Association of Physical Activity and Sleep Metrics with Depression in People with Type 1 Diabetes

Objective

This study aimed to investigate the association of physical activity and sleep metrics, measured via wrist-worn accelerometers, with depression in people with type 1 diabetes.

Patients and Methods

People with type 1 diabetes were recruited from the Dasman Diabetes Institute in Kuwait and were invited to wear a wrist-worn accelerometer device for 7 days. Mean physical activity (overall acceleration), inactivity, light activity, moderate activity, vigorous activity, the distribution of physical activity intensity (intensity gradient), sleep duration and sleep efficiency were quantified from the accelerometer data. The associations of these metrics with depression were investigated using multiple linear regression.

Results

A total of 551 people with type 1 diabetes (age 33.1 (9.5) years) were included. Overall physical activity (B = -0.09, CI = -0.14 to -0.04), moderate intensity activity (B = -0.02, CI = -0.02 to -0.01), vigorous intensity activity (B = -0.16, CI = -0.27 to -0.05), and the intensity gradient (B = -2.11, CI = -3.51 to -0.72) were negatively associated with depression score (p < 0.01) and these associations remain significant even after adjustment for age, sex, diabetes duration, and BMI. However, sleep duration and efficiency were not associated with depression. After mutual adjustment overall physical activity (B = -0.07, CI = -0.12 to -0.01), but not the intensity gradient (B = -0.90, CI = -2.47 to 0.68), remained associated with depression.

Conclusion

Overall, moderate and vigorous physical activity, and the intensity gradient were associated with lower symptoms of depression. Overall physical activity, rather than the distribution of activity intensity, appears more important in depression. This information can help guide physical activity interventions to improve depression in people with type 1 diabetes.

Independent and joint associations of aerobic and muscle-strengthening exercise with mental health in adolescents: A cross-sectional analysis before and during COVID-19 using the 2015-2021 National Youth Risk Behavior Survey

PURPOSE

COVID-19 led to social isolation that may have compromised adolescent mental health. This study examined the independent and joint associations of aerobic physical activity (PA) and muscle-strengthening exercise (MSE) with mental health problems in adolescents.

METHODS

Participants were US adolescents who completed the 2015-2021 National Youth Risk Behavior Survey (N = 61,298; 45.7% female). Data were collected between 2015 and 2021 and analyzed in 2023. Outcomes were binary response items asking about feeling sad/hopeless, having difficulty concentrating, remembering, or making decisions, and having a suicidal ideation. Preventive exposure variables were items asking about frequencies of aerobic PA and MSE with responses dichotomized to align with recommendations. Independent and joint associations were examined using robust Poisson regression with covariates selected using double selection lasso. Structural equation models examined the associations treating PA and MSE as continuous predictors and poor mental health as a latent dependent variable.

RESULTS

Meeting either recommendation alone associated with a 4-10% lower prevalence of mental health problems (APR = 0.90-0.96, p < 0.05), and meeting both recommendations associated with a 15%-20% lower prevalence of mental health problems (APR = 0.80-0.85, p < 0.001). Although categorical joint associations were stronger in males (p < 0.05), multiplicative interactions were observed in females using continuous variables for PA and MSE (β = -0.09, p < 0.001).

CONCLUSION

Meeting aerobic PA and MSE recommendations associated with lower prevalence of mental health problems. Participation in MSE below recommended levels may be beneficial for females when combined with aerobic PA. Future research should examine these associations by acquiring contextual information and device-based assessments.

The role of exercise in the treatment of depression: biological underpinnings and clinical outcomes

Globally, depression is a leading cause of disability and has remained so for decades. Antidepressant medications have suboptimal outcomes and are too frequently associated with side effects, highlighting the need for alternative treatment options. Although primarily known for its robust physical health benefits, exercise is increasingly recognized for its mental health and antidepressant benefits. Empirical evidence indicates that exercise is effective in treating individuals with depression; however, the mechanisms by which exercise exerts anti-depressant effects are not fully understood. Acute bouts of exercise have been shown to transiently modulate circulating levels of serotonin and norepinephrine, brain-derived neurotrophic factor, and a variety of immuno-inflammatory mechanisms in clinical cohorts with depression. However, exercise training has not been demonstrated to consistently modulate such mechanisms, and evidence linking these putative mechanisms and reductions in depression is lacking. The complexity of the biological underpinnings of depression coupled with the intricate molecular cascade induced by exercise are significant obstacles in the attempt to disentangle exercise's effects on depression. Notwithstanding our limited understanding of these effects, clinical evidence uniformly argues for the use of exercise to treat depression. Regrettably, exercise remains underutilized despite being an accessible, low-cost alternative/adjunctive intervention that can simultaneously reduce depression and improve overall health. To address the gaps in our understanding of the clinical and molecular effects of exercise on depression, we propose a model that leverages systems biology and multidisciplinary team science with a large-scale public health investment. Until the science matches the scale of complexity and burden posed by depression, our ability to advance knowledge and treatment will continue to be plagued by fragmented, irreproducible mechanistic findings and no guidelines for standards of care.

Physical exercise is tied to emotion-related impulsivity: insights from correlational analyses in healthy humans

Seminal work has found a negative association between physical exercise and impulsivity levels in humans. This paper aims to strengthen these findings by evaluating the association between the amount of self-reported physical exercise per week and emotion-related impulsivity whilst considering age and gender as covariates on a large-scale dataset.Participants completed an online self-report questionnaire about emotion-related impulsivity (i.e. Feelings Trigger Action) and exercise-related questions. After quality control, 773 participants were included in the analysis. Correlational analyses and a multiple regression model explaining the emotion-related impulsivity scores via the amount of exercise per week and demographic characteristics (i.e. age and gender) were performed.The number of hours spent exercising per week was significantly inversely correlated with the Feelings Trigger Action score (r = -.131, p < .001) and two out of its three subscales. The multiple linear regression model showed that hours of exercise per week and gender were significantly associated with the Feelings Trigger Action score (std. β = -.122, p < .001), however, this model explained only 3.2% of the overall variance.This large-scale dataset confirms seminal work displaying an inverse association between emotion-related impulsivity and hours of exercise per week. Further studies are required to understand the mechanisms underlying the relationship between the two variables. HighlightsThis study (N = 773) confirms seminal work on the connection between exercise and impulsivity.When controlling for demographic variables, the amount of exercise per week was inversely correlated (small effect size) with emotion-related impulsivity levels.In the multiple-regression model, hours of exercise per week and gender were significantly associated with the Feelings Trigger Action score.

The positive impact of 12 weeks of dance and balance training on the circulating amyloid precursor protein and serotonin concentration as well as physical and cognitive abilities in elderly women

BACKGROUND

The study aimed to compare the effectiveness of 12-weeks dance training with balance training on fall risk, physical and cognitive functions. The study's second aim was to evaluate the association between physical and cognitive functions with circulating markers of neurodegeneration and cognitive impairments in elders.

MATERIALS AND METHODS

30 older women (aged 73.3 ± 4.5) were randomly assigned into three groups: balance training (BG), dance training (DG) and control group (CG). To assess the study aims Time up and go test (TUG), 6 minute walk test (6MWT), determination test (DT), blood amyloid precursor protein (APP) and serotonin concentration were performed.

RESULTS

The results showed an improvement in 6MWT (p = 0.0001 for DG and BD), walking speed (p = 0.0001 for DG and BG) and TUG, only for DG (p = 0.0013). The number of correct responses in DT increased in both groups (p = 0.014 and p = 0.005, for DG and BG, respectively). In DG the increase in the total number of reactions was observed (p = 0.013). The improvement in cognitive and physical functions was associated with an increase in APP (p = 0.036 and p = 0.014) and a decrease in serotonin concentrations (p = 0.042 and p = 0.049), respectively in DG and BG.

CONCLUSION

Dance training intervention could have more benefits on elders' physical and cognitive functions. However, both trainings may be important factors modifying the concentration of circulating proteins associated with neurodegenerative and cognitive disorders.

Symptoms of depression are associated with reduced leisure-time physical activity in adult individuals with type 1 diabetes

AIMS

Here, we investigated the association between depressive symptoms and leisure-time physical activity (LTPA) in type 1 diabetes.

METHODS

Data from adult individuals with type 1 diabetes without evidence of diabetic kidney disease or macrovascular complications, participating in the Finnish Diabetic Nephropathy Study, were included. Based on a questionnaire, weekly LTPA as metabolic equivalent of task hour was calculated. Activity levels (inactive, moderately active, active), weekly frequencies (< 1, 1-2, > 2), intensities (low, moderate, high), and single session durations (< 30, 31-60, > 60 min) were assessed. Depressive symptomatology was evaluated using the Beck Depression Inventory (BDI). We calculated a continuous BDI score and divided participants into those with (BDI score ≥ 16) and without (BDI score < 16) symptoms of depression. For sensitivity analyses, we additionally defined symptoms of depression with antidepressant agent purchases within a year from the study visit.

RESULTS

Of the 1339 participants (41.7% men, median age 41 years), 150 (11.2%) reported symptoms of depression. After adjustments, both higher BDI scores and depressive symptomatology were associated with more inactive lifestyle, and lower frequency and intensity of the LTPA. The BDI score was additionally associated with shorter single session duration. For antidepressant purchases, lower odds were observed in those with higher intensity and longer single session duration of LTPA.

CONCLUSIONS

Depressive mood is harmfully related to LTPA in type 1 diabetes. In order to improve the long-term health of individuals with type 1 diabetes, efforts to increase both mental well-being and physical activity should be taken.

Risk Factors for Depressive Symptoms in Korean Adult Stroke Survivors: The Korea National Health and Nutrition Examination Survey IV-VII (2007-2018)

Depressive symptoms are common in stroke survivors, and they are associated with poor outcomes. Therefore, this study aimed to investigate the depressive symptoms in stroke survivors and the risk factors for depressive symptoms in stroke survivors. We included 33,991 participants who were 19 years or older and had completed a questionnaire about the history of stroke from the Korea National Health and Nutrition Examination Survey (KNHANES) IV–VII (from 2007 to 2018). The mean Patient Health Questionnaire-9 score and the prevalence of major depression, depressive symptoms, antidepressant treatment, suicidal ideation, and suicide attempts were significantly higher in stroke survivors than in non-stroke participants (4.4 vs. 2.6, 16.2% vs. 5.3%, 24.7% vs. 9.3%, 3.8% vs. 1.4%, 21.7% vs. 4.8%, and 2.5% vs. 0.6%, respectively, all p < 0.001). Complex sample multivariate logistic regression analysis revealed that the female sex, unemployment, a low education level, a low family income, and activity limitations were independent risk factors for depressive symptoms in stroke survivors. Activity limitations showed the highest odds ratio among the independent factors, and its causes were further analyzed. The most common causes of activity limitations were stroke sequelae and musculoskeletal problems. To reduce depressive symptoms in stroke survivors, attention needs to be paid to minimizing stroke sequelae and musculoskeletal problems along with regular screening for depressive symptoms.

Quantification of Plasma Kynurenine Metabolites Following One Bout of Sprint Interval Exercise

The kynurenine pathway of tryptophan degradation produces several neuroactive metabolites suggested to be involved in a wide variety of diseases and disorders, however, technical challenges in reliably detecting these metabolites hampers cross-comparisons. The main objective of this study was to develop an accurate, robust and precise bioanalytical method for simultaneous quantification of ten plasma kynurenine metabolites. As a secondary aim, we applied this method on blood samples taken from healthy subjects conducting 1 session of sprint interval exercise (SIE). It is well accepted that physical exercise is associated with health benefits and reduces risks of psychiatric illness, diabetes, cancer and cardiovascular disease, but also influences the peripheral and central concentrations of kynurenines. In line with this, we found that in healthy old adults (n = 10; mean age 64 years), levels of kynurenine increased 1 hour (P = .03) after SIE, while kynurenic acid (KYNA) concentrations were elevated after 24 hours (P = .02). In contrast, no significant changes after exercise were seen in young adults (n = 10; mean age 24 years). In conclusion, the described method performs well in reliably detecting all the analyzed metabolites in plasma samples. Furthermore, we also detected an age-dependent effect on the degree by which a single intense training session affects kynurenine metabolite levels.

Effect of Gender, Physical Activity and Stress-Related Hormones on Adolescent's Academic Achievements

BACKGROUND

Physical activity (PA) has been shown to develop better fitness and body function in children. Various studies have shown that as the age of students increases, its correlation with school achievement decreases. Different hormonal changes during adolescence make it difficult to adjust in his/her environment, causing stress. To the best of our knowledge, no study has studied the correlation between stress-related hormones and school performance among adolescents. This study was conducted to evaluate physical activity and stress-related hormones, cortisol and serotonin, among school adolescents aged 12-18 years old and find their association with academic achievements.

METHODS

A total of 300 students were invited to participate in this study. Physical activity of the participants was assessed in relation to the time spent performing various physical activities. End of the academic year grades were obtained from the school as a collective measure of academic achievement and executive function. The levels of cortisol and serotonin were measured using the competitive immunoassay techniques.

RESULTS

There was a significant correlation between age, gender, BMI, cortisol, serotonin, physical activity score; and academic achievement, and executive functioning among participants. Academic achievement and executive functioning scores correlated positively with gender, serotonin, physical activity score, but negatively with age, BMI and salivary cortisol. Stepwise regression analysis showed that physical activity and demographic parameters and stress-related hormones, cortisol and serotonin, explained around 61.9-77.9% of academic performance and executive functioning variation in school adolescents, especially females.

CONCLUSIONS

Optimal physical activity and release of stress-related hormones could be the determining factor for performance in school and other activities. These results should be taken into consideration while planning the school curriculum.

Effects of military training on plasma amino acid concentrations and their associations with overreaching

IMPACT STATEMENT

The diagnosis of overtraining syndrome and overreaching poses a great challenge. Military training aims at improving the physical performance of the conscripts, but an excessive training load could also lead to overreaching. This study of Finnish conscripts provides new insights into the pathophysiology of overreaching and overtraining through amino acids concentrations. In addition to confirming the possible use of plasma glutamine/glutamate concentration to indicate and predict overreaching, we made a novel finding, i.e. low alanine and arginine concentrations might have a role in performance decrement and fatigue related to overreaching. Moreover, this study is the first to show the possible association between amino acids with putative neuronal properties and overreaching. Thus, the present findings might help to detect and prevent overreaching and offer a reliable diagnostic approach. In order to avoid overreaching, military training should be planned more periodically and individually, especially during the first four weeks of military service.

Physical Literacy, Physical Activity and Health: Toward an Evidence-Informed Conceptual Model

Physical literacy (PL) provides a powerful lens for examining movement in relation to physical activity (PA) and motor skill outcomes, environmental context, and broader social and affective learning processes. To date, limited consideration has been given to the role PL plays in promoting positive health behaviours. There is no clear conceptual framework based on existing empirical evidence that links PL to health, nor has an evidence-informed case been made for such a position. The purpose of this paper is to (1) present a conceptual model positioning PL as a health determinant, and (2) present evidence in support of PL as a health determinant, drawing on research largely from outside physical education. Viewing PL from the perspective of a multidimensional, experiential convergence process enables it to be differentiated from other models. However, parallels between our model and existing models that focus on movement competence are also drawn. Arguing from a pragmatic perspective on PL, we present evidence for positioning PL as a determinant of health from two literature sources: research on motor coordination disorders in children, and associations between motor competence, PA and health in typically developing children. Statistical modelling approaches consistent with the concept of PL are discussed. Results from these approaches-confirmatory factor analysis and cluster analysis-support the idea that measures related to motor competence, motivation and positive affect work in an integrative manner to produce differences in PA and subsequent health outcomes in children. There is increasing interest in PL, particularly in the field of public health. Presenting a model that explicitly links PL to health can lead to the generation of new research questions and the possibility of broadening impact beyond the context of physical education alone. To date, there has been little conceptual attention to what positioning PL as a determinant of health means. By providing an evidence-based model of PL as a determinant of health, we hope to further the discussion and stimulate increased empirical research in the field.

Physical Inactivity Is Associated With Increased Levels of Anxiety, Depression, and Stress in Brazilians During the COVID-19 Pandemic: A Cross-Sectional Study

Objective: To evaluate the levels of anxiety, depression, and stress associated with the practice of physical exercise (PE) during pandemic by COVID-19. Methods: This study has a cross-sectional characteristic and was carried out between May 12 and 14, 2020. An online questionnaire was applied with questions to assess sociodemographic characteristics and physical exercise during the CoVID-19 pandemic, in addition to depression, anxiety, and stress analysis. The study was approved by the local ethics committee (CAAE: 31521720.8.0000.5082). Results: One thousand one hundred and fifty four answered the questionnaire (69.84% female). During the isolation period, the number of participants who declared not to exercise was 54.16%. Women generaly presented higher levels of anxiety, depression, and stress when compared to men (p < 0.0001 for all domains). The risk of having increased anxiety were 118% higher (OR = 2.183; 95% CI = 1.717-2.775), the risk of depression was 152% higher (OR = 2.525; 95% CI = 1.991-3.205), and the risk of stress symptoms increased 75.1% (OR = 1.751; 95% CI = 1.386-2.213) in the participants who did not perform PE when compared to those who maintain regular PE. Conclusion: People who was not involved with PE during the COVID-19 pandemic had higher anxiety, depression, and stress scores. Based on this, it seems important to advise people to continue PE, following all the recommendations of preventive measures of the pertinent health organizations.

Differential impact of endurance, strength, or combined training on quality of life and plasma serotonin in healthy older women

Aging is associated with a progressive decline in physical and neurophysiological functions, and some studies suggest that cerebral serotonin is decreased in older adults. These factors contribute to reduced ability to perform daily activities, influencing quality of life (QoL). Regular physical activity has demonstrated important benefits in reversing ageing effects; however, little is known whether different training protocols might induce differential effects on QoL. The aim of this study was to verify the effects of different types of training on QoL and its relation with plasma serotonin in healthy older women. Forty-eight older women were randomly assigned in four groups: Strength Training (ST), Endurance Training (ET), Combined Training (CT), and Control Group (CG) which was instructed not to engage in any physical exercise during the study time. Participants underwent 12 weeks of training twice a week. Plasma serotonin and a scoring system questionnaire SF-36 for evaluation of QoL were assessed at baseline and after the completion of training protocols. When comparing pre- and post-training periods all trained groups showed improvement in QoL, but the CT improved more domains. Plasma serotonin was significantly lower in the ST and in the CT groups in comparison with controls after the 12-week training. Significant correlations of plasma serotonin with physical functioning, role-physical, general health, vitality, and mental health were observed. CT resulted in higher amelioration in QoL, in comparison with ET or ST only. All training protocols induced significant reductions in peripheral serotonin levels, which were negatively correlated with improvements in QoL.

Poor Diet, Stress, and Inactivity Converge to Form a "Perfect Storm" That Drives Alzheimer's Disease Pathogenesis

North American incidence of Alzheimer's disease (AD) is expected to more than double over the coming generation. Although genetic factors surrounding the production and clearance of amyloid-β and phosphorylated tau proteins are known to be responsible for a subset of early-onset AD cases, they do not explain the pathogenesis of the far more prevalent sporadic late-onset variant of the disease. It is thus likely that lifestyle and environmental factors contribute to neurodegenerative processes implicated in the pathogenesis of AD. Herein, we review evidence that (1) excess sucrose consumption induces AD-associated liver pathologies and brain insulin resistance, (2) chronic stress overdrives activity of locus coeruleus neurons, leading to loss of function (a common event in neurodegeneration), (3) high-sugar diets and stress promote the loss of neuroprotective sex hormones in men and women, and (4) Western dietary trends set the stage for a lithium-deficient state. We propose that these factors may intersect as part of a "perfect storm" to contribute to the widespread prevalence of neurodegeneration and AD. In addition, we put forth the argument that exercise and supplementation with trace lithium can counteract many of the deleterious consequences associated with excessive caloric intake and perpetual stress. We conclude that lifestyle and environmental factors likely contribute to AD pathogenesis and that simple lifestyle and dietary changes can help counteract their effects.

Nonpharmacological Modulation of Chronic Inflammation in Parkinson's Disease: Role of Diet Interventions

Neuroinflammation is increasingly recognized as an important pathophysiological feature of neurodegenerative diseases such as Parkinson's disease (PD). Recent evidence suggests that neuroinflammation in PD might originate in the intestine and the bidirectional communication between the central and enteric nervous system, the so-called "gut-brain axis," has received growing attention due to its contribution to the pathogenesis of neurological disorders. Diet targets mediators of inflammation with various mechanisms and combined with dopaminergic treatment can exert various beneficial effects in PD. Food-based therapies may favorably modulate gut microbiota composition and enhance the intestinal epithelial integrity or decrease the proinflammatory response by direct effects on immune cells. Diets rich in pre- and probiotics, polyunsaturated fatty acids, phenols including flavonoids, and vitamins, such as the Mediterranean diet or a plant-based diet, may attenuate chronic inflammation and positively influence PD symptoms and even progression of the disease. Dietary strategies should be encouraged in the context of a healthy lifestyle with physical activity, which also has neuroimmune-modifying properties. Thus, diet adaptation appears to be an effective additive, nonpharmacological therapeutic strategy that can attenuate the chronic inflammation implicated in PD, potentially slow down degeneration, and thereby modify the course of the disease. PD patients should be highly encouraged to adopt corresponding lifestyle modifications, in order to improve not only PD symptoms, but also general quality of life. Future research should focus on planning larger clinical trials with dietary interventions in PD in order to obtain hard evidence for the hypothesized beneficial effects.

Effects of increased daily physical activity on mental health and depression biomarkers in postmenopausal women

[Purpose] Little is known about the effectiveness of daily physical activity on depression biomarkers in older adults. This study aimed to investigate the effects of increased daily physical activity for 8 weeks on depression biomarkers in postmenopausal women. [Participants and Methods] Thirty-eight postmenopausal females were randomly assigned into a control or an active group and were asked to wear a uniaxial accelerometer for 8 weeks. Blood samples were obtained at baseline and at the end of the intervention. During the intervention, the active group was asked to increase their physical activity level above their usual lifestyle whereas those in the control group maintained their daily lifestyle. [Results] After the 8-week intervention, the step counts of the participants in the active group increased. The serum concentration of the brain-derived neurotrophic factor and serotonin increased significantly in the active group, but not in the control group, as compared with baseline values. The serum concentration of derivatives of reactive oxygen metabolites and biological antioxidant potential did not change after the intervention in either group. [Conclusion] These findings may suggest that promotion of daily physical activity in postmenopausal women has a positive impact on depression without any change in oxidative stress.

Development and validation of exercise rehabilitation program for cognitive function and activity of daily living improvement in mild dementia elderly

We investigated the effect of exercise rehabilitation based on fine motor movement for the elderly with mild dementia. Using electroencephalogram (EEG), the change of brain wave of them based on fine motor movement and comparing the improvement level of cognitive ability and performance capability in daily living activity was recorded. The subjects were the elderly with mild dementia living in a sanatorium in Incheon city. Mini-Mental Status Examination, activity of daily living (ADL), and the influence on depression were examined. After 8-week exercise program, significant difference in cognitive function and ADL was observed, however, and there was no significant difference in depression. In the EEG, there was a significant difference in α-wave. This study suggests the chance to remind the necessity of exercise programs for improving cognitive function and ADL of the elderly with dementia.

Physical activity and suicidal ideation: A systematic review and meta-analysis

BACKGROUND

A potential approach to suicide prevention that has not been closely examined, but which holds promise in terms of widespread dissemination without major side-effects, is physical activity (PA). This systematic review and meta-analysis set out to: (a) explore associations between PA and suicidal ideation (SI) levels, and (b) investigate the effect of PA interventions on SI.

METHODS

Major electronic databases were searched from inception up to 05/2017 to identify quantitative studies reporting an association between PA and SI. A quantitative correlates synthesis and random effects meta-analysis were conducted.

RESULTS

Fourteen of 21 studies in adults (67%) (n = 130,737), 7/14 (50%) in adolescents (n = 539,170) and 2/3 (67%) in older adults (n = 50,745) found a significant negative association between PA- and SI-levels. Pooled adjusted meta-analysis of 14 effect sizes over eight studies and 80,856 people found that those who were "active" versus those who were "inactive" were less likely to have SI (OR = 0.87, 95%CI = 0.76-0.98). Additionally, meeting PA guidelines conferred a significant protective effect against SI (OR = 0.91, 95%CI = 0.51-0.99, P = 0.03; N studies = 3, n people = 122,395), while not meeting guidelines was associated with increased SI (OR = 1.16, 95%CI = 1.09-1.24, P < 0.001; N = 4, n = 78,860). Data from the intervention studies (N = 3, n = 121) was mixed and limited.

LIMITATIONS

Our findings are based mainly on cross-sectional studies, while the majority of studies did not include a rigorous physical activity assessment.

CONCLUSIONS

The current study suggests that higher PA levels are associated with lower SI. However, the associations observed need to be confirmed in prospective observational studies and controlled trials.

Exercise Reduces Lung Fibrosis Involving Serotonin/Akt Signaling

PURPOSE

Idiopathic pulmonary fibrosis (IPF) is a chronic fibrosing interstitial pneumonia, which involves aberrant serotonin (5-hydroxytryptamine [5-HT]) and Akt signaling. As protective effects of chronic aerobic training (AT) have been demonstrated in the context of lung injury, this study investigated whether AT attenuates bleomycin-induced lung fibrosis partly via a reduction of 5-HT and AKT signaling.

METHODS

Seventy-two C57BL/6 male mice were distributed in Control (Co), Exercise (Ex), Fibrosis (Fi), and Fibrosis + Exercise (Fi + Ex) groups. Bleomycin (1.5 UI·kg) was administered on day 1 and treadmill AT began on day 15 and continued for 60 min·d, 5 d·wk for 4 wk. We evaluated total and differential cell counts in bronchoalveolar lavage (BAL), interleukin (IL)-1β, IL-6, CXCL1/KC, IL-10, tumor necrosis factor α, and transforming growth factor β levels in BAL, collagen content in lung parenchyma, 5-HT levels in BAL fluid and in serum, the expression of 5-HT2B receptor, and Akt phosphorylation in lung tissue.

RESULTS

AT reduced bleomycin-increased number of total cells (P < 0.001), neutrophils (P < 0.01), macrophages (P < 0.01), and lymphocytes (P < 0.05) in BAL. It also reduced the levels of IL-1β (P < 0.01), IL-6 (P < 0.05), CXCL1/KC (P < 0.001), tumor necrosis factor α (P < 0.001), and transforming growth factor β (P < 0.001). It increased expression of ant-inflammatory cytokine IL-10 (P < 0.001). It reduced bleomycin-increased 5-HT levels in BAL (P < 0.001) and in serum (P < 0.05). Reductions in collagen fiber deposition (P < 0.01), 5-HT2B receptor expression (P < 0.01), and Akt phosphorylation in lung tissue were observed.

CONCLUSIONS

AT accelerates the resolution of lung inflammation and fibrosis in a model of bleomycin-induced lung fibrosis partly via attenuation of 5-HT/Akt signaling.

Exercise and mental health

There is a growing body of literature that recognizes the positive effects of exercise on mood states such as anxiety, stress and depression, through physiological and biochemical mechanisms, including endorphins, mitochondria, mammalian target of rapamycin, neurotransmitters and the hypothalamic-pituitary-adrenal axis, and via the thermogenic hypothesis. In addition, psychological mechanisms influence the effects of exercise on mood states, as suggested by both the distraction hypothesis and the self-efficacy hypothesis. Exercise has also been shown to reduce inflammation via several different processes (inflammation, cytokines, toll-like receptors, adipose tissue and via the vagal tone), which can contribute to better health outcomes in people suffering from mood disorders.

Effects of programmed exercise on depressive symptoms in midlife and older women: A meta-analysis of randomized controlled trials

OBJECTIVE

To perform a systematic review and meta-analysis to clarify the effect of programmed exercise on depressive symptoms (DSs) in midlife and older women.

METHODS

We carried out a structured search of PubMed-Medline, Web of Science, Scopus, Embase, Cochrane Library and Scielo, from database inception through June 29, 2017, without language restriction. The search included the following terms: "depression", "depressive symptoms", "exercise", "physical activity", "menopause", and "randomized controlled trial" (RCTs) in midlife and older women. The US, UK and Australian Clinical Trials databases were also searched. We assessed randomized controlled trials (RCTs) that compared the effect of exercise for at least 6 weeks versus no intervention on DSs as the outcome (as defined by trial authors). Exercise was classified according to duration as "mid-term exercise intervention" (MTEI; lasting for 12 weeks to 4 months), and "long-term exercise intervention" (LTEI; lasting for 6-12 months). Mean changes (±standard deviations) in DSs, as assessed with different questionnaires, were extracted to calculate Hedges' g and then used as the effect size for meta-analysis. Standardized mean differences (SMDs) of DSs after intervention were pooled using a random-effects model.

RESULTS

Eleven publications were included for analysis related to 1943 midlife and older women (age range 44-55 years minimum to 65.5±4.0 maximum), none of whom was using a hormone therapy. Seven MTEIs were associated with a significant reduction in DSs (SMD=-0.44; 95% CI -0.69, -0.18; p=0.0008) compared with controls. The reduction in DSs was also significant in six LTEIs (SMD=- 0.29; 95% CI -0.49; -0.09; p=0.005). Heterogeneity of effects among studies was moderate to high. Less perceived stress and insomnia (after exercise) were also found as secondary outcomes.

CONCLUSION

Exercise of low to moderate intensity reduces depressive symptoms in midlife and older women.

Monoamines and cortisol as potential mediators of the relationship between exercise and depressive symptoms

A randomized controlled trial was conducted to assess the effects of exercise plus pharmacotherapy on monoamine neurotransmitters (dopamine, noradrenaline, adrenaline, serotonin) and cortisol levels. A total of 26 women with clinical depression were randomly assigned to one of the two groups: aerobic exercise plus pharmacotherapy or only pharmacotherapy. The exercise program consisted of aerobic exercise, 45-50 min/session, three times/week, for 16 weeks. The biological parameters were measured before and after the exercise program. Adding exercise to pharmacotherapy had no additional effects on monoamines and cortisol plasma levels. These data are preliminary outcomes from a small sample and should be replicated.

Differential Gambling Motivations and Recreational Activity Preferences Among Casino Gamblers

This study investigated three different types of gamblers (recreational, problem, and pathological gamblers) to determine differences in gambling motivations and recreational activity preferences among casino gamblers. We collected data from 600 gamblers recruited in an actual gambling environment inside a major casino in South Korea. Findings indicate that motivational factors of escape, sightseeing, and winning were significantly different among these three types of gamblers. When looking at motivations to visit the casino, pathological gamblers were more likely to be motivated by winning, whereas recreational gamblers were more likely to be motivated by scenery and culture in the surrounding casino area. Meanwhile, the problem gamblers fell between these two groups, indicating higher preferences for non-gambling activities than the pathological gamblers. As this study builds upon a foundational previous study by Lee et al. (Psychiatry Investig 6(3):141-149, 2009), the results of this new study were compared with those of the previous study to see if new developments within a resort-style casino contribute to changes in motivations and recreational activity preferences.

Physical activity and exercise attenuate neuroinflammation in neurological diseases

Major depressive disorder (MDD), schizophrenia (SCH), Alzheimer's disease (AD), and Parkinson's disease (PD) are devastating neurological disorders, which increasingly contribute to global morbidity and mortality. Although the pathogenic mechanisms of these conditions are quite diverse, chronic neuroinflammation is one underlying feature shared by all these diseases. Even though the specific root causes of these diseases remain to be identified, evidence indicates that the observed neuroinflammation is initiated by unique pathological features associated with each specific disease. If the initial acute inflammation is not resolved, a chronic neuroinflammatory state develops and ultimately contributes to disease progression. Chronic neuroinflammation is characterized by adverse and non-specific activation of glial cells, which can lead to collateral damage of nearby neurons and other glia. This misdirected neuroinflammatory response is hypothesized to contribute to neuropathology in MDD, SCH, AD, and PD. Physical activity (PA), which is critical for maintenance of whole body and brain health, may also beneficially modify neuroimmune responses. Since PA has neuroimmune-modifying properties, and the common underlying feature of MDD, SCH, AD, and PD is chronic neuroinflammation, we hypothesize that PA could minimize brain diseases by modifying glia-mediated neuroinflammation. This review highlights current evidence supporting the disease-altering potential of PA and exercise through modifications of neuroimmune responses, specifically in MDD, SCH, AD and PD.

Intensity of anxiety is modified via complex integrative stress circuitries

Escalation of anxious behavior while environmentally and socially relevant contextual events amplify the intensity of emotional response produces a testable gradient of anxiety shaped by integrative circuitries. Apprehension of the Stress-Alternatives Model apparatus (SAM) oval open field (OF) is measured by the active latency to escape, and is delayed by unfamiliarity with the passageway. Familiar OF escape is the least anxious behavior along the continuum, which can be reduced by anxiolytics such as icv neuropeptide S (NPS). Social aggression increases anxiousness in the SAM, reducing the number of mice willing to escape by 50%. The apprehension accompanying escape during social aggression is diminished by anxiolytics, such as exercise and corticotropin releasing-factor receptor 1 (CRF1) antagonism, but exacerbated by anxiogenic treatment, like antagonism of α2-adrenoreceptors. What is more, the anxiolytic CRF1 and anxiogenic α2-adrenoreceptor antagonists also modify behavioral phenotypes, with CRF1 antagonism allowing escape by previously submissive animals, and α2-adrenoreceptor antagonism hindering escape in mice that previously engaged in it. Gene expression of NPS and brain-derived neurotrophic factor (BDNF) in the central amygdala (CeA), as well as corticosterone secretion, increased concomitantly with the escalating anxious content of the mouse-specific anxiety continuum. The general trend of CeA NPS and BDNF expression suggested that NPS production was promoted by increasing anxiousness, and that BDNF synthesis was associated with learning about ever-more anxious conditions. The intensity gradient for anxious behavior resulting from varying contextual conditions may yield an improved conceptualization of the complexity of mechanisms producing the natural continuum of human anxious conditions, and potential therapies that arise therefrom.

Exercise Regulation of Cognitive Function and Neuroplasticity in the Healthy and Diseased Brain

Regular exercise broadly enhances physical and mental health throughout the lifespan. Animal models have provided us with the tools to gain a better understanding of the underlying biochemical, physiological, and morphological mechanisms through which exercise exerts its beneficial cognitive effects. One brain region in particular, the hippocampus, is especially responsive to exercise. It is critically involved in learning and memory and is one of two regions in the mammalian brain that continues to generate new neurons throughout life. Exercise prevents the decline of the hippocampus from aging and ameliorates many neurodegenerative diseases, in part by increasing adult hippocampal neurogenesis but also by activating a multitude of molecular mechanisms that promote brain health. In this chapter, we first describe some rodent models used to study effects of exercise on the brain. Then we review the rodent work focusing on the mechanisms behind which exercise improves cognition and brain health in both the normal and the diseased brain, with emphasis on the hippocampus.