Abstract：
:We have developed a cell model for loss of differentiated gene expression in cellular aging. Over long periods in culture, bovine adrenocortical cells lose expression of a specialized gene, steroid 17 alpha-hydroxylase. The decline in expression of 17 alpha-hydroxylase in mass cultures and clones of bovine adrenocortical cells is the result of a phenotypic switching process which yields a mixture of cells that can express 17 alpha-hydroxylase after induction with cyclic AMP and cells that are incapable of expression of 17 alpha-hydroxylase. In the experimental portion of the work, bovine adrenocortical cells were grown in culture in colonies, stimulated with cyclic AMP to induce 17 alpha-hydroxylase, then fixed and hybridized in situ with labeled 17 alpha-hydroxylase cDNA. Separate images of Giemsa-stained cell colonies and of their hybridization patterns were digitized and combined as stylized representations of the colonies for comparison with those produced by a computer simulation. A program for the simulation of growth of colonies of bovine adrenocortical cells in senescence with phenotypic switching of 17 alpha-hydroxylase is presented. Comparison between simulated colonies and real colonies shows that the model accurately simulates colony growth and phenotypic switching. It suggests that the probability of phenotypic switching per cell generation is in the range of 0.03 to 0.06. The major variable among colonies is division probability, consistent with observations in this and other cell culture systems that clones differ widely in replicative potential. Thus, phenotypic switching of 17 alpha-hydroxylase in adrenocortical cells may be modelled using simple assumptions.
journal_name
Mech Ageing Devjournal_title
Mechanisms of ageing and developmentauthors
Hornsby PJ,Yang LQdoi
10.1016/0047-6374(91)90115-gsubject
Has Abstractpub_date
1991-04-01 00:00:00pages
1-12issue
1eissn
0047-6374issn
1872-6216pii
0047-6374(91)90115-Gjournal_volume
58pub_type
杂志文章abstract：:Although myocardial actomyosin ATPase specific activity determined at Ca2+ levels of 1 x 10(-3) to 1 x 10(-2) M is consistently higher in two-month old male Fischer rats than in twelve-month old individuals, this difference can be eliminated if the enzyme is assayed at lower calcium concentrations. This suggests that ...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(78)90040-4
更新日期：1978-12-01 00:00:00
abstract：:This study aimed to assess platelets as a possible model for screening the accumulation of mitochondrial DNA mutations, particularly during normal ageing. For this purpose we isolated platelets from young and old donors selected by lack of systemic and haematological diseases. We studied the accumulation of a particul...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(97)00181-4
更新日期：1998-04-01 00:00:00
abstract：:Ageing of WI-38 fibroblasts in culture was used as a model in order to investigate the evolution and the alteration of the key antioxidant enzyme glutathione peroxidase. The activity of glutathione peroxidase is influenced by the presence of selenium in the culture medium and we have also shown that the specific activ...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(91)90123-h
更新日期：1991-04-01 00:00:00
abstract：:Telomeres are supposed to play a role in cellular aging and might contribute to the genetic background of human aging and longevity. During the past few years telomere length has been measured in various human tissues. However, very little is known about the individual telomere loss in different tissues from the same ...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(00)00173-1
更新日期：2000-11-15 00:00:00
abstract：:BCL-2 functions as a death repressor molecule in an evolutionary conserved cell death pathway. Inactivation of bcl-2 in mice results in pleiotropic effects including postnatal growth retardation, massive apoptosis in lymphoid tissues, polycystic kidney disease (PKD) and shortened lifespan. To evaluate the influence of...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/j.mad.2006.02.009
更新日期：2006-07-01 00:00:00
abstract：:The influence of age on liver gene expression was investigated in two strains of H-2 congenic mice. In B10.RIII mice (H-2r), basal P1- and P3-450 RNA levels progressively decreased 65 and 95%, respectively, between 4 and 28 months of age (P less than or equal to 0.05). Polyaromatic hydrocarbon (PAH) induced P1- and P3...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(90)90038-h
更新日期：1990-03-31 00:00:00
abstract：:Susceptibility for Friend leukemia virus (FLV)-induced leukemogenesis was examined in the C3H/He (C3H)-->C57BL/6 (B6) radiation bone marrow chimeras of various age groups, and the effect of aging of host mice on the susceptibility was determined. The bone marrow chimera system provided the various age of FLV-resistant...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(00)00245-1
更新日期：2001-02-01 00:00:00
abstract：:In this investigation the effect of 4 months of 40% restriction of calories on defined markers of oxidative, glycoxidative or lipoxidative damage to heart mitochondrial proteins was studied. The protein markers assessed were N(epsilon)-(carboxyethyl)lysine (CEL), N(epsilon)-(carboxymethyl)lysine (CML), N(epsilon)-(mal...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(02)00076-3
更新日期：2002-09-01 00:00:00
abstract：:There is an alteration of the immune response in aging that leads to the increased incidence of infections, cancers and autoimmune disorders. The aim of the present study was to investigate whether there exists changes in signal transduction under the IL-2 receptor stimulation and the role of plasma membrane cholester...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(01)00274-3
更新日期：2001-09-15 00:00:00
abstract：:In most species, females live longer than males. An understanding of this female longevity advantage will likely uncover novel anti-aging therapeutic targets. Here we investigated the transcriptomic responses in the hypothalamus - a key organ for somatic aging control - to the introduction of a simple aging-related mo...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/j.mad.2019.111150
更新日期：2019-12-01 00:00:00
abstract：:This study attempts to elucidate the molecular mechanisms underlying the ageing-dependent cAMP profiles in human diploid fibroblasts stimulated by lysophosphatidic acid (LPA). In senescent cells, LPA-dependent Gialpha activation was reduced, with a consequent reduction in Gi-suppressed cAMP levels, without alterations...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/j.mad.2006.01.004
更新日期：2006-05-01 00:00:00
abstract：:We investigated the Coenzyme Q (CoQ) content of different mitochondrial fractions [free mitochondria (FM), synaptic heavy (HM) and light mitochondria (LM)] from three brain areas (cortex, striatum, hippocampus) of rats at different ages. In rats from 2 to 26 months of age, we observed only small differences in total C...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(94)01535-t
更新日期：1995-03-17 00:00:00
abstract：:Atypical bodies (ABs), related to aging, are described in the central nervous system of normal aged hamsters. Our study used ultrastructural microscopy and quantitative stereology analysis to study these structures in the hypothalamus and brain stem of 3, 6, 12, 18, 24 and 30 month-old hamsters. We found that these co...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(96)01755-1
更新日期：1996-09-09 00:00:00
abstract：:In this article we review the abnormalities in immune function which have been described in relation to ageing. It is suggested that thymic involution may not be the only underlying cause. Many similar changes can be induced by the endotoxins from the cell walls of Gram-negative bacteria. The colon is a large reposito...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章,评审
doi：10.1016/0047-6374(84)90091-5
更新日期：1984-08-01 00:00:00
abstract：:We have examined the effects of aging on guinea pig biliary motility both in vitro and in vivo. The first experiment compared contractile tension of gallbladder strips from young adult (6-12 months old) and 3-year-old guinea pigs in vitro. Contraction of gallbladder strips from the young guinea pigs was twice as force...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(88)90127-3
更新日期：1988-12-01 00:00:00
abstract：:The progression of many neurodegenerative diseases is assumed to be caused by misfolding of specific characteristic diseases related proteins, resulting in aggregation and fibril formation of these proteins. Protein misfolding associated age related diseases, although different in disease manifestations, share strikin...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章,评审
doi：10.1016/j.mad.2016.03.001
更新日期：2016-06-01 00:00:00
abstract：:The present work explores the application of information theoretical measures, such as entropy and normalized mutual information, for research of biomarkers of aging. The use of information theory affords unique methodological advantages for the study of aging processes, as it allows evaluating non-linear relations be...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/j.mad.2017.01.003
更新日期：2017-04-01 00:00:00
abstract：:Human cytomegalovirus (HCMV) establishes a highly prevalent life-long latent infection. Though generally subclinical, HCMV infection may have severe consequences during fetal development and in immunocompromised individuals. Based on epidemiological studies HCMV(+) serology has been associated with the development of ...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章,评审
doi：10.1016/j.mad.2016.06.010
更新日期：2016-09-01 00:00:00
abstract：:A morphometric investigation has been carried out on the synaptic junctions in the cerebellar glomeruli of young-adult rats chronically deprived of vitamin E for 10 months and control animals of the same age. The following parameters were evaluated: the average length of the synapses (L), the numerical (NV) as well as...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(84)90073-3
更新日期：1984-02-01 00:00:00
abstract：:Age related change of the human minor pectoral muscles was biochemically demonstrated. Myosin-ATPase activity was significantly decreased with age, and was activated with Tris. The degree of the activation by Tris was observed to be lower in old aged patients than in the young. Furthermore, at low concentration of CaC...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(85)80029-4
更新日期：1985-07-01 00:00:00
abstract：:Two types of age-related cell surface changes could be demonstrated in human diploid fibroblasts with the two methods of the lectin-mediated red blood cell (RBC) adsorption assay: the fibroblast coating method (in which RBCs are adsorbed to lectin-coated fibroblasts) and the RBC coating method (in which lectin-coated ...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(79)90004-6
更新日期：1979-11-01 00:00:00
abstract：:The present study examined the effect of a 40% reduction in caloric intake (CR) versus ad libitum (AL) feeding on retinal aging. CR- and AL-fed Brown Norway (BN) rats were obtained at 12, 24 and 30 months of age from the National Center for Toxicological Research (NCTR). Age-dependent declines in outer nuclear layer (...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/s0047-6374(00)00096-8
更新日期：2000-03-13 00:00:00
abstract：:The purpose of the present study was to investigate the effect of aging on silica-induced lung toxicity. In young animals silica induced a significant increase in bronchoalveolar lavage tumor necrosis factor-alpha (TNF), lactate dehydrogenase as well as in cell numbers, which correlate with increased collagen depositi...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/j.mad.2003.11.002
更新日期：2004-02-01 00:00:00
abstract：:Aging and HIV disease show certain immunological similarities. In both situations, control over viral infection is diminished, and there is an increase in certain types of cancer. The immune cell type responsible for controlling viral infections and cancer is the so-called CD8 or cytotoxic T cell. In elderly persons a...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章,评审
doi：10.1016/j.mad.2003.11.003
更新日期：2004-02-01 00:00:00
abstract：:Accumulation of oxidative DNA damage in the human brain has been implicated in etiologies of post-traumatic and age-associated declines in neuronal function. In neurons, because of high metabolic rates and prolonged life span, exposure to free radicals is intense and risk for accumulation of damaged DNA is amplified. ...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章,评审
doi：10.1016/j.mad.2008.02.001
更新日期：2008-07-01 00:00:00
abstract：:Age-related changes in intestinal glucose absorption were studied using everted intestinal sacs and brush border membrane vesicles prepared from male F344 rats. Glucose uptake by everted intestinal sacs was greatest in young (2-3-month-old) as compared with adult (12-14-month-old) and old (24-month-old) rats. The grea...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(87)90089-3
更新日期：1987-06-01 00:00:00
abstract：:Interfibrillar mitochondria (IFM) of the heart in aged Fischer 344 rats show a biochemical defect which might be reflected in their morphology. We examined by high resolution scanning electron microscopy over 5500 mitochondria to determine if a concomitant structural alteration existed. This methodology provides a mea...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/j.mad.2006.09.002
更新日期：2006-12-01 00:00:00
abstract：:In order to determine whether the function of alveolar macrophages (AM) is modulated by aging, we measured the TNF-alpha production, phagocytic function, and surface antigen expression of AM from young and old mice. When AM were primed by IFN-gamma (500 units/ml) and triggered by LPS (100 micrograms/ml), TNF-alpha pro...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(93)90024-l
更新日期：1993-07-01 00:00:00
abstract：:Menopause is characterized by the depletion of estrogen that has been proposed to cause oxidative stress. Circadian rhythm is an internal biological clock that controls physiological processes. It was analyzed the gene expression in peripheral blood mononuclear cells and the lipids and glucose levels in plasma of a su...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章,随机对照试验
doi：10.1016/j.mad.2017.04.002
更新日期：2017-06-01 00:00:00
abstract：:To investigate age-related changes in gene expression in WI-38 cells, we isolated RNA from young and senescent, quiescent cultures and made subtracted cDNA libraries. Density-arrested cells were incubated in serum-free MCDB-104 for 3 days. RNA was then isolated and subtracted cDNA libraries were made in the phagemid v...
journal_title：Mechanisms of ageing and development
pub_type： 杂志文章
doi：10.1016/0047-6374(92)90039-g
更新日期：1992-09-01 00:00:00
