Exosome lncRNA IFNG-AS1 derived from mesenchymal stem cells of human adipose ameliorates neurogenesis and ASD-like behavior in BTBR mice.

BACKGROUND: The transplantation of exosomes derived from human adipose-derived mesenchymal stem cells (hADSCs) has emerged as a prospective cellular-free therapeutic intervention for the treatment of neurodevelopmental disorders (NDDs), as well as autism spectrum disorder (ASD). Nevertheless, the efficacy of hADSC exosome transplantation for ASD treatment remains to be verified, and the underlying mechanism of action remains unclear. RESULTS: The exosomal long non-coding RNAs (lncRNAs) from hADSC and human umbilical cord mesenchymal stem cells (hUCMSC) were sequenced and 13,915 and 729 lncRNAs were obtained, respectively. The lncRNAs present in hADSC-Exos encompass those found in hUCMSC-Exos and are associated with neurogenesis. The biodistribution of hADSC-Exos in mouse brain ventricles and organoids was tracked, and the cellular uptake of hADSC-Exos was evaluated both in vivo and in vitro. hADSC-Exos promote neurogenesis in brain organoid and ameliorate social deficits in ASD mouse model BTBR T + tf/J (BTBR). Fluorescence in situ hybridization (FISH) confirmed lncRNA Ifngas1 significantly increased in the prefrontal cortex (PFC) of adult mice after hADSC-Exos intraventricular injection. The lncRNA Ifngas1 can act as a molecular sponge for miR-21a-3p to play a regulatory role and promote neurogenesis through the miR-21a-3p/PI3K/AKT axis. CONCLUSION: We demonstrated hADSC-Exos have the ability to confer neuroprotection through functional restoration, attenuation of neuroinflammation, inhibition of neuronal apoptosis, and promotion of neurogenesis both in vitro and in vivo. The hADSC-Exos-derived lncRNA IFNG-AS1 acts as a molecular sponge and facilitates neurogenesis via the miR-21a-3p/PI3K/AKT signaling pathway, thereby exerting a regulatory effect. Our findings suggest a potential therapeutic avenue for individuals with ASD.

Single-cell analysis of the miRNA activities in tuberculous meningitis (TBM) model mice injected with the BCG vaccine.

BACKGROUND: Our previous study revealed the transcriptome atlas of specific cell types in tuberculous meningitis (TBM) model mice injected with the BCG vaccine via scRNA sequencing. However, the activities of miRNAs in TBM at single-cell resolution remain to be explored. METHOD: Cell type-specific miRNA activities were investigated by using motif enrichment analyses (miReact) on the transcriptome data of 15 cell types. The target mRNAs of miRNAs were predicted and subjected to enrichment analysis. Furthermore, miRNAs and their target mRNAs with opposite expression trends were chosen to construct functional networks. Besides, qRT-PCR and RNA scope were performed to verify the expression level of representative miRNA. RESULTS: The tSNE dimensionality reduction presented 15 cell types in TBM model mice, in which microglia and endothelial cells accounted for the majority. Target mRNAs of each cell type were predicted for verification or network construction. The immune and inflammation-related miRNA-mRNA networks of macrophages and microglia, oxidative phosphorylation-related miRNA-mRNA networks of neurons, ion and protein transport-related networks of epididymal cells, and angiogenesis-related miRNA-mRNA networks of VSMCs were constructed. The miRNA activity analysis revealed that miR-21a-3p activity was increased in microglia, macrophages, neurons and epididymal cells. The result of qRT-PCR and RNA scope indicate that miR-21a-3p was significantly higher-expressed in TBM brain tissue compared with normal brain tissue. CONCLUSION: In our study, an in-depth exploration of the mRNA expression and miRNA activity of macrophages, microglia, epididymal cells, neurons and vascular smooth muscle cells during TBM progression was conducted using scRNA-Seq, which provided novel insights into the immune cell engagement in TBM patients.

MicroRNA-21-3p Engineered Umbilical Cord Stem Cell-Derived Exosomes Inhibit Tendon Adhesion.

PURPOSE: As a common complication of tendon injury, tendon adhesion is an unresolved problem in clinical work. The aim of this study was to investigate whether human umbilical cord mesenchymal stem cell-derived exosomes (HUMSC-Exos), one of the most promising new-generation cell-free therapeutic agents, can improve tendon adhesion and explore potential-related mechanisms. METHODS: The rat Achilles tendon injury adhesion model was constructed in vivo, and the localization of HUMSC-Exos was used to evaluate the tendon adhesion. Rat fibroblast cell lines were treated with transforming growth factor ß1 (TGF-ß1) and/or HUMSC-Exos in vitro, and cell proliferation, apoptosis and gene expression were measured. MicroRNA (miRNA) sequencing and quantitative PCR (qPCR) analysis confirmed differential miRNAs. A specific miRNA antagonist (antagomir-21a-5p) was used to transform HUMSC-Exos and obtain modified exosomes to verify its efficacy and related mechanism of action. RESULTS: In this study, we found HUMSC-Exos reduced rat fibroblast proliferation and inhibited the expression of fibrosis genes: collagen III (COL III) and α-smooth muscle actin (α-SMA) in vitro. In the rat tendon adhesion model, topical application of HUMSC-Exos contributed to relief of tendon adhesion. Specifically, the fibrosis and inflammation-related genes were simultaneously inhibited by HUMSC-Exos. Further, miRNA sequencing of HUMSCs and HUMSC-Exos showed that miR-21a-3p was expressed at low abundance in HUMSC-Exos. The antagonist targeting miR-21a-3p was recruited for treatment of HUMSCs, and harvested HUMSC-Exos, which expressed low levels of miR-21a-3p, and expanded the inhibition of tendon adhesion in subsequent in vitro experiments. CONCLUSION: Our results indicate that HUMSC-Exos may manipulate p65 activity by delivering low-abundance miR-21a-3p, ultimately inhibiting tendon adhesion. The findings may be promising for dealing with tendon adhesion.

Dicer knockdown inhibits endothelial cell tumor growth via microRNA 21a-3p targeting of Nox-4.

MicroRNAs (miR) are emerging as biomarkers and potential therapeutic targets in tumor management. Endothelial cell tumors are the most common soft tissue tumors in infants, yet little is known about the significance of miR in regulating their growth. A validated mouse endothelial cell (EOMA) tumor model was used to demonstrate that post-transcriptional gene silencing of dicer, the enzyme that converts pre-miR to mature miR, can prevent tumor formation in vivo. Tumors were formed in eight of eight mice injected with EOMA cells transfected with control shRNA but formed in only four of ten mice injected with EOMA cells transfected with dicer shRNA. Tumors that formed in the dicer shRNA group were significantly smaller than tumors in the control group. This response to dicer knockdown was mediated by up-regulated miR 21a-3p activity targeting the nox-4 3'-UTR. EOMA cells were transfected with miR 21a-3p mimic and luciferase reporter plasmids containing either intact nox-4 3'-UTR or with mutation of the proposed 3'-UTR miR21a-3p binding sites. Mean luciferase activity was decreased by 85% in the intact compared with the site mutated vectors (p < 0.01). Attenuated Nox-4 activity resulted in decreased cellular hydrogen peroxide production and decreased production of oxidant-inducible monocyte chemoattractant protein-1, which we have previously shown to be critically required for endothelial cell tumor formation. These findings provide the first evidence establishing the significance of dicer and microRNA in promoting endothelial cell tumor growth in vivo.