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Martin M, el Nabout R, Lafuma C, Crechet F, Remy J. Fibronectin and collagen gene expression during in vitro ageing of pig skin fibroblasts. Exp Cell Res 1990; 191:8-13. [PMID: 2226653 DOI: 10.1016/0014-4827(90)90028-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The fibronectin, collagen type I, and collagen type III genes code for three major proteins of the cell matrix. The age-related alterations in their expression were measured during the in vitro lifespan of pig skin fibroblasts. We observed changes in the transcription rate of these specific genes during ageing. The levels of fibronectin and type III collagen mRNA rose markedly during the senescence phase. The level of collagen type I mRNA decreased during cell ageing, while that of beta-actin did not change. As regards proteins, we observed a sharp increase in the secreted noncollagenous proteins and in the total proteins of the cell layer during senescence. On the contrary, the secretion of the collagenous proteins decreased during senescence. Moreover, most of the newly synthesized molecules of collagen were immediately degraded in the cells, before their extracellular secretion. The terminal phenotype of pig senescent cells was therefore characterized by overexpression of fibronectin and type III collagen genes and reduced expression of the type I collagen gene. Surprisingly, for fibronectin and type III collagen, that terminal phenotype resembled the one normally found in the fibroblasts during the processes of tissue repair, cicatrization, and development.
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Affiliation(s)
- M Martin
- Laboratoire de Radiobiologie Appliquée-Commissariat à l'Energie Atomique, IPSN-DPS, Centre de Saclay, Gif Sur Yvette, France
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Kihara F, Tsuji Y, Miura M, Ishibashi S, Ide T. Events blocked in prereplicative phase in senescent human diploid cells, TIG-1, following serum stimulation. Mech Ageing Dev 1986; 37:103-17. [PMID: 2434812 DOI: 10.1016/0047-6374(86)90069-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
When senescent human diploid cells, TIG-1, were stimulated with serum at the end of their proliferative life span, such biochemical events as uptakes of 2-deoxyglucose and uridine, and expression of c-myc, were enhanced. However, RNA synthesis, polyamine accumulation, thymidine uptake and DNA synthesis were not enhanced at all. Protein synthesis increased only moderately as compared with that observed in younger cells. These results indicated that the events in prereplicative phase known to be independent on protein synthesis are induced in senescent cells after the stimulation with serum, whereas those required protein synthesis failed to increase to the same extent as seen in young cells.
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3
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Chen KY, Chang ZF. Age dependency of the metabolic conversion of polyamines into amino acids in IMR-90 human embryonic lung diploid fibroblasts. J Cell Physiol 1986; 128:27-32. [PMID: 3087998 DOI: 10.1002/jcp.1041280106] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
When radioactive polyamines (putrescine or spermidine) were incubated with mammalian cells in tissue culture, the radioactivity was incorporated into cellular proteins via two different metabolic pathways; one is metabolic labeling of an 18,000-dalton protein via hypusine formation, and the other is general protein synthesis employing radioactive amino acids derived from biodegradation of polyamines via GABA shunt and Krebs cycle. Aminoguanidine, a potent inhibitor of diamine oxidase, blocked the metabolic conversion of polyamines to amino acids but had no effect on the metabolic labeling of the 18,000-dalton protein. We have investigated these two polyamine-associated biochemical events in IMR-90 human diploid fibroblasts as a function of their population doubling level (PDL). We found that (1) the metabolic labeling of the 18,000-dalton protein was about two-fold greater in young cells (PDL = 22) than that in old cells (PDL = 48), and (2) the metabolic labeling of other cellular proteins, employing amino acids derived from putrescine via polyamine catabolic pathway, was more than six-fold greater in the old cells (PDL = 48) than in the young cells (PDL = 22). Since the rate of protein synthesis was about 1.4-fold higher in the young cells as compared to the old cells, our data indicated that the activity of catabolic conversion of putrescine (or spermidine) to amino acids in old IMR-90 cells was about eight-fold greater than that in young cells. This remarkable increase of polyamine catabolism and the slight decrease of metabolic labeling of the 18,000-dalton protein were also observed in cell strains derived from patients with premature aging disease.
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4
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Minkowitz S, Conklin DP, Kaplan P. Total LD and isozyme variations during in vitro fibroblast aging with a discussion of its theoretical implication. Mech Ageing Dev 1985; 31:163-9. [PMID: 4058067 DOI: 10.1016/s0047-6374(85)80027-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Dermal fibroblast cultures were obtained from 18 patients. Total lactic dehydrogenase (LD) and LD isozymes were determined after each population doubling (PD). The lactic dehydrogenase was assayed by the method of Wacker, Ulmer and Vallee. The isozymes were analyzed by gel electrophoresis. Some investigators have reported conflicting results as to the quantity of LD produced during in vitro aging. These researchers sampled a small number of PDs. We found that the total LD varied with each PD. A distinct isozyme pattern has been described for adult, fetal and neoplastic fibroblasts. We have found all three patterns occurring during the in vitro aging of our normal diploid fibroblasts. In spite of our asynchronous population of cells the LD and its isozymes continually fluctuate. An asynchronous population of cells would be expected to produce a dampening of the total LD. In order to explain this finding we speculate a synchrony is established in a "gated" entrance from subcycle Gq into the S stage or from G1 and G0 into the S stage. In order to evaluate, accurately, changes occurring during in vitro aging it is imperative to assay each PD.
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5
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Doughty MJ, Davis MH, Gruenstein E. Reversible change in the fibroblast lysosomal enzyme dipeptidyl aminopeptidase-1 (cathepsin C) related to the commercial source of fetal bovine serum in the culture medium. IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY : JOURNAL OF THE TISSUE CULTURE ASSOCIATION 1985; 21:340-6. [PMID: 3894318 DOI: 10.1007/bf02691582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The commercial source of fetal bovine serum used to supplement the growth medium of human skin fibroblasts alters the activity of the lysosomal enzyme dipeptidyl aminopeptidase-1 (DAP-1). Cells grown with one serum were found to have a threefold higher level of DAP-1 than those grown with serum from another source (P less than 0.001). The effect on DAP-1 activity was specific inasmuch as no differences were found in the activities of a variety of other lysosomal and nonlysosomal hydrolases: DAP-II, DAP-III, DAP-IV, beta-glucosidase, beta-glucuronidase, and N-acetyl-beta-galactosaminidase. The effect is reversible and is observed over a wide range of cell population doublings. Cell growth kinetics were not significantly different with the different sera.
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6
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Belyaeva ID, Ivleva TS, Vidershain GY. Lysosomal glycosidase activity in human fibroblasts in culture. Bull Exp Biol Med 1984. [DOI: 10.1007/bf00800014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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7
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Sambuy Y, Bittles AH. The effects of in vitro ageing on the exopeptidases of human diploid fibroblasts. Mech Ageing Dev 1984; 26:13-22. [PMID: 6379325 DOI: 10.1016/0047-6374(84)90161-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Six exopeptidases present in human diploid fibroblasts were identified by separation on polyacrylamide gel electrophoresis and their activity profiles against 17 dipeptides, two tripeptides and L-leucine-p-nitroanilide determined. No differences in relative activity or in the electrophoretic patterns of any of the six exopeptidases were detected with ageing. Aminoacylarylamidase activity assayed spectrophotometrically showed significantly increased activity in the middle age-group cells as opposed to the enzyme isolated from young and old cells. Heat-inactivation studies using the same substrate suggested the possibility of an increased proportion of heat-labile enzyme in the old cells but interpretation of the data was difficult because of the complex nature of the inactivation curves obtained. Overall, the results tended to refute the hypothesis that age-related changes in the free amino acid pool of human diploid fibroblasts were associated with significant alterations in the activities of cellular exopeptidases.
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8
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Sambuy Y, Bittles AH. The effects of in vitro ageing on the composition of the intracellular free amino acid pool of human diploid fibroblasts. Mech Ageing Dev 1982; 20:279-87. [PMID: 6926091 DOI: 10.1016/0047-6374(82)90096-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The composition of the free amino acid pool of the human diploid fibroblast cell line, BCL-D1, was analysed by automated ion-exchange chromatography throughout the life-span of the culture. Significant age-related changes, independent of growth effects, were found with six essential amino acids: a decrease in tyrosine, phenylalanine, leucine, isoleucine and valine, and an increase in methionine. The nature of the changes were suggestive of a decline in the operation of the L-system of amino acid transport with in vitro age. However, it is also possible that age-related changes in the proportions of tRNA iso-acceptors and/or the availability and accuracy of tRNA synthetases were involved.
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9
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Ethier MF, Hickler RB, Saunders RH. Cholesterol and cholesteryl ester concentration in different size classes of cultured human fibroblasts: effect of in vitro aging. Mech Ageing Dev 1982; 20:165-74. [PMID: 7176708 DOI: 10.1016/0047-6374(82)90067-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Early and late passage WI-38 fibroblasts were fractionated on the basis of cell size by gravity sedimentation, and free and esterified cholesterol concentrations were determined in each fraction. The cholesteryl ester concentration in all size classes of late passage cells was greater than that of all size classes of early passage cells; the average of all fractions of late passage cells was 2.5 times greater (pg/micrometers 3) and 1.7 times greater (micrograms/mg protein) than that of all fractions of early passage cells (p less than 0.001). The average free cholesterol concentration (micrograms/mg protein) in late passage cell fractions exhibited a consistent, but not statistically significant, increase over that in early passage cells. These results indicate that the increase in cholesteryl ester concentration in late passage WI-38 fibroblasts is not solely attributable to the large, non-dividing cells which accumulate in senescing cultures.
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Cristofalo VJ, Stanulis-Praeger BM. Cellular Senescence in Vitro. ACTA ACUST UNITED AC 1982. [DOI: 10.1016/b978-0-12-007902-5.50007-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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11
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Bladon MT. The expression of hex A and hex B isozymes of hexosaminidase in parental and experimental human fibroblast cells and their components. Biochem Genet 1981; 19:971-86. [PMID: 7332532 DOI: 10.1007/bf00504261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The expression of the two major isozyme forms of hexosaminidase (EC 3.2.1.30), hexosaminidase A and hexosaminidase B, has been examined. The parental cells and/or cellular components of parental cells are individually fused using inactivated Sendai virus with the aid of a micromanipulator. The progeny cells produced from such hybrids are subjected to a microenzymatic assay which allows measurements at the single cell level. The lysosomal-deficient cells used in this study are Tay-Sachs and Sandhoff fibroblasts, and the normal cells used are WI-38 (fetal lung fibroblasts), amniotic fluid cells (GM 473), and JASD3 (normal human foreskin). The results show that the ratio of cell components which are fused to form the experimental cell affects the percentage of hexosaminidase A expressed in the progeny cells. Furthermore, our results imply the presence of a "factor" in the Sandhoff cell's cytoplasm which, together with the Tay-Sachs nucleus, is necessary for hexosaminidase A expression in the experimental cell's progeny.
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12
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Kondo H, Yamamoto K. Effects of in vitro aging and cell growth on the viability and recovery of human diploid fibroblasts, TIG-1, after freezing and thawing. Mech Ageing Dev 1981; 16:117-26. [PMID: 7266075 DOI: 10.1016/0047-6374(81)90088-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The viability and the recovery (cell attachment to the dish) after thawing of human diploid fibroblasts (TIG-1) frozen by four different methods were studied at different passages. Improved results were observed in a medium of 30% fetal bovine serum plus 15% glycerol, compared with the conventional medium which contained 10% fetal bovine serum plus 10% glycerol. Centrifugation to remove glycerol immediately after thawing had a negative effect on the viability and recovery of cells. The recovery of cells after freezing and thawing showed a maximal value in the middle of phase II (PD 35) during the finite lifespan of the cell (average PD 67). This results indicates that the cells at early and late passages are sensitive to injury by freezing and thawing. The modified method yielded improved recovery, especially in the cells at early and late passages, except for the extremely senile stage. The recovery was also affected by the state of cell growth after inoculation.
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13
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Abstract
Cellular research in aging has been stimulated by the observation that human diploid cells have a limited number of cell divisions in culture. This loss of cellular proliferation (in vitro senescence) has been extensively studied by biochemical, clonal, and genetic analysis. Studies of human skin fibroblast cultures have revealed that in vitro senescense is related to in vivo human cellular aging. Recently differentiated cells have been proposed for aging studies. These cells may provide additional information on aging since alterations of in vitro cellular functions may be related to the in vivo behavior of specific differented cell types.
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14
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Raes M, Houbion A, Remacle J. The purification of plasma membranes from WI-38 fibroblasts: effects of ageing on their composition. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 642:313-24. [PMID: 6269614 DOI: 10.1016/0005-2736(81)90448-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A three-step method for the purification of plasma membranes from WI-38 fibroblasts was developed thus allowing the recovery of 36--44% of the plasma membrane. Except in the case of galactosyltransferase, the activity of the contaminating enzymes was very low. Morphological observations confirm the presence of a homogeneous population of vesicles. Preparations obtained from young and old cell cultures were compared for their enzymatic and protein contents. With ageing the activity of 5-nucleotidase significantly increases whereas that of alkaline phosphodiesterase I decreases. Out of the 26 components detected after sodium dodecyl sulphate polyacrylamide gel electrophoresis, four decreased but only one increased. Cellular ageing seems to fulfil a specific and localized effect on the plasma membrane.
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15
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Chen JJ, Brot N, Weissbach H. RNA and protein synthesis in cultured human fibroblasts derived from donors of various ages. Mech Ageing Dev 1980; 13:285-95. [PMID: 6158635 DOI: 10.1016/0047-6374(80)90041-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
RNA synthesis in human fibroblasts from donors of various ages was studied in fibroblasts made permeable to nucleoside triphosphates with the nonionic detergent Nonidet P40. Cells from donors of 11 years and older showed a 30-40% decline in total RNA synthesis. The decrease in RNA synthesis was primarily due to a lowering of RNA polymerase II activity (alpha-amanitin sensitive). Studies on the incorporation of leucine into protein also showed a 30-40% decrease in cells from older donors.
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16
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Kaji H, Hara H, Lamon KD. Fixation of cellular aging processes by SV40 virus transformation. Mech Ageing Dev 1980; 12:197-209. [PMID: 6245312 DOI: 10.1016/0047-6374(80)90095-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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17
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Bradley KH, Kawanami O, Ferrans VJ, Crystal RG. The fibroblast of human lung alveolar structures: a differentiated cell with a major role in lung structure and function. Methods Cell Biol 1980; 21A:37-64. [PMID: 6997687 DOI: 10.1016/s0091-679x(08)60757-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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18
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Le Gall JY, Khoi TD, Glaise D, Le treut A, Brissot P, Guillouzo A. Lysosomal enzyme activities during ageing of adult human liver cell lines. Mech Ageing Dev 1979; 11:287-93. [PMID: 522513 DOI: 10.1016/0047-6374(79)90008-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ten lysosomal enzyme activities have been compared during the growth and ageing of adult human liver cell lines. Arylsulfatase A, beta-D-galactosidase and beta-D-glucuronidase activities were significantly lower and arylsulfatase B activity was significantly higher in senescent cells than in actively growing cells. Furthermore, hexosaminidase activity was lower and acid phosphatase activity higher in old cells in every cell line tested but the differences were not significant. On the other hand, no change occurred in alpha-L-fucosidase, alpha-D-mannosidase, alpha-D-galactosidase and alpha-D-glucosidase activities. These results demonstrate that the increase in size and number of secondary lysosomes during ageing is accompanied for a few lysosomal enzymes by an increase or a decrease in activity depending on the enzyme.
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19
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Abstract
Changes in the cell, nuclear, nucleolar dry masses and areas were monitored simultaneously during in vitro senescence of WI-38 human fetal lung fibroblast cells, and the results were analyzed statistically. There was a two-step increase in all six parameters studied, following an initial decrease. The patterns of increase were strikingly similar for all six measures, i.e., an initial lag period was followed by a sharp increase, a plateau and a final, abrupt increase. In all cases, there was a strong correlation between corresponding area and dry mass measurements for each cell component. The dry mass/area ratio also increased as a function of in vitro aging and ultimately doubled in value. Weak intrapassage correlations between cell, nuclear and nucleolar dry masses indicated that there were passage to passage differences in the relative rates of dry mass increases which were not apparent over long periods of growth. The increases in all muclear and nucleolar areas were interdependent until the last doubling where they increased independently. The standard deviation for all six parameters increased as a function of in vitro senescence indicating that there was an increase in the heterogeneity of cells relative to these parameters.
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20
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Basler JW, David JD, Agris PF. Deteriorating collagen synthesis and cell ultrastructure accompanying senescence of human normal and Werner's syndrome fibroblast cell strains. Exp Cell Res 1979; 118:73-84. [PMID: 759216 DOI: 10.1016/0014-4827(79)90585-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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21
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Bell E, Marek LF, Levinstone DS, Merrill C, Sher S, Young IT, Eden M. Loss of division potential in vitro: aging or differentiation? Science 1978; 202:1158-63. [PMID: 725592 DOI: 10.1126/science.725592] [Citation(s) in RCA: 162] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We have examined the hypothesis that diploid cells grown in vitro age, and propose that only proliferative potential and not life-span is telescoped. We suggest that explanted or transplanted diploid cells are driven to divide by the process of subculturing in vitro or in vivo and, in response to this pressure, also complete their differentiation and become refractory to further mitotic stimulation. We conclude that differentiation rather than "mortality" distinguishes diploid from transformed cells and that the former may not age in vitro, but are lost because culture methods are selective for cycling cells.
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22
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Corfield VA, Hay RJ. Effects of cystine or glutamine restriction on human diploid fibroblasts in culture. IN VITRO 1978; 14:787-94. [PMID: 721103 DOI: 10.1007/bf02617973] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Amino-acid restriction was studied using a strain of human diploid fibroblasts (HDF) isolated from fetal skin. HDF populations were maintained at reduced proliferation rates by lowering cystine or glutamine concentrations of Eagle's MEM. Effects of this treatment on mean cell diameters, total cell protein and specific activity of acid phosphatase were assessed. Threshold levels of cystine required for maintenance were found to be markedly influenced by type and/or batch of serum used irrespective of their free cystine content. A 96-hr exposure of passage 25 cells to medium 0.01 or 0.005 mM in cystine resulted in an increased mean cell diameter and a greater heterogeneity of cell size. This was accompanied by an increase in the total cellular protein. A 48-hr exposure, followed by return to control serial cultivation, induced persistent change in mean cell diameter without affecting the total life span (49 passages over 165 days). The mean size of untreated cells increased with serial passage reaching a size similar to treated cells only at passage 44. Acid-phosphatase specific activities were higher in cells maintained under conditions restrictive in cystine. None of the above changes were observed when glutamine concentrations were reduced to 0.0025 mM, a level required to inhibit division rates. The possible relevance of these findings to the phenomenon of in vitro cell senescence is discussed.
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23
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Kaftory A, Hershko A, Fry M. Protein turnover in senescent cultured chick embryo fibroblasts. J Cell Physiol 1978; 94:147-60. [PMID: 621215 DOI: 10.1002/jcp.1040940204] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The over-all rates of protein synthesis, degradation and net accumulation were estimated in rapidly growing young and slowly doubling old cultures of chick fibroblasts. We find that not only the rate of protein synthesis is reduced in senescent cultures, but the average rate of protein degradation is also slowed down considerably. This decrease in the rate of protein breakdown in aging cells stands in contrast with the previously observed acceleration of this process by other conditions (such as serum deprivation or overcrowding) that lead to the cessation of cellular growth. Though the retarded protein degradation may contribute to the acculation of abnormal proteins in senescent cells we find that the breakdown of grossly abnormal puromycin peptides proceeds equally rapidly in young and old cultures. The protein content of senescent cells increases by 1.8-fold as compared to young cells, while the average cell volume is increased even more (almost 5-fold). By contrast, consideration of the over-all balance of protein metabolism in these cells indicates that the average concentration of metabolically turning-over proteins is somewhat higher in senescent than in young fibroblasts.
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24
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25
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Dreyfus JC, Kahn A, Schapira F. Posttranslational modifications of enzymes. CURRENT TOPICS IN CELLULAR REGULATION 1978; 14:243-97. [PMID: 729396 DOI: 10.1016/b978-0-12-152814-0.50010-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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26
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Ganetzky B, Flanagan JR. On the relationship between senescence and age-related changes in two wild-type strains of Drosophila melanogaster. Exp Gerontol 1978; 13:189-96. [PMID: 99324 DOI: 10.1016/0531-5565(78)90012-8] [Citation(s) in RCA: 89] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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27
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Gahan PB. Increased levels of euploidy as a strategy against rapid ageing in diploid mammalian systems: an hypothesis. Exp Gerontol 1977; 12:113-6. [PMID: 902693 DOI: 10.1016/0531-5565(77)90021-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Wood S. The effect of environmental pH upon acid hydrolase activities of cultured human diploid fibroblasts. Exp Cell Res 1975; 96:317-20. [PMID: 248 DOI: 10.1016/0014-4827(75)90263-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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29
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Schneider EL, Shorr SS. Alteration in cellular RNAs during the in vitro lifespan of cultured human diploid fibroblasts. Cell 1975; 6:179-84. [PMID: 1182799 DOI: 10.1016/0092-8674(75)90008-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
An abrupt concommitant increase in total cellular RNA and protein was observed as cultured human diploid fibroblasts entered the senescent phase of their in vitro lifespan. DNA content remained stable from early to final passages. Fractionation of cellular RNAs by polyacrylamide gel electrophoresis demonstrated an increase in both 28S and 18S ribosomal and 4S transfer RNAs in these senescent cells. Separation of poly(A) RNA (mRNA) by oligo(dT)-cellulose chromatography suggests an increase in this group of RNAs. However, the ratios of 28S to 18S rRNAs, tRNA to rRNA, and mRNA to total cellular RNA were not significantly different in cells before and after senescence, indicating that the overall increases in total cellular RNA was not due to an accumulation of a single RNA class.
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30
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31
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Fulder SJ, Tarrant GM. Possible changes in gene activity during the ageing of human fibroblasts. Exp Gerontol 1975; 10:205-11. [PMID: 241658 DOI: 10.1016/0531-5565(75)90033-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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32
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Mattern MR, Cerutti PA. Age-dependent excision repair of damaged thymine from gamma-irradiated DNA by isolated nuclei from human fibroblasts. Nature 1975; 254:450-2. [PMID: 1118036 DOI: 10.1038/254450a0] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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33
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Ryan JM, Sharf BB, Cristofalo VJ. The influence of culture medium volume on cell density and lifespan of human diploid fibroblasts. Exp Cell Res 1975; 91:389-92. [PMID: 1126392 DOI: 10.1016/0014-4827(75)90119-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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34
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35
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Ryan JM. Alterations in chromatin functions during aging in vitro. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1975; 53:123-36. [PMID: 1119331 DOI: 10.1007/978-1-4757-0731-1_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Age-associated alterations in the chromatin functions of human diploid cells have been observed. These alterations include: (1) a decline in the rate of histone acetylation; (2) a reduction in the rate of RNA synthesis as measured by (a) the rate of 3H-uridine incorporated into the RNA of young and old cells; (b) comparison of the template activity of isolated chromatin from young and old cells using E. coli RNA polymerase and (c) measurement of chromatin template activity using the endogenous RNA polymerase of young and old cells. It is suggested that the nondividing state of old cells may be the result of the inability to synthesize specific RNA molecules (and perhaps specific proteins) necessary for the cell to continue through the cell cycle.
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Dillard CJ, Tappel AL. Beta-acetylhexosaminidases and other acid hydrolases of diploid WI-38 fibroblasts. BIOCHEMICAL MEDICINE 1974; 11:275-89. [PMID: 4433348 DOI: 10.1016/0006-2944(74)90124-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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37
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Turk B, Milo GE. An in vitro study of senescent events of human embryonic lung (WI-38) cells. Arch Biochem Biophys 1974. [DOI: 10.1016/0003-9861(74)90233-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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38
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Choe BK, Rose NR. Synthesis of DNA-binding protein in WI-38 cells stimulated to synthesize DNA by medium replacement. Exp Cell Res 1974; 83:261-70. [PMID: 4361421 DOI: 10.1016/0014-4827(74)90338-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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BeMiller JN, Hoffmann WE, Pappelis AJ. Changes in tRNA methylase activity in senescing cob and stalk parenchyma tissue and the first developed leaf of corn (Zea mays L.). Mech Ageing Dev 1973; 2:363-9. [PMID: 4778854 DOI: 10.1016/0047-6374(73)90030-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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40
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Milisauskas V, Rose NR. Immunochemical quantitation of enzymes in human diploid cell line WI-38. Exp Cell Res 1973; 81:279-84. [PMID: 4202356 DOI: 10.1016/0014-4827(73)90516-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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41
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42
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Itiaba K, Banfalvi M, Crawhall JC. Variations in purine phosphoribosyl transferase enzymes during growth of fibroblast cell cultures. BIOCHEMICAL MEDICINE 1972; 6:495-503. [PMID: 4640187 DOI: 10.1016/0006-2944(72)90002-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Abstract
Immunological and enzymatic assessments of lactate dehydrogenase in human lung fibroblasts strongly suggest that altered proteins accumulate in ageing cells. This supports but does not prove the error catastrophe theory of all death.
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Affiliation(s)
- C M Lewis
- National Institute for Medical Research, Mill Hill
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44
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Lima L, Malaise E, Macieira-Coelho A. Aging in vitro. Effect of low dose rate irradiation on the division potential of chick embryonic fibroblasts. Exp Cell Res 1972; 73:345-50. [PMID: 5066242 DOI: 10.1016/0014-4827(72)90057-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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45
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Abstract
Diploid human fibroblasts accumulate heat labile enzymes during the final stages of their life-span in culture. The RNA base analogue 5-FU induces premature senescence, which is preceded by the appearance of altered enzyme. These observations support Orgel's "error catastrophe" theory of ageing.
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Affiliation(s)
- R Holliday
- National Institute for Medical Research, Mill Hill, London NW7 1AA
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46
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Wang KM. Changes of enzymic activity in mesonephros as a function of age. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1972; 42:143-55. [PMID: 4342451 DOI: 10.1016/0305-0491(72)90067-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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47
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Ryan CA, Lee SY, Nadler HL. Effect of culture conditions on enzyme activities in cultivated human fibroblasts. Exp Cell Res 1972; 71:388-92. [PMID: 5045643 DOI: 10.1016/0014-4827(72)90308-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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48
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Lima L, Macieira-Coelho A. Parameters of aging in chicken embryo fibroblasts cultivated in vitro. Exp Cell Res 1972; 70:279-84. [PMID: 5062035 DOI: 10.1016/0014-4827(72)90137-1] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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49
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