# Role of immune cells on the growth and recovery of aging muscle

> **NIH NIH R21** · UTAH STATE HIGHER EDUCATION SYSTEM--UNIVERSITY OF UTAH · 2020 · $190,625

## Abstract

Abstract
Older adults are prone to experience periods of muscle disuse resulting in muscle atrophy and weakness.
Moreover, muscle recovery following a disuse event is impaired in older adults. Therefore, a high priority in the
face of a rapidly growing aging population is a need to further understand the cellular mechanisms behind
impaired muscle regrowth with aging. Macrophages and other immune cell populations (e.g., T-cells) are of
critical importance to optimally restore muscle size following a period of disuse, however, their role under such
conditions in aging skeletal muscle has surprisingly not been elucidated. Therefore, using a well-established
mouse model of muscle disuse and regrowth, we have produced compelling preliminary data demonstrating
impaired muscle regrowth in aged mice and this is accompanied by an altered macrophage immune response
and recruitment in skeletal muscle during recovery. In the current proposal, we have proposed to conduct an
extensive time course of the muscle macrophage (and other immune cells) response in old and young mice
during recovery from disuse. We will also determine if inhibiting macrophage recruitment in young mice will result
in a phenotype characteristic of old mice during recovery from disuse. We will utilize combined unique
approaches of FACS and single cell RNA sequencing to extensively address these questions. These data will
be foundational for additional mechanistic studies investigating upstream mediators of macrophage and other
immune cell responses during recovery from disuse while also using novel immunotherapies to optimize muscle
recovery in older muscle.

## Key facts

- **NIH application ID:** 9889020
- **Project number:** 5R21AG062923-02
- **Recipient organization:** UTAH STATE HIGHER EDUCATION SYSTEM--UNIVERSITY OF UTAH
- **Principal Investigator:** Micah J Drummond
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $190,625
- **Award type:** 5
- **Project period:** 2019-03-15 → 2022-02-28

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9889020

## Citation

> US National Institutes of Health, RePORTER application 9889020, Role of immune cells on the growth and recovery of aging muscle (5R21AG062923-02). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/9889020. Licensed CC0.

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