Interfering with longevity

Several recent studies have highlighted how RNA interference has advanced aging-related research in Caenorhabditis elegans. Two new genome-wide RNAi-based screens together identified more than 100 new candidate longevity genes. RNAi has also greatly facilitated the functional validation of several large-scale gene expression profiling studies. Furthermore, RNAi is flexible and can be administered at different times throughout life; this feature has been exploited to analyze the temporal requirement of genes in life-span determination.     

Vital connections

Scientists are currently exploring the structure and behavior of complex biological systems, which consist of networks of interacting entities. A recent paper in Proceedings of the Royal Society of London Series B Biological Sciences describes the distinctive characteristics of aging-related proteins in the yeast protein-protein interaction network. In this Perspective, I discuss the implications of these findings for longevity research.     

The graying of "sexual health": a critical research agenda

This paper critically interrogates the concept of sexual health as it has evolved in relation to older adults. I draw on social and cultural studies of aging, feminist studies, and science and technology studies to outline a research agenda which treats sexual health as a point of articulation for a range of technologies and processes which shape mid- and late-life sexualities. Such an agenda may be able to more fully interrogate the sites and processes by which sexualities are being shaped, the forms of sexual agency on offer to older people, and the contemporary reconstruction of sexual life courses.     

Introduction: Human Longevity,Utopia, and Solidarity

Biomedical and geriatric technologies are having major impacts on the development and management of human longevity. Our contention in this special issue is that longevity should be considered as a point of departure for new forms of politics in which social sciences, in particular sociology and politics, can play an important role. In this introduction, we argue that emerging consumer markets in biomedicine are incrementally redefining the relationship between old age and society. Techno‐economic transformations are creating new sites of vulnerability that are masked by medical utopias of good health and “living forever.” In this context, it is unlikely that such technologies will be able to overcome inequalities in distribution and may well exacerbate various forms of injustice. By drawing on notions of institutional precariousness and scarcity, we conclude that to maintain any degree of social solidarity, increasing longevity will force the emergence of a “sociology of limits.”     

Is Akt the mastermind behind age-related heart disease?

Over the past several years, the insulin/insulin-like growth factor (IGF) signaling pathway has become a central figure in the study of organismal aging. Mutations in components of this pathway have led to enhanced longevity in several organisms, but it is still not clear whether and how this pathway contributes to human aging and aging-related diseases. In a new study, Miyauchi and colleagues propose that Akt, a member of the phosphatidylinositol 3-kinase family and a downstream component of the insulin/IGF pathway, plays a central role in the life span of endothelial cells. These findings implicate the insulin/IGF pathway in the development and progression of cardiovascular disease.     

Ceramide, stress, and a "LAG" in aging

Recent studies have implicated the longevity assurance gene LAG1 in ceramide synthesis. In light of a role for ceramide in yeast and mammalian stress responses and mammalian cellular senescence, important connections are emerging between ceramide and organismal aging. In this Perspective, we examine the evidence for these connections in yeast, Drosophila, and mammals, and speculate on their implications.     

The molecular basis of age-related kidney disease

Renal disease affects 11% of people in the United States over the age of 65, not including those with diabetes or hypertension. Although glomerular disease is the most common underlying etiology of age-related renal dysfunction, the cause of glomerular disease and whether it is the only contributor to renal failure are not known. Our studies in female mice show that renal disease in the postmenopausal period is associated with progressive glomerular enlargement and scarring, as well as abnormal renal function. To study the underlying causes of aging-related glomerular disease, we isolated and characterized glomerular smooth muscle (mesangial) cells from female mice of various ages. We found that the cells from older mice exhibit a variety of phenotypic changes, including increased concentrations of p27, a protein that serves to inhibit progression from the G1 to the S phase of the cell cycle. Because the bone marrow (BM) contains mesangial cell progenitors that can transfer the donor glomerular phenotype (normal or diseased) to recipients, we exchanged BM between postmenopausal and premenopausal mice and found that aging-related glomerular enlargement and scarring are transferred to young recipient glomeruli. In addition, BM from normal, young donors led to the regression of aging-related glomerular disease in postmenopausal recipients; namely, both glomerular enlargement and scarring were reduced. Thus, aging-related glomerular disease is an entity distinct from all other causes of renal disease, is characterized by phenotypic changes in mesangial cell progenitors, and is reversible when the phenotype of the progenitors is returned to normal.     

Microarrays as a tool to investigate the biology of aging: a retrospective and a look to the future

The use of microarrays as a tool to investigate fundamental biological questions has become ubiquitous over the past several years. Microarrays are becoming as common as the polymerase chain reaction or any of the other tools in the molecular biologist's armory. Unlike experiments involving other tools, however, the design and analysis of microarray experiments present some unique problems to molecular biologists, problems with which statisticians have long been familiar. In this overview of microarrays and aging-related research, we will review selected highlights of microarray studies that have been carried out to study aging to date, as well as discuss some of the potential problems that routinely arise during these types of experiments, especially in the context of aging.     

Planning for the Residential Needs of Lesbian,Gay, Bisexual,and Transgender Older Adults

Lesbian, gay, bisexual, and transgender (LGBT) older adults experience housing-related barriers. Previous research has described residential challenges experienced by this population, but few studies have examined implementation of housing solutions. This exploratory study conducted 7 semistructured phone interviews with program directors and/or development managers from initiatives offering residential services to LGBT older adults. Qualitative analysis identified themes that characterize the implementation of housing solutions. Study results suggest that future residential solutions for LGBT older adults should consider housing in relation to other aging-related barriers and frame solutions that promote collaboration among community actors (e.g., residential and service providers).     

Analogical Problems with Digital Data

Current initiatives of digitally archiving ethnographic and linguistic data promise considerable advantages with regard to longevity and accessibility. This article discusses these ‘digital promises’ in the context of projects funded by recent research programs on endangered languages and cultures. It is argued that far from being merely a new technological tool for preserving data, digital archiving has considerable impact on the ways in which knowledge and research is organised and on the relationship between the participants in the research process. The new technological means change the structure of ethnographic data collections while highlighting a number of questions of data access and property rights that are analogous to earlier, and largely still unresolved, debates about the ethics of research and about data access and ownership.     

Life in the fast lane? Towards a sociology of technology and time

Assumptions about the pace of life speeding up abound in contemporary social theory. While many factors are contributing to this phenomenon, information and communication technologies are seen as the main drivers. This article considers the way social theorists analyse the concepts of time and speed and then examines how these claims might be assessed in the light of empirical research. Such research shows that time compression has multiple dimensions, and that the effect of digital devices like the mobile phone is not simply one of acceleration. In particular, I suggest that the social studies of technology offers a richer analysis of the reciprocal relationship between technological innovation and changing time practices. My argument is that while the hitherto neglected temporal dimension in sociological theory is now being addressed, there is an urgent need for increased dialogue to connect social theory with detailed empirical studies. Without this, we will continue to have difficulty distinguishing social science from science fiction.     

The benefits of information communication technology use by the homeless: a narrative synthesis review

Recent studies have suggested that technologies are becoming an increasingly ubiquitous element in the lives of individuals experiencing homelessness. With both Canadian and US researchers reporting staggering levels of homelessness on both sides of the border, an understanding and synthesis of the current literature exploring how technologies are being utilized by homeless individuals and how it may impact their well-being is of relevance to policy makers and social service organizations. The study explored and synthesized literature to examine the ways in which individuals experiencing homelessness utilize information and communication technologies (ICTs), and how the use of ICTs influences the health and social outcomes of individuals experiencing homelessness. The study examined 16 peer reviewed articles using a narrative synthesis systematic review, following three elements of the narrative synthesis approach: preliminary synthesis of findings; exploration of relationships between studies; and assessment of the robustness of the synthesis. In relation to what ICTs are used for by homeless individuals, three major themes emerged: social connectedness, identity management, and instrumental purposes. Furthermore, there was some tentative evidence about a positive relationship between ICT use among individuals experiencing homelessness and health outcomes. The paper discussed limitations, future areas of research, as well as some policy directions.     

Frailty--the search for underlying causes

Research into the biological basis of frailty has been difficult to accomplish because of a lack of standardized definitions, disease and disability confounders, and complex multifactorial etiology. Multiple physiological systems are likely to be involved, including the skeletal muscle, endocrine, and immune/inflammation systems. Physiological characterization of frail older adults might provide etiologic clues. Translational research programs that connect mechanisms related to aging, such as oxidative damage and telomere shortening, to clinical aging-related syndromes will be necessary to further this critical area of geriatric research.     

Measuring and understanding trade in service tasks

The revolution in information and communications technologies has put service tasks with strong tradability characteristics at high risk of being offshored. This article reviews studies proposing indicators of service tradability, exploring the labour market implications of service offshoring and developing theories to rationalize the facts. It suggests that both skill intensity and tradability are determinants of wage and employment effects. Nonetheless, the lack of widely accepted definitions of tradability, the absence of high‐quality data on service trade flows and the difficulty of measuring import competition at higher disaggregation levels pose difficulties in achieving further progress, pointing to areas for future research.     

Instruments for research on transition: Applied methods and approaches for exploring the transition of young care leavers to adulthood

Young people who have been in care show relatively poor outcomes in comparison to young people who have not been in care, and run a high risk of social exclusion. Therefore, the transition to adulthood of young people leaving care is an important topic for research. However, there is still little knowledge about the different research approaches and research instruments that are being used in studying this topic. The aim of the present study is to review the approaches and instruments that are used in empirical studies that focus on young care leavers' transitions to adulthood. The results show that the studies apply a diversity of topics and instruments, but that there is also considerable overlap. To make better comparisons on the transition from out-of-home care to adulthood between different countries, a common research framework and one or more research instruments should be developed that can assess this transition and the situation of young care leavers in diverse social contexts.     

Murine models of life span extension

Mice are excellent experimental models for genetic research and are being used to investigate the genetic component of organismal aging. Several mutant mice are known to possess defects in the growth hormone/insulin-like growth factor 1 (GH/IGF-1) neurohormonal pathway and exhibit dwarfism together with extended life span. Their phenotypes resemble those of mice subjected to caloric restriction. Targeted mutations that affect components of this pathway, including the GH receptor, p66Shc, and the IGF-1 receptor (IGF-1R), also extend life span; mutations that affect IGF-1R or downstream components of the pathway decouple longevity effects from dwarfism. These effects on life span may result from an increased capacity to resist oxidative damage.     

GEHA--the pan-European "Genetics of Healthy Aging" project

The pan-European "Genetics of Healthy Aging" (GEHA) consortium is undertaking a large study of long-lived individuals, which officially began on 22 May 2004. The consortium aims to identify genes that promote longevity and good health during the process of aging. The project will involve scientists working in multiple disciplines and using a variety of techniques.     

From bedside to bench: research agenda for frailty

The American Geriatrics Society sponsored a working conference in January 2004, funded by the National Institute on Aging, to establish the state of the art in frailty research and to set a research agenda for the future. The invited participants included senior basic biologists, epidemiologists, geneticists, and clinical investigators who study aging-related issues. This article summarizes the central theoretical observations on frailty and research needs and opportunities presented and discussed at this conference, and lays out an agenda for future research on frailty.     

Allelic variation and human longevity

Human longevity is a complex phenotype with a strong genetic contribution. The search for allelic variation that impacts on longevity often involves population-based association studies of long-lived individuals (centenarians and nonagenarians) and younger controls. A major methodological problem with this approach is that the cases and controls in these experiments are often born several generations apart. The inherent absence of "age matching" can lead to serious misinterpretations. For example, allele frequency differences between long-lived individuals and younger controls may not reflect an effect on longevity but rather a change in population structure over time or different gene-environment interactions across generations.     

Exposure to "low-level" aggression in school: associations with aggressive behavior, future expectations, and perceived safety

Examined associations with witnessing and being victimized by "low-level" aggressive acts (e.g., pushing, gossip) and three indicators of psychosocial functioning in a sample of 771 elementary school students from one urban and one suburban school district. Results indicated that exposure to low-level aggression appears to relate to psychosocial functioning in ways similar to more severe forms of aggression. Students who were exposed to higher levels of both witnessing and victimization by low-level aggression reported the highest levels of engagement in aggression, the lowest levels of positive expectations for the future, and the lowest levels of perceived safety. Findings are discussed in the context of research on exposure to aggression in general, with suggestions offered for future studies. Implications of the findings for school-based intervention programs are raised.