Dataset Information

BM-MSC-derived exosomes alleviate radiation-induced bone loss by restoring the function of recipient BM-MSCs and activating Wnt/?-catenin signaling.

ABSTRACT: BACKGROUND:Radiotherapy to cancer patients is inevitably accompanied by normal tissue injury, and the bone is one of the most commonly damaged tissues. Damage to bone marrow mesenchymal stem cells (BM-MSCs) induced by radiation is thought to be a major cause of radiation-induced bone loss. Exosomes exhibit great therapeutic potential in the treatment of osteoporosis, but whether exosomes are involved in radiation-induced bone loss has not been thoroughly elucidated to date. The main purpose of this study is to investigate the role of exosomes derived from BM-MSCs in restoring recipient BM-MSC function and alleviating radiation-induced bone loss. METHODS:BM-MSC-derived exosomes were intravenously injected to rats immediately after irradiation. After 28?days, the left tibiae were harvested for micro-CT and histomorphometric analysis. The effects of exosomes on antioxidant capacity, DNA damage repair, proliferation, and cell senescence of recipient BM-MSCs were determined. Osteogenic and adipogenic differentiation assays were used to detect the effects of exosomes on the differentiation potential of recipient BM-MSCs, and related genes were measured by qRT-PCR and Western blot analysis. ?-Catenin expression was detected at histological and cytological levels. RESULTS:BM-MSC-derived exosomes can attenuate radiation-induced bone loss in a rat model that is similar to mesenchymal stem cell transplantation. Exosome-treated BM-MSCs exhibit reduced oxidative stress, accelerated DNA damage repair, and reduced proliferation inhibition and cell senescence-associate protein expression compared with BM-MSCs that exclusively received irradiation. Following irradiation, exosomes promote ?-catenin expression in BM-MSCs and restore the balance between adipogenic and osteogenic differentiation. CONCLUSIONS:Our findings indicate that BM-MSC-derived exosomes take effects by restoring the function of recipient BM-MSCs. Therefore, exosomes may represent a promising cell-free therapeutic approach for the treatment of radiation-induced bone loss.

SUBMITTER: Zuo R

PROVIDER: S-EPMC6334443 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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BM-MSC-derived exosomes alleviate radiation-induced bone loss by restoring the function of recipient BM-MSCs and activating Wnt/β-catenin signaling.

Zuo Rui R Liu Minghan M Wang Yanqiu Y Li Jie J Wang Wenkai W Wu Junlong J Sun Chao C Li Bin B Wang Ziwen Z Lan Weiren W Zhang Chao C Shi Chunmeng C Zhou Yue Y

Stem cell research & therapy 20190115 1

<h4>Background</h4>Radiotherapy to cancer patients is inevitably accompanied by normal tissue injury, and the bone is one of the most commonly damaged tissues. Damage to bone marrow mesenchymal stem cells (BM-MSCs) induced by radiation is thought to be a major cause of radiation-induced bone loss. Exosomes exhibit great therapeutic potential in the treatment of osteoporosis, but whether exosomes are involved in radiation-induced bone loss has not been thoroughly elucidated to date. The main purp ...[more]

PMID: 30646958

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Dataset Information

BM-MSC-derived exosomes alleviate radiation-induced bone loss by restoring the function of recipient BM-MSCs and activating Wnt/?-catenin signaling.

Publications

BM-MSC-derived exosomes alleviate radiation-induced bone loss by restoring the function of recipient BM-MSCs and activating Wnt/β-catenin signaling.

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