Nebbioso, A. | Search bioRxiv

bioRxiv2026

Vorinostat (SAHA) alters the skeletal muscle differentiation program

Epigenetic regulation, particularly histone acetylation, plays a critical role in skeletal muscle differentiation by modulating gene expression programs without altering DNA sequence. Histone deacetylases (HDACs) tightly regulate myogenesis by controlling the timing of differentiation. Pharmacological inhibition of HDACs has shown context-dependent effects on muscle cells. We investigated the effects of 1 {micro}M SAHA (suberoylanilide hydroxamic acid) on C2C12 and L6 myoblasts during differentiation using morphological, immunofluorescence, transcriptomic, and proteomic analyses. SAHA delayed early differentiation, reducing myotube formation with partial recovery at later stages. Transcriptomic analysis revealed time-dependent changes in pathways related to cytoskeleton, cell cycle, and chromatin regulation. Proteomics showed increased mitochondrial metabolism and reduced cytoskeletal components in C2C12 cells, while L6 cells displayed alterations in muscle structural and extracellular matrix proteins. SAHA induces stage- and model-dependent reprogramming of myogenesis, highlighting the importance of timing and cellular context in HDAC-targeted therapies.

cell biology↗

bioRxiv2024

The inhibitory effects of Remodelin on murine myoblasts differentiation

Myoblasts differentiation is a highly regulated and complex process leading to the formation of fused and aligned mature myotubes. Growing interest in the role of epigenetics in muscle differentiation has highlighted epi-modulators as crucial regulators of this process. Our in vitro study aimed to explore the potential effects of the inhibition of the acetyltransferase Nat10 on myoblasts differentiation, by using Remodelin, a Nat10 selective inhibitor. We cultivated and differentiated murine C2C12 myoblasts on ultra-compliant gelatin substrates for up to 16 days and treated them with Remodelin. A combination of morphological analyses, confocal microscopy, transcriptomic profiling (RNA-seq), quantitative proteomics and metabolomics analyses was employed to assess the impact of Nat10 inhibition on myotube formation and maturation. To evaluate the reproducibility of Remodelin effects across myogenic systems and species, L6 rat myoblasts were included as a secondary comparative model. Remodelin treatment impaired myotube organization, alignment, and structural maturation in both C2C12 and L6 cells compared to untreated controls. In C2C12 cultures, Remodelin also abolished spontaneous myotube contractility. Intersection of transcriptomics and proteomics analyses confirmed that Remodelin effectively slowed myotube formation. Overall, these results indicate that Remodelin broadly affects the regulatory networks involved in skeletal muscle differentiation.

cell biology↗