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Suarez-Calvet, X.

Publications and source records attributed to Suarez-Calvet, X..

2 recordsLinked to original sources

Decoding Duchenne muscular dystrophy transcriptome to single nuclei level reveals clinical-genetic correlations

The cellular and molecular consequences of lack of dystrophin in humans are only partially known, which is crucial for the development of new therapies aiming to slow or stop the progression Duchenne and Becker muscular dystrophies. We analyzed muscle biopsies of DMD patients and controls using single nuclei RNA sequencing (snRNAseq) and correlated the results with clinical data. DMD samples displayed an increase in regenerative fibers, satellite cells and fibro-adipogenic progenitor cells (FAPs) and a decrease in slow fibers and smooth muscle cells. Samples from patients with stable mild weakness were characterized by an increase in regenerative fibers, while those from patients with progressive weakness had fewer muscle fibers and increased FAPs. DMD muscle fibers displayed a strong regenerative signature, while DMD FAPs upregulated genes producing extracellular matrix and molecules involved in several signaling pathways. An analysis of intercellular communication profile identified FAPs as a key regulator of cell signaling in DMD samples. We show significant differences in the gene expression profiled of the different cell populations present in DMD muscle samples compared to controls.

bioinformatics↗

RhoA/ROCK2 signalling is enhanced by PDGF-AA in fibro-adipogenic progenitor cells in DMD

The lack of dystrophin expression in Duchenne muscular dystrophy (DMD) leads to muscle necrosis and replacement of muscle tissue by fibro-adipose tissue. Although the role of some growth factors in the process of fibrogenesis has been previously studied, the pathways that are activated by PDGF-AA in muscular dystrophies have not been described so far. Herein we report the effects of PDGF-AA on the fibrotic process in muscular dystrophies by performing a quantitative proteomic study in DMD isolated fibro-adipogenic precursor cells (FAPs) treated with PDGF-AA. In vitro studies showed that RhoA/ROCK2 pathway is activated by PDGF-AA and induces the activation of FAPs. The inhibition of RhoA/ROCK signalling pathway by C3-exoenzyme or fasudil attenuated the effects of PDGF-AA. The blocking effects of RhoA/ROCK pathway were analysed in the dba/2J-mdx murine model with fasudil. Grip strength test showed an improvement in the muscle function and histological studies demonstrated reduction of the fibrotic area. Our results suggest that blockade of RhoA/ROCK could attenuate the activation of FAPs and could be considered a potential therapeutic approach for muscular dystrophies.

molecular biology↗