Osteoporosis is partially caused by dysfunctions in the commitment, differentiation or survival of osteoblasts. Bone marrow fatty acids affect bone resorption and formation. In this study, we aimed to explore the role of fatty acids in the early stages of postmenopausal osteoporosis and determine whether they influence osteogenic differentiation through microRNAs. A quantitative analysis of bone marrow fatty acids early after ovariectomy or sham surgery in a rat osteoporotic model was performed using gas chromatography/mass spectrometry. The results showed that palmitoleate was significantly decreased on postoperative day 3 while both pentadecanoate and palmitoleate were significantly decreased on postoperative day 5 in rats in the ovariectomized group compared with those in the sham group. Palmitoleate promotes osteogenic differentiation, whereas pentadecanoate inhibits this process. Palmitoleate levels were higher than those of pentadecanoate; therefore, the early overall effect of significant bone marrow fatty acid changes was a decrease in osteogenic differentiation. We also found that miR-92b-3p inhibited osteoblastogenesis via the miR-92b-3p/phosphatase and tensin homolog regulatory axis. Palmitoleate, pentadecanoate, and palmitate influenced the osteoblastogenesis of MC3T3-E1 cells through miR-92b-3p. Taken together, we propose that miR-92b-3p mediates the effect of bone marrow fatty acids on osteoblast differentiation in the early stages of osteoporosis. These findings may provide molecular insights for the treatment of osteoporosis.
Purpose: This study aimed to evaluate the underlying mechanisms of decitabine (DAC) in inhibiting acute T-acute lymphoblastic leukemia (T-ALL) cell proliferation and promoting apoptosis.Methods: Human T-ALL cells (CCRF-CEM) were treated with varying concentrations of DAC, and cell proliferation was assessed using a CCK-8 assay. Flow cytometry was used to detect apoptosis and cell cycle alterations. The expression levels of apoptosis-related genes, including PI3K and miR-92b-3p, were quantified using real-time PCR (RT-PCR). Western blotting was used to analyze the expression of apoptotic proteins. Furthermore, we evaluated the in vivo antileukemic activity of DAC using a nude mouse xenograft model, monitored the body weight and tumor volume of mice to calculate inhibition rates, and examined tumor morphological changes in histological sections.Results: DAC significantly inhibited the proliferation of CCRF-CEM cells, accelerated apoptosis, and effectively downregulated the expression of PI3K, AKT, 4EBP1, and mTOR while concurrently upregulating PTEN protein expression. Its regulatory efficacy was markedly enhanced by increasing the dosage. Animal experimental results indicated that both DAC and doxorubicin substantially decreased tumor length, width, volume, and mass; however, DAC demonstrated significantly superior efficacy in inhibiting tumor growth compared to doxorubicin.Conclusion: By selectively targeting the regulation of PTEN and 4EBP1, along with their associated downstream signaling pathways, DAC effectively modulated cellular proliferation, facilitated apoptotic processes, and restrained tumor growth, providing a robust theoretical foundation for clinical treatment strategies in T-ALL.