Novel Optical Sensors for Assessing the Effect of Aging on Muscle Health
Disciplines
Bioimaging and Biomedical Optics
Abstract (300 words maximum)
Sarcopenia is the age-related decline in muscle function and mass. This condition, exacerbated by chronic illnesses (e.g., kidney failure and heart disease), insulin resistance, prolonged immobility, and hormonal imbalances, significantly affects mobility, quality of life, and mortality in older adults. Since skeletal muscle energy production largely depends on mitochondrial capacity, understanding mitochondrial capacity is crucial for assessing skeletal muscle aging.
Traditional assessment methods, such as phosphorous nuclear magnetic resonance spectroscopy, are limited to specialized facilities and specific exercises due to their bulky and expensive nature. More recently, Continuous-Wave Near Infrared Spectroscopy (CW-NIRS) combined with arterial occlusion has been adopted, but the multiple occlusions required can be uncomfortable and unsuitable for older adults. To address this limitation, we propose utilizing Diffuse Correlation Spectroscopy (DCS) to measure oxygen delivery (i.e., muscle blood flow) alongside NIRS.
In this pilot study, we evaluated a new method for assessing mitochondrial capacity using DCS and NIRS simultaneously. The MetaOx (ISS Inc., DCS + NIRS) sensor was placed on the flexor digitorum profundus of four participants. Muscle oxygenation and blood flow data were continuously acquired while participants performed dynamic exercise using a hand-grip dynamometer (two minutes of rest, three minutes of exercise, two minutes of recovery). We calculated muscle oxygen consumption from oxygenation and blood flow measurements and determined the rate of decay (i.e., mitochondrial capacity) in oxygen consumption after the exercise period. The mitochondrial capacity values (time constant = 4.30 min⁻¹ ± 0.64, average ± std. dev.) from our four subjects were consistent with those reported in the literature using NIRS + arterial occlusion.
Our pilot results demonstrate that this new method is a feasible, non-invasive approach to assess mitochondrial capacity without requiring arterial occlusion. Because of its non-occlusive and portable nature, this technique has the potential for wide application in home-based monitoring of older adults.
Academic department under which the project should be listed
SPCEET - Electrical and Computer Engineering
Primary Investigator (PI) Name
Dr. Paul Lee
Additional Faculty
Garrett Hester, Department of Exercise Science and Sport Management, ghester4@kennesaw.edu
Novel Optical Sensors for Assessing the Effect of Aging on Muscle Health
Sarcopenia is the age-related decline in muscle function and mass. This condition, exacerbated by chronic illnesses (e.g., kidney failure and heart disease), insulin resistance, prolonged immobility, and hormonal imbalances, significantly affects mobility, quality of life, and mortality in older adults. Since skeletal muscle energy production largely depends on mitochondrial capacity, understanding mitochondrial capacity is crucial for assessing skeletal muscle aging.
Traditional assessment methods, such as phosphorous nuclear magnetic resonance spectroscopy, are limited to specialized facilities and specific exercises due to their bulky and expensive nature. More recently, Continuous-Wave Near Infrared Spectroscopy (CW-NIRS) combined with arterial occlusion has been adopted, but the multiple occlusions required can be uncomfortable and unsuitable for older adults. To address this limitation, we propose utilizing Diffuse Correlation Spectroscopy (DCS) to measure oxygen delivery (i.e., muscle blood flow) alongside NIRS.
In this pilot study, we evaluated a new method for assessing mitochondrial capacity using DCS and NIRS simultaneously. The MetaOx (ISS Inc., DCS + NIRS) sensor was placed on the flexor digitorum profundus of four participants. Muscle oxygenation and blood flow data were continuously acquired while participants performed dynamic exercise using a hand-grip dynamometer (two minutes of rest, three minutes of exercise, two minutes of recovery). We calculated muscle oxygen consumption from oxygenation and blood flow measurements and determined the rate of decay (i.e., mitochondrial capacity) in oxygen consumption after the exercise period. The mitochondrial capacity values (time constant = 4.30 min⁻¹ ± 0.64, average ± std. dev.) from our four subjects were consistent with those reported in the literature using NIRS + arterial occlusion.
Our pilot results demonstrate that this new method is a feasible, non-invasive approach to assess mitochondrial capacity without requiring arterial occlusion. Because of its non-occlusive and portable nature, this technique has the potential for wide application in home-based monitoring of older adults.