Medicine and Health Sciences Commons^™

Deletion Of Sa Β-Gal+ Cells Using Senolytics Improves Muscle Regeneration In Old Mice, Cory M. Dungan, Kevin A. Murach, Christopher J. Zdunek, Zuo Jian Tang, Georgia L. Vonlehmden, Camille R. Brightwell, Zachary Hettinger, Davis A. Englund, Zheng Liu, Christopher S. Fry, Antonio Filareto, Michael Franti, Charlotte A. Peterson

Physical Therapy Faculty Publications

Systemic deletion of senescent cells leads to robust improvements in cognitive, cardiovascular, and whole-body metabolism, but their role in tissue reparative processes is incompletely understood. We hypothesized that senolytic drugs would enhance regeneration in aged skeletal muscle. Young (3 months) and old (20 months) male C57Bl/6J mice were administered the senolytics dasatinib (5 mg/kg) and quercetin (50 mg/kg) or vehicle bi-weekly for 4 months. Tibialis anterior (TA) was then injected with 1.2% BaCl₂ or PBS 7- or 28 days prior to euthanization. Senescence-associated β-Galactosidase positive (SA β-Gal+) cell abundance was low in muscle from both young and old mice …

Lat1 Protein Content Increases Following 12 Weeks Of Resistance Exercise Training In Human Skeletal Muscle, Paul A. Roberson, Christopher Brooks Mobley, Matthew A. Romero, Cody T. Haun, Shelby C. Osburn, Petey W. Mumford, Christopher G. Vann, Rory A. Greer, Arny A. Ferrando, Michael D. Roberts

Physiology Faculty Publications

Introduction: Amino acid transporters are essential for cellular amino acid transport and promoting protein synthesis. While previous literature has demonstrated the association of amino acid transporters and protein synthesis following acute resistance exercise and amino acid supplementation, the chronic effect of resistance exercise and supplementation on amino acid transporters is unknown. The purpose herein was to determine if amino acid transporters and amino acid metabolic enzymes were related to skeletal muscle hypertrophy following resistance exercise training with different nutritional supplementation strategies.

Methods: 43 college-aged males were separated into a maltodextrin placebo (PLA, n = 12), leucine (LEU, n = 14), …

Correlations Of Calf Muscle Macrophage Content With Muscle Properties And Walking Performance In Peripheral Artery Disease, Kate Kosmac, Marta Gonzalez-Freire, Mary M. Mcdermott, Sarah H. White, R. Grace Walton, Robert L. Sufit, Lu Tian, Lingyu Li, Melina R. Kibbe, Michael H Criqui, Jack M. Guralnik, Tamar S. Polonsky, Christiaan Leeuwenburgh, Luigi Ferrucci, Charlotte A. Peterson

Physical Therapy Faculty Publications

Background

Peripheral artery disease (PAD) is a manifestation of atherosclerosis characterized by reduced blood flow to the lower extremities and mobility loss. Preliminary evidence suggests PAD damages skeletal muscle, resulting in muscle impairments that contribute to functional decline. We sought to determine whether PAD is associated with an altered macrophage profile in gastrocnemius muscles and whether muscle macrophage populations are associated with impaired muscle phenotype and walking performance in patients with PAD.

Methods and Results

Macrophages, satellite cells, and extracellular matrix in gastrocnemius muscles from 25 patients with PAD and 7 patients without PAD were quantified using immunohistochemistry. Among patients …

Association Of Skeletal Muscle And Psychological Responses To Immobility After Major Injury, Jacob T. Higgins

Theses and Dissertations--Nursing

The purpose of this dissertation was to explore the physical and psychological responses to the combination of major trauma (Injury Severity Score [ISS] > 15) and variable periods of immobility. Specific aims were to: 1) develop a conceptual model that illustrates physiological and psychological alterations that occur after injury and subsequent immobility, and their association with skeletal muscle responses and recovery; 2) evaluate daily measures of skeletal muscle strength (bicep and quadricep) using dynamometry and skeletal muscle (rectus femoris and biceps brachii) muscle thickness measured with ultrasound in patients after major trauma; and 3) assess the predictive ability of anxiety and …

Sarcopenia, Obesity, And Natural Killer Cell Immune Senescence In Aging: Altered Cytokine Levels As A Common Mechanism, Charles T. Lutz, Lebris S. Quinn

Pathology and Laboratory Medicine Faculty Publications

Human aging is characterized by both physical and physiological frailty. A key feature of frailty, sarcopenia is the age-associated decline in skeletal muscle mass, strength, and endurance that characterize even the healthy elderly. Increases in adiposity, particularly in visceral adipose tissue, are almost universal in aging individuals and can contribute to sarcopenia and insulin resistance by increasing levels of inflammatory cytokines known collectively as adipokines. Aging also is associated with declines in adaptive and innate immunity, known as immune senescence, which are risk factors for cancer and all-cause mortality. The cytokine interleukin-15 (IL-15) is highly expressed in skeletal muscle tissue …