Abstract:
:Age-related bone loss is thought to be due to impaired osteoblast functions. Insulin-like growth factors (IGFs) have been shown to be important stimulators of bone formation and osteoblast activities in vitro and in vivo. We tested the hypothesis that in vitro osteoblast senescence is associated with changes in components of the IGF-system including IGF-I, IGF-II, IGF-binding proteins (IGFBPs) and IGFBP-specific proteases. We employed a human diploid osteoblast cell line obtained from trabecular bone explants and that exhibit typical characteristics of in vitro senescence during serial subculturing. Using a non-competitive reverse-transcriptase polymerase-chain reaction (RT-PCR) assay, we found that the constitutive level of IGF-I mRNA decreased progressively to 49.9 +/- 4.9% in old osteoblasts as compared to the levels found in the young cells. No age-related change was found in IGF-II steady-state mRNA levels. Changes in IGFBPs gene expression and protein production were assessed using Northern blot analysis and Western ligand blotting (WLB), respectively. IGFBP-3 mRNA levels decreased to 30% and protein production to 16% in aged osteoblasts as compared to levels found in young cells. We also found age-related decreases in mRNA levels of both IGFBP-4 and IGFBP-5 to 70% and 60% in aged osteoblasts, respectively, compared to young cells. While IGFBP-5 protein was not detected by WLB, IGFBP-4 protein production showed a biphasic change with 50% decrease in middle-aged cells and a subsequent increase in aged osteoblasts to levels similar to those in young osteoblasts. We found an age-related increase in the immunoreactive levels of IGFBP-4 protease, however, no detectable IGFBP-4 or IGFBP-3 protease activities in conditioned media from osteoblast cultures were observed. Our findings demonstrate that osteoblast aging is associated with impaired production of the stimulatory components of the IGF-system, that may be a mechanism contributing to age-related decline in osteoblast functions.
journal_name
Exp Gerontoljournal_title
Experimental gerontologyauthors
Kveiborg M,Flyvbjerg A,Rattan SI,Kassem Mdoi
10.1016/s0531-5565(00)00125-xkeywords:
subject
Has Abstractpub_date
2000-10-01 00:00:00pages
1061-74issue
8eissn
0531-5565issn
1873-6815pii
S0531-5565(00)00125-Xjournal_volume
35pub_type
杂志文章abstract::Cellular aging plays a role in longevity and senescence, and has been implicated in medical and psychiatric conditions, including heart disease, cancer, major depression and posttraumatic stress disorder. Telomere shortening and mitochondrial dysfunction are thought to be central to the cellular aging process. The pre...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2015.04.002
更新日期:2015-06-01 00:00:00
abstract::Diet is the most variable aspect of life history, as most individuals have a large diversity of food choices, varying in the type and amount that they ingest. In the short-term, diet can affect metabolism and energy levels. However, in the long run, the net deficiency or excess of calories from diet can influence the ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2016.02.012
更新日期:2016-12-15 00:00:00
abstract::In aging tissues the oxidative stress increases due to decreased activity of antioxidant enzymes and proteolysis increases due to decreased activity of aminotransferases, which can be modified by hormonal replacement therapy (HRT). The aim of the present study was to determine the effect of HRT on the activities of an...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2005.01.004
更新日期:2005-04-01 00:00:00
abstract::This study was designed to investigate whether the relationship of fiber size and force is maintained with aging and inactivity. We hypothesized that fiber size and fiber force-generating capacity would decrease in parallel, thus resulting in no change in specific force with either age or inactivity. Thirty male Fisch...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2004.12.002
更新日期:2005-03-01 00:00:00
abstract:OBJECTIVES:1) To determine if there was a practice effect associated with walk tests performed by frail older adults with and without dementia, 2) to examine the role of systematic cueing in the walk tests for those with dementia, and 3) to make recommendations to testing protocols of the walk tests for frail older adu...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2019.110648
更新日期:2019-09-01 00:00:00
abstract::Alterations in the hypothalamic-pituitary-gonadal axis in females determine the transition from regular to irregular reproductive cycles, with loss of fertility. Stimulation of noradrenergic neurons of the anteroventral periventricular neurons (AVPV) is essential for regular reproductive cycles. Therefore, we examined...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2015.10.003
更新日期:2015-12-01 00:00:00
abstract::Vascular endothelial growth factor (VEGF) has been identified as a potential treatment for effectively improving cognitive function in several neuropathological conditions. However, the underlying mechanism and the relevant downstream protective pathways that are activated in neurons by VEGF remain elusive, especially...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2017.12.010
更新日期:2018-02-01 00:00:00
abstract::The effect of deleting both catalase genes and of increased oxygen as well as paraquat (a pro-oxidant) on the replicative life span of yeast mother cells has been investigated to test the so-called oxygen theory of aging. This is well established in higher organisms, but has not been extensively tested in the unicellu...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(99)00087-x
更新日期:2000-02-01 00:00:00
abstract::Male life history and resource allocation is not frequently studied in aging and life span research. Here, we verify that males of long-lived fruit-feeding butterfly species have reduced longevity on restricted diets [Beck, J., 2007. The importance of amino acids in the adult diet of male tropical rainforest butterfli...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2009.06.008
更新日期:2009-09-01 00:00:00
abstract::Rodent gerontology experiments should be carefully designed and correctly analyzed so as to provide the maximum amount of information for the minimum amount of work. There are five criteria for a "good" experimental design. These are applicable both to in vivo and in vitro experiments: (1) The experiment should be unb...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(96)00032-0
更新日期:1997-01-01 00:00:00
abstract::Studying renal function in subjects with a familial propensity for longevity may provide insight in (un)known mechanisms that determine the age-related decline in renal function of normal subjects. In the Leiden Longevity Study, middle-aged offspring of non-agenarian siblings and their partners as environmentally matc...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2013.12.012
更新日期:2014-03-01 00:00:00
abstract::Rats of Albino Oxford (AO) strain in our animal facility exhibit a longer average healthy life span than rats of Dark Agouit (DA) strain. Since chronic activation of macrophages contributes to chronic low level inflammation common in older age, elucidation of the changes in middle-aged rats could be useful in preventi...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2016.10.005
更新日期:2016-12-01 00:00:00
abstract::A number of recent studies of aging in Drosophila, mice and dogs have shown an association between reduced body size and increased lifespan. It is unclear (a) whether such an association is a general feature of animal species; and (b) whether the association reflects an effect of body size on aging, or pleiotropic eff...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(02)00147-x
更新日期:2003-01-01 00:00:00
abstract::Histological surveys of the hearts of guppies Poecilia reticulatus throughout their lifespan showed no aging changes until the fish were three years old. In younger fishes the hearts were healthy, even in three individuals with "wasting" disease, where there was considerable loss of muscle throughout the body. There w...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(84)90048-2
更新日期:1984-01-01 00:00:00
abstract:OBJECTIVES:To date studies evaluating the relation between circulating aldosterone levels and mortality in elderly female individuals are lacking. We therefore aimed to assess the relationship between circulating aldosterone levels and mortality in a population-based cohort study of female nursing home residents. METH...
journal_title:Experimental gerontology
pub_type: 杂志文章,多中心研究
doi:10.1016/j.exger.2013.01.004
更新日期:2013-03-01 00:00:00
abstract::We suggest that the processes that protect the turtle brain against anoxia and subsequent reoxygenation might also contribute to turtle longevity since many of them are linked to age related neurodegeneration. In the turtle the mechanisms for conserving ion channel function are particularly robust. The anoxic turtle b...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(03)00111-6
更新日期:2003-07-01 00:00:00
abstract::Mitochondria isolated from the livers of old rats (26-30 months) were found to incorporate 41% less leucine into mitochondrial proteins as compared to those from young rats (2-3 months). The initial rates of incorporation of label were 145 cpm/mg/min for the "old" animals, and 320 cpm/mg/min for the young animal. No d...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(82)80004-1
更新日期:1982-01-01 00:00:00
abstract::Senescence accelerated mice (SAM) are susceptible to developing vascular dysfunction and remodeling. Food intake and type of diet have also been identified as determining factors in vascular remodeling. However, the interplay between senescence and diet in vascular remodeling is largely unknown. We aimed to analyze st...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2014.03.004
更新日期:2014-07-01 00:00:00
abstract::The observation that long-lived and relatively healthy animals can be obtained by simple genetic manipulation prompts the search for chemical compounds that have similar effects. Since aging is the most important risk factor for many socially and economically important diseases, the discovery of a wide range of chemic...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2008.08.049
更新日期:2008-10-01 00:00:00
abstract::Mouse models have been widely used in the research of human diseases. Aging, just as cancer, is influenced by the interaction of various genetic and environmental factors. Currently, aging could be induced by many mechanism, including telomere dysfunction, oxidase stress, DNA damage and epigenetic changes. Many of the...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/j.exger.2019.03.002
更新日期:2019-06-01 00:00:00
abstract::The purpose of this study was to examine the relative contributions of changes in muscle quality and body composition to changes in lower-extremity physical function (LEPF) following a 6-month exercise and weight loss intervention in overweight and obese older women. Thirty-eight overweight and obese (BMI = 30.0 ± 4.4...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2018.04.011
更新日期:2018-07-15 00:00:00
abstract::As the analysis of apoptosis is of interest in many basic and clinically oriented investigations, we intend to give a brief overview on the recently most-used methods for detection of apoptotic cells, including the study of morphology, analysis of DNA degradation, DNA end-labeling techniques, flow cytometric analysis,...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(98)00031-x
更新日期:1998-09-01 00:00:00
abstract::Lipid hydroperoxides are formed in vivo through free radical pathways from the action of reactive oxygen species on polyunsaturated fatty acids. They are also formed as specific products of lipoxygenases and cyclooxygenases. Homolytic decomposition of lipid hydroperoxides to the alpha,beta-unsaturated aldehyde genotox...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(01)00133-4
更新日期:2001-09-01 00:00:00
abstract:BACKGROUND:Hyaline articular cartilage, which protects the bones of diarthrodial joints from forces associated with load bearing, frictions, and impacts has very limited capacities for self-repair. Over the years, the trend of treatments has shifted to regenerations and researchers have been on the quest for a lasting ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2018.01.020
更新日期:2018-04-01 00:00:00
abstract:INTRODUCTION:Aging leads to poorer neuromuscular control that may impact mobility. However, the specific decades when these changes occur, and whether these time-based changes are sex-specific, are unclear. METHODS:Adults aged 20-82 years (N = 93, 51 females) walked six gait trials at their preferred speed over a 10-m...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2018.05.005
更新日期:2018-09-01 00:00:00
abstract:INTRODUCTION:The ageing process can be influenced by different dietary patterns and dietary factors. AIM:To analyse the association of dietary factors, which include the Mediterranean diet adherence, the compliance with the "Sociedad Española de Nutrición Comunitaria" food portion recommendations, and the intake of di...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2019.01.019
更新日期:2019-05-01 00:00:00
abstract::Ageing is highly complex, involving multiple mechanisms at different levels. Nevertheless, recent evidence suggests that several of the most important mechanisms are linked via endogenous stress-induced DNA damage caused by reactive oxygen species (ROS). Understanding how such damage contributes to age-related changes...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(01)00111-5
更新日期:2001-07-01 00:00:00
abstract::Reactive oxygen species (ROS) play important roles in cellular senescence and organismic aging. Furthermore, they have been implicated in some of the adverse effects of chronic stress due to elevated peripheral levels of catecholamines. Here, we applied three different techniques to individually compare the systemic a...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2007.08.003
更新日期:2007-11-01 00:00:00
abstract::Initial velocity of GABA uptake in hypothalamic synaptosomes has been measured in aged animals as a function of both sodium and GABA concentration and compared to previous studies in young animals. The data give good fit to the model found previously to give minimal best fit to control data. Thus it appears that aging...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(83)90005-0
更新日期:1983-01-01 00:00:00
abstract::Age-related changes of immune functions have been extensively investigated in both humans and animal models; nevertheless, the literature on potential alterations of dendritic cells, potent antigen presenting cells responsible for initiating immune responses, with aging is very scarce. We studied the immuno-phenotype ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(99)00089-3
更新日期:2000-03-01 00:00:00