Calycosin stimulates the osteogenic differentiation of rat calvarial osteoblasts by activating the IGF1R/PI3K/Akt signaling pathway

Abstract

Calycosin has been reported to have a strong osteogenic activity and a positive correlation with anti‐osteoporosis effects. However, its precise mechanism of action remains unclear. Since insulin‐like growth factor 1 receptor (IGF1R) signaling and phosphatidylinositol 3‐kinase/Akt (PI3K/Akt) signaling have been shown to play a pivotal role in regulating osteogenesis, we hypothesized that the osteogenic activity of calycosin is mediated by these signaling pathways. Rat calvarial osteoblasts (ROBs) were cultured in osteogenic medium containing calycosin with or without GSK1904529A (GSK) or LY294002 (LY) (inhibitors of IGF1R and PI3K, respectively). The effects on cell proliferation, alkaline phosphatase (ALP) activity, calcified nodules, mRNA or protein expression of osteogenic genes [alkaline phosphatase (Alpl), collagen type I (Col1a1), runt‐related transcription factor 2 (Runx2), Osterix, and bone morphogenetic protein 2 (Bmp2)], and phosphorylation of IGF1R and Akt were examined. The present results showed that calycosin enhanced cell proliferation, ALP activity and Alizarin Red‐S staining in a dose‐dependent manner in the range of 10−8–10−6 M, while an inhibitory effect was observed at 10−5 M. Treatment at the optimal concentration (10−6 M, a physiologically achievable concentration) increased mRNA levels of osteogenic genes and phosphorylation of IGF1R and Akt. Furthermore, treatment with GSK or LY partly reversed the effects of calycosin on ROBs, as indicated by the decreases in calycosin‐induced ALP activity, calcified nodules and osteogenic gene expression. These results suggest that the osteogenic effect of calycosin partly involves the IGF1R/PI3K/Akt signaling pathway.

Gallium ions promote osteoinduction of human and mouse osteoblasts via the TRPM7/Akt signaling pathway

“…Effect of Ga ions on the Akt signaling pathway in osteoblasts. Based on the key roles of the akt signaling pathway in regulating ALP activity (26,27), the influence of Ga ions on the akt signaling pathway in osteoblasts was investigated.…”

“…Based on the key roles of the Akt signaling pathway in regulating ALP activity ( 26 , 27 ), the influence of Ga ions on the Akt signaling pathway in osteoblasts was investigated. MC3T3-E1 osteoblasts were cultured in osteogenic induction medium with or without GaN (10 −4 M) for 0, 7 or 14 days.…”

Constructing a Sr2+-Substituted Surface Hydroxyapatite Hexagon-Like Microarray on 3D-Plotted Hydroxyapatite Scaffold to Regulate Osteogenic Differentiation

“…These results demonstrated that the Sr 2+ -substituted HA hexagon-like microarray obviously promoted the expression of BMP2. Furthermore, the expression level of BMP2 is closely related to cell osteogenic ability and BMP2 can activate the transcription of RUNX2 and Osterix [ 39 , 40 ].…”

“…As a significant transcription factor in the early stage of osteoblast differentiation and bone formation, Osterix can regulate the expression of bone-specific matrix protein- associated genes, such as ALP and OCN, and ultimately promote matrix mineralization [ 40 , 46 ]. When cells were cultured on the scaffold surface for 4 days, the expression level of Osterix was significantly higher in the 4Sr-HA group and the 8Sr-HA group than in other groups ( Figure 9 E); At 7 days, the expression level of Osterix was still significantly increased in the 8Sr-HA group, which may be related to the higher release rate of Sr 2+ in the 4Sr-HA group and the 8Sr-HA group.…”

Synonymous Mutations of Porcine Igf1r Extracellular Domain Affect Differentiation and Mineralization in MC3T3-E1 Cells

“…An intragenic IGF-1R deletion that was identified in a patient presented short stature ( Harmel et al, 2013 ). IGF-1R signaling, which is activated by IGF-1, plays an essential role in cell growth and development, as well as in bone formation via osteoblast-mediated bone mineralization ( Fang et al, 2019 ). IGF-1R is also involved in bone matrix mineralization.…”