miR-132-3p priming enhances the effects of mesenchymal stromal cell-derived exosomes on ameliorating brain ischemic injury

Abstract

Backgrounds/aims Mesenchymal stromal cell-derived exosomes (MSC-EXs) could exert protective effects on recipient cells by transferring the contained microRNAs (miRs), and miR-132-3p is one of angiogenic miRs. However, whether the combination of MSC-EXs and miR-132-3p has better effects in ischemic cerebrovascular disease remains unknown. Methods Mouse MSCs transfected with scrambler control or miR-132-3p mimics were used to generate MSC-EXs and miR-132-3p-overexpressed MSC-EXs (MSC-EXsmiR-132-3p). The effects of EXs on hypoxia/reoxygenation (H/R)-injured ECs in ROS generation, apoptosis, and barrier function were analyzed. The levels of RASA1, Ras, phosphorylations of PI3K, Akt and endothelial nitric oxide synthesis (eNOS), and tight junction proteins (Claudin-5 and ZO-1) were measured. Ras and PI3K inhibitors were used for pathway analysis. In transient middle cerebral artery occlusion (tMCAO) mouse model, the effects of MSC-EXs on the cerebral vascular ROS production and apoptosis, cerebral vascular density (cMVD), Evans blue extravasation, brain water content, neurological deficit score (NDS), and infarct volume were determined. Results MSC-EXs could deliver their carried miR-132-3p into target ECs, which functionally downregulated the target protein RASA1, while upregulated the expression of Ras and the downstream PI3K phosphorylation. Compared to MSC-EXs, MSC-EXsmiR-132-3p were more effective in decreasing ROS production, apoptosis, and tight junction disruption in H/R-injured ECs. These effects were associated with increased levels of phosphorylated Akt and eNOS, which could be abolished by PI3K inhibitor (LY294002) or Ras inhibitor (NSC 23766). In the tMCAO mouse model, the infusion of MSC-EXsmiR-132-3p was more effective than MSC-EXs in reducing cerebral vascular ROS production, BBB dysfunction, and brain injury. Conclusion Our results suggest that miR-132-3p promotes the beneficial effects of MSC-EXs on brain ischemic injury through protecting cerebral EC functions.

RETRACTED ARTICLE: Mesenchymal stem cell-derived exosome miR-542-3p suppresses inflammation and prevents cerebral infarction

“…Exosomes released by MSC have been found to contain 1927 proteins [ 20 ]. Proteomic analysis has proved that exosomes released by MSC have the effect of angiogenic paracrine, which indicates that exosomes released by MSC have the role and great potential in the treatment of ischemic tissue-related diseases [ 21 , 22 ].…”

Upregulation of Extracellular Vesicles-Encapsulated miR-132 Released From Mesenchymal Stem Cells Attenuates Ischemic Neuronal Injury by Inhibiting Smad2/c-jun Pathway via Acvr2b Suppression

“…Downregulation of miR-132 expression has been identified in MCAO mice and OGD-treated neurons, while upregulation of miR-132 has been speculated to diminish brain damage in MCAO mice and protect hippocampal neurons against OGD-induced apoptosis ( Mazziotti et al, 2017 ; Zuo et al, 2019 ). Moreover, the overexpression of miR-132 has been shown to contribute to enhanced neuronal viability ( Pan et al, 2020 ), decreased neuronal apoptosis, and elevated expression of Bcl-2 while downregulated levels of Bax as well as Caspase-3 have been reported following OGD treatment ( Sun et al, 2017 ). As described reported, BMSCs-released EVs can improve ischemic neuronal injury and EVs are abundant in miR-132 ( Xiao et al, 2018 ).…”

Oxidative Stress, Inflammation, and Autophagy: Potential Targets of Mesenchymal Stem Cells-Based Therapies in Ischemic Stroke

“…In their investigations, EVs from MSCs primed with miRNA- showed stronger neuroprotection effects than EVs lacking additional miRNA. Those miRNAs mainly participated in the reduction in neuroinflammation, ROS production, as well as BBB dysfunction, and promotion of angiogenesis (Xin et al, 2017a;Yang et al, 2018;Deng et al, 2019;Pan et al, 2020;Zhao et al, 2020). Intriguingly, Xin et al (2017b) proved that exosomes derived from miRNA-133b-overexpressed MSCs improved neural plasticity and functional recovery via stimulating the release of exosomes from oxygen and glucose deprivation (OGD)-treated astrocytes.…”