Multiple approaches for Duchenne muscular dystrophy therapy

Exon Skipping has been demonstrated to be a successful strategy for the gene therapy of Duchenne Muscular Dystrophy (DMD): the rational is to convert severe Duchenne forms into milder Becker ones. Here we show the selection of U1 snRNA-antisense constructs able to confer effective rescue of dystrophin synthesis in a Δ44 Duchenne genetic background, through skipping of exon 45; moreover, we demonstrate that the resulting dystrophin is able to recover the correct timing of myogenic marker expression, to re-localize nNOS and to rescue expression of miRNAs previously shown to be sensitive to the Dystrophin-nNOS-HDAC2 pathway. Becker mutations display different phenotypes, likely depending on whether the shorter protein is able to reconstitute the wide range of wild type functions. Among them, efficient assembly of the dystrophin associated protein complex (DAPC) and Nitric Oxide Synthase (nNOS) localization are important. Comparing different Becker deletions we demonstrate the correlation between the ability of the mutant dystrophin to re-localize nNOS and the expression levels of two miRNAs, miR-1 and miR29c, known to be involved in muscle homeostasis and to be controlled by the Dys-nNOS-HDAC2 pathway. Since the gene responsible for the disease has been identified, several aberrant pathways have been characterized and many therapeutic approaches have been proposed to face all the symptoms associated to the pathology. What is now quite clear is that the best way to cure the disease is to apply different strategies in parallel, to enhance the beneficial effect that could be obtained from a single treatment. With this concept in mind we identified a microRNA, miR-31, that is deregulated in DMD conditions if compared to a healthy control. This miRNA represses dystrophin expression by targeting its 3′UTR region. In human DMD myoblasts treated with exon skipping, we demonstrate that miR-31 inhibition increases dystrophin rescue. These results indicate that interfering with miR-31 activity can provide an ameliorating strategy for those DMD therapies that are aimed at efficiently recovering dystrophin synthesis

Novel long noncoding RNAs (lncRNAs) in Myogenesis: A miR-31 overlapping lncRNA transcript controls myoblast differentiation

Transcriptome analysis allowed the identification of new long noncoding RNAs differentially expressed during murine myoblast differentiation. These transcripts were classified on the basis of their expression under proliferating versus differentiated conditions, muscle-restricted activation, and subcellular localization. Several species displayed preferential expression in dystrophic (mdx) versus wild-type muscles, indicating their possible link with regenerative processes. One of the identified transcripts, lnc-31, even if originating from the same nuclear precursor of miR-31, is produced by a pathway mutually exclusive. We show that lnc-31 and its human homologue hsa-lnc-31 are expressed in proliferating myoblasts, where they counteract differentiation. In line with this, both species are more abundant in mdx muscles and in human Duchenne muscular dystrophy (DMD) myoblasts, than in their normal counterparts. Altogether, these data suggest a crucial role for lnc-31 in controlling the differentiation commitment of precursor myoblasts and indicate that its function is maintained in evolution despite the poor sequence conservation with the human counterpart

miRNAs as serum biomarkers for Duchenne muscular dystrophy

Dystrophin absence in Duchenne muscular dystrophy (DMD) causes severe muscle degeneration. We describe that, as consequence of fibre damage, specific muscle-miRNAs are released in to the bloodstream of DMD patients and their levels correlate with the severity of the disease. The same miRNAs are abundant also in the blood of mdx mice and recover to wild-type levels in animals ‘cured’ through exon skipping. Even though creatine kinase (CK) blood levels have been utilized as diagnostic markers of several neuromuscular diseases, including DMD, we demonstrate that they correlate less well with the disease severity. Although the analysis of a larger number of patients should allow to obtain more refined correlations with the different stages of disease progression, we propose that miR-1, miR-133, and miR-206 are new and valuable biomarkers for the diagnosis of DMD and possibly also for monitoring the outcomes of therapeutic interventions in humans. Despite many different DMD therapeutic approaches are now entering clinical trials, a unifying method for assessing the benefit of different treatments is still lacking

Il sito dell’età del Bronzo recente di Oratino – La Rocca (CB)

The paper presents the results of recent investigation at the Bronze age site of Oratino, La Rocca, on the High Biferno Valley. Here has been possible to recognize a portion of several Late Medieval structures and a conspicuous Late Subappenine archaeological deposit. The continuity of occupation form the previous phases is also attested by some potshards decorated with the typical “Appenine” schemes. The authors presents the pottery findings from the East area of the site, where the excavation has brought to light some layers related to domestic activities, as two cooking structures realized in a short time lapse