Bio-functionalized hydrogel patches of chitosan for the functional recovery of infarcted myocardial tissue.

The aim of this work was to assess the potential benefits of the enrichment of a chitosan hydrogel patch with secretome and its epicardial implantation in a murine model of chronic ischemia, focusing on the potential to restore the functional capacity of the heart. Thus, a hydrogel with a final polymer concentration of 3 % was prepared from chitosan with an acetylation degree of 24 % and then bio-functionalized with a secretome produced by mesenchymal stromal cells. The identification of proteins in the secretomes showed the presence of several proteins known to have beneficial effects on cardiac muscle repair.

Generation of human induced pluripotent stem cell lines from five patients with Myofibrillar myopathy carrying different heterozygous mutations in the DES gene.

Myofibrillar myopathy (MFM) is a rare genetic disorder characterized by muscular dystrophy that is often associated with cardiac disease. This disease is caused by mutations in several genes, among them DES (encoding desmin) is the most frequently affected. Peripheral blood mononuclear cells from 5 different MFM patients with different DES mutations were reprogrammed into induced pluripotent stem cells (IPSC) using non-integrative vectors.

Anisotropic dense collagen hydrogels with two ranges of porosity to mimic the skeletal muscle extracellular matrix.

Despite the crucial role of the extracellular matrix (ECM) in the organotypic organization and function of skeletal muscles, most 3D models do not mimic its specific characteristics, namely its biochemical composition, stiffness, anisotropy, and porosity. Here, a novel 3D in vitro model of muscle ECM was developed reproducing these four crucial characteristics of the native ECM. An anisotropic hydrogel mimicking the muscle fascia was obtained thanks to unidirectional 3D printing of dense collagen with aligned collagen fibrils.

Vimentin: Regulation and pathogenesis.

Vimentin, an abundant cytoplasmic intermediate filament protein, is recognized for its important role in stabilizing intracellular structure. Vimentin has been recognized for its mechanical role in cell plasticity and stress absorbers. Additionally, the functions of vimentin, similar to all other cytoplasmic intermediate filaments, are correlated to its ability to interact with cellular components responsible for signaling as well as kinases, therefore exerting control on gene regulatory networks.

Efficacy of epicardial implantation of acellular chitosan hydrogels in ischemic and nonischemic heart failure: impact of the acetylation degree of chitosan.

This work explores the epicardial implantation of acellular chitosan hydrogels in two murine models of cardiomyopathy, focusing on their potential to restore the functional capacity of the heart. Different chitosan hydrogels were generated using polymers of four degrees of acetylation, ranging from 2.5% to 38%, because the degree of acetylation affects their degradation and biological activity.