Different exercises can modulate the differentiation/maturation of neural stem/progenitor cells after photochemically induced focal cerebral infarction

Photochemically induced thrombosis combined with chronic restraint stress for modeling post-stroke depression in mice

Introduction

Post-stroke depression (PSD) is a prevalent neuropsychiatric disorder associated with impaired recovery in stroke survivors, potentially linked to dysregulation of brain-derived neurotrophic factor (BDNF). This study aimed to establish a novel animal model of PSD by integrating ischemic brain injury with chronic psychological stress.

Methods

Mice were subjected to photochemically induced thrombosis (PIT) to generate focal ischemic lesions in the parietal lobe, followed by chronic restraint stress (CRS) to simulate post-stroke psychological stress. Behavioral assessments (sucrose preference test, forced swim test, tail suspension test) and molecular analyses (BDNF, synaptophysin [SYP], interleukin-1 [IL-1], tumor necrosis factor-α [TNF-α]) were conducted to evaluate depressive-like phenotypes and neuroinflammatory markers.

Results

The PIT model produced consistent ischemic damage, with an average infarct area of 2.580 ± 0.426% in the parietal lobe. Mice exposed to PIT-CRS exhibited significant depressive-like behaviors, including reduced sucrose preference (p < 0.001), increased immobility time in the forced swim test (p = 0.056), and prolonged immobility in the tail suspension test (p = 0.168) compared to the Sham group. Molecular analyses revealed marked downregulation of BDNF (p = 0.004) and SYP (p = 0.074), alongside upregulated IL-1 (p = 0.024) and TNF-α (p = 0.368) levels in the PIT-CRS group.

Conclusion

The PIT-CRS model provides a comprehensive and reproducible platform for studying PSD. By integrating both ischemic injury and chronic stress, this model captures the multifaceted nature of PSD and offers valuable insights into its pathophysiology. Future research using this model could pave the way for the development of targeted therapies for PSD.

Exercise evaluation with metabolic and ventilatory responses and blood lactate concentration in mice

This study aimed to clarify the differential exercise capacity between 2-month-old and 10-month-old mice using an incremental running test. Metabolic and ventilatory responses and blood lactate concentration were measured to evaluate exercise capacity. We examined whether incremental running test results reflected metabolic and ventilatory responses and blood lactate concentration observed during the steady-state running test. Metabolic response significantly declined with age, whereas ventilatory response was similar between the groups. A low-intensity/moderate exercise load of 10/min in an incremental running test was performed on both mice for 30 min. They showed a characteristic pattern in ventilatory response in 10-month mice. The results of incremental running tests didn't necessarily reflect the steady-state metabolic and ventilatory responses because some parameters showed an approximation and others did not in incremental and steady-state tests, which changed with age. Our study suggests metabolic and ventilatory responses depending on age and provides basic knowledge regarding the objective and quantitative assessment of treadmill running in an animal model.

Application of a hospital–community–family trinity rehabilitation nursing model combined with motor imagery therapy in patients with cerebral infarction

BACKGROUND

Rehabilitation nursing is considered an indispensable part of the cerebral infarction treatment system. The hospital–community–family trinity rehabilitation nursing model can provide continuous nursing services across hospitals, communities, and families for patients.

AIM

To explore the application of a hospital–community–family rehabilitation nursing model combined with motor imagery therapy in patients with cerebral infarction.

METHODS

From January 2021 to December 2021, 88 patients with cerebral infarction were divided into a study (n = 44) and a control (n = 44) group using a simple random number table. The control group received routine nursing and motor imagery therapy. The study group was given hospital–community–family trinity rehabilitation nursing based on the control group. Motor function (FMA), balance ability (BBS), activities of daily living (BI), quality of life (SS-QOL), activation status of the contralateral primary sensorimotor cortical area to the affected side, and nursing satisfaction were evaluated before and after intervention in both groups.

RESULTS

Before intervention, FMA and BBS were similar (P > 0.05). After 6 months’ intervention, FMA and BBS were significantly higher in the study than in the control group (both P < 0.05). Before intervention, BI and SS-QOL scores were not different between the study and control group (P > 0.05). However, after 6 months’ intervention, BI and SS-QOL were higher in the study than in the control group (P < 0.05). Before intervention, activation frequency and volume were similar between the study and the control group (P > 0.05). After 6 months’ intervention, the activation frequency and volume were higher in the study than in the control group (P < 0.05). The reliability, empathy, reactivity, assurance, and tangibles scores for quality of nursing service were higher in the study than in the control group (P < 0.05).

CONCLUSION

Combining a hospital–community–family trinity rehabilitation nursing model and motor imagery therapy enhances the motor function and balance ability of patients with cerebral infarction, improving their quality of life.

Enriched Environment and Exercise Enhance Stem Cell Therapy for Stroke, Parkinson’s Disease, and Huntington’s Disease

Stem cells, specifically embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), induced pluripotent stem cells (IPSCs), and neural progenitor stem cells (NSCs), are a possible treatment for stroke, Parkinson’s disease (PD), and Huntington’s disease (HD). Current preclinical data suggest stem cell transplantation is a potential treatment for these chronic conditions that lack effective long-term treatment options. Finding treatments with a wider therapeutic window and harnessing a disease-modifying approach will likely improve clinical outcomes. The overarching concept of stem cell therapy entails the use of immature cells, while key in recapitulating brain development and presents the challenge of young grafted cells forming neural circuitry with the mature host brain cells. To this end, exploring strategies designed to nurture graft-host integration will likely enhance the reconstruction of the elusive neural circuitry. Enriched environment (EE) and exercise facilitate stem cell graft-host reconstruction of neural circuitry. It may involve at least a two-pronged mechanism whereby EE and exercise create a conducive microenvironment in the host brain, allowing the newly transplanted cells to survive, proliferate, and differentiate into neural cells; vice versa, EE and exercise may also train the transplanted immature cells to learn the neurochemical, physiological, and anatomical signals in the brain towards better functional graft-host connectivity.

Effect of Cell Therapy and Exercise Training in a Stroke Model, Considering the Cell Track by Molecular Image and Behavioral Analysis

The goal of this study is to see how combining physical activity with cell treatment impacts functional recovery in a stroke model. Molecular imaging and multimodal nanoparticles assisted in cell tracking and longitudinal monitoring (MNP). The viability of mesenchymal stem cell (MSC) was determined using a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay and bioluminescent image (BLI) after lentiviral transduction and MNP labeling. At random, the animals were divided into 5 groups (control-G1, and experimental G2-G5). The photothrombotic stroke induction was confirmed by local blood perfusion reduction and Triphenyltetrazolium chloride (TTC), and MSC in the G3 and G5 groups were implanted after 24 h, with BLI and near-infrared fluorescence image (NIRF) tracking these cells at 28 h, 2, 7, 14, and 28 days. During a 28-day period, the G5 also conducted physical training, whereas the G4 simply did the training. At 0, 7, 14, and 28 days, the animals were functionally tested using a cylinder test and a spontaneous motor activity test. MNP internalization in MSC was confirmed using brightfield and fluorescence microscopy. In relation to G1 group, only 3% of cell viability reduced. The G2–G5 groups showed more than 69% of blood perfusion reduction. The G5 group performed better over time, with a progressive recovery of symmetry and an increase of fast vertical movements. Up to 7 days, BLI and NIRF followed MSC at the damaged site, demonstrating a signal rise that could be connected to cell proliferation at the injury site during the acute phase of stroke. Local MSC therapy mixed with physical activity resulted in better results in alleviating motor dysfunction, particularly during the acute period. When it comes to neurorehabilitation, this alternative therapy could be a suitable fit.

Fast Independent Component Analysis Algorithm-Based Functional Magnetic Resonance Imaging in the Diagnosis of Changes in Brain Functional Areas of Cerebral Infarction

The aim of this study was to analyze the application value of functional magnetic resonance imaging (FMRI) optimized by the fast independent component correlation algorithm (ICA algorithm) in the diagnosis of brain functional areas in patients with lumbar disc herniation (LDH). An optimized fast ICA algorithm was established based on the ICA algorithm. 50 patients with cerebral infarction were selected as the research objects, and 30 healthy people were selected as the control group. The 50 patients from the observation group were examined by fMRI based on Fast ICA algorithm, while the control group was tested by fMRI based on the routine ICA algorithm. The performances of the two algorithms, the analysis results of the two groups of brain functional areas, cerebral blood flow (CBF), resting state functional connectivity (rsFC), behavioral data, and image data correlation of patients were compared. The results showed that the sensitivity, specificity, and accuracy of Fast ICA algorithm were 97.83%, 89.52%, and 96.27%, respectively, which in the experimental group were greatly better than the control group (88.73%, 72.19%, and 89.72%), showing statistically significant differences (P < 0.05). The maximum Dice coefficient of FAST ICA algorithm was 0.967, and FAST ICA algorithm was better obviously than the traditional ICA algorithm (P < 0.05). The cerebral blood flow of the healthy superior frontal gyrus (SFG) and healthy superior marginal gyrus (SMG) of the observation group with good motor function recovery were 1.02 ± 0.22 and 1.53 ± 0.61, respectively; both indicators showed an increasing trend, and those in the experimental group were much higher in contrast to the control group, showing statistically obvious differences (P < 0.05). Besides, the detection results of cerebral blood flow (CBF) in the healthy SFG and healthy SMG were negatively correlated with the results of connection test B. In summary, the fMRI based on the Fast ICA algorithm showed a good diagnostic effect in the changes of brain functional areas in patients with cerebral infarction. The experimental results showed that the cerebral blood flow in the brain area was related to motor or cognitive function. The results of this study provided a reliable reference for the examination and diagnosis of brain functional areas in patients with cerebral infarction.

Combination of Stem Cells and Rehabilitation Therapies for Ischemic Stroke

Stem cell transplantation with rehabilitation therapy presents an effective stroke treatment. Here, we discuss current breakthroughs in stem cell research along with rehabilitation strategies that may have a synergistic outcome when combined together after stroke. Indeed, stem cell transplantation offers a promising new approach and may add to current rehabilitation therapies. By reviewing the pathophysiology of stroke and the mechanisms by which stem cells and rehabilitation attenuate this inflammatory process, we hypothesize that a combined therapy will provide better functional outcomes for patients. Using current preclinical data, we explore the prominent types of stem cells, the existing theories for stem cell repair, rehabilitation treatments inside the brain, rehabilitation modalities outside the brain, and evidence pertaining to the benefits of combined therapy. In this review article, we assess the advantages and disadvantages of using stem cell transplantation with rehabilitation to mitigate the devastating effects of stroke.

Effects of Aerobic Exercise on Tau and Related Proteins in Rats with Photochemically-Induced Infarction

BACKGROUND

Recent evidence indicates brain ischemia is associated with accumulations of abnormal tau and related proteins. However, the effects of aerobic training on these proteins have not been evaluated.

OBJECTIVE

We aimed to evaluate the effect of aerobic exercise on the phosphorylation and acetylation of tau and on the expressions of tau related proteins in a rat stroke model and to compare the effects of aerobic exercise with those observed in our previous study on task specific training (TST).

METHODS

Twenty-four Sprague- Dawley rats with photothrombotic cortical infarction were used in the current study. The rehabilitation group (RG) received treadmill training 40 min/day for 28 days, whereas the sedentary group (SG) did not receive any type of training. Functional tests such as the single pellet reaching task, rotarod, and radial arm maze tests were performed weekly for 4 weeks post-infarction.

RESULTS

Levels of p-taus396 and p-AMPK were found to be lower in ipsilateral cortices in the RG than in the SG (p < 0.05). Levels of p-taus262, Ac-tau, p-GSK3βS9, p-Akt, p-Sin1, and p-P70-S6K were significantly lower in ipsilateral than in contralateral cortices in the RG (p < 0.05). Aerobic training also improved motor, balance, and memory functions.

CONCLUSION

Aerobic training inhibited the phosphorylation and acetylation of tau and modulated the expressions of tau related proteins after stroke by modifying the p70-S6K pathway and p-AMPK. By comparison with our previous study on the effects of TST, we have evidence to suggest that TST and aerobic exercise differ, although both types of rehabilitation inhibit tau phosphorylation and acetylation.

Voluntary wheel running promotes improvements in biomarkers associated with neurogenic activity in adult male rats

In rodents, hippocampal neurogenesis and synaptogenesis phenomena are affected by exercise. However, the role of exercise parameters such as intensity, duration, and mode on molecular mechanisms involved in these processes has not been elucidated. In this study, we evaluated the effects of different intensities and modes of running on the expression of genes contributing to neuronal differentiation and synapse formation in the hippocampus of adult male rats. Adult male Wistar rats (n = 24) were randomly divided into control, low-intensity running (LIR), high-intensity running (HIR), and the voluntary wheel running (WR) conditions. Changes in the expression of microRNA-124 (miR-124), microRNA-132 (miR-132), and their respective targets, were analyzed using quantitative RT-PCR and Western blotting techniques. Our results showed that WR compared to treadmill running increased miR-124 and miR-132 expression, while reducing the expression of their respective targets, glucocorticoid receptor (GR), SRY-Box 9 (SOX9), and GTP-activated protein P250 (P250GAP). Differences in expression levels were statistically significant (ps < 0.05), except for the expression of GR in HIR (P = 0.09). Moreover, the expression level of gene coding for the transcription factor cAMP-response element binding protein (CREB) was significantly higher in the WR group compared to the treadmill running groups (P = 0.001). Western blotting techniques indicated that the level of the CREB protein was higher in WR compared to the other groups qualitatively. These findings demonstrated a more dramatic effect for voluntary running on biomarkers that are associated with stimulating neurogenesis and synapse formation in the hippocampus of male rats compared with forced treadmill running. In addition, greater positive effects were observed for lower-intensity treadmill running as compared with high-intensity running.

Different exercises can modulate the differentiation/maturation of neural stem/progenitor cells after photochemically induced focal cerebral infarction

INTRODUCTION

Exercise therapies during rehabilitation significantly promote recovery from various deficits after cerebral infarction, which is mediated by neuronal plasticity with distinct inputs. Although adult neurogenesis can also be modulated by neuronal activity before synaptogenesis, how distinct exercises contribute to the neurological reorganization of the injured cerebral cortex remains unclear. In the present study, we aimed to elucidate the effects of different exercise therapies on motor recovery and neuronal reorganization after photochemically induced focal cerebral infarction.

METHODS

Here, we examined the effects of three different exercises-(a) forced lower-intensity and (b) higher-intensity treadmill exercises, and (c) voluntary exercise with wheel running-on motor recovery and adult neurogenesis in a rat model of focal cerebral infarction. Photochemically induced thrombosis (PIT) was used to generate focal infarction in rats that was mostly confined to their motor cortices.

RESULTS

Beam walking tests showed that recovery after PIT-induced cortical infarction differed in acute and chronic stages and was influenced by the type of exercise. Furthermore, forced low-intensity training had more positive effects on functional recovery than other exercises or control. To evaluate the production of newly generated cells including de novo neurogenesis, we performed lineage analysis with BrdU labeling and immunofluorescence experiments. Lower-intensity treadmill exercise increased the number of BrdU/NeuN colabeled cells, but not total BrdU-retaining or BrdU/Sox2-colabeled cells, in the peri-infarct region of the ipsilateral cortex. In contrast, high-intensity treadmill or voluntary exercises had the opposite effects.

CONCLUSIONS

These results suggest that neuronal maturation can be differently modulated by distinct exercises and that low-intensity treadmill exercise could result in more potent generation of mature neurons. This also suggests the possibility that the generation of neural stem/progenitor cells and differentiation might be modulated by rehabilitation-mediated neural plasticity.