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Sanggenon C (SC), which is a natural flavonoid found in the stem bark of Cortex Mori, has been discovered to have the antioxidant, anti-inflammatory, and antitumor properties. However, its effect in osteoporosis has not yet been reported. In this research, the effect of SC on the proliferation of MC3T3-E1 cells was evaluated by using the MTT assay. Alkaline phosphatase (ALP) activity and the mRNA expression of Runx2, Collagen I, OPG, and RANKL were examined. TRAP-positive cell counting and bone resorption pits were adopted to observe the effect of SC on the formation and function of osteoclasts. Next, the mRNA level of TRAP, CTSK, NFATc1, and TRAF6 of osteoclasts were measured by real-time qPCR. In addition, the anti-osteoporosis activity of SC in vivo was evaluated in the zebrafish model. Our study indicated that SC exhibited a significant stimulatory effect on MC3T3-E1 cell proliferation at 1 to 10 µM and caused an increase in ALP activity at 0.3 to 10 µM. It could upregulate the expression of Runx2, Collagen I, and increases the OPG/RANKL ratio. Furthermore, SC was found to inhibit the formation and function of osteoclasts, which is demonstrated by a lower number of TRAP-positive multinuclear cells and a fewer area of bone resorption pits compared to the control group. TRAP, CTSK, and NFATc1 were downregulated in 0.3 to 10 µM SC treated groups. In addition, 3 to 10 µM SC also inhibited the expression of TRAF6 mRNA. When prednisone-induced zebrafish was treated with 0.3, 1, 3, and 10 µM SC, higher mineralization of vertebrate column was discovered in a dose-dependent pattern, which suggests that SC could reverse the bone loss of zebrafish caused by prednisone. In summary, these findings indicated that SC has the potential to prevent or treat osteoporosis. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a common cause of functional deterioration in older adults, and altered chondrogenesis is the most common pathophysiological process involved in the development of OA. MicroRNA-145 (miR-145) has been shown to regulate chondrocyte homeostasis. However, the function of miR-145 in OA remains to be elucidated. In the present study, the expression levels of miR-145 were examined in cartilage specimens from 25 patients with knee OA using reverse transcription-quantitative polymerase chain reaction analysis. The effects of miR-145 on the proliferation and fibrosis of the C-20/A4 and CH8 cell lines were also investigated using 3-(4,5-dimethylth-iazol-2-yl)-2,5-diphenyltetrazolium bromide and western blot assays in vitro. The results revealed that the expression of miR-145 was decreased in the OA cartilage tissues, compared with normal cartilage tissues. The overexpression of miR-145 by transfection of cells with miR-145 mimics significantly inhibited C-20/A4 and CH8 cell proliferation and fibrosis. Furthermore, tumor necrosis factor receptor superfamily, member 11b (TNFRSF11B) was identified as a direct target of miR-145 in chondrocytes, which was confirmed using a dual-luciferase reporter assay. The expression level of TNFRSF11B was markedly upregulated in the patients with OA, and the ectopic expression of miR-145 was capable of suppressing the expression of TNFRSF11B. In addition, the knock down of TNFRSF11B using specific small interfering RNA also inhibited the proliferation and fibrosis of C-20/A4 and CH8 cells in vitro. These data provide the first evidence, to the best of our knowledge, to suggest the critical function of miR-145 in regulating the expression of TNFRSF11B, which may have important implications on the regulation of chondrocyte proliferation and fibrosis in OA. [ABSTRACT FROM AUTHOR]

Background and Aim: MicroRNAs are a class of small non-coding RNAs that negatively regulate the expression of their target genes. The aim of the present study was to explore the effects of microRNA on biological behaviors of HepG2 cells and further analyze its characteristics. Methods: We detected different expression profiles of miRNAs in HepG2 and L02 cell lines by microRNA microarray. Northern blot, quantitative real-time polymerase chain reaction, methylthiazolyl tetrazolium, fluorescence-activated cell sorting, scratch wound, transwell migration and Matrigel invasion assays and western blot were carried out to determine whether or not microRNA-224 ( miR-224) can influence the biological behaviors of HepG2 cells. Results: MiR-224 was significantly upregulated in HepG2 cells. Cell proliferation, migration and invasion, but not cell cycles, were altered after changing the expression of miR-224. Taking invasion and migration as a breakthrough, a close relationship between the expression of miR-224 and its proteins such as PAK4 and MMP9, which were involved in the invasion of tumor, was found. Conclusions: Overexpression of miR-224 was involved in the malignant phenotype of HepG2 cells, and it may be an important factor in regulating the migration and invasion of HepG2 cells. [ABSTRACT FROM AUTHOR]