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Related Articles [Mechanisms underlying dietary restriction-induced longevity]

Seikagaku. 2010 May;82(5):388-93

Authors: Honjoh S, Nishida E



PMID: 20560429 [PubMed - indexed for MEDLINE]



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Related Articles Sirtuin regulation in calorie restriction.

Biochim Biophys Acta. 2010 Aug;1804(8):1576-83

Authors: Qiu X, Brown KV, Moran Y, Chen D

The beneficial effects of calorie restriction diet in extending lifespan and preventing diseases have long been recognized. Recent genetic and molecular studies in model organisms began to uncover the molecular regulation of calorie restriction response, with the gene SIR2 playing an essential role. This article summarizes the latest development on how mammalian SIR2 homologs coordinately regulate the calorie restriction response.

PMID: 19782772 [PubMed - indexed for MEDLINE]



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Related Articles The role of Sirt1: at the crossroad between promotion of longevity and protection against Alzheimer's disease neuropathology.

Biochim Biophys Acta. 2010 Aug;1804(8):1690-4

Authors: Wang J, Fivecoat H, Ho L, Pan Y, Ling E, Pasinetti GM

Sirt1, a mammalian member of the sirtuin gene family, holds great potential for promoting longevity, preventing against disease and increasing cell survival. For example, studies suggest that the beneficial impact of caloric restriction in promoting longevity and cellular function may be mediated, in part, by Sirt1 through mechanisms involving PGC-1alpha, which plays important role in the regulation of cellular metabolism and inflammatory and antioxidant responses. Sirt1 may also interfere with mechanisms implicated in pathological disorders. We will present recent evidence indicating that Sirt1 may protect against Alzheimer's disease by interfering with the generation of beta-amyloid peptides. We will discuss Sirt1 as a potential novel target, in addition to the development of Sirt1 activators for the prevention and treatment of Alzheimer's disease.

PMID: 19945548 [PubMed - indexed for MEDLINE]



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Related Articles Inferring the functions of longevity genes with modular subnetwork biomarkers of Caenorhabditis elegans aging.

Genome Biol. 2010;11(2):R13

Authors: Fortney K, Kotlyar M, Jurisica I

A central goal of biogerontology is to identify robust gene-expression biomarkers of aging. Here we develop a method where the biomarkers are networks of genes selected based on age-dependent activity and a graph-theoretic property called modularity. Tested on Caenorhabditis elegans, our algorithm yields better biomarkers than previous methods - they are more conserved across studies and better predictors of age. We apply these modular biomarkers to assign novel aging-related functions to poorly characterized longevity genes.

PMID: 20128910 [PubMed - indexed for MEDLINE]



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Related Articles The use of FUdR can cause prolonged longevity in mutant nematodes.

Mech Ageing Dev. 2010 May;131(5):364-5

Authors: Aitlhadj L, Stürzenbaum SR

The nematode Caenorhabditis elegans is a popular model organism that is used to study longevity and aging. One drawback of nematode lifespan assays is the labour intensive separation of offspring from adults during the reproductive period. To circumvent this, the worm community frequently adds 5-fluoro-2'-deoxyuridine (FUdR), a drug that induces parental sterility, to the nematode culture. Here, we report that FUdR causes a significant artefactual increase in the longevity of tub-1 mutants which is not observed in wild-type nematodes. This suggests that the effect of FUdR is not neutral and the mechanism of action may result in misleading data, or indeed the misinterpretation of gerontogenes.

PMID: 20236608 [PubMed - indexed for MEDLINE]



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Related Articles A LINE-1 component to human aging: do LINE elements exact a longevity cost for evolutionary advantage?

Mech Ageing Dev. 2010 May;131(5):299-305

Authors: St Laurent G, Hammell N, McCaffrey TA

Advancing age remains the largest risk factor for devastating diseases, such as heart disease, stroke, and cancer. The mechanisms by which advancing age predisposes to disease are now beginning to unfold, due in part, to genetic and environmental manipulations of longevity in lower organisms. Converging lines of evidence suggest that DNA damage may be a final common pathway linking several proposed mechanisms of aging. The present review forwards a theory for an additional aging pathway that involves modes of inherent genetic instability. Long interspersed nuclear elements (LINEs) are endogenous non-LTR retrotransposons that compose about 20% of the human genome. The LINE-1 (L1) gene products, ORF1p and ORF2p, possess mRNA binding, endonuclease, and reverse transcriptase activity that enable retrotransposition. While principally active only during embryogenesis, L1 transcripts are detected in adult somatic cells under certain conditions. The present hypothesis proposes that L1s act as an 'endogenous clock', slowly eroding genomic integrity by competing with the organism's double-strand break repair mechanism. Thus, while L1s are an accepted mechanism of genetic variation fueling evolution, it is proposed that longevity is negatively impacted by somatic L1 activity. The theory predicts testable hypotheses about the relationship between L1 activity, DNA repair, healthy aging, and longevity.

PMID: 20346965 [PubMed - indexed for MEDLINE]



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Related Articles Enzyme characteristics of recombinant poly(ADP-ribose) polymerases-1 of rat and human origin mirror the correlation between cellular poly(ADP-ribosyl)ation capacity and species-specific life span.

Mech Ageing Dev. 2010 May;131(5):366-9

Authors: Beneke S, Scherr AL, Ponath V, Popp O, Bürkle A

Poly(ADP-ribosyl)ation is a posttranslational modification, which is involved in many cellular functions, including DNA repair and maintenance of genomic stability, and has also been implicated in cellular and organismal ageing. We have previously reported that maximum poly(ADP-ribosyl)ation capacity in mononuclear blood cells is correlated with mammalian life span. Here we show that the difference between a long-lived and a short-lived species tested (i.e. man and rat) is directly mirrored by the enzymatic parameters of recombinant poly(ADP-ribose) polymerase-1 (PARP-1), i.e. substrate affinity and reaction velocity. In addition, we have characterized two human PARP-1 alleles and assign their activity difference to their respective initial velocity and not substrate affinity.

PMID: 20399804 [PubMed - indexed for MEDLINE]



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Related Articles Growth and mortality of the fish Citharichthys xanthostigma (Pleuronectiformes: Paralichthyidae) off the Western coast of Baja California, México.

Rev Biol Trop. 2010 Jun;58(2):689-705

Authors: Martínez-Muñoz MA, Ortega-Salas AA

Longfin sanddab (Citharichthys xanthostigma) represents a very important fishery resource in Southern and Baja California but are not very well known. The purpose of this study is to provide information on the growth and mortality of longfin sanddab population in the Mexican Pacific Ocean at Baja California, México. Data on growth were obtained for longfin sanddab collected with otter trawls during six cruises off the Western coast of Baja California. A total of 1017 longfin sanddab were caught over the sampling period, and from 860 specimens, the male to female ratio was 1:1.8. The relationship between total weight (W) and standard length (SL) is described: W=0.00000743 SL(3.196) for females and W=0.00000764 SL(3.193) for males. Age groups were estimated from length frequency data, and von Bertalanffy annual growth parameters for all fish data combined were the following: L infinity=289.2 mm SL, k=0.20, t0=-0.73; for males, they were L infinity=265.9 mm SL, k=0.21, t0=-0.68, and for females, L infinity=293.6 mm SL, k=0.23, t0=-0.35. Longfin sanddab caught during this study reached a maximum age of 10 years, and at that age, males attained smaller sizes than females. The age groups had a total mortality (Z) rate of 0.82 year(-1), a fishing mortality (F) of 0.52 year(-1), and a natural mortality (M) of 0.3 year(-1). Although the longfin sanddab is not a target species of commercial fisheries, it suffers high mortality as part of the bycatch in the shrimp fishery.

PMID: 20527469 [PubMed - indexed for MEDLINE]



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Related Articles The impact of scheduled cage cleaning on older hens (Gallus gallus).

Lab Anim (NY). 2010 Jul;39(7):210-5

Authors: Anderson KE, Mozdziak PE, Petitte JN

Researchers are increasingly using the domestic hen (Gallus gallus) as an animal model for ovarian cancer. The authors analyzed mortality rates of two large flocks of older hens that were being used for ovarian adenocarcinoma studies. All hens were fed the same maintenance diets, though some hens in each flock received experimental chemopreventive treatments. Per the request of a collaborating institution, partway through the study, the authors started to remove the hens in one of the flocks for cage changing once every 4 weeks. After the authors began cleaning some of the hens' cages, the mortality rate in this flock increased significantly. Throughout the study, within each flock, hens in the treatment and control groups had similar mortality rates. These results suggest that regularly cleaning the cages of older hens may not promote better welfare or improve flock mortality.

PMID: 20567230 [PubMed - indexed for MEDLINE]



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Related Articles Making longevity in an aging society: linking ethical sensibility and Medicare spending.

Med Anthropol. 2009 Oct;28(4):317-25

Authors: Kaufman SR

An aging society, a growing array of life-extending medical interventions, Medicare policy, and an ethic of individual decision making together contribute to the deepening societal tension in the United States between controlling health care costs and enabling health consumer use of life-sustaining technologies. The activities that constitute longevity making, like so many other sociomedical practices, comprise a site for the governing of life and the emergence of new forms of ethical comportment and social participation. Those activities--including the necessity of treating risk, the difficulty of saying "no" to evidence-based interventions, and the responsibility of choosing among clinical options--also lie at the heart of debates about health care rationing and reform. Cardiac procedures, organ transplantation, and cancer treatments are three examples of medicine's success in extending life and are emblematic of the existential and societal quandaries that result. A perspective from medical anthropology shows the ways in which the making of life is linked to health care spending and the ongoing debates about age-based rationing.

PMID: 20182967 [PubMed - indexed for MEDLINE]



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