Treadmill exercise ameliorates nicotine withdrawal-induced symptoms

From gains to gaps? How Selective Androgen Receptor Modulator (SARM) YK11 impact hippocampal function: In silico, in vivo, and ex vivo perspectives

Selective Androgen Receptor Modulators (SARMs), particularly (17α,20E)-17,20-[(1-methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic-acid-methyl-ester (YK11), are increasingly popular among athletes seeking enhanced performance. Serving as an Androgen Receptor (AR) agonist, YK11 stimulates muscle growth while inhibiting myostatin. Our study delved into the impact of YK11 on the rat hippocampus, analyzing potential alterations in neurochemical mechanisms and investigating its synergistic effects with exercise (EXE), based on the strong relationship between SARM users and regular exercise. Utilizing Physiologically Based Pharmacokinetic (PBPK) modeling, we demonstrated YK11 remarkable brain permeability, with molecular docking analysis revealing YK11 inhibitory effects on 5-alpha-reductase type II (5αR2), suggesting high cell bioavailability. Throughout a 5-week experiment, we divided the animals into the following groups: Control, YK11 (0.35 g/kg), EXE (swimming exercise), and EXE + YK11. Our findings showed that YK11 displayed a high binding affinity with AR in the hippocampus, influencing neurochemical function and modulating aversive memory consolidation, including the downregulation of the BDNF/TrkB/CREB signaling, irrespective of EXE combination. In the hippocampus, YK11 increased pro-inflammatory IL-1β and IL-6 cytokines, while reducing anti-inflammatory IL-10 levels. However, the EXE + YK11 group counteracted IL-6 effects and elevated IL-10. Analysis of apoptotic proteins revealed heightened p38 MAPK activity in response to YK11-induced inflammation, initiating the apoptotic cascade involving Bax/Bcl-2/cleaved caspase-3. Notably, the EXE + YK11 group mitigated alterations in Bcl-2 and cleaved caspase-3 proteins. In conclusion, our findings suggest that YK11, at anabolic doses, significantly alters hippocampal neurochemistry, leading to impairments in memory consolidation. This underscore concerns about the misuse risks of SARMs among athletes and challenges common perceptions of their minimal side effects.

Vitamin B12 reversed anxiety and depression induced by adolescent nicotine withdrawal through alteration the inflammatory, oxidative and serotoninergic profiles in male rats

BACKGROUND

The present study aims to assess the effect of vitamin B12 (Vit B12) on depression-like behavior caused by nicotine (Nic) withdrawal, which is more likely due to the anxiogenic effect of Nic in adolescent male rats, through assessing behavioral and biochemical analysis.

METHODS

Adolescent male rats were divided into vehicle (received normal saline), and experimental groups that received Nic (2 mg/kg, intraperitoneally (i.p.)) for three consecutive weeks and after that, the group that received normal saline was divided into two groups, one of which returned to a regular diet, and the second one received Vit B12 (1.5 mg/kg). The Nic group was divided into five groups, one of which received bupropion (Bup, 20 mg/kg), three of which received different doses of Vit B12 (0.5, 1, and 1.5 mg/kg), and the last one returned to a normal diet without treatment, which was considered as the withdrawal period.

RESULTS

Behavioral analysis showed that Nic withdrawal induced anxiety and depression. Vit B12 and Bup reduced anxiety and depression induced by Nic withdrawal. The biochemical analysis demonstrated the more activity of oxidative stress factors and pro-inflammatory cytokines in which Nic was administered, whereas both Vit B12 and Bup reversed the results and improved the activity of both antioxidant and anti-inflammatory parameters. Furthermore, both serum and cortical Vit B12 levels dramatically decreased in nicotine group, whereas treatment with both Vit B12 and Bup as desirable treatments corrected Vit B12 levels.

CONCLUSION

According to the present findings, the results revealed that Vit B12 is comparable with Bup in attenuation of Nic withdrawal symptoms. In addition, both Bup and Vit B12 improved the decreased serum and cortical levels of Vit B12, which caused by nicotine. Administration of Vit B12 in normal animals demonstrated better results in reducing antioxidant and anti-inflammatory parameters, which explores new hope to introduce Vit B12 as a novel antioxidant and anti-inflammatory agent to treat not only withdrawal, but also other diseases related to the prominent role of oxidative stress or inflammatory pathways, such as Alzheimer's disease.

Comparison of periodontal status and salivary IL-15 and -18 levels in cigarette-smokers and individuals using electronic nicotine delivery systems

BACKGROUND

It is hypothesized that periodontal status is compromised and whole salivary (WS) interleukin (IL)-15 and IL-18 levels are higher among cigarette-smokers and electronic-nicotine-delivery-systems (ENDS)-users than never-smokers. The aim of the present case-control study was to compare the periodontal status and WS IL-15 and -18 levels among cigarette-smokers, ENDS-users and controls (never-smokers).

METHODS

Participants were divided into 4 groups as follows: Group-1:Current cigarette-smokers; Group-2:ENDS-users; Group-3:Never-smokers with periodontitis; and Group-4: Never-smokers without periodontitis. Demographic data was collected and plaque index (PI), gingival index (GI), probing-depth (PD), clinical attachment-loss (AL), and marginal bone loss (MBL) were measured. Number of missing teeth were recorded and WS IL-15 and IL-18 levels were determined. Group-comparisons were done and P < 0.01 was selected as an indicator of statistical analysis.

RESULTS

Nineteen, 18, 19 and 19 individuals were enrolled in groups 1, 2, 3 and 4, respectively. Scores of PI, clinical AL, PD, and number of missing-teeth were elevated in groups 1(P < 0.001), 2 (P < 0.001) and 3 (P < 0.001) than -4. Scores of PI, clinical AL, PD, MBL and missing teeth were comparable among patients in groups 1, 2 and 3. Levels of IL-15 and IL-18 were elevated in groups 1 (P < 0.001) and 2 (P < 0.001) than groups 3 and 4. The levels of IL-15 and -18 were higher in Group-3 than in Group-4 (P < 0.001).

CONCLUSION

Clinically, cigarette-smokers and never-smokers demonstrate similar periodontal statuses; however, WS immunoinflammatory biomarkers (IL-15 and -18) are elevated in these individuals than non-smokers.

The effect of aerobic exercises of different intensities on anxiety, cigarette addiction, sleep quality, and quality of life in former smokers

BACKGROUND

There is a worldwide struggle to quit smoking and prevent relapsing. Aerobic exercises are frequently utilized to aid in smoking cessation and prevent relapse.

AIMS

This study aimed to investigate the effects of aerobic exercises of different intensity on the level of anxiety, smoking addiction, and quality of sleep and life in former smokers.

METHODS

The study included 60 people aged 18 to 45 who had quit smoking within the previous month. Individuals were randomly assigned to control (CON), mild-intensity aerobic activity (MIA), and moderate-intensity aerobic activity (MoIA) groups. The MIA group did submaximal aerobic exercises at 40% of maximum heart rate (MHR), while the MoIA group did them at 60% of MHR for 8 weeks/3 days. Participants' anxiety levels were assessed using the Beck Anxiety Scale (BAS), smoking addiction was assessed using the Fagerström Test for Nicotine Dependence and Substance Craving Scale (SCS), sleep quality was assessed using the Pittsburgh Sleep Quality Index, and quality of life was assessed using the SF-36 Short Form Scale (SF-36).

RESULTS

The SCS score of the MoIA group declined more than the MIA and CON groups, and the MIA group had a lower sleep disturbance score than other groups when the influence of exercise training was assessed over time (p < 0.05). Aerobic exercise had no influence on SF-36 or BAS scores (p > 0.05).

CONCLUSIONS

The benefits of mild and moderate aerobic exercise on quality of life and anxiety are similar. However, mild-intensity aerobic exercises may be suitable for sleep difficulties while moderate-intensity aerobic exercises may be preferred for reducing smoking addiction.

Xiaoyaosan ethyl acetate fraction alleviates depression-like behaviors in CUMS mice by promoting hippocampal neurogenesis via modulating the IGF-1Rβ/PI3K/Akt signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaoyaosan (XYS), a representative and classic traditional Chinese medicine (TCM) prescription with function of dispersing stagnated liver and strengthening spleen, has been used for thousands of years to treat depression. XYS' anti-depression effect has been demonstrated both clinically and experimentally; however, the material basis for this effect has yet to be elucidated.

AIM OF THE STUDY

This study aimed to evaluate the impact and underlying action mechanism of XYS' antidepressant active component (Xiaoyaosan ethyl acetate fraction, XYSEF) against chronic unpredictable mild stress (CUMS)-induced depression-like behavior in mice.

MATERIALS AND METHODS

First, we established a behavioral despair depression mouse model to preliminarily determine the effective antidepressant dose of XYSEF. Then, we created a CUMS mouse model and used various classic behavioral tests, including SPT, ST, NFST, and TST, to assess XYSEF's antidepressant properties. IGF-1 levels in mouse serum and hippocampus were quantified using ELISA. The average optical density of Nissl bodies in the mouse hippocampal CA3 region was determined utilizing toluidine blue staining. Brdu and DCX expression in the hippocampal dentate gyrus (DG) was assayed using the immunofluorescence method. IGF-1Rβ, PI3K, p-PI3K, Akt, p-Akt, Caspase-3, and cleaved Caspase-3 protein levels in the hippocampus were determined with Western blot.

RESULTS

The behavioral despair mouse model findings showed that 9.1 and 40 g/kg of XYSEF both significantly shortened the immobility time of mice, suggesting that the effective dose range was 9.1-40 g/kg. Compared to the CUMS mouse model, XYSEF at 20 and 40 g/kg markedly increased the sucrose preference percentage in the SPT and grooming time in the ST, shortened the immobility time in the TST and the feeding latency in the NSFT, and reversed the downregulated IGF-1 content in mouse serum and hippocampus. In addition, XYSEF amplified the average optical density of Nissl bodies in the hippocampal CA3 region, promoted Brdu and DCX expression in DG, and diminished IGF-1Rβ, p-PI3K/PI3K, p-Akt/Akt, and cleaved Caspase-3/Caspase-3 protein levels in the hippocampi of CUMS mice.

CONCLUSION

XYSEF acted as an antidepressant in mice exhibiting CUMS-induced depression-like behaviors, possibly by promoting hippocampal neurogenesis, reducing neuronal apoptosis, and inhibiting the over-activation of the IGF-1Rβ/PI3K/Akt pathway.

Administration of brain-derived neurotrophic factor in the ventral tegmental area produces a switch from a nicotine nondependent D1R-mediated motivational state to a nicotine dependent-like D2R-mediated motivational state

Brain-derived neurotrophic factor (BDNF) has been implicated in the transition from a nondependent motivational state to a drug-dependent and -withdrawn motivational state. Chronic nicotine can increase BDNF in the rodent brain and is associated with smoking severity in humans; however, it is unknown whether this increased BDNF is linked functionally to the switch from a nicotine-nondependent to a nicotine-dependent state. We used a place conditioning paradigm to measure the conditioned responses to nicotine, showing that a dose of acute nicotine that nondependent male mice find aversive is found rewarding in chronic nicotine-treated mice experiencing withdrawal. A single BDNF injection in the ventral tegmental area (in the absence of chronic nicotine treatment) caused mice to behave as if they were nicotine-dependent and in withdrawal, switching the neurobiological substrate mediating the conditioned motivational effects from dopamine D1 receptors to D2 receptors. Quantification of gene expression of BDNF and its receptor, tropomyosin-receptor-kinase B (TrkB), revealed an increase in TrkB mRNA but not BDNF mRNA in the VTA in nicotine-dependent and -withdrawn mice. These results suggest that BDNF signaling in the VTA is a critical neurobiological substrate for the transition to nicotine dependence. The modulation of BDNF signaling may be a promising new pharmacological avenue for the treatment of addictive behavior.

Resistance Exercise Improves Spatial Learning Ability Through Phosphorylation of 5'-Adenosine Monophosphate-Activated Protein Kinase in Parkinson Disease Mice

Purpose

Exercise is a representative noninvasive treatment that can be applied to various diseases. We studied the effect of resistance exercise on motor function and spatial learning ability in Parkinson disease (PD) mice.

Methods

The rotarod test and beam walking test were conducted to evaluate the effect of resistance exercise on motor function, and the Morris water maze test was conducted to examine the effect of resistance exercise on spatial learning ability. The effect of resistance exercise on brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) expression and 5’-adenosine monophosphate-activated protein kinase (AMPK) phosphorylation was investigated by Western blot analysis. New cell generation was confirmed by immunohistochemistry for 5-bromo-2’-deoxyuridine.

Results

Resistance exercise improved coordination, balance, and spatial learning ability in PD mice. Resistance exercise enhanced new cell production, BDNF and TrkB expression, and AMPK phosphorylation in PD mice. The effect of such resistance exercise was similar to that of levodopa application.

Conclusions

In PD-induced mice, resistance exercise enhanced AMPK phosphorylation to increase BDNF expression and new neuron generation, thereby improving spatial learning ability. Resistance exercise is believed to help improve symptoms of PD.

Maternal Swimming Exercise During Pregnancy Improves Memory Through Enhancing Neurogenesis and Suppressing Apoptosis via Wnt/β-Catenin Pathway in Autistic Mice

Purpose

Wnt pathway is closely related to neurodevelopmental process associated with cognitive function. After administration of valproic acid to the pregnant mice, the effect of swimming exercise of pregnant mice on the memory, neuronal production, and apoptosis of pups was studied in relation with Wnt/β-catenin signaling pathway.

Methods

On day 12 of pregnancy, mice were injected subcutaneously with 400-mg/kg valproic acid. The pregnant mice in the control with swimming exercise group and in the valproic acid injection with swimming exercise group were allowed for swimming for 30 minutes one time per a day, repeated 5 days per a week, during 3 weeks. Step-through avoidance task and Morris water maze task for memory function, immunohistochemistry for 5-bromo-2’-deoxyuridine (BrdU)-positive cells and western blot for brain-derived neurotrophic factor (BDNF), Wnt, β-catenin, Bcl-2 related X protein (Bax), B-cell lymphoma 2 (Bcl-2), cleaved caspase-3 were carried out.

Results

Maternal swimming exercise during pregnancy improved memory function, increased BDNF expression, and neuronal proliferation in the valproic acid injected pups. Maternal swimming exercise during pregnancy suppressed Wnt expression and phosphorylation of β-catenin in the valproic acid injected pups. Maternal swimming exercise inhibited Bax and cleaved caspase-3 expression and increased Bcl-2 expression in the valproic acid injected pups.

Conclusions

Maternal swimming exercise during pregnancy improved memory function by increasing cell proliferation and inhibiting apoptosis through Wnt/β-catenin signaling cascade activation in the valproic acid injected pups. Maternal swimming exercise during pregnancy may have a protective effect on factors that induce autism in the fetus.

Aerobic exercise as a promising nonpharmacological therapy for the treatment of substance use disorders

Despite the prevalence and public health impact of substance use disorders (SUDs), effective long-term treatments remain elusive. Aerobic exercise is a promising, nonpharmacological treatment currently under investigation as a strategy for preventing drug relapse. Aerobic exercise could be incorporated into the comprehensive treatment regimens for people with substance abuse disorders. Preclinical studies of SUD with animal models have shown that aerobic exercise diminishes drug-seeking behavior, which leads to relapse, in both male and female rats. Nevertheless, little is known regarding the effects of substance abuse-induced cellular and physiological adaptations believed to be responsible for drug-seeking behavior. Accordingly, the overall goal of this review is to provide a summary and an assessment of findings to date, highlighting evidence of the molecular and neurological effects of exercise on adaptations associated with SUD.

Identification of the relationship between nicotine dependence levels and cessation fatigue

PURPOSE

This study aims to identify the relationship between nicotine dependence levels and cessation fatigue.

DESIGN AND METHODS

This descriptive study was conducted in a city located in the eastern part of Turkey between December 2019 and March 2020. The sample consisted of 107 students who met the research criteria. Data were collected using the sociodemographic form, the Fagerstrom test for nicotine dependence test, and the cessation fatigue scale (CFS).

FINDINGS

The CFS mean score was found to be significantly higher in women and in those who had high and very high nicotine dependence levels (p < 0.05). A positive and statistically significant relationship was found between cessation fatigue and nicotine dependence (p < 0.001). In addition, relationships were also found between cessation fatigue and variables, such as age, age of starting to smoke regularly, age of trying smoking for the first time, and the number of cigarettes smoked daily (p < 0.05).

PRACTICE IMPLICATIONS

This study detected a relationship between smoking cessation fatigue, and nicotine dependence. Studies have revealed that nursing practices on the struggle against smoking are effective. A better understanding of these processes could support nursing practices development.

Treadmill exercise in obese maternal rats during pregnancy improves spatial memory through activation of phosphatidylinositol 3-kinase pathway in the hippocampus of rat pups

Maternal nutrition is necessary for the growth of the fetus, and excessive intake of nutrients interferes with brain development in offspring. In the current study, the effect of treadmill running during pregnancy in obese maternal rats on spatial learning memory and spatial working memory in rat pups was investigated. Phosphorylation of phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and extracellular signal-regulated kinase 1 and 2 (ERK1/2) was also identified in rat pups. Female rats were divided into the normal diet group and the high-fat diet group for 7 weeks, including pregnancy and lactation. Maternal treadmill running was performed for 4 weeks. The born rat pups were classified into a control group, a treadmill exercise group, a high-fat diet group, a high-fat diet and treadmill exercise group according to the status of maternal rats. Radial 8-arm maze task for spatial learning memory and Morris water maze task for spatial working memory were done. Western blot analysis was conducted to determine the expressions of PI3K, Akt, ERK1/2. In the current results, maternal treadmill running during pregnancy improved spatial learning memory and spatial working memory in rat pups born to obese maternal rats. This improving effect of memory was due to the enhanced phosphorylation of PI3K, Akt, and ERK1/2 by treadmill running.

Application of stem cell biology in treating neurodegenerative diseases

BACKGROUND

The appropriate strategies are needed for stimulating the endogenous neurogenesis or introducing extrinsic neural progenitors, which could be harnessed as the regenerative resources for cueing the neurodegenerations. Adult neurogenesis is the endogenous continuing physiology in limited brain regions such as hippocampus, olfactory system, and hypothalamus. Besides adult neurogenesis, induced pluripotent stem cells (iPSCs) induced functional neurons could be another option for regenerative therapies.

OBJECTIVE

Current studies are trying to improve the adult neurogenesis and enable the iPSCs induced neurons into neural regeneration. Methods: Here in this review, we mainly introduced the recent progress in neural stem cell biology and its application in the treatment of the neurodegenerations. We main separated the strategy in summarizing the mediators and potential targets to promoting endogenous neural regeneration and transplantation of neural progenitors.

CONCLUSION

By collecting and comparing the advantages disadvantages between above-mentioned two strategies, we will offer the insight on future development of stem cell therapy in treating neurodegenerative patients.

Treadmill exercise in obese maternal rats during pregnancy improves short-term memory through neurogenesis in the hippocampus of rat pups

Maternal obesity is known to increase the likelihood of offspring becoming obese, high blood pressure, and other metabolic disorders. After inducing obesity, the effect of treadmill exercise in maternal rats during pregnancy on short-term memory was investigated in relation to neurogenesis in rat pups. Short-term memory was declined in rat pups born to obese maternal rats, and treadmill running during pregnancy alleviated short-term memory impairment in rat pups born to obese maternal rats. The number of doublecortin (DCX)-positive and 5-bro-mo-2′-deoxyuridine (BrdU)-positive cells in the hippocampal dentate gyrus was decreased in rat pups born to obese maternal rats. Treadmill running during pregnancy increased the number of DCX-positive and BrdU-positive cells in rat pups born to obese maternal rats. Expression of brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) in the hippocampus was decreased in the rat pups born to obese maternal rats. Treadmill running during pregnancy increased the expressions of BDNF and TrkB in rat pups born to obese maternal rats. Enhancing effect of short-term memory by treadmill exercise may be due to increased neurogenesis through activation of the BDNF-TrkB signaling pathway by treadmill exercise.

Effect of 4-Fluoro-N-(4-sulfamoylbenzyl) Benzene Sulfonamide on cognitive deficits and hippocampal plasticity during nicotine withdrawal in rats

Withdrawal from chronic nicotine has damaging effects on a variety of learning and memory tasks. Various Sulfonamides that act as carbonic anhydrase inhibitors have documented role in modulation of various cognitive, learning, and memory processing. We investigated the effects of 4-Fluoro-N-(4-sulfamoylbenzyl) Benzene Sulfonamide (4-FBS) on nicotine withdrawal impairments in rats using Morris water maze (MWM), Novel object recognition, Passive avoidance, and open field tasks. Also, Brain-derived neurotrophic factor (BDNF) profiling and in vivo field potential recording were assessed. Rats were exposed to saline or chronic nicotine 3.8 mg/kg subcutaneously for 14 days in four divided doses, spontaneous nicotine withdrawal was induced by quitting nicotine for 72 h (hrs). Animals received 4-FBS at 20, 40, and 60 mg/kg after 72 h of withdrawal in various behavioral and electrophysiological paradigms. Nicotine withdrawal causes a deficit in learning and long-term memory in the MWM task. No significant difference was found in novel object recognition tasks among all groups while in passive avoidance task nicotine withdrawal resulted in a deficit of hippocampus-dependent fear learning. Anxiety like behavior was observed during nicotine withdrawal. Plasma BDNF level was reduced during nicotine withdrawal as compared to the saline group reflecting mild cognitive impairment, stress, and depression. Withdrawal from chronic nicotine altered hippocampal plasticity, caused suppression of long-term potentiation (LTP) in the CA1 area of the hippocampus. Our results showed that 4-FBS at 40 and 60 mg/kg significantly prevented nicotine withdrawal-induced cognitive deficits in behavioral as well as electrophysiological studies. 4-FBS at 60 mg/kg upsurge nicotine withdrawal-induced decrease in plasma BDNF. We conclude that 4-FBS at 40 and 60 mg /kg effectively prevented chronic nicotine withdrawal-induced impairment in long term potentiation and cognitive performance.

Effects of swimming exercise on social isolation-induced memory impairment and apoptosis in old rats

Effect of swimming exercise on serotonin (5-hydroxytryptamine, 5-HT) expression and apoptosis in social isolation rats during old age was investigated. Rats in the old social isolation groups were housed alone per cage for 4 weeks. Rats in the swimming exercise groups were allowed to swim for 30 min once daily for 4 weeks. Morris water maze task determined spatial working memory and elevated plus maze test determined anxiety. Immunohistochemistry for tryptophan hydroxylase (TPH) and 5-HT in the dorsal raphe and for doublecortin (DCX) in the hippocampal dentate gyrus was conducted. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining in the hippocampal dentate gyrus was performed. Western blot analysis for Bax, Bcl-2, and cytochrome c in the hippocampus was conducted. Social isolation in rats of old age reduced spatial working memory and increased anxiety level. Swimming exercise enhanced spatial working memory and suppressed anxiety level. Social isolation in rats of old age inhibited TPH and 5-HT expression in dorsal rape. Swimming exercise increased TPH and 5-HT expression. Social isolation in rats of old age inhibited DCX-positive cells in the hippocampal dente gyrus. Swimming exercise increased DCX-positive cells. Social isolation in rats of old age increased TUNEL-positive cells, Bax and cytochrome c expression, and decreased Bcl-2 expression, which promoted apoptosis. Swimming exercise suppressed TUNEL-positive cells, Bax and cytochrome c expression, and increased Bcl-2 expression, which inhibited apoptosis. Swimming exercise improved 5-HT expression and suppressed apoptosis to alleviate anxiety and memory impairment during old age.

Treadmill exercise ameliorates social isolation-induced memory impairment by enhancing silent information regulator-1 expression in rats

The effect of treadmill exercise on the social isolation-induced memory impairment in relation with the silent information regulator-1 (SIRT-1) was investigated. The rats in the control groups lived four in the stan-dard cages for 8 weeks. The rats in the social isolation groups lived alone in the small cages for 8 weeks. The rats in the treadmill exercise groups were subjected to run on a treadmill for 30 min once a day for 8 weeks. We used step-through avoidance test for short-term memory and Morris water maze task for spatial working memory. Immunohisto-chemistry for SIRT-1 and western blot analysis for Bax, Bcl-2, cleaved caspase-3, brain-derived neurotrophic factor (BDNF), and tropomyosin receptor kinase B (TrkB) were performed. The rats in the social isolation group showed a decrease in short-term memory and spatial working memory. Treadmill exercise alleviated short-term memory and spatial working memory in the social isolation rats. SIRT-1 expression in the hippocampus was decreased in the rats of social isolation group. Treadmill exercise increased SIRT-1 expression in the social isolation rats. Bax expression was increased, Bcl-2 expression was decreased, and cleaved caspase-3 expression in the hippocampus was increased in the rats of social isolation group. Treadmill exercise decreased Bax expression, increased Bcl-2 expression, and decreased cleaved caspase-3 expression in the social isolation rats. Hippocampal BDNF and TrkB expression was decreased in the rats of social isolation group. Treadmill exercise increased BDNF and TrkB expression in the social isolation rats.

Treadmill Exercise Improves Motor Function and Short-term Memory by Enhancing Synaptic Plasticity and Neurogenesis in Photothrombotic Stroke Mice

Purpose

Thrombotic stroke is a type of ischemic stroke characterized by motor dysfunction and memory impairments. In the present study, the effect of treadmill exercise on motor function and short-term memory was evaluated in relation with synaptic plasticity in the mice with photothrombotic stroke.

Methods

Photothrombotic stroke was induced by cortical photothrombotic vascular occlusion. The mice in the treadmill exercise groups performed running on a motorized treadmill for 28 days. Motor function was determined using rota-rod test and foot fault test. Step-through avoidance task was conducted to evaluate short-term memory. Immunohistochemistry for 5-bromo-2′-deoxyuridine and doublecortin was conducted to detect new cell generation. Postsynaptic density protein 95, synaptophysin, brain-derived neurotrophic factor (BDNF), and tyrosine kinase B receptor (TrkB) were determined using western blot. The number of dendritic spines was determined using Golgi stain.

Results

Treadmill exercise improved motor function and short-term memory in mice with the photothrombotic stroke. The infarct size was reduced and the number of dendritic spines and expression of postsynaptic density protein 95 and synaptophysin in the peri-infarct cortex and hippocampus were increased by treadmill exercise in photothrombotic stroke mice. Treadmill exercise enhanced neurogenesis through increasing the expression of the hippocampal BDNF and TrkB in photothrombotic stroke mice.

Conclusions

Treadmill exercise improved motor function and short-term memory through increasing synaptic plasticity and neurogenesis in photothrombotic stroke mice. Treadmill exercise can be used as an effective treatment strategy to improve brain function related to stroke.

Effects of treadmill exercise on activity, short-term memory, vascular dysfunction in maternal separation rats

Maternal separation during early life causes psychiatric and neurologi-cal disorders such as anxiety and depression. Depression or anxiety is closely associated with memory impairment. The purpose of this study was to investigate the effect of treadmill exercise on activity, short-term memory, vascular dysfunction using maternal separation-induced de-pression model. Maternal separation started on 15-day-old rats. The rats in the maternal separation and fluoxetine injection group received intraperitoneal injection of 5 mg/kg of fluoxetine one time daily for 15 days from 21 to 35 days. The rats performed treadmill exercise once a day during 15 days from 21 to 35 days. There was low activity and short-term memory was decreased in the maternal separation rats. Treadmill exercise and fluoxetine injection increased activity and ameliorated memory impairment. The number of rat endothelial cells antigen-1 (RECA-1) of microvessels was decreased in the maternal separation rats. The number of RECA-1was increased by treadmill exercise and fluoxetine injection. Expression of matrix metalloproteinase-9 (MMP-9) was increased and expressions of zonula occludens-2 (ZO-2) and oc-cludin were decreased in the maternal separation rats. Treadmill exer-cise and fluoxetine injection suppressed MMP-9 expression and en-hanced ZO-2 and occludin expressions in the maternal separation rats. The present study shows treadmill exercise and antidepressant treat-ment ameliorates depressive symptom and short-term memory impair-ment by protecting from blood-brain barrier damage.

Swimming exercise ameliorates mood disorder and memory impairment by enhancing neurogenesis, serotonin expression, and inhibiting apoptosis in social isolation rats during adolescence

Social isolation during adolescence is associated with anxiety, depres-sion, and memory impairment. Exercise has been reported as a positive effect on brain function, especially hippocampus. The present study ex-amined the effect of swimming exercise on apoptosis, cell proliferation, and serotonin expression in social isolation rats during adolescence stage. Social isolation started at postnatal day 21 and continued for 6 weeks. The rats in the swimming group were forced to swim for 60 min once daily during 6 days per week for 6 consecutive weeks. The rats in the social isolation during adolescence showed anxiety, depression, short-term memory impairment. Social isolation facilitated apoptosis and inhibited cell proliferation and differentiation. Social isolation sup-pressed expression of serotonin, brain-derived neurotrophic factor, and tyrosine kinase B. Swimming exercise alleviated anxiety, depression, short-term impairment. Swimming exercise suppressed apoptosis, en-hanced neurogenesis, and increased serotonin expression. In our study, swimming exercise ameliorates mood disorder and memory impairment by enhancing neurogenesis and serotonin expression and inhibiting apoptosis in social isolation.