Irradiation alters the differentiation potential of bone marrow mesenchymal stem cells

Abstract

Bone injury following radiotherapy has been confirmed by epidemiological and animal studies. However, the underlying mechanism remains to be elucidated and no preventive or curative solution has been identified for this bone loss. The present study aimed to investigate the irradiation-altered osteogenesis and adipogenesis of bone marrow mesenchymal stem cells (BMSCs). BMSCs were derived and exposed to γ-irradiation at doses of 0, 0.25, 0.5, 1, 2, 5 and 10 Gy. Cell viability was assessed using a 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide assay, and clonal expansion in vitro was detected by colony forming unit assessment. The osteogenic differentiation ability was demonstrated by alkaline phosphatase (ALP) activity, ALP staining and mineralization alizarin red staining, and the adipogenic differentiation ability was determined using Oil O red staining. The osteogenesis-associated genes, RUNX2, ALP, osteocalcin (OCN) and adipogenesis-associated genes, PPAR-γ and C/EBPα, were detected using reverse transcription-quantitative polymerase chain reaction analyses. The protein expression levels of RUNX2, ALP and PPAR-γ were detected using western blotting. Compared with the control, significant decreases in the proliferation, ALP activity and mineralization ability of the BMSCs were observed in the γ-irradiation group, with a high level of correlation with the exposure dose. However, no significant changes were observed in the area of Oil red O positive staining. The mRNA levels of RUNX2, ALP and OCN were decreased (P<0.05), however, no significant changes were observed in the levels of C/EBPα and PPAR-γ. The protein expression levels of RUNX2 and ALP were decreased in the irradiated BMSCs, however, no significant difference was observed in the protein expression of PPAR-γ. Irradiation inhibited the osteogenic and adipogenic ability of the BMSCs, and the osteogenic differentiation was decreased. The results of the present study provided evidence to assist in further elucidating radiotherapy-associated side effects on the skeleton.

Suppression of Sclerostin Alleviates Radiation-Induced Bone Loss by Protecting Bone-Forming Cells and Their Progenitors Through Distinct Mechanisms

“…Radiation preferentially induces adipogenesis in both MSCs and stromal cells, leading to shrinkage of the progenitor population. Interestingly, we (data not shown) and others have found that in vitro radiation does not directly accelerate the adipogenic differentiation of cultured MSCs, indicating that this is not a cell‐intrinsic mechanism. How radiation causes marrow adiposity in vivo is still largely unknown.…”

The Incorporation of Extracellular Vesicles from Mesenchymal Stromal Cells Into CD34+ Cells Increases Their Clonogenic Capacity and Bone Marrow Lodging Ability

“…It should be noted that bone marrow (BM) stroma remains of host origin after allo‐SCT and can be damaged because of a number of factors, including chemotherapy, infections or their treatments, graft‐versus‐host disease, or high‐dose radiotherapy .…”

Indirect effects of X-irradiation on proliferation and osteogenic potential of bone marrow mesenchymal stem cells in a local irradiated rat model

“…Specifically, the medium was prepared by supplementing DMEM with 15% FBS, 50 mg/l ascorbic acid and 10 −8 M dexamethasone (both from Sigma-Aldrich), 10 mM β-glycerol phosphate (China Pharmaceutical Shanghai Chemical Reagent Co., Ltd.) (17,23) and 100 U/ml penicillin and streptomycin (North China Pharmaceutical Co., Ltd.). The medium was changed every 3 days.…”