Get 20M+ Full-Text Papers For Less Than $1.50/day. Subscribe now for You or Your Team.

Learn More →

Telomeres shorten at equivalent rates in somatic tissues of adults

Telomeres shorten at equivalent rates in somatic tissues of adults ARTICLE Received 3 Aug 2012 | Accepted 14 Feb 2013 | Published 19 Mar 2013 | Updated 24 Jul 2013 DOI: 10.1038/ncomms2602 OPEN Telomeres shorten at equivalent rates in somatic tissues of adults 1 2,3 4,5 6 2,3 7 Lily Daniali , Athanase Benetos , Ezra Susser , Jeremy D. Kark , Carlos Labat , Masayuki Kimura , 1 1 7 Kunj K. Desai , Mark Granick & Abraham Aviv Telomere shortening in somatic tissues largely reflects stem cell replication. Previous human studies of telomere attrition were predominantly conducted on leukocytes. However, findings in leukocytes cannot be generalized to other tissues. Here we measure telomere length in leukocytes, skeletal muscle, skin and subcutaneous fat of 87 adults (aged 19–77 years). Telomeres are longest in muscle and shortest in leukocytes, yet are strongly correlated between tissues. Notably, the rates of telomere shortening are similar in the four tissues. We infer from these findings that differences in telomere length between proliferative (blood and skin) and minimally proliferative tissues (muscle and fat) are established during early life, and that in adulthood, stem cells of the four tissues replicate at a similar rate. Division of Plastic Surgery, Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 2 3 07103, USA. Geriatric Service, Nancy University Hospital, Nancy 54511, France. Inserm U961, Faculty of Medicine, Universite de Lorraine, Nancy 54500, 4 5 France. Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York 10032, USA. New York State Psychiatric Institute, New York, New York 10032, USA. Epidemiology Unit, The Hebrew University–Hadassah School of Public Health and Community Medicine, Ein Kerem, Jerusalem 91120, Israel. The Center of Human Development and Aging, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103, USA. Correspondence and requests for materials should be addressed to A.A. (email: avivab@umdnj.edu). NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications 1 & 2013 Macmillan Publishers Limited. All rights reserved. ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 elomere length (TL) is equivalent in different somatic hematopoietic system explains the infrequent replication of 1–3 7,16,17,20 tissues of the human fetus and newborn . This hematopoietic stem cells in adults at the top of the Tequivalence at birth is owing in part to the activity of hierarchy in spite of the massive turnover of circulating blood telomerase , which counteracts TL shortening resulting from cell cells at its bottom. It also explains the relatively slow rate of age- 13,14 replication during early intra-uterine growth. During extra- dependent leukocyte TL shortening in adulthood , which uterine life, telomerase activity is largely repressed in somatic largely reflects ‘maintenance’ replicative activity of hematopoietic 5,6 tissues, including in hematopoietic stem cells ; hence TL varies stem cells, that is, any replicative activity that is not related to across somatic tissues in proportion to replicative activity. growth and development. Notably, leukocyte TL, which reflects TL in hematopoietic stem Data are available about leukocyte TL dynamics (TL and its 3,7 cells , is shorter than TLs of minimally proliferative somatic age-dependent attrition), and by inference these data also enable 8,9 tissues . Yet, the available data from human studies point to us to understand much about the replicative kinetics of 7,16,17,20 strong correlations in TL across somatic tissues, that is, hematopoietic stem cells in vivo . But no such individuals with long (or short) TL in one tissue also have long information exists, to our knowledge, for other somatic tissues. (or short) TL in other tissues. This ‘synchrony’ in TL across Based on quantifying C in genomic DNA from somatic tissues, 1,2,8–10 somatic tissues has been observed not only in humans but skeletal muscle (hereafter referred to as muscle) and fat do 11,12 also other mammals, including non-human primates . experience some replication, presumably of stem cells/progenitor 21,22 Previous reports on the age-dependent attrition of TL in cells . In the present study, we examined TL measures and humans are based primarily on studies of leukocytes. These age-dependent TL attrition in four tissues in a cross-sectional studies suggest that the rate of age-dependent leukocyte TL study spanning more than five decades of adult life. Our findings shortening is rapid early in life but slows down during adulthood indicate that during adulthood, age-dependent TL shortening is 13,14 15 in both humans and in non-human primates . Furthermore, similar in all four tissues regardless of their replicative activity. simulations of TL dynamics in granulocytes and leukocytes have This unexpected result provides an important insight with respect been used to gauge the replicative kinetics of hematopoietic stem to stem cell/progenitor cell replicative kinetics and their potential 7,16,17 cells . The findings of such simulations suggest that the rapid links to aging and longevity in humans. leukocyte TL attrition during the first two decades of the human life course reflects the expansion of the hematopoietic stem cell Results and hematopoietic progenitor cell pools. This expansion involves Subject characteristics. Participants consisted of 61 women and both symmetric cell divisions in which a hematopoietic stem cell 26 men (Table 1), 35 Blacks and 52 whites (33 Hispanics and 19 divides into two daughter hematopoietic stem cells, and non-Hispanic whites) with an age range of 19–77 years. Hispanics asymmetric cell divisions in which a hematopoietic stem cell and non-Hispanic whites were grouped as whites for comparison divides into one hematopoietic stem cell and one hematopoietic 18 with Blacks (Table 2), as no differences were observed between progenitor cell . Hispanics and non-Hispanic whites with respect to variables of Growth and development require only a few symmetric interest, including TLs in the four tissue types (leukocytes, replications of hematopoietic stem cells. By contrast, the vast muscle, skin and fat). expansion of the hematopoietic progenitor cell pool requires numerous asymmetric replications of hematopoietic stem cells . In this way, the incrementally larger and more differentiated TLs of the subjects. TL was longest in muscle and shortest in pools and sub-pools of hematopoietic progenitor cells, down the leukocytes (Table 1) (Po0.0001 (paired Wilcoxon signed-rank hematopoietic hierarchy, are able to maintain homeostasis of test) for all comparisons). In univariate analysis, TL was longer in circulating blood cells. During growth and development, women than in men for leukocytes and for muscle (Table 1). In homeostasis must accommodate both the expansion of the addition, Blacks displayed a longer TL than whites in leukocytes hematopoietic system and the staggeringly high rate of turnover and muscle (Table 2). In multivariable analysis that included age, of some blood cells, which persists throughout life. For instance, sex, body mass index and ethnicity/race (Table 3), age explained B100 billion neutrophils are mobilized from the bone marrow of 17.5% of the inter-individual variation in leukocyte TL, 8.2% of adult humans each day . This hierarchical feature of the muscle TL, 10.5% of skin TL and 12.4% of fat TL. Table 1 | Demographic characteristics and TL parameters for the entire cohort and by sex. All Men Women Number 87 26 61 ± ± ± Age (years) 44 14 (19–77) 46 18 (19–77) 44 11 (20–68) Sex (%) 100 30 70 Blacks (%) 40 27 46 Whites (%) 21 35 16 Hispanics (%) 38 38 38 ± ± ± BSA (m ) 2.02 0.31 (1.58–3.30) 2.09 0.36 (1.58–3.30) 1.99 0.29 (1.59–2.75) ± ± ± BMI (kg m)33 9 (18–63) 31 9 (18–62) 34 9 (23–63) ± ± ± Leukocyte TL (kb) 7.02 0.86 (4.52–10.25) 6.77 1.16 (4.52–10.25) 7.13 0.67 (5.89–9.13)* ± ± ± Muscle TL (kb) 8.55 0.94 (5.86–11.53) 8.15 1.13 (5.86–10.35) 8.72 0.79 (7.33–11.53)* ± ± ± Skin TL (kb) 7.29 0.90 (5.03–10.44) 7.16 1.12 (5.03–10.07) 7.35 0.79 (5.63–10.44) ± ± ± Fat TL (kb) 8.18 0.93 (5.17–10.68) 8.10 1.20 (5.17–10.68) 8.21 0.80 (6.48–10.68) BMI, body mass index; BSA, body surface area; TL, telomere length; Whites, non-Hispanic Whites. *Po0.05 women versus men. Values are mean s.d. (min—max) or %. Wilcoxon rank-sum test for difference in medians or w . 2 NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications & 2013 Macmillan Publishers Limited. All rights reserved. NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 ARTICLE Rates of age-dependent TL attrition. Cross-sectional analysis skin¼ 5.03–10.44 kb; fat¼ 5.17–10.68 kb (Table 1). Individuals indicated that the four somatic tissues displayed significant but showed strong correlations of TL between tissues, such that those similar age-dependent TL attritions per year (mean s.e.m.): with long (or short) TL in one tissue typically displayed long (or ± ± ± leukocytes¼ 26 6 bp; muscle¼ 24 7 bp; skin¼ 23 7 bp; and short) TL in other tissues (r¼ 0.72–0.84, Po0.0001; Pearson’s fat¼ 25 7 bp (Fig. 1). Consequently, the average differences (D) correlation) for each possible pairing of tissue types (Fig. 3). The in TL between the four tissues were stable throughout the association of leukocyte TL with the other three tissues was also 5-decade age range (Fig. 2). consistently high (r¼ 0.83–0.84, Po0.0001; Pearson’s correlation) for each pairing irrespective of the proliferative nature of the tissue. Comparisons of TLs across somatic tissues. TLs in all four tis- Discussion sues displayed wide inter-individual variation in the following ranges: leukocytes¼ 4.52–10.25 kb; muscle¼ 5.86–11.53 kb; Three central conclusions can be drawn from this study. First, across more than five decades of adult life, despite different replicative status, leukocytes, muscle, skin and fat displayed Table 2 | Demographic characteristics and TLs parameters similar rates of age-dependent TL attrition. Second, in accord for Blacks and Whites. with this result, differences in TLs between the tissues showed no significant change throughout the age range. We infer, therefore, Blacks Whites that the TL differences between the tissues were largely Number 35 52 established at a younger age, during the first two decades of life. ± ± Age (years) 41.58 12.18 (19.31–67.16) 46.09 14.47 (19.59–77.38) Third, we confirmed observations from previous limited studies Women (%) 80 63 BSA (m ) 2.09±0.29 (1.59–2.75) 1.97±0.33 (1.58–3.30)* that there is an intra-individual synchrony in TL across the ± ± 1–3,8–10 BMI (Kg m)35 8 (23–48) 32 9 (18–63) somatic tissues of humans as evidenced by the strong ± ± Leucocytes TL (kb) 7.25 0.71 (5.89–9.13) 6.87 0.92 (4.52–10.25)* correlations observed between the TLs in all tissue type pairings. ± ± Muscle TL (kb) 8.88 0.91 (6.55–11.53) 8.33 0.90 (5.86–10.38)** ± ± Skin TL (kb) 7.33 0.71 (5.63–8.53) 7.27 1.02 (5.03–10.44) This intra-individual synchrony in TL across somatic tissues is ± ± Fat TL (kb) 8.26 0.81 (6.48–9.61) 8.13 1.00 (5.17–10.68) 11,12 also seen in other mammals . The finding that four somatic tissues, which are characterized BMI, body mass index; BSA, body surface area; TL, telomere length. *Po0.05; **Po0.01 Blacks versus Whites. by vastly differing rates of proliferation, showed similar rates of Values are mean s.d. (min—max) or %. TL attrition across the adult life span was entirely unexpected. A Wilcoxon rank-sum test for difference in medians or w . cross-sectional study of ten individuals, including neonates, found no evidence of TL shortening in muscle across more than eight decades . Similarly, another study, comprising 16 subjects (mean age 25 years) and 26 subjects (mean age 74 years), concluded that Table 3 | Determinants of tissue TL (univariate and there was no evidence of age-dependent muscle TL attrition multivariate analysis). during adulthood . In our much larger, albeit still modestly sized sample population, we used a more accurate method of TL Univariate Multivariate measurement and clearly draw a different conclusion. 2 2 R (%) PR (%) P Longitudinal studies have reported considerable inter-indivi- Leucocyte TL dual variation in the rate of leukocyte TL shortening among Age 17.5 0.0002 17.5 0.0002 25,26 adults . The same presumably applies to TL attrition in other Sex 3.6 0.08 — 0.13 27–29 somatic tissues. Although leukocyte TL is largely heritable , BMI 0.6 0.50 — 0.58 environmental factors may influence its dynamics. For instance, Race/ethnicity 4.8 0.042 — 0.14 30–32 30,31 cigarette smokers , obese persons and those with a Model 17.5 Muscle TL Leukocytes Muscle y = –0.024x + 9.60 Age 11.7 0.001 8.2 0.004 12 y = –0.026x + 8.18 12 R = 0.12; P =0.002 R = 0.17 P =0.00006 Sex 7.9 0.008 4.8 0.027 Men Men BMI 0.9 0.39 — 0.12 10 10 Women Women Race/ethnicity 8.2 0.007 3.8 0.047 Model 22.0 8 8 Skin TL 6 6 Age 12.5 0.0008 10.5 0.002 Sex 1.0 0.35 — 0.36 4 4 0 20406080 100 0 20406080 100 BMI 4.6 0.049 3.9 0.055 Age (years) Age (years) Race/ethnicity 0.1 0.76 — 0.95 Model 15.0 Skin Fat 12 12 y = –0.023x + 8.32 y = –0.025x + 9.27 2 2 R = 0.13; P =0.0008 R = 0.13; P =0.0005 Fat TL 10 Men 10 Men Age 13.3 0.0005 12.4 0.001 Women Women Sex 0.3 0.62 — 0.67 8 8 BMI 5.7 0.03 4.9 0.03 Race/ethnicity 0.5 0.51 — 0.58 6 6 Model 18.1 BMI, body mass index; TL, telomere length. 4 4 0 20 40 60 80 100 0 20 40 60 80 100 The associations of age, sex, BMI (continuous variables) and race/ethnicity (Blacks versus others) with TL were tested in univariate and multivariate models. R represents the contribution Age (years) Age (years) (%) of each of the variables to TL. Only R values of variables that were significantly associated with leukocyte TL in the multivariate analysis are shown. R of the model represents the joint Figure 1 | Correlation between TL and age in various tissues. TL in contribution to TL of the tested variables in the multivariate analysis. leukocytes, muscle, skin and fat is plotted against age. NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications 3 & 2013 Macmillan Publishers Limited. All rights reserved. Telomere length (kb) Telomere length (kb) Telomere length (kb) Telomere length (kb) ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 Leukocytes–muscle Leukocytes–fat Leukocytes–skin 1 1 1 0 0 0 –1 –1 –1 –2 –2 –2 –3 –3 –3 Men y = –0.0025x –1.42 Men y = –0.0014x –1.10 Men y = –0.0028x –0.15 2 2 2 Women R = 0.0046; P = 0.51 Women R = 0.0013; P = 0.73 Women R = 0.0056; P =0.48 –4 –4 –4 0 20 40 60 80 100 0 20 40 60 80 100 0 20 40 60 80 100 Age (years) Age (years) Age (years) Skin–muscle Skin–fat Fat–muscle 1 1 1 0 0 0 –1 –1 –1 –2 –2 –2 –3 –3 –3 Men y = 0.0003x –1.27 Men y = 0.0014x –0.95 y = –0.0012x –0.32 Men 2 2 2 Women R = <0.0001; P = 0.97 Women R = 0.0015; P = 0.71 Women R = 0.0006; P = 0.80 –4 –4 –4 0 20 40 60 80 100 0 20 40 60 80 100 0 20 40 60 80 100 Age (years) Age (years) Age (years) Figure 2 | Differences in TL in tissues are stable. Differences in TL (D) between tissues within the same individuals are plotted against the ages of the donors of the samples. 12 y = 0.77x + 0.45 12 y = 0.77x + 0.72 12 y = 0.79x + 1.27 2 2 2 R = 0.71; P <0.0001 R = 0.69; P <0.0001 R = 0.69; P <0.0001 Men Men Men 10 10 10 Women Women Women 8 8 8 6 6 6 4 4 4 4 6 8 10 12 4 6 8 10 12 4 6 8 10 Muscle telomere length (kb) Fat telomere length (kb) Skin telomere length (kb) 12 12 12 y = 0.69x + 1.41 y = 0.82x + 0.59 y = 0.76x + 1.72 2 2 2 R = 0.51; P <0.0001 R = 0.71;P <0.0001 R = 0.59; P <0.0001 Men Men Men 10 10 10 Women Women Women 8 8 8 6 6 6 4 4 4 46 810 12 46 810 12 46 810 Muscle telomere length (kb) Fat telomere length (kb) Muscle telomere length (kb) Figure 3 | Equivalence in TL between tissues within the same individual. Although the correlations between TLs of the four tissues are strong, the highly proliferative tissues (leukocytes and skin) consistently display shorter telomeres than the minimally proliferative tissues (muscle and fat). 33,34 sedentary lifestyle have typically shown shorter leukocyte assuming that telomere loss per division is the same in all somatic TLs, presumably owing to an increased burden of inflammation, tissues, it seems that during adult life the rates of replicative which might accelerate hematopoietic stem cell divisions, and activity of stem cells are similar in proliferative and minimally oxidative stress, which might augment their telomere shortening proliferative tissues. per replication. Endurance running, in contrast, apparently We propose that the differences in TL between somatic tissues shortens TL in muscle perhaps owing to heightened of adults largely arise from the expansion during growth and proliferation of stem cells/progenitor cells (satellite cells) to development of the stem cell pool through both symmetric stem build/repair muscle tissue . Thus, the rates of TL attrition in cell divisions and more so for the progenitor cell pool, through both proliferative and minimally proliferative tissues during adult asymmetric stem cell divisions. Theoretically, o5 rounds of life may be modified by a variety of factors. This may account in symmetric divisions of the entire hematopoietic stem cell pool are part for the large inter-individual variation of D in TLs between necessary to expand the compartment in tandem with an increase tissues within individuals (Fig. 2). Still, as age-dependent TL in body weight from 3 kg of birth weight to 80 kg adult weight, attrition ultimately reflects division in the stem cell pool, and that is, 3–6 kg (first round); 6–12 kg (second round); 12–24 kg 4 NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications & 2013 Macmillan Publishers Limited. All rights reserved. Δ Telomere length (kb) Δ Telomere length (kb) Skin telomere length (kb) Leukocyte telomere length (kb) Δ Telomere length (kb) Δ Telomere length (kb) Skin telomere length (kb) Leukocyte telomere length (kb) Δ Telomere length (kb) Δ Telomere length (kb) Fat telomere length (kb) Leukocyte telomere length (kb) NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 ARTICLE (third round); 24–48 kg (fourth round); and 48–96 kg (fifth transplant , with the rebuilding of both the hematopoietic stem round) . Therefore, to accommodate growth, the impact of the cell pool and also the hematopoietic progenitor cell pool. expansion of the hematopoietic stem cell pool on leukocyte TL is Nevertheless, the strong correlations noted between all pairings relatively small. This is also likely to be the case for TL dynamics of tissue types, irrespective of their replicative potential, suggest 1,2 in other somatic tissues, including minimally proliferative ones. that the initial equivalence of TL in utero and at birth continues In contrast, numerous asymmetric divisions of hematopoietic to dominate the TL phenotypic landscape across the lifespan, and stem cells are required during growth to build the large that accelerated stem cell division during growth and development hematopoietic progenitor cell pool in order to maintain the after birth exerts a more modest effect that reduces this numbers of circulating blood cells, a subset of which has an equivalence. Thus, the main contributors to TL and its similarity enormous turnover . Consequently, as illustrated in Fig. 4, in individuals are primarily prenatal, followed by growth in leukocyte TL undergoes considerable shortening during early childhood and adolescence, with less influence in adulthood. 7,13–15 life . The same might apply, although to a lesser extent, to We acknowledge a number of shortcomings of this study. other highly replicative somatic tissues, such as skin. In contrast, First, our study was cross-sectional in design; we used tissues the expansions of progenitor cell pools during growth and obtained during elective surgical procedures from individuals development in minimally proliferative tissues, such as muscle of different ages to compute TL dynamics. Ideally, measurement and fat, are probably limited. The sizes of these progenitor cell of age-dependent TL attrition should be performed longitudinally pools may be calibrated to accommodate only small cell turnover in the same individuals, but this was simply not feasible. Second, rates in adulthood. Accordingly, early in life, TLs of muscle and the samples of muscle, skin and fat were obtained from different other minimally proliferative tissues undergo substantially less sites, but we doubt that body region exerted any influence on the findings. We found no evidence that surgical site (head and neck, attrition than leukocyte TL (Fig. 4). The need to establish a huge thorax, abdomen, upper extremities and lower extremities) hematopoietic progenitor cell pool may be the reason that bone impacted TL without and with adjustment for age. Third, marrow failure is the first catastrophic manifestation arising from leukocyte TL is derived from circulating cells, which are major mutations in telomere maintenance genes . It also explains partitioned from the less mature hematopoietic cells in the bone the rapid leukocyte TL shortening post hematopoietic stem cell marrow. In contrast, TLs in solid tissues reflect TL of fully differentiated cells as well as resident stem cells/progenitor cells. However, we doubt that TLs of these precursor cells exert an appreciable influence on the mean TLs in muscle and other Hematopoietic cells minimally proliferative tissues, because, as discussed above, the size of the stem cell/progenitor cell pools in these tissues is very small. Furthermore, although we examined several fold more patients than in previous studies, our sample size remains modest and requires extension. In conclusion, in adults, both highly proliferative and minimally proliferative tissues appear to display similar age- Skeletal muscle dependent telomere attrition. Moreover, in this study population, the average gap in TLs between the proliferative and minimally proliferative tissues was essentially constant between the ages of Age 19–77 years, suggesting that the first 20 years of life is a crucial time period for establishing this difference. As TL dynamics largely reflect stem cell kinetics, we infer that stem cell division rates for maintenance might be similar in the somatic tissues we Skeletal muscle examined, regardless of their proliferative status. Making clinical use of TL in predicting future health risks will depend to a large extent on understanding the underlying inter-individual varia- tions in TL at birth and its attrition during human growth and development. Hematopoietic cells Methods Recruitment of study participants. Inpatients and outpatients scheduled for general, plastic and vascular surgery at the University Hospital of the University of Age Medicine and Dentistry of New Jersey were approached by the study coordinator for participation in this investigation. These also included patients undergoing Figure 4 | Model of progenitor cell pool dynamics and in different surgical procedures to remove cancer with no evidence of metastasis. This research tissues. Upper panel: during growth (grey shade), the progenitor cell pool was approved by the Institutional Review Board (IRB) of the University of Med- in the hematopoietic system undergoes massive expansion through icine and Dentistry of New Jersey, New Jersey Medical School. All participants signed a written informed consent approved by the IRB. Participants were asked to asymmetric replication of hematopoietic stem cells. In this way, the system donate blood (from the intravenous line or phlebotomy) and B50–100 mg spe- can accommodate the tremendous turnover in peripheral blood cells. In cimens of skin, subcutaneous fat and skeletal muscle in the surgical field. If the contrast, during growth, the progenitor cell pool in skeletal muscle attending surgeon indicated the study coordinator that one of the tissue types could undergoes a modest expansion through replication of muscle stem cells, as not be sampled during the surgery, the potential study subject was not approached for enrolment. Similarly, all subjects who had received therapeutic irradiation to the turnover of skeletal muscle cells is small. Lower panel: reflecting the the surgical site and those with a history of immunosuppression secondary to a expansions of the progenitor cell pools in the respective systems, TL medical condition or of chemotherapy for cancer treatment were not enroled. undergoes rapid attrition in the hematopoietic system but only modest Three subjects were excluded owing to HIV infection and sickle cell disease. attrition in skeletal muscle. The slow and parallel attritions of TLs in stem cells, as expressed in leukocyte TL and in skeletal muscle TL during adult Measurements of TL. DNA integrity was evaluated by resolving samples on 1% life, are the outcome of ’maintenance’ replicative activities of stem cells/ (wt/vol) agarose gel. Samples were digested with restriction enzymes Hinf I (10 U) progenitor cells in these systems. and Rsa I (10 U; Roche). Digested DNA samples and DNA ladders were resolved NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications 5 & 2013 Macmillan Publishers Limited. All rights reserved. Telomere length Progenitor cell pool ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 on 0.5% agarose gels. After 16 h, the DNA was depurinated for 15 min in 0.25 N 24. Ponsot, E., Lexell, J. & Kadi, F. Skeletal muscle telomere length is not impaired HCl, denatured 30 min in 0.5 M NaOH/1.5 mol l NaCl and neutralized for in healthy physically active old women and men. Muscle Nerve 37, 467–472 30 min in 0.5 mol l Tris, pH 8/1.5 M NaCl. The DNA was transferred for 1 h to a (2008). positively charged nylon membrane (Roche) using a vacuum blotter (Boeckel 25. Chen, W. et al. Longitudinal versus cross-sectional evaluations of leukocyte Scientific, Feasterville, PA). Membranes were hybridized at 65 C with the DIG- telomere length dynamics: age-dependent telomere shortening is the rule. labelled telomeric probe overnight as previously described . The DIG-labelled J. Gerontol. A Biol. Sci. Med. Sci. 66, 312–319 (2011). probe was detected by the DIG luminescent (Roche) and exposed on X-ray film. 26. Kark, J. D., Goldberger, N., Kimura, M., Sinnreich, R. & Aviv, A. Energy intake The inter-assay coefficient of variation of the TL measurements was 1.8%. and leukocyte telomere length in young adults. Am. J. Clin. Nutr. 95, 479–487 (2012). 27. Slagboom, P. E., Droog, S. & Boomsma, D. I. Genetic determination of telomere Statistical analysis. Descriptive values are expressed as mean s.d., number of size in humans: a twin study of three age groups. Am. J. Hum. Genet. 55, patients and percentages. The population was divided according to sex or ethnicity/ 876–882 (1994). race, and compared using the Wilcoxon rank-sum test or the w test. Comparisons 28. Andrew, T. et al. Mapping genetic loci that determine leukocyte telomere of TL among different tissues were performed using a paired Wilcoxon signed-rank length in a large sample of unselected, female sib-paternal age influencers. Am. test. A P-value o0.05 was regarded as statistically significant. Relationships J. Hum. Genet. 78, 480–486 (2006). between TL and age in the four tissues (by pairs) were determined using Pearson’s 29. Jeanclos, E. et al. Telomere length inversely correlates with pulse pressure and is correlation coefficients. The effects of age, sex, race/ethnicity and body mass index highly familial. Hypertension 36, 195–200 (2000). were evaluated in a multiple regression analysis by including the variables asso- 30. Strandberg, T. E. et al. Association of telomere length in older men with ciated with TL that had a P-value o0.10 in the univariate analysis. Statistical analyses were carried out using the NCSS 2004 statistical software package. mortality and midlife body mass index and smoking. J. Gerontol. A Biol. Sci. Med. Sci. 66, 815–820 (2011). 31. Valdes, A. M. et al. Obesity, cigarette smoking, and telomere length in women. References Lancet 366, 662–664 (2005). 1. Youngren, K. et al. Synchrony in telomere length of the human fetus. Hum. 32. Nawrot, T. S., Staessen, J. A., Gardner, J. P. & Aviv, A. Telomere length and Genet. 102, 640–643 (1998). possible link to X chromosome. Lancet 363, 507–510 (2004). 2. Okuda, K. et al. Telomere length in the newborn. Pediatr. Res. 52, 377–381 (2002). 33. Cherkas, L. F. et al. The association between physical activity in leisure time and 3. Kimura, M. et al. Synchrony of telomere length among hematopoietic cells. leukocyte telomere length. Arch. Intern. Med. 168, 154–158 (2008). Exp. Hematol. 38, 854–859 (2010). 34. LaRocca, T. J., Seals, D. R. & Pierce, G. L. Leukocyte telomere length is 4. Blackburn, E. H. Telomeres and telomerase: their mechanisms of action and the preserved with aging in endurance exercise-trained adults and related to effects of altering their functions. FEBS Lett. 579, 859–862 (2005). maximal aerobic capacity. Mech. Ageing Dev. 131, 165–167 (2010). 5. Yui, J., Chiu, C. P. & Lansdorp., P. M. Telomerase activity in candidate stem 35. Rae, D. E., Vignaud, A., Butler-Browne, G. S., Thornell, L. E. & Sinclair-Smith, cells from fetal liver and adult bone marrow. Blood 91, 3255–3262 (1998). C. Muscle telomere length in healthy, experienced, endurance runners. Eur. J. 6. Morrison, S. J., Prowse, K. R., Ho., P. & Weissman, I. L. Telomerase activity Appl. Physiol. 109, 323–330 (2010). in hematopoietic cells is associated with self-renewal potential. Immunity 5, 36. Calado, R. T. & Young, N. S. Telomere diseases. N. Engl. J. Med. 361, 207–521 (1996). 2353–2365 (2009). 7. Sidorov, I., Kimura, M., Yashin, A. & Aviv, A. Leukocyte telomere dynamics 37. Gadalla, S. M. & Savage, S. A. Telomere biology in hematopoiesis and stem cell and human hematopoietic stem cell kinetics during somatic growth. Exp. transplantation. Blood Rev. 25, 261–269 (2011). Hematol. 37, 514–524 (2009). 38. Kimura, M. et al. Measurement of telomere length by the Southern blot 8. Granick, M. et al. Telomere dynamics in keloids. Eplasty 11, e15 (2011). analysis of terminal restriction fragment lengths. Nat. Protoc. 5, 1596–1607 9. Gardner, J. P. et al. Telomere dynamics in macaques and humans. J. Gerontol. (2010). A Biol. Sci. Med. Sci. 62, 367–374 (2007). 10. Friedrich, U. et al. Telomere length in different tissues of elderly patients. Mech. Acknowledgements Ageing Dev. 119, 89–99 (2000). This work has been supported by NIH grants AG16592, AG030678, HD071180 11. Benetos, A. et al. A model of canine leukocyte telomere dynamics. Aging Cell MH059114, the US-Israel Binational Science Foundation, the Israel Science Foundation, 10, 991–995 (2011). the Fondation pour la Recherche Medicale (FRM DCV- 20070409250), the Agence 12. Smith, Jr D. L. et al. Telomere dynamics in rhesus monkeys: no apparent effect Nationale de la Recherche (ANR 09-GENO-010-01) and the Plan Pluri-Formation of caloric restriction. J. Gerontol. A Biol. Sci. Med. Sci. 66, 1163–1168 (2011). (French Ministry of Research). 13. Aubert, G., Baerlocher, G. M., Vulto, I., Poon, S. S. & Lansdorp, P. M. Collapse of telomere homeostasis in hematopoietic cells caused by heterozygous mutations in telomerase genes. Plos Genet. 8, e1002696 (2012). Author contributions 14. Frenck, R. W., Blackburn, E. H. & Shannon, K. M. The rate of telomere L.D. participated in study design, sample and data collections and writing the manu- sequence loss in human leukocytes varies with age. Proc. Natl Acad. Sci. USA script. A.B. participated in study design, analysis of data and writing the manuscript. 95, 5607–5610 (1998). E.S. participated in data analysis and writing the manuscript. J.D.K. participated in data 15. Baerlocher, G. M., Rice, K., Vulto, I. & Lansdorp, P. M. Longitudinal data on analysis and writing the manuscript. C.L. oversaw data analysis and participated in telomere length in leukocytes from newborn baboons support a marked drop in writing the manuscript. M.K. oversaw TL measurements. K.D. participated in sample stem cell turnover around 1 year of age. Aging Cell 6, 121–123 (2007). collections. M.G. participated in study design and oversaw sample collections. A.A. 16. Shepherd, B. E., Guttorp, P., Lansdorp, P. M. & Abkowitz, J. L. Estimating conceived the study and its design, oversaw the entire project and participated in writing human hematopoietic stem cell kinetics using granulocyte telomere lengths. the manuscript. Exp. Hematol. 32, 1040–1050 (2004). 17. Shepherd, B. E. et al. Hematopoietic stem-cell behavior in nonhuman primates. Additional information Blood 110, 1806–1813 (2007). Supplementary Information accompanies this paper at http://www.nature.com/ 18. Morrison, S. J. & Kimble, J. Asymmetric and symmetric stem-cell divisions in naturecommunications development and cancer. Nature 441, 1068–1074 (2006). 19. Furze, R. C. & Rankin, S. M. Neutrophil mobilization and clearance in the bone Competing financial interests: The authors declare no competing financial interests. marrow. Immunology 125, 281–288 (2008). 20. Catlin, S. N., Busque, L., Gale, R. E., Guttorp, P. & Abkowitz, J. L. The replication Reprints and permission information is available online at http://npg.nature.com/ rate of human hematopoietic stem cells in vivo. Blood 117, 4460–4466 (2011). reprintsandpermissions/ 21. Spalding, K. L., Bhardwaj, R. D., Buchholz, B. A., Druid, H. & Frisen, J. How to cite this article: Danial, L. et al. Telomeres shorten at equivalent rates in somatic Retrospective birth dating of cells in humans. Cell 122, 133–143 (2005). 22. Arner, E. et al. Adipocyte turnover: relevance to human adipose tissue tissues of adults. Nat. Commun. 4:1597 doi: 10.1038/ncomms2602 (2013). morphology. Diabetes 59, 105–109 (2010). This work is licensed under a Creative Commons Attribution- 23. Decary, S. et al. Replicative potential and telomere length in human skeletal muscle: implications for satellite cell-mediated gene therapy. Hum. Gene Ther. NonCommercial-ShareAlike 3.0 Unported License. To view a copy of 8, 1429–1438 (1997). this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ 6 NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications & 2013 Macmillan Publishers Limited. All rights reserved. DOI: 10.1038/ncomms2976 Corrigendum: Telomeres shorten at equivalent rates in somatic tissues of adults Lily Daniali, Athanase Benetos, Ezra Susser, Jeremy D. Kark, Carlos Labat, Masayuki Kimura, Kunj K. Desai, Mark Granick & Abraham Aviv Nature Communications 4:1597 doi: 10.1038/ncomms2602 (2010); Published 19 March 2013; Updated 24 July 2013 The original version of this Article contained a typographical error in the spelling of the author Kunj K. Desai, which was incorrectly given as Kunji Desai. This has now been corrected in both the PDF and HTML versions of the Article. NATURE COMMUNICATIONS | 4:1976 | DOI: 10.1038/ncomms2976 | www.nature.com/naturecommunications 1 & 2013 Macmillan Publishers Limited. All rights reserved. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Nature Communications Springer Journals

Telomeres shorten at equivalent rates in somatic tissues of adults

Loading next page...
 
/lp/springer-journals/telomeres-shorten-at-equivalent-rates-in-somatic-tissues-of-adults-mpMsocDpO0

References (80)

Publisher
Springer Journals
Copyright
Copyright © 2013 by The Author(s)
Subject
Science, Humanities and Social Sciences, multidisciplinary; Science, Humanities and Social Sciences, multidisciplinary; Science, multidisciplinary
eISSN
2041-1723
DOI
10.1038/ncomms2602
Publisher site
See Article on Publisher Site

Abstract

ARTICLE Received 3 Aug 2012 | Accepted 14 Feb 2013 | Published 19 Mar 2013 | Updated 24 Jul 2013 DOI: 10.1038/ncomms2602 OPEN Telomeres shorten at equivalent rates in somatic tissues of adults 1 2,3 4,5 6 2,3 7 Lily Daniali , Athanase Benetos , Ezra Susser , Jeremy D. Kark , Carlos Labat , Masayuki Kimura , 1 1 7 Kunj K. Desai , Mark Granick & Abraham Aviv Telomere shortening in somatic tissues largely reflects stem cell replication. Previous human studies of telomere attrition were predominantly conducted on leukocytes. However, findings in leukocytes cannot be generalized to other tissues. Here we measure telomere length in leukocytes, skeletal muscle, skin and subcutaneous fat of 87 adults (aged 19–77 years). Telomeres are longest in muscle and shortest in leukocytes, yet are strongly correlated between tissues. Notably, the rates of telomere shortening are similar in the four tissues. We infer from these findings that differences in telomere length between proliferative (blood and skin) and minimally proliferative tissues (muscle and fat) are established during early life, and that in adulthood, stem cells of the four tissues replicate at a similar rate. Division of Plastic Surgery, Department of Surgery, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 2 3 07103, USA. Geriatric Service, Nancy University Hospital, Nancy 54511, France. Inserm U961, Faculty of Medicine, Universite de Lorraine, Nancy 54500, 4 5 France. Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York 10032, USA. New York State Psychiatric Institute, New York, New York 10032, USA. Epidemiology Unit, The Hebrew University–Hadassah School of Public Health and Community Medicine, Ein Kerem, Jerusalem 91120, Israel. The Center of Human Development and Aging, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103, USA. Correspondence and requests for materials should be addressed to A.A. (email: avivab@umdnj.edu). NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications 1 & 2013 Macmillan Publishers Limited. All rights reserved. ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 elomere length (TL) is equivalent in different somatic hematopoietic system explains the infrequent replication of 1–3 7,16,17,20 tissues of the human fetus and newborn . This hematopoietic stem cells in adults at the top of the Tequivalence at birth is owing in part to the activity of hierarchy in spite of the massive turnover of circulating blood telomerase , which counteracts TL shortening resulting from cell cells at its bottom. It also explains the relatively slow rate of age- 13,14 replication during early intra-uterine growth. During extra- dependent leukocyte TL shortening in adulthood , which uterine life, telomerase activity is largely repressed in somatic largely reflects ‘maintenance’ replicative activity of hematopoietic 5,6 tissues, including in hematopoietic stem cells ; hence TL varies stem cells, that is, any replicative activity that is not related to across somatic tissues in proportion to replicative activity. growth and development. Notably, leukocyte TL, which reflects TL in hematopoietic stem Data are available about leukocyte TL dynamics (TL and its 3,7 cells , is shorter than TLs of minimally proliferative somatic age-dependent attrition), and by inference these data also enable 8,9 tissues . Yet, the available data from human studies point to us to understand much about the replicative kinetics of 7,16,17,20 strong correlations in TL across somatic tissues, that is, hematopoietic stem cells in vivo . But no such individuals with long (or short) TL in one tissue also have long information exists, to our knowledge, for other somatic tissues. (or short) TL in other tissues. This ‘synchrony’ in TL across Based on quantifying C in genomic DNA from somatic tissues, 1,2,8–10 somatic tissues has been observed not only in humans but skeletal muscle (hereafter referred to as muscle) and fat do 11,12 also other mammals, including non-human primates . experience some replication, presumably of stem cells/progenitor 21,22 Previous reports on the age-dependent attrition of TL in cells . In the present study, we examined TL measures and humans are based primarily on studies of leukocytes. These age-dependent TL attrition in four tissues in a cross-sectional studies suggest that the rate of age-dependent leukocyte TL study spanning more than five decades of adult life. Our findings shortening is rapid early in life but slows down during adulthood indicate that during adulthood, age-dependent TL shortening is 13,14 15 in both humans and in non-human primates . Furthermore, similar in all four tissues regardless of their replicative activity. simulations of TL dynamics in granulocytes and leukocytes have This unexpected result provides an important insight with respect been used to gauge the replicative kinetics of hematopoietic stem to stem cell/progenitor cell replicative kinetics and their potential 7,16,17 cells . The findings of such simulations suggest that the rapid links to aging and longevity in humans. leukocyte TL attrition during the first two decades of the human life course reflects the expansion of the hematopoietic stem cell Results and hematopoietic progenitor cell pools. This expansion involves Subject characteristics. Participants consisted of 61 women and both symmetric cell divisions in which a hematopoietic stem cell 26 men (Table 1), 35 Blacks and 52 whites (33 Hispanics and 19 divides into two daughter hematopoietic stem cells, and non-Hispanic whites) with an age range of 19–77 years. Hispanics asymmetric cell divisions in which a hematopoietic stem cell and non-Hispanic whites were grouped as whites for comparison divides into one hematopoietic stem cell and one hematopoietic 18 with Blacks (Table 2), as no differences were observed between progenitor cell . Hispanics and non-Hispanic whites with respect to variables of Growth and development require only a few symmetric interest, including TLs in the four tissue types (leukocytes, replications of hematopoietic stem cells. By contrast, the vast muscle, skin and fat). expansion of the hematopoietic progenitor cell pool requires numerous asymmetric replications of hematopoietic stem cells . In this way, the incrementally larger and more differentiated TLs of the subjects. TL was longest in muscle and shortest in pools and sub-pools of hematopoietic progenitor cells, down the leukocytes (Table 1) (Po0.0001 (paired Wilcoxon signed-rank hematopoietic hierarchy, are able to maintain homeostasis of test) for all comparisons). In univariate analysis, TL was longer in circulating blood cells. During growth and development, women than in men for leukocytes and for muscle (Table 1). In homeostasis must accommodate both the expansion of the addition, Blacks displayed a longer TL than whites in leukocytes hematopoietic system and the staggeringly high rate of turnover and muscle (Table 2). In multivariable analysis that included age, of some blood cells, which persists throughout life. For instance, sex, body mass index and ethnicity/race (Table 3), age explained B100 billion neutrophils are mobilized from the bone marrow of 17.5% of the inter-individual variation in leukocyte TL, 8.2% of adult humans each day . This hierarchical feature of the muscle TL, 10.5% of skin TL and 12.4% of fat TL. Table 1 | Demographic characteristics and TL parameters for the entire cohort and by sex. All Men Women Number 87 26 61 ± ± ± Age (years) 44 14 (19–77) 46 18 (19–77) 44 11 (20–68) Sex (%) 100 30 70 Blacks (%) 40 27 46 Whites (%) 21 35 16 Hispanics (%) 38 38 38 ± ± ± BSA (m ) 2.02 0.31 (1.58–3.30) 2.09 0.36 (1.58–3.30) 1.99 0.29 (1.59–2.75) ± ± ± BMI (kg m)33 9 (18–63) 31 9 (18–62) 34 9 (23–63) ± ± ± Leukocyte TL (kb) 7.02 0.86 (4.52–10.25) 6.77 1.16 (4.52–10.25) 7.13 0.67 (5.89–9.13)* ± ± ± Muscle TL (kb) 8.55 0.94 (5.86–11.53) 8.15 1.13 (5.86–10.35) 8.72 0.79 (7.33–11.53)* ± ± ± Skin TL (kb) 7.29 0.90 (5.03–10.44) 7.16 1.12 (5.03–10.07) 7.35 0.79 (5.63–10.44) ± ± ± Fat TL (kb) 8.18 0.93 (5.17–10.68) 8.10 1.20 (5.17–10.68) 8.21 0.80 (6.48–10.68) BMI, body mass index; BSA, body surface area; TL, telomere length; Whites, non-Hispanic Whites. *Po0.05 women versus men. Values are mean s.d. (min—max) or %. Wilcoxon rank-sum test for difference in medians or w . 2 NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications & 2013 Macmillan Publishers Limited. All rights reserved. NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 ARTICLE Rates of age-dependent TL attrition. Cross-sectional analysis skin¼ 5.03–10.44 kb; fat¼ 5.17–10.68 kb (Table 1). Individuals indicated that the four somatic tissues displayed significant but showed strong correlations of TL between tissues, such that those similar age-dependent TL attritions per year (mean s.e.m.): with long (or short) TL in one tissue typically displayed long (or ± ± ± leukocytes¼ 26 6 bp; muscle¼ 24 7 bp; skin¼ 23 7 bp; and short) TL in other tissues (r¼ 0.72–0.84, Po0.0001; Pearson’s fat¼ 25 7 bp (Fig. 1). Consequently, the average differences (D) correlation) for each possible pairing of tissue types (Fig. 3). The in TL between the four tissues were stable throughout the association of leukocyte TL with the other three tissues was also 5-decade age range (Fig. 2). consistently high (r¼ 0.83–0.84, Po0.0001; Pearson’s correlation) for each pairing irrespective of the proliferative nature of the tissue. Comparisons of TLs across somatic tissues. TLs in all four tis- Discussion sues displayed wide inter-individual variation in the following ranges: leukocytes¼ 4.52–10.25 kb; muscle¼ 5.86–11.53 kb; Three central conclusions can be drawn from this study. First, across more than five decades of adult life, despite different replicative status, leukocytes, muscle, skin and fat displayed Table 2 | Demographic characteristics and TLs parameters similar rates of age-dependent TL attrition. Second, in accord for Blacks and Whites. with this result, differences in TLs between the tissues showed no significant change throughout the age range. We infer, therefore, Blacks Whites that the TL differences between the tissues were largely Number 35 52 established at a younger age, during the first two decades of life. ± ± Age (years) 41.58 12.18 (19.31–67.16) 46.09 14.47 (19.59–77.38) Third, we confirmed observations from previous limited studies Women (%) 80 63 BSA (m ) 2.09±0.29 (1.59–2.75) 1.97±0.33 (1.58–3.30)* that there is an intra-individual synchrony in TL across the ± ± 1–3,8–10 BMI (Kg m)35 8 (23–48) 32 9 (18–63) somatic tissues of humans as evidenced by the strong ± ± Leucocytes TL (kb) 7.25 0.71 (5.89–9.13) 6.87 0.92 (4.52–10.25)* correlations observed between the TLs in all tissue type pairings. ± ± Muscle TL (kb) 8.88 0.91 (6.55–11.53) 8.33 0.90 (5.86–10.38)** ± ± Skin TL (kb) 7.33 0.71 (5.63–8.53) 7.27 1.02 (5.03–10.44) This intra-individual synchrony in TL across somatic tissues is ± ± Fat TL (kb) 8.26 0.81 (6.48–9.61) 8.13 1.00 (5.17–10.68) 11,12 also seen in other mammals . The finding that four somatic tissues, which are characterized BMI, body mass index; BSA, body surface area; TL, telomere length. *Po0.05; **Po0.01 Blacks versus Whites. by vastly differing rates of proliferation, showed similar rates of Values are mean s.d. (min—max) or %. TL attrition across the adult life span was entirely unexpected. A Wilcoxon rank-sum test for difference in medians or w . cross-sectional study of ten individuals, including neonates, found no evidence of TL shortening in muscle across more than eight decades . Similarly, another study, comprising 16 subjects (mean age 25 years) and 26 subjects (mean age 74 years), concluded that Table 3 | Determinants of tissue TL (univariate and there was no evidence of age-dependent muscle TL attrition multivariate analysis). during adulthood . In our much larger, albeit still modestly sized sample population, we used a more accurate method of TL Univariate Multivariate measurement and clearly draw a different conclusion. 2 2 R (%) PR (%) P Longitudinal studies have reported considerable inter-indivi- Leucocyte TL dual variation in the rate of leukocyte TL shortening among Age 17.5 0.0002 17.5 0.0002 25,26 adults . The same presumably applies to TL attrition in other Sex 3.6 0.08 — 0.13 27–29 somatic tissues. Although leukocyte TL is largely heritable , BMI 0.6 0.50 — 0.58 environmental factors may influence its dynamics. For instance, Race/ethnicity 4.8 0.042 — 0.14 30–32 30,31 cigarette smokers , obese persons and those with a Model 17.5 Muscle TL Leukocytes Muscle y = –0.024x + 9.60 Age 11.7 0.001 8.2 0.004 12 y = –0.026x + 8.18 12 R = 0.12; P =0.002 R = 0.17 P =0.00006 Sex 7.9 0.008 4.8 0.027 Men Men BMI 0.9 0.39 — 0.12 10 10 Women Women Race/ethnicity 8.2 0.007 3.8 0.047 Model 22.0 8 8 Skin TL 6 6 Age 12.5 0.0008 10.5 0.002 Sex 1.0 0.35 — 0.36 4 4 0 20406080 100 0 20406080 100 BMI 4.6 0.049 3.9 0.055 Age (years) Age (years) Race/ethnicity 0.1 0.76 — 0.95 Model 15.0 Skin Fat 12 12 y = –0.023x + 8.32 y = –0.025x + 9.27 2 2 R = 0.13; P =0.0008 R = 0.13; P =0.0005 Fat TL 10 Men 10 Men Age 13.3 0.0005 12.4 0.001 Women Women Sex 0.3 0.62 — 0.67 8 8 BMI 5.7 0.03 4.9 0.03 Race/ethnicity 0.5 0.51 — 0.58 6 6 Model 18.1 BMI, body mass index; TL, telomere length. 4 4 0 20 40 60 80 100 0 20 40 60 80 100 The associations of age, sex, BMI (continuous variables) and race/ethnicity (Blacks versus others) with TL were tested in univariate and multivariate models. R represents the contribution Age (years) Age (years) (%) of each of the variables to TL. Only R values of variables that were significantly associated with leukocyte TL in the multivariate analysis are shown. R of the model represents the joint Figure 1 | Correlation between TL and age in various tissues. TL in contribution to TL of the tested variables in the multivariate analysis. leukocytes, muscle, skin and fat is plotted against age. NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications 3 & 2013 Macmillan Publishers Limited. All rights reserved. Telomere length (kb) Telomere length (kb) Telomere length (kb) Telomere length (kb) ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 Leukocytes–muscle Leukocytes–fat Leukocytes–skin 1 1 1 0 0 0 –1 –1 –1 –2 –2 –2 –3 –3 –3 Men y = –0.0025x –1.42 Men y = –0.0014x –1.10 Men y = –0.0028x –0.15 2 2 2 Women R = 0.0046; P = 0.51 Women R = 0.0013; P = 0.73 Women R = 0.0056; P =0.48 –4 –4 –4 0 20 40 60 80 100 0 20 40 60 80 100 0 20 40 60 80 100 Age (years) Age (years) Age (years) Skin–muscle Skin–fat Fat–muscle 1 1 1 0 0 0 –1 –1 –1 –2 –2 –2 –3 –3 –3 Men y = 0.0003x –1.27 Men y = 0.0014x –0.95 y = –0.0012x –0.32 Men 2 2 2 Women R = <0.0001; P = 0.97 Women R = 0.0015; P = 0.71 Women R = 0.0006; P = 0.80 –4 –4 –4 0 20 40 60 80 100 0 20 40 60 80 100 0 20 40 60 80 100 Age (years) Age (years) Age (years) Figure 2 | Differences in TL in tissues are stable. Differences in TL (D) between tissues within the same individuals are plotted against the ages of the donors of the samples. 12 y = 0.77x + 0.45 12 y = 0.77x + 0.72 12 y = 0.79x + 1.27 2 2 2 R = 0.71; P <0.0001 R = 0.69; P <0.0001 R = 0.69; P <0.0001 Men Men Men 10 10 10 Women Women Women 8 8 8 6 6 6 4 4 4 4 6 8 10 12 4 6 8 10 12 4 6 8 10 Muscle telomere length (kb) Fat telomere length (kb) Skin telomere length (kb) 12 12 12 y = 0.69x + 1.41 y = 0.82x + 0.59 y = 0.76x + 1.72 2 2 2 R = 0.51; P <0.0001 R = 0.71;P <0.0001 R = 0.59; P <0.0001 Men Men Men 10 10 10 Women Women Women 8 8 8 6 6 6 4 4 4 46 810 12 46 810 12 46 810 Muscle telomere length (kb) Fat telomere length (kb) Muscle telomere length (kb) Figure 3 | Equivalence in TL between tissues within the same individual. Although the correlations between TLs of the four tissues are strong, the highly proliferative tissues (leukocytes and skin) consistently display shorter telomeres than the minimally proliferative tissues (muscle and fat). 33,34 sedentary lifestyle have typically shown shorter leukocyte assuming that telomere loss per division is the same in all somatic TLs, presumably owing to an increased burden of inflammation, tissues, it seems that during adult life the rates of replicative which might accelerate hematopoietic stem cell divisions, and activity of stem cells are similar in proliferative and minimally oxidative stress, which might augment their telomere shortening proliferative tissues. per replication. Endurance running, in contrast, apparently We propose that the differences in TL between somatic tissues shortens TL in muscle perhaps owing to heightened of adults largely arise from the expansion during growth and proliferation of stem cells/progenitor cells (satellite cells) to development of the stem cell pool through both symmetric stem build/repair muscle tissue . Thus, the rates of TL attrition in cell divisions and more so for the progenitor cell pool, through both proliferative and minimally proliferative tissues during adult asymmetric stem cell divisions. Theoretically, o5 rounds of life may be modified by a variety of factors. This may account in symmetric divisions of the entire hematopoietic stem cell pool are part for the large inter-individual variation of D in TLs between necessary to expand the compartment in tandem with an increase tissues within individuals (Fig. 2). Still, as age-dependent TL in body weight from 3 kg of birth weight to 80 kg adult weight, attrition ultimately reflects division in the stem cell pool, and that is, 3–6 kg (first round); 6–12 kg (second round); 12–24 kg 4 NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications & 2013 Macmillan Publishers Limited. All rights reserved. Δ Telomere length (kb) Δ Telomere length (kb) Skin telomere length (kb) Leukocyte telomere length (kb) Δ Telomere length (kb) Δ Telomere length (kb) Skin telomere length (kb) Leukocyte telomere length (kb) Δ Telomere length (kb) Δ Telomere length (kb) Fat telomere length (kb) Leukocyte telomere length (kb) NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 ARTICLE (third round); 24–48 kg (fourth round); and 48–96 kg (fifth transplant , with the rebuilding of both the hematopoietic stem round) . Therefore, to accommodate growth, the impact of the cell pool and also the hematopoietic progenitor cell pool. expansion of the hematopoietic stem cell pool on leukocyte TL is Nevertheless, the strong correlations noted between all pairings relatively small. This is also likely to be the case for TL dynamics of tissue types, irrespective of their replicative potential, suggest 1,2 in other somatic tissues, including minimally proliferative ones. that the initial equivalence of TL in utero and at birth continues In contrast, numerous asymmetric divisions of hematopoietic to dominate the TL phenotypic landscape across the lifespan, and stem cells are required during growth to build the large that accelerated stem cell division during growth and development hematopoietic progenitor cell pool in order to maintain the after birth exerts a more modest effect that reduces this numbers of circulating blood cells, a subset of which has an equivalence. Thus, the main contributors to TL and its similarity enormous turnover . Consequently, as illustrated in Fig. 4, in individuals are primarily prenatal, followed by growth in leukocyte TL undergoes considerable shortening during early childhood and adolescence, with less influence in adulthood. 7,13–15 life . The same might apply, although to a lesser extent, to We acknowledge a number of shortcomings of this study. other highly replicative somatic tissues, such as skin. In contrast, First, our study was cross-sectional in design; we used tissues the expansions of progenitor cell pools during growth and obtained during elective surgical procedures from individuals development in minimally proliferative tissues, such as muscle of different ages to compute TL dynamics. Ideally, measurement and fat, are probably limited. The sizes of these progenitor cell of age-dependent TL attrition should be performed longitudinally pools may be calibrated to accommodate only small cell turnover in the same individuals, but this was simply not feasible. Second, rates in adulthood. Accordingly, early in life, TLs of muscle and the samples of muscle, skin and fat were obtained from different other minimally proliferative tissues undergo substantially less sites, but we doubt that body region exerted any influence on the findings. We found no evidence that surgical site (head and neck, attrition than leukocyte TL (Fig. 4). The need to establish a huge thorax, abdomen, upper extremities and lower extremities) hematopoietic progenitor cell pool may be the reason that bone impacted TL without and with adjustment for age. Third, marrow failure is the first catastrophic manifestation arising from leukocyte TL is derived from circulating cells, which are major mutations in telomere maintenance genes . It also explains partitioned from the less mature hematopoietic cells in the bone the rapid leukocyte TL shortening post hematopoietic stem cell marrow. In contrast, TLs in solid tissues reflect TL of fully differentiated cells as well as resident stem cells/progenitor cells. However, we doubt that TLs of these precursor cells exert an appreciable influence on the mean TLs in muscle and other Hematopoietic cells minimally proliferative tissues, because, as discussed above, the size of the stem cell/progenitor cell pools in these tissues is very small. Furthermore, although we examined several fold more patients than in previous studies, our sample size remains modest and requires extension. In conclusion, in adults, both highly proliferative and minimally proliferative tissues appear to display similar age- Skeletal muscle dependent telomere attrition. Moreover, in this study population, the average gap in TLs between the proliferative and minimally proliferative tissues was essentially constant between the ages of Age 19–77 years, suggesting that the first 20 years of life is a crucial time period for establishing this difference. As TL dynamics largely reflect stem cell kinetics, we infer that stem cell division rates for maintenance might be similar in the somatic tissues we Skeletal muscle examined, regardless of their proliferative status. Making clinical use of TL in predicting future health risks will depend to a large extent on understanding the underlying inter-individual varia- tions in TL at birth and its attrition during human growth and development. Hematopoietic cells Methods Recruitment of study participants. Inpatients and outpatients scheduled for general, plastic and vascular surgery at the University Hospital of the University of Age Medicine and Dentistry of New Jersey were approached by the study coordinator for participation in this investigation. These also included patients undergoing Figure 4 | Model of progenitor cell pool dynamics and in different surgical procedures to remove cancer with no evidence of metastasis. This research tissues. Upper panel: during growth (grey shade), the progenitor cell pool was approved by the Institutional Review Board (IRB) of the University of Med- in the hematopoietic system undergoes massive expansion through icine and Dentistry of New Jersey, New Jersey Medical School. All participants signed a written informed consent approved by the IRB. Participants were asked to asymmetric replication of hematopoietic stem cells. In this way, the system donate blood (from the intravenous line or phlebotomy) and B50–100 mg spe- can accommodate the tremendous turnover in peripheral blood cells. In cimens of skin, subcutaneous fat and skeletal muscle in the surgical field. If the contrast, during growth, the progenitor cell pool in skeletal muscle attending surgeon indicated the study coordinator that one of the tissue types could undergoes a modest expansion through replication of muscle stem cells, as not be sampled during the surgery, the potential study subject was not approached for enrolment. Similarly, all subjects who had received therapeutic irradiation to the turnover of skeletal muscle cells is small. Lower panel: reflecting the the surgical site and those with a history of immunosuppression secondary to a expansions of the progenitor cell pools in the respective systems, TL medical condition or of chemotherapy for cancer treatment were not enroled. undergoes rapid attrition in the hematopoietic system but only modest Three subjects were excluded owing to HIV infection and sickle cell disease. attrition in skeletal muscle. The slow and parallel attritions of TLs in stem cells, as expressed in leukocyte TL and in skeletal muscle TL during adult Measurements of TL. DNA integrity was evaluated by resolving samples on 1% life, are the outcome of ’maintenance’ replicative activities of stem cells/ (wt/vol) agarose gel. Samples were digested with restriction enzymes Hinf I (10 U) progenitor cells in these systems. and Rsa I (10 U; Roche). Digested DNA samples and DNA ladders were resolved NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications 5 & 2013 Macmillan Publishers Limited. All rights reserved. Telomere length Progenitor cell pool ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms2602 on 0.5% agarose gels. After 16 h, the DNA was depurinated for 15 min in 0.25 N 24. Ponsot, E., Lexell, J. & Kadi, F. Skeletal muscle telomere length is not impaired HCl, denatured 30 min in 0.5 M NaOH/1.5 mol l NaCl and neutralized for in healthy physically active old women and men. Muscle Nerve 37, 467–472 30 min in 0.5 mol l Tris, pH 8/1.5 M NaCl. The DNA was transferred for 1 h to a (2008). positively charged nylon membrane (Roche) using a vacuum blotter (Boeckel 25. Chen, W. et al. Longitudinal versus cross-sectional evaluations of leukocyte Scientific, Feasterville, PA). Membranes were hybridized at 65 C with the DIG- telomere length dynamics: age-dependent telomere shortening is the rule. labelled telomeric probe overnight as previously described . The DIG-labelled J. Gerontol. A Biol. Sci. Med. Sci. 66, 312–319 (2011). probe was detected by the DIG luminescent (Roche) and exposed on X-ray film. 26. Kark, J. D., Goldberger, N., Kimura, M., Sinnreich, R. & Aviv, A. Energy intake The inter-assay coefficient of variation of the TL measurements was 1.8%. and leukocyte telomere length in young adults. Am. J. Clin. Nutr. 95, 479–487 (2012). 27. Slagboom, P. E., Droog, S. & Boomsma, D. I. Genetic determination of telomere Statistical analysis. Descriptive values are expressed as mean s.d., number of size in humans: a twin study of three age groups. Am. J. Hum. Genet. 55, patients and percentages. The population was divided according to sex or ethnicity/ 876–882 (1994). race, and compared using the Wilcoxon rank-sum test or the w test. Comparisons 28. Andrew, T. et al. Mapping genetic loci that determine leukocyte telomere of TL among different tissues were performed using a paired Wilcoxon signed-rank length in a large sample of unselected, female sib-paternal age influencers. Am. test. A P-value o0.05 was regarded as statistically significant. Relationships J. Hum. Genet. 78, 480–486 (2006). between TL and age in the four tissues (by pairs) were determined using Pearson’s 29. Jeanclos, E. et al. Telomere length inversely correlates with pulse pressure and is correlation coefficients. The effects of age, sex, race/ethnicity and body mass index highly familial. Hypertension 36, 195–200 (2000). were evaluated in a multiple regression analysis by including the variables asso- 30. Strandberg, T. E. et al. Association of telomere length in older men with ciated with TL that had a P-value o0.10 in the univariate analysis. Statistical analyses were carried out using the NCSS 2004 statistical software package. mortality and midlife body mass index and smoking. J. Gerontol. A Biol. Sci. Med. Sci. 66, 815–820 (2011). 31. Valdes, A. M. et al. Obesity, cigarette smoking, and telomere length in women. References Lancet 366, 662–664 (2005). 1. Youngren, K. et al. Synchrony in telomere length of the human fetus. Hum. 32. Nawrot, T. S., Staessen, J. A., Gardner, J. P. & Aviv, A. Telomere length and Genet. 102, 640–643 (1998). possible link to X chromosome. Lancet 363, 507–510 (2004). 2. Okuda, K. et al. Telomere length in the newborn. Pediatr. Res. 52, 377–381 (2002). 33. Cherkas, L. F. et al. The association between physical activity in leisure time and 3. Kimura, M. et al. Synchrony of telomere length among hematopoietic cells. leukocyte telomere length. Arch. Intern. Med. 168, 154–158 (2008). Exp. Hematol. 38, 854–859 (2010). 34. LaRocca, T. J., Seals, D. R. & Pierce, G. L. Leukocyte telomere length is 4. Blackburn, E. H. Telomeres and telomerase: their mechanisms of action and the preserved with aging in endurance exercise-trained adults and related to effects of altering their functions. FEBS Lett. 579, 859–862 (2005). maximal aerobic capacity. Mech. Ageing Dev. 131, 165–167 (2010). 5. Yui, J., Chiu, C. P. & Lansdorp., P. M. Telomerase activity in candidate stem 35. Rae, D. E., Vignaud, A., Butler-Browne, G. S., Thornell, L. E. & Sinclair-Smith, cells from fetal liver and adult bone marrow. Blood 91, 3255–3262 (1998). C. Muscle telomere length in healthy, experienced, endurance runners. Eur. J. 6. Morrison, S. J., Prowse, K. R., Ho., P. & Weissman, I. L. Telomerase activity Appl. Physiol. 109, 323–330 (2010). in hematopoietic cells is associated with self-renewal potential. Immunity 5, 36. Calado, R. T. & Young, N. S. Telomere diseases. N. Engl. J. Med. 361, 207–521 (1996). 2353–2365 (2009). 7. Sidorov, I., Kimura, M., Yashin, A. & Aviv, A. Leukocyte telomere dynamics 37. Gadalla, S. M. & Savage, S. A. Telomere biology in hematopoiesis and stem cell and human hematopoietic stem cell kinetics during somatic growth. Exp. transplantation. Blood Rev. 25, 261–269 (2011). Hematol. 37, 514–524 (2009). 38. Kimura, M. et al. Measurement of telomere length by the Southern blot 8. Granick, M. et al. Telomere dynamics in keloids. Eplasty 11, e15 (2011). analysis of terminal restriction fragment lengths. Nat. Protoc. 5, 1596–1607 9. Gardner, J. P. et al. Telomere dynamics in macaques and humans. J. Gerontol. (2010). A Biol. Sci. Med. Sci. 62, 367–374 (2007). 10. Friedrich, U. et al. Telomere length in different tissues of elderly patients. Mech. Acknowledgements Ageing Dev. 119, 89–99 (2000). This work has been supported by NIH grants AG16592, AG030678, HD071180 11. Benetos, A. et al. A model of canine leukocyte telomere dynamics. Aging Cell MH059114, the US-Israel Binational Science Foundation, the Israel Science Foundation, 10, 991–995 (2011). the Fondation pour la Recherche Medicale (FRM DCV- 20070409250), the Agence 12. Smith, Jr D. L. et al. Telomere dynamics in rhesus monkeys: no apparent effect Nationale de la Recherche (ANR 09-GENO-010-01) and the Plan Pluri-Formation of caloric restriction. J. Gerontol. A Biol. Sci. Med. Sci. 66, 1163–1168 (2011). (French Ministry of Research). 13. Aubert, G., Baerlocher, G. M., Vulto, I., Poon, S. S. & Lansdorp, P. M. Collapse of telomere homeostasis in hematopoietic cells caused by heterozygous mutations in telomerase genes. Plos Genet. 8, e1002696 (2012). Author contributions 14. Frenck, R. W., Blackburn, E. H. & Shannon, K. M. The rate of telomere L.D. participated in study design, sample and data collections and writing the manu- sequence loss in human leukocytes varies with age. Proc. Natl Acad. Sci. USA script. A.B. participated in study design, analysis of data and writing the manuscript. 95, 5607–5610 (1998). E.S. participated in data analysis and writing the manuscript. J.D.K. participated in data 15. Baerlocher, G. M., Rice, K., Vulto, I. & Lansdorp, P. M. Longitudinal data on analysis and writing the manuscript. C.L. oversaw data analysis and participated in telomere length in leukocytes from newborn baboons support a marked drop in writing the manuscript. M.K. oversaw TL measurements. K.D. participated in sample stem cell turnover around 1 year of age. Aging Cell 6, 121–123 (2007). collections. M.G. participated in study design and oversaw sample collections. A.A. 16. Shepherd, B. E., Guttorp, P., Lansdorp, P. M. & Abkowitz, J. L. Estimating conceived the study and its design, oversaw the entire project and participated in writing human hematopoietic stem cell kinetics using granulocyte telomere lengths. the manuscript. Exp. Hematol. 32, 1040–1050 (2004). 17. Shepherd, B. E. et al. Hematopoietic stem-cell behavior in nonhuman primates. Additional information Blood 110, 1806–1813 (2007). Supplementary Information accompanies this paper at http://www.nature.com/ 18. Morrison, S. J. & Kimble, J. Asymmetric and symmetric stem-cell divisions in naturecommunications development and cancer. Nature 441, 1068–1074 (2006). 19. Furze, R. C. & Rankin, S. M. Neutrophil mobilization and clearance in the bone Competing financial interests: The authors declare no competing financial interests. marrow. Immunology 125, 281–288 (2008). 20. Catlin, S. N., Busque, L., Gale, R. E., Guttorp, P. & Abkowitz, J. L. The replication Reprints and permission information is available online at http://npg.nature.com/ rate of human hematopoietic stem cells in vivo. Blood 117, 4460–4466 (2011). reprintsandpermissions/ 21. Spalding, K. L., Bhardwaj, R. D., Buchholz, B. A., Druid, H. & Frisen, J. How to cite this article: Danial, L. et al. Telomeres shorten at equivalent rates in somatic Retrospective birth dating of cells in humans. Cell 122, 133–143 (2005). 22. Arner, E. et al. Adipocyte turnover: relevance to human adipose tissue tissues of adults. Nat. Commun. 4:1597 doi: 10.1038/ncomms2602 (2013). morphology. Diabetes 59, 105–109 (2010). This work is licensed under a Creative Commons Attribution- 23. Decary, S. et al. Replicative potential and telomere length in human skeletal muscle: implications for satellite cell-mediated gene therapy. Hum. Gene Ther. NonCommercial-ShareAlike 3.0 Unported License. To view a copy of 8, 1429–1438 (1997). this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ 6 NATURE COMMUNICATIONS | 4:1597 | DOI: 10.1038/ncomms2602 | www.nature.com/naturecommunications & 2013 Macmillan Publishers Limited. All rights reserved. DOI: 10.1038/ncomms2976 Corrigendum: Telomeres shorten at equivalent rates in somatic tissues of adults Lily Daniali, Athanase Benetos, Ezra Susser, Jeremy D. Kark, Carlos Labat, Masayuki Kimura, Kunj K. Desai, Mark Granick & Abraham Aviv Nature Communications 4:1597 doi: 10.1038/ncomms2602 (2010); Published 19 March 2013; Updated 24 July 2013 The original version of this Article contained a typographical error in the spelling of the author Kunj K. Desai, which was incorrectly given as Kunji Desai. This has now been corrected in both the PDF and HTML versions of the Article. NATURE COMMUNICATIONS | 4:1976 | DOI: 10.1038/ncomms2976 | www.nature.com/naturecommunications 1 & 2013 Macmillan Publishers Limited. All rights reserved.

Journal

Nature CommunicationsSpringer Journals

Published: Mar 19, 2013

There are no references for this article.