Functional impact of diaphragm muscle sarcopenia in both male and female mice.
To perform a range of ventilatory and nonventilatory behaviors, the diaphragm muscle (DIAm) must be able to generate sufficient forces throughout the lifespan. We hypothesized that sarcopenia impacts DIAm force generation and thus limits performance of expulsive, higher force, nonventilatory behaviors. Male and female mice (n = 79) at 6 and 24 mo of age (100 vs. 70-75% survival, respectively) were used to examine transdiaphragmatic pressure (Pdi) generation across motor behaviors in vivo and in vitro DIAm specific force. We found a significant effect of age on maximum Pdi (20-41% decline during tracheal occlusion and bilateral phrenic nerve stimulation), maximum DIAm specific force (30% decline), and DIAm fatigue resistance (15% increase). There were no differences between sexes in these age effects on DIAm performance. These results support our hypothesis that sarcopenia primarily impacts higher force, nonventilatory motor behaviors of the DIAm. Such functional limitations may have negative implications in the ability of the DIAm to generate forces needed for airway clearance in old age and thereby contribute to age-related respiratory complications.
Department of Physiology and Biomedical Engineering, Mayo Clinic, College of Medicine, Rochester, Minnesota; and.
Sarah M
SM
Greising
Department of Physiology and Biomedical Engineering, Mayo Clinic, College of Medicine, Rochester, Minnesota; and Department of Anesthesiology, Mayo Clinic, College of Medicine, Rochester, Minnesota.
Carlos B
CB
Mantilla
Department of Physiology and Biomedical Engineering, Mayo Clinic, College of Medicine, Rochester, Minnesota; and.
Juan S
JS
Medina-Martínez
Department of Physiology and Biomedical Engineering, Mayo Clinic, College of Medicine, Rochester, Minnesota; and.
Jessica M
JM
Stowe
Department of Physiology and Biomedical Engineering, Mayo Clinic, College of Medicine, Rochester, Minnesota; and Department of Anesthesiology, Mayo Clinic, College of Medicine, Rochester, Minnesota sieck.gary@mayo.edu.
Gary C
GC
Sieck
D000375:Aging; D000818:Animals; D003964:Diaphragm / Q000502:physiology*; D005260:Female; D008171:Lung Diseases / Q000473:pathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018763:Muscle Fatigue / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D012119:Respiration; D055948:Sarcopenia / Q000503:physiopathology*; D012737:Sex Factors
aging; respiratory muscles; sex differences; transdiaphragmatic pressure