Extracellular vesicles containing miR-146a-5p secreted by bone marrow mesenchymal cells activate hepatocytic progenitors in regenerating rat livers

Abstract

Background Small hepatocyte-like progenitor cells (SHPCs) appear to form transient clusters in rat livers treated with retrorsine (Ret) and 70% partial hepatectomy (PH). We previously reported that the expansion of SHPCs was amplified in Ret/PH-treated rat livers transplanted with Thy1+ cells derived from d-galactosamine-treated injured livers. Extracellular vesicles (EVs) produced by hepatic Thy1+ donor cells activated SHPCs via interleukin (IL)-17 receptor B signaling. As bone marrow-derived mesenchymal cells (BM-MCs) also express Thy1, we aimed to determine whether BM-MCs could also promote the growth of SHPCs. Methods BM-MCs were isolated from dipeptidyl-peptidase IV (DPPIV)-positive rats. BM-MCs or BM-MC-derived EVs were administered to DPPIV-negative Ret/PH rat livers, and the growth and the characteristics of SHPC clusters were evaluated 14 days post-treatment. miRNA microarrays and cytokine arrays examined soluble factors within EVs. Small hepatocytes (SHs) isolated from an adult rat liver were used to identify factors enhancing hepatocytic progenitor cells growth. Results The recipient’s livers were enlarged at 2 weeks post-BM-MC transplantation. The number and the size of SHPCs increased remarkably in livers transplanted with BM-MCs. BM-MC-derived EVs also stimulated SHPC growth. Comprehensive analyses revealed that BM-MC-derived EVs contained miR-146a-5p, interleukin-6, and stem cell factor, which could enhance SHs’ proliferation. Administration of EVs derived from the miR-146a-5p-transfected BM-MCs to Ret/PH rat livers remarkably enhanced the expansion of SHPCs. Conclusions miR-146a-5p involved in EVs produced by BM-MCs may play a major role in accelerating liver regeneration by activating the intrinsic hepatocytic progenitor cells.

A new cell-free therapeutic strategy for liver regeneration: Human placental mesenchymal stem cell-derived extracellular vesicles

“…Previous research indicated that EVs cargos can play important role in modulating the recipient cell behavior in liver disease. Ichinohe et al 35 indicated that miR-146a-5p is involved in the production of EVs by BM-MCs, may play a major role in accelerating liver regeneration. Similarly, our results showed that the downregulated hPMSCs-EVs circ-RBM23 suppresses hepatocyte proliferation.…”

CINC-2 and miR-199a-5p in exosomes secreted by transplanted Thy1+ cells activate hepatocytic progenitor cell growth in rat liver regeneration

“…Clusters of SHPCs in recipient livers were collected by using laser microdissection, following the manufacturer's protocol [22,30]. Total RNA was isolated from the captured cells using the RNeasy Mini Kit (Qiagen, Hilden, Germany).…”

“…For miRNA expression analysis, miRNAs were transcribed into cDNA using the TaqMan MicroRNA Reverse Transcription kit (Applied Biosystems, Foster City, USA) and RT primers provided with the TaqMan miRNA assay (Applied Biosystems). The cDNA products were analyzed using TaqMan miRNA sequence-speci c probes for U6 small nuclear 2 (U6), miR-125b-5p, miR-145-5p, miR-199a-5p, miR-451-5p, miR-3473-5p, and let-7f, Premix Ex Taq (Takara), and the ABI Prism 7500 sequence detection system (Applied Biosystems) [30,31]. The primers used are listed in Supplemental Table 2.…”

“…EVs were separated from CM as reported [30]. Thy1 + cells were cultured for 5 d and washed with PBS and the medium was replaced with serum-free DMEM (Sigma-Aldrich Co.).…”

Extracellular Vehicles of Oxygen-Depleted Mesenchymal Stromal Cells: Route to Off-Shelf Cellular Therapeutics?

“…These include the miRNA-183-5p and microRNA-221-3p that both have been assigned to the neuroprotective effects of BMSC EVs [ 111 , 112 ]. Their protective effects in ischemia/reperfusion injury are also not restricted to neuronal tissues as has been reported in the hepatocellular context but, apparently, are mediated by another non-coding RNA cargo, the miRNA-146a-5p [ 113 , 114 ]. Moreover, in mouse models, BMSC EVs induce VEGFR1 and -2 expression of endothelial cells and promote endothelial tube formation in vitro [ 115 ].…”