The goal of this study is to establish a frail mouse model that can be utilized in future etiologic and intervention studies of the geriatric syndrome of frailty. The phenotypic characteristics sought in this model include age related declines in activity, muscle strength, and weight, and increased markers systemic inflammation as characterized by increased serum levels of the inflammatory cytokine IL-6. The IL-10tm/tm mouse has a decreased ability to counter NFkB related inflammatory activation, and our pilot data that shows that the IL-10tm/tm mouse develops age-related physical and physiological features that are consistent with frailty. We hypothesize that the IL-10tm/tm mouse will develop phenotypic alterations with increasing age consistent with human frailty as compared to age and gender matched C57Bl/6J control mice. We further hypothesize that these changes will result from the chronic activation of inflammatory pathways. In the first specific aim, we propose to longitudinally and cross-sectionally compare IL-10tm/tm mice with their age and gender matched C57Bl/6J control strain through assessments of muscle strength, balance, weight, and activity, complete blood counts, inflammatory marker profile, IGF-1 levels, skeletal muscle gene expression.
In specific aim 2, we propose to develop detailed studies of the causes of co-morbidities and mortality and compare them between IL-10tm/tm and control strain.
In specific aim three, we propose to extend our preliminary findings of altered mitochondrial related gene expression to explore mitochondrial function at different ages in skeletal muscle. The establishment of a frail mouse model caused by chronic activation of inflammatory pathways will greatly facilitate the ability of investigators to perform both etiologic and intervention studies of frailty, and enable a deeper biological understanding of incumbent co-morbidities and vulnerabilities of frail, older adults. The purpose of this project is to develop a frail mouse model that can be utilized to better understand the biological changes that develop with frailty. We will study the physical, physiological and molecular characteristics of the IL-10tm/tm mouse strain and compare it to a control mouse strain at several age points. We expect to find that the frail mouse has higher levels of inflammatory markers, muscle weakness, and altered gene expression as it gets older, similar to what is found in frail, older humans. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AG025143-01A2
Application #
7314547
Study Section
Aging Systems and Geriatrics Study Section (ASG)
Program Officer
Nayfield, Susan G
Project Start
2007-09-01
Project End
2009-05-31
Budget Start
2007-09-01
Budget End
2008-05-31
Support Year
1
Fiscal Year
2007
Total Cost
$201,720
Indirect Cost
Name
Johns Hopkins University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Chung, Tae; Tian, Yanli; Walston, Jeremy et al. (2018) Increased Single-Fiber Jitter Level Is Associated With Reduction in Motor Function With Aging. Am J Phys Med Rehabil 97:551-556
Chung, Tae; Park, Jae Sung; Kim, Sangri et al. (2017) Evidence for dying-back axonal degeneration in age-associated skeletal muscle decline. Muscle Nerve 55:894-901
Ko, Fred; Abadir, Peter; Marx, Ruth et al. (2016) Impaired mitochondrial degradation by autophagy in the skeletal muscle of the aged female interleukin 10 null mouse. Exp Gerontol 73:23-7
Ko, Fred; Yu, Qilu; Xue, Qian-Li et al. (2012) Inflammation and mortality in a frail mouse model. Age (Dordr) 34:705-15