Experimental gerontology
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Experimental gerontology · May 2012
Comparative StudyLow survivorship of dauer larva in the nematode Caenorhabditis japonica, a potential comparative system for a model organism, C. elegans.
The nematode dauer larva (DL) is a non-aging diapause stage. The DL of the model nematode Caenorhabditis elegans has been studied as a model system for aging and longevity. However, information on DL in other nematode species is limited. ⋯ The fact that C. japonica DL cannot survive away from its insect host indicates that its longevity is increased by unknown factors derived from the host. Despite these significant differences between C. japonica and C. elegans, these two species are phylogenetically closely related (they are derived from a common ancestor). Therefore, C. japonica could be a good comparative system for C. elegans, and further physiological and molecular analyses of C. japonica DL may provide important information about the internal and external factors affecting the longevity of nematodes in general.
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Experimental gerontology · Apr 2012
Segmental variations in trabecular bone density and microstructure of the spine 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 the cervical, thoracic, and lumbar vertebrae. In this study, we therefore investigated segmental variations of vertebral trabecular bone mineral density (BMD) and three-dimensional microstructure in SAMP6 and the normal control mouse (SAMR1) at 12 months of age using quantitative micro computed tomography (micro-CT) and image analysis software. ⋯ These results indicate that vertebral trabecular bone microstructures are remarkably heterogeneous throughout the spine in both SAMR1 and SAMP6. The decrease of vertebral trabecular bone density in SAMP6 advanced faster caudally than cranially within the spine, similar phenomena were observed in humans. These findings highlight the relevance of SAMP6 for studies of vertebral fragility associated with senile osteoporosis.
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Experimental gerontology · Feb 2012
A single nucleotide polymorphism of the adenosine deaminase, RNA-specific gene is associated with the serum triglyceride level, abdominal circumference, and serum adiponectin concentration.
Single nucleotide polymorphisms (SNPs) of the adenosine deaminase, RNA-specific (ADAR) gene were reported to be associated with human longevity. There are possibilities that ADAR is associated with major risk factors of atherosclerotic cardiovascular diseases (CVD), such as hypertension, diabetes, dyslipidemia, and obesity. ⋯ The SNP in ADARB2 related to longevity is associated with metabolic disorders. This finding suggests that genetic factors modulate human longevity via the regulation of metabolic factors such as abdominal obesity and lipid profiles.
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Experimental gerontology · Dec 2011
Prophylactic lithium alleviates postoperative cognition impairment by phosphorylating hippocampal glycogen synthase kinase-3β (Ser9) in aged rats.
Postoperative cognition impairment is a perishing complication in elderly patients undergone surgeries. Lithium is widely used in psychiatric patients for its role in neuronal protection, whereas whether or not it could attenuate surgery-associated postoperative cognition dysfunction used prophylactically is not well defined. After approval by the Institutional Animal Care and Use Committee, 48 male Sprague-Dawley rats aged 18months old were randomly divided into three groups with 16 each: i, no surgeries and drugs were given; ii, surgical procedures were performed only without drug delivery; iii, prophylactic 2mM/kg lithium chloride was given intraperitoneally once a day for seven days before surgeries. ⋯ The MWM detection showed that both swimming latency and distance were considerably prolonged by the surgeries, but these changes could be markedly shortened by prophylactic lithium administration. Meanwhile, the changes in the hippocampal PI3K cascades and p-GSK-3β and IL-1β expression displayed corresponding changes that were parallel to the alterations of spatial memory, and inhibition of PI3K and GSK-3β suggested upstream PI3K activation leads to downstream change in p-GSK-3β and IL-1β. These results indicate, at least in part, that prophylactic lithium can alleviate surgery-associated impairment of the spatial memory in aged rats which is strongly associated with the reduced levels of hippocampal p-GSK-3β and IL-1β resulted from the activation of PI3K/AKT/mTORC2 pathway.
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Experimental gerontology · Nov 2011
Historical ArticleAtherosclerosis is an old disease: Summary of the Ruffer Centenary Symposium, The Paleocardiology of Ancient Egypt, a meeting report of the Horus Study team.
A symposium in January 2011 "The Paleocardiology of Ancient Egypt" reviewed old and new evidence for the presence of advanced atherosclerotic lesions in ancient Egyptian mummies. This symposium was dedicated as a Centenary for the pioneering report of Marc Ruffer in 1911 (Ruffer, 1911). ⋯ Comparisons were made with the Bolivian Tsimane, a 20th Century population living without access to modern medicine with short life expectancy. Further research is needed to develop an epidemiological context for estimating population level prevalence of vascular disease and its risk factors in ancient Egyptian societies.