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1.
In order to analyse telomere length in subsets of human peripheral blood lymphocytes and monocytes, we modified a recently developed multicolor flow- fluorescent in situ hybridization (FISH) methodology that combines flow-FISH and antibody staining for cell surface antigens. We analysed telomere length of peripheral blood mononuclear cells in a group of 22 patients with systemic lupus erythematosus (SLE) and 20 age-matched healthy donors. We found that neither CD4+, CD8+, CD19+ cells nor CD14+ monocytes have significantly shorter telomeres compared with their healthy counterparts. On the basis of these findings, we then used monocyte telomere length as internal reference in order to control for intra-individual variability in telomere length. By using this approach, we could demonstrate significant telomere shortening in all three lymphocyte subsets (in all cases P < 0.05) compared with monocytes. However, these differences did not vary significantly between SLE patients and controls. In summary, telomere lengths in subpopulations of hematopoietic cells can be monitored in patients with SLE using multicolor flow-FISH. While confirming data by other groups on telomere length in lymphocyte subpopulations, our data argue against an increased proliferation rate of peripheral blood monocytes reflected by accelerated telomere shortening in patients with SLE.  相似文献   

2.
Telomere length indicates the replicative history of cells, serving as a molecular measure of the replicative potential remaining in cells. To investigate telomere length changes in hematopoietic stem cells, patients undergoing hematopoietic stem cell transplantation (HSCT) were evaluated. Fifteen patients after allogeneic bone marrow transplantation (allo-BMT group), seven patients after autologous peripheral blood stem cell transplantation (auto-PBSCT group), and 39 healthy controls were studied. Telomere length was measured in peripheral mononuclear cells by Southern blot hybridization. There was no significant difference between the allo-BMT and the auto-PBSCT groups. In the allo-BMT group, the mean telomere length of recipients was 2.01 kb shorter than that of their donors (P = 0. 008), and was 1.59 kb shorter than that of age-matched putative normal controls (P = 0.002). Telomere shortening in the allo-BMT group was equivalent to 41.4 years of aging in the donors, and to 52. 4 years of aging in the normal controls. The mean telomere length in the auto-PBSCT group was 2.36 kb shorter than that of the age-matched putative controls (P = 0.043), which was equivalent to 61.5 years of aging in normal controls. The extent of telomere shortening in the allo-BMT group showed a trend to negative correlation with the number of mononuclear cells infused. These findings suggest that hematopoietic stem cells after HSCT lose telomere length and these shortened telomeres may result in a higher incidence of clonal disorders later in life.  相似文献   

3.

Objective

Patients with systemic lupus erythematosus (SLE) have a higher rate of premature death compared to the general population, suggesting a phenotype of premature senescence in SLE. Telomere length can be used to assess overall biologic aging. This study was undertaken to address the hypothesis that patients with SLE have reduced telomere length.

Methods

Telomere length was measured cross‐sectionally in whole blood from SLE patients and age‐matched healthy female controls, using real‐time quantitative polymerase chain reaction. SLE‐related and cardiovascular risk factors were assessed.

Results

We compared telomere length in 63 SLE patients and 63 matched controls with a median age of 50.8 years (interquartile range [IQR] 37–59 years) and 49.9 years (IQR 32–60 years), respectively. The median relative telomere length in SLE patients was 0.97 (IQR 0.47–1.57), compared to 1.53 (IQR 0.82–2.29) in controls (P = 0.0008). We then extended our cohort to measure telomere length in 164 SLE patients. Shorter telomere length was associated with Ro antibodies (β ± SE −0.36 ± 0.16; P = 0.023), and longer telomere length was associated with steroid therapy (0.29 ± 0.14; P = 0.046). We also noted an association of longer telomere length with increasing body mass index (β ± SE 0.07 ± 0.01; P < 0.0001) and tobacco smoking (0.64 ± 0.26; P = 0.016), as well as with the presence of carotid plaque (0.203 ± 0.177; P = 0.032).

Conclusion

Telomere length is shortened in SLE patients compared to controls and does not appear to be a reflection of disease activity or immune cell turnover. Subsets of patients such as those positive for Ro antibodies may be particularly susceptible to premature biologic aging. The predictive value of telomere length as a biomarker of future risk of damage/mortality in SLE requires longitudinal evaluation.
  相似文献   

4.
Telomeres are the repeated sequences at the chromosome ends which undergo shortening with cell division. The telomere shortening of the peripheral leukocytes is also facilitated by enhanced oxidative stress in various kinds of disease including ischemic heart disease, diabetes mellitus, apoplexy, and Alzheimer's disease. Telomere shortening in Parkinson's disease (PD) has not yet been reported. The pathogenesis for PD is also regarded to be associated with oxidative stress. We investigated 28 Japanese male PD patients ages 47-69. Although we could not find a statistical difference in the mean telomere length of peripheral leukocytes between the PD patients and the control participants, we found the mean telomere lengths to be shorter than 5 kb in only the PD patients and a significant PD-associated decrease in the telomeres with a length ranging from 23.1 to 9.4 kb in the patients in their 50s and 60s. These observations suggest that telomere shortening is accelerated in PD patients in comparison to the normal population.  相似文献   

5.
We investigated telomere (terminal restriction fragment [TRF]) length in 111 patients with sarcoidosis regarding both the mean TRF length and the telomere length distribution. A significant decrease was observed in the mean TRF length in sarcoidosis patients in comparison to the age-matched controls, whereas a decreased telomere length was only associated with age in men. The mean TRF shortening seemed to be accelerated in men in their 30s and 50s and in women in their 40s and 50s. We also found a significant decrease with age of telomeres with lengths of 9.4-6.6 kb in men and women in their 20s and an increase of telomeres with lengths of 4.4-2.3 kb in men and women in their 20s and in men in their 50s in sarcoidosis patients versus in the controls who were in their 20s and 50s. These findings suggest the occurrence of age-advanced changes in telomere length in patients with sarcoidosis, regardless of the patient age at the onset of sarcoidosis.  相似文献   

6.
OBJECTIVES: Ulcerative colitis (UC) is characterized by damage to the intestinal epithelium and connective tissue. The causes of this damage could include changes in the ability of colonic fibroblasts to heal wounds and maintain epithelial cell proliferation. Telomeres shorten with each cell division and eventually signal senescence. The aim of this study is to investigate whether the impaired function of rectal fibroblasts in UC is due to accelerated telomere shortening, oxidative stress and premature senescence. METHODS: We isolated rectal fibroblasts from eight UC patients and nine non-colitis controls, and recorded their in-vitro lifespans. Telomere lengths and superoxide dismutase mRNA expression were also measured by real-time polymerase chain reaction and peroxide levels were measured by flow cytometry. RESULTS: The fibroblast lifespan decreased as patient age increased (R2=0.68, P=0.003) in control patients, but this relationship was absent in UC fibroblasts. We identified a group of patients who were diagnosed later in life than a second group (59 versus 35 years, P=0.002). Fibroblasts from these late-onset UC patients underwent significantly more population doublings before senescence than age-matched controls (25 versus 15, P=0.02). Slower in-vitro telomere shortening rates (32 versus 344, P=0.006) and trends towards longer telomeres at explant were also observed in late-onset UC fibroblasts. Peroxide levels correlated positively with telomere shortening rate (r=0.581, P=0.078). CONCLUSIONS: Some UC-predisposed individuals may have more efficient antioxidant systems that protect the telomeres from oxidative damage. This may allow their rectal fibroblasts to live longer, function better and thus delay the onset of the disease until later life.  相似文献   

7.
Telomere shortening represents an established mechanism connecting aging and cancer development. We sequentially analyzed telomere length (TL) of 49 acute myeloid leukemia (AML) patients at diagnosis (n = 24), once they achieved complete cytological remission (CCR) and/or during refractory disease or relapse and after 1-year follow-up, with all patients having at least two sequential samples. TL was analyzed by monochrome multiplex quantitative polymerase chain reaction. We have observed substantially shortened TL in the cells of patients at diagnosis compared to age-adjusted controls. In patients reaching CCR after chemotherapy, telomere shortening was less pronounced than in persistence or relapse but still significantly shortened compared to controls. We estimate patients harboring approximately 20 years of premature telomere loss compared to healthy aged-matched subjects at the time of AML onset. Our data indicate a pre-existing telomere deficit in non-clonal hematopoiesis of AML patients providing a link between age and AML development.  相似文献   

8.
Telomere shortening occurs in Asian Indian Type 2 diabetic patients.   总被引:2,自引:0,他引:2  
AIM: Telomere shortening has been reported in several diseases including atherosclerosis and Type 1 diabetes. Asian Indians have an increased predilection for Type 2 diabetes and premature coronary artery disease. The aim of this study was to determine whether telomeric shortening occurs in Asian Indian Type 2 diabetic patients. METHODS: Using Southern-blot analysis we determined mean terminal restriction fragment (TRF) length, a measure of average telomere size, in leucocyte DNA. Type 2 diabetic patients without any diabetes-related complications (n = 40) and age- and sex-matched control non-diabetic subjects (n = 40) were selected from the Chennai Urban Rural Epidemiology Study (CURES). Plasma level of malondialdehyde (MDA), a marker of lipid peroxidation, was measured by TBARS (thiobarbituric acid reactive substances) using a fluorescence method. RESULTS: Mean (+/- SE) TRF lengths of the Type 2 diabetic patients (6.01 +/- 0.2 kb) were significantly shorter than those of the control subjects (9.11 +/- 0.6 kb) (P = 0.0001). Among the biochemical parameters, only levels of TBARS showed a negative correlation with shortened telomeres in the diabetic subjects (r = -0.36; P = 0.02). However, telomere lengths were negatively correlated with insulin resistance (HOMA-IR) (r = -0.4; P = 0.01) and age (r = -0.3; P = 0.058) and positively correlated with HDL levels (r = 0.4; P = 0.01) in the control subjects. Multiple linear regression (MLR) analysis revealed diabetes to be significantly (P < 0.0001) associated with shortening of TRF lengths. CONCLUSIONS: Telomere shortening occurs in Asian Indian Type 2 diabetic patients.  相似文献   

9.
OBJECTIVE: To evaluate the clinical significance of telomerase activity and telomere length in T and B lymphocytes from patients with systemic lupus erythematosus (SLE). METHODS: CD3+ (T cell) and CD19+ (B cell) lymphocytes were isolated from the peripheral blood of SLE patients and healthy controls by means of magnetic bead-coupled antibodies. SLE patients were classified as active or inactive cases according to the SLE Disease Activity Index (SLEDAI). Telomere activity of lymphocytes was measured by telomeric-repeat amplification protocol. Telomere length was measured by flow cytometry-fluorescence in situ hybridization. RESULTS: T cell telomerase activity was significantly higher in patients with both active and inactive SLE than in controls, but was lower than B cell telomerase activity in patients with active SLE, and was not correlated with SLEDAI results. B cell telomerase activity was only significantly higher than in controls in patients with active SLE, and was strongly correlated with SLEDAI. Four laboratory results, anti-dsDNA antibody titer, IgG level, C3 level, and CH50 level, were correlated with B cell telomerase activity. Telomere length in T cells was significantly shorter than in controls. In contrast, the telomere length in B cells did not differ significantly from controls. CONCLUSION: In patients with SLE, many T cells divide continuously. Their telomerase activity was higher than that in control T cells, but not so high as to prevent telomere shortening. In contrast, B cells do not divide abnormally in the inactive phase of SLE, but divide rapidly in the active phase.  相似文献   

10.
Telomere shortening has been documented in the blood cells of recipients of allogeneic bone marrow transplants compared with their donors. Allogeneic peripheral blood progenitor cells (PBPCs) have been increasingly used as an alternative to bone marrow. Their advantages include earlier engraftment and immune reconstitution following transplantation. We have measured telomere length of neutrophils and T cells in fully engrafted recipients of allogeneic bone marrow (n = 19) and allogeneic PBPC (n = 17) and also measured sequential telomere length in four patients after transplantation. Overall, significant telomere shortening occurred in recipients in neutrophils (0.3 kb, P < 0.001) and T cells (0.2 kb, P = 0.045). The data demonstrate that first, the degree of shortening was the same for BM and PBPC transplants and was not related to the time taken to engraft neutrophils and platelets and second, telomere shortening occurs in the first year post transplant without further shortening during the period of observation. These data suggest that the superiority of engraftment seen in PBPC transplants is independent of telomere shortening and other mechanisms such as homing or seeding may be more important.  相似文献   

11.
Multidrug resistance-associated proteins (MRPs, ATP binding cassette sub-family C), P-glycoprotein (P-gp) and ATP binding cassette (ABC) sub-family G member 2 (ABCG2) are important drug efflux pumps emerging after long-term medications. We intended to detect whether these molecules are expressed in immune-related cells of patients with systemic lupus erythematosus (SLE) on long-term immunosuppressants.METHODS:Mono nuclear cells (MNC) and polymorphonuclear neutrophils (PMN) were isolated from healthy volunteers and SLE patients. The MPR-mediated transport activity of these cells was measured by using carboxy-2',7'-dichlorofluorescein diacetate (CFDA) efflux assay. P-gp-mediated transport activity of cells was detected by rhodamine 123 efflux assay. ABCG2-mediated transport assay was evaluated by mitoxantrone efflux assay. The intracellular expression of MRP1, MRP2, and MRP3 molecules in MNC was detected by flow cytometry. The results were compared between MNC and PMN derived from normal and SLE groups.RESULTS:The specific dye-efflux function of MRPs in SLE-MNC is significantly higher than normal MNC. However, the expression of MRP1, MRP2, and MRP3 molecules in SLE-MNC was not different from normal MNC. We also noted that only the duration of corticosteroid treatment in different clinical/laboratory parameters was significantly correlated with the increased activity of MRPs in SLE-MNC.CONCLUSIONS:These results suggest that increased activity of MRPs in SLE-MNC is elicited by long-term corticosteroid therapy.  相似文献   

12.
Chronic myeloid leukemia (CML) is a clonal, multilineage myeloproliferative disorder characterized by the Philadelphia chromosome (Ph) and a marked expansion of myeloid cells. Previous studies have indicated that the telomere length in blood cells may indicate their replicative history. However, the large variation in telomere length between individuals complicates the use of this parameter in CML and other hematologic disorders. To circumvent this problem, we compared the telomere length in peripheral blood or bone marrow cells with purified normal (Ph(-)) T lymphocytes from the same CML patient using fluorescence in situ hybridization and flow cytometry. Overall telomere fluorescence was significantly reduced in Ph(+) cells from patients with CML compared to blood leukocytes from normal individuals (P < 0.001) or normal (Ph(-)) T lymphocytes from the same individuals (n = 51, P < 0.001). Cells from patients in accelerated phase or blast phase (AP/BP) showed significantly shorter average telomere length than cells from patients in chronic phase (CP, P = 0.02) or cytogenetic remission (CR, P = 0.03). Patients in CP who subsequently developed BP within 2 years had significantly shorter telomeres than those who did not develop BP for at least 2 years (P < 0.05). Accelerated replication-dependent telomere shortening in Ph(+ )versus Ph(-) leukocytes supports previous evidence that Ph(+) stem cells cycle more actively than their counterparts in normal individuals. Our data further suggest that telomere shortening may serve as a surrogate marker of disease progression in patients with CP CML, supporting a mechanistic link between CML stem cell turnover, genetic instability, and malignant evolution in this disease. (Blood. 2000;95:1883-1890) (Blood. 2000;95:1883-1890)  相似文献   

13.
Telomere length of peripheral blood mononuclear cells (PBMCs) from 23 autologous HSCT patients ranging from 4 to 61 years old, and 46 allogeneic HSCT recipients from 6 to 52 years old were studied to confirm whether excessive shortening of telomeres is associated with HSCT. After autologous HSCT, telomere length of PBMCs ranged from 6.8 to 12.0 kb. The comparison between transplanted PBMCs and PBMCs after autologous HSCT showed shortening by up to 1.9 kb (mean +/- s.d.: 0.64 +/- 0.50 kb). There was a difference between autologous HSCT patients and normal volunteers in the slopes of regression lines. After allogeneic HSCT, telomere length of PBMCs ranged from 6.8 to 12.0 kb. Telomeres of recipients were up to 2.1 kb (0.60 +/- 0.468 kb) shorter than those of donors. The slope of regression lines for allogeneic HSCT patients and normal volunteers were parallel. Although all patients were transplanted with more than 2.0 x 10(8) cells/kg, telomere length did not correlate with the number of transplanted cells. There was no significant correlation between telomere length and recovery of hematological parameters. However, three patients with an average telomere length of 6.8 kb after HSCT took a longer period to reach the normal hematological state. Taken together, these data suggest that most HSCTs are performed within the biological safety range of telomeres, while the patients who have telomeres shorter than 7.0 kb after HSCT should be observed carefully for long-term hematopoiesis and the occurrence of hematopoietic disorders.  相似文献   

14.
Telomeres are regions of repetitive DNA at the end of eukaryotic chromosomes, which prevent chromosomal instability. Telomere shortening is linked to age-related disease including Alzheimer's disease (AD) and has been reported to be reduced in leukocytes of AD patients. The aim of the present study was to measure telomere length in monocytes of patients with AD or mild cognitive impairment (MCI) compared to healthy subjects. Our data show significant shorter telomere length in AD patients (6.6±0.2kb; p=0.05) compared to controls (7.3±0.2kb). Telomere length of MCI patients did not differ compared to healthy subjects (7.0±0.2kb). We observe a strong correlation between telomere length and age (p=0.01, r=-0.38), but no association between telomere length and Mini-Mental State Examination score. In conclusion, the telomere length is age-dependent in monocytes and decreased in AD patients, which could mean that the AD pathology may contribute to telomere length shortening. The high variability of telomere lengths in individuals suggests that it will not be useful as a general biomarker for AD. However, it could become a biomarker in personalized long-term monitoring of an individuals' health.  相似文献   

15.
We studied telomere length in the peripheral blood leukocyte samples of a large group of patients with chronic myelogenous leukemia (CML) by Southern blot hybridization using the (TTAGGG)4 probe. The average telomere length expressed as the peak telomere repeat array (TRA) of the peripheral blood samples obtained from a group of 34 healthy age-matched controls ranged between 7.6 and 10.0 kb and the mean peak TRA was 8.7 kb. Forty-one patients in the chronic phase of CML were studied; 32/41 (78%) showed telomere reduction (<7.6 kb) relative to age-matched controls and the mean peak TRA was 6.4 kb (range 4.0-10.6 kb). Serial samples were analysed from 12 patients at both chronic phase and during disease progression. The leukocyte DNA of all 12 patients in accelerated phase and/or blast crisis showed telomere reduction relative to age-matched controls and the mean peak TRA was 4.1 kb (range 3.0-5.4 kb). The peak TRA in the accelerated or blast phase was reduced compared with the corresponding paired sample in the chronic phase in all cases studied. These data show that a marked reduction in telomere length is associated with disease progression in CML.  相似文献   

16.
Telomeres serve as a mitotic clock and biological marker of senescence. Diabetes mellitus (DM) is associated with damage to target organs and premature aging. We assessed the effect of glycemic control on telomere dynamics in arterial cells of 58 patients undergoing coronary artery bypass and in mononuclear blood cells of other diabetic (32 type I and 47 type II) patients comparing well controlled to uncontrolled patients. All were compared to age-dependent curve of healthy controls. Telomeres were significantly shorter in the arteries of diabetic versus non-diabetic patients (p=0.049) and in mononuclear cells of both type I and type II diabetes. In all study groups good glycemic control attenuated shortening of the telomeres. In arterial cells good glycemic control attenuated, but not abolished, the telomere shortening. In type II DM the mononuclear telomere attrition was completely prevented by adequate glycemic control. Telomere shortening in mononuclear cells of type I diabetic patients was attenuated but not prevented by good glycemic control. Results of this study suggest that diabetes is associated with premature cellular senescence which can be prevented by good glycemic control in type II DM and reduced in type I DM.  相似文献   

17.
Telomere length in human somatic cells gradually decreases with the number of cell divisions and is regarded as a marker of somatic cell turnover. Mucosal cells of the affected colon show rapid turnover in individuals with active ulcerative colitis (UC). Telomere length was determined by Southern blot analysis of terminal restriction fragments (TRFs) from the colonic mucosa of 17 patients with UC in remission, two of whom showed dysplasia, and 17 control subjects without colitis. For each individual, mean TRF length was compared between rectal mucosa and unaffected cecal mucosa. The mean TRF length of the rectal mucosa was significantly less than that of cecal mucosa in UC patients (7.87 ± 0.36 kb versus 8.77 ± 0.21 kb; P = 0.0015, Wilcoxon signed rank test), whereas no significant difference was detected in the control subjects. The extent of telomere shortening was 10.6 ± 3.35% in UC patients, compared with 0.8 ± 0.64% in noncolitis controls (P = 0.0024, Mann-Whitney U-test). Four UC patients, two of whom had dysplasia, showed telomere shortening of more than 20% in the rectal mucosa. These observations suggest that telomere shortening in the colonic mucosa of individuals with UC may represent the history of mucosal inflammation during disease of long duration, and that it may contribute to aneuploidy in UC. (Received May 6, 1997; accepted Sept. 26, 1997)  相似文献   

18.
Cawthon RM  Smith KR  O'Brien E  Sivatchenko A  Kerber RA 《Lancet》2003,361(9355):393-395
During normal ageing, the gradual loss of telomeric DNA in dividing somatic cells can contribute to replicative senescence, apoptosis, or neoplastic transformation. In the genetic disorder dyskeratosis congenita, telomere shortening is accelerated, and patients have premature onset of many age-related diseases and early death. We aimed to assess an association between telomere length and mortality in 143 normal unrelated individuals over the age of 60 years. Those with shorter telomeres in blood DNA had poorer survival, attributable in part to a 3.18-fold higher mortality rate from heart disease (95% CI 1(.)36-7.45, p=0.0079), and an 8.54-fold higher mortality rate from infectious disease (1.52-47.9, p=0.015). These results lend support to the hypothesis that telomere shortening in human beings contributes to mortality in many age-related diseases.  相似文献   

19.
Recent studies have demonstrated excessive telomeric shortening in peripheral blood leucocytes of bone marrow transplant (BMT) recipients. This finding has raised concerns about accelerated haemopoietic ageing that might predispose to clonal disorders and late graft failure. We studied the peripheral blood neutrophils and T cells of 14 fully engrafted long-term survivors of BMT.
We found that in both neutrophils and T cells there was significant telomere shortening in the recipient (0.6 and 0.5 kb, respectively; P  < 0.001 and < 0.04, respectively). We found no relationship between degree of shortening and the nucleated cell dose given at the time of transplant. We also demonstrated significantly longer telomeres in T cells than neutrophils from the same individual (mean 11.6 kb and 10.6 kb, respectively; P =0.0001).
We propose mechanisms to account for these observations. The replicative stress that causes this telomere shortening does not necessarily occur at the level of the most primitive haemopoietic stem cell.  相似文献   

20.
Systemic lupus erythematosus (SLE) patients suffer from excess cardiac deaths due to accelerated atherosclerosis. Endothelial dysfunction is a marker of early atherosclerosis. We tested the hypothesis that SLE patients have impaired endothelial function and assessed the relationship between endothelial function and clinical outcome over the subsequent five years. Thirty-six female SLE patients were compared with 22 healthy age and sex matched controls. Endothelial dependent vasodilatation (EDD) was assessed at the brachial artery in response to shear stress. Endothelium-independent dilatation induced by glyceryl trinitrate was also measured. Patients were followed for up to five years and the development of damage in the cardiovascular and other systems recorded. SLE patients showed significantly impaired endothelial function (median EDD 5.6%, IQR 3.1-7.2%) compared with healthy controls (median EDD 8.0%, IQR 6.3-9.3%; P = 0.001). Endothelium independent dilatation did not differ between the two groups. Endothelial function was significantly worse in postmenopausal compared with premenopausal women (median EDD 6.6%, IQR 3.9-7.8% versus 3.1%, IQR 2.6-5.1%; P = 0.016). Total cholesterol was inversely correlated with endothelial function in SLE patients (Spearman correlation r = -0.422, P = 0.025). There was no relationship between endothelial function and the development of damage in any organ system, including the cardiovascular system during patient follow-up. Patients with SLE have impaired endothelial Lupus (2007) 16, 84-88.  相似文献   

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