RESUMO
BACKGROUND: Mesenchymal stem cells (MSCs) have been explored as promising tools for treatment of several neurological and neurodegenerative diseases. MSCs release abundant extracellular vesicles (EVs) containing a variety of biomolecules, including mRNAs, miRNAs, and proteins. We hypothesized that EVs derived from human Wharton's jelly would act as mediators of the communication between hMSCs and neurons and could protect hippocampal neurons from damage induced by Alzheimer's disease-linked amyloid beta oligomers (AßOs). METHODS: We isolated and characterized EVs released by human Wharton's jelly mesenchymal stem cells (hMSC-EVs). The neuroprotective action of hMSC-EVs was investigated in primary hippocampal cultures exposed to AßOs. RESULTS: hMSC-EVs were internalized by hippocampal cells in culture, and this was enhanced in the presence of AßOs in the medium. hMSC-EVs protected hippocampal neurons from oxidative stress and synapse damage induced by AßOs. Neuroprotection by hMSC-EVs was mediated by catalase and was abolished in the presence of the catalase inhibitor, aminotriazole. CONCLUSIONS: hMSC-EVs protected hippocampal neurons from damage induced by AßOs, and this was related to the transfer of enzymatically active catalase contained in EVs. Results suggest that hMSC-EVs should be further explored as a cell-free therapeutic approach to prevent neuronal damage in Alzheimer's disease.
Assuntos
Peptídeos beta-Amiloides/toxicidade , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/citologia , Neurônios/patologia , Neuroproteção , Estresse Oxidativo , Sinapses/patologia , Geleia de Wharton/citologia , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Exossomos/metabolismo , Exossomos/ultraestrutura , Vesículas Extracelulares/efeitos dos fármacos , Vesículas Extracelulares/ultraestrutura , Hipocampo/patologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Multimerização Proteica , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sinapses/efeitos dos fármacosRESUMO
Cartilage tissue has a poor capacity for self-repair, especially in the case of severe cartilage damage due to trauma or age-related degeneration. Cell-based tissue engineering using scaffolds has provided an option for the repair of cartilage tissue. The present work demonstrates that a three-dimensional (3D) chitosan scaffold increases the efficiency of the adhesion and differentiation of mesenchymal stem cells (MSCs) after the addition of a chondrogenic medium. These culture conditions promoted MSC differentiation into chondrocytes during the first 9 weeks of monolayer or 3D culture in a scaffold composed of chitosan or chitosan/gelatin. The results demonstrated that a chitosan scaffold caused a reduction in alkaline phosphatase production and an increase in the collagen concentration indicating phenotypic changes in the cells. In support of these results, the production of collagen type II by the MSCs cultured in the chitosan scaffold increased after 3 weeks of culture, indicating the beginning of differentiation. However, the addition of gelatin to the chitosan scaffold did not improve on the results obtained with chitosan alone. These results suggest that this 3D chitosan scaffold is a promising candidate for biomaterial implants designed to promote MSC colonization and has applications in regenerative medicine.