A review of telomere length in sarcopenia and frailty

Abstract

Sarcopenia and frailty are associated with several important health-related adverse events, including disability, loss of independence, institutionalization and mortality. Sarcopenia can be considered a biological substrate of frailty, and the prevalence of both these conditions progressively increases with age. Telomeres are nucleoprotein structures located at the end of linear chromosomes and implicated in cellular ageing, shorten with age, and are associated with various age-related diseases. In addition, telomere length (TL) is widely considered a molecular/cellular hallmark of the ageing process. This narrative review summarizes the knowledge about telomeres and analyzes for the first time a possible association of TL with sarcopenia and frailty. The overview provided by the present review suggests that leukocyte TL as single measurement, calculated by quantitative real-time polymerase chain reaction (qRT-PCR), cannot be considered a meaningful biological marker for complex, multidimensional age-related conditions, such as sarcopenia and frailty. Panels of biomarkers, including TL, may provide more accurate assessment and prediction of outcomes in these geriatric syndromes in elderly people.

Telomere length and physical performance among older people—The Helsinki Birth Cohort Study

“…Thus, loss of muscle mass and muscle function due to telomere attrition could be a cause of poor physical performance (Zaslavsky et al, 2013). Another possible mechanism is oxidative stress and chronic inflammation, which has been shown to correlate with both telomere attrition (Lorenzi et al, 2018) and poor physical performance among older people (Cesari et al, 2004). This explanation is further supported by previous findings showing that senescent cells also secrete inflammatory mediators, such as interleukin-6 (Rodier et al, 2009).…”

“…Telomeres shorten at each cell division due to incomplete DNA replication at chromosome ends, however, the rate of telomere attrition is further induced by inflammation and oxidative stress as well as e.g. smoking and obesity (Lorenzi et al, 2018). Telomere length has been shown to correlate inversely with age and several age-related diseases including type 2 diabetes, cardiovascular disease, renal failure and Alzheimer's disease (Bernadotte et al, 2016).…”

Measuring biological aging in humans: A quest

“…Interestingly, significant amounts of telomere shortening were explained by decreased telomerase activity in the cells that express this enzyme, suggesting that measuring telomerase activity in human cells may be informative (Lin et al, ). Several reports indicate that short telomeres may be associated with central obesity (García‐Calzón et al, ; Mundstock et al, ), lifetime accumulation of stress (Epel et al, ; Osler, Bendix, Rask, & Rod, ; Puterman et al, ), increased risk of cardiovascular events (Baragetti et al, ; Hammadah et al, ), reduced immune response to influenza vaccination (Najarro et al, ), mortality (Batsis et al, ; Goglin et al, ; Heidinger et al, ), and several adverse health outcomes (Lin et al, ; Lorenzi et al, ; Lustig et al, ; Sanders & Newman, ). Genetic mutations associated with short telomeres have been shown to cause dyskeratosis congenita, pulmonary fibrosis, and several other severe medical conditions that are grouped under the definition of “telomere syndrome” (El‐Chemaly et al, ; Ungar et al, ).…”

Telomere length and aging‐related outcomes in humans: A Mendelian randomization study in 261,000 older participants

“…Telomere length is often approximated using leukocyte telomere length, which is easy to extract from blood and highly correlated with telomere length in other tissues (Daniali et al, ()). Measured telomere length has been associated with mortality and aging‐related outcomes in humans (Mather, Jorm, Parslow, & Christensen ; Sanders & Newman, ; Brown, Zhang, Mitchel, & Ailshire, ), including cancer (Zhang et al, ), cardiovascular disease (Haycock et al, ), cognitive function, physical performance such as grip strength, sarcopenia, and frailty (Lorenzi et al, ; Zhou et al, ), plus biomarkers of lung function, blood pressure, bone mineral density, cholesterol, interleukin 6, and C‐reactive protein. Observational associations cannot be consistently replicated likely due to study populations, measurement methods, and statistical modelling (Sanders & Newman, ).…”