Department of Ultrasound Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
Clinical Research Center for Medical Imaging in Hubei Province, Wuhan, 430022, China.
Cell Mol Biol Lett. 2023 Jan 30;28(1):9. doi: 10.1186/s11658-023-00422-3.
Bone marrow-derived mesenchymal stem cells (BMSCs)-derived extracellular vesicles (EVs) have shown potent anti-inflammatory function in various pathological conditions, such as osteoarthritis and neurodegenerative diseases. Since the number of EVs naturally secreted by cells is finite and they usually bear specific repertoires of bioactive molecules to perform manifold cell-cell communication, but not one particular therapeutic function as expected, their practical application is still limited. Strategies are needed to increase the production of EVs and enhance their therapeutic function. Recent studies have suggested that low-intensity pulsed ultrasound (LIPUS) is a promising non-invasive method to increase the secretion of EVs and promote their anti-inflammatory effects. However, the effect of LIPUS stimulation of BMSCs on EVs derived from the cells remains unclear. The objective of this study was to investigate whether LIPUS stimulation on BMSCs could increase the secretion of EVs and enhance their anti-inflammatory effects.
BMSCs were exposed to LIPUS (300 mW/cm) for 15 min and EVs were isolated by ultracentrifugation. Anti-inflammatory effects of EVs were investigated on RAW264.7 cells in vitro and in the allogeneic skin transplantation model. Small RNA-seq was utilized to identify components difference in EVs with/without LIPUS irradiation.
In this study, we found that LIPUS stimulation could lead to a 3.66-fold increase in the EVs release from BMSCs. Moreover, both in vitro and in vivo experimental results suggested that EVs secreted from LIPUS-treated BMSCs (LIPUS-EVs) possessed stronger anti-inflammatory function than EVs secreted from BMSCs without LIPUS stimulation (C-EVs). RNA-seq analysis revealed that miR-328-5p and miR-487b-3p were significantly up-regulated in LIPUS-EVs compare with C-EVs. The suppression of MAPK signaling pathway by these two up-regulated miRNAs could be the potential mechanism of strengthened anti-inflammatory effects of LIPUS-EVs.
LIPUS stimulation on BMSCs could significantly increase the secretion of EVs. Moreover, EVs generated from LIPUS-treated BMSCs possessed much stronger anti-inflammatory function than C-EVs. Therefore, LIPUS could be a promising non-invasive strategy to promote the production of EVs from BMSCs and augment their anti-inflammatory effects.
骨髓间充质干细胞（BMSCs）衍生的细胞外囊泡（EVs）在多种病理条件下具有强大的抗炎功能，如骨关节炎和神经退行性疾病。由于细胞自然分泌的 EVs 数量有限，并且它们通常携带特定的生物活性分子谱来执行多种细胞间通讯，而不是预期的特定治疗功能，因此它们的实际应用仍然有限。需要采取策略来增加 EVs 的产量并增强其治疗功能。最近的研究表明，低强度脉冲超声（LIPUS）是一种有前途的非侵入性方法，可以增加 EVs 的分泌并促进其抗炎作用。然而，LIPUS 刺激 BMSCs 对细胞衍生的 EVs 的影响尚不清楚。本研究旨在探讨 LIPUS 刺激 BMSCs 是否可以增加 EVs 的分泌并增强其抗炎作用。
将 BMSCs 暴露于 LIPUS（300 mW/cm）15 分钟，通过超速离心分离 EVs。在体外和同种异体皮肤移植模型中研究 EVs 的抗炎作用。利用小 RNA-seq 鉴定有无 LIPUS 照射的 EVs 成分差异。
在这项研究中，我们发现 LIPUS 刺激可使 BMSCs 释放的 EVs 增加 3.66 倍。此外，体内外实验结果均表明，与未经 LIPUS 刺激的 BMSCs 分泌的 EVs（C-EVs）相比，LIPUS 处理的 BMSCs 分泌的 EVs（LIPUS-EVs）具有更强的抗炎功能。RNA-seq 分析显示，与 C-EVs 相比，LIPUS-EVs 中 miR-328-5p 和 miR-487b-3p 显著上调。这两种上调的 miRNA 对 MAPK 信号通路的抑制可能是 LIPUS-EVs 抗炎作用增强的潜在机制。
LIPUS 刺激 BMSCs 可显著增加 EVs 的分泌。此外，来自 LIPUS 处理的 BMSCs 的 EVs 比 C-EVs 具有更强的抗炎功能。因此，LIPUS 可能是一种有前途的非侵入性策略，可以促进 BMSCs 产生 EVs 并增强其抗炎作用。
