Self-management of mood and/or anxiety disorders through physical activity/exercise

Fuel poverty and mental health in a COVID-19 context

Fuel poverty is a widespread problem which affects people's health and has serious economic and social repercussions. Mental health has been adversely affected by the COVID-19 pandemic and appears to be particularly influenced by fuel poverty. We analyze this relationship while highlighting the unequal vulnerability of individuals in the population. We first built a novel database of 4194 representative observations of the French adult population. We then used a conditional mixed-process model to quantify the causal effect of fuel poverty on mental health using instrumental variables to overcome potential endogeneity. We prove the robustness of this causal effect by providing different sensitivity tests. Our results show that being fuel poor decreases the mental health score by 6.3 points out of 100. Fuel poverty also increases the depression score by 5.35 points, the anxiety score by 6.48 points, and decreases the social health score by 6.82 points. Our results show that tackling energy poverty can lead to positive spillover effects to improve mental health. Mitigation policies to provide energy-efficient housing should also become a priority to address climatic and economic hazards in the long term because they imply co-benefits in health.

The influence of marathon running on resting-state EEG activity: a longitudinal observational study

Physical activity (PA) has positive effects on various health aspects and neuronal functions, including neuronal plasticity. Exceeding a certain exercise frequency and duration has been associated with negative effects. Our study investigated the effects of excessive PA with a marathon run (MA) and regular PA (training and recovery phases) on electrocortical activity, as measured by electroencephalography (EEG). Thirty healthy marathon runners (26 male, 45 ± 9 yrs) were enrolled in the study. Four resting-state 32 channel EEG recordings were conducted: 12-8 weeks before MA (T-1), 14-4 days prior to MA (T0), 1-6 days after (T2), and 13-15 weeks after MA (T3). Power spectrum analyses were conducted using standardized Low-Resolution Electromagnetic Tomography (sLORETA) and included the following frequency bands: delta (1.5-6 Hz), theta (6.5-8.0 Hz), alpha1 (8.5-10 Hz), alpha2 (10.5-12.0 Hz), beta1 (12.5-18.0 Hz), beta2 (18.5-21.0 Hz), beta3 (21.5-30.0 Hz), and total power (1.5-30 Hz). Statistical nonparametric mapping showed reduced power both in the alpha-2 (log-F ratio = - 0.705, threshold log-F ratio =  ± 0.685, p < 0.05) and in the delta frequency band (log-F ratio = -0.699, threshold log-F ratio =  ± 0.685, p < 0.05) in frontal cortical areas after MA (T2 vs. T0). These effects diminished at long-term follow-up (T3). The results can be interpreted as correlates for subacute neuroplasticity induced by strenuous and prolonged PA. Although previous studies reported an increase in alpha frequency during and directly postexercise, the adverse observation a few days after exercise cessation suggests counterregulatory mechanisms, whose complex origin can be suspected in subcortical circuits, changes in neurotransmitter systems and modulation of affectivity.

Barriers to using physical exercise as an intervention within inpatient mental health settings: A systematic review

Service providers find it difficult to implement Physical Exercise (PE) strategies in routine care within inpatient mental health settings even though they perceive it to be an effective therapy, with a robust evidence base. Identifying barriers that exist can assist with the development of future interventions and support PE services being introduced into mental health inpatient settings. The aim of this systematic review was to synthesise the evidence on the barriers or perceived barriers that exist amongst service users and providers when incorporating PE as an intervention within inpatient mental health settings. Using a narrative synthesis approach, four main themes were identified: (i) Barriers relating to service users' mental and physical health, (ii) Factors relating to service providers, (iii) Environmental factors and (iv) Cultural factors. Both service users and providers need more knowledge on implementing PE in inpatient mental health settings. Tailored programmes for service users are warranted, with specialist roles for staff developed.

Personal and Professional Physical Activity Practices among Sports Medicine Physicians

ABSTRACT

Less than a quarter of the population achieves the recommended Physical Activity Guidelines for Americans. Physicians who achieve the guidelines themselves may be more likely to promote them to patients given strong evidence physicians' personal health habits influence their patient counseling practices. We surveyed primary care and sports medicine specialty physicians about personal exercise habits and beliefs and patient counseling practices. Sports medicine physicians were significantly more likely to meet the Physical Activity Guidelines for Americans and believe that as physicians, they have an obligation to do so. They also were more likely to ask about, counsel, and refer patients to physical activity resources than other primary care physicians. Our results are consistent with previous evidence that physicians' personal habits influence their practice recommendations. This provides support that physicians' personal beliefs about the importance of exercise and sense of obligation to achieve recommended levels themselves plays a strong role in their patient care practices.

Characteristics Associated with Self-Reported Exercise among US Adults Age ≥50 Years with Self-Reported Pain in the Past Four Weeks Who Used an Opioid

The number of older adults in the United States is growing, alongside the number of older adults experiencing some sort of pain and using opioids. Exercise is an important pain management and pain prevention strategy. However, little is known about the factors associated with exercise among United States adults ≥50 years old with pain who use opioids. This retrospective cross-sectional database study aimed to identify characteristics associated with self-reported frequent exercise (moderate- to vigorous-intensity exercise ≥30 min five times a week) in United States adults ≥50 years old with pain in the past four weeks who had also used an opioid. The study used 2020 Medical Expenditure Panel Survey data and logistic regression models. Analyses maintained the structure of the complex survey data and were weighted to obtain nationally representative estimates. Significantly associated variables with frequent exercise in the fully adjusted analysis included being aged 60-69 (versus ≥80 years, adjusted odds ratio [AOR] = 2.3, 95% confidence interval [CI] = [1.1-5.1]), having excellent/very good/good (versus fair/poor) self-perceived health (AOR = 2.4, 95% CI = [1.3-4.2]), normal/underweight (versus obese (AOR = 2.1, 95% CI = [1.1-3.9])), overweight (versus obese (AOR = 1.7, 95% CI = [1.0-2.9])), and having little (versus extreme) pain (AOR = 2.4, 95% CI = [1.0-5.7]). A secondary finding was that 35.7% considered themselves frequent exercisers, while the remaining 64.3% did not consider themselves frequent exercisers. In future, these findings can be used to personalize pain management strategies and encourage greater levels of exercise among this population.

A 'health message' on sustainable physical and mental health for the prolonged COVID-19 and other pandemics

The world has been living with another pandemic physical inactivity (PI) and sedentary behavior (SB) and of other nature for years. As social measures to prevent the spread of COVID-19 have been strengthened, the physical activity (PA) barrier has been hit and the PI/SB pandemic has been exacerbated, and in the current situation, triggered by its prolonged period, it is emerging as a problem to be considered in order to combat the PI/SB pandemic through PA and to maintain continuous physical and mental health. This review aims to summarize existing and recent studies on the effects of PA/SB on physical and mental health in preparation for the context of prolonged COVID-19 and provides an easy and fun way to motivate, access PA, and PA recommendations for maintaining physical and mental health. We performed search strategies on PubMed, Medline, Scopus, and Google Scholar databases, and used a literature review of the current available literature on the COVID-19 and the effects of PI, SB, and PA on physical and mental health. The clinical relevance of this review shows that integrating PA into daily life and reducing prolonged sitting time is an important strategy for continuing a healthy life physically and mentally. As a result, for those who have not yet incorporated exercise as part of their daily routine, fun and easy access to PA suggests that in the long run, may be an opportunity to implement newer habits. In addition, in an emergency such as the COVID-19 quarantine period or other pandemics, it is essential for one to maintain health through PA at home, and underscore the 'health message' of the current review that reducing SB, progressively increasing PA, and doing more PA regularly in the current context prolonged COVID-19 can bring significant benefits to long-term habits and physical and mental health.

[Association between physical activity and apathy among community-dwelling older adults]

AIM

To determine the association between physical activity and apathy in community-dwelling older adults.

METHODS

This was a cross-sectional study. Apathy was assessed using three sub-items from the Geriatric Depression Scale 15 (GDS-3A) on apathy syndrome. Physical activity was measured using a wrist-worn accelerometer. Exercise intensity was classified as sedentary behavior, light-intensity physical activity, or moderate-to-vigorous-intensity physical activity. A logistic regression analysis was used to examine the association between apathy and physical activity for each exercise intensity level.

RESULTS

Seven-hundred and eighty-four participants (age 72.7±5.9 years old) were included. Of those, 103 (13.1%) were in the apathy group. A multivariate analysis adjusted for demographic factors revealed that decreased total physical activity (odds ratio [OR] = 0.947, 95% confidence interval [CI] = 0.912-0.984, p = 0.005), light-intensity physical activity (OR = 0.941, 95% CI = 0.899-0.985, p = 0.009), and increased sedentary behavior (OR = 1.002, 95% CI = 1.001-1.003, p = 0.007) were associated with a greater OR of apathy, although moderate-to-vigorous-intensity physical activity was not significant (OR = 0.916, 95% CI = 1.826-1.017, p = 0.100). However, in the final model adjusted for depressive symptoms and functional factors, the association was not found to be significant, and a strong association was observed between depressive symptoms and apathy.

CONCLUSION

Physical activity in older adults with apathy symptoms was decreased in this study. However, the associations seemed to be strongly affected by depressive symptoms, and physical activity was not independently associated with apathy.

Association of mood disorder with cardiometabolic multimorbidity trajectory and life expectancy, a prospective cohort study

BACKGROUND

Cardiometabolic diseases (CMDs) including hypertension, coronary heart disease, diabetes and stroke, are always combined with each other, leading to cardiometabolic multimorbidity (CMM). Mood disorder was associated with onset of CMD. However, the impact of mood disorder on the transition from single CMD to CMM was poorly understood.

METHODS

A total of 95,351 participants with single CMD, with median age of 59 (range 40 to 71) years from UK Biobank were enrolled at baseline. Competing risk regression models were used to estimated hazard ratios (HRs) and 95 % confidence intervals (CIs) of association between mood disorder categories and progress from single CMD to CMM. Association of mood disorder with mortality, and life expectancy differences were also calculated by flexible parametric proportion-hazard models.

RESULTS

Relative associations were observed between mood disorder and the progress from first onset of CMD to CMM. Adjusted HRs for progress to CMM from those with comorbid CMD plus depression or bipolar were increased (depression: 1.23 [1.19 1.27]; bipolar: 1.47 [1.31 1.66]), compared with those with the sole CMD. Mood disorder also had impact on all-cause mortality (depression: 1.17 [1.10 1.24]; bipolar: 2.03 [1.74 2.32]) and reduced life expectancy estimates for those with single CMD.

LIMITATIONS

This cohort primarily comprises White individuals. Covariates only measured at baseline and assumed unchanged during follow-up.

CONCLUSIONS

Mood disorder conferred greater hazard on the CMM and mortality outcome. This study highlighted the importance of depression and bipolar in disease progression, from single CMD, to multimorbidity or mortality.

A qualitative analysis of facilitators and barriers to physical activity among patients with moderate mental disorders

Aim

The current study aims to qualitatively identify determinants, barriers and facilitators of physical activity among a population with mental health disorders.

Subject and methods

Seventeen participants with moderate mental disorders were recruited. Semi-structured interviews were conducted to identify physical activity facilitators and barriers. Data were organized and analysed in ATLAS.ti, mainly based on a generic qualitative research approach.

Results

Most participants found physical activity important and expressed a positive attitude towards it. In general, higher self-efficacy and more social support were beneficial for participants' physical activity levels. Reasons/facilitating factors to be more physically active were: having fun, good weather, progress, routine, self-compassion and a stimulating environment. Barriers were not having fun, being busy, mental complaints, lack of energy, procrastination and physical complaints.

Conclusion

Future interventions could promote physical activity among people with moderate mental disorders to help them identify and overcome barriers. The newly identified determinant 'self-compassion' could be an interesting target for promoting physical activity in this group of people with moderate mental disorders.

Telemedicine as a Tool to Improve Medicine Adherence in Patients with Affective Disorders - A Systematic Literature Review

Affective disorders are a common psychological impairment. A major problem with respect to treatment is medication non-adherence. eHealth interventions are already widely used in the treatment of patients living with affective disorders. The aim of this systematic literature review is to obtain the current scientific evidence to eHealth as a tool to improve medication adherence in patients with affective disorders. A systematic search was performed across PubMed, Cochrane Library, Web of Science and PsycInfo. Studies in English and German published between 2007 and 2020 were included. The review followed the PRISMA guidelines and were performed with the CADIMA online tool. A total of 17 articles were included in this review. Eleven studies were randomized controlled trials, two were controlled clinical trials, and four had a pre-/post-design. Three different types of interventions could be identified: internet-based self-management programs (n=4), multi-faceted interventions addressing different dimensions of medication adherence (n=4), and single-faceted interventions (n=9) comprising four mobile interventions and five telehealth interventions. Eleven interventions addressed patients with (comorbid) depressions and six addressed patients with bipolar disorders. Six interventions showed a statistically significant positive effect on medication adherence. None of the studies showed a statistically significant negative effect. All interventions which had a statistically significant positive effect on medication adherence involved personal contacts between therapists and patients. All included eHealth interventions are at least as effective as control conditions and seems to be effective for patients with depression as well as with bipolar disorders. Personal contacts seem to improve the effectiveness of eHealth interventions. eHealth interventions are an effective way to improve medication adherence in patients with affective disorders. In rural or underserved regions, eHealth can supplement usual care interventions on medication adherence by expanding access. More analyses are needed in order to understand determinants for the effectiveness of eHealth interventions on medication adherence enhancement.

Association between health behaviors and depression: findings from the 2019 Brazilian National Health Survey

OBJECTIVE

To analyze the association of depression with various health behaviors and to verify if they differ according to gender or income.

METHODS

This is a cross-sectional study based on data of 65,803 Brazilian adults (18-59 years old) interviewed in the National Health Survey, conducted in 2019. Presence or absence of depression was evaluated using the Patient Health Questionnaire (PHQ)-9. The prevalence of smoking, alcohol consumption, physical activity, sedentary lifestyle and food indicators were estimated according to the presence of depression. Stratified analyses were made according to sex and income, and prevalence ratios were estimated using the Poisson Regression.

RESULTS

We found a significant association between depression and all indicators studied, except occasional alcohol consumption. Depression was associated with heavy episodic drinking and insufficient consumption of fruits and vegetables only in women. In men, the associations of depression with sedentary lifestyle and with being a former smoker were stronger than in women. The occasional consumption of alcohol was more prevalent only in men without depression. The analysis stratified by income showed that the association of depression with physical inactivity is stronger in the higher-income group, while with heavy episodic drinking is only significant in the lower-income stratum.

CONCLUSION

The results point to the need to consider mental health in programs aimed at reducing harmful health behaviors and the specificity of sociodemographic groups.

Exploring the Association Between Sport Participation and Symptoms of Anxiety and Depression in a Sample of Canadian High School Students

The mental health benefits of physical activity may relate more to the context of the behavior, rather than the behavior of being active itself. The association between varsity sport (VS) participation, depression, and anxiety symptoms was explored using data from 70,449 high school students from the Cannabis use, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behavior study. The model adjusted for potential covariates; interactions by sex and participation in outside of school sport (OSS) were explored. Overall, 70% and 24% of respondents met or exceeded cutoff values for depression and anxiety, respectively. Students participating in VS had lower symptoms of anxiety and depression compared with nonparticipants. Results were consistent regardless of OSS participation; associations were strongest among students who participated in both VS and OSS and males. Participation in VS may prove beneficial for the prevention and/or management of depression or anxiety symptoms, particularly among males. An additive beneficial effect of OSS on depression and anxiety scores may exist.

Physical activity and sedentary behaviour counselling: Attitudes and practices of mental health professionals

Background

Despite recent interest in the mental health benefits of increasing physical activity (PA) and reducing sedentary behaviour (SB), little is known about PA and SB counselling provided by mental health professionals. Therefore, the aim of this study was to explore the attitudes and practices of mental health professionals in recommending more PA and less SB to their clients.

Methods

Quantitative data were collected using a modified version of the Exercise in Mental Illness Questionnaire in a sample of 17 Australian mental health professionals. The collected data were reported using percentages (for categorical data) and means and standard deviations (for numerical data). Additionally, in focus group discussions, 10 mental health professionals provided in-depth information about their clinical practice, facilitators, and perceived barriers in recommending more PA and less SB. They also provided suggestions on how to potentially improve their PA and SB counselling practices. The focus groups were audio-recorded, transcribed and analysed using thematic analysis.

Results

Only 35.3% of participants have undergone formal training in recommending PA in the treatment of mental illness. Most participants (64.7%) ranked PA counselling among the top three types of mental health treatment. All participants reported recommending PA to their clients at least “occasionally”, while 88% of them also provided SB counselling. However, the recommendations provided were usually not specific. The most commonly reported barriers for providing PA and SB counselling were a lack of knowledge and confidence. Participants also believed that, if they were more active themselves, they would be in a better position to recommend PA to their clients, by sharing their own experience of evidence-informed strategies designed to increase PA and reduce SB.

Conclusion

The findings of this study indicate that mental health professionals commonly provide generic PA and SB counselling to their clients. PA and SB counselling in the mental health setting could be improved by: including training on PA and SB counselling in formal education and continued professional training for mental health professionals; implementing interventions to increase PA and reduce SB among mental health professionals themselves; and ensuring support from an exercise or PA promotion specialist as a part of a multi-disciplinary approach to mental health care.

The impact of sitting time and physical activity on mental health during COVID-19 lockdown

Objective

The primary aim of this study was to investigate the association between physical activity (PA) and sitting time on adults’ mental health (i.e., depression, anxiety and wellbeing) and the influence of mediators and confounders.

Methods

An online survey was disseminated in the UK between May and June 2020. A total of 284 participants (33.5 ± 12.4 years) self-reported their PA, sitting time and mental health through validated questionnaires.

Results

Multiple stepwise regression analysis revealed that being of younger age, female, on a lower income, with one or more comorbid health conditions, with a previous diagnosis of mood disorder and increased sitting time independently correlated with higher depression scores (F (13,219) = 12.31, p < 0.001), and explained 42% of the variance. Similar results were found for wellbeing where socio-demographic, health outcomes and sitting time influenced the subjective wellbeing (F (14,218) = 5.77, p < 0.001, 27% variance), although only socio-demographic and health outcomes contributed to the variation in anxiety score (F (13,219) = 7.84, p < 0.001, 32% variance). PA did not explain variation when sitting time was taken into account in any of the models. Combined analysis revealed that participants with lower sedentary time (< 8 h) and with both low or moderate and high PA presented a significantly lower depression score [low PA: (B = −2.7, 95% CI −4.88, −0.52); moderate and high PA (B = −2.7, −4.88, −0.52)].

Conclusion

Sitting time was strongly associated with adverse mental health during COVID-19 lockdown and should be considered in future public health recommendations.

Improving Depressive Symptoms through Personalised Exercise and Activation (IDEA): Study Protocol for a Randomised Controlled Trial

Individuals who suffer from depressive symptoms experience a substantial impact on psychosocial functioning, physical health, mortality, and quality of life. In the search for therapeutic strategies, exercise has been found to play a relevant part in its treatment. However, the promotion of exercise entails adherence difficulties that arose out of the tendency towards sedentarism led by symptomatology. Personalised exercise plans on top of usual care have the potential to enhance behavioural changes and mental health. The present study aims at evaluating the changes in functioning deriving from a blended intervention merging a psychological intervention with a personalised exercise programme based on medical assessment. We will conduct a three-arm randomised controlled trial in which 172 participants suffering from mild–moderate depressive symptoms will be allocated to Intervention A (personalised exercise group programme + app with motivational messages), B (personalised exercise group programme + app with no motivational messages) or control group (app with no motivational messages). Data regarding global functioning, well-being, symptoms, physical activity, and exercise capacity will be collected at baseline, 4, 12, and 36 weeks. The results of this trial will provide information about whether this physical activity support programme may be efficient for improving mental and physical health outcomes. Trial registration: ClinicalTrials.gov NCT04857944 (accessed on 15 April 2021). Registered April 2021.

Exercise prescription for people with mental illness: an evaluation of mental health professionals' knowledge, beliefs, barriers, and behaviors

OBJECTIVE

The aim of this study was to understand the knowledge, beliefs, barriers, and behaviors of mental health professionals about physical activity and exercise for people with mental illness.

METHODS

The Portuguese version of The Exercise in Mental Illness Questionnaire was used to assess knowledge, beliefs, barriers, and behaviors about exercise prescription for people with mental illness in a sample of 73 mental health professionals (68.5% women, mean age = 37.0 years) from 10 Psychosocial Care Units (Centros de Atenção Psicossocial) in Porto Alegre and Canoas, state of Rio Grande do Sul, Brazil.

RESULTS

Most of respondents had received no formal training in exercise prescription. Exercise ranked fifth as the most important treatment, and most of the sample never or occasionally prescribed exercise. The most frequently reported barriers were lack of training in physical activity and exercise prescription and social stigma related to mental illness. Professionals who themselves met recommended physical activity levels found fewer barriers to prescribing physical activity and did so with greater frequency.

CONCLUSION

Exercise is underrated and underused as a treatment. It is necessary to include physical activity and exercise training in mental health curricula. Physically active professionals are more likely to prescribe exercise and are less likely to encounter barriers to doing so. Interventions to increase physical activity levels among mental health professionals are necessary to decrease barriers to and increase the prescription of physical activity and exercise for mental health patients.

An Internet-based survey of the dance fitness program OULA

Background:

OULA is a high-energy dance workout to top 40 hits that is inspired by yoga and non-impact aerobics. Created in Missoula, Montana, the program has been gaining national and international popularity. To understand the demographic composition, reasons for attending OULA, and experiences with depression/anxiety, we conducted an Internet-based survey.

Methods:

A pilot descriptive cross-sectional Internet-based survey was created in Qualtrics and distributed through social media and flyers.

Results:

The 38-item survey received responses from 302 participants. Current OULA participants chose “exercise” as the primary reason for attending (40.2%, 95% confidence interval: 33.3–48.2), followed by “stress relief/improve mood” (28.8%, 95% confidence interval: 23.0–35.6). Participants listed “stress relief/improve mood” as the most common secondary (35.6%, 95% confidence interval: 29.0–43.2) and tertiary (38.6%, 95% confidence interval: 31.7–46.7) reason for attending OULA. A majority of the participants said that OULA makes them feel like part of a community (93.2%, 95% confidence interval: 82.5–105.1) and increases their energy outside of class (80.1%, 95% confidence interval: 70.2–91.1). In our sample, 12.5% (95% confidence interval: 8.8–17.1) and 9.0% (95% confidence interval: 5.9–12.9) were currently taking antidepressants and anxiolytics, respectively.

Conclusion:

These results suggest that current OULA participants are already using the program to relieve stress or improve mood. Further research should be conducted to understand the relationship between OULA and depression/anxiety.

Introduction

We are pleased to bring you the second of two special issues on mood and anxiety disorders focussing on data from the 2014 Survey on Living with Chronic Diseases in Canada-Mood and Anxiety Disorder Component (SLCDC-MA). In December of 2016, we published the first issue, which included three articles describing various aspects of Canadian adults with a self-reported diagnosed mood and/or anxiety disorder including their sociodemographic characteristics, health status, activity limitations and level of disability and factors associated with well-being. The three articles in this (second) issue investigate topics related to the management of these disorders. Collectively, the articles explore key sociodemographic factors known to influence health-related outcomes and discuss strategies aimed at promoting the recovery and well-being of Canadian adults with a self-reported mood and/or anxiety disorder diagnosis.

Heme Oxygenase-1 Activity as a Correlate to Exercise-Mediated Amelioration of Cognitive Decline and Neuropathological Alterations in an Aging Rat Model of Dementia

Alzheimer's disease (AD) is a neurodegenerative disorder with cognitive impairment. Physical exercise has long been proven to be beneficial in the disorder. The present study was designed to examine the effect of voluntary exercise on spatial memory, imaging, and pathological abnormalities. Particular focus has been given to the role of heme oxygenase-1 (HO-1)—an important cellular cytoprotectant in preserving mental acuity—using an aging rat model of dementia. Male and female Wistar rats were segregated into six groups—namely, (i) aged sedentary (control) females (ASF, n = 8); (ii) aged sedentary (control) males (ASM, n = 8); (iii) aged running females (ARF, n = 8); (iv) aged running males (ARM, n = 8); (v) young control females (YCF, n = 8); and (vi) young control males (YCM, n = 8). Rats in the ARF and ARM groups had free access to a standardized inbuilt running wheel during the 3-month evaluation period. Spatial memory was investigated using the Morris Water Test, imaging and pathological alterations were assessed using positron emission tomography (PET) imaging and histopathological examinations (H&E, Congo red staining), respectively, and HO-1 enzyme activity assays were also conducted. The outcomes suggest that voluntary physical exercise mitigates impaired spatial memory and neuropathological changes exhibited by the aging sedentary group, via elevated HO-1 activity, contributing to the antioxidant capacity in the aging brain.