxidative stress, and mitochondrial health.
• Evaluated SNPH deletion's impact on the experimental autoimmune encephalomyelitis (EAE) model of early-phase MS.

Main Results:

• SNPH deletion significantly prolonged survival and reduced cerebellar damage in Shiverer mice.
• Deletion of SNPH suppressed oxidative stress and improved mitochondrial health in the Shiverer model.
• Conversely, SNPH deletion did not improve clinical symptoms in the EAE model, suggesting specificity.
• These findings contrast with prevailing evidence suggesting SNPH deletion is detrimental in demyelination.

Conclusions:

• Mitochondrial anchoring by SNPH plays a detrimental role in the progression of demyelinating diseases like MS.
• Targeting mitochondrial anchoring through SNPH deletion presents a novel and specific therapeutic strategy for progressive MS.
• The differential effects of SNPH deletion in Shiverer versus EAE models highlight its specific relevance to the neurodegenerative phase of MS.