ABSTRACT
Aerobic training (AT), an effective form of cardiac rehabilitation, has been shown to be beneficial for cardiac repair and remodeling after myocardial infarction (MI). The p300/CBP-associated factor (PCAF) is one of the most important lysine acetyltransferases and is involved in various biological processes. However, the role of PCAF in AT and AT-mediated cardiac remodeling post-MI has not been determined. Here, we found that the PCAF protein level was significantly increased after MI, while AT blocked the increase in PCAF. AT markedly improved cardiac remodeling in mice after MI by reducing endoplasmic reticulum stress (ERS). In vivo, similar to AT, pharmacological inhibition of PCAF by Embelin improved cardiac recovery and attenuated ERS in MI mice. Furthermore, we observed that both IGF-1, a simulated exercise environment, and Embelin protected from H2O2-induced cardiomyocyte injury, while PCAF overexpression by viruses or the sirtuin inhibitor nicotinamide eliminated the protective effect of IGF-1 in H9C2 cells. Thus, our data indicate that maintaining low PCAF levels plays an essential role in AT-mediated cardiac protection, and PCAF inhibition represents a promising therapeutic target for attenuating cardiac remodeling after MI.
Subject(s)
Myocardial Infarction , Physical Conditioning, Animal , Ventricular Remodeling , p300-CBP Transcription Factors , Animals , p300-CBP Transcription Factors/metabolism , p300-CBP Transcription Factors/antagonists & inhibitors , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Mice , Ventricular Remodeling/drug effects , Ventricular Remodeling/physiology , Male , Mice, Inbred C57BL , Myocytes, Cardiac/metabolism , Endoplasmic Reticulum Stress/drug effectsABSTRACT
Overwhelming evidence has shown that aging is a significant risk factor for COVID-19-related hospitalizations, death and other adverse health outcomes. Particular T cell subsets that susceptible to aging and associated with COVID-19 disease severity requires further elucidation. Our study recruited 57 elderly patients with acute COVID-19 and 27 convalescent donors. Adaptive immunity was assessed across the COVID-19 severity spectrum. Patients underwent age-dependent CD4+ T lymphopenia, preferential loss of circulating T follicular regulatory cells (cTfh) subsets including cTfh-em, cTfh-cm, cTfh1, cTfh2, cTfh17 and circulating T follicular regulatory cells (cTfr), which regulated antibody production through different pathways and correlated with COVID-19 severity, were observed. Moreover, vaccination improved cTfh-cm, cTfh2, cTfr proportion and promoted NAb production. In conclusion, the elderly had gone through age-dependent cTfh subsets deficiency, which impeded NAb production and enabled aggravation of COVID-19 to critical illness, whereas SARS-CoV-2 vaccine inoculation helped to rejuvenate cTfh, cTfr and intensify NAb responses.
ABSTRACT
Exosomes (Exo) generated from mesenchymal stem cells (MSCs) have great therapeutic potential in ischemia-reperfusion treatment. For best therapeutic effect, high quality Exo product and effective delivery system are indispensable. In this study, we developed a new strategy for ischemia-reperfusion recovery by combining MSCs 3D (3D-MSC) culturing technology to generate Exo (3D-MSC-Exo) and microneedle for topical delivery. Firstly, primary MSCs from neonatal mice were isolated and 3D cultured with gelatin methacryloyl (GelMA) hydrogel to prepare 3D-MSC-Exo. The 3D-MSC showed better viability and 3D-MSC-Exo exhibited more effective effects of reducing neuroinflammation, inhibiting glial scarring, and promoting angiogenesis. Subsequently, the biocompatible GelMA was used to construct microneedles for 3D-Exo delivery (GelMA-MN@3D-Exo). The results demonstrated GelMA microneedles had excellent 3D-Exo loading capacity and enabled continuous 3D-Exo release to maintain effective therapeutic concentrations. Furthermore, the rat middle cerebral artery occlusion (MCAO) model was established to evaluate the therapeutic effect of GelMA-MN@3D-Exo in ischemia-reperfusion in vivo. Animal experiments showed that the GelMA-MN@3D-Exo system could effectively reduce the local neuroinflammatory reaction, promote angiogenesis and minimize glial scar proliferation in ischemia-reperfusion. The underlying reasons for the stronger neuroprotective effect of 3D-Exo was further studied using mass spectrometry and transcriptome assays, verifying their effects on immune regulation and cell proliferation. Taken together, our findings demonstrated that GelMA-MN@3D-Exo microneedle can effectively attenuate ischemia-reperfusion cell damage in the MCAO model, which provides a promising therapeutic strategy for ischemia-reperfusion recovery.
Subject(s)
Exosomes , Gelatin , Mesenchymal Stem Cells , Needles , Reperfusion Injury , Animals , Gelatin/chemistry , Mice , Rats , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Reperfusion Injury/prevention & control , Reperfusion Injury/therapy , Methacrylates/chemistry , Male , Disease Models, Animal , Hydrogels/chemistry , Rats, Sprague-Dawley , Infarction, Middle Cerebral Artery/therapyABSTRACT
Rationale: The large-scale genomic analysis classifies glioblastoma (GBM) into three major subtypes, including classical (CL), proneural (PN), and mesenchymal (MES) subtypes. Each of these subtypes exhibits a varying degree of sensitivity to the temozolomide (TMZ) treatment, while the prognosis corresponds to the molecular and genetic characteristics of the tumor cell type. Tumors with MES features are predominantly characterized by the NF1 deletion/alteration, leading to sustained activation of the RAS and PI3K-AKT signaling pathways in GBM and tend to acquire drug resistance, resulting in the worst prognosis compared to other subtypes (PN and CL). Here, we used the CRISPR/Cas9 library screening technique to detect TMZ-related gene targets that might play roles in acquiring drug resistance, using overexpressed KRAS-G12C mutant GBM cell lines. The study identified a key therapeutic strategy to address the chemoresistance against the MES subtype of GBM. Methods: The CRISPR-Cas9 library screening was used to discover genes associated with TMZ resistance in the U87-KRAS (U87-MG which is overexpressed KRAS-G12C mutant) cells. The patient-derived GBM primary cell line TBD0220 was used for experimental validations in vivo and in vitro. Chromatin isolation by RNA purification (ChIRP) and chromatin immunoprecipitation (ChIP) assays were used to elucidate the silencing mechanism of tumor suppressor genes in the MES-GBM subtype. The small-molecule inhibitor EPIC-0412 was obtained through high-throughput screening. Transmission electron microscopy (TEM) was used to characterize the exosomes (Exos) secreted by GBM cells after TMZ treatment. Blood-derived Exos-based targeted delivery of siRNA, TMZ, and EPIC-0412 was optimized to tailor personalized therapy in vivo. Results: Using the genome-wide CRISPR-Cas9 library screening, we found that the ERBIN gene could be epigenetically regulated in the U87-KRAS cells. ERBIN overexpression inhibited the RAS signaling and downstream proliferation and invasion effects of GBM tumor cells. EPIC-0412 treatment inhibited tumor proliferation and EMT progression by upregulating the ERBIN expression both in vitro and in vivo. Genome-wide CRISPR-Cas9 screening also identified RASGRP1(Ras guanine nucleotide-releasing protein 1) and VPS28(Vacuolar protein sorting-associated protein 28) genes as synthetically lethal in response to TMZ treatment in the U87-KRAS cells. We found that RASGRP1 activated the RAS-mediated DDR pathway by promoting the RAS-GTP transformation. VPS28 promoted the Exos secretion and decreased intracellular TMZ concentration in GBM cells. The targeted Exos delivery system encapsulating drugs and siRNAs together showed a powerful therapeutic effect against GBM in vivo. Conclusions: We demonstrate a new mechanism by which ERBIN is epigenetically silenced by the RAS signaling in the MES subtype of GBM. Restoration of the ERBIN expression with EPIC-0412 significantly inhibits the RAS signaling downstream. RASGRP1 and VPS28 genes are associated with the promotion of TMZ resistance through RAS-GDP to RAS-GTP transformation and TMZ efflux, as well. A quadruple combination therapy based on a targeted Exos delivery system demonstrated significantly reduced tumor burden in vivo. Therefore, our study provides new insights and therapeutic approaches for regulating tumor progression and TMZ resistance in the MES-GBM subtype.
Subject(s)
CRISPR-Cas Systems , Drug Resistance, Neoplasm , Exosomes , Glioblastoma , Temozolomide , Glioblastoma/genetics , Glioblastoma/pathology , Glioblastoma/drug therapy , Temozolomide/pharmacology , Temozolomide/therapeutic use , Humans , Drug Resistance, Neoplasm/genetics , CRISPR-Cas Systems/genetics , Cell Line, Tumor , Animals , Exosomes/metabolism , Exosomes/genetics , Mice , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Brain Neoplasms/drug therapy , Carcinogenesis/genetics , Carcinogenesis/drug effects , Mice, Nude , Xenograft Model Antitumor AssaysABSTRACT
Mitochondria play a crucial role in maintaining cellular energy supply and serve as a source of energy for repairing nerve damage following a stroke. Given that exercise has the potential to enhance energy metabolism, investigating the impact of exercise on mitochondrial function provides a plausible mechanism for stroke treatment. In our study, we established the middle cerebral artery occlusion (MCAO) model in Sprague-Dawley rats and implemented early exercise intervention. Neurological severity scores, beam-walking test score, and weight were used to evaluate neurological function. The volume of cerebral infarction was measured by MRI. Nerve cell apoptosis was detected by TUNEL staining. Mitochondrial morphology and structure were detected by mitochondrial electron microscopy. Mitochondrial function was assessed using membrane potential and ATP measurements. Western blotting was used to detect the protein expression of AMPK/PGC-1α/GLUT4. Through the above experiments, we found that early exercise improved neurological function in rats after MCAO, reduced cerebral infarction volume and neuronal apoptosis, promoted the recovery of mitochondrial morphology and function. We further examined the protein expression of AMPK/PGC-1α/GLUT4 signaling pathway and confirmed that early exercise was able to increase its expression. Therefore, we suggest that early exercise initiated the AMPK/PGC-1α/GLUT4 signaling pathway, restoring mitochondrial function and augmenting energy supply. This, in turn, effectively improved both nerve and body function in rats following ischemic stroke.
Subject(s)
AMP-Activated Protein Kinases , Mitochondria , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Physical Conditioning, Animal , Rats, Sprague-Dawley , Signal Transduction , Animals , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Signal Transduction/physiology , Male , AMP-Activated Protein Kinases/metabolism , Mitochondria/metabolism , Physical Conditioning, Animal/physiology , Physical Conditioning, Animal/methods , Infarction, Middle Cerebral Artery/metabolism , Infarction, Middle Cerebral Artery/therapy , Brain Ischemia/metabolism , Rats , Disease Models, Animal , Apoptosis/physiologyABSTRACT
Our previous studies have shown that early exercise intervention after stroke increases neural activity and synaptic plasticity and promotes the recovery of nerve fiber bundle integrity in the brain. However, the effect of exercise on the repair of myelin in the brain and the related mechanism are still unclear. In this study, we randomly divided the rats into three groups. Before and after 28 days of intervention, body weight, nerve function, the infarct size, white matter fiber bundle integrity, and nerve myelin structure and function were observed by measuring body weight, analysis of modified neurological severity score, CatWalk gait analysis, MRI, luxol fast blue staining, immunofluorescence, and transmission electron microscopy. Changes in the expression of proteins in the MEK/ERK pathway were assessed. The results showed that early exercise intervention resulted in neurological recovery, decreased the infarct volume and increased nerve fiber integrity, the myelin coverage area, myelin basic protein (MBP) fluorescence intensity expression, and myelin thickness. Furthermore, the expression level of MBP was significantly increased after early exercise intervention, while the expression levels of p-MEK1/2 and p-ERK1/2 were significantly reduced. In the cell study, MBP expression levels were significantly higher in the oxygen and glucose deprivation and administration group.In summary, early exercise intervention after stroke can promote myelin repair by inhibiting the MEK/ERK signaling pathway.
ABSTRACT
Vascular cognitive impairmentï¼VCIï¼ is a group of syndromes ranging from mild cognitive impairment to dementia caused by cerebrovascular disease, due to the lack of sensitivity and specific biomarkers, it is difficult to identify and diagnose early. Abnormal connectivity is observed in brain regions of patients with vascular cognitive disorders, locates mainly in the default mode networkï¼DMNï¼, and changes in their abnormal functional connectivity correlated with the degree of patients' cognitive impairment. Resting-state functional magnetic resonance imaging(rs-fMRI) is a commonly used method to detect the internal activity of the brain at resting state. The use of various rs-fMRI to study abnormal changes in the DMN in patients with VCI is useful to further investigate the pathogenesis of VCI and provide an objective basis for imaging. This article mainly reviews the application of rs-fMRI in the DMN in patients with VCI, bringing new perspectives for the correct diagnosis and assessment of VCI.
Subject(s)
Cognitive Dysfunction , Default Mode Network , Humans , Magnetic Resonance Imaging/methods , Cognitive Dysfunction/diagnostic imaging , Brain/diagnostic imaging , Brain MappingABSTRACT
OBJECTIVES: Tactile stimulation (TS) can promote neurogenesis and motor function recovery in rats with hypoxic-ischaemic brain injury, but the underlying mechanism is not clear. This study aimed to assess the effects of TS on neurological function in rats after cerebral ischaemia and explore the underlying mechanism. METHODS: Adult SD rats were randomly divided into a sham operation (SHAM) group, middle cerebral artery occlusion with tactile stimulation (TS-MCAO) group and middle cerebral artery occlusion with sedentary intervention (SED-MCAO) group. Twenty-four hours after MCAO, rats in the TS-MCAO group received TS for 20 min/d 5 d/w for 4 weeks. Cerebral blood flow (CBF), changes in body weight, behavioural scores, the infarct volume, corticospinal tract integrity, and neurochemical changes were measured, and Golgi-Cox staining, transmission electron microscopy and Western blotting were performed. RESULTS: CBF recovery was improved in the TS-MCAO group compared with the SED-MCAO group. Body weight and behavioural scores in the TS-MCAO group significantly changed after 28 days of intervention. After 14 and 28 days of intervention, the infarct volume decreased significantly, the ratios of fractional anisotropy increased and the ratios of apparent diffusion coefficient decreased, the ratios of Nacetylaspartate (NAA)/creatine (Cr) and glutamate (Glu)/ Cr increased. After 28 days of intervention, the complexity and density of dendrites, the number of synapses and the expression of synaptic plasticity-related proteins increased in the peri-infarct cortex. CONCLUSION: TS can improve motor performance in rats with cerebral ischaemia and the improvement is correlated with synaptic plasticity. This finding would be helpful to provide a rehabilitation program for patients following stroke.
Subject(s)
Brain Ischemia , Hypoxia-Ischemia, Brain , Stroke , Humans , Rats , Animals , Infarction, Middle Cerebral Artery/metabolism , Rats, Sprague-Dawley , Brain Ischemia/therapy , Stroke/therapy , Body Weight , Disease Models, AnimalABSTRACT
Motor impairment after stroke is generally caused by damage to the neural networks that control movement. Corticomuscular coherence (CMC) is a valid method to analyze the functional connectivity of the corticospinal pathway between the cerebral cortex and muscles. However, current studies on CMC in stroke patients only focused on the upper limbs. The functional connectivity between the brain and lower limbs in stroke patients has not been well studied. Therefore, twelve stroke patients and fifteen healthy controls were recruited and their electroencephalogram (EEG) and electromyogram (EMG) of Tibialis Anterior (TA), Lateral Gastrocnemius (LG) and Medial Gastrocnemius (MG) during unilateral static ankle dorsiflexion were recorded. We found the mean beta and gamma CMC values of Cz electrode of stroke patients were significantly lower than those of healthy controls (p < 0.05). The brain topography showed significant coherence in the center of the cerebral cortex in healthy controls, while there was no significant coherence in stroke patients. For clinical assessment, there was a significant positive correlation between CMC and lower limb Fugl-Meyer Assessment (FMA) for Cz-TA in beta band (r = 0.6296, p = 0.0282), Cz-LG in beta band (r = 0.6816, p = 0.0147), and Cz-MG in gamma band (r = 0.6194, p = 0.0317). A multiple linear regression model was established between CMC and lower limb FMA ( R2 = 0.6600 , p = 0.0280). Therefore, CMC between the cerebral cortex and lower limb muscles may be used as a new rehabilitation assessment biomarker in stroke.
Subject(s)
Ankle , Stroke , Humans , Ankle/physiology , Muscle, Skeletal/physiology , Electromyography/methods , ElectroencephalographyABSTRACT
Balance rehabilitation is exceedingly crucial during stroke rehabilitation and is highly related to the stroke patients' secondary injuries (caused by falling). Stroke patients focus on walking ability rehabilitation during the early stage. Ankle dorsiflexion can activate the brain areas of stroke patients, similar to walking. The combination of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) was a new method, providing more beneficial information. We extracted the event-related desynchronization (ERD), oxygenated hemoglobin (HBO), and Phase Synchronization Index (PSI) features during ankle dorsiflexion from EEG and fNIRS. Moreover, we established a linear regression model to predict Berg Balance Scale (BBS) values and used an eightfold cross validation to test the model. The results showed that ERD, HBO, PSI, and age were critical biomarkers in predicting BBS. ERD and HBO during ankle dorsiflexion and age were promising biomarkers for stroke motor recovery.
ABSTRACT
Background: Exosomes can activate microglia to modulate neural activity and synaptic plasticity by phagocytosis of neural spines or synapses. Our previous research found that an early 4-week exercise intervention in middle cerebral artery occlusion (MCAO) rats can promote the release of exosomes and protect the brain. This study intended to further explore the intrinsic mechanism of neuroprotection by exosome release after exercise. Methods: Rats were randomly divided into four groups: the sham operation (SHAM), middle cerebral artery occlusion (MCAO) with sedentary intervention (SED-MCAO), MCAO with exercise intervention (EX-MCAO), and MCAO with exercise intervention and exosome injection (EX-MCAO-EXO). Modified neurological severity score (mNSS), cerebral infarction volume ratio, microglial activation, dendritic complexity, and expression of synaptophysin (Syn) and postsynaptic density protein 95 (PSD-95) were detected after 28 days of intervention. Results: (1) The exercise improved body weight and mNSS score, and the survival state of the rats after exosome infusion was better. (2) Compared with the SED-MCAO group, the EX-MCAO (P = 0.039) and EX-MCAO-EXO groups (P = 0.002) had significantly lower cerebral infarct volume ratios (P < 0.05), among which the EX-MCAO-EXO group had the lowest (P = 0.031). (3) Compared with the SED-MCAO group, the EX-MCAO and EX-MCAO-EXO groups had a significantly decreased number of microglia (P < 0.001) and significantly increased process length/cell (P < 0.01) and end point/cell (P < 0.01) values, with the EX-MCAO-EXO group having the lowest number of microglia (P = 0.036) and most significantly increased end point/cell value (P = 0.027). (4) Compared with the SED-MCAO group, the total number of intersections and branches of the apical and basal dendrites in the EX-MCAO and EX-MCAO-EXO groups was increased significantly (P < 0.05), and the increase was more significant in the EX-MCAO-EXO group (P < 0.05). (5) The expression levels of Syn and PSD-95 in the EX-MCAO (P Syn = 0.043, P PSD-95 = 0.047) and EX-MCAO-EXO groups were significantly higher than those in the SED-MCAO group (P < 0.05), and the expression levels in the EX-MCAO-EXO group were significantly higher than those in the EX-MCAO group (P < 0.05). Conclusion: Early exercise intervention after stroke can inhibit the excessive activation of microglia and regulate synaptic plasticity by exosome release.
ABSTRACT
Electrical stimulation of the right median nerve can aid coma arousal after traumatic brain injury (TBI). This study aimed to confirm the efficacy further and explore possible mechanisms of right median nerve electrical stimulation (RMNS). Five comatose patients after severe TBI from May to September 2020 in the Tianjin Medical University General Hospital received RMNS for 2 weeks besides standard management. After the 2-week treatment, the mean Glasgow Coma Scale (GCS) and neurophysiological examination were used. We then investigated the alterations in microRNA (miRNA) expression in cerebrospinal fluid (CSF) by high-throughput whole transcriptome sequencing, analyzed the data by Gene Ontology (GO) and pathway analysis, and constructed the miRNA-target gene network. Patient awareness and brain function showed a more rapid increase after treatment. We also found 38 differently expressed miRNAs, 34 of which were upregulated and 4 downregulated. GO analysis showed a relation of these differentially expressed miRNAs with neuronal growth, repair, and neural signal transmission. The most highly correlated pathways were primarily associated with the tumor necrosis factor (TNF) signaling pathway and dopaminergic synapse. The application of RMNS effectively promoted early awakening in comatose patients with severe TBI. Moreover, differentially expressed miRNAs might reduce neuronal apoptosis and increase dopamine levels by regulating target gene expression, thus participating in the specific biological process after arousal therapy. Our study provided novel targets for further research on the molecular mechanisms of RMNS arousal treatment and a new way to treat neurotraumatic diseases.
Subject(s)
Brain Injuries, Traumatic , MicroRNAs , Brain Injuries, Traumatic/complications , Brain Injuries, Traumatic/genetics , Brain Injuries, Traumatic/metabolism , Coma/etiology , Coma/therapy , Glasgow Coma Scale , Humans , Median NerveABSTRACT
PURPOSE: Sarcopenia is a major health problem in community-dwelling elderly individuals. Hypertension is postulated to aggravate sarcopenia. The present study was performed to estimate the prevalence of and factors associated with sarcopenia among elderly individuals with hypertension. METHODS: This study involved 165 Chinese individuals with hypertension aged ≥60 years who were evaluated for sarcopenia using the Asian Working Group for Sarcopenia criteria. Data on their sociodemographic information, physical illnesses, and clinical and functional status were collected. RESULTS: The overall prevalence of sarcopenia among elderly individuals with hypertension was 20.2%. The factors significantly associated with sarcopenia were an age of ≥70 years (adjusted odds ratio (OR), 3.01; 95% confidence interval (CI), 1.17-5.39), diabetes (OR, 4.45; 95% CI, 1.32-11.16), osteoporosis (OR, 2.52; 95% CI, 1.13-5.37), drinking (OR, 3.28; 95% CI, 1.26-7.85), and a body mass index of 24.0 to 27.9 kg/m2 (OR, 0.74; 95% CI, 0.59-0.91). CONCLUSIONS: This study revealed a very high prevalence of sarcopenia among elderly individuals with hypertension (20.2%). Sarcopenia may be associated with advanced age, drinking, diabetes, the body mass index, and osteoporosis. The longitudinal relationship between clinic visits and sarcopenia should be further evaluated.
Subject(s)
Hypertension , Osteoporosis , Sarcopenia , Aged , Humans , Hypertension/complications , Hypertension/epidemiology , Independent Living , Osteoporosis/complications , Osteoporosis/epidemiology , Prevalence , Sarcopenia/epidemiologyABSTRACT
Hypoxia preconditioning is neuroprotective, but the therapeutic effects of intermittent hypoxia were not fully considered. The present study investigated the neuroprotective effect and mechanism of intermittent hypoxia on motor function after cerebral ischemia and explored alternative clinical treatment options. In total, 36 8-week-old male Sprague-Dawley rats were subjected to 60 min of transient middle cerebral artery occlusion (tMCAO) and then randomly divided into a sham-operated group (SHAM), tMCAO-sedentary group (SED), and tMCAO-intermittent hypoxia group (IH). The intervention was performed 1 week after tMCAO and lasted 4 weeks. Rats in the IH group were placed in an animal hypoxic chamber (altitude 5000 m and oxygen concentration of 13%) for 4 h/day and 7 days/week, and rats in the SED group were placed in a normoxic environment for 4 weeks. Body weights, neurological deficit scores, cerebral infarction volume ratios, gait analyses, mitochondrial structure, adenosine triphosphate (ATP) content and AMO-activated protein kinase (AMPK), peroxisome proliferator-activated receptor γ co-activator-1α (PGC-1α), and silencing regulatory protein 3 (Sirt3) expression in the peri-ischemic region brain tissues were detected during the intervention. Compared with the SED group, the body weight of the IH group gradually recovered, and the neurological deficit scores were significantly reduced (P < 0.05). The gait analysis results showed that the pressure of the affected paw and the maximum content area, swing speed, stride length, and other parameters were significantly restored (P < 0.05). The cerebral infarction volume ratio was significantly reduced (P < 0.01). Mitochondrial morphological structure damage in the peri-ischemic region brain tissues recovered, the number was significantly increased (P < 0.05), and the expression of AMPK, PGC-1α, and Sirt3 proteins (P < 0.05), and ATP content were significantly increased (P < 0.05). Intermittent hypoxia may activate the AMPK-PGC-1α-Sirt3 signaling pathway, promote mitochondrial biogenesis, repair mitochondrial ultrastructural damage, and improve mitochondrial function to reduce brain damage and promote motor function recovery in rats with cerebral ischemia.
Subject(s)
Brain Ischemia , Sirtuin 3 , AMP-Activated Protein Kinases/metabolism , Adenosine Triphosphate/metabolism , Animals , Cerebral Infarction/metabolism , Hypoxia/metabolism , Male , Mitochondria/metabolism , Rats , Rats, Sprague-Dawley , Sirtuin 3/metabolism , Transcription Factors/metabolismABSTRACT
The hybrid brain-computer interface (hBCI) combining motor imagery (MI) and steady-state visual evoked potential (SSVEP) has been proven to have better performance than a pure MI- or SSVEP-based brain-computer interface (BCI). In most studies on hBCIs, subjects have been required to focus their attention on flickering light-emitting diodes (LEDs) or blocks while imagining body movements. However, these two classical tasks performed concurrently have a poor correlation. Therefore, it is necessary to reduce the task complexity of such a system and improve its user-friendliness. Aiming to achieve this goal, this study proposes a novel hybrid BCI that combines MI and intermodulation SSVEPs. In the proposed system, images of both hands flicker at the same frequency (i.e., 30 Hz) but at different grasp frequencies (i.e., 1 Hz for the left hand, and 1.5 Hz for the right hand), resulting in different intermodulation frequencies for encoding targets. Additionally, movement observation for subjects can help to perform the MI task better. In this study, two types of brain signals are classified independently and then fused by a scoring mechanism based on the probability distribution of relevant parameters. The online verification results showed that the average accuracies of 12 healthy subjects and 11 stroke patients were 92.40 ± 7.45% and 73.07 ± 9.07%, respectively. The average accuracies of 10 healthy subjects in the MI, SSVEP, and hybrid tasks were 84.00 ± 12.81%, 80.75 ± 8.08%, and 89.00 ± 9.94%, respectively. The high recognition accuracy verifies the feasibility and robustness of the proposed system. This study provides a novel and natural paradigm for a hybrid BCI based on MI and SSVEP.
Subject(s)
Brain-Computer Interfaces , Evoked Potentials, Visual , Attention , Brain/physiology , Electroencephalography/methods , Humans , Movement/physiology , Photic Stimulation/methodsABSTRACT
Electroencephalogram (EEG) is a basic physiological signal of human body, which can effectively record the nervous system activities of the brain and contains rich information. The synchronization of EEG signals is not only the key to the exchange of information between different brain regions, but also reflects the neural activity of the brain, which in turn can infer people's cognitive activities. Therefore, studying the phase synchronization of EEG signals after stroke is of great significance for understanding the communication and neuroplasticity of neurons after brain injury. In this paper, the changes of EEG phase synchronization in bilateral, cyclical ankle movements alternately after stroke were studied by Hilbert transform. Ten stroke patients and six healthy adults participated in the test. The results showed that the inter-hemisphere phase synchronization index (inter-PSI) and the global PSI of patients were significantly lower than that of the healthy subjects during the task. The PSI between Cz and the affected sensory cortex associated with lower limb movements was also significantly lower than that in the control group. There was a significant negative correlation between National Institutes of Health Stroke Scale (NIHSS) and cortical synchronization. The above results indicated that PSI under ankle alternating movements may be used as a new biomarker to evaluate the recovery of patients' brain neurons.
Subject(s)
Ankle , Stroke , Adult , Brain , Cortical Synchronization , Electroencephalography , Humans , United StatesABSTRACT
Balance problems are the main sequelae of stroke, which increases the risk of falling. The assessment of balance ability can guide doctors to formulate rehabilitation plans, thereby reducing the risk of falls. Studies have reported the role of resting-state EEG during sitting in the motor assessment of the upper extremity and prognosis of stroke patients. However, the above research in the sitting posture lacks specificity in evaluating the balance ability of the lower limbs. Herein, this article investigated whether EEG was different in sitting and standing positions with different difficulty levels and validated the feasibility of EEG in assessing body balance ability. The resting-state EEG signals were collected from 11 stroke patients. The pairwise-derived brain symmetry index (pdBSI) was used to identify the differences in EEG-quantified interhemispheric cortical power asymmetry observable in healthy versus cortical and subcortical stroke patients by calculating the absolute value of the difference in power at each pair of electrodes. Subsequently, we computed the pdBSI over different frequency bands. Balance function was assessed using the BBS (Berg Balance Scale). Stroke survivors showed higher pdBSI (1-25 Hz) values in standing posture compared to sitting (p <0.05) and the pdBSI was significantly negatively correlated with BBS (r = -0.671, p =0.034). Additionally, the pdBSI within beta band was also significantly negatively correlated with BBS (r = -0.711, p=0.017). In conclusion, stroke brain asymmetry in standing posture was significantly more severe and the pdBSIs in 1-25Hz and beta hand were related to balance function. BBS and NIHSS was significantly negatively correlated (r = -0.701, p = 0.024), and NIHSS was significantly correlated with age (r = 0.822, p = 0.004). The present study suggests that stroke can seriously affect the body's balance ability. Compared with the sitting posture, the asymmetry of cortical energy in the standing posture can better assess the patient's balance ability.
Subject(s)
Standing Position , Stroke Rehabilitation , Brain , Humans , Postural Balance , PostureABSTRACT
Background: Stroke is the leading cause of death and disability. Exercise produces neuroprotection by improving neuroplasticity. Exercise can induce exosome production. According to several studies, exosomes are involved in repairing brain function, but the relationship and mechanism of exercise, exosomes, and neuroprotection have not been elucidated. This study intends to explore the relationship and potential mechanism by observing the changes in the exosome level, infarct volume, neurological function and behavioral scores, synapses, and corticospinal tract (CST). Methods: Rats were randomly divided into four groups: a sham operation (SHAM) group, middle cerebral artery occlusion (MCAO) with sedentary intervention (SED-MCAO) group, MCAO with exercise intervention (EX-MCAO) group, and MCAO with exercise intervention and exosome injection (EX-MCAO-EXO) group. The exercise intervention was started 1 day after MCAO and lasted for 4 weeks. All rats were assessed using the modified neurological severity score (mNSS). The levels of exosomes in serum and brain, gait analysis, and magnetic resonance scan were performed 1 and 4 weeks after the intervention. After 4 weeks of intervention, the number of synapses, synaptophysin (Syn), and postsynaptic density protein 95(PSD-95) expression was detected. Results: After 4 weeks of intervention, (1) the EX-MCAO and EX-MCAO-EXO groups showed higher serum exosome (p EX-MCAO = 0.000, p EX-MCAO-EXO = 0.000) and brain exosome (p EX-MCAO = 0.001, p EX-MCAO-EXO = 0.000) levels than the SED-MCAO group, of which the EX-MCAO group had the highest serum exosome (p = 0.000) and the EX-MCAO-EXO group had the highest brain exosome (p = 0.03) levels. (2) The number of synapses in the EX-MCAO (p = 0.032) and EX-MCAO-EXO groups (p = 0.000) was significantly higher than that in the SED-MCAO group. The EX-MCAO-EXO group exhibited a greater number of synapses than the EX-MCAO (p = 0.000) group. (3) The synaptic plasticity-associated proteins were expressed significantly higher in the EX-MCAO (p Syn = 0.010, p PSD-95 = 0.044) and EX-MCAO-EXO (p Syn = 0.000, p PSD-95 = 0.000) groups than in the SED-MCAO group, and the EX-MCAO-EXO group (p Syn = 0.000, p PSD-95 = 0.046) had the highest expression. (4) Compared with the SED-MCAO group, the EX-MCAO group had significantly improved infarct volume ratio (p = 0.000), rFA value (p = 0.000), and rADC (p = 0.000). Compared with the EX-MCAO group, the EX-MCAO-EXO group had a significantly improved infarct volume ratio (p = 0.000), rFA value (p = 0.000), and rADC value (p = 0.001). (5) Compared with the SED-MCAO group, the EX-MCAO group (p = 0.001) and EX-MCAO-EXO group (p = 0.000) had significantly lower mNSS scores and improved gait. (6) The brain exosome levels were negatively correlated with the mNSS score, infarct volume ratio, and rADC value and positively correlated with the rFA value, Syn, and PSD-95 expression. The serum and brain exosome levels showed a positive correlation. Conclusions: Exercise intervention increases the serum exosome level in MCAO rats, which are recruited into the brain, leading to improved synaptic growth and CST integrity, a reduced infarct volume, and improved neurological function and gait.
ABSTRACT
ABSTRACT: This study reports a case of motor and sensory function recovery after massive left cerebral infarction in a young man, along with preserved function of the injured hemisphere. He received early rehabilitation therapy in a nerval care unit within 1 wk of surgery, and the rehabilitation lasted for more than 3 yrs. When he gradually recovered from coma, his motor, sensory, and speech functions improved significantly. Two years later, he was able to live independently and returned to work. The findings of functional magnetic resonance imaging, diffusion tensor imaging, somatosensory evoked potential, and motor evoked potential confirmed that there was a strong connection between his right brain and the right limbs. Thus, early rehabilitation is a promising approach for restoring motor and sensory function after massive brain injury or extensive brain tissue damage.
Subject(s)
Cerebral Infarction/physiopathology , Functional Laterality/physiology , Neural Pathways/pathology , Recovery of Function/physiology , Sensation/physiology , Stroke Rehabilitation , Cerebral Infarction/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Treatment Outcome , Young AdultABSTRACT
BACKGROUND: Vascular cognitive impairment (VCI) is a common cognitive disorder caused by cerebrovascular disease, ranging from mild cognitive impairment to dementia. Studies have shown that aerobic exercise might alleviate the pathological development of VCI, and our previous study observed that aerobic exercise could alleviate VCI through NF-κB/miR-503/BDNF pathway. However, there are few studies on the mechanism. Therefore, it is of great significance to fill the gaps in the mechanism for the early diagnosis of VCI and the clinical prevention and treatment of vascular dementia. METHODS: CircRNA microarray analysis and quantitative real-time PCR were used to detect the expression of circRNA regulating synaptic be exocytosis 2 (RIMS2) (circRIMS2). Cell apoptosis was determined by TdT-mediated dUTP nick-end labeling (TUNEL) assay. The dual-luciferase reporter assay was performed to verify the interaction between circRIMS2 and miR-186, as well as miR-186 and BDNF. RNA pull-down assay detected the binding between circRIMS2 and miR-186. A VCI mouse model was established by repeated ligation of bilateral common carotid arteries (2VO). The lentiviral interfering vector was injected into the VCI mice through the lateral ventricle. The mice in the aerobic exercise group performed 30 min (12 m/min) running for 5 days a week. A Morris water maze test was performed after 4 weeks. RESULTS: The expression of circRIMS2 and BDNF in the serum of VCI patients was significantly reduced, miR-186 expression was increased, and the expression of circRIMS2 was increased in the 2VO group of mice undergoing aerobic exercise. The expression levels of circRIMS2 and BDNF in the oxygen and glucose deprivation-treated (OGD-treated) cells were decreased, the miR-186 expression and cell apoptosis were increased, while the effect was weakened after transfection with the lentiviral vector pLO-ciR-RIMS2. CircRIMS2 could bind to miR-186, and after interference with circRIMS2 in HT22 cells, the expression of miR-186 was increased. Besides, miR-186 could bind to BDNF, and BDNF expression was decreased because of the overexpression of miR-186 in HT22 cells. The expression level of BDNF in the pLO-ciR-RIMS2 group was increased, and apoptosis was decreased, but the miR-186 mimic weakened the effect of pLO-ciR-RIMS2. Aerobic exercise could shorten the average time that mice reached the platform in the Morris water maze, increase the expression level of circRIMS2 and BDNF, reduce miR-186 expression, and inhibit neuronal apoptosis. However, the interference with circRIMS2 weakened this effect. CONCLUSION: The expression of circRIMS2 was down-regulated in VCI and aerobic exercise reduced neuronal apoptosis, and circRIMS2 improved VCI through the circRIMS2/miR-186/BDNF axis.