Current Aging Science - Volume 10, Issue 3, 2017

Background: Alzheimer's Disease (AD) and Parkinson's Disease (PD) are among the most common causes of dementia, which increasingly contribute to morbidity and mortality worldwide. A common hallmark in the pathogenesis of these two diseases is neuroinflammation, which is initially triggered by the presence of pathological structures associated with these disorders. Chronic neuroinflammation is sustained by persistent and aberrant microglial activation in the brain, which results in damage and death of neighboring cells, including neurons and glial cells. Two types of risk factors contribute to the development of AD and PD: non-modifiable risk factors and modifiable risk factors. Non-modifiable risk factors include genetic susceptibility that increases an individual's risk of developing the disease, whereas modifiable risk factors include a wide variety of health- and lifestyle-related factors that may be altered by changing individual behaviors. Method: Ovid Medline and PubMed databases were used to perform an ordered search of the peerreviewed research literature described in this review. Results: This review focuses on four modifiable risk factors including physical inactivity, vascular disease-related conditions, obesity and type two diabetes mellitus, all of which have been identified as risk factors for the development of AD and PD. Conclusion: We highlight that control of the modifiable risk factors is a valid approach for managing the increased incidence of AD and PD. We describe neuroinflammatory mechanisms, which are common to AD and PD that may link both these neurodegenerative diseases with the four common modifiable risk factors. Understanding neuroinflammatory mechanisms could help identify novel therapeutic targets for combating these neurodegenerative diseases.

Background: Parkinson's disease (PD) is a slow progressive neurodegenerative disease associated with abnormal function of extrapyramidal system. Although several biochemical and genetic defects are identified, increased oxidative stress and chronic inflammation are one of the earliest events that initiate and promote PD. Oxidative stress also participates in impaired nonmotor symptoms. The levels of microRNAs that are evolutionarily conserved single-stranded noncoding RNAs of approximately 22 nucleotide in length may have a role in PD. Method: Published studies on changes in the levels of microRNAs in PD were critically reviewed, and the role of Reactive Oxygen Species (ROS), pro-inflammatory cytokines, and antioxidants in regulating the levels of microRNAs was evaluated. Results: MicroRNAs levels were altered in PD. Downregulated microRNAs cause neurodegeneration by decreasing the levels of Nrf2 (nuclear transcriptional factor-2), mTOR (mammalian target of rapamycin), and DJ-1 and Parkin genes; and by increasing the levels of alpha-synuclein, RelA, Bim and Calpain-1, and A2AR (adenosine A2A receptor). Upregulated microRNAs cause degeneration of nerve cells by decreasing the levels of IGF-1 (Insulin Growth Factor-1), GRP78 (glucose regulated protein 78), DJ-1, and Hsc-70 (Heat- Shock Protein-70) that enhanced alpha-synuclein levels. ROS and pro-inflammatory cytokines cause neurodegeneration by altering the levels of microRNAs. Antioxidants that protect neurons by reducing oxidative stress and chronic inflammation altered the levels of microRNAs. Conclusion: Increased oxidative stress and chronic inflammation may cause neurodegeneration in PD by altering the levels of microRNAs and their target proteins. Antioxidants may provide neuroprotection by changing the levels of microRNAs and their target proteins.

Background: The aging of posture and balance function alters the quality of life in older people and causes serious problems in terms of public health and socio-economic costs for our modern societies. Method: This article reviews the various causes of imbalance and dizziness in the elderly, and considers how to prevent falls, and how to rehabilitate a faller subject in order to regain a good quality of life. Two effective ways of intervention are discussed, emphasizing the crucial role of physical activity and cognitive stimulation, classic or using the latest technical advances in virtual reality and video games. Results: Fall in the elderly result from aging mechanisms acting on both the sensorimotor and cognitive spheres. The structural and functional integrity of the peripheral sensory receptors and the musculoskeletal system deteriorate with age. The brain ages and the executive functions, memory, learning, cortical processing of information, sharing of attentional resources and concentration, are modified in the elderly. Psychological affective factors such as depression, anxiety and stress contribute also to speed up the sensorimotor and cognitive decline. The rehabilitation of the postural balance in the elderly must take into account all of these components. Conclusion: The aging of the population and the increased of lifespan are a challenge for our modern societies regarding the major health and socio-economic questions they raise. The fall in the elderly being one of the dramatic consequences of the aging equilibration function, it is therefore imperative to develop rehabilitation procedures of balance.

Background: Ageing is a natural phenomenon that has tremendous amount of control over normal physiological functions. Diabetes mellitus and ageing share common symptoms like stiffness and loss of functioning of tissues due to cross-liked proteins and free radicals. Glycated Haemoglobin (HbA1c) is often used as a stable cumulative index of glycemic control and has shown that even in non-diabetic adults, there is a steady increase in HbA1c levels with age. Aim of the study is to evaluate the strength of association of HbA1c with metabolic and cardiovascular ageing indices in subjects between the age group of 40 to 60 yrs. Method: A total of 220 subjects, with (n=110) and without (n=110) diabetes were assessed for the metabolic and cardiovascular ageing indices. BMI, waist hip ratio, fat percentage, Fasting blood sugar and HbA1c were assessed as metabolic ageing indices. The cardiovascular ageing indices measured were resting heart rate, blood pressure and heart rate variability. Results: Ageing indices were compared between subjects with and without diabetes using independent‘ t’ test and showed that the T2DM group exhibit significant accelerated ageing as compared to that of the controls. Pearson's and partial correlation coefficient was used to assess the association of HbA1c with the ageing indices without and with controlling for chronological age, indicated that, strength of association of levels of HBA1c with cardiovascular and other metabolic indices of ageing is statistically significant. Conclusion: The study concludes that the tightness of glycemic control has a significant impact on the biological ageing process

Background: Three-quarters of patients with major depressive disorder have late-onset depression. Late-onset depression is more often associated with cognitive impairment than earlyonset depression and evidences showed a relationship between vascular factors and late-life depression. Objectives: To compare cognitive functions between late-onset (≥60 years) and early-onset (<60 years) depression in elderly patients and to highlight the effect of vascular risk factors in elderly patients with late and early onset depression. Methods: This was a cross sectional, case control study with consecutive referral done on eighty elderly patients with depression who were recruited from Geriatric Outpatient Clinic of Psychiatry and Addiction Prevention Hospital, Al Kasr Al-Ainy, Cairo University. They were divided into two groups according to the age of onset of depression: Late Onset Depression (LOD) group and Early Onset Depression (EOD) group. They were cognitively assessed using ACE III, Framingham risk score for vascular risk assessment. Results: Late onset group had worse performance than early onset group regarding memory, verbal fluency, language, visuospatial abilities and had more vascular risk. Conclusion: Elderly patients with late onset depression had higher severity of depression as well as they were more cognitively affected regarding memory, verbal fluency, language, and visuospatial abilities. Vascular risk factors especially hypertension and diabetes mellitus were higher elderly patients with late onset depression and affects the severity of depression and degree of cognitive impairment.

Background: Older persons are overwhelmed with psychological stressors due to requirements related to the management of their health problems. The purpose of this study was to investigate physical, psychological and social wellbeing of older persons. Method: Cross-sectional explorative design used convenience sample of 1058 older persons in Jordan. Data was collected in regard to physical, psychological and social wellbeing using selfreported format. Results: The three most bothered physical symptoms are; pain in arms, legs, or joints; feeling tired or having low energy; and back pain with percentages of 71.5% (n=756), 69.6% (n=737), and 62.2% (n=754), respectively. Older persons had slight to mild level of depression (M = 17.9, SD =7.7), moderate to high level of life satisfaction (M=24.1, SD=5.6), moderate level perception of social support, and mild to moderate level psychological distress (M = 39.1 (SD = 11.3). Depression among participants has significant and positive association with sleep disturbance (r = .21, p < .001), psychological distress level (r =.50, p <.001). There was a significant difference between males and females in depression (t = -4.40, p <.001), psychological distress (t = -3.38, p <.001), life satisfaction (t = 2.09, p = .04) and sleep disturbances (t = -2.16, p = .03). Conclusion: Older persons are in need for periodic assessment for their psychosocial wellbeing in their routine checkups and visits to outpatients units. Research is needed to investigate impact of psychological and social wellbeing on other biological and health care related issues such as access and utilization of care and quality of life among older persons.

Background: Aging or senescence is a complex biological phenomenon. Artificially selected Drosophila for extended longevity is one of the experimental models used to understand the mechanisms involved in aging and to test various theories. Objective: To examine the life history traits and biochemical defenses in relation to aging in an extended longevity phenotype of Drosophila melanogaster. Methods: Life history traits viz., survivability, fecundity, development time, dry weight, wing size, lipid content, starvation, desiccation and cold resistances, locomotory ability, antioxidant enzyme activities and reactive oxygen species level between control and selected lines of D. melanogaster were investigated. Results: In our model of Drosophila, extended longevity is associated with no trade-off in fecundity and shows variable resistance to environmental stress such as starvation, cold and desiccation. Enhanced biochemical defense involving the antioxidant enzymes was positively correlated with longevity. Conclusion: Extended longevity phenotypes of Drosophila represent genomic plasticity associated with variable life history traits attributed to the genetic background of the progenitor population and the environment of selection. Oxidative stress resistance seems to be a significant factor in longevity.