Ryan Armbruster
Bioengineering Pre-Doctoral Student
Contact Information
Tel:(215) 898-9357
Fax: (215) 573-2113
Email: ryan.armbruster@pennmedicine.upenn.edu
Education
Ph.D. Candidate, Bioengineering, University of Pennsylvania, 2022–Present
B.S. Biochemistry, Saint Joseph’s University, Philadelphia, PA, 2020
Bio:
Ryan Armbruster is a PhD student in the Department of Bioengineering at the University of Pennsylvania, where he joined the Center for Advanced Metabolic Imaging in Precision Medicine (CAMIPM) in 2022. His research focuses on developing and applying advanced, multi-nuclear MR methods to non-invasively study energy metabolism in human skeletal muscle and brain, with an emphasis on clinical translatability.
His primary work centers on creatine chemical exchange saturation transfer (CrCEST) MRI and proton MR spectroscopic imaging (¹H-MRSI) at 7T to interrogate oxidative phosphorylation capacity and metabolic fluxes in skeletal muscle. A key application of this work is characterizing the metabolic effects of GLP-1 receptor agonist therapies in individuals with obesity, including changes in intramyocellular lipids (IMCL), acetylcarnitine, and creatine kinetics. In parallel, he develops methods to reproducibly measure lactate in the healthy human brain using ¹H-MRS at 3T, exploring lactate as a non-invasive window into cerebral energy metabolism.
Beyond proton MRS, Ryan’s interest spans to multinuclear approaches including phosphorus-31 (³¹P) MRS for direct measurement of high-energy phosphate metabolism, and deuterium (²H) MRS for tracking the downstream metabolism of labeled substrates. This multinuclear strategy positions his research at the intersection of metabolic methodology development and translational applications in metabolic disease.
Interests
Energy metabolism; CrCEST MRI; ¹H-MRS/MRSI; ³¹P MRS; ²H MRS; skeletal muscle oxidative phosphorylation; intramyocellular lipids; acetylcarnitine; lactate; multinuclear spectroscopy; 7T MRI/MRS; GLP-1 receptor agonist therapy; translational metabolic imaging
Peer-Reviewed Publications
1. Armbruster RR, Kumar D, Benyard B, Jacobs P, Khandavilli A, Liu F, Nanga RPR, McCormack S, Cappola AR, Wilson N, Reddy R. Personalized and muscle-specific OXPHOS measurement with integrated CrCEST MRI and proton MR spectroscopy. Nature Communications. 2024;15(1):5387.
2. Armbruster RR, Kumar D, Wilson NE, Reddy R. Proton MRI and MRSI as a superior methodology to assess oxidative phosphorylation. Academic Radiology. 2025. doi:10.1016/j.acra.2025.11.034. [Article in Press]
3. Armbruster R, Wilson N, Elliott MA, Liu F, Benyard B, Jacobs P, Swain A, Nanga RPR, Reddy R. Repeatability of Lac+ measurements in healthy human brain at 3T. NMR in Biomedicine. 2024;37(9):e5158.
4. Soni ND, Swain A, Jacobs P, Juul H, Armbruster R, Nanga RPR, Nath K, Wiers C, Detre J, Reddy R. In vivo assessment of β-hydroxybutyrate metabolism in mouse brain using deuterium (²H) MRS. Magnetic Resonance in Medicine. 2023;90(1):259–268.
Most Recent Accepted Abstracts
2026
5. Armbruster R, Wilson N, Ergin A, Cappola AR, Amaro A, Reddy R. Lipid and acetyl carnitine differences measured before and after GLP-1 induced weight loss at 7T with ¹H-MRS. ISMRM; 2026. Abstract #03212.
6. Armbruster R, Wilson N, Frimpong Y, Cappola AR, Amaro A, Reddy R. CrCEST measures OXPHOS improvement and creatine decrease following GLP-1 induced weight loss at 7T. ISMRM; 2026. Abstract #04787.
7. Armbruster R, Wilson N, Reddy R. Blood flow significantly distorts measurement stability and recovery kinetics in single-voxel spectroscopy CrCEST. ISMRM; 2026. Abstract #06998.
2025
8. Armbruster RR, Wilson NE, Elliott MA, Swago S, Witschey WR, Reddy R. Homocarnosine editing in the human brain: repeatable brain pH measurements at 3T. ISMRM; May 2025. Abstract.
9. Armbruster RR, Elliott MA, Jacobs P, Benyard B, Wilson NE, Reddy R. Lac+ clearance measured in brain after exercise with ¹H-MRS. ISMRM MRS Study Group Workshop; 2025. Abstract and oral presentation.