Kumar R, Mohan N, Upadhyay AD, et al.
Aging Cell 2014;13:975-80
Publication date: December 1, 2014
Manifestations of frailty include sarcopenia (loss of skeletal muscle mass), cognitive decline, abnormal functioning of immune and neuroendocrine systems, and poor energy regulation. Diagnosis of frailty is often difficult because of subtle and subjective clinical features, especially in the early stage of the syndrome. Sirtuins belong to a family of nicotinamide adenine dinucleotide (NAD)-dependent protein deacetylases. Activation of sirtuins is one of the many mimics of calorie restriction which improves lifespan and health in experimental animals.
In this cross-sectional study, serum sirtuin concentration was assessed in frail and non-frail older subjects with the objective of examining it as a marker of frailty in old age. Two hundred patients 60 years of age or older attending Geriatric Medicine Outpatient Department for various indications were assessed for frailty status using Fried’s criteria; 59.5% were classified as non-frail and 40.5% as frail.
After adjustment for age, sex, diabetes mellitus, hypertension, cognitive status and number of comorbidities, serum SIRT1, SIRT2, and SIRT3 concentrations were found to be significantly lower in frail as compared to non-frail patients. Receiver operating characteristic (ROC) curves were generated for each protein. The calculated area for predicting non-frails was 0.9037 for SIRT1, 0.5756 for SIRT2, and 0.7988 for SIRT3, suggesting that both SIRT1 and SIRT3 can detect non-frail individuals.
This is the first study to report the clinically diagnostic relevance of SIRT1 and SIRT3 as serum protein marker for frailty.