Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-26T22:34:21.888Z Has data issue: false hasContentIssue false

Protein Turnover During Aging of Cultured Human Fibroblasts

Published online by Cambridge University Press:  29 November 2010

Calvin B. Harley
Affiliation:
McMaster University
Samuel Goldstein
Affiliation:
University of Arkansas for Medical Sciences and GRECC J.L. McClellan Memorial Veterans Hospital

Abstract

When cells are allowed to age in vitro, or are taken from aged normal donors or subjects with features of accelerated aging (progeria or Werner syndrome), they may be considered 'old'. Such old cells have reduced growth rates in culture compared to early or mid-passage cells from young normal donors. During exponential growth the rate constants for protein synthesis were not significantly different between young and old cells (0.023±0.002 h1 vs. 0.021±0.002 h1, respectively), yet growth rates (i.e. protein accretion) were only 0.013±0.003 h1 in old cells compared to 0.022±0.002 h1 in young cells. Thus, the reduced rate of protein accumulation during growth of old cells compared to young cells was associated with increased protein degradation (0.01+0.002 h1 vs. 0.001±0.002 h1; P<0.05) rather than reduced rates of protein synthesis. When cells entered quiescence from density dependent inhibition of growth, protein synthetic rates decreased in both young and old cells to comparable levels (0.013±0.002 h1) with the result that rates of growth (0.003±0.0003 h1) and degradation (0.01±0.003h1) were not significantly different between the two groups. Thus, a difference in protein turnover between young and old cells was only seen during exponential growth, where degradation was increased in old cells. The causal relationship between increased protein degradation and decreased growth rates in old cells is not known.

Résumé

Les cellules qui vieillissent in vitro ou bien celles qui sont prélevées de donneurs d'àge avancé ou de sujets manifestant certaines des particularités qui s'apparentent à un vieillissement accéléré (progérie ou le syndrome de Werner), peuvent être qualifiées de 'vieilles'. Celles-ci on des taux de croissance ralentis en milieu de culture si on les compare aux cellules nouvelles ou à mi-passage prélevées de jeunes donneurs normaux. Durant la croissance exponentielle, les taux de constantes pour la synthèse protéique dans les jeunes cellules ne sont pas significativement différents de ceux retrouvés dans les vieilles cellules (0.023 ± 0.002 h1 vs. 0.021 ± 0.002 h1 respectivement) et pourtant les taux de croissance (i.e. accrétion protéique) sont de seulement 0.013±0.003 h1 dans les vieilles cellules comparés à 0.022±0.002 h1 dans les jeunes cellules. Done, le taux ralenti d'accumulation protéique durant la croissance des vieilles cellules comparé aux jeunes cellules est associé à une dégradation protéique accélérée (0.01±0.002h1 vs 0.001 ±0.002 h1; P <0.05) plutôt qu'à des taux ralentis de synthèse protéique. Lorsque les cellules deviennent quiescentes suivant une période d'inhibition de croissance due à la densité, les taux de synthèse protéique diminuent dans les jeunes et les vieilles cellules pour aboutir à des niveaux comparables (0.013±0.002 h1) où les taux de croissance (0.003±0.0003 h1) et de dégradation (0.01±0.003 h1) ne sont significativement pas differents dans les deux groupes. Done, ce n'est qu'en période de croissance exponentielle qu'une différence dans le turn-over protéique entre jeunes et vieilles cellules est observée, alors que la dégradation est accélérée dans les vieilles cellules. La relation causale entre la dégradation protéique accélérée et les taux de croissance ralentis dans les vieilles cellules demeure inconnue.

Type
Articles
Copyright
Copyright © Canadian Association on Gerontology 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Angello, J.C., Pendergrass, W.R., Norwood, T.H. & Prothero, J. (1989). Cell enlargement: one possible mechanism underlying cellular senescence. J. Cell. Physiol. 140, 288294.CrossRefGoogle ScholarPubMed
Baxter, G.C. & Stanners, C.P. (1978). The effect of protein degradation on cellular growth characteristics. J. Cell. Physiol. 96, 139146.CrossRefGoogle ScholarPubMed
Bond, U. & Schlesinger, M.J. (1985). Ubiquitin is a heat shock protein in chicken embryo fibroblasts. Mol. Cell. Biol. 5, 949956.Google ScholarPubMed
Bradley, M.O., Dice, J.F., Hayflick, L. & Schimke, R.T. (1975). Protein alterations in aging VI38 cells as determined by proteolytic susceptibility. Exp. Cell Res. 96, 103112.CrossRefGoogle Scholar
Bradley, M.O., Hayflick, L. & Schimke, R.T. (1976). Protein degradation in human fibroblasts (WI-38). J. Biol. Chem. 251, 35213529.CrossRefGoogle ScholarPubMed
Cristofalo, V.J. & Kritchevsky, D. (1969). Cell size and nucleic acid content in the diploid human cell line WI-38 during aging. Med. Exp. 19, 313320.Google ScholarPubMed
Dean, R.T. (1980). Protein degradation in cell cultures: general considerations on mechanisms and regulation. Fed. Proc. 39, 1519.Google ScholarPubMed
Dean, R.T. & Riley, P.A. (1978). The degradation of normal and analogue-containing protein in MRC-5 fibroblasts. Biochim. Biophys. Ada 539, 230237.CrossRefGoogle ScholarPubMed
Dice, J.F. (1982). Altered degradation of proteins microinjected into senescent human fibroblasts. J. Biol. Chem. 257, 1462414627.CrossRefGoogle ScholarPubMed
Dice, J.F. (1987). Molecular determinants of protein half-lives in eukaryotic cells. FASEB J. 1, 349357.CrossRefGoogle ScholarPubMed
Engelhardt, D.L., Lee, T.-Y. & Moley, J.F. (1979). Patterns of peptide synthesis in senescent and presenescent human fibroblasts. J. Cell. Physiol. 98, 193198.CrossRefGoogle ScholarPubMed
Goldstein, S. (1978). Human genetic disorders which feature accelerated aging, in The Genetics of Aging, Schneider, E.L., (ed.). Plenum, New York.Google Scholar
Goldstein, S. & Harley, C.B. (1979). In vitro studies of age-associated diseases. Fed. Proc. 38, 18621867.Google ScholarPubMed
Goldstein, S. & Littlefield, J.W. (1969). Effect of insulin on conversion of glucose-C-14 to C-14-O2 by normal and diabetic fibroblasts. Diabetes 18, 545549.CrossRefGoogle ScholarPubMed
Goldstein, S. & Moerman, E.J. (1975a). Heat-labile enzymes in Werner's syndrome fibroblasts. Nature 255, 159.CrossRefGoogle ScholarPubMed
Goldstein, S. & Moerman, E.J. (1975b). Heat-labile enzymes in skin fibroblasts from subjects with progeria. New Eng. J. Med. 292, 13061309.CrossRefGoogle ScholarPubMed
Goldstein, S. & Moerman, E.J. (1976). Defective proteins in normal and abnormal human fibroblasts during aging in vitro. Interdiscipl. Topics Geront. 10, 2443.CrossRefGoogle Scholar
Goldstein, S., Stotland, D., & Cordeiro, R.A.J. (1976). Decreased proteolysis and increased amino acid efflux in aging human fibroblasts. Mech. Ageing Devel. 5, 221233.CrossRefGoogle ScholarPubMed
Harley, C.B. (1990). Aging of cultured human fibroblasts, in Methods in Molecular Biology V: Tissue Culture, Walker, J.M. & Pollard, J.W. (eds.). Humana Press, New Jersey.Google Scholar
Harley, C. B. & Goldstein, S. (1978). Cultured Human Fibroblasts: Distribution of Cell Generations and a Critical Limit. J. Cell. Physiol. 97, 509515.CrossRefGoogle Scholar
Harley, C.B. & Goldstein, S. (1980). Retesting the commitment theory of cellular aging. Science 207, 191193.CrossRefGoogle ScholarPubMed
Harley, C.B., Pollard, J.W., Chamberlain, J.W., Stanners, C.P. & Goldstein, S. (1980). Protein synthetic errors do not increase during aging of cultured human fibroblasts. Proc. Natl. Acad. Sci., USA, 77, 18851889.CrossRefGoogle Scholar
Hayflick, L. (1965). The limited in vitro lifetime of human diploid cell strains. Exp. Cell Res. 37, 614636.CrossRefGoogle ScholarPubMed
Hayflick, L. (1970). Aging under glass. Exp. Geront. 5, 291303.CrossRefGoogle ScholarPubMed
Hayflick, L. & Moorhead, P.S. (1961). The serial cultivation of human diploid cell strains. Exp. Cell Res. 25, 585621.CrossRefGoogle ScholarPubMed
Hendil, K. (1981). Autophagy of metabolically inert substances injected into fibro-blasts in culture. Exp. Cell Res. 135, 157166.CrossRefGoogle Scholar
Hershko, A. & Ciechanover, A. (1982). Mechanisms of intracellular protein break down. Ann. Rev. Biochem. 51, 335364.CrossRefGoogle Scholar
Holliday, R., Porterfield, J.S. & Gibbs, D.D. (1974). Premature aging and occurrence of altered enzyme in Werner's syndrome fibroblasts. Nature 248, 762763.CrossRefGoogle Scholar
Jahngen, J.H., Haas, A.L., Ciechanover, A., Blondin, J., Eisenhauer, D. & Taylor, A. (1986). The eye lens has an active ubiquitin-protein conjugation system. J. Biol. Chem. 261, 1376013767.CrossRefGoogle ScholarPubMed
Lincoln, D.W., Braunschweiger, K.I., Braunschweiger, W.R., & Smith, J.R. (1984). The two-dimensional polypeptide profile of terminally non-dividing human diploid cells. Exp. Cell Res. 154, 136146.CrossRefGoogle ScholarPubMed
Manetto, V., Perry, G., Tabaton, M., Mulvihill, P., Fried, V.A., Smith, H.T., Gambetti, P. & Autilio-Gambetti, L. (1988). Ubiquitin is associated with abnormal cytoplasmic filaments characteristic of neurodegenerative diseases. Proc. Natl. Acad. Sci., USA, 85, 45014505.CrossRefGoogle ScholarPubMed
McKee, E.E., Cheung, J.Y., Rannels, D.E. & Morgan, H.E. (1978). Measurement of the rate of protein synthesis and compartmentation of heart phenylalanine. J. Biol. Chem. 253, 10301040.CrossRefGoogle ScholarPubMed
Mortimore, G.E., Lardeux, B.R. & Adams, C.E. (1988). Regulation of micro-autophagy and basal protein turnover in rat liver. J. Biol. Chem. 263, 25062512.CrossRefGoogle Scholar
Okada, A.A. & Dice, J.F. (1984). Altered degradation of intracellular proteins in aging human fibroblasts. Mech. Ageing Devel. 26, 341356.CrossRefGoogle ScholarPubMed
Oliver, C.N., Ahn, B., Moerman, E.J., Goldstein, S. & Stadtman, E.R. (1987). Agerelated changes in oxidized proteins. J. Biol. Chem. 262, 54885491.CrossRefGoogle ScholarPubMed
Pardee, A.B., Coppock, D.L. & Yang, H.C. (1986). Regulation of cell proliferation at the onset of DNA synthesis. J. Cell. Sci., Suppl. 4, 171180.CrossRefGoogle ScholarPubMed
Pontremoli, S. & Melloni, E. (1986). Extralysosomal protein degradation. Ann. Rev. Biochem. 55, 455481.CrossRefGoogle ScholarPubMed
Stanulis-Praeger, B.M. (1987). Cellular senescence revisited: a review. Mech. Age. Dev. 38, 148.CrossRefGoogle ScholarPubMed
Wilson, D.L., Hall, M.E. & Stone, G.C. (1978). Test of some aging hypotheses using two-dimensional protein mapping. Geront. 24, 426433.CrossRefGoogle ScholarPubMed
Wojtyk, R.I. & Goldstein, S. (1980). Fidelity of protein synthesis does not decline during aging of cultured human fibroblasts. J. Cell. Physiol. 103, 299303.CrossRefGoogle Scholar