Electrospun fibers have demonstrated a remarkable potential as a framework structure in the fabrication of cartilage tissue engineering (CTE) scaffolds. Various extracellular matrices have been incorporated into electrospun scaffolds to mimic and simulate the extracellular environment. The objective of this study was to fabricate hybrid constructs using composite electrospun scaffolds based on poly (ε-caprolactone) (PCL) and cartilage-derived matrix (CDM) and fibrin hydrogel to improve the viability and differentiation of human adipose-derived stromal cells (ADSCs) for CTE applications.Initially, PCL and PCL-CDM electrospun mats were fabricated. Fibrin/ ADSCs hydrogel were seeded on PCL- CDM mats and arranged layer-by-layer using sandwich technique. This method has been employed to increase cell seeding and infiltration efficiency through the entire mass of the scaffold. Real-time reverse-transcription polymerase chain reaction (RT- PCR), were performed to examine the expression of collagen types II and X, SOX9 and aggrecan. The production of glycosaminoglycan (GAG) was also tested in vitro by Toluidine blue stain and biochemical assay in the cultured scaffolds.The findings demonstrated that incorporation of CDM in PCL fibers results in improved cell viability. Hematoxylin and eosin staining showed that the sandwich method resulted in homogenous cell seeding within the scaffold. Overall, the RT- PCR, biochemical and histological results, showed that incorporation of the CDM into PCL/fibrin sandwich scaffolds stimulated ADSCs chondrogenesis and produced the products which increased expression of chondrogenic genes. It also, enhanced GAG synthesis compared to PCL/fibrin scaffolds.These findings suggest PCL-CDM/fibrin can be considered as an appropriate hybrid scaffold for CTE applications.

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The application of neuroprotective agents in combination with stem cells, is considered as a potential effective treatment for Multiple sclerosis (MS). So, the effects of lithium chloride as a neuroprotective agent and a GSK3-β inhibitor was evaluated in combination with human adipose derived stem cells on re-myelination, oligodendrocyte differentiation, as well as functional recovery. After inducing mouse model of MS and proving it through hanging wire test, the mice were randomly assigned to five experimental groups including: Cup, Sham, Li, hADSC, and Li + hADSC groups. In addition, a control group with normal feeding was considered. At the end, toluidine blue staining was done to estimate the level of myelination. Moreover, Immunofluorescent staining was used to evaluate the mean of OLIG2 and MOG positive cells. Also, the mRNA levels of β-Catenin, myelin and oligodendrocyte specific genes were determined via Real Time-PCR. The results of hanging wire test and toluidine blue staining showed a significant increase in myelin density and motor function improvement in groups which received lithium and stem cells, especially in Li + hADSC group compared to untreated groups (P < 0.01). In addition, immunostaining results indicated that the mean percentage of MOG and OLIG2 positive cells were significantly higher in Li + hADSC group in compared to other groups (P < 0.01). Finally, gene expression studies showed that the use of lithium can able to increase the expression of β-Catenin, myelin and oligodendrocyte specific genes. The use of Lithium Chloride can able to increase stem cells differentiation into oligodendrocytes and improve re-myelination in MS.