Obtained from the right cell-type, mesenchymal stromal cell (MSC)-derived small extracellular vesicles (sEVs) promote stroke recovery. Within this process, microvascular remodeling plays a central role. Herein, we evaluated the effects of MSC-sEVs on the proliferation, migration, and tube formation of human cerebral microvascular endothelial cells (hCMEC/D3) in vitro and on post-ischemic angiogenesis, brain remodeling and neurological recovery after middle cerebral artery occlusion (MCAO) in mice. In vitro, sEVs obtained from hypoxic (1% O2), but not ‘normoxic’ (21% O2) MSCs dose-dependently promoted endothelial proliferation, migration, and tube formation and increased post-ischemic endothelial survival. sEVs from hypoxic MSCs regulated a distinct set of miRNAs in hCMEC/D3 cells previously linked to angiogenesis, three being upregulated (miR-126-3p, miR-140-5p, let-7c-5p) and three downregulated (miR-186-5p, miR-370-3p, miR-409-3p). LC/MS–MS revealed 52 proteins differentially abundant in sEVs from hypoxic and ‘normoxic’ MSCs. 19 proteins were enriched (among them proteins involved in extracellular matrix–receptor interaction, focal adhesion, leukocyte transendothelial migration, protein digestion, and absorption), and 33 proteins reduced (among them proteins associated with metabolic pathways, extracellular matrix–receptor interaction, focal adhesion, and actin cytoskeleton) in hypoxic MSC-sEVs. Post-MCAO, sEVs from hypoxic MSCs increased microvascular length and branching point density in previously ischemic tissue assessed by 3D light sheet microscopy over up to 56 days, reduced delayed neuronal degeneration and brain atrophy, and enhanced neurological recovery. sEV-induced angiogenesis in vivo depended on the presence of polymorphonuclear neutrophils. In neutrophil-depleted mice, MSC-sEVs did not influence microvascular remodeling. sEVs from hypoxic MSCs have distinct angiogenic properties. Hypoxic preconditioning enhances the restorative effects of MSC-sEVs.

No abstract

Acupuncture treatment can inhibit the release of inflammatory cells after brain injury, then reduce immune injury, relieve muscle spasms and reduce muscular tension.

The aims of this study were to investigate the effect of neuromuscular electrical stimulation (NMES) combined with strengthening exercise on movement in children with spastic cerebral palsy (CP). One hundred children with spastic CP were randomly divided into a treatment group (NMES and strengthening exercise, n = 50) and a control group (only NMES, n = 50). We compared the Comprehensive Spasticity Scale (CSS) score, Gross Motor Function Measure (GMFM) score, and walking speed before treatment and 6 weeks and 3 months after treatment between the 2 groups. There was no difference in CSS score between the treatment and control groups before the therapy (12.0 ± 3.4 vs 12.3 ± 3.6), which decreased much more in the treatment group after 6 weeks (7.6 ± 3.0 vs 9.5 ± 2.8) and 3 months (7.4 ± 2.4 vs 9.4 ± 2.6) with significant differences ( P < .05). No difference in GMFM score was observed between the treatment and control groups before the therapy (44.5 ± 13.2 vs 44.0 ± 12.6), which increased much more in the treatment group after 6 weeks (70.6 ± 15.2 vs 56.7 ± 14.3) and 3 months (71.0 ± 16.4 vs 58.0 ± 15.6) with significant differences ( P < .05). The walking speed improved over time, which was the same before the treatment (0.43 ± 0.13 m/s vs 0.45 ± 0.14 m/s), and was significantly greater in the treatment group than that in the control group (6 weeks: 0.69 ± 0.15 m/s vs 0.56 ± 0.12 m/s, P < .05; 3 months: 0.72 ± 0.17 m/s vs 0.57 ± 0.18 m/s, P < .05). NMES combined with strengthening exercise was more effective than NMES alone in the recovery of spastic CP.

Until recently, the visualization of cerebral microvessels was hampered by the fact that only short segments of vessels could be evaluated in brain sections by histochemistry. These limitations have been overcome by light sheet microscopy, which allows the 3D analysis of microvasculature in cleared brains. A major limitation of light sheet microscopy is that antibodies do not sufficiently penetrate cleared brains. We herein describe a technique of reverse clearing and rehydration, which after microvascular network analysis allows brain sectioning and immunohistochemistry employing a broad set of antibodies. Performing light sheet microscopy on brains of mice exposed to intraluminal middle cerebral artery occlusion (MCAO), we show that in the early phase of microvascular remodeling branching point density was markedly reduced, more strongly than microvascular length. Brain infarcts in light sheet microscopy were sharply demarcated by their autofluorescence signal, closely corresponding to brain infarcts revealed by Nissl staining. Neuronal survival, leukocyte infiltration, and astrocytic reactivity could be evaluated by immunohistochemistry in rehydrated brains, as shown in direct comparisons with non-cleared brains. Immunohistochemistry revealed microthrombi in ischemic microvessels that were likely responsible for the marked branching point loss. The balance between microvascular thrombosis and remodeling warrants further studies at later time-points after stroke.