whartons’ jelly

Activated cells which are called star-shaped cells, are some of the key factors in the development of liver fibrosis. Activation of NADPH oxidase (NOX) is associated with increased HSCs activity and progression of hepatic fibrosis. In this study, the effects of human exosomes derived from WJ-MSCs on NOX1, NOX2, and NOX4 gene expression in TGF-β-induced hepatic fibrosis were investigated.

LX2 cell line was treated with 2 ng/ml TGF-β for 24 hr, in order to induce liver fibrosis after starvation. In the next step, the cells were treated with several concentrations of the exosomes derived from WJ-MSCs (10, 20, 30, 40, and 50 μg/ml). Finally, Smad3C phosphorylated protein expression level and NOX1, NOX2, and NOX4 gene expression levels were measured.

The results demonstrated that the level of NOX1, NOX2, and NOX4 mRNA expressions decreased significantly during 24 hrs at concentrations of 40 and 50 μg/ml of WJ-MSCs exosomes in TGF-β-induced-HSCs. The p-Smad3C proteins were significantly decreased (fold change: 1.83, P-value<0.05) after exposure to WJ-MSC-derived exosomes. 

Treatment with exosomes prevents further activation of HSCs by inhibiting the level of Smad3C phosphorylation. The experimental data of our study suggested that in liver fibrosis, the protection of HSCs activation against TGF-β by inhibiting the NOX pathway via human exosomes of WJ-MSCs is extremely important. It needs further research as a treatment method.

Articular cartilage has a limited potential for self-repairing due to the scarce number of chondrocytes and avascularity. As regards the low proliferative potential of chondrocyte under in vitro conditions, nowadays mesenchymal stem cells are introduced for osteoarthritis (OA) treatment. Accordingly, the present study aimed to evaluate whether co-culture of chondrocytes with 2 different sources of mesenchymal stem cells, namely, adipose and Wharton"s jelly derived can promote the expression of cartilage specific genes by chondrocytes. Mesenchymal stem cells were isolated from both adipose tissue and Wharton"s jelly. The obtained cells were co-cultured with chondrocytes or cultivated alone as control for 3 days. Then, cartilage specific genes including collagen II, Sox9, cartilage oligomeric matrix protein (COMP), and aggrecan were evaluated using the real time Reverse transcription polymerase chain reaction (RT-PCR). The expression of genes in chondrocytes alone was significantly higher compared to the co-culture of chondrocytes with both stem cell types. In addition, the results revealed that co-culture of Wharton jelly derived stem cells (WJSCs) with chondrocyte led to higher expression of genes compared to WJSCs alone. However, the co-culture of the adipose-derived stem cells (ASCs) demonstrated no significant change. Generally, no up-regulation of cartilage specific genes was observed by co-cultivation of chondrocytes with ASCs or WJSCs compared to chondrocytes. Further, stem cells derived from Wharton"s jelly expressed higher levels of the above mentioned genes compared to those of the ASCs.