Effect of 1, 25-dihydroxy vitamin D3 combined with mechanical strain treatment on proliferation, differentiation, and expression of OPG and RANKL in osteoblastic MC3T3-E1 cells / 医用生物力学

Objective To investigate the effect of 1,25-(OH)2-vitamin D3 (VD3) or mechanical strain alone and their combined treatment on proliferation and differentiation of pre-osteoblast MC3T3-E1 cells in vitro, as well as gene and protein expression of osteoprotegerin (OPG) and receptor activator of nuclear factor-кB ligand (RANKL) in those cells. Methods MC3T3-E1 cells were treated with 10 nmol/L VD3, intermitted mechanical strain or with a combination of these two factors. Cell proliferation was assessed with flow cytometry, and alkaline phosphatase (ALP) activity was measured using a fluorometric detection kit. The mRNA expression of ALP, runt-related transcriptional factor 2 (Runx2), OPG, and RANKL genes was determined by real-time PCR. The proteins expression of Runx2, OPG, and RANKL was determined by Western blotting. ResultsVD3 inhibited the proliferation of MC3T3-E1 cells, but the mechanical strain had no effect on cell proliferation. Mechanical strain, VD3, and the combined treatment enhanced the ALP activity of MC3T3-E1 cells as well as the protein expression of Runx2. The effect of combined treatment was less pronounced than the effect of VD3 or mechanical strain alone. Mechanical strain promoted the gene and protein expression of osteoprotegerin (OPG) and increased the ratio of OPG/RANKL. However, the combination of VD3 and mechanical strain led to a decrease in ratio of OPG/RANKL. Conclusions Mechanical strain might be effective in inducing osteogenic differentiation and increasing bone formation. A joint stimulation with VD3 and strain can decrease proliferation and osteogenic differentiation and increase RANKL expression, which might affect bone remodeling. This study supplies some new data, which might be important in theoretical and clinical research of osteoporosis (OP) and other related bone diseases.

Effect of Wen-Yang Jie-Du Hua-Yu Granules on TLR4 and NF-кB Expression of Rat Hepatic Failure Model with Intestinal Endotoxemia / 世界科学技术-中医药现代化

phological changes in rat liver tissues. TLR4 and NF-κB expression in the liver tissues were measured by im-munohistochemistry . The results showed that compared with the normal group , the serum levels of transaminase ( ALT , AST ) and endotoxin of the model group were higher ( P < 0 . 01 ); and the degree of liver pathology injury was significantly increased; the TLR4 and NF-кB expression were increased (P < 0.01). Compared with the model group, the serum levels of transaminase (ALT, AST) and endotoxin of the experimental group were lower (P < 0.01), the degree of liver pathology injury was significantly lighter; the TLR4 and NF-кB expression were significantly lower (P < 0.01). It was concluded that the WYJDHY granules has a good role in the prevention and treatment of liver injury of rat model of hepatic failure IETM through the downregulation of liver expression of TLR4 and NF-кB in rat liver tissues , reducing serum levels of endotoxin , which may be one of the mecha-nisms on hepatic failure treatment .