Clinical Trial Summary
One of the greatest challenges faced by older adults is maintaining physical function and
strength with aging. Deterioration of skeletal muscle with aging leads to loss of mobility,
decreased quality of life, and ultimately loss of independence. Skeletal muscle deterioration
with aging is multifactorial, with a key factor being impaired skeletal muscle regeneration
following damage. Muscle regeneration is a multistep process that requires a viable
population of skeletal muscle specific progenitor cells (MPCs). MPCs reside in the skeletal
muscle in a dormant state until activated by stress or injury cues. Upon activation, MPCs
divide, commit to the muscle cell lineage, and fuse to form new multinucleated cells or
repair damaged muscle cells. In older adults this regenerative process is impaired, which
amplifies skeletal muscle deterioration. The investigators demonstrated that the ability of
MPCs to divide (proliferate) is reduced, while MPC death is elevated in MPCs from healthy
older adults. Further, the investigators have demonstrated that impaired nutrient metabolism,
cellular inflammation, and oxidative stress are key mechanisms in this age-related disruption
of MPC proliferation and overall skeletal muscle health. Therapies that improve the
regenerative process and nutrient metabolism as well as attenuate oxidative stress and
inflammation are necessary to improve overall skeletal muscle health of older adults.
Blueberries have properties that the investigators hypothesize will improve the proliferative
capacity (increase cell division and reduce cell death) of MPCs. Additionally, the
investigators hypothesize that consumption of blueberries will improve skeletal muscle
regeneration in the aging population via improved nutrient metabolism, attenuated cellular
inflammation, and reduction of oxidative stress. The hypotheses will be tested using a
dietary blueberry intervention. Serum from our human subjects [blueberry enriched diet
(BED)-serum] will be collected and used to treat primary human MPCs. Ultimately, the
investigators hypothesize that a blueberry enriched diet provides an ideal, natural therapy
to improve MPC proliferative capacity, which is necessary to attenuate skeletal muscle
deterioration.