Rationale: The Myocyte Enhancer Factor-2 (MEF2) family of transcription factors represents an interesting candidate of study for ALS, since playing a major role in muscle and neural development and maintenance, besides sustaining the immune response in blood mononuclear cells (PBMC). We recently reported the increase of MEF2C and MEF2D mRNA in PBMC of sporadic and SOD1+ ALS patients, showing preliminary data on the association between the fold-change of these targets and disease progression rate.
Broad objectives: ALS is a relentless disorder expressing elevated heterogeneity in terms of individual progression. The general aim of this project is to tackle the still largely unknown biological determinants underlying such variability. Considering our preliminary data, we specifically candidate for this pilot project the assessment of MEF2C and MEF2D fold-change over time as putative biomarkers for predicting ALS progression rate. At the same time, a study in different ALS models will allow to understand the regulatory mechanisms involved in ALS-associated MEF2 alterations.
Project design and methods: This is a pilot longitudinal study (6 months) on 30 ALS patients, assessing the expression of MEF2 isoform mRNA in PBMC by real-time PCR; patients will be deeply phenotyped for carefully estimating progression rate. 15 healthy controls will be recruited as well for confirming previous results. In a subset of samples, H3 acetylation and K27 trimethylation within the MEF2 promoter region will be assessed by ChIP assay for discovering the regulatory dynam ics of our targets. During recruitment, cell culture experiments (NSC34 overexpressing SOD1-G93A) will be performed modulating MEF2 isoform expression (siRNA and epigenetic drugs), in order to further study the involved mechanisms and any putative downstream ALS-related phenotype (eg., apopotosis, etc.). Finally, MEF2 isoform expression will be assessed in PBMC, spinal cord and muscles of two types of symptom atic SOD1-G93A mice expressing discernible differences in motor neuron disease onset and progression.