Skeletal Muscle Characteristics Long-living Dwarf Mice in Response to High Fat Diet

Authors

• Landon Schumacher
• Matthew Johnston
• Jaspreet Osan
• Holly Brown-Borg

Files

Description

Introduction: The effects of high fat diet (HFD; 60% kcal: fat) on skeletal muscle in mice with postnatal growth hormone deficiency is relatively unknown. We compared the tibialis anterior (TA) muscle from middle aged female Ames Dwarf and Wildtype mice fed HFD for 16 weeks and standard diet (STD; 10%: fat) to see the impacts of a HFD on inflammation and fibrotic formation in the musculature.   Methodology: Mice were euthanized after diet duration (age 10-12 months), and TAs were collected and frozen in OCT for cross-sectional cryosection. Ten um thick muscle was fixed to slides and stained with Oil Red-O (ORO), Picrosirius red (PSR), and Hematoxylin and Eosin (H&E). Images of the tissue were processed via ImageJ fibrosis (PSR) and centrally located nuclei (H&E).   Results: Compared to control fed mice, no difference was observed between the Dwarf and Wildtype mice and diet in fibrotic infiltration or centrally located nuclei within the TA. Dwarf mice display significant increases in fibrotic area when fed the STD compared to the dwarf on HFD. Diet did not seem to have an effect on interior fibrosis on Wildtype mice. When compared to dwarf mice on STD, wildtype mice on STD show significantly more centrally located nuclei. The Wildtype mice on STD also had significantly more centrally located nuclei than wildtype mice on HFD.   Conclusions: These findings indicate that diet does not play a large part in the formation of fibrosis or centrally located nuclei when comparing middle aged female Ames Dwarfs and Wildtypes. The reduction in fibrosis between the dwarfs on HFD compared to dwarfs on STD may be due to extracellular matrix remodeling resulting in a reduction in collagen protein between cells. Previous work in our lab has shown Wildtype mice display increased inflammation and fibrotic infiltration with age when on STD, and we think that HFD will exacerbate these findings.

Publication Date

5-7-2026

Document Type

Poster

City

Grand Forks, ND

Disciplines

Biology

Comments

Presented at the Spring 2026 Arts & Sciences UNDergraduate Showcase in Grand Forks, ND, May 7, 2025.

Recommended Citation

Schumacher, Landon; Johnston, Matthew; Osan, Jaspreet; and Brown-Borg, Holly, "Skeletal Muscle Characteristics Long-living Dwarf Mice in Response to High Fat Diet" (2026). Arts & Sciences Undergraduate Showcase. 29.
https://commons.und.edu/as-showcase/29