Transglutaminase 2 Prevents Premature Senescence and Promotes Osteoblastic Differentiation of Mesenchymal Stem Cells through NRF2 Activation

Figure 4

TG2 is required for osteoblastic but not adipocytic differentiation of MSC. (a) The mRNA level of TG2 after induction of osteoblast differentiation was assessed using RNA sequencing data from the Gene Expression Omnibus (GEO) database (GSE159138). (b) The mRNA levels of osteoblast markers (SPP1, SPARC, ALPL, and RUNX2) in wild-type and TG2-knockdowned MSCs. The mRNA levels were measured by real-time PCR after 2-week culture in differentiation-inducing media. (c) Staining for osteogenic differentiation. After a 3-week culture in differentiation-inducing media, Alizarin red staining was used to characterize osteoblasts that were differentiated from control or TG2-knockdowned MSCs. (d) The mRNA levels of adipocyte markers (PPARG, CEBPA, FABP4, and CFD) in wild-type and TG2-knockdowned MSCs. The mRNA levels were measured by real-time PCR after 2-week culture in differentiation-inducing media. (e) Staining for adipogenic differentiation. After a 3-week culture in differentiation-inducing media, oil red O staining was used to characterize adipocytes that were differentiated from control or TG2-knockdowned MSCs. The real-time PCR assay was repeated in three independent experiments, and representative results were presented. The information is presented as the mean values and their corresponding SEM. These values were derived from three technical replicates performed within a single experiment. Statistical significance was tested by Student’s t-test (n = 3; ; ).

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