静脉注射骨髓间充质干细胞调节 tsRNA 表达并改善 COPD 小鼠的肺重构。

Intravenous injection of BMSCs modulate tsRNA expression and ameliorate lung remodeling in COPD mice.

机构信息

Department of Respiratory and Critical Care Medicine, The Third Xiangya Hospital of Central South University, Changsha, China.

出版信息

Stem Cell Res Ther. 2024 Nov 25;15(1):450. doi: 10.1186/s13287-024-04066-8.

DOI:10.1186/s13287-024-04066-8

PMID:39587604

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11590572/

Abstract

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by lung remodeling induced by chronic inflammation, presenting challenges for effective treatment. Mesenchymal stem cells (MSCs) and their extracellular vesicles (EVs) have shown promise in mitigating inflammation and tissue repairing in various diseases, including COPD. However, the optimal therapeutic pathways for different stages of COPD remain unclear. Transfer RNA-derived small RNAs (tsRNAs) are emerging as key regulators of cellular processes. However, their role in COPD and MSC therapy remains poorly understood.

METHODS

This study explored the optimal administration routes and efficacy of bone marrow mesenchymal stem cells (BMSCs) and their extracellular vesicles (BMSC-EVs) in treating inflammatory or emphysematous COPD stages in mouse models. Male C57BL/6 mice were exposed to cigarette smoke daily for 6 or 16 weeks, with intraperitoneal CSE injections every 10 days, to model different stages of COPD. Mice were then treated with tracheal or intravenous injections of BMSCs or BMSC-EVs. PKH26 fluorescent dye labeled BMSCs and BMSC-EVs for pulmonary distribution observation. Lung tissue inflammation, apoptosis, EMT, and collagen deposition were assessed using HE staining, TUNEL assay, immunohistochemistry, and Sirius Red staining. Gene and tsRNA expression in lung tissues were analyzed by high-throughput sequencing. Differentially expressed tsRNAs (DE-tsRNAs) were validated by RT-qPCR. Statistical analysis was performed using GraphPad Prism 9.0. Data are presented as mean ± standard deviation (SD).

RESULTS

In 16-week COPD mice characterized by emphysema, tracheal administration of BMSC-EVs showed more significant lung distribution and inhibition of emphysematous pathology. In 6-week COPD mice characterized by inflammation, intravenous injection of BMSCs led to significant pulmonary homing, significantly reduced lung inflammation, apoptosis, EMT, and collagen deposition (P < 0.05). High-throughput sequencing indicated BMSC treatment downregulated genes related to these processes while upregulating mitochondrial function genes. Co-expression networks of DE-tsRNAs and target genes suggested potential roles in COPD. RT-qPCR confirmed significant differential expression of two DE-tsRNAs during COPD progression and BMSC treatment (P < 0.05).

CONCLUSIONS

Our study provides insights into selecting MSC and MSC-EV administration routes for different COPD stages. High-throughput sequencing supports BMSCs' inhibitory effects on lung remodeling and identifies the first tsRNA expression profile in a COPD model, warranting further investigation.

摘要

背景

慢性阻塞性肺疾病（COPD）的特征是慢性炎症引起的肺重塑，这给有效治疗带来了挑战。间充质干细胞（MSCs）及其细胞外囊泡（EVs）在减轻各种疾病（包括 COPD）的炎症和组织修复方面显示出了潜力。然而，不同阶段 COPD 的最佳治疗途径仍不清楚。转移 RNA 衍生的小 RNA（tsRNAs）作为细胞过程的关键调节剂而出现。然而，它们在 COPD 和 MSC 治疗中的作用仍知之甚少。

方法

本研究探讨了骨髓间充质干细胞（BMSCs）及其细胞外囊泡（BMSC-EVs）在治疗小鼠模型中炎症或肺气肿 COPD 阶段的最佳给药途径和疗效。雄性 C57BL/6 小鼠每天接受香烟烟雾暴露，每 10 天接受腹腔内 CSE 注射，以模拟不同阶段的 COPD。然后，通过气管内或静脉内注射 BMSCs 或 BMSC-EVs 进行治疗。PKH26 荧光染料标记 BMSCs 和 BMSC-EVs 以观察肺内分布。通过 HE 染色、TUNEL 检测、免疫组织化学和天狼星红染色评估肺组织炎症、细胞凋亡、EMT 和胶原沉积。通过高通量测序分析肺组织中的基因和 tsRNA 表达。通过 RT-qPCR 验证差异表达的 tsRNAs（DE-tsRNAs）。使用 GraphPad Prism 9.0 进行统计分析。数据表示为均值±标准差（SD）。

结果

在以肺气肿为特征的 16 周 COPD 小鼠中，气管内给予 BMSC-EVs 显示出更显著的肺分布和对肺气肿病理的抑制作用。在以炎症为特征的 6 周 COPD 小鼠中，静脉内注射 BMSCs 导致显著的肺归巢，显著减少肺炎症、细胞凋亡、EMT 和胶原沉积（P<0.05）。高通量测序表明 BMSC 治疗下调了与这些过程相关的基因，同时上调了与线粒体功能相关的基因。DE-tsRNAs 和靶基因的共表达网络表明其在 COPD 中的潜在作用。RT-qPCR 证实了两种 DE-tsRNAs 在 COPD 进展和 BMSC 治疗过程中的差异表达（P<0.05）。