title: Mesenchymal stem cells deliver exogenous miRNAs to neural cells and induce their differentiation and glutamate transporter expression.
abstract: MicroRNAs (miRNAs) are potential therapeutic targets in a variety of pathological conditions in the brain; however, their clinical application is hampered by lack of efficient delivery modes. Mesenchymal stromal stem cells (MSCs) migrate to sites of injury and inflammation and exert therapeutic effects in various neurological disorders. Here, we examined the ability of MSCs to deliver exogenous miRNA mimics and pre-miRNAs to human neural progenitor cells (NPCs) and astrocytes and characterized the functional impact of this delivery. We found that MSCs efficiently delivered fluorescent-labeled miR-124 and miR-145 mimics to cocultured NPCs and astrocytes. We further demonstrated the delivery of the miRNAs using novel reporter plasmids that contain a sequence complementary to miR-124 or miR-145 downstream of luciferase or mCherry. Binding of the specific miRNAs to these sequences results in decreased luciferase activity or mCherry fluorescence and therefore enable analysis of miRNA delivery in living cells. The delivered exogenous miR-124 significantly decreased the expression of the target gene Sox9 by targeting its 3'-UTR, and increased the neuronal differentiation of the NPCs. In addition, the delivered miR-124 increased the expression of the glutamate transporters, EAAT1 in NPCs and EAAT2 in both NPCs and astrocytes. Similar results were obtained with MSCs transfected with pre-miR-124. The miRNA delivery was mediated by MSC-derived exosomes and was cell contact independent. These results suggest that MSCs can functionally deliver exogenous miRNAs to neural cells and provide an efficient route of therapeutic miRNA delivery to the brain in pathological conditions with clinical implications for regenerative medicine.
authors.affiliation: 1 Davidson Laboratory of Cell Signaling and Tumorigenesis, Department of Neurosurgery, Hermelin Brain Tumor Center , Henry Ford Hospital, Detroit, Michigan.
authors.forename: Hae Kyung
authors.initials: HK
authors.lastname: Lee
authors.forename: Susan
authors.initials: S
authors.lastname: Finniss
authors.forename: Simona
authors.initials: S
authors.lastname: Cazacu
authors.forename: Cunli
authors.initials: C
authors.lastname: Xiang
authors.forename: Chaya
authors.initials: C
authors.lastname: Brodie
mesh_terms: D020413:3' Untranslated Regions; D002454:Cell Differentiation; D027341:Excitatory Amino Acid Transporter 1 / Q000096:biosynthesis* / Q000235:genetics; D027342:Excitatory Amino Acid Transporter 2; D005786:Gene Expression Regulation / Q000235:genetics; D050491:Glutamate Plasma Membrane Transport Proteins / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism; D058953:Neural Stem Cells / Q000166:cytology / Q000378:metabolism*; D055758:SOX9 Transcription Factor / Q000096:biosynthesis
chemical_list: D020413:3' Untranslated Regions; D027341:Excitatory Amino Acid Transporter 1; D027342:Excitatory Amino Acid Transporter 2; D050491:Glutamate Plasma Membrane Transport Proteins; C509207:MIRN124 microRNA, human; C541010:MIRN145 microRNA, human; D035683:MicroRNAs; C493397:SLC1A2 protein, human; C493394:SLC1A3 protein, human; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human