Comparing activated brain regions between noisy and conventional galvanic vestibular stimulation using functional magnetic resonance imaging.

OBJECTIVE: Galvanic vestibular stimulation (GVS) enhances vestibular sensory inputs in vestibular afferents. However, it is unclear whether noisy and conventional GVS activate different regions of the brain. The purpose of this study was to investigate the differences in activated brain regions between those two interventions using functional MRI (fMRI). METHODS: Twenty-four healthy volunteers who met the inclusion/exclusion criteria were randomly assigned to the noisy GVS or conventional GVS groups. Brain activity was measured during stimulation and compared with that during resting fMRI. This study used a blocked design comprising four task-rest blocks, each consisting of a 30-s period of vestibular stimulation followed by a 30-s period of rest. We evaluated the differences in contrast images between the noisy and conventional GVS groups. RESULTS: The noisy GVS group showed significantly increased activation in the vestibular system-related brain regions, including the insula and central operculum. The conventional GVS group showed significant activity in multisensory areas, including the supramarginal gyrus, central operculum and opercular part of the inferior frontal gyrus. Thus, the noisy GVS group showed significantly increased activity in the insula, putamen and central operculum compared with the conventional GVS group. CONCLUSIONS: Noisy GVS could increase brain activity in the insular peripheral region compared to conventional GVS. Our results extend the literature about the importance of the stochastic resonance of noise addition for the vestibular system.

The Effects of Combining Transcranial Direct Current Stimulation and Gait Training with Functional Electrical Stimulation on Trunk Acceleration During Walking in Patients with Subacute Stroke.

OBJECTIVES: This study aimed to investigate whether the combination of transcranial direct current stimulation (tDCS) and gait training with FES affected walking speed and trunk accelerometry-based gait characteristics in patients with subacute stroke, compared with FES or tDCS gait training only. MATERIALS AND METHODS: Stroke patients (n = 34; female 15; mean age, 72.5 ± 11.2 years; mean days poststroke, 38.7) with resultant paresis in the lower extremity (mean Fugl-Meyer score, 25.5) were enrolled. Patients were randomly assigned to one of three groups: combined anodal tDCS and gait training with FES (tDCS+FES, n = 11), anodal tDCS with gait training (tDCS, n = 11), or combined sham tDCS and gait training with FES (FES, n = 12). Participants received the intervention for 20 minutes and a 40-minute conventional rehabilitative intervention daily for a week. Patients' walking ability was evaluated using walking speed, harmonic ratio (HR), autocorrelation coefficient (AC), and root mean square (RMS) along each axis using a wearable trunk accelerometer. RESULTS: The tDCS+FES group had a significantly greater change in AC in the anteroposterior axis and mediolateral axis than the FES and tDCS groups and FES group, respectively. There were no significant effects on walking speed or other parameters (HR and RMS) among the groups. CONCLUSIONS: The combination of anodal tDCS and gait training with FES improved the post-stroke patients' gait regularity than FES gait training intervention only. Thus, combined tDCS and FES gait training, as a novel intervention, could be an important therapeutic tool in improving walking performance.

Social anxiety tendency and autism spectrum disorder in Japanese adolescence.

BACKGROUND: In Japanese high schools, understanding of school non-attendance and students with developmental disabilities, including autism spectrum disorder (ASD), is gradually improving. On the other hand, few people recognize social anxiety disorder (SAD), the onset of which commences during youth. Social anxiety disorder and ASD share various overlapping characteristics but have different diagnostic criteria. The anxiety caused by these disorders sometimes appears as school non-attendance. This study examines the relationship between SAD, ASD, and history of school non-attendance in high school students. METHODS: One hundred and fifty-eight students at one Japanese high school that accepts school non- attending students were investigated. To understand the features of ASD and how it relates to SAD tendencies, the Liebowitz Social Anxiety Scale - Japanese (LSAS-J) and Autism-Spectrum Quotient - Japanese (AQ-J) were used. Based on the LSAS-J cutoff point, participants were divided into high and low anxiety groups and then data were compared between the two groups. Potential factors associated with a high-SAD trend were evaluated using multivariate logistic regression. RESULTS: The results showed that students with high ASD scores were more likely to have SAD and that a lack of "social skill," a subscale of ASD, was closely associated with a social anxiety trend. However, the relationship between school non-attendance and social anxiety could not be confirmed. CONCLUSIONS: Focusing on the lack of social skills in ASD may provide an opportunity to identify students with high SAD tendencies. This study will contribute to the understanding of high school students with high SAD tendencies in Japan.

Greater functional activation during galvanic vestibular stimulation is associated with improved postural stability: a GVS-fMRI study.

PURPOSE: Previous literature has shown that standing stability relies on the vestibular system; however, the neural correlates underlying standing stability remains unclear. This study aimed to investigate the neural correlates of standing stability using functional magnetic resonance imaging (fMRI) following galvanic vestibular stimulation (GVS). MATERIALS AND METHODS: Forty-five healthy right-handed healthy volunteers were included. Postural stability was measured using the modified Clinical Test of Sensory Interaction and Balance (mCTSIB), which measures swaying speed and area on hard and soft surfaces when the volunteer's eyes are open and closed. Functional activation as determined by the blood oxygenation level-dependent (BOLD) response, was measured during GVS using fMRI. We investigated the association between BOLD responses during GVS and postural stability. RESULTS: Relative to rest, participants showed significantly higher BOLD signal during GVS in the parietal operculum, central operculum, and the opercular part of the inferior frontal gyrus. Moreover, functional activation in the central operculum was negatively correlated with standing stability, indexed using swaying speed when volunteers stood on a foam surface with their eyes closed. CONCLUSIONS: Our findings suggest that the neural correlates of standing stability involve greater functional activation in the central operculum.

The Independent Relationship Between Leg Skeletal Muscle Mass Asymmetry and Gait Speed in Community-Dwelling Older Adults.

OBJECTIVES: To investigate the relationship between leg skeletal muscle mass asymmetry and usual gait speed in older adults. METHODS: The subjects were 139 community-dwelling older adults. The asymmetry index was calculated using the leg skeletal muscle mass index (LSMI) values of both legs. The subjects were divided into "large" and "small" asymmetry groups based on the asymmetry index. The relationship between asymmetry and gait speed was analyzed using a linear regression model. The appendicular skeletal muscle mass index and LSMI were included as adjustment variables in the analysis. RESULTS: The asymmetry index and having a "large" asymmetry were independently related to gait speed, even after adjusting for covariates such as appendicular skeletal muscle mass index and LSMI. DISCUSSION: Leg skeletal muscle mass asymmetry was related to gait speed independently of the appendicular skeletal muscle mass index and LSMI values. A skeletal muscle mass evaluation among older adults should include an assessment of the total skeletal muscle mass and its asymmetry.

Standing postural stability during galvanic vestibular stimulation is associated with the motor function of the hemiplegic lower extremity post-stroke.

Background: The vestibular system is profoundly involved in standing postural stability. Patients with post-stroke hemiparesis have poor postural control function; nevertheless, it is unclear as to how the vestibular system affects postural control after stroke.Objectives: The purpose of this study was to quantitatively evaluate the relationship between galvanic whole-body sway responses and motor function of the hemiplegic lower extremity post-stroke.Methods: Thirty stroke patients and 49 healthy controls underwent standing body sway tests to examine postural control function during vestibular stimulation. Postural stabilization was measured using a C7-mounted accelerometer during galvanic vestibular stimulation. Postural stability was assessed during stimulation while quietly standing with eyes closed. For the stroke group, lower extremity function was measured using the Fugl-Meyer Assessment scale (FMA-LE).Results: The standing body sway test scores during stimulation were lower in the stroke group than the control group (p = .010). In the stroke group, correlation analysis demonstrated that the standing body sway response score was significantly associated with the FMA-LE (r = 0.374, p = .021).Conclusions: Motor dysfunction directly causes standing postural instability during vestibular stimulation, even though sensory information suggests normal peripheral vestibular function. Therefore, motor dysfunction of the hemiplegic lower extremity might lead to inhibition of normal standing postural stability.

Effects of a water-based exercise program on disability prevention in older Japanese adults.

AIM: This study aimed to evaluate the potential preventive effects of a water-based exercise program on disability in community-dwelling older adults. METHODS: The study design was a propensity score-matched retrospective study. Older adults were contacted through a mail survey carried out by City Hall, and those who scored ≥3 points on the physical domain of the Kihon Checklist were encouraged to participate in the water-based exercise program. The program consisted of aerobic and walking exercises in the water for 1 h, once a week for 6 months. Propensity scores were used to match individuals who participated in the exercise program with control individuals based on age, sex, height, weight, body mass index and Kihon Checklist score. Among matched pairs, the study included 278 participants (control group 139, intervention group 139). The main outcome was the number of participants who received a new long-term care insurance certification during the first follow-up year, which was used to indicate disability. RESULTS: Of the 278, 13 participants (5.5%) required long-term care insurance certification. A significantly smaller proportion of intervention group members required long-term care insurance certification (intervention group 0.7% [1/139 participants] vs control group 8.6% [12/139 participants], P = 0.003). CONCLUSIONS: Water-based exercise program appears to effectively prevent disability in community-dwelling older adults. Because water-based exercise program is associated with a minimal burden on joints and lower risk of falling, it might particularly enable the prevention of disability in older adults with chronic pain and restricted mobility. Geriatr Gerontol Int 2019; 19: 1282-1288.

The effects of electromyography-triggered neuromuscular electrical stimulation plus tilt sensor functional electrical stimulation training on gait performance in patients with subacute stroke: a randomized controlled pilot trial.

The effects of electromyography-triggered neuromuscular electrical stimulation and tilt sensor functional electrical stimulation on ankle dorsiflexion during walking are unclear. This study investigated whether combined electrical stimulation training affects gait performance in patients with stroke. Thirty-six patients were randomly assigned to a control (n = 13), electromyography-triggered neuromuscular electrical stimulation training (single electrical stimulation group, n = 12), or a combined electromyography-triggered neuromuscular electrical stimulation and tilt sensor functional electrical stimulation training (combined electrical stimulation group, n = 11) group. Both experimental groups undertook 60-minute interventions for two weeks. All patients' gait performances were evaluated according to walking speed and trunk acceleration during 10-meter walking tests undertaken pre-intervention and at two weeks post-intervention. A wireless triaxial accelerometer measured trunk acceleration, and the root mean square values of the vertical, mediolateral, and anterioposterior planes were calculated from randomly selected 10-step sequences. Compared with baseline, the 10-meter walking tests improved significantly after two weeks in the single and combined electrical stimulation groups. In the combined electrical stimulation group, the 10-meter walking tests scores and root mean square of the mediolateral plane improved significantly compared with those in the control group. Electromyography-triggered neuromuscular electrical stimulation and tilt sensor functional electrical stimulation training may improve body perturbation stability and walking quality.

The Emotional Intelligence of Japanese Mental Health Nurses.

The aim of this study was to measure emotional intelligence in nurses in Japan, and to elucidate the characteristics of mental health nurses. Anonymous, self-administered questionnaires were distributed to 206 nurses working in three psychiatric hospitals and two internal medicine hospitals in Japan. The number of participants included in the analysis was 159 (valid response rate, 77.2%), of which 87 were mental health nurses. Emotional intelligence was measured using the Japanese version of the Wong and Law Emotional Intelligence Scale. In the analysis, the emotional intelligence of mental health nurses and internal medicine nurses was compared using a t-test. The results of a t-test comparing emotional intelligence scale scores between the mental health nurses and internal medicine nurses showed that the total mean score and Self-Emotions Appraisal score were significantly lower in mental health nurses than in internal medicine nurses. The self-awareness of mental health nurses was significantly lower than that of nurses in other fields (P < 0.001, Cohen's d: 0.65). The results of this study provide a basis for future research on the emotional intelligence of nurses in Japan. Development of an emotional intelligence scale based on the characteristics of Japanese nurses will be important regarding nurses' assessment of their own emotions and the emotions of others. The kinds of people nurses are involved with and the content of their support for others also need to be clarified.

Effects of the combination therapy of tilt sensor functional electrical stimulation and integrated volitional control electrical stimulation on brain activity during the subacute phase following stroke: a feasibility study.

[Purpose] The aim of this study was to investigate whether the combination of integrated volitional control functional electrical stimulation and tilt sensor functional electrical stimulation training affected brain activation during the subacute phase following a stroke. [Participant and Methods] The patient was a 60-year-old male with right hemiparesis, secondary to stroke in the left thalamus. Conventional intervention was performed for 60 minutes per day during the first two weeks of treatment (the control condition). Functional electrical stimulation intervention, including integrated volitional control functional electrical stimulation and tilt sensor functional electrical stimulation training, was then performed for 60 minutes per day for two weeks (the experimental condition). These sessions were repeated four times. Brain activity was measured during voluntary right ankle dorsiflexion in both sessions, using functional magnetic resonance imaging. Brain activity measurements were obtained a total of eight times every two weeks (34, 48, 62, 76, 90, 104, 118, and 132 days following the stroke). [Results] There was a significantly higher level of activation in the bilateral cerebellum and the left side of the supplementary motor area in the experimental condition than in the control condition. [Conclusion] The present study demonstrates that the combination of integrated volitional control functional.

Transient Effects of Gaze Stability Exercises on Postural Stability in Patients With Posterior Circulation Stroke.

The authors sought to investigate if short-term gaze stability exercises have an effect on postural stability of dynamic standing during neck movement in patients with posterior circulation stroke (PCS). Patients in both PCS and non-PCS groups were assigned to either an intervention or control group. The intervention group performed the gaze stability exercises for 10 min while the control group was merely resting. The center of pressure velocity was calculated to evaluate the postural stability. After intervention, PCS and non-PCS showed a significant reduction in center of pressure velocity during dynamic standing with eyes closed condition, and the PCS group showed a significant improvement in eye-opened condition. This study indicated that gaze stability exercises improve PCS patients' postural control, especially during dynamic standing.

Increased activity in the right prefrontal cortex measured using near-infrared spectroscopy during a flower arrangement task.

OBJECTIVE: Flower arrangement program (FAP) horticultural therapy promotes psychological, social and physiological wellness and recovery. Moreover, FAPs have been used to evaluate the outcomes related to visuospatial working memory; yet, most of these studies used subjective outcome measures such as behavioural observations and questionnaires. Few studies report objective evaluations of FAP effects in humans. In the present study, we measured the effects of an FAP task on frontal lobe activity in healthy participants using near-infrared spectroscopy. We quantified salivary amylase levels as an indicator of stress level during the FAP. METHODS: The FAP task involved a predetermined arrangement pattern of natural materials (flowers and leaves) that required the participants to identify where a given material should be placed and temporarily memorise the designated position to complete the flower arrangement. The FAP task was compared to the block-tapping task (BTT), which is routinely used to evaluate visuospatial working memory. RESULTS: Both the FAP task and BTT positively stimulated the right prefrontal cortex; however, stress was more effectively limited during the performance of the FAP task. CONCLUSIONS: Our data suggest that FAP therapy may be useful for the rehabilitation of patients who are sensitive to stress.

Near-infrared spectroscopy can reveal increases in brain activity related to animal-assisted therapy.

[Purpose] Previous studies have indicated that animal-assisted therapy can promote recovery of psychological, social, and physiological function in mental disorders. This study was designed as a pilot evaluation of the use of near-infrared spectroscopy to objectively identify changes in brain activity that could mediate the effect of animal-assisted therapy. [Subjects and Methods] The participants were 20 healthy students (10 males and 10 females; age 19-21 years) of the Faculty of Agriculture, Saga University. Participants were shown a picture of a Tokara goat or shack (control) while prefrontal cortical oxygenated haemoglobin levels (representing neural activity) were measured by near-infrared spectroscopy. [Results] The prefrontal cortical near-infrared spectroscopy signal was significantly higher during viewing of the animal picture than during a rest condition or during viewing of the control picture. [Conclusion] Our results suggest that near-infrared spectroscopy can be used to objectively identify brain activity changes during human mentation regarding animals; furthermore, these preliminary results suggest the efficacy of animal-assisted therapy could be related to increased activation of the prefrontal cortex.

Poor gait performance is influenced with decreased vestibulo-ocular reflex in poststroke patients.

The vestibulo-ocular reflex (VOR) exerts a significant influence on gait performance. Therefore, a decrease in VOR function could worsen gait impairments in patients with poststroke hemiparesis. The effects of decreased VOR function on gait performance could be further exacerbated by aging-related physical weakness and impaired motor function of the hemiparetic lower limb. The aim of our study was to evaluate the possible synergistic effect of aging and impairment in lower extremity function and the VOR on walking ability of poststroke hemiplegic patients. The VOR was evaluated, using the gaze-stabilization test (GST), in 75 patients with a poststroke hemiplegia. Lower extremity function was assessed using the Fugl-Meyer assessment (FMA-LE). Gait performance was evaluated using the 10-m walking test, the timed up-and-go, and the dynamic gait index (DGI). The relationships between gait performance and age, FMA-LE and GST, as well as whether age, FMA-LE, and/or GST were significant predictors of gait performance were evaluated. The 10-m walking test, timed up-and-go and DGI were significantly correlated to the FMA-LE and GST (P<0.05). On stepwise multiple regression analysis, the GST remained a significant predictor of the DGI (P<0.001). The present study indicates that decreased VOR function after stroke contributes to impairments in gait both in simple and in dual-task walking tests.

Effects of vestibular rehabilitation on gait performance in poststroke patients: a pilot randomized controlled trial.

The effects of vestibular rehabilitation on poststroke patients are unknown. This study aimed to investigate whether or not vestibular rehabilitation would improve both the vestibulo-ocular reflex and gait performance of patients with poststroke hemiparesis. Twenty-eight patients with stroke were assigned randomly to either an experimental group (N=14) or a control group (N=14). The experimental group performed the conventional physical therapy for 40 min and vestibular rehabilitation for 20 min, as a 60 min session, during the first 3 weeks and then completed only the conventional intervention for 60 min for the following 3 weeks. The control group performed only the 60 min conventional physical therapy for 6 weeks. Both groups were measured using the gaze stabilization test, the 10 m walking test, the timed up and go test, and the dynamic gait index. Patients were assessed at baseline, and at 3 and 6 weeks. Although the control group showed no significant difference in any outcome measures, the experimental group showed an improvement in gaze stabilization test scoring, which increased significantly after 3 weeks compared with the baseline (P=0.030). The dynamic gait index was also significantly increased after 3 and 6 weeks compared with the baseline (P=0.049 and 0.024, respectively). This study indicated that vestibular rehabilitation might improve poststroke patients' vestibulo-ocular reflex. Moreover, patients might show improved gait performance at least up to 3 weeks after the vestibular intervention by the sensory reweight to coordinate vestibular input.

Factors influencing executive function by physical activity level among young adults: a near-infrared spectroscopy study.

[Purpose] Prevention of dementia requires early intervention against it. To ensure that early interventions are effective it is crucial to study the cognitive functions related to dementia in young adulthood. Moreover, it is needed not only to verify the cognitive function test but also to elucidate the actual brain activity and the influence of related factors on the brain activity. To investigate the factors influencing cognitive function among young adults and examine the differences in executive function by physical activity level. [Subjects and Methods] Forty healthy university students (mean age, 20.4 years) were classified into two groups by cognitive function score (HIGH and LOW), determined according to Trail Making Test performance and Stroop task processing time. We then assessed what factors were related to cognitive function by logistic regression analysis. Executive function was determined by brain blood flow using near-infrared spectroscopy during the Stroop task, and was then compared by physical activity levels (determined according to number of steps per hour). [Results] Full-scale Intelligence Quotient according to the 3rd Wechsler Adult Intelligent Scale and number of steps per hour influenced cognitive function score, with odds ratios of 1.104 and 1.012, respectively. Oxy-hemoglobin concentrations in areas related to executive function during the Stroop task were significantly higher among those in the high physical activity group than among those in the low physical activity group. [Conclusion] The study revealed that Full-scale Intelligence Quotient and a number of steps per hour are factors associated with the cognitive functions in young adulthood. In addition, activity in execution function related area was found to be significantly higher in the high physical activity group than in the low physical activity group, suggesting the importance of physical activity for enhancing young adulthood cognitive functions.

Relationship between pulmonary function and elevated glycated hemoglobin levels in health checkups: A cross-sectional observational study in Japanese participants.

BACKGROUND: Insulin resistance has been associated with cytokines, including interleukin-6 and tumor necrosis factor alpha soluble receptor, both of which are elevated in chronic obstructive pulmonary disease (COPD). Few studies have investigated the relationship between pulmonary function tests using spirometry (PFT) and fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c) levels in Japanese participants. The purpose of this study was to clarify the relationship between PFT in Japanese people who had health checkups and their FPG or HbA1c levels. In the context of preventative medicine, we intend to connect early detection of COPD to an index of blood sugar. METHODS: From August 2013 through March 2014, 1019 participants underwent health checkups. PFT, FPG, and HbA1c measurements were conducted. HbA1c levels were measured according to National Glycohemoglobin Standardization Program guidelines. RESULTS: Participants with FPG ≥100 mg/dL and HbA1c ≥5.6% showed a significantly lower forced expiratory volume in 1 s:forced vital capacity ratio (FEV1/FVC) compared to participants with lower FPG and Hb1Ac levels. Prevalence of FEV1/FVC values <70% in PFT differed significantly depending on sex, age, body mass index, FPG, HbA1c, and smoking habits. Age (≥60 years), HbA1c (≥5.6%), and current or former smoking were associated with FEV1/FVC values <70%. CONCLUSION: In Japan, HbA1c levels were higher in participants with FEV1/FVC values <70% in PFT than in those with FEV1/FVC ≥70%. In preventive medicine, PFT by spirometry should be performed in elderly participants with elevated HbA1c levels who are current or former smokers.

Greater Cervical Muscle Fat Infiltration Evaluated by Magnetic Resonance Imaging is Associated With Poor Postural Stability in Patients With Cervical Spondylotic Radiculopathy.

STUDY DESIGN: A population-based, cross-sectional study. OBJECTIVE: The aim of this study was to quantitatively evaluate the relationship between static postural stability and fat infiltration within cervical multifidus muscle in patients with cervical spondylotic radiculopathy (CSR). SUMMARY OF BACKGROUND DATA: CSR causes denervation by compression of nerve roots. This denervation is detected by fatty infiltration or results in fatty infiltration within muscles. Proprioceptive information in cervical multifidus muscle plays an important role in coordinated movement of postural stability; however, there have been few studies evaluating the relationship between postural stability and fat infiltration within cervical multifidus muscle among CSR patients. METHODS: Sixteen CSR patients with C6 injuries and 25 age-matched healthy controls underwent magnetic resonance images to examine bilateral cervical multifidus muscle. For evaluation of fat within muscle, a muscle fat index (MFI) was calculated by using both measurement of cervical multifidus muscle and intermuscular fat. Participants' postural stability at upright position with eyes-opened and eyes-closed for 60 seconds was examined by a platform. Two parameters, the total length and the area of the center of pressure (COP), were used for evaluation. RESULTS: The CSR group showed significantly poorer postural stability than the control group (eyes-opened the total length; P < 0.05, eyes-closed the total length; P < 0.05, eyes-closed the area; P < 0.05). There were significant group differences at C4, C5, and C6 MFI (P < 0.05). In the CSR group, a correlation analysis demonstrated that the age, C4, C5, and C6 MFI values were significantly associated with the eyes-closed the total length of the COP (P < 0.05). CONCLUSIONS: Fat infiltration within muscle could lead to inhibition of normal activity of musculature. The present study suggests that fat within cervical multifidus muscle could directly cause postural instability in static standing, even though the proprioceptive information has normal lower limbs.

Effect of neck and trunk rotation speeds on cerebral cortex activity and standing postural stability: a functional near-infrared spectroscopy study.

[Purpose] The aim of the present study was to determine whether different neck and trunk rotation speeds influence standing postural stability or frontal and temporal cortical activity during rotation in healthy young adults. [Subjects and Methods] Twelve healthy volunteers participated in this study. A custom turn-table operated by one of the experimenters was placed on a platform to assess postural perturbation. Subjects were asked to stand barefoot on the turn-table in an upright position with their feet together, and measurements were obtained during high- and low-speed rotations. Postural stability was tested using a force platform and a head sensor. Cerebral cortex activity was measured using functional near-infrared spectroscopy. Brain activity, center of pressure, and head perturbation were measured simultaneously for each subject. [Results] Significant differences were found in the center of pressure and the head angular velocity between high- and low-speed rotations. However, compared to baseline, oxygenated hemoglobin levels were not significantly different during high- or low-speed rotations. [Conclusion] Automatic postural responses to neck and trunk rotation while standing did not significantly activate the cerebral cortex. Therefore, the response to stimuli from the feet may be controlled by the spinal reflex rather than the cerebral cortex.

Effects of exercise on the nephron of Goto-Kakizaki rats: morphological, and advanced glycation end-products and inducible nitric oxide synthase immunohistochemical analyses.

The current study aimed to examine how exercise affects morphology of the nephron, and localization of advanced glycation end-products (AGEs) and inducible nitric oxide synthase (iNOS) immunoreactivity in diabetic Goto-Kakizaki rats. Four groups of male rats were studied. WIS SED (Wistar rats; sedentary) group served as a control. Other groups were WIS EX (Wistar rats; exercise), GK SED (Goto-Kakizaki diabetic rats; sedentary) and GK EX (Goto-Kakizaki diabetic rats; exercise) groups. The rats in EX groups were subjected to 15weeks of treadmill running at a speed of 15m/min for a total of 30minutes, three times a week. Changes in the structure of renal corpuscles and in the distribution of AGEs- and iNOS-immunoreactive cells of the uriniferous tubules were evaluated. Every parameter of GK EX was significantly different from that of GK SED (area of Bowman's capsules: p<0.001, area of glomeruli: p<0.05 and the occupancy of a glomerulus: p<0.05). These findings suggest that exercise may ameliorate glomerular filtration rate (GFR). The localizations of AGEs and iNOS immunostaining in the uriniferous tubules were similar in each group. Immunohistochemical assays revealed that the number of the AGEs and iNOS immunopositive cells of the proximal tubule of cortico-deep layer in EX groups were markedly greater than those in SED groups and that iNOS expression in GK EX was significantly higher than GK SED (p<0.05). Exercise seems to normalize the GFR and glomerular filtrate absorption from the uriniferous tubules in Goto-Kakizaki diabetic rats with the recovered shape of renal corpuscles and may be involved in the absorption and catabolization of AGEs with iNOS-related reactions for reabsorption.