Regular Exercise and Depressive Symptoms in Korean Older Adults

The improvement effect of exercise on rats with chronic stress-induced depression-like behavior: a discussion based on the kynurenine pathway

OBJECTIVE

To observe the effects of 4 weeks of voluntary wheel running on depressive-like behavior in a rat chronic stress-induced depression model to explore the anti-depressive mechanism of exercise.

METHODS

In this observational study, 36 Sprague-Dawley rats were randomly divided into control, stress model, and stress exercise groups (12 rats/group). The control group received no intervention, and the stress model and stress exercise group rats underwent chronic mild unpredictable stress and isolation. The stress exercise group rats also underwent 4 weeks of voluntary wheel running. Behavioral changes and hippocampal protein and mRNA expression levels were detected.

RESULTS

Voluntary wheel running significantly increased horizontal and vertical movements, sucrose intake, and the sucrose preference percentage and reduced immobility time in the forced swimming test in depression model rats. The hippocampal tumor necrosis factor-α, interleukin (IL)-6, IL-1β, and quinolinic acid levels were significantly decreased, while the IL-4, IL-10, and kynurenic acid levels were significantly increased. Kynurenine-3-monooxygenase and 3-hydroxyanthranilate-3, 4-dioxygenase mRNA levels were downregulated, and kynurenine aminotransferase mRNA was upregulated.

CONCLUSION

Voluntary wheel running improved depressive-like behavior in depression model rats. The mechanism may be related to a kynurenine pathway metabolite level imbalance, which has neurotoxic and neuroprotective effects, caused by long-term voluntary wheel running.

Late-life depression: Epidemiology, phenotype, pathogenesis and treatment before and during the COVID-19 pandemic

Late-life depression (LLD) is one of the most common mental disorders among the older adults. Population aging, social stress, and the COVID-19 pandemic have significantly affected the emotional health of older adults, resulting in a worldwide prevalence of LLD. The clinical phenotypes between LLD and adult depression differ in terms of symptoms, comorbid physical diseases, and coexisting cognitive impairments. Many pathological factors such as the imbalance of neurotransmitters, a decrease in neurotrophic factors, an increase in β-amyloid production, dysregulation of the hypothalamic-pituitary-adrenal axis, and changes in the gut microbiota, are allegedly associated with the onset of LLD. However, the exact pathogenic mechanism underlying LLD remains unclear. Traditional selective serotonin reuptake inhibitor therapy results in poor responsiveness and side effects during LLD treatment. Neuromodulation therapies and complementary and integrative therapies have been proven safe and effective for the treatment of LLD. Importantly, during the COVID-19 pandemic, modern digital health intervention technologies, including socially assistive robots and app-based interventions, have proven to be advantageous in providing personal services to patients with LLD.

Factors related to the accumulation of healthy behavior among older adults attending primary Health Care

The adoption and maintenance of healthy behaviors contribute for its accumulation throughout life, which require more than information disclosure and recommendations. Biopsychosocial factors may work as barriers to adherence to healthier behaviors, and yet have been underexplored. The objective was to investigate the factors related to the accumulation of healthy behavior among older adults attending Primary Health Care. Cross-sectional analysis with 201 older adults from baseline of Longitudinal Investigation of Functioning Epidemiology (LIFE) was performed in a Southeastern Brazilian city. The Healthy Behavior Score (HBS), ranging from 0 to 8, was calculated by the sum of the following habits: Physical activity practice, healthy eating, water consumption, night sleep time, not smoking, not drinking alcohol, frequent social relations, and spirituality. A linear multivariate regression was performed to test the influence of biopsychosocial aspects on HBS, with 95% confidence interval. Higher number of healthy behaviors was related to high social support, better cognitive status, less depressive symptoms and lower functional performance. Additionally, age and resilience score were correlated to healthy behaviors, which were higher among women and those with sufficient income. Multivariate analysis revealed depressive symptoms, functional performance and education as independent predictors of HBS. Depressive symptoms, functional performance and education are predictors of accumulation of health behaviors, independently of health status, contextual and sociodemographic aspects. Higher social support partially contributed to the higher number of healthy behaviors, and should be considered in public health policies for healthy longevity.