Sodium Selenite Promotes Osteoblast Differentiation via The WNT/ß-Catenin Signaling Pathway

Objectives: Osteoporosis is regarded as a silent disorder affecting bone slowly, leading to an increased risk of fractures. Lately, selenium has been found to be associated with the acquisition and maintenance of bone health by affecting the bone remodeling process. However, the mechanism of action of selenium on bone is poorly understood. Here, the objective of this study is to examine the protective effects and mechanism of sodium selenite on the differentiation process of osteoblasts as well as under oxidative stress-induced conditions by evaluating the expression of osteoblast differentiation markers in the sodium selenite and/or hydrogen peroxide (H O-2(2))-treated MC3T3-E1 cell line. Materials and Methods: In this experimental study, we confirmed the inducible osteogenic effect of sodium selenite on MC3T3-E1 cells. Moreover, we investigated the recovery of expression levels of osteogenic markers of sodium selenite in H2O2-treated MC3T3-E1 cells. Results: It was observed that sodium selenite could promote alkaline phosphatase (ALP) activity and collagen synthesis in pre-osteoblasts. Also, sodium selenite enhanced the mRNA expression levels of osteogenic transcriptional factors, like osterix (OSX) and runt-related transcription factor 2 (Runx2). In addition, the terminal differentiation markers, such as osteocalcin (OCN) and collagen 1a (Col1 alpha) were also increased after the treatment of sodium selenite. Also treatment of sodium selenite recused the H2O2-induced inhibition of osteoblastic differentiation of pre-osteoblasts cells via the WNT signaling pathway, implicating its antioxidant activity. Furthermore, sodium selenite restored the H(2)O(2)repressed ss-catenin stability and axin-2 reporter activity in MC3T3-E1 cells. Conclusion: It may be concluded that sodium selenite can stimulate bone formation and rescue the oxidative repression of osteogenesis by activating WNT signaling pathways. Further detailed studies on the role of selenium and its ability to stimulate bone formation via the WNT signaling pathway may project it as a potential therapeutic intervention for osteoporosis.