The effect of cerebrospinal fluid-derived exosomes on neural differentiation of adipose mesenchymal stem cells in alginate hydrogel scaffold

Nowadays, researchers have made extensive efforts to find new treatments for nerve damage. Meanwhile, the role of exosomes in cell-cell communication is considered to be a new mechanism. Exosomes can act as suitable differentiating agents. The aim of this study was to investigate the differentiating effect of cerebrospinal fluid-derived exosomes on adipose mesenchymal stem cells in alginate hydrogel. Exosomes were extracted from the cerebrospinal fluid by ultracentrifugation and were then identified by atomic force microscopy (AFM), SEM and DLS technique. In addition, Adipose Mesenchymal Stem cells in alginate hydrogel were treated with different concentrations of exosomes. Cell survival was assessed by MTT and Acridine Orange/Ethidium Bromide methods. Cell differentiation was processed by immunocytochemistry and Real-Time PCR. Examinations confirmed the presence of exosomes with an approximate size of 70 nm. Cell survival results indicate that he ability of cells to survive and proliferate during 14 days. Also, the expression of MAP2 proteins (microtubule-associated protein 2) and Nestin (intermediate filament protein) was confirmed by immunocytochemistry. The results of Real Time - PCR showed that during the seventh and fourteenth days the expression level of MAP2 gene increased and the expression of Nestin gene showed a significant decrease compared to the control group. This study showed that exosomes extracted from cerebrospinal fluid can cause neuronal differentiation of Adipose mesenchymal stem cells in alginate hydrogel scaffolds.