Experimental gerontology
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Experimental gerontology · Jun 2011
Comparative StudyAging effects on the control of grip force magnitude: an fMRI study.
Functional neuroimaging techniques have allowed for investigations into the mechanisms of age-related deterioration in motor control. This study used functional Magnetic Resonance Imaging (fMRI) to investigate age related differences in the control of grip force magnitude. Using an event-related design, fMRI scans were completed on 13 older adults, and 13 gender matched younger adults, while using their dominant hand to squeeze a rubber bulb for 4s at 10%, 40% or 70% of their maximum voluntary contraction. ⋯ The 7 clusters that showed significant differences tended to be areas that are involved in visual-spatial and executive processing. The results of this study revealed that older adults require significantly higher activation of several areas to perform the same motor task as younger adults. Higher magnitudes of the BOLD signal in older adults may represent a compensatory pattern to counter age related deterioration in motor control systems.
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Experimental gerontology · Apr 2011
ReviewRole of advanced glycation end products (AGEs) and receptor for AGEs (RAGE) in vascular damage in diabetes.
A non-enzymatic reaction between ketones or aldehydes and the amino groups of proteins, lipids and nucleic acids contributes to the aging of macromolecules and to the development and progression of various age-related disorders such as vascular complications of diabetes, Alzheimer's disease, cancer growth and metastasis, insulin resistance and degenerative bone disease. Under hyperglycemic and/or oxidative stress conditions, this process begins with the conversion of reversible Schiff base adducts, and then to more stable, covalently-bound Amadori rearrangement products. Over a course of days to weeks, these early glycation products undergo further reactions and rearrangements to become irreversibly crossed-linked, fluorescent protein derivatives termed advanced glycation end products (AGEs). ⋯ These observations suggest that the AGE-RAGE system is a novel therapeutic target for preventing diabetic vascular complications. In this paper, we review the pathophysiological role of the AGE-RAGE-oxidative stress system and its therapeutic intervention in vascular damage in diabetes. We also discuss here the potential utility of the restriction of food-derived AGEs in diabetic vascular complications.
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Experimental gerontology · Mar 2010
Açai palm fruit (Euterpe oleracea Mart.) pulp improves survival of flies on a high fat diet.
Reducing oxidative damage is thought to be an effective aging intervention. Açai, a fruit indigenous to the Amazon, is rich in phytochemicals that possesses high anti-oxidant activities, and has anti-inflammatory, anti-cancer and anti-cardiovascular disease properties. However, little is known about its potential anti-aging properties especially at the organismal level. ⋯ Furthermore, açai increased the lifespan of oxidative stressed females caused by sod1 RNAi. This suggests that açai improves survival of flies fed a high fat diet through activation of stress response pathways and suppression of Pepck expression. Açai has the potential to antagonize the detrimental effect of fat in the diet and alleviate oxidative stress in aging.
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Experimental gerontology · Dec 2009
Site-specific bone loss in senescence-accelerated mouse (SAMP6): a murine model for senile osteoporosis.
The senescence-accelerated mouse strain P6 (SAMP6) is a model of senile osteoporosis, which possesses many features of senile osteoporosis in humans. So far, little is known about the systemic bone microstructural changes that occur at multiple skeletal sites. In this study, we therefore, investigated site (vertebra, femur and tibia) dependence of bone microstructure and bone mineral density (BMD) in SAMP6 and the normal control mouse (SAMR1) at 5 and 12months of age using quantitative micro computed tomography (micro-CT) and image analysis software. ⋯ Increased marrow area and periosteal perimeter were investigated, though the cortical area and cortical thickness had no marked changes in the mid-tibial and mid-femoral cortical bones. These results indicate that bone microstructural properties in SAMP6 are remarkably heterogeneous throughout the skeleton, which is analogous to changes that occur in human bones. These findings further validate the relevance of SAMP6 as a model of senile osteoporosis.
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Experimental gerontology · Aug 2009
Associations of neutrophil and monocyte counts with frailty in community-dwelling disabled older women: results from the Women's Health and Aging Studies I.
Frailty is an important geriatric syndrome that predicts disability and mortality. Substantial evidence suggests that inflammation marked by elevated IL-6 levels and total white blood cell (WBC) counts contribute to this syndrome. However, the relationships of WBC subpopulations, the important inflammatory and immune cells, with frailty have not been investigated. ⋯ In addition, the identified associations were independent of IL-6. No significant associations of lymphocyte, eosinophil, or basophil counts with frailty were observed. These findings provide initial insight into potential roles of neutrophils and monocytes in the pathogenesis of frailty and a basis for further investigation into their function and regulation in frail older women.