ABSTRACT
BACKGROUND:Cirrhosis is a long-term consequence of chronic hepatic injury, which has no effective therapy. Mesenchymal stem cels have been shown to play a potential role in the treatment of liver fibrosis/cirrhosis. OBJECTIVE:To investigate the therapeutic effect and mechanism of human umbilical cord-derived mesenchymal stem cels on CCl4 induced liver fibrosis/cirrhosis in rats. METHODS:A CCl4-induced liver fibrotic/cirrhotic rat model was used, and human umbilical cord-derived mesenchymal stem cels were injectedvia the tail vein after modeling. Liver biochemical profile was measured by Beckman Coulter analyzer. Histopathological changes were assessed by Sirius red staining. The expressions of colagen type I, colagen type III, matrix metaloproteinases-2 and tissue inhibitor of matrix metaloproteinases-2 protein and mRNA in liver tissues were observed by immunohistochemistry, western blot and real-time PCR, respectively. RESULTS AND CONCLUSION:Liver biochemical profile indicated the transplantation of human umbilical cord-derived mesenchymal stem cels could improve the liver function of rats with liver fibrosis and cirrhosis. After cel transplantation, except 1-week cel transplantation group, the expressions of the matrix metaloproteinases-2 mRNA and protein were significantly increased, while the expressions of colagen type I, colagen type III and tissue inhibitor of matrix metaloproteinases-2 mRNA and protein significantly decreased, compared with the corresponding model groups. Human umbilical cord-derived mesenchymal stem cels play a role in the treatment of liver fibrosis and cirrhosis through upregulating the expression of matrix metaloproteinases-2 and lowering the expression of inhibitor of matrix metaloproteinases-2. With the continued presence of pathogenic factors, human umbilical cord-derived mesenchymal stem cel transplantation cannot reverse liver fibrosis or cirrhosis, and only delay the process of liver fibrosis or cirrhosis.
ABSTRACT
BACKGROUND:Articular chondrocytes with the ability of autocrine and paracrine can provide the growth factors and microenvironment for synovial mesenchymal stem cels differentiating into the chondrocyte. The three-dimensional scaffold could provide space for cels adhesion, proliferation and differentiation. OBJECTIVE: To study the ability of chondrogenesis by co-culturing synovial mesenchymal stem cels and chondrocytes under the three-dimensional condition. METHODS:The synovial membrane and articular cartilage were harvested from rat knee joint. The synovial mesenchymal stem cels and chondrocytes were obtained through the method of enzyme digestion. The passage 3 synovial mesenchymal stem cels and passage 2 chondrocytes were co-cultured in the chitosan/I colagen composite scaffolds at the ratio of 1:2. Then, the cels/scaffold composite was harvested to be examined morphologicaly, histologicaly and immunohistochemicaly after being cultured 21 days. The confocal laser was also employed to detect the cels distribution in the scaffold. RESULTS AND CONCLUSION: After being cultured 72 hours, it could be observed from the cels/scaffold composite examined through the scanning electron microscope that the cels adhered on the surface of the scaffold and extracelular matrix surrounding the cels was seen on the scaffold. After being cultured 21 days, it could be found through the confocal laser scanning that the cels were wel-distributed on the scaffold, and cels decreased gradualy. Type II colagen was positive in the extracelular matrix immunohistochamicaly. It suggested from this study that the synovial mesenchymal stem cels could be co-cultured with chondrocytes in the chitosan/I colagen composite scaffolds and have the ability of chondrogenesis differentiation.
ABSTRACT
BACKGROUND:Low toxicity of Genipin has certain species and cellspecificity. Biocompatibility of Genipin cross-linked type I colagen with human adipose-derived stem cels is essential for construction of tissue-engineered adipose. OBJECTIVE:To investigate the bbiocompatibility of Genipin cross-linked type I colagen with human adipose-derived stem cels. METHODS:Human adipose-derived stem cels were isolated and cultured to the third generation, and the cels were seeded on Genipin cross-linked type I colagen scaffold. MTT assay was used to evaluate the adhesion and proliferation of cels on the scaffold, and the toxic effects of Genipin cross-linked type I colagen on human adipose-derived stem cels. Optical microscopy and scanning electron microscopy were utilized to observe the adhesion and growth process of human adipose-derived stem cels on the scaffold as wel as the morphological changes of cels. RESULTS AND CONCLUSION:Human adipose-derived stem cels could adhere to the scaffold immediately after seeded and increase gradualy on the scaffold, with the average adhesion rate of 86.5%. Optical microscopy and scanning electron microscopy showed that human adipose-derived stem cels adhered wel on the scaffold. The cels increased gradualy over time, and could migrate into the scaffold, and distribute evenly with the passage of time when observed with optical microscopy. The result showed Genipin possesses very low cytotoxicity to the cels, and the outstanding biocompatibility is found between the cels and scaffoldin vitro after cross-linked with Genipin.