Spinal Cord Injury Affects Gene Expression of Transmembrane Proteins in Tissue and Release of Extracellular Vesicle in Blood: In Silico and In Vivo Analysis.

OBJECTIVE: Spinal cord injury (SCI) can disrupt membrane transmission by affecting transmembrane channels or neurotransmitter release. This study aimed to explore gene expression changes of transmembrane proteins underlying SCI through bioinformatics approaches and confirming in SCI model in rats. MATERIALS AND METHODS: In this experimental study, the differentially expressed genes (DEGs) in acute and subacute SCI were obtained based on microarray data downloaded from the gene expression omnibus (GEO). Transmembrane proteins of DEGs were recognized by using the UniProt annotation and transmembrane helices prediction (TMHMM) methods. The model of SCI was established through a weight-dropping procedure in rats. To confirm the SCI model, hematoxylin and eosin (H and E) staining was performed. Total mRNA was extracted from spinal cord tissues, and the RNA expression profile of some of the significantly changed genes in the previous part that has been confirmed by real-time polymerase chain reaction (PCR). Blood was collected from rats before sacrificing. Extracellular vesicles (EVs) were isolated by high-speed centrifugation from plasma. For the assessment of protein expression, western blotting was used. RESULTS: Based on bioinformatics analysis, we candidated a set of membrane proteins in SCI's acute and sub-acute phases, and confirmed significant upregulation in Grm1, Nrg1, CD63, Enpp3,and Cxcr4 between the acute and control groups and downregulation in Enpp3 between acute and subacute groups at the RNA level. Considering CD63 as an EV marker, we examined the protein expression of CD9 and CD63 in the plasma-derived EVs, and CD9 has significant expression between acute and control groups. We also demonstrate no significant CD63 and Cxcr4 expressions between groups. CONCLUSION: Our results provide new insight into the relationship between candidate transmembrane protein expression and different stages of SCI using in-silico approaches. Also, results show the release of EVs in blood in each group after SCI helping enlarge strategies to enhance recovery following SCI.

Clonal mesenchymal stem cell-derived extracellular vesicles improve mouse model of weight drop-induced traumatic brain injury through reducing cistauosis and apoptosis.

OBJECTIVE: Traumatic brain injury (TBI) is a major risk factor for disabilities globally with no effective treatment thus far. Recently, homogenous population of clonal mesenchymal stem cells (cMSC) and their derived extracellular vesicles (cMSC-EVs) have been proposed as a promising TBI treatment strategy. We herein investigated possible therapeutic effect of cMSC-EVs in TBI treatment and the underlying mechanisms considering cis p-tau as an early hallmark of TBI. METHODS: We examined the EVs morphology, size distribution, marker expression, and uptake. Moreover, the EVs neuroprotective effects were studied in both in-vitro and in-vivo model. We also examined the anti-cis p-tau antibody-loading characteristics of the EVs. We treated TBI mouse model with EVs; prepared from cMSC-conditioned media. TBI mice were given cMSC-EVs intravenously and their cognitive functions were analyzed two months of the treatment. We employed immunoblot analysis to study the underlying molecular mechanisms. RESULTS: We observed a profound cMSC-EVs uptake by primary cultured neurons. We found a remarkable neuroprotective effect of cMSC-EVs upon nutritional deprivation stress. Furthermore, cMSC-EVs were effectively loaded with an anti-cis p-tau antibody. There was a significant improvement in cognitive function in TBI animal models treated with cMSC-EVs compared to the saline-treated group. There was a decreased cis p-tau and cleaved caspase3 as well as increased p-PI3K in all treated animals. CONCLUSIONS: The results revealed that cMSC-EVs efficiently improved animal behaviors after TBI by reducing cistauosis and apoptosis. Moreover, the EVs can be employed as an effective strategy for antibody delivery during passive immunotherapy.

Regenerative potential of different extracellular vesicle subpopulations derived from clonal mesenchymal stem cells in a mouse model of chemotherapy-induced premature ovarian failure.

AIMS: Some studies have shown that mesenchymal stem cells (MSCs) and their derived extracellular vesicles (MSC-EVs) can restore ovarian function in premature ovarian failure (POF), however, concerns about their efficacy are attributed to the heterogeneity of the cell populations and EVs. Here, we assessed the therapeutic potential of a homogeneous population of clonal MSCs (cMSCs) and their EVs subpopulations in a mouse model of POF. MAIN METHODS: Granulosa cells were treated with cyclophosphamide (Cy) in the absence or presence of cMSCs, or cMSCs-derived EV subpopulations (EV20K and EV110K, isolated by high-speed centrifugation and differential ultracentrifugation, respectively). In addition, POF mice were treated with cMSCs, EV20K and/or EV110K. KEY FINDINGS: cMSC and both EV types protected granulosa cells from Cy-induced damage. Calcein-EVs were detected in the ovaries. Moreover, cMSC and both EV subpopulations significantly increased body weight, ovary weight, and the number of follicles, restored FSH, E2, and AMH levels, increased the granulosa cell numbers and restored the fertility of POF mice. cMSC, EV20K, and EV110K alleviated inflammatory-related genes expression (Tnf-α and IL8), and improved angiogenesis via upregulation expression of Vegf and Igf1 at the mRNA level and VEGF and αSMA at the protein level. They also inhibited apoptosis through the PI3K/AKT signaling pathway. SIGNIFICANCE: The administration of cMSCs and two cMSC-EVs subpopulations improved ovarian function and restored fertility in a POF model. EV20K is more cost-effective and feasible in terms of isolation, particularly in good manufacturing practice (GMP) facilities for treatment of POF patients in comparison with conventional EVs (EV110K).