Maternal voluntary physical exercise in the adult rat: evidence of exercise-associated differences in maternal food intake, and in brain effects on the progeny

Objectives: Maternal physical activity may impact behavioral and electrophysiological aspects of brain function, with short- and long-term effects on pre- and postnatal neurodevelopment of the offspring. This study evaluated in the rat the effects of maternal voluntary physical activity (MVPA) on food intake and weight gain in the dams, as well as anxiety-like behavior, short-term memory and the brain excitability-related phenomenon known as cortical spreading depression (CSD) on the mother-pup dyad.Methods: Female Wistar rats (n=33) were individually housed in cages containing a running wheel for a 30-days adaptation period before mating. Rats were classified as inactive (I); active (A) or very active (VA) according to the distance spontaneously travelled daily. During gestation, the dams continued to have access to the running wheel. Mothers and their respective pups (1 pup per mother) were evaluated in the open field test (OFT), object recognition test (ORT), elevated plus maze test (EPMT) and the CSD propagation features.Results: MVPA was directly associated with increased food intake and weight gain during gestation, and maternal anxiolytic-like behavioral responses in the OFT. Pups from VA mothers showed a high discrimination index for shape recognition memory (ORT) and decreased propagation velocities of CSD, when compared with the inactive group.Discussion: The data suggest that MVPA during the gestational period induces neuroplasticity and may modulate the brain functions in the mother-infant dyad in the rat.

Overview on brain function enhancement of Internet addicts through exercise intervention: Based on reward-execution-decision cycle

Internet addiction (IA) has become an impulse control disorder included in the category of psychiatric disorders. The IA trend significantly increased after the outbreak of the new crown epidemic. IA damages some brain functions in humans. Emerging evidence suggests that exercise exerts beneficial effects on the brain function and cognitive level damaged by IA. This work reviews the neurobiological mechanisms of IA and describes the brain function impairment by IA from three systems: reward, execution, and decision-making. Furthermore, we sort out the research related to exercise intervention on IA and its effect on improving brain function. The internal and external factors that produce IA must be considered when summarizing movement interventions from a behavioral perspective. We can design exercise prescriptions based on exercise interests and achieve the goal of quitting IA. This work explores the possible mechanisms of exercise to improve IA through systematic analysis. Furthermore, this work provides research directions for the future targeted design of exercise prescriptions.

Exercise on Striatal Dopamine Level and Anxiety-Like Behavior in Male Rats after 2-VO Cerebral Ischemia

The purpose of this study was to discuss the effect of voluntary wheel running on striatal dopamine levels and anxiety-like behavior in rats with global cerebral ischemia. The male Sprague-Dawley rats were signed on in this study and randomly divided into following 4 groups: Control group (C group), Sham group (S group), ischemia group (I group), and 3 weeks physical exercise before ischemia group (3RI group). The rats in the 3RI group were placed in a voluntary running wheel for three weeks to exercise. Then, the rats in I and 3RI groups received bilateral carotid artery ligation (2-VO) operation. The C and S group did not perform voluntary running exercise and the bilateral common carotid arteries of S group were exposed without ligation. In vivo microdialysis was used in conjunction with high performance liquid chromatography (HPLC) and electrochemical detection to ascertain the level of dopamine in the striatum. Elevated plus maze (EPM) and open field (OF) were used to test anxiety status at 24 hours and 7days after 2-VO cerebral ischemia. Meanwhile, gait and motor coordination evaluations were carried out to eliminate the influence of non-specific motor problems. The results indicated that cerebral ischemia instigate the increase of striatal dopamine in I group rats during acute cerebral ischemia. A 3-week voluntary wheel running significantly enhances the striatal dopamine before ischemia and obstructs a further increase of dopamine during acute cerebral ischemia in 3RI group rats. At 24 hours after ischemia, striatal dopamine returned to pre-ischemic levels in 3RI group. Striatal dopamine in I group were less than pre-ischemic levels at 7 days. Behavioral data indicated that 3-week voluntary wheel running promoted recovery of anxiety-like behavior and gait were not affected by 2-VO cerebral ischemia at 24 hours post-ischemia rats. Therefore, it can be concluded that 3-week physical exercise significantly increased the striatal dopamine and improved anxiety-like behavior by inhibiting the increase of dopamine during acute cerebral ischemia and suppressing the decrease of dopamine after 24 hours and 7 days cerebral ischemia.

Metabolic Syndrome and Vascular-Associated Cognitive Impairment: a Focus on Preclinical Investigations

PURPOSE OF REVIEW

Metabolic syndrome is associated with an increased risk of vascular cognitive impairment or, in the more extreme, vascular dementia. Animal models are used to investigate the relationship between pathology and behaviour. This review summarizes the latest understanding of the role of the hippocampus and prefrontal cortex in vascular cognitive impairment, the influence of inflammation in this association while also commenting on some of the latest interventions proposed.

RECENT FINDINGS

Models of vascular cognitive impairment and vascular dementia, whether they develop from an infarct or non-infarct base, demonstrate increased neuroinflammation, reduced neuronal function and deficits in prefrontal and hippocampal-associated cognitive domains. Promising new research shows agents and environmental interventions that inhibit central oxidative stress and inflammation can reverse both pathology and cognitive dysfunction. While preclinical studies suggest that reversal of deficits in vascular cognitive impairment models is possible, replication in patients still needs to be demonstrated.

Effects of acrobatic training on spatial memory and astrocytic scar in CA1 subfield of hippocampus after chronic cerebral hypoperfusion in male and female rats

Chronic cerebral hypoperfusion leads to neuronal loss in the hippocampus and spatial memory impairments. Physical exercise is known to prevent cognitive deficits in animal models; and there is evidence of sex differences in behavioral neuroprotective approaches. The aim of present study was to investigate the effects of acrobatic training in male and female rats submitted to chronic cerebral hypoperfusion. Males and females rats underwent 2VO (two-vessel occlusion) surgery and were randomly allocated into 4 groups of males and 4 groups of females, as follows: 2VO acrobatic, 2VO sedentary, Sham acrobatic and Sham sedentary. The acrobatic training started 45 days after surgery and lasted 4 weeks; animals were then submitted to object recognition and water maze testing. Brain samples were collected for histological and morphological assessment and flow cytometry. 2VO causes cognitive impairments and acrobatic training prevented spatial memory deficits assessed in the water maze, mainly for females. Morphological analysis showed that 2VO animals had less NeuN labeling and acrobatic training prevented it. Increased number of GFAP positive cells was observerd in females; moreover, males had more branched astrocytes and acrobatic training prevented the branching after 2VO. Flow cytometry showed higher mitochondrial potential in trained animals and more reactive oxygen species production in males. Acrobatic training promoted neuronal survival and improved mitochondrial function in both sexes, and influenced the glial scar in a sex-dependent manner, associated to greater cognitive benefit to females after chronic cerebral hypoperfusion.

Exercise Intervention Promotes the Growth of Synapses and Regulates Neuroplasticity in Rats With Ischemic Stroke Through Exosomes

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.

Protective multi‑target effects of DL‑3‑n‑butylphthalide combined with 3‑methyl‑1‑phenyl‑2‑pyrazolin‑5‑one in mice with ischemic stroke

DL-3-n-butylphthalide (NBP) and 3-methyl-1- phenyl-2-pyrazolin-5-one (edaravone) are acknowledged neuroprotective agents that protect against ischemic stroke. However, the underlying mechanisms of a combination therapy with NBP and edaravone have not yet been fully clarified. The aim of the present study was to explore whether the co-administration of NBP and edaravone had multi-target protective effects on the neurovascular unit (NVU) of mice affected by ischemic stroke. Male C57BL/6 mice were randomly divided into the following three groups: i) Sham operation control, ii) middle cerebral artery occlusion (MCAO) and reperfusion, iii) and MCAO/reperfusion with the co-administration of NBP (40 mg/kg) and edaravone (6 mg/kg) delivered via intraperitoneal injection at 0 and 4 h after reperfusion (NBP + edaravone). After ischemia and reperfusion, infarct volumes and neurological deficits were evaluated. The immunoreactivity of the NVU, comprising neurons, endothelial cells and astrocytes, was determined using immunofluorescence staining of neuronal nuclei (NeuN), platelet and endothelial cell adhesion molecule 1 (CD31) and glial fibrillary acidic protein (GFAP). Western blotting was used to detect the expression levels of apoptosis-related proteins. The infarct volume, neurological function scores and cell damage were increased in the MCAO group compared with the sham operation group. Furthermore, the MCAO mice had reduced NeuN and CD31 expression and increased GFAP expression compared with the sham group. By contrast, the NBP + edaravone group exhibited reduced cell damage and consequently lower infarct volume and neurological deficit scores compared with the MCAO group. The NBP + edaravone group exhibited increased NeuN and CD31 expression and decreased GFAP expression compared with the MCAO group. Furthermore, the expression levels of Bax and cleaved caspase-3 in the NBP + edaravone group were decreased significantly compared with the MCAO group, while the expression levels of Bcl-2 and mitochondrial cytochrome c were increased. In conclusion, the results of the present study demonstrated that NBP and edaravone effectively prevented ischemic stroke damage with multi-target protective effects. In addition, NBP + edaravone may be a promising combination therapy for ischemic stroke.

Physical exercise promotes brain remodeling by regulating epigenetics, neuroplasticity and neurotrophins

Exercise has been shown to have beneficial effects on brain functions in humans and animals. Exercise can improve memory and learning in age-related neurodegenerative diseases. In animal models, physical exercise regulates epigenetics, promotes synaptic plasticity and hippocampal neurogenesis, regulates the expression levels of neurotrophic factors, and improves cognitive function. Therefore, exercise is very important for brain rehabilitation and remodeling. The purpose of this review is to explore the mechanisms by which exercise exerts positive effects on brain function. This knowledge implies that physical exercise can be used as a non-drug therapy for neurological diseases.

Involuntary, forced or voluntary exercise can ameliorate the cognitive deficits by enhancing levels of hippocampal NMDAR1, pAMPAR1 and pCaMKII in a model of vascular dementia

Objectives: To investigate the effect on vascular dementia of involuntary exercise induced by functional electrical stimulation and of forced and voluntary exercise, focusing on the recovery of cognitive function and using a rat model of dementia.Methods: A demential model was created in Wistar rats who were then given forced exercise, allowed voluntary exercise (wheel running) or had exercise induced through functional electrical stimulation. Their responses were quantified using a Morris water maze and by measuring long-term potentiation in the hippocampus. Immunohistochemical staining was used to evaluate neurogenesis in the hippocampus and Nissl staining was applied to visualize viable neuron loss in the DG sector. In addition, the levels of NMDAR1, AMPAR1, pAMPAR1, pCaMKII, CaMKII, Bcl-2 and Bax in the hippocampus were assessed by western blotting.Results: All of the exercise groups showed a recovery of cognitive performance and improved long-term potentiation. The three modes of exercise all increased the number of DCX immunopositive cells and reduced losses of intact-appearing neurons in the hippocampal DG zones roughly equally. All proved about equally effective in increasing the levels of NMDAR1, pAMPAR1 and pCaMKII and increasing the Bcl-2/Bax ratio to protect neurons from apoptosis.Conclusion: Exercise induced by electrical stimulation has beneficial effects comparable to those of other types of exercise for alleviating the cognitive deficits of vascular dementia.

Intensive treadmill training promotes cognitive recovery after cerebral ischemia-reperfusion in juvenile rats

Rehabilitation training is routine for children who experience stroke, but its protective mechanism remains unclear. To study the effect of treadmill training intensity on hippocampal synaptic plasticity after cerebral ischemia, a model of middle cerebral artery occlusion (MCAO)/reperfusion was established in young rats to simulate childhood ischemic stroke. The rats were randomly allocated into five groups: sham operation, MCAO, low-intensity exercise and MCAO (5 m/min), medium-intensity exercise and MCAO (10 m/min), and high-intensity exercise and MCAO (15 m/min). Intervention was continued for 14 days, and a series of experimental tests were conducted. After MCAO, the juvenile rats exhibited a series of morphological and functional alterations, including changes in their neurobehavior and cerebral infarct volumes. Compared with control rats, MCAO rats had a longer escape latency and crossed fewer platforms in the water maze test and exhibited decreased hippocampal neuron density and Synapsin I and PSD95 expression. Furthermore, MCAO rats exhibited synapse morphology changes and abnormal serum levels of lactic acid and corticosterone. Treadmill training effectively reduced the neurobehavioral scores and cerebral infarction volumes, with medium-intensity training showing the best effect. Treadmill training shortened the escape latency, increased the number of platform crossings, and improved the spatial cognitive abilities of the rats, with the medium intensity training having the best effect on spatial learning/memory efficiency. Treadmill training increased the neuron density in the hippocampus, with the medium-intensity training resulting in the highest density. Treadmill training had a positive effect on the expression of Synapsin I and PSD95, with the medium-intensity training showing the strongest effect. Treadmill training improved the sub-microstructure synapse morphology, with the medium-intensity training demonstrating the best effect. Treadmill training increased the plasma levels of lactic acid and corticosterone, with the high-intensity training having the most obvious effect. Treadmill training can provide neuroprotection by promoting hippocampal synaptic plasticity, with medium-intensity training showing the most optimal effects.

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.

Potential Involvement of Adiponectin Signaling in Regulating Physical Exercise-Elicited Hippocampal Neurogenesis and Dendritic Morphology in Stressed Mice

Adiponectin, a cytokine secreted by mature adipocytes, proves to be neuroprotective. We have previously reported that running triggers adiponectin up-regulation which subsequently promotes generation of hippocampal neurons and thereby alleviates depression-like behaviors in non-stressed mice. However, under the stressing condition, whether adiponectin could still exert antidepressant-like effects following exercise remained unexplored. In this study, by means of repeated corticosterone injections to mimic stress insult and voluntary wheel running as physical exercise intervention, we examined whether exercise-elicited antidepressive effects might involve adiponectin's regulation on hippocampal neurogenesis and dendritic plasticity in stressed mice. Here we show that repeated injections of corticosterone inhibited hippocampal neurogenesis and impaired dendritic morphology of neurons in the dentate gyrus of both wild-type and adiponectin-knockout mice comparably, which subsequently evoked depression-like behaviors. Voluntary wheel running attenuated corticosterone-suppressed neurogenesis and enhanced dendritic plasticity in the hippocampus, ultimately reducing depression-like behaviors in wild-type, but not adiponectin-knockout mice. We further demonstrate that such proneurogenic effects were potentially achieved through activation of the AMP-dependent kinase (AMPK) pathway. Our study provides the first evidence that adiponectin signaling is essential for physical exercise-triggered effects on stress-elicited depression by retaining the normal proliferation of neural progenitors and dendritic morphology of neurons in the hippocampal dentate gyrus, which may depend on activation of the AMPK pathway.

Neuroprotective effect of different physical exercises on cognition and behavior function by dopamine and 5-HT level in rats of vascular dementia

The aim of the present study is to evaluate neuroprotective effect of different physical exercises on cognition and behavior function by dopamine and 5-HT in rats of vascular dementia. Forty Sprague-Dawley rats were enrolled in this study and randomly divided into following 5 groups: control group (C group, n = 8), vascular dementia group (VD group, n = 8), treadmill exercise and vascular dementia group (TE-VD group, n = 8), in-voluntary exercise and vascular dementia group (IE-VD group, n = 8), voluntary exercise and vascular dementia group (VE-VD group, n = 8). The rats in TE-VD, IE-VD and VE-VD groups were received different physical exercise interventions, treadmill exercise, voluntary running exercise, involuntary running exercise respectively, total 4 weeks. Next, the rats in VE-VD, IE-VD, TE-VD and VD groups were received bilateral common carotids arteries operation to create vascular dementia model. Then, we use a passive avoid test to evaluate cognition and open field test to evaluate cognition autonomic activity in each group. The level in hippocampal dopamine and 5-HT were detected by microdialysis coupled with high performance liquid chromatography. Behavior results demonstrated that: compared with C group, the cognition in VD group significantly decreased (p < 0.001); compared with VD group, the cognition in VE-VD, IE-VD and TE-VD groups were significantly increased (p < 0.001). However, there are no significant difference between VE-VD, IE-VD and TE-VD groups (p> 0.05). In addition, hippocampal dopamine and 5-HT level significantly decreased in VD group when compared with C group (p < 0.001); hippocampal dopamine and 5-HT level in VE-VD, IE-VD and TE-VD groups were significantly increased when compared with VD group (p < 0.05). However, there are no significant difference between VE-VD, IE-VD and TE-VD groups (p> 0.05). Therefore, we concluded that different physical exercises, included treadmill exercise, in-voluntary exercise and voluntary exercise, all can protect cognition by up-regulate dopamine and 5-HT level in rats of vascular dementia.

Physical exercise promotes astrocyte coverage of microvessels in a model of chronic cerebral hypoperfusion

BACKGROUND

Brain circulation disorders such as chronic cerebral hypoperfusion have been associated with a decline in cognitive function during the development of dementia. Astrocytes together with microglia participate in the immune response in the CNS and make them potential sentinels in the brain parenchyma. In addition, astrocytes coverage integrity has been related to brain homeostasis. Currently, physical exercise has been proposed as an effective intervention to promote brain function improvement. However, the neuroprotective effects of early physical exercise on the astrocyte communication with the microcirculation and the microglial activation in a chronic cerebral hypoperfusion model are still unclear. The aim of this study was to investigate the impact of early intervention with physical exercise on cognition, brain microcirculatory, and inflammatory parameters in an experimental model of chronic cerebral hypoperfusion induced by permanent bilateral occlusion of the common carotid arteries (2VO).

METHODS

Wistar rats aged 12 weeks were randomly divided into four groups: Sham-sedentary group (Sham-Sed), Sham-exercised group (Sham-Ex), 2VO-sedentary group (2VO-Sed), and 2VO-exercised group (2VO-Ex). The early intervention with physical exercise started 3 days after 2VO or Sham surgery during 12 weeks. Then, the brain functional capillary density and endothelial-leukocyte interactions were evaluated by intravital microscopy; cognitive function was evaluated by open-field test; hippocampus postsynaptic density protein 95 and synaptophysin were evaluated by western blotting; astrocytic coverage of the capillaries, microglial activation, and structural capillary density were evaluated by immunohistochemistry.

RESULTS

Early moderate physical exercise was able to normalize functional capillary density and reduce leukocyte rolling in the brain of animals with chronic cerebral hypoperfusion. These effects were accompanied by restore synaptic protein and the improvement of cognitive function. In addition, early moderate exercise improves astrocytes coverage in blood vessels of the cerebral cortex and hippocampus, decreases microglial activation in the hippocampus, and improves structural capillaries in the hippocampus.

CONCLUSIONS

Microcirculatory and inflammatory changes in the brain appear to be involved in triggering a cognitive decline in animals with chronic cerebral ischemia. Therefore, early intervention with physical exercise may represent a preventive approach to neurodegeneration caused by chronic cerebral hypoperfusion.

Exercise training increases spatial memory via reducing contralateral hippocampal NMDAR subunits expression in intracerebral hemorrhage rats

OBJECTIVE

The aim of this study was to explore the effect of exercise training on spatial memory in rats with intracerebral hemorrhage (ICH) and to analyze its related neurobiological mechanisms.

METHODS

A total of 26 Sprague-Dawley rats were randomly divided into 3 groups: exercise (EX) group undergoing exercise training after ICH, model (MD) group and sham-operated (SM) group. The ICH rats model were induced by infusion of type I collagenase into caudate nucleus of rats. Morris water maze (MWM) test was performed at the same time in three groups to evaluate spatial memory in rats. All rats were sacrificed for evaluation of expression of N-methyl-d-aspartate receptor 1 (NR1) and N-methyl-d-aspartate receptor 2B (NR2B) in the CA3 region of the hippocampus by Western blot.

RESULTS

MWM test results showed that the spatial memory of MD group was significantly decreased compared to that of SM operation group (P<0.05), while exercise training significantly improved the spatial memory of rats with cerebral hemorrhage (P<0.05). Western blot analysis showed that exercise training significantly decreased the expression of NR1 and NR2B in CA3 region of the contralateral hippocampus (P<0.05), but there was no significant difference between MD and SM groups (P>0.05).

CONCLUSION

Exercise training improves the spatial memory in the rats with ICH via down-regulating NR1 and NR2B expression in CA3 region of the contralateral hippocampus.

Trace eyeblink conditioning is associated with changes in synaptophysin immunoreactivity in the cerebellar interpositus nucleus in guinea pigs

Synaptic plasticity plays a role during trace eyeblink conditioning (TEBC). Synaptophysin (Syn) is a major integral transmembrane protein, located particularly in the synaptic vesicles, and is considered a molecular marker of synapses. In addition, Syn immunoreactivity is an important indicator of synaptic plasticity. In the present study, we used immunohistochemical techniques to assess changes in Syn expression in the cerebellar interpositus nucleus (IN) of guinea pigs exposed to TEBC and pseudoconditioning. Additionally, we analyzed the relationship between Syn immunoreactivity and the percentage of trace-conditioned responses. Guinea pigs underwent trace conditioning or pseudoconditioning. Following two, six, or ten sessions, they were perfused and the cerebellum was removed for Syn immunohistochemical evaluation. After sessions 6 and 10, a significant increase in conditioned response (CR) percentage was observed in the trace-conditioned group, with the CR percentage reaching the learning criteria following session 10. Besides, for trace-conditioned animals, the Syn expression in IN was found significantly up-regulated after session 10 compared with pseudoconditioned ones. Our data suggest that the increase in Syn expression links to synaptic plasticity changes in the cerebellar IN and provides a histological substrate in the IN relating to TEBC training. The changing trend of Syn immunoreactivity in the IN is associated with CR percentage.

Translation of robot-assisted rehabilitation to clinical service: a comparison of the rehabilitation effectiveness of EMG-driven robot hand assisted upper limb training in practical clinical service and in clinical trial with laboratory configuration for chronic stroke

BACKGROUND

Rehabilitation robots can provide intensive physical training after stroke. However, variations of the rehabilitation effects in translation from well-controlled research studies to clinical services have not been well evaluated yet. This study aims to compare the rehabilitation effects of the upper limb training by an electromyography (EMG)-driven robotic hand achieved in a well-controlled research environment and in a practical clinical service.

METHODS

It was a non-randomized controlled trial, and thirty-two participants with chronic stroke were recruited either in the clinical service (n = 16, clinic group), or in the research setting (n = 16, lab group). Each participant received 20-session EMG-driven robotic hand assisted upper limb training. The training frequency (4 sessions/week) and the pace in a session were fixed for the lab group, while they were flexible (1-3 sessions/week) and adaptive for the clinic group. The training effects were evaluated before and after the treatment with clinical scores of the Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), Functional Independence Measure (FIM), and Modified Ashworth Scale (MAS).

RESULTS

Significant improvements in the FMA full score, shoulder/elbow and wrist/hand (P < 0.001), ARAT (P < 0.001), and MAS elbow (P < 0.05) were observed after the training for both groups. Significant improvements in the FIM (P < 0.05), MAS wrist (P < 0.001) and MAS hand (P < 0.05) were only obtained after the training in the clinic group. Compared with the lab group, higher FIM improvement in the clinic group was observed (P < 0.05).

CONCLUSIONS

The functional improvements after the robotic hand training in the clinical service were comparable to the effectiveness achieved in the research setting, through flexible training schedules even with a lower training frequency every week. Higher independence in the daily living and a more effective release in muscle tones were achieved in the clinic group than the lab group.

Elevated CRP at admission predicts post-stroke cognitive impairment in Han Chinese patients with intracranial arterial stenosis

OBJECTIVES

Elevated C-reactive protein (CRP) levels have been associated with cognitive deficits in certain patient populations, but whether this is also true of ischemic stroke patients is controversial. This study aims to examine the possible association between CRP concentration and post-stroke cognitive impairment (PSCI) in Han Chinese patients and to determine whether this association depends on intracranial arterial stenosis (ICAS).

METHODS

Patients with mild or moderate stroke admitted to a large regional medical center in Western China were consecutively enrolled in our study. Serum levels of CRP and ICAS severity were assessed at admission and cognitive status was assessed 6 months after stroke using the Six-Item Screener.

RESULTS

Of the 1116 patients included in our study, no association was observed between CRP levels at admission and cognitive performance at 6 months. However, among the subgroup of 311 patients with ICAS, a significant association did exist, and it persisted even after adjusting for potential confounders (OR 1.038, 95% CI 1.015-1.061). We did not find the same association in the subgroup of the patients without ICAS.

CONCLUSIONS

To our knowledge, this is the first study to explore the effects of CRP on PSCI in Han Chinese with ICAS. Our findings indicate that higher CRP levels at admission are associated with subsequent cognitive decline in Han Chinese patients with ICAS following ischemic stroke. Further studies in other ethnic groups are needed to validate the use of CRP to predict dementia in ICAS patients.

Forced treadmill exercise can induce stress and increase neuronal damage in a mouse model of global cerebral ischemia

Physical exercise is known to be a beneficial factor by increasing the cellular stress tolerance. In ischemic stroke, physical exercise is suggested to both limit the brain injury and facilitate behavioral recovery. In this study we investigated the effect of physical exercise on brain damage following global cerebral ischemia in mice. We aimed to study the effects of 4.5 weeks of forced treadmill running prior to ischemia on neuronal damage, neuroinflammation and its effect on general stress by measuring corticosterone in feces. We subjected C57bl/6 mice (n = 63) to either treadmill running or a sedentary program prior to induction of global ischemia. Anxious, depressive, and cognitive behaviors were analyzed. Stress levels were analyzed using a corticosterone ELISA. Inflammatory and neurological outcomes were analyzed using immunohistochemistry, multiplex electrochemoluminescence ELISA and Western blot. To our surprise, we found that forced treadmill running induced a stress response, with increased anxiety in the Open Field test and increased levels of corticosterone. In accordance, mice subjected to forced exercise prior to ischemia developed larger neuronal damage in the hippocampus and showed higher cytokine levels in the brain and blood compared to non-exercised mice. The extent of neuronal damage correlated with increased corticosterone levels. To compare forced treadmill with voluntary wheel running, we used a different set of mice that exercised freely on running wheels. These mice did not show any anxiety or increased corticosterone levels. Altogether, our results indicate that exercise pre-conditioning may not be beneficial if the animals are forced to run as it can induce a detrimental stress response.

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Enforcement to run results in anxious behavior.

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Mice that are forced to run have elevated levels of corticosterone.

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Enforcement to run results in more neuronal death in hippocampus.

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Corticosterone levels correlates with the neuronal damage in hippocampus.

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Increased corticosterone and anxiety is not seen in mice that run voluntarily.

The effects of hormones and physical exercise on hippocampal structural plasticity

The hippocampus plays an integral role in certain aspects of cognition. Hippocampal structural plasticity and in particular adult hippocampal neurogenesis can be influenced by several intrinsic and extrinsic factors. Here we review how hormones (i.e., intrinsic modulators) and physical exercise (i.e., an extrinsic modulator) can differentially modulate hippocampal plasticity in general and adult hippocampal neurogenesis in particular. Specifically, we provide an overview of the effects of sex hormones, stress hormones, and metabolic hormones on hippocampal structural plasticity and adult hippocampal neurogenesis. In addition, we also discuss how physical exercise modulates these forms of hippocampal plasticity, giving particular emphasis on how this modulation can be affected by variables such as exercise regime, duration, and intensity. Understanding the neurobiological mechanisms underlying the modulation of hippocampal structural plasticity by intrinsic and extrinsic factors will impact the design of new therapeutic approaches aimed at restoring hippocampal plasticity following brain injury or neurodegeneration.

Modulation of Synaptic Plasticity by Exercise Training as a Basis for Ischemic Stroke Rehabilitation

In recent years, rehabilitation of ischemic stroke draws more and more attention in the world, and has been linked to changes of synaptic plasticity. Exercise training improves motor function of ischemia as well as cognition which is associated with formation of learning and memory. The molecular basis of learning and memory might be synaptic plasticity. Research has therefore been conducted in an attempt to relate effects of exercise training to neuroprotection and neurogenesis adjacent to the ischemic injury brain. The present paper reviews the current literature addressing this question and discusses the possible mechanisms involved in modulation of synaptic plasticity by exercise training. This review shows the pathological process of synaptic dysfunction in ischemic roughly and then discusses the effects of exercise training on scaffold proteins and regulatory protein expression. The expression of scaffold proteins generally increased after training, but the effects on regulatory proteins were mixed. Moreover, the compositions of postsynaptic receptors were changed and the strength of synaptic transmission was enhanced after training. Finally, the recovery of cognition is critically associated with synaptic remodeling in an injured brain, and the remodeling occurs through a number of local regulations including mRNA translation, remodeling of cytoskeleton, and receptor trafficking into and out of the synapse. We do provide a comprehensive knowledge of synaptic plasticity enhancement obtained by exercise training in this review.