Administration of exosomes derived from mesenchymal stromal cells (MSCs) could improve some neurologic conditions by transferring functional biomolecules to recipient cells. Furthermore, exosomes ...from hypoxic progenitor cells exerted better therapeutic effects in organ injury through specific cargoes. However, there are no related reports about whether exosomes derived from MSCs or hypoxia‐preconditioned MSCs (PC‐MSCs) could prevent memory deficits in Alzheimer disease (AD). In this study, the exosomes derived from MSCs or PC‐MSCs were systemically administered to transgenic APP/PS1 mice. The expression of miR‐21 in MSCs was significantly increased after hypoxic treatment. Injection of exosomes from normoxic MSCs could rescue cognition and memory impairment according to results of the Morris water maze test, reduced plaque deposition, and Aβ levels in the brain; could decrease the activation of astrocytes and microglia; could down‐regulate proinflammatory cytokines (TNF‐α and IL‐1β); and could up‐regulate anti‐inflammatory cytokines (IL‐4 and ‐10) in AD mice, as well as reduce the activation of signal transducer and activator of transcription 3 (STAT3) and NF‐κB. Compared to the group administered exosomes from normoxic MSCs, in the group administered exosomes from PC‐MSCs, learning and memory capabilities were significantly improved; the plaque deposition and Aβ levels were lower, and expression of growth‐associated protein 43, synapsin 1, and IL‐10 was increased; and the levels of glial fibrillary acidic protein, ionized calcium‐binding adaptor molecule 1, TNF‐α, IL‐1β, and activation of STAT3 and NF‐κB were sharply decreased. More importantly, exosomes from PC‐MSCs effectively increased the level of miR‐21 in the brain of AD mice. Additionally, replenishment of miR‐21 restored the cognitive deficits in APP/PS1 mice and prevented pathologic features. Taken together, these findings suggest that exosomes from PC‐MSCs could improve the learning and memory capabilities of APP/PS1 mice, and that the underlying mechanism may lie in the restoration of synaptic dysfunction and regulation of inflammatory responses through regulation of miR‐21.—Cui, G.‐H., Wu, J., Mou, F.‐F., Xie, W.‐H., Wang, F.‐B., Wang, Q.‐L., Fang, J., Xu, Y.‐W., Dong, Y.‐R., Liu, J.‐R., Guo, H.‐D. Exosomes derived from hypoxia‐preconditioned mesenchymal stromal cells ameliorate cognitive decline by rescuing synaptic dysfunction and regulating inflammatory responses in APP/PS1 mice. FASEB J. 32, 654–668 (2018). www.fasebj.org
Exosomes are lipid-bilayer enclosed nano-sized vesicles that transfer functional cellular proteins, mRNA and miRNAs. Mesenchymal stem cells (MSCs) derived exosomes have been demonstrated to prevent ...memory deficits in the animal model of Alzheimer's disease (AD). However, the intravenously injected exosomes could be abundantly tracked in other organs except for the targeted regions in the brain. Here, we proposed the use of central nervous system-specific rabies viral glycoprotein (RVG) peptide to target intravenously-infused exosomes derived from MSCs (MSC-Exo) to the brain of transgenic APP/PS1 mice. MSC-Exo were conjugated with RVG through a DOPE-NHS linker.
RVG-tagged MSC-Exo exhibited improved targeting to the cortex and hippocampus after being administered intravenously. Compared with the group administered MSC-Exo, in the group administered RVG-conjugated MSC-Exo (MSC-RVG-Exo) plaque deposition and Aβ levels were sharply decreased and activation of astrocytes was obviously reduced. The brain targeted exosomes derived from MSCs was better than unmodified exosomes to improve cognitive function in APP/PS1 mice according to Morris water maze test. Additionally, although MSC-Exo injected intravenously reduced the expression of pro-inflammatory mediators TNF-α, IL-β, and IL-6, but the changes of anti-inflammatory factors IL-10 and IL-13 were not obvious. However, administration of MSC-RVG-Exo significantly reduced the levels of TNF-α, IL-β, and IL-6 while significantly raised the levels of IL-10, IL-4 and IL-13.
Taken together, our results demonstrated a novel method for increasing delivery of exosomes for treatment of AD. By targeting exosomes to the cortex and hippocampus of AD mouse, there was a significant improvement in learning and memory capabilities with reduced plaque deposition and Aβ levels, and normalized levels of inflammatory cytokines.
Taohong Siwu decoction (THSWD) is one of the classic prescriptions for promoting blood circulation and removing blood stasis. With the continuous in-depth excavation in basic and clinical research, ...it has been found that THSWD has made greater progress in the prevention and treatment of cardiovascular diseases. Mechanisms of the current studies have shown that it could prevent and treat the myocardial injury by inhibiting inflammatory reaction, antioxidant stress, inhibiting platelet aggregation, prolonging clotting time, anti-fibrosis, reducing blood lipids, anti-atherosclerosis, improving hemorheology and vascular pathological changes, regulating related signal pathways and other mechanisms to prevent and treat the myocardial injury, so as to protect cardiomyocytes and improve cardiac function. Many clinical studies have shown that THSWD is effective in the prevention and treatment of cardiovascular diseases related to myocardial injuries, such as coronary heart disease angina pectoris (CHD-AP), and myocardial infarction. In clinical practice, it is often used by adding and subtracting prescriptions, the combination of compound prescriptions and combinations of chemicals and so on. However, there are some limitations and uncertainties in both basic and clinical research of prescriptions. According to the current research, although the molecular biological mechanism of various active ingredients needs to be further clarified, and the composition and dose of the drug have not been standardized and quantified, this study still has exploration for scientific research and clinical practice. Therefore, this review mainly discusses the basic mechanisms and clinical applications of THSWD in the prevention and treatment of the myocardial injury caused by CHD-AP and myocardial infarction. The authors hope to provide valuable ideas and references for researchers and clinicians.
Alzheimer's disease (AD) is a common age-related neurodegenerative disease in the central nervous system and is the primary cause of dementia. It is clinically characterized by the memory impairment, ...aphasia, apraxia, agnosia, visuospatial and executive dysfunction, behavioral changes, and so on. Incidence of this disease was bound up with age, genetic factors, cardiovascular and cerebrovascular dysfunction, and other basic diseases, but the exact etiology has not been clarified. MicroRNAs (miRNAs) are small endogenous non-coding RNAs that were involved in the regulation of post-transcriptional gene expression. miRNAs have been extensively studied as noninvasive potential biomarkers for disease due to their relative stability in bodily fluids. In addition, they play a significant role in the physiological and pathological processes of various neurological disorders, including stroke, AD, and Parkinson's disease. MiR-155, as an important pro-inflammatory mediator of neuroinflammation, was reported to participate in the progression of β-amyloid peptide and tau via regulating immunity and inflammation. In this review, we put emphasis on the effects of miR-155 on AD and explore the underlying biological mechanisms which could provide a novel approach for diagnosis and treatment of AD.
Notoginsenoside R1 (NGR1) is the main monomeric component extracted from the dried roots and rhizomes of Panax notoginseng, and exerts pharmacological action against myocardial infarction (MI). Owing ...to the differences in compound distribution, absorption, and metabolism
in vivo
, exploring a more effective drug delivery system with a high therapeutic targeting effect is crucial. In the early stages of MI, CD11b-expressing monocytes and neutrophils accumulate at infarct sites. Thus, we designed a mesoporous silica nanoparticle-conjugated CD11b antibody with loaded NGR1 (MSN-NGR1-CD11b antibody), which allowed NGR1 precise targeted delivery to the heart in a noninvasively manner. By increasing targeting to the injured myocardium, intravenous injection of MSN-NGR1-CD11b antibody nanoparticle in MI mice improved cardiac function and angiogenesis, reduced cell apoptosis, and regulate macrophage phenotype and inflammatory factors and chemokines. In order to further explore the mechanism of NGR1 protecting myocardium, cell oxidative stress model and oxygen-glucose deprivation (OGD) model were established. NGR1 protected H9C2 cells and primary cardiomyocytes against oxidative injury induced by H
2
O
2
and OGD treatment. Further network pharmacology and molecular docking analyses suggested that the AKT, MAPK and Hippo signaling pathways were involved in the regulation of NGR1 in myocardial protection. Indeed, NGR1 could elevate the levels of
p
-Akt and
p
-ERK, and promote the nuclear translocation of YAP. Furthermore, LY294002 (AKT inhibitor), U0126 (ERK1/2 inhibitor) and Verteporfin (YAP inhibitor) administration in H9C2 cells indicated the involvement of AKT, MAPK and Hippo signaling pathways in NGR1 effects. Meanwhile, MSN-NGR1-CD11b antibody nanoparticles enhanced the activation of AKT and MAPK signaling pathways and the nuclear translocation of YAP at the infarcted site. Our research demonstrated that MSN-NGR1-CD11b antibody nanoparticle injection after MI enhanced the targeting of NGR1 to the infarcted myocardium and improved cardiac function. More importantly, our pioneering research provides a new strategy for targeting drug delivery systems to the ischemic niche.
NGR1 protected H9C2 cells and primary cardiomyocytes against oxidative injury induced by H
2
O
2
and OGD treatment. MSN-NGR1-CD11b antibody nanoparticle injection after MI enhanced the targeting of NGR1 to the infarcted myocardium and improved cardiac function by activating PIK3/AKT, MAPK/ERK and YAP signaling pathways.
Image 1
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CD11b antibody modification enhanced the target of Mesoporous silica nanoparticles to injured myocardium.
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NGR1 promoted the survival of H9C2 against oxidative stress injury through PIK3/AKT, MAPK/ERK and YAP signaling pathways.
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NGR1 protected neonatal and adult cardiomyocytes from H
2
O
2
and OGD induced oxidative stress damage.
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MSN-NGR1-CD11b antibody nanoparticles improved heart function by activating PIK3/AKT, MAPK/ERK and YAP signaling pathways.
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MSN-NGR1-CD11b antibody nanoparticles induced M2 polarization of macrophages and regulated the inflammatory factors.
Purpose. Our study is aimed at investigating the mechanism by which electroacupuncture (EA) promoted nerve regeneration by regulating the release of exosomes and exosome-mediated miRNA-21 (miR-21) ...transmission. Furthermore, the effects of Schwann cells- (SC-) derived exosomes on the overexpression of miR-21 for the treatment of PNI were investigated. Methods. A sciatic nerve injury model of rat was constructed, and the expression of miR-21 in serum exosomes and damaged local nerves was detected using RT-qPCR after EA treatment. The exosomes were identified under a transmission electron microscope and using western blotting analysis. Then, the exosome release inhibitor, GW4869, and the miR-21-5p-sponge used for the knockdown of miR-21 were used to clarify the effects of exosomal miR-21 on nerve regeneration promoted by EA. The nerve conduction velocity recovery rate, sciatic nerve function index, and wet weight ratio of gastrocnemius muscle were determined to evaluate sciatic nerve function recovery. SC proliferation and the level of neurotrophic factors were assessed using immunofluorescence staining, and the expression levels of SPRY2 and miR-21 were detected using RT-qPCR analysis. Subsequently, the transmission of exosomal miR-21 from SC to the axon was verified in vitro. Finally, the exosomes derived from the SC infected with the miR-21 overexpression lentivirus were collected and used to treat the rat SNI model to explore the therapeutic role of SC-derived exosomes overexpressing miR-21. Results. We found that EA inhibited the release of serum exosomal miR-21 in a PNI model of rats during the early stage of PNI, while it promoted its release during later stages. EA enhanced the accumulation of miR-21 in the injured nerve and effectively promoted the recovery of nerve function after PNI. The treatment effect of EA was attenuated when the release of circulating exosomes was inhibited or when miR-21 was downregulated in local injury tissue via the miR-21-5p-sponge. Normal exosomes secreted by SC exhibited the ability to promote the recovery of nerve function, while the overexpression of miR-21 enhanced the effects of the exosomes. In addition, exosomal miR-21 secreted by SC could promote neurite outgrowth in vitro. Conclusion. Our results demonstrated the mechanism of EA on PNI from the perspective of exosome-mediated miR-21 transport and provided a theoretical basis for the use of exosomal miR-21 as a novel strategy for the treatment of PNI.
Background
Migraine constitute a disorder characterized by recurrent headaches, and have a high prevalence, a high socio-economic burden and severe effects on quality of life. Our previous fMRI study ...demonstrated that some brain regions are functional alterations in migraineurs. As the function of the human brain is related to its structure, we further investigated white and gray matter structural alterations in migraineurs.
Methods
In current study, we used surface-based morphometry, voxel-based morphometry and diffusion tensor imaging analyses to detect structural alterations of the white matter and gray matter in 32 migraineurs without aura compared with 32 age- and gender-matched healthy controls.
Results
We found that migraineurs without aura exhibited significantly increased gray matter volume in the bilateral cerebellar culmen, increased cortical thickness in the lateral occipital-temporal cortex, decreased cortical thickness in the right insula, increased gyrification index in left postcentral gyrus, superior parietal lobule and right lateral occipital cortex, and decreased gyrification index in the left rostral middle frontal gyrus compared with controls. No significant change in white matter microstructure was found in DTI analyses.
Conclusion
The significantly altered gray matter brain regions were known to be associated with sensory discrimination of pain, multi-sensory integration and nociceptive information processing and were consistent with our previous fMRI study, and may be involved in the pathological mechanism of migraine without aura.
Progress in stem cell transplantation for the treatment of myocardial infarction is hampered by the poor retention and survival of the implanted cells. To enhance cell survival and differentiation ...and thereby improve the efficiency of stem cell therapy, we constructed a novel self-assembling peptide by attaching an RGDSP cell-adhesion motif to the self-assembling peptide RADA16. c-kit
pos/Nkx2.5
low/GATA4
low marrow-derived cardiac stem cells (MCSCs), which have a specific potential to differentiate into cardiomyocytes, were isolated from rat bone marrow. The cytoprotective effects of RGDSP scaffolds were assessed by exposure of MCSCs to anoxia
in vitro. The efficacy of transplanting MCSCs in RGDSP scaffolds was evaluated in a female rat MI model. The designer self-assembling peptide self-assembled into RGDSP nanofiber scaffolds under physiological conditions. RGDSP scaffolds were beneficial for the growth of MCSCs and protected them from apoptosis and necrosis caused by anoxia. In a rat MI model, cardiac function was improved and collagen deposition was markedly reduced in the group receiving MCSCs in RGDSP scaffolds compared with groups receiving MCSCs alone, RGDSP scaffolds alone or MCSCs in RADA16 scaffolds. There were more surviving MCSCs in the group receiving MCSCs in RGDSP scaffolds than in the groups receiving MCSCs alone or MCSCs in RADA16 scaffolds. Most of the Y chromosome-positive cells expressed cardiac troponin T and connexin43 (Cx-43). These results suggest that RGDSP scaffolds provide a suitable microenvironment for the survival and differentiation of MCSCs. RGDSP scaffolds enhanced the efficacy of MCSC transplantation to repair myocardium and improve cardiac function.
► Designer peptide RGDSP could self-assemble into nanofibers. ► RGDSP scaffold protected MCSCs against apoptosis and necrosis caused by anoxia. ► RGDSP scaffold provided a suitable microenvironment for the survival and differentiation of MCSCs. ► RGDSP scaffold enhanced the efficacy of MCSC transplantation to repair myocardium and improve cardiac function.
Aim: Studies have suggested that genetic and environmental factors do not account for all risks and mechanisms of intracranial atherosclerotic stenosis (ICAS). DNA methylation may play a role in the ...progression of ICAS.Methods: DNA methylation profiles of peripheral blood leucocytes from 7 patients with early-onset ICAS and 7 perfectly matched controls were interrogated for the first time using the Illumina Infinium Human MethylationEPIC BeadChip. Afterward, functional analysis for differentially methylated genes was conducted. In addition, pyrosequencing verification was performed in an independent cohort comprising 21 patients with early-onset ICAS and 21 age- and gender-matched controls.Results: A total of 318 cytosine-phosphate-guanine sites were found to be differentially methylated based on the established standards. Functional analysis annotated differentially methylated sites to atherosclerosis-related processes and pathways, such as the negative regulation of hydrolase activity (GO 0051346), type II diabetes mellitus (KEGG hsa04930), and the insulin signaling pathway (KEGG hsa04910). In addition, a differentially methylated site was also validated, cg22443212 in gene Rnf213, which showed significant hypermethylation in patients with early-onset ICAS compared with controls 59.56% (49.77%, 88.55%) vs. 44.65% (25.07%, 53.21%), respectively; P=0.010). Receiver operating characteristic curve analysis showed that the area under the curve value of cg22443212 was 0.744 (95% confidence interval, 0.586–0.866; P=0.002).Conclusions: We revealed that altered DNA methylation may play a role in the occurrence and development of ICAS. These results provided new epigenetic insights into ICAS.
Introduction: Multiple microRNAs (miRNAs) participate in the response to hypoxic/ischemic and ischemia-reperfusion events. However, the expression of these miRNAs in circulation from patients with ...acute ischemic stroke (AIS) receiving recanalization treatment has not been examined, and whether they are associated with the severity and outcome of stroke is still unknown. Materials and methods: In this prospective cohort study, plasma levels of miR-125b-5p, miR-15a-3p, miR-15a-5p, and miR-206 were measured at 24 hours after thrombolysis with or without endovascular treatment in 94 patients with AIS, as determined by qRT-PCR. Stroke severity was assessed based on National Institutes of Health Stroke Scale (NIHSS) score and infarct lesion. Intracranial haemorrhage (ICH) was recorded. An unfavorable outcome was defined as a modified Rankin Scale score greater than 2 at day 90 after stroke. Results: miR-125b-5p and miR-206 levels were correlated with NIHSS scores (P = .014 and P = .002) and cerebral infarction volumes (P = .025 and P = .030). miR-125b-5p levels were significantly higher in patients with an unfavorable outcome than in patients with a favorable outcome (P = .002) and showed good diagnostic accuracy in discriminating the presence of an unfavorable outcome (area under the curve .735, 95% confidence interval .623-.829, P < .001). No association was found between different miRNAs and ICH. Conclusions: In AIS patients after thrombolysis with or without endovascular treatment, miR-125b-5p is a novel prognostic biomarker highly associated with an unfavorable outcome. miR-125b-5p and miR-206 levels are associated with stroke severity.
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