Brain-Periphery Interactions in Huntington's Disease: Mediators and Lifestyle Interventions.

Prominent pathological features of Huntington's disease (HD) are aggregations of mutated Huntingtin protein (mHtt) in the brain and neurodegeneration, which causes characteristic motor (such as chorea and dystonia) and non-motor symptoms. However, the numerous systemic and peripheral deficits in HD have gained increasing attention recently, since those factors likely modulate disease progression, including brain pathology. While whole-body metabolic abnormalities and organ-specific pathologies in HD have been relatively well described, the potential mediators of compromised inter-organ communication in HD have been insufficiently characterized. Therefore, we applied an exploratory literature search to identify such mediators. Unsurprisingly, dysregulation of inflammatory factors, circulating mHtt, and many other messenger molecules (hormones, lipids, RNAs) were found that suggest impaired inter-organ communication, including of the gut-brain and muscle-brain axis. Based on these findings, we aimed to assess the risks and potentials of lifestyle interventions that are thought to improve communication across these axes: dietary strategies and exercise. We conclude that appropriate lifestyle interventions have great potential to reduce symptoms and potentially modify disease progression (possibly via improving inter-organ signaling) in HD. However, impaired systemic metabolism and peripheral symptoms warrant particular care in the design of dietary and exercise programs for people with HD.

Hypoxia Sensing and Responses in Parkinson's Disease.

Parkinson's disease (PD) is associated with various deficits in sensing and responding to reductions in oxygen availability (hypoxia). Here we summarize the evidence pointing to a central role of hypoxia in PD, discuss the relation of hypoxia and oxygen dependence with pathological hallmarks of PD, including mitochondrial dysfunction, dopaminergic vulnerability, and alpha-synuclein-related pathology, and highlight the link with cellular and systemic oxygen sensing. We describe cases suggesting that hypoxia may trigger Parkinsonian symptoms but also emphasize that the endogenous systems that protect from hypoxia can be harnessed to protect from PD. Finally, we provide examples of preclinical and clinical research substantiating this potential.

A study on acute expectation effects on affective state and intention after a brief full-body workout in a student sample.

Brief exercise bouts can have positive effects on the affective state, which in turn could affect the intention for future exercise. Such benefits may be enhanced by manipulating expectations. The aim of this study was to examine whether the affective state after physical activity or the intention for future exercise can be influenced by manipulating expectations. Furthermore, the relationship between affect and intention was investigated. In an online experiment, 121 persons completed either a 10-minute workout (PA), a workout after manipulation of expectations (PA + EM), or a control intervention (CG) after randomized group allocation. Data on affective state, expectations, and intention were collected before and after the intervention using questionnaires. After intervention, PA groups showed significantly more positive values than CG in several affective parameters, in other affective parameters, only PA + EM differed from CG. Affect was positively associated with intention alongside outcome expectations. No difference was found in intention. Although no significant effects of expectation manipulation on affective state or intention were found, latent effects cannot be ruled out. Further exploration of the importance of word choice in describing physical activity in the context of interventions to increase physical activity is necessary. Here, affect should be considered.

Validity, reliability, and invariance across sex of a German version of the Behavioral Regulation in Exercise Questionnaire.

Objective: Since there is no scientifically validated German version of the Behavioral Regulation in Exercise Questionnaire (BREQ-3), the aim of this study was to assess its psychometric parameters and invariance across sex in a sample of German-speaking young adults. The BREQ-3 is an instrument measuring the social and internal influences of motivation toward exercising. This tool is widespread within the scientific community and has been validated in several languages. Methods: A total of 271 participants (45% women; mean age = 20.67 ± 2.17 years; effect size ≥ 0.5) filled in the BREQ-3 at one time point, with a small sub-sample (n = 37) responding it a second time after 15 days. Confirmatory Factorial Analysis, Structural Modeling, and Intraclass Correlation Coefficient were used to examine the German version of the questionnaire. Results: Results highlighted a good fit of the six-dimensional model after the removal of two items (CFI = 0.912; SRMR = 0.0594; RMSEA = 0.064), as well as full invariance across sex (pχ2 = 0.218; ΔCFI < 0.01). Internal consistency and reliability were moderate to good. Conclusions: The 22-item German BREQ-3 is a scientifically valid instrument that can be used in cross-national studies dealing with social aspects of exercise behaviors.

Examining acute environmental effects on affective state, expectancy, and intention in sport climbing.

Introduction: Psychological research has shown that, among other variables, affective state, expectancy, and behavioral intention influence whether or not a (physically active) behavior is performed. Environmental effects during physical activity on affective state have been well studied; however, research regarding environmental effects on expectancy or intention is limited. Sport climbing is a form of physical activity that is performed both indoors and outdoors and is therefore considered as suitable to study environmental effects. Therefore, the aim of the present study was to investigate environmental effects during sport climbing on affective state, expectancy, and intention. The nature of the relationship between some of these parameters should also be explored. Methods: Using a within-subjects design, 48 participants were to climb both once indoors in a climbing gym and once outdoors at a crag. The design included questionnaire-based surveys at multiple time points. Affective state, expectancy, and behavioral intention were measured at different test time points. Results: Two-factor repeated-measures ANOVAs revealed significant main effects of the factors environment (indoor - outdoor) and time (T1 - T2 - T3) for affective state, indicating more positive affective state during outdoor climbing. No environment*time interactions were found. Furthermore, significantly higher intention (d = 0.32; p = 0.032) was measured after the outdoor condition (M = 32.5, SD = 4.1) compared to the indoor condition (M = 31.2, SD = 4.7). Multiple linear regressions revealed that expectancies (measured before and after the session) significantly predicted post-climbing intention only indoors. Conclusion: The results at least partly suggest environmental effects on behaviorally relevant variables during climbing. Outdoor climbing might provide more favorable characteristics for physically active behavior compared to indoor climbing. Health psychologists or public health professionals who focus on increasing physical activity for their clients could recommend outdoor climbing over indoor climbing.