Current Aging Science (v.9, #4)

Meet Our Editorial Board Member by Sataro Goto (239-239).

Impact of Exercise Training on Physiological Measures of Physical Fitness in the Elderly by Goncalo V. Mendonca, Pedro Pezarat-Correia, João R. Vaz, Luís Silva, Isabel D. Almeida, Kevin S. Heffernan (240-259).
Background: Older persons are the fastest growing segment of the population living in the Western hemisphere. Longevity comes at a price, including a higher rate of morbidity, functional and mental disability and the eventual loss of independence. Physical inactivity further aggravates the decline in physiological function along the aging process. Therefore, the promotion of regular exercise may be seen as one of the main non-pharmacological approaches that should be recommended to older adults.
Methods: We performed a comprehensive review on the interaction between exercise training and improved physical fitness in the elderly. Specifically, 175 papers describing the overall benefits of exercise training on the cardiovascular, neuromuscular and brain function of older adults were included. The effectiveness of training for improving quality of life at an older age was also reviewed.
Results: Exercise training can partially reverse the age-related physiological decline and enhance work capacity in the elderly. Numerous studies have shown that maintaining a minimum quantity and quality of physical exercise decreases the risk of cardiovascular mortality, sarcopenia, prevents the onset of osteopenia and even exerts a prophylactic role against neurodegeneration. The systemic physiologic effects are profound and may be directly linked to a favorable feedforward cycle whereby improved physiologic function begets improved physical function and so on.
Conclusion: We conclude that structured training programs should be designed to improve the physiological function in this population. Finally, the benefits of exercise training vary as a function of training volume and this relationship is independent of age and sex.

Micronutrient Intake in the Etiology, Prevention and Treatment of Osteosarcopenic Obesity by Owen J. Kelly, Jennifer C. Gilman, Youjin Kim, Jasminka Z. Ilich (260-278).
Background: Aging, chronic inflammation and/or many chronic conditions may result in loss of bone, loss of muscle and increased adiposity, manifested either overtly (overweight) or furtively as fat infiltration into bone and muscle. This combined condition has been identified as osteosarcopenic obesity. Micronutrients are required, not just to prevent deficiency diseases, but for optimal health and metabolic homeostasis. Further, micronutrients have multifunctional roles in the body. However, it is unknown if the micronutrient intake of the Western diet contributes to bone and muscle loss, increased adiposity, and ultimately osteosarcopenic obesity.
Objective: The aim of this review is to examine the micronutrient intake using US National Health and Nutrition Examination Survey (NHANES) data, and explore if the insufficiencies, or excesses present contribute to the development of osteosarcopenic obesity in aging.
Method: First NHANES food intake data from 2002-2012 were obtained and transposed to Microsoft Excel for analysis. A literature search of PubMed and Medline for human data using combinations and synonyms of osteoporosis, sarcopenia and obesity, and each mineral and vitamin indicated as insufficient by NHANES.
Results: NHANES data suggested phosphorus, calcium, magnesium, potassium, iron, and vitamins B6/B12/C/A/D/E and K were candidates for further evaluation. 170 articles were included.
Conclusion: While chronic single/multiple micronutrient insufficiency/excess is not studied in clinical trials, NHANES data suggest that they have existed for at least a decade. Examining the status and roles of those nutrients may be important to understanding the health issues associated with Western-type diets, including development of osteosarcopenic obesity.

Background: In this study, human neuroblastoma cells (IMR32) treated with Amyloid Beta Peptide (APβ), were used as model to evaluate the molecular basis of protective role of S100b, a neurotrophic factor and neuronal survival protein, highly expressed by reactive astrocytes close to amyloid deposition in the cortex of Alzheimer's patients. The aim of this work is to value the effect of S100b on ROS production in cells treated with Amyloid Beta Peptide and the subsequent influence on globin gene expression.
Method: In this study we investigated the effect of S100b on ROS production and on globin gene expression in human neuroblastoma cells (IMR32) treated with Amyloid Beta Peptide (APβ).
Results: Our results have shown that at nanomolar concentrations, S100b protects cells against AP mediated cytotoxicity and the protective mechanism could be related, almost in part, to the control of ROS production through an over expression of Myoglobin gene.
Conclusion: In light of our results, we speculate that over-expression of the Myoglobin gene could be read as a possible attempt of the cell to increase the scavengers of reactive oxygen species (ROS).

Smoking and Obesity Increase Airway Hyperesponsiveness Risk in the Elderly by Bruno Sposato, Marco Scalese, Manlio Milanese, Nicola Scichilone, Raffaele Scala, Antonio Perrella (284-294).
Objective: of our study was assessing whether smoking and obesity might affect airways hyperresponsiveness (AHR) differently in younger and older subjects and whether this influence might be due to their different impacts on baseline lung function values at different ages.
Methods: 3,903 consecutive adult subjects with normal lung function (1,920 males; mean age 35.1±16.2; median FEV1:97.3% of predicted [interquartile range (IQR):89.7-105.2] and FEV1/FVC: 84.6% of predicted [IQR:79.8-89.2]), having performed a methacholine test, were considered. They were subdivided into three groups according to age (18-39, 40-64 and 65 years) and into different sub-groups according to body mass index (BMI) and smoking habits, considering two AHR level cut-offs (PD201600 g and PD20800 g).
Results: PD20 was significantly lower (p<0.004) in obese subjects aged 18-39 years, in comparison to older patients. Smoking was an AHR risk factor for subjects aged 40-64 and especially for those aged >65 (OR: 12.786 [IQR: 1.450-112.753]; p<0.0001). Obesity caused an AHR risk only in older subjects (>65 years) (OR: 3.120 [IQR: 1.144-8.509]; p<0.0001). FEV1/FVC and FEF25-75% decreased progressively (p<0.001) with age in subjects with different weights/smoking habits. No reductions with age were observed in FEV1% and FVC% except for a significant FVC% decrease in older smokers compared to older non-smokers.
Conclusion: Smoking determined a progressively increasing AHR risk reaching its peak in the elderly. In younger obese individuals, AHR was higher than in obese elderly, whereas obesity was a higher AHR risk factor only in subjects aged >65 years. A small airway age-related reduction may cause the increased smoking/obesity induced AHR risk in older people.

Background: Balance deterioration in older adults limits their activities of daily living, community participation, and is a significant risk factor for falls. One contributory element to this functional decline is impairment of anticipatory postural adjustments (APAs).
Objectives: To evaluate the role and feasibility of a novel training program in improving APAs for balance control of older adults.
Method: Six older adults (73.3±5.0 years) were randomly assigned into the Experimental (EG) and Control groups (CG). The EG participated in four weeks of APA-focused training involving catching a medicine ball while standing. All subjects were exposed to predictable external and self-initiated perturbations before and after training. EMG activity of eight trunk and leg muscles was recorded bilaterally and muscle onsets were analyzed during the anticipatory phase of postural control. Clinical tests of balance (Timed-Up and Go, Single limb stance, and Activities-specific Balance Confidence scale) were implemented.
Results: Early onsets of APA activity prior to the external perturbations were seen in the EG following training. Moreover, early APA activity was observed in the EG prior to bilateral arm flexion, a task that was not a part of training, indicating a transfer of the learning effect of training. The improvement of APAs in the EG also resulted in improved performance on clinical outcome measures. There were no improvements seen in the CG for both the APA activity and the clinical balance tests.
Conclusion: The study outcome suggests that a four-week APA-based training program is feasible and could be effective in improving postural control, functional balance, mobility, and quality of life in older adults.

Age and High-Fat Diet Effects on Glutamine Synthetase Immunoreactivity in Liver and Hippocampus and Recognition Memory in Mice by Virawudh Soontornniyomkij, James P. Kesby, Benchawanna Soontornniyomkij, Jane J. Kim, Tatiana Kisseleva, Cristian L. Achim, Svetlana Semenova, Dilip V. Jeste (301-309).
Background: High-Fat Diet (HFD)-induced obesity may promote agerelated memory impairment via disturbances of ammonia-glutamine metabolism.
Objective: We studied the effects of age and long-term HFD exposure on Glutamine Synthetase (GS) expression in the liver and hippocampus and recognition memory in mice.
Methods: Adult (5-month-old) and aged (15-month-old) male C57BL/6 mice were exposed to control diet (CD, 14% calories from fat) or HFD (60% fat). Novel place recognition testing was conducted and tissue was collected after 4 and 5 months on HFD, respectively. Tissue GS expression levels were assessed using immunohistochemistry and image analysis.
Results: The obese mice developed moderate/severe hepatic steatosis. GS immunoreactivity was observed in perivenous hepatocytes and in hippocampal astrocytes and neuropil. Hepatic GS immunoreactivity density was higher in aged mice on HFD (n = 8) than CD (n = 13, P = 0.004). In aged mice, hippocampal GS immunoreactivity density was higher with HFD than CD (P = 0.037). In the novel place recognition test, aged mice were classified into impaired (n = 7) and unimpaired (n = 12), relative to adult mice (n = 22). Hippocampal GS immunoreactivity density was higher in impaired than unimpaired aged mice (P < 0.05).
Conclusion: Long-term exposure of aged mice to HFD was associated with increased GS expression in the liver and hippocampus. Novel place recognition impairment in aged mice was associated with increased hippocampal GS expression. These findings suggest that excess ammonia is involved in the age-related effects of HFD exposure and in neurotoxicity.

Background: While cognition is clearly affected by aging, it is unclear whether the process of brain aging is driven solely by accumulation of environmental damage, or involves biological pathways.
Methods: We applied quantitative image analysis to profile the alteration of brain tissues during aging. A dataset of 463 brain MRI images taken from a cohort of 416 subjects was analyzed using a large set of low-level numerical image content descriptors computed from the entire brain MRI images. The correlation between the numerical image content descriptors and the age was computed, and the alterations of the brain tissues during aging were quantified and profiled using machine learning.
Results: The comprehensive set of global image content descriptors provides high Pearson correlation of 0.9822 with the chronological age, indicating that the machine learning analysis of global features is sensitive to the age of the subjects. Profiling of the predicted age shows several periods of mild changes, separated by shorter periods of more rapid alterations. The periods with the most rapid changes were around the age of 55, and around the age of 65.
Conclusion: The results show that the process of brain aging of is not linear, and exhibit short periods of rapid aging separated by periods of milder change. These results are in agreement with patterns observed in cognitive decline, mental health status, and general human aging, suggesting that brain aging might not be driven solely by accumulation of environmental damage. Code and data used in the experiments are publicly available.