Yin Hu1, Ran Xu2, Chun-Yuan Chen1, Shan-Shan Rao3, Kun Xia1, Jie Huang1, Hao Yin1, Zhen-Xing Wang4, Jia Cao4, Zheng-Zhao Liu4, Yi-Juan Tan4, Juan Luo4, Hui Xie5. 1. Movement System Injury and Repair Research Center, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China. 2. Department of Urology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China. 3. Movement System Injury and Repair Research Center, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Xiangya Nursing School, Central South University, Changsha, Hunan 410013, China. 4. Movement System Injury and Repair Research Center, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China. 5. Movement System Injury and Repair Research Center, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Hunan Key Laboratory of Organ Injury, Aging and Regenerative Medicine, Changsha, Hunan 410008, China; Hunan Key Laboratory of Bone Joint Degeneration and Injury, Changsha, Hunan 410008, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China. Electronic address: huixie@csu.edu.cn.
Abstract
OBJECTIVE: Senile osteoporosis is one of the most common age-related diseases worldwide. Accumulating evidences have indicated that young blood can reverse age-related impairments. Extracellular vesicles (EVs) exert therapeutic effects in a variety of diseases by delivering bioactive molecules such as microRNAs (miRNAs). The aim of the study is to evaluate the therapeutic potential of EVs from human umbilical cord blood plasma (UCB-EVs) on senile osteoporosis and to preliminarily clarify the underlying mechanism. METHODS: UCB-EVs were injected into the tail vein of aged (16 months old) male C57BL/6 mice. Microcomputed tomography was performed to evaluate bone mass and microarchitecture of mice. The osteogenic and osteoclastic activities were determined by quantitative real-time PCR (qRT-PCR), histological examination and western blot analysis. In vitro, qRT-PCR assay was undertaken to explore the enrichment levels of a number of miRNAs that have positive effects in reducing bone loss. The efficacy of UCB-EVs on osteoblastic differentiation of bone marrow mesenchymal stromal cells (BMSCs) and osteoclastogenesis of RAW264.7 cells were assessed by cytochemical staining. Gene and protein expression changes were detected by qRT-PCR and western blotting respectively. Meanwhile, the roles of the selected miRNA in the regulatory effects of UCB-EVs on BMSCs and RAW264.7 cells were evaluated by using specific miRNA inhibitor. RESULTS: The intravenous injection of UCB-EVs for two months attenuated bone loss in old mice, as defined by increased trabecular and cortical bone mass, enhanced osteoblast formation and reduced osteoclast formation compared to the control mice. In vitro, UCB-EVs could promote the osteogenic differentiation of BMSCs and inhibit the osteoclastogenesis of RAW264.7 cells. Moreover, it was confirmed that miR-3960 was highly enriched in UCB-EVs and miR-3960 inhibitor reversed the stimulatory effect of UCB-EVs on osteoblastic differentiation of BMSCs. CONCLUSION: Our findings indicate that UCB-EVs ameliorate age-related bone loss by stimulating bone formation and inhibiting bone resorption, and miR-3960 mediated the osteogenic effect of UCB-EVs on BMSCs. Thus, UCB-EVs may represent a promising agent for prevention of senile osteoporosis.
OBJECTIVE:Senile osteoporosis is one of the most common age-related diseases worldwide. Accumulating evidences have indicated that young blood can reverse age-related impairments. Extracellular vesicles (EVs) exert therapeutic effects in a variety of diseases by delivering bioactive molecules such as microRNAs (miRNAs). The aim of the study is to evaluate the therapeutic potential of EVs from human umbilical cord blood plasma (UCB-EVs) on senile osteoporosis and to preliminarily clarify the underlying mechanism. METHODS:UCB-EVs were injected into the tail vein of aged (16 months old) male C57BL/6 mice. Microcomputed tomography was performed to evaluate bone mass and microarchitecture of mice. The osteogenic and osteoclastic activities were determined by quantitative real-time PCR (qRT-PCR), histological examination and western blot analysis. In vitro, qRT-PCR assay was undertaken to explore the enrichment levels of a number of miRNAs that have positive effects in reducing bone loss. The efficacy of UCB-EVs on osteoblastic differentiation of bone marrow mesenchymal stromal cells (BMSCs) and osteoclastogenesis of RAW264.7 cells were assessed by cytochemical staining. Gene and protein expression changes were detected by qRT-PCR and western blotting respectively. Meanwhile, the roles of the selected miRNA in the regulatory effects of UCB-EVs on BMSCs and RAW264.7 cells were evaluated by using specific miRNA inhibitor. RESULTS: The intravenous injection of UCB-EVs for two months attenuated bone loss in old mice, as defined by increased trabecular and cortical bone mass, enhanced osteoblast formation and reduced osteoclast formation compared to the control mice. In vitro, UCB-EVs could promote the osteogenic differentiation of BMSCs and inhibit the osteoclastogenesis of RAW264.7 cells. Moreover, it was confirmed that miR-3960 was highly enriched in UCB-EVs and miR-3960 inhibitor reversed the stimulatory effect of UCB-EVs on osteoblastic differentiation of BMSCs. CONCLUSION: Our findings indicate that UCB-EVs ameliorate age-related bone loss by stimulating bone formation and inhibiting bone resorption, and miR-3960 mediated the osteogenic effect of UCB-EVs on BMSCs. Thus, UCB-EVs may represent a promising agent for prevention of senile osteoporosis.