Gene expression profiles and bioinformatics analysis of insulin‐like growth factor‐1 promotion of osteogenic differentiation

Abstract

Background Insulin‐like growth factor‐1 (IGF‐1) promotes osteoblast differentiation and mineralization. The objective of this study was to investigate the effects of IGF‐1 on proliferation, mineralization, alkaline phosphatase (ALP) synthesis, and gene expression of osteoblast differentiation in MC3T3‐E1 osteoblasts cells, and to explore gene expression profiling differential genes. Methods MC3T3‐E1 osteoblasts cells were cultured in medium with or without IGF‐1. The ALP assay was employed to determine the osteoblast mineralization, and Alizarin red S to stain for calcium deposits, which were the indicators of mature osteocytes. The living cell number was assessed by the Cell Counting Kit‐8 method. RNA‐seq analysis was applied to identify genes that were differentially expressed in with or without IGF‐1 as well as genes that varied between these two groups. The expression of osteogenic marker genes was determined by quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blot analysis. Result The cell number of osteoblasts exposed to IGF‐1 at 200 μg/L significantly increased compared with the control group. The ALP activity in IGF‐1‐treated cells was higher than that in the control group. IGF‐1 can increase ALP synthesis in osteoblasts in vitro. RNA‐seq analysis showed that 677 triggered differentially expressed genes by IGF, of which 383 genes were downregulated and 294 genes were upregulated. Gene ontology (GO) analysis showed that IGF‐1 caused a significant change in gene expression patterns. Conclusions This result suggested that IGF‐1 could probably promote the synthesis of organic matrix and mineralize action of bone. Osteogenic‐related genes (DMP1, PHEX, SOST, BMP2, RUNX2, OPN, and OCN) were significantly upregulated both in GO analysis and in pathway analysis to perform qRT‐PCR. Western blot analysis demonstrated that the Notch pathway was highly upregulated in MC3T3‐E1 cells.

Bone remodeling: an operational process ensuring survival and bone mechanical competence

“…IGF-1 recruits progenitor cells of the osteoblastic lineage 215 and promotes osteoblast differentiation and matrix mineralization by upregulating the osteogenesis‐related genes DMP1, PHEX, SOST, BMP2, RUNX2, OPN, and OCN. 216 Moreover, IGF-1 released from the bone matrix during bone resorption establishes an osteogenic microenvironment by activating mechanistic target of rapamycin (mTOR) signaling, 217 which is critical for cellular energy metabolism and cell migration. 218 Recent studies have confirmed that IGF-1-dependent activation of mTOR induces human dental pulp stem cell (DPSC) differentiation toward an osteoblastic phenotype.…”

Preparation, characterization, and osteogenic activity mechanism of casein phosphopeptide-calcium chelate

“…IGF1 is a key protein in bone formation and plays an important role in the regulation of bone conversion and osteogenic growth ( 68 – 70 ). Yuan et al found that IGF1 promoted the differentiation of osteoblasts ( 71 ). Furthermore, Xue et al found that IGF1 promoted osteogenic differentiation of rat bone marrow mesenchymal stem cells by increasing TAZ expression ( 72 ).…”

Transcriptome Analysis of Egg Yolk Sialoglycoprotein on Osteogenic Activity in MC3T3-E1 Cells

“…Recently, several studies used transcriptional profiling to address osteoblast differentiation. Some focus on gene expression profile of osteoporotic phenotype mice [41], and others used transcriptional analysis to investigate gene expression differences in osteoblast differentiation of MC3T3-E1 cells [42,43]. In this study, after we identified several common pathways and connected DEGs with potential biological pathways by transcriptome analysis, we found that EYG had an effect on several bone formation related pathways, such as TNF signaling pathway, complement and coagulation cascades, protein digestion and absorption, ECM-receptor interaction and focal adhesion.…”