Eirin Alfonso, Ferguson Christopher M, Zhu Xiang-Yang, Saadiq Ishran M, Tang Hui, Lerman Amir, Lerman Lilach O
Divisions of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States.
Cardiovascular Diseases, Mayo Clinic, Rochester, MN, United States.
Stem Cell Res. 2020 Jun 20;47:101877. doi: 10.1016/j.scr.2020.101877.
Mesenchymal stromal/stem cell (MSC)-derived extracellular vesicles (EVs) shuttle select MSC contents and are endowed with an ability to repair ischemic tissues. We hypothesized that exposure to cardiovascular risk factors may alter the microRNA cargo of MSC-derived EVs, blunting their capacity to repair the post-stenotic kidney in pigs with metabolic syndrome (MetS) and renal artery stenosis (RAS).
Porcine MSCs were harvested from abdominal fat after 16wks of Lean- or MetS-diet, and their EVs isolated and characterized using microRNA-sequencing. Lean- and MetS-EV protective effects were assessed in-vitro in human umbilical endothelial cells (HUVECs). To compare their in-vivo efficacy to repair ischemic tissues, allogeneic-EVs were intrarenally delivered in pigs after 6wks of MetS + RAS, and 4wks later, single-kidney renal blood flow (RBF) and glomerular filtration rate (GFR) were studied in-vivo, and microvascular architecture and injury ex-vivo. Lean-, MetS-, and MetS + RAS-sham served as controls (n = 6 each).
Ten microRNAs, capable of targeting several pro-angiogenic genes, were upregulated in MetS-EVs versus Lean-EVs. In vitro, MetS-EVs failed to increase tube number and length, and to boost HUVEC migration compared to Lean-EVs. Lean- and MetS-EVs were detected in the stenotic-kidney 4wks after injection in the vicinity of small vessels. RBF and GFR were lower in MetS + RAS versus MetS, and restored in MetS + RAS + Lean-EVs, but not in MetS + RAS + MetS-EVs. Furthermore, MetS-EVs failed to restore renal expression of angiogenic factors, improve microvascular density, or attenuate fibrosis.
MetS alters the microRNA cargo of MSC-derived EVs and impairs their functional potency, limiting the therapeutic efficacy of this endogenous cellular repair system.
间充质基质/干细胞（MSC）衍生的细胞外囊泡（EVs）可转运特定的MSC内容物，并具有修复缺血组织的能力。我们推测，暴露于心血管危险因素可能会改变MSC衍生的EVs中的微小RNA含量，削弱其修复患有代谢综合征（MetS）和肾动脉狭窄（RAS）的猪的狭窄后肾脏的能力。
在给予瘦肉型或MetS饮食16周后，从腹部脂肪中采集猪MSC，并使用微小RNA测序对其EVs进行分离和表征。在体外对人脐静脉内皮细胞（HUVECs）评估瘦肉型和MetS-EV的保护作用。为了比较它们修复缺血组织的体内疗效，在给予MetS + RAS 6周后，将同种异体EVs经肾内注射到猪体内，4周后，在体内研究单肾肾血流量（RBF）和肾小球滤过率（GFR），并在体外研究微血管结构和损伤情况。瘦肉型、MetS型和MetS + RAS假手术组作为对照（每组n = 6）。
与瘦肉型-EV相比，MetS-EV中有10种能够靶向多个促血管生成基因的微小RNA上调。在体外，与瘦肉型-EV相比，MetS-EV未能增加管腔数量和长度，也未能促进HUVEC迁移。注射后4周，在狭窄肾脏的小血管附近检测到瘦肉型和MetS-EV。与MetS组相比，MetS + RAS组的RBF和GFR较低，在MetS + RAS + 瘦肉型-EV组中恢复，但在MetS + RAS + MetS-EV组中未恢复。此外，MetS-EV未能恢复促血管生成因子的肾脏表达，改善微血管密度或减轻纤维化。
MetS改变了MSC衍生的EVs中的微小RNA含量，并损害了其功能效力，限制了这种内源性细胞修复系统的治疗效果。
