Telomere length and mortality

Abstract

Richard Cawthon and colleagues1Cawthon RM Smith KR O'Brien E Sivatchenko A Kerber RA Association between telomere length in blood and mortality in people aged 60 years or older.Lancet. 2003; 361: 393-395Summary Full Text Full Text PDF PubMed Scopus (1346) Google Scholar report an association between telomere length and mortality in people aged 60 years and older. They suggest that “telomere shortening might not affect mortality, but might be controlled by (and so serve as a useful indicator of) progression of a process of senescence that raises mortality rates by other mechanisms”. I have proposed that the presence of a population of pluripotent stem cells within the bone marrow might indicate a reservoir of cells responsible for postnatal somatic growth, repair, and regeneration (GRR cells).2Campbell K Bone marrow as a reservoir of pluripotential stem cells for somatic growth, repair, and regeneration.http://www.bloodmed.com/400000/reviewarticle1.asp?id=43Google Scholar Within this model, telomere length could be a function, partly or wholly, of the adequacy of this reservoir.Additionally, as suggested by Cawthon and colleagues, the state at a given time would also reflect the extent of recruitment of GRR cells throughout life. Both of these factors might be expected to bear heavily on the ability to withstand illness, infection, or other stress.Deaths from heart disease in Cawthon and colleagues' study were significantly more frequent in the short telomere population than in those with longer telomeres. There have been many reports of apparent recruitment by damaged heart muscle of bone-marrow-derived stem cells. For example, Orlic and colleagues3Orlic D Kajstura J Chimenti S et al.Mobilized bone marrow cells repair the infarcted heart, improving function and survival.Proc Natl Acad Sci USA. 2001; 98: 10344-10349Crossref PubMed Scopus (1931) Google Scholar indicated that cardiac muscle function was significantly improved by treatment with mobilised bone-marrow stem cells. Infection-fighting capacity is highly dependent on the ability to bolster immune-system cell numbers. A depleted reservoir would again be expected to diminish the defences against this potential cause of death.Views expressed in this letter do not necessarily reflect those of the Leukaemia Research Fund. Richard Cawthon and colleagues1Cawthon RM Smith KR O'Brien E Sivatchenko A Kerber RA Association between telomere length in blood and mortality in people aged 60 years or older.Lancet. 2003; 361: 393-395Summary Full Text Full Text PDF PubMed Scopus (1346) Google Scholar report an association between telomere length and mortality in people aged 60 years and older. They suggest that “telomere shortening might not affect mortality, but might be controlled by (and so serve as a useful indicator of) progression of a process of senescence that raises mortality rates by other mechanisms”. I have proposed that the presence of a population of pluripotent stem cells within the bone marrow might indicate a reservoir of cells responsible for postnatal somatic growth, repair, and regeneration (GRR cells).2Campbell K Bone marrow as a reservoir of pluripotential stem cells for somatic growth, repair, and regeneration.http://www.bloodmed.com/400000/reviewarticle1.asp?id=43Google Scholar Within this model, telomere length could be a function, partly or wholly, of the adequacy of this reservoir. Additionally, as suggested by Cawthon and colleagues, the state at a given time would also reflect the extent of recruitment of GRR cells throughout life. Both of these factors might be expected to bear heavily on the ability to withstand illness, infection, or other stress. Deaths from heart disease in Cawthon and colleagues' study were significantly more frequent in the short telomere population than in those with longer telomeres. There have been many reports of apparent recruitment by damaged heart muscle of bone-marrow-derived stem cells. For example, Orlic and colleagues3Orlic D Kajstura J Chimenti S et al.Mobilized bone marrow cells repair the infarcted heart, improving function and survival.Proc Natl Acad Sci USA. 2001; 98: 10344-10349Crossref PubMed Scopus (1931) Google Scholar indicated that cardiac muscle function was significantly improved by treatment with mobilised bone-marrow stem cells. Infection-fighting capacity is highly dependent on the ability to bolster immune-system cell numbers. A depleted reservoir would again be expected to diminish the defences against this potential cause of death. Views expressed in this letter do not necessarily reflect those of the Leukaemia Research Fund.