Mehanna Radwa A, Elkafrawy Hagar, Essawy Marwa M, Ibrahim Samar S, Awaad Ashraf K, Khalil Nehal A, Kholief Marwa A, Sallam Abeer, Hamed Heba A, Barkat Mona A, ElKady Mohamed F, Thabet Eman H
Medical Physiology Department, Faculty of Medicine, Alexandria University, Alexandria, 21500, Egypt.
Center of Excellence for Research in Regenerative Medicine and Applications (CERRMA), Faculty of Medicine, Alexandria University, Alexandria, 21500, Egypt.
Biol Res. 2025 Mar 5;58(1):12. doi: 10.1186/s40659-025-00593-7.
Ischemic reperfusion (IR) generates reactive oxygen species (ROS) that inevitably result in myocardial cell death and heart failure. The regenerative power of cardiac progenitor/stem pools (CSCs), especially the Sca1 population, in response to IR injury remains unclear.
Our work sought to investigate whether small extracellular vesicles (sEVs) isolated from bone marrow-mesenchymal stem cells (BMMSCs) could rescue CSCs, specifically Sca-1+/CSCs, from IR by increasing their proliferative capacity and limiting their apoptosis in vitro. The Sca-1+/CSCs-IR model was induced by the oxygen-glucose deprivation/reoxygenation method (OGD/R). The effects of treatment with BMMSCs-derived sEVs on oxidative stress, cell proliferation, apoptosis, and cell cycle were assessed. To further test the mechanistic action, we assessed the PTEN/pAkt/HIF-1α pathway.
Compared to hypoxic untreated CSCs, BMMSCs-derived sEVs-treated cells had shifted from their quiescent to proliferative phase (p > 0.05) and showed decreased apoptosis (p < 0.001). sEVs-treated CSCs were predominately in the S phase (11.8 ± 0.9%) (p < 0.01). We identified an abundance of miRNA-21-5P in BMMSCs. HIF-1α expression was highest in CSCs treated with sEVs (p < 0.05). Moreover, miRNA-21-5p-rich sEVs shifted the redox state, reducing oxidative stress and promoting balance (p > 0.05).
Conditioning Sca-1+/CSCs, an essential population in the postnatal heart, with sEVs rich in miRNA-21 robustly enhanced the proliferation, and synthesis phase of the cell cycle, and stabilized HIF-1α while alleviating oxidative stress and apoptosis. Such sEVs rich in miRNA-21-5p can be further used as a preconditioning tool to enhance endogenous Sca-1+/CSCs regeneration in response to IR injury.
缺血再灌注（IR）会产生活性氧（ROS），不可避免地导致心肌细胞死亡和心力衰竭。心脏祖细胞/干细胞池（CSCs），尤其是Sca1群体，对IR损伤的再生能力仍不清楚。
我们的研究旨在探讨从骨髓间充质干细胞（BMMSCs）中分离出的小细胞外囊泡（sEVs）是否能通过提高其增殖能力并在体外限制其凋亡来挽救CSCs，特别是Sca-1+/CSCs，使其免受IR损伤。Sca-1+/CSCs-IR模型通过氧糖剥夺/复氧法（OGD/R）诱导。评估了BMMSCs来源的sEVs处理对氧化应激、细胞增殖、凋亡和细胞周期的影响。为了进一步测试其作用机制，我们评估了PTEN/pAkt/HIF-1α通路。
与未处理的缺氧CSCs相比，BMMSCs来源的sEVs处理的细胞已从静止期转变为增殖期（p＞0.05），且凋亡减少（p＜0.001）。sEVs处理的CSCs主要处于S期（11.8±0.9%）（p＜0.01）。我们在BMMSCs中鉴定出大量的miRNA-21-5P。HIF-1α在sEVs处理的CSCs中表达最高（p＜0.05）。此外，富含miRNA-21-5p的sEVs改变了氧化还原状态，降低了氧化应激并促进了平衡（p＞0.05）。
用富含miRNA-21的sEVs处理出生后心脏中的重要群体Sca-1+/CSCs，可有力地增强细胞周期的增殖和合成期，并稳定HIF-1α，同时减轻氧化应激和凋亡。这种富含miRNA-21-5p的sEVs可进一步用作预处理工具，以增强内源性Sca-1+/CSCs对IR损伤的再生能力。
