ABSTRACT
BACKGROUND: Micro-arc oxidation (MAO) treatment can improve the biological properties of titanium alloy implants. Previous studies mostly focused on the evaluation of titanium alloy plate, while the effects of the MAO-modified 3D titanium scaffold on the cell growth and differentiation were rarely reported. OBJECTIVE: To investigate the effect of MAO coating on the biological performance of cells seeded onto the 3D-printed porous titanium alloy scaffold. METHODS: Rat bone marrow mesenchymal stem cells were seeded onto the MAO-modified Ti6Al4V alloy scaffolds (experimental group) and unmodified scaffolds (control group). After 4 and 7 days of culture, cell/scaffold constructs were retrieved and processed for the assessment of cell morphology by using scanning electron microscopy, cytoskeletal staining analysis and cell viability assay were also evaluated. At 4, 7 and 11 days of culture, the levels of alkaline phosphatase and osteocalcin in the cell supernatant were detected. At 1, 4, 7 and 11 days of culture, the cell proliferation rate was measured using the MTT assay. RESULTS AND CONCLUSION: (1) At 4 and 7 days of culture, live/dead staining showed that the bone marrow mesenchymal stem cells grew well on the two kinds of scaffolds. The analysis of cytoskeleton staining showed that the cytoskeleton of the experimental group was stereo and polygonal, while the cells on the scaffold surface in the control group were flat and spindle-shaped, spreading along the macro structure of the scaffolds. Under the scanning electron microscopy, the cells in the experimental group arranged closely and spread in a good condition, with interconnected lamellipodia and filopodia that firmly adhered to the scaffold surface in an anchor-shaped structure; in the control group, less filopodia interconnected, less extracellular matrix, and flat and sheet-like cells were observed. (2) With the time increase, the levels of alkaline phosphatase and osteocalcin increased gradually in both groups. The alkaline phosphatase level in the experimental group was significantly higher than that in the control group at 7 and 11 days of culture (P < 0.05), while the osteocalcin level was higher in the experimental group than the control group at 11 days of culture (P < 0.05). (3) With the prolongation of culture time, the number of cells in the two groups increased gradually. The number of cells cultured in the experimental group was significantly higher than that in the control group at 7 and 11 days of culture (P < 0.05). To conclude, the MAO-modified titanium alloy scaffold is favorable for cell adhesion, proliferation and differentiation.
ABSTRACT
Objective To observe the effects of Jieduan Niwan Prescription on IL-6 and TNF-α in serum and hepatic tissue in acute-on-chronic liver failure rats (ACLF); To study the partial mechanism of the treatment for ACLF. Methods The ACLF rat model was established by using human serum albumin immuno-induced hepatic fibrosis followed with D-galactosamine and lipopolysaccharide joint acute attack. The SPF Wistar male rats were randomly divided into normal group, model group and Jieduan Niwan Prescription group, respectively. The Jieduan Niwan Prescription group was treated by Jieduan Niwan Prescription after the acute attack for 24 h, and the rats were sacrificed respectively at 5, 10 and 15 days after gavage administration. Transmission electron microscope was employed to observe the ultrastructural changes in liver cells and ELISA was used to detect the contents of IL-6 and TNF-α in serum and liver tissue, respectively. Results Compared with the normal group, the contents of serum and liver tissue IL-6 and TNF-α in model group increased at each time point. Compared with the model group, the contents of serum and liver tissue IL-6 and TNF-α decreased in Jieduan Niwan Prescription group, especially in 15 days. Under the transmission electron microscope, the changes of ultrastructure of liver tissue were observed. With the passage of time, the degree of hepatocyte injury in model group gradually increased, but decreased significantly in Jieduan Niwan Prescription group at each time point. Conclusion Jieduan Niwan Prescription can effectively reduce the levels of IL-6 and TNF-α in serum and liver tissue, reduce the degree of liver damage, and has a certain protective effect on the liver.