ABSTRACT
Background: Osteoarthritis is one of the most common diseases in middle-aged populations in the World and could become the fourth principal cause of disability by the year 2020. One of the critical properties for cartilage tissue engineering [TE] is the ability of scaffolds to closely mimic the extracellular matrix and bond to the host tissue. Therefore, TE has been presented as a technique to introduce the best combination of cells and biomaterial scaffold and to stimulate growth factors to produce a cartilage tissue resembling natural articular cartilage. The aim of study is to improve differentiation of adipose derived stem cells [ADSCs] into chondrocytes in order to provide a safe and modern treatment for patients suffering from cartilage damages
Methods: After functionalization, dispersions and sterilizing carbon nano-tubes [CNTs], a new type of nanocomposite gel was prepared from water-soluble CNTs and alginate. ADSCs seeded in 1.5% alginate scaffold and cultured in chondrogenic media with and without transforming growth factor-beta1 [TGF-beta1] for 7 and 14 days. The genes expression of sex determining region Y-box 9 [SOX9], types II and X collagens was assessed by real-time polymerase chain reaction and the amount of aggrecan [AGC] and type I collagen was measured by ELISA
Results: Our findings showed that the expression of essential cartilage markers, SOX9, type II collagen and AGC, in differentiated ADSCs at the concentration of 1 microg/ml CNTs in the presence of TGF-beta1 were significantly increased in comparison with the control group [P < 0.001]. Meanwhile, type X collagen expression and also type I collagen production were significantly decreased [P < 0.001]
Conclusions: The results showed that utilized three-dimensional scaffold had a brilliant effect in promoting gene expression of chondrogenesis
ABSTRACT
Sirtuin1 is an enzyme that deacetylates histones and several non-histone proteins including P53 during the stress. P300 is a member of the histone acetyl transferase family and enzyme that acetylates histones. Hereby, this study describes the potency combination of Salermide as a Sirtuin1 inhibitor and cholera toxin B [CTB] as a P300 activator to induce apoptosis Michigan Cancer Foundation-7 [MCF-7] and MRC-5. Cells were cultured and treated with a combination of Salermide and CTB respectively at concentrations of 80.56 and 85.43 micro mol/L based on inhibitory concentration 50 indexes at different times. The percentage of apoptotic cells were measured by flow cytometry. Real-time polymerase chain reaction was performed to estimate the messenger ribonucleic acid expression of Sirtuin1 and P300 in cells. Enzyme linked immunosorbent assay and Bradford protein techniques were used to detect the endogenous levels of total and acetylated P53 protein generated in both cell lines. Our findings indicated that the combination of two drugs could effectively induced apoptosis in MCF-7 significantly higher than MRC-5. We showed that expression of Sirtuin1 and P300 was dramatically down-regulated with increasing time by the combination of Salermide and CTB treatment in MCF-7, but not MRC-5. The acetylated and total P53 protein levels were increased more in MCF-7 than MRC-5 with incubated combination of drugs at different times. Combination of CTB and Salermide in 72 h through decreasing expression of Sirtuin1 and P300 genes induced acetylation of P53 protein and consequently showed the most apoptosis in MCF-7 cells, but it could be well-tolerated in MRC-5. Therefore, combination of drugs could be used as an anticancer agent