Hyperbaric oxygen alleviates selective domains of cognitive and motor deficits in female 5xFAD mice.

Treatment of Alzheimer's disease (AD) has been limited to managing of symptoms or anti-amyloid therapy with limited results and uncertainty. Seeking out new therapies that can reverse the effects of this devastating disease is important. Hyperbaric oxygen (HBO) therapy could be such a candidate as it has been shown to improve brain function in certain neurological conditions. Furthermore, the role sex plays in the vulnerability/resilience to AD remains equivocal. An understanding of what makes one sex more vulnerable to AD could unveil new pathways for therapy development. In this study, we investigated the effects of HBO on cognitive, motor, and affective function in a mouse model of AD (5xFAD) and assessed protein oxidation in peripheral tissues as a safety indicator. The motor and cognitive abilities of 5xFAD mice were significantly impaired. HBO therapy improved cognitive flexibility and associative learning of 5xFAD females but not males, but HBO had no effect other aspects of cognition. HBO also reversed AD-related declines in balance but had no impact on gait and anxiety-like behavior. HBO did not affect body weights or oxidative stress in peripheral tissues. Our study provides further support for HBO therapy as a potential treatment for AD and emphasizes the importance of considering sex as a biological variable in therapeutic development. Further investigations into the underlying mechanisms of HBO's sex-specific responses are warranted, as well as optimizing treatment protocols for maximum benefits.

Neurodegenerative Disease: Roles for Sex, Hormones, and Oxidative Stress.

Neurodegenerative diseases cause severe impairments in cognitive and motor function. With an increasing aging population and the onset of these diseases between 50 and 70 years, the consequences are bound to be devastating. While age and longevity are the main risk factors for neurodegenerative diseases, sex is also an important risk factor. The characteristic of sex is multifaceted, encompassing sex chromosome complement, sex hormones (estrogens and androgens), and sex hormone receptors. Sex hormone receptors can induce various signaling cascades, ranging from genomic transcription to intracellular signaling pathways that are dependent on the health of the cell. Oxidative stress, associated with aging, can impact the health of the cell. Sex hormones can be neuroprotective under low oxidative stress conditions but not in high oxidative stress conditions. An understudied sex hormone receptor that can induce activation of oxidative stress signaling is the membrane androgen receptor (mAR). mAR can mediate nicotinamide adenine dinucleotide-phosphate (NADPH) oxidase (NOX)-generated oxidative stress that is associated with several neurodegenerative diseases, such as Alzheimer disease. Further complicating this is that aging can alter sex hormone signaling. Prior to menopause, women experience more estrogens than androgens. During menopause, this sex hormone profile switches in women due to the dramatic ovarian loss of 17ß-estradiol with maintained ovarian androgen (testosterone, androstenedione) production. Indeed, aging men have higher estrogens than aging women due to aromatization of androgens to estrogens. Therefore, higher activation of mAR-NOX signaling could occur in menopausal women compared with aged men, mediating the observed sex differences. Understanding of these signaling cascades could provide therapeutic targets for neurodegenerative diseases.

Metabolic risk profiles and associated risk factors among Vietnamese adults in Ho Chi Minh City.

BACKGROUND: A clustering of metabolic risk factors increases the likelihood of cardiovascular diseases. This study reports the metabolic risk profiles and the prevalence of metabolic risk factors and associated factors among Vietnamese adults in Ho Chi Minh City. METHODS: A cross-sectional study was carried out in a representative sample of adults aged 25-64 years in Ho Chi Minh City in 2005. Metabolic risk factors, including central obesity, elevated fasting glucose, elevated total cholesterol, and raised blood pressure, were collected to estimate their prevalence and association with socioeconomic and health-related behavioral risk factors. Multivariate logistic models were performed to examine the associations between socioeconomic and behavioral risk factors and the odds of having metabolic risk factors. RESULTS: The prevalence of individual risk components was: 28.9% high blood pressure, 18.3% central obesity, 16.8% high total cholesterol, and 6.4% high fasting glucose. There were significant gender differences in central obesity and high blood pressure. The prevalence of metabolic risk cluster (two or more risk factors) was 17.0% in men and 17.6% in women. The metabolic risk cluster appeared earlier in men, but women showed higher rates at older ages. Increasing age and household wealth were associated with the metabolic risk cluster across both genders, but additional risk factors in men were smoking in the past and in women education level and sitting and reclining time. CONCLUSIONS: Strategies to prevent metabolic risk factors through the prevention of abdominal obesity must be established for young adults and should include promoting physical activity, healthy eating, and preventing alcohol abuse and tobacco use.

Test-retest repeatability and relative validity of the Global Physical Activity Questionnaire in a developing country context.

BACKGROUND: The increasing prevalence of chronic lifestyle diseases in developing countries warrants reliable and valid surveillance of physical activity levels in the population. This study assesses the test-retest repeatability and criterion validity of the WHO-recommended Global Physical Activity Questionnaire (GPAQ) in Vietnamese adults during the dry and wet seasons. METHODS: In 2007 a representative sample of 169 adults (25-64 years) was recruited to determine the GPAQ reliability and validity. GPAQ assesses time and intensity of physical activities spent during a usual week. To assess short and long term reliability, participants completed the GPAQ twice during the dry season 2 weeks apart and again 2 months later during the wet season. For validation purposes, participants wore an accelerometer during the 7 days before the first and last GPAQ assessments. RESULTS: The total GPAQ score showed repeatability correlations of 0.69 after 2 weeks and of 0.55 after 2 months. Total GPAQ score and accelerometer data showed validity correlations of 0.34 and 0.20 in the dry and wet season, respectively. There was a difference in physical activity patterns between the dry and wet seasons. CONCLUSIONS: GPAQ is suitable for surveillance of physical activity among adults in Vietnam.

Prevalence and risk factors with overweight and obesity among Vietnamese adults: Caucasian and Asian cut-offs.

OBJECTIVE: To determine the prevalence and factors associated with overweight/obesity among adults in Ho Chi Minh City (HCMC) using Caucasian and Asian cut-offs. STUDY DESIGN: A cross-sectional survey. METHODS: In 2005, 1,971 adults aged 25-64 years in HCMC were randomly selected using a proportional to population size sampling method to estimate the prevalence of overweight and obesity, measured by body mass index (BMI) and waist circumference. Multivariable logistic models were used to examine associations between overweight/obesity and socioeconomic status, health-related behaviors, and biochemical indices of chronic disease risk. RESULTS: The prevalence of overweight and obesity using the Caucasian BMI cut-offs were 13.9% and 1.8% respectively, and those with the Asian BMI cut-offs were 27.5% and 5.7%, respectively. The abdominal adiposity rates were higher than the BMI overweight and obesity rates in women, but not in men. Increasing age, low education, high household wealth index, high levels of sitting and reclining time, cholesterol and high blood pressure were significantly associated with overweight and obesity. Current smoking and sedentary leisure time was significantly negatively associated with this status in men. CONCLUSION: Associations between overweight/obesity and metabolic disorders were evident using both cut-offs. Asian cut-offs identified more risk factors and therefore could be considered for defining at-risk groups. The results highlight the importance of intervention programs to prevent overweight/obesity in young adults.

The prevalence and correlates of physical inactivity among adults in Ho Chi Minh City.

BACKGROUND: Socioeconomic changes have led to profound changes in individuals' lifestyles, including the adoption of unhealthy food consumption patterns, prevalent tobacco use, alcohol abuse and physical inactivity, especially in large cities like Ho Chi Minh City (HCMC). The Stepwise Approach to Surveillance of Non-communicable Disease Risk Factors survey was conducted to identify physical activity patterns and factors associated with 'insufficient' levels of physical activity for health in adults in HCMC. METHODS: A cross-sectional survey was conducted in 2005 among 1906 adults aged 25-64 years using a probability proportional to size cluster sampling method to estimate the prevalence of non-communicable disease risk factors including physical inactivity. Data on socioeconomic status, health behaviours, and time spent in physical activity during work, commuting and leisure time were collected. Physical activity was measured using the validated Global Physical Activity Questionnaire (GPAQ). Responders were classified as 'sufficiently active' or 'insufficiently active' using the GPAQ protocol. Correlates of insufficient physical activity were identified using multivariable logistic regression. RESULTS: A high proportion of adults were physically inactive, with only 56.2% (95% CI = 52.1-60.4) aged 25-64 years in HCMC achieving the minimum recommendation of 'doing 30 minutes moderate-intensity physical activity for at least 5 days per week'. The main contributors to total physical activity among adults were from working and active commuting. Leisure-time physical activity represented a very small proportion (9.4%) of individuals' total activity level. Some differences in the pattern of physical activity between men and women were noted, with insufficient activity levels decreasing with age among women, but not among men. Physical inactivity was positively associated with high income (OR = 1.77, 95% CI = 1.05-2.97) and high household wealth index (OR = 1.86, 95% CI = 1.29-2.66) amongst men. CONCLUSION: Public health policies and programs to preserve active commuting in HCMC and to promote time spent in recreational physical activity in both genders and across all age groups, but especially among young adults, will be critical in any comprehensive national plan to tackle inactivity. Clear and consistent national recommendations about how much physical activity Vietnamese people need for preventing and managing non-communicable diseases should also be part of this population-wide promotional effort.