Serum sestrins: potential predictive molecule in human sarcopenia

Area of Science:

• Gerontology
• Muscle physiology
• Biochemistry

Background:

• Sarcopenia, a decline in skeletal muscle mass and function, is a key factor in aging, frailty, and disability.
• Autophagy, crucial for cellular health, appears impaired in aging skeletal muscle, contributing to sarcopenia.
• Sestrin (Sesn) proteins are vital for inducing autophagy under cellular stress.

Purpose of the Study:

• To identify sarcopenia in older adults using Asian Working Group guidelines (AWGS).
• To establish clinically relevant diagnostic cut-off levels for sarcopenia.
• To investigate the association between sarcopenia and serum levels of antioxidant proteins, Sestrins (Sesns).

Main Methods:

• Recruited 102 older adults from a Geriatric medicine outpatient department.
• Measured serum Sesn levels using Surface Plasmon Resonance (SPR) and validated with immunoblotting.
• Diagnosed 50 participants as sarcopenic based on AWGS criteria.

Main Results:

• Serum Sesn 1 and Sesn 2 levels were significantly lower in sarcopenic individuals compared to non-sarcopenic individuals.
• Receiver Operating Characteristic (ROC) analysis identified Sesn 2 at 10.104 ng/µL as a diagnostic cut-off with 92% sensitivity and 84% specificity.
• Reduced Sesn levels in sarcopenics remained statistically significant even after adjusting for confounding factors.

Conclusions:

• Serum Sesn 2 levels correlate positively with sarcopenia characteristics.
• This study is the first to report serum sestrin concentrations in older adults with sarcopenia.
• Serum sestrin levels may serve as a potential biomarker for early sarcopenia diagnosis.