Rett syndrome, one of the most common causes of intellectual disability related to genetic conditions, affects the way the brain develops. This leads to a progressive inability to use muscles for eye and body movements and speech. It occurs almost exclusively in girls. Currently, there’s no cure for Rett syndrome and treatment focuses on the management of symptoms, including epileptic and respiratory crises.
A team of researchers, partially supported by the EU-funded DISCHROM project, demonstrated how a specific inhibitor can alleviate the clinical symptoms of Rett syndrome. The study was recently published in the ‘Cell Reports’ journal. Dr Manel Esteller, who led the study, explained the findings in a press release by the Bellvitge Biomedical Research Institute. “We knew for some years that the brains of Rett syndrome girls were inflamed, so we decided to test whether a drug that inhibits a central neuroinflammatory protein called glycogen synthase kinase-3B (GSK3B) could reverse part of the symptoms.”
The researchers started with a preclinical model of the disease, studying it in mice that have the same methyl CpG binding protein 2 (MECP2) deficiency as in human Rett syndrome. Classic Rett syndrome and some variant forms of the condition are caused by mutations in the MECP2 gene. This gene provides instructions for making a MeCP2 protein that is critical for normal brain function. Dr Esteller added: “The results have been very promising; agent SB216763 has been able to lengthen the life of the animals, significantly reducing tremors, breathing difficulties and mobility limitations.”
According to the results, “the inhibition of GSK3B also causes an ‘awakening’ of the sleeping neurons of the syndrome: these brain cells are now beginning to regain contact between them and communication between neuronal synapses increases.” Dr Esteller said the findings “provide a new way of improving the quality of life of these patients and now it’s the neurologists’ job to demonstrate their applicability in patients with Rett Syndrome.”
Rett syndrome was one of the chromatin diseases (CD) covered by the DISCHROM project. Chromatin is a complex of macromolecules found in cells, consisting of DNA, protein and ribonucleic acid. Chromatin structure is crucial for regulating gene expression. Several human genetic diseases have been found to be caused by mutations in genes producing proteins involved in maintaining or modifying chromatin structure.
The scope of DISCHROM (Chromatin diseases: from basic mechanisms to therapy) was to promote research and training in the field of CD. For this purpose, the DISCHROM Initial Training Network assembled a group of cross-disciplinary experts who were supported by technology teams. Young researchers were trained at high levels of molecular, cellular, developmental and chromatin biology, genomics, epigenetics, bioinformatics, imaging and high-throughput gene technologies. In addition to Rett syndrome, three other chromatin pathologies were addressed by DISCHROM: alpha thalassemia with mental retardation syndrome; facioscapulohumeral muscular dystrophy; and immunodeficiency, centromeric region instability, facial anomalies syndrome.
For more information, please see:DISHCROM project