Rate Of Telomere Shortening Research Articles

Structural chromosome abnormalities, increased DNA strand breaks and DNA strand break repair deficiency in dermal fibroblasts from old female human donors

Dermal fibroblasts provide a paradigmatic model of cellular adaptation to long-term exogenous stress and ageing processes driven thereby. Here we addressed whether fibroblast ageing analysedex vivo entails genome instability. Dermal fibroblasts from human female donors aged 20-67 years were studied in primary culture at low population doubling. Under these conditions, the incidence of replicative senescence and rates of age-correlated telomere shortening were insignificant. Genome-wide gene expression analysis revealed age-related impairment of mitosis, telomere and chromosome maintenance and induction of genes associated with DNA repair and non-homologous end-joining, most notably XRCC4 and ligase 4. We observed an age-correlated drop in proliferative capacity and age-correlated increases in heterochromatin marks, structural chromosome abnormalities (deletions, translocations and chromatid breaks), DNA strand breaks and histone H2AX-phosphorylation. In a third of the cells from old and middle-aged donors repair of X-ray induced DNA strand breaks was impaired despite up-regulation of DNA repair genes. The distinct phenotype of genome instability, increased heterochromatinisation and (in 30% of the cases futile) up-regulation of DNA repair genes was stably maintained over several cell passages indicating that it represents a feature of geroconversion that is distinct from cellular senescence, as it does not encompass a block of proliferation.

Physical Activity May Improve Aging Through Impacts on Telomere Biology

Physical activity has long been touted as a means of reducing susceptibility to age-related disease and multiple studies have shown reduced mortality rates in individuals with a lifestyle including regular exercise. A variety of mechanisms for how physical activity reduces age-related diseases have been explored and multiple, redundant explanatory mechanisms are likely to emerge. Evidence has emerged that physical activity may impact directly on telomere biology, one of the primary theories of cellular aging. Telomeres are located at the ends of chromosomes and as cells divide, incomplete DNA replication results in telomere shortening; once shortening reaches a critical threshold, cell senescence results. Investigators hypothesize that part of the favorable influence of physical activity on mortality rates and age-related disease occurs through a direct impact on telomere biology, including delaying rates of telomere shortening. The present review examines key recent findings in this area and explores some of the unanswered questions and future directions for the field.

Accelerated telomere shortening in β-thalassemia/HbE patients.

β-Thalassemia/HbE disease is caused by a defective β-globin synthesis that leads to accumulation of excess unbound α-globins, and consequently oxidative stress, ineffective erythropoiesis and chronic anemia. Cell replication and oxidative stress are factors contributing to erosion of telomeres responsible for maintaining genomic stability and cell replication capability. In this study, the rate of telomere shortening in β-thalassemia/HbE patients was compared to the rate of telomere shortening in normal individuals. Telomere length was determined from peripheral blood mononuclear cells of 43 β-thalassemia/HbE patients and 22 normal controls using Flow-FISH analysis. The telomere length was shown to be age-dependent in normal group (rs = 0.715, P = 0.002), whereas severity-dependent telomere shortening was observed in the patients. The telomere length of patients who had severe clinical symptoms (10.07 ± 2.15%) was shorter than that of patients who showed mild symptoms (15.59 ± 2.27%), moderate symptoms (14.50 ± 1.41%) and those in the normal group (14.75 ± 3.11%, P < 0.05). Additionally, reticulocyte count and oxidative stress were correlated with telomere length. This indicates that increased oxidative stress and markedly enhanced erythropoiesis in β-thalassemia/HbE patients leads to accelerated telomere erosion in clinically severe patients.

SLEEP DURATION: MODERN VIEW OF THE PROBLEM FROM THE STANDPOINT OF A CARDIOLOGIST

Today the role of disturbances in sleep duration in the development of various chronic diseases, including cardiovascular diseases is known and proven. In addition, the results of many clinical studies demonstrate the relationship between impaired sleep duration and the rate of telomere shortening. In turn, short telomeres are associated with the development of arterial hypertension, chronic heart failure, atherosclerosis and other diseases with high mortality both in Russia and worldwide. This article presents an overview of the clinical studies demonstrating the negative effect of sleep duration disturbances on total and cardiovascular mortality, as well as works that specify in detail the relation between sleep duration and telomere length.

LOW SODIUM DIET: PROS AND CONS

Currently, there is rather contradictory evidence on the effectiveness of a low sodium diet for the prevention of various diseases. At that, it is a generally accepted fact, that it is necessary to reduce salt intake in order to reduce high blood pressure. An internist should remember that the degree of blood pressure reduction is individual and not always depends on the level of salt intake. Moreover, the low-sodium diet helps to reduce the rate of telomere shortening, thereby slowing down the aging process.

OMEGA-3 FATTY ACIDS AND AGE-RELATED DISEASES: REALITIES AND PROSPECTS

Efficacy of omega-3 fatty acids in cardiology is so high that in many countries omega-3 fatty acids are included into the treatment protocols for patients with cardiovascular diseases. This therapeutic class slows down oxidative stress and chronic inflammation processes, thereby providing a significant contribution to the complex treatment of hypertension. Besides, omega-3 fatty acids slow down the aging process and prevent the development of age-related diseases affecting the rate of telomere shortening.

Novel neuroendocrine and metabolic mechanism provides the patented platform for important rejuvenation therapies: targeted therapy of telomere attrition and lifestyle changes of telomerase activity with the timing of neuron-specific imidazole-containing dipeptide-dominant pharmaconutrition provision.

Telomere length is emerging as a biomarker for aging and survival is paternally inherited and associated with parental lifespan. Telomere-associated cellular senescence may contribute to certain age-related disorders, including an increase in cancer incidence, wrinkling and diminished skin elasticity, atherosclerosis, osteoporosis, weight loss, age-related cataract, glaucoma and others. Shorter telomere length in leukocytes was associated cross-sectionally with cardiovascular disorders and its risk factors, including pulse pressure and vascular aging, obesity, vascular dementia, diabetes, coronary artery disease, myocardial infarction (although not in all studies), cellular turnover and exposure to oxidative and inflammatory damage in chronic obstructive pulmonary disease. Effective regulation of abnormal therapeutic targets of an age-related disease requires the alteration of either the topological structure or dynamic characteristics of telomeres which are DNA-protein structures at the ends of eukaryotic chromosomes, the DNA of which comprise noncoding repeats of guanine-rich sequences. Telomeric DNA plays a fundamental role in protecting the cell from recombination and degradation, including those as the metabolic super-achievers in the body, organ systems in a given target network of a disease and aging. In order to manage and control the complex direct and indirect target hubs, in this paper, a review of the recent patents is made analyzing techniques, new approaches developed during the last years in adaptive pharmacology directed at slowing and preventing the loss of telomere length that may slow aging using pharmaceutical and nutritional module-based designs, such as with regard to the timing of administration of imidazole-containing dipeptides. We discuss our recent identification of the role of neuron-specific imidazole- containing dipeptide based compounds (L-carnosine, N-acetylcarnosine, carcinine) that regulate and therapeutically control telomere shortening, telomerase activity and cellular senescence. We support a therapeutic concept of using nonhydrolyzed forms of naturally occurring imidazole-dipeptide based compounds carnosine and carcinine, making it clinically possible that slowing down the rate of telomere shortening could slow down the human aging process in specific tissues where proliferative senescence is known to occur with the demonstrated evidence of telomere shortening appeared to be a hallmark of oxidative stress and disease. The preliminary longitudinal studies of elderly individuals suggest that longer telomeres are associated with better survival and an advanced oral pharmaconutrition provision with non-hydrolyzed carnosine (or carcinine and patented compositions thereof) is a useful therapeutic tool of a critical telomere length maintenance (allowing indirectly to manipulate with telomerase activity) that may fundamentally be applied in the therapeutic treatment of agerelated sight-threatening eye disorders, Diabetes mellitus, sarcopenia (that is the gradual loss of muscle mass) that can affect elderly people and subjects under the effect of exhausting exercises and physical load, prolong life expectancy, increase survival and chronological age of an organism in health control, smoking behavior, metabolic syndrome increasing the risk of developing cardio-vascular diseases, age-related neurodegenerative diseases, including Alzheimer's disease and cognitive impairment.

Oxidative stress induces persistent telomeric DNA damage responsible for nuclear morphology change in mammalian cells.

One main function of telomeres is to maintain chromosome and genome stability. The rate of telomere shortening can be accelerated significantly by chemical and physical environmental agents. Reactive oxygen species are a source of oxidative stress and can produce modified bases (mainly 8-oxoG) and single strand breaks anywhere in the genome. The high incidence of guanine residues in telomeric DNA sequences makes the telomere a preferred target for oxidative damage. Our aim in this work is to evaluate whether chromosome instability induced by oxidative stress is related specifically to telomeric damage. We treated human primary fibroblasts (MRC-5) in vitro with hydrogen peroxide (100 and 200 µM) for 1 hr and collected data at several time points. To evaluate the persistence of oxidative stress-induced DNA damage up to 24 hrs after treatment, we analysed telomeric and genomic oxidative damage by qPCR and a modified comet assay, respectively. The results demonstrate that the genomic damage is completely repaired, while the telomeric oxidative damage persists. The analysis of telomere length reveals a significant telomere shortening 48 hrs after treatment, leading us to hypothesise that residual telomere damage could be responsible for the telomere shortening observed. Considering the influence of telomere length modulation on genomic stability, we quantified abnormal nuclear morphologies (Nucleoplasmic Bridges, Nuclear Buds and Micronuclei) and observed an increase of chromosome instability in the same time frame as telomere shortening. At subsequent times (72 and 96 hrs), we observed a restoration of telomere length and a reduction of chromosome instability, leaving us to conjecture a correlation between telomere shortening/dysfunction and chromosome instability. We can conclude that oxidative base damage leads to abnormal nuclear morphologies and that telomere dysfunction is an important contributor to this effect.

Oxidative damage impact on aging and age-related diseases: drug targeting of telomere attrition and dynamic telomerase activity flirting with imidazole-containing dipeptides.

It has been documented that telomere-associated cellular senescence may contribute to certain age-related disorders, including an increase in cancer incidence, wrinkling and diminished skin elasticity, atherosclerosis, osteoporosis, weight loss, age-related cataract, glaucoma and others. Shorter telomere length in leukocytes was associated crosssectionally with cardiovascular disorders and their risk factors, including pulse pressure and vascular aging, obesity, vascular dementia, diabetes, coronary artery disease, myocardial infarction (although not in all studies), cellular turnover and exposure to oxidative and inflammatory damage in chronic obstructive pulmonary disease. It has been proposed that telomere length may not be a strong biomarker of survival in older individuals, but it may be an informative biomarker of healthy aging. The data reveal that telomere dynamics and changes in telomerase activity are consistent elements of cellular alterations associated with changes in proliferative state and in this article these processes are consequently considered as the new therapeutic drug targets for physiological control with advanced drug delivery and nutritional formulations. In particular, the presence of highly specific correlations and early causal relationships between telomere loss in the absence of telomerase activity and replicative senescence or crisis, and from the other side, telomerase reactivation and cell immortality, point to new and important treatment strategies or the therapeutic manipulation during treatment of age related disorders and cancer. Once better controls and therapeutic treatments for aging and age-related disorders are achieved, cellular rejuvenation by manipulating telomeres and enzyme telomerase activity may reduce some of the physiological declines that accompany aging. In this work, we raise and support a therapeutic concept of using non-hydrolyzed forms of naturally occurring imidazoledipeptide based compounds carnosine and carcinine, making it clinically possible that slowing down the rate of telomere shortening could slow down the human aging process in specific tissues where proliferative senescence is known to occur with the demonstrated evidence of telomere shortening appeared to be a hallmark of oxidative stress and disease. The preliminary longitudinal studies of elderly individuals suggest that longer telomeres are associated with better survival and an advanced oral nutritional support with non-hydrolyzed carnosine (or carcinine and patented compositions thereof) and patented N-acetylcarnosine lubricant eye drops are useful therapeutic tools of a critical telomere length maintenance that may fundamentally be applied in the treatment of age-related sight-threatening eye disorders, prolong life expectancy, increase survival and chronological age of an organism in health control, smoking behavior and disease.

Hormone-brain-aging relationships, broadly reactive with imidazole-containing dipeptides: targeting of telomere attrition as an aging biomarker and dynamic telomerase activity flirting.

It has been documented that telomere-associated cellular senescence may contribute to certain age-related disorders, and telomere length (TL) may be an informative biomarker of healthy aging. Hormone-brain-aging behavior-modulated telomere dynamics and changes in telomerase activity are consistent elements of cellular alterations associated with changes in proliferative state, and these processes are consequently considered as the new therapeutic drug targets for physiological control with advanced drug delivery and nutritional formulations. We raise and support a therapeutic concept of using nonhydrolyzed forms of naturally occurring neuron-specific imidazole dipeptide-based compounds carnosine and carcinine, making it clinically possible that slowing down the rate of telomere shortening could slow down the human aging process in specific tissues where proliferative senescence is known to occur, with the demonstrated evidence of telomere shortening that appeared to be a hallmark of oxidative stress and disease. Carnosine released from skeletal muscle during exercise may be transported into the hypothalamic tuberomammillary nucleus (TMN) histamine neurons and hydrolyzed. The resulting L-histidine may subsequently be converted into histamine, which could be responsible for the effects of carnosine on neurotransmission and hormone-like antiaging physiological function. The preliminary longitudinal studies of elderly individuals suggest that longer telomeres are associated with better survival, and an advanced oral nutritional support with nonhydrolyzed carnosine (or carcinine and patented compositions thereof) is a useful therapeutic tool for a critical TL maintenance that may fundamentally be applied in the treatment of age-related sight-threatening eye disorders, prolonged life expectancy, increased survival and chronological age of an organism in health control, smoking behavior, and disease. "Our pleasures were simple-they included survival." -Dwight D. Eisenhower, 34th President of the United States, 1953-1961.

닭의 품종 간 스트레스 반응 정도 비교 분석

본 연구에서는 닭의 품종에 따른 개체의 스트레스 반응정도를 알아보고자 한국 재래닭과 단관 백색 레그혼종을 공시하고, 고밀도 사육에 따른 생리적 스트레스 표지 값을 비교 분석하였다. 스트레스 반응 정도는 혈액과 각 조직별 세포들에 대한 텔로미어 함량, DNA 손상율 및 열 스트레스 단백질(HSPs) 유전자의 발현율을 분석하고 비교하였다. 텔로미어 함량 및 감축율은 양적 형광 접합 보인법으로 분석하였고, DNA 손상율은 Comet assay로 분석하였다. 열 스트레스 단백질 유전자 발현율은 HSP70, HSP90-<TEX>${\alpha}$</TEX>, HSP90-<TEX>${\beta}$</TEX> 및 HMGCR을 표적으로 하여 real-time PCR로 분석하였다. 분석 결과, 한국 재래닭과 단관 백색 레그혼 간 품종에 따른 체중, 증체량, 텔로미어 감축율 및 DNA 손상율의 차이는 없는 것으로 나타났다. 그러나 고밀도 사육과 같은 스트레스 사양 관리는 품종에 상관없이 닭의 성장을 저해하고, 텔로미어 감축 및 DNA 손상을 촉진시키는 것으로 나타났다. 한편, HMGCR을 제외한 HSPs 유전자 발현율의 경우, 밀사 사육에 따른 요인뿐만 아니라, 품종 간에도 유의적 차이를 보였다. HSPs의 분석에 따른 스트레스 정도는 단관 백색 레그혼종이 한국 재래닭에 비해 보다 민감하게 반응하는 것으로 나타났다. 따라서 품종과 관계없이 닭에 있어 고밀도 사육이 강한 환경적 스트레스 요인임을 시사하고, 품종 간 스트레스의 반응 정도는 레그혼종이 한국 재래닭에 비해 다소 높은 것으로 사료된다. With Single Comb White Leghorn (WL) and Korean Native Chicken (KNC) breeds, we compared the stress response with chicken breeds that were subjected to a high stocking density. Stress response was analyzed by the quantity of telomeric DNA, the rate of DNA damage and the expression levels of heat shock proteins (HSPs) and hydroxyl-3-methyl-glutaryl coenzyme A reductase (HMGCR) genes on tissues and blood. The telomere length and telomere shortening rates were analyzed by quantitative fluorescence in situ hybridization on the nuclei of lymphocytes and tissues. The DNA damage rate of lymphocytes was quantified by the comet assay. The expression levels of HSP70, HSP90-<TEX>${\alpha}$</TEX>, HSP90-<TEX>${\beta}$</TEX> and HMGCR genes were measured by quantitative real-time polymerase chain reaction in lymphocytes. There was no significant difference between KNC and WL in body weight, weight gain, telomere shortening rate and DNA damage rate. However, the growth rate significantly decreased in chickens raised under high stocking density conditions, as compared to the control group. The telomere-shortening rate, DNA damage and HSPs expression of the lymphocytes were significantly higher in the high stocking density group than the control. The stress condition and breeds had a significant effect on the expressions of HSP70, HSP90-<TEX>${\alpha}$</TEX> and HSP90-<TEX>${\beta}$</TEX> in lymphocytes, except HMGCR. The stress response of WL was higher than that of KNC, as analyzed to the expression of HSP70 and HSP90-<TEX>${\alpha}$</TEX>. Therefore, we concluded that the chickens which were exposed to a high stocking density had increased the individual physiological stress response regardless of breeds, and White Leghorns are more susceptible to stress condition than Korean Native Chickens.

Rate of telomere shortening and cardiovascular damage: a longitudinal study in the 1946 British Birth Cohort.

AimCross-sectional studies reported associations between short leucocyte telomere length (LTL) and measures of vascular and cardiac damage. However, the contribution of LTL dynamics to the age-related process of cardiovascular (CV) remodelling remains unknown. In this study, we explored whether the rate of LTL shortening can predict CV phenotypes over 10-year follow-up and the influence of established CV risk factors on this relationship.Methods and resultsAll the participants from the MRC National Survey of Health and Development (NSHD) with measures of LTL and traditional CV risk factors at 53 and 60–64 years and common carotid intima-media thickness (cIMT), cardiac mass and left ventricular function at 60–64 years were included. LTL was measured by real-time polymerase chain reaction and available at both time points in 1033 individuals. While LTL at 53 years was not linked with any CV phenotype at 60–64 years, a negative association was found between LTL and cIMT at 60–64 years (β = −0.017, P = 0.015). However, the strongest association was found between rate of telomere shortening between 53 and 60–64 years and values of cIMT at 60–64 years (β = −0.020, P = 0.006). This association was not affected by adjustment for traditional CV risk factors. Cardiac measurements were not associated with cross-sectional or longitudinal measures of LTL.ConclusionThese findings suggest that the rate of progression of cellular ageing in late midlife (reflected by the rate of LTL attrition) relates to vascular damage, independently from contribution of CV risk factor exposure.

No association between mean telomere length and life stress observed in a 30 year birth cohort.

Telomeres are specialised structures that cap the ends of chromosomes. They shorten with each cell division and have been proposed as a marker of cellular aging. Previous studies suggest that early life stressors increase the rate of telomere shortening with potential impact on disease states and mortality later in life. This study examined the associations between telomere length and exposure to a number of stressors that arise during development from the antenatal/perinatal period through to young adulthood. Participants were from the Christchurch Health and Development Study (CHDS), a New Zealand longitudinal birth cohort which has followed participants from birth until age 30. Telomere length was obtained on DNA from peripheral blood samples collected from consenting participants (n = 677) at age 28–30, using a quantitative PCR assay. These data were assessed for associations with 26 measures of life course adversity or stress which occurred prior to 25 years of age. No associations were found between telomere length measured at age 28–30 years and life course adversity or stress for specific measures and for the summary risk scores for each developmental domain. The correlations were very small ranging from −0.06 to 0.06 with a median of 0.01, and none were statistically significant. Our results in this well-studied birth cohort do not support prior reports of such associations, and underscore the need for more extensive replication of proposed links between stress and telomere biology in larger cohorts with appropriate phenotypic data.

Race-related health disparities and biological aging: Does rate of telomere shortening differ across blacks and whites?

Recent work suggests that leukocyte telomere length (LTL), a marker of cellular aging, is sensitive to effects of social stress and may also provide early indication of premature aging. Using data from a birth cohort with LTL information at birth and in middle adulthood we examined a potential source of race-based health disparity by testing the hypothesis that Blacks would demonstrate a faster rate of telomere shortening than Whites. Linear regression analyses were conducted and adjusted for pack years, BMI, education and social factors, diet, exercise, marital status, and age. At birth black individuals had LTLs that were longer, on average, than their White counterparts (b=3.85, p<0.01). However, rate of shortening was greater for Blacks, who showed a larger difference in length between birth and adulthood (b=5.10, p=0.01) as compared with Whites, resulting in smaller racial differences in absolute adult LTL.

Blood cell telomere lengths and shortening rates of chimpanzee and human females

Slower rates of aging distinguish humans from our nearest living cousins. Chimpanzees rarely survive their forties while large fractions of women are postmenopausal even in high-mortality hunter-gatherer populations. Cellular and molecular mechanisms for these somatic aging differences remain to be identified, though telomeres might play a role. To find out, we compared telomere lengths across age-matched samples of female chimpanzees and women. We used a monochrome multiplex quantitative polymerase chain reaction to assay canonical telomere repeats in blood cells from captive female chimpanzees (65 individuals; age: 6.2-56.7 years) and compared them to the same measure in human females (43 individuals; age: 7.4-57.3 years). Our samples showed little difference in attrition rates between the species (~0.022 T/S per year for chimpanzees and ~0.012 T/S per year for humans with overlapping 95% confidence intervals), but telomeres were twice as long in chimpanzees as in humans (T/S ratios = 2.70 and 1.26, respectively). Based on the longevity differences, we initially hypothesized that telomere shortening rates would be faster in chimpanzees than in humans. Instead, it is shorter telomere length that appears to be the derived state in humans. This comparison indicates that better characterization of physiological aging in our closest living relatives will be indispensable for understanding the evolution of distinctive human longevity.

Stress induced telomere shortening: longer life with less mutations?

BackgroundMutations accumulate as a result of DNA damage and imperfect DNA repair machinery. In higher eukaryotes the accumulation and spread of mutations is limited in two primary ways: through p53-mediated programmed cell death and cellular senescence mediated by telomeres. Telomeres shorten at every cell division and cell stops dividing once the shortest telomere reaches a critical length. It has been shown that the rate of telomere attrition is accelerated when cells are exposed to DNA damaging agents. However the implications of this mechanism are not fully understood.ResultsWith the help of in silico model we investigate the effect of genotoxic stress on telomere attrition and apoptosis in a population of non-identical replicating cells. When comparing the populations of cells with constant vs. stress-induced rate of telomere shortening we find that stress induced telomere shortening (SITS) increases longevity while reducing mutation rate. Interestingly, however, the effect takes place only when genotoxic stresses (e.g. reactive oxygen species due to metabolic activity) are distributed non-equally among cells.ConclusionsOur results for the first time show how non-equal distribution of metabolic load (and associated genotoxic stresses) combined with stress induced telomere shortening can delay aging and minimize mutations.

The Long and Short of Telomere Length and Diabetes

Aging is a major risk factor for a number of complex diseases including cancers, cardiovascular disease, and type 2 diabetes, yet the biological processes linking aging and disease risk are poorly understood. A potential mediator of age-related increases in disease risk may lie in repetitive sequences of DNA known as telomeres. Telomeres represent the genome’s defense mechanism against the biological conundrum that the tail ends of chromosomes cannot be replicated when cells divide (1). During mitosis, telomeric DNA is sacrificed in return for protecting the protein coding and regulatory elements of the genome, and as a result they become shorter with cellular aging (2). The enzyme telomerase helps to guard against this telomere loss by making additional copies of the hexanucleotide repeats that make up these protective chromosomal caps (3). However, when a critical threshold of shortening is reached (the “Hayflick limit”), cell senescence follows (4). While telomeres are shorter in older age (5), the rate of telomere shortening varies among individuals (6). The association of shorter telomeres with disease and mortality (7) implicates telomeres as a biomarker of biological aging (8). Telomere shortening is influenced by a range of cellular stressors (9) such that telomere length may lie on the causal pathway between lifestyle exposures and risk of disease. Previous studies have highlighted the role of health behaviors in …

Nestling telomere length does not predict longevity, but covaries with adult body size in wild barn swallows

Telomere length and dynamics are increasingly scrutinized as ultimate determinants of performance, including age-dependent mortality and fecundity. Few studies have investigated longevity in relation to telomere length (TL) in the wild and none has analysed longevity in relation to TL soon after hatching, despite the fact that telomere shortening may mostly occur early in life. We show that TL in nestling barn swallows (Hirundo rustica) in the wild does not predict longevity. However, TL positively covaries with body size, suggesting that individuals with large TL can afford to grow larger without paying the cost of reduced TL, and/or that benign rearing conditions ensure both large body size and low rates of telomere shortening. Overall, our study hints at a role of TL in developmental processes, but also indicates a need for further analyses to assess the expectation that TL in young individuals predicts longevity in the wild.

The Effect of Pro-Inflammatory Conditioning and/or High Glucose on Telomere Shortening of Aging Fibroblasts

Cardiovascular disease and diabetes have been linked to shorter telomeres, but it is not yet clear which risk factors contribute to shorter telomeres in patients. Our aim was to examine whether pro-inflammatory conditioning, in combination or not with high glucose, result in a higher rate of telomere shortening during in vitro cellular ageing. Human fibroblasts from four donors were cultured for 90 days in: 1) medium lacking ascorbic acid only, 2) 10 mM buthionine sulphoximine (BSO) (pro-oxidant), 3) 25 mM D-glucose, 4) 1 ng/ml IL1B and 5) 25 mM D-glucose+1 ng/ml IL1B. Telomere length was measured with qPCR and intracellular reactive oxygen species (ROS) content and cell death with flow cytometry. Cultures treated with high glucose and BSO displayed a significantly lower growth rate, and cultures treated with IL1B showed a trend towards a higher growth rate, compared to the control [Glucose:0.14 PD/day, p<0.001, BSO: 0.11 PD/day, p = 0.006 and IL1B: 0.19 PD/day, p = 0.093 vs. Control:0.16 PD/day]. Telomere shortening with time was significantly accelerated in cultures treated with IL1B compared to the control [IL1B:−0.8%/day (95%CI:−1.1, −0.5) vs. Control:−0.6%/day (95%CI:−0.8, −0.3), p = 0.012]. The hastening of telomere shortening by IL1B was only in part attenuated after adjustment for the number of cell divisions [IL1B:−4.1%/PD (95%CI:−5.7, −2.4) vs. Control:−2.5%/PD (95%CI:−4.4, −0.7), p = 0.067]. The intracellular ROS content displayed 69% increase (p = 0.033) in BSO compared to the control. In aging fibroblasts, pro-inflammatory conditioning aggravates the shortening of telomeres, an effect which was only in part driven by increased cell turnover. High glucose alone did not result in greater production of ROS or telomere shortening.

Leukocyte telomere length in mastocytosis: Correlations with depression and perceived stress

Mastocytosisis a rare disease associated with chronic symptoms related to mast cell mediator release. Patients with mastocytosis display high level of negative emotionality such as depression and stress sensibility. Brain mast cells are mainly localized in the diencephalon, which is linked to emotion regulatory systems. Negative emotionality has been shown to be associated with telomere shortening. Taken together these observations led us to hypothesize that mast cells activity could be involved in both negative emotionality and telomere shortening in mastocytosis. To demonstrate a possible relationship between negative emotionality in mastocytosis and leukocytes telomere length. Leukocyte telomere length and telomerase activity were measured among mastocytosis patients and were correlated with perceived stress and depression assessed by the Beck Depression Inventory revised and the Perceived Stress Scale. Mild-severe depression scores were frequent (78.9%) as well as high perceived stress (42.11%). Telomere length was correlated to perceived stress (r=0.77; p=0.0001) but not to depression in our population. Patients displaying Wild-type KIT significantly presented higher perceived stress levels. Patients with the D816VC KIT mutation who had high perceived stress scores displayed significantly shorter telomere but not if they had high depression scores. These findings suggest that high perceived stress in mastocytosis could accelerate the rate of leukocytes telomere shortening. Since mastocytosis is, by definition, a mast cell mediated disease; these cells could be involved in this phenomenon. Mechanistic causal relationships between these parameters need to be investigated.