About

Steven Prior is a researcher with a focus on exercise physiology, vascular biology, and the effects of physical activity on cardiovascular and skeletal muscle health. His work extensively explores the impact of exercise training on mitochondrial quality control proteins, muscle perfusion, and systemic inflammation, particularly in the context of aging, peripheral arterial disease, and metabolic conditions such as type 2 diabetes. Prior's research also investigates the cellular and molecular mechanisms underlying exercise-induced adaptations, including the paracrine function of circulating angiogenic cells and the role of microRNAs in endothelial function and inflammation. His studies often involve both human and animal models to elucidate sex-specific and age-related differences in physiological responses to exercise and vascular stress. Through his contributions, Prior has advanced understanding of how exercise modulates vascular and muscular health, with implications for improving functional outcomes in clinical populations such as older adults, veterans, and individuals with chronic diseases.

Research topics

• Internal medicine
• Cardiology
• Medicine
• Endocrinology
• Surgery

Selected publications

• Group virtual nutrition and teaching kitchen intervention versus time/attention-matched health education curriculum control to improve dietary quality and social engagement among older Veterans with impaired mobility: a randomized controlled trial

  BMC Geriatrics · 2026-04-28

  articleOpen access

  Older Veterans with impaired mobility often face barriers to food shopping, meal preparation, and cooking that can contribute to poor diet quality and declining health. This randomized controlled trial will test whether a 12-week virtual nutrition and teaching kitchen program improves diet quality (Healthy Eating Index [HEI]), compared with time- and attention-matched contact-control group. We plan to enroll 180 Veterans ≥ 65 years of age with mobility limitations who will be randomized to an intervention or control group. Participants in the intervention group will attend one live, one-hour virtual session each week for 12 weeks, including cooking demonstrations, and tailored nutrition education, with adaptive equipment and occupational therapy guidance provided as needed. Control participants will attend matched group health education sessions focused on healthy aging. Outcome assessments occur at baseline, 3 months, and 6 months. The primary outcome is change in HEI score from baseline to 3 months. Secondary outcomes include change in HEI from 3 to 6 months, and changes in social isolation, loneliness, and health-related quality of life, physical function, body composition, and fear of falling from baseline to 3 months. Sample size calculations indicate that 73 participants per group will provide 80% power to detect a 5.5-point between-group difference in HEI, allowing for 20% attrition. This trial aims to provide evidence on effectiveness of a virtual nutrition and cooking program designed to improve diet quality and social connection in older adults with mobility impairments. We anticipate that this protocol will show that virtual nutrition education and cooking demonstrations is an efficacious strategy to improve diet that also has potential for scalability through implementation into existing health promotion programs. This trial was registered at ClinicalTrials.gov: NCT06726083 on 12/05/2024 (https://clinicaltrials.gov/study/NCT06726083). Two-arm RCT (N = 180; ≥65 years with mobility limitations) testing a 12-week virtual nutrition + teaching kitchen program (with produce delivery) vs. time/attention-matched health education curriculum control. Primary outcome is change in Healthy Eating Index (HEI) with assessments at baseline, after the 3-month intervention, and at 3 months post-intervention. Secondary outcomes include food literacy, health literacy, food insecurity, social isolation, health-related quality of life, frailty, body composition, and physical function. 6-month follow-up focus groups will assess sustained effects of the intervention.

  PublisherDOI

• Home-Based Exercise to Improve Functional Outcomes in Veterans With a Recently Healed Diabetic Foot Ulcer: Protocol for a Pilot Randomized Controlled Trial (Preprint)

  2025-01-15

  preprintOpen access

  <sec> <title>BACKGROUND</title> Foot ulcers are a common complication of diabetes, often resulting from peripheral neuropathy and inadvertent trauma. Poor healing is exacerbated by peripheral arterial disease and poor glycemic control. Off-loading, a key treatment, leads to prolonged immobility. Patients rarely regain baseline mobility. Mobility is crucial to improve glycemia, promote vascular health, and improve immobility as it leads to nursing home admissions. There is limited research on exercise during ulcer remission. </sec> <sec> <title>OBJECTIVE</title> This pilot study will assess the feasibility and acceptability of a home-based exercise regimen aimed at safely increasing mobility and function, focusing on improving lower extremity strength, tissue perfusion, and glycemic control. </sec> <sec> <title>METHODS</title> Veterans aged ≥50 years with a recently healed diabetic plantar foot ulcer receiving care in the US Department of Veterans Affairs (VA) Maryland Health Care System and enrolled in a remote temperature-sensing mat program will be eligible. Potential participants will be identified via administrative codes used for the Prevention of Amputation in Veterans Everywhere directive, as well as using the VA’s Podimetrics SmartMat dashboard. In this pilot study, 25 veterans will be randomized (in a 3:1 ratio) to a 12-week home-based exercise regimen or standard of care. Participants will undergo tests for gait speed, knee extension strength, cutaneous perfusion, and community mobility. The intervention group will participate in internet-based videoconference exercise classes twice a week led by the study team and home cycling 3 times a week. The control group will receive standard-of-care guidance. Outcome measures will include feasibility; acceptability; and changes in gait speed, physical activity levels, and strength. </sec> <sec> <title>RESULTS</title> This study was funded on July 1, 2024, with data collection planned from October 1, 2024, to March 31, 2026. The protocol was approved by the University of Maryland Institutional Review Board on May 13, 2024, and by the Baltimore VA Research and Development Committee on June 13, 2024. As of June 12, 2025, 12 participants have been enrolled in the study, and 6 (50%) participants have been randomized. Recruitment is expected to continue through December 2025. </sec> <sec> <title>CONCLUSIONS</title> This project has potential for clinical rehabilitation translation. If it is found to be feasible and acceptable, the exercise intervention will be tested in a future multisite randomized clinical trial to assess its impact on mobility, cardiovascular events, and ulcer recurrence. </sec> <sec> <title>CLINICALTRIAL</title> ClinicalTrials.gov NCT06312579; https://clinicaltrials.gov/ct2/show/NCT06312579 </sec> <sec> <title>INTERNATIONAL REGISTERED REPORT</title> DERR1-10.2196/71237 </sec>

  PublisherDOI

• Home-Based Exercise to Improve Functional Outcomes in Veterans With a Recently Healed Diabetic Foot Ulcer: Protocol for a Pilot Randomized Controlled Trial

  JMIR Research Protocols · 2025-08-12

  articleOpen access

  BACKGROUND: Foot ulcers are a common complication of diabetes, often resulting from peripheral neuropathy and inadvertent trauma. Poor healing is exacerbated by peripheral arterial disease and poor glycemic control. Off-loading, a key treatment, leads to prolonged immobility. Patients rarely regain baseline mobility. Mobility is crucial to improve glycemia, promote vascular health, and improve immobility as it leads to nursing home admissions. There is limited research on exercise during ulcer remission. OBJECTIVE: This pilot study will assess the feasibility and acceptability of a home-based exercise regimen aimed at safely increasing mobility and function, focusing on improving lower extremity strength, tissue perfusion, and glycemic control. METHODS: Veterans aged ≥50 years with a recently healed diabetic plantar foot ulcer receiving care in the US Department of Veterans Affairs (VA) Maryland Health Care System and enrolled in a remote temperature-sensing mat program will be eligible. Potential participants will be identified via administrative codes used for the Prevention of Amputation in Veterans Everywhere directive, as well as using the VA's Podimetrics SmartMat dashboard. In this pilot study, 25 veterans will be randomized (in a 3:1 ratio) to a 12-week home-based exercise regimen or standard of care. Participants will undergo tests for gait speed, knee extension strength, cutaneous perfusion, and community mobility. The intervention group will participate in internet-based videoconference exercise classes twice a week led by the study team and home cycling 3 times a week. The control group will receive standard-of-care guidance. Outcome measures will include feasibility; acceptability; and changes in gait speed, physical activity levels, and strength. RESULTS: This study was funded on July 1, 2024, with data collection planned from October 1, 2024, to March 31, 2026. The protocol was approved by the University of Maryland Institutional Review Board on May 13, 2024, and by the Baltimore VA Research and Development Committee on June 13, 2024. As of June 12, 2025, 12 participants have been enrolled in the study, and 6 (50%) participants have been randomized. Recruitment is expected to continue through December 2025. CONCLUSIONS: This project has potential for clinical rehabilitation translation. If it is found to be feasible and acceptable, the exercise intervention will be tested in a future multisite randomized clinical trial to assess its impact on mobility, cardiovascular events, and ulcer recurrence. TRIAL REGISTRATION: ClinicalTrials.gov NCT06312579; https://clinicaltrials.gov/ct2/show/NCT06312579. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/71237.

  PublisherDOI

• 6-months Of Low-and Moderate-intensity Supervised Exercise Is Associated With Improved Cognition In Healthy Older Adults

  Medicine & Science in Sports & Exercise · 2025-09-16

  article

  PURPOSE: Memory decline is an early indicator of cognitive impairment in aging adults, and research suggests regular exercise participation may help preserve memory function. This randomized clinical trial (NCT03727360) aimed to determine the effects of a 6-month supervised exercise intervention on cognitive function, particularly memory, in cognitively healthy and physically inactive older adults aged 60-89 years. METHOD: One hundred and six cognitively intact older adults were randomized into an experimental group (n = 55) and a control group (n = 51). Both groups participated in a progressive online group exercise regimen, beginning with 30-minute sessions twice a week and gradually increasing the frequency, duration, and intensity over 7 weeks to reach 60-minute sessions 4 times a week. The experimental group exercised at a higher intensity (80% of maximal heart rate). Cognitive function was assessed at baseline (BL) and after the 6-month (6 M) intervention using the Rey Auditory Verbal Learning Test (RAVLT) for memory and the Delis-Kaplan Executive Function System (D-KEFS) for executive function. Physical fitness was evaluated at each time point using 6-minute walk and graded exercise tests. Linear mixed effects models with TIME (BL vs. 6 M) and CONDITION (Experimental vs. Control) as fixed factors were employed to detect changes in memory and fitness from baseline to follow-up. RESULTS: There were no significant changes in the 6-minute walk or VO2max tests, but cognitive performance improved significantly across both groups. Notably, participants demonstrated substantial gains in the RAVLT (sum of trials 1-5) (df = 104, t = 2.09, p = 0.039) and D-KEFS free sorting task (df = 93.375, t = 3.462, p < 0.001). CONCLUSION: These findings suggest that a 6-month supervised exercise program can significantly enhance memory and executive function in healthy older adults, even in the absence of measurable improvements in fitness. Regular, structured exercise may be valuable to support cognitive health and potentially delay age-related cognitive decline. Supported by: NIH-NIA R01AG057552

  PublisherDOI

• Peripheral blood mononuclear cell number and paracrine function in responses to a 50‐km trail race: An exploratory study

  Physiological Reports · 2025-02-01

  articleOpen accessSenior authorCorresponding

  Peripheral blood mononuclear cells (PBMCs) represent a heterogeneous mix of cells with paracrine functions that may be altered following prolonged exercise. We determined the effect of ultramarathon running on PBMC paracrine function and PBMC subtype number. Recreational athletes participated in a 50 km ultramarathon. Blood was sampled from N = 7 at baseline, 10 km, 50 km, and 24 h post-race. PBMCs were isolated and cultured, and conditioned media was used for a HUVEC-based proliferation assay. CD31+, CD3+, and CD31+/CD3+ PBMCs were quantified at each time point. Proliferation increased from baseline to 50 km (p = 0.004) and was reduced from 50 km to 24 h post (p = 0.008). There was an increase in CD31+ PBMCs after 50 km (p = 0.014), returning to baseline at 24 h post-race (p = 0.246). CD3+ PBMC and CD31+/CD3+ PBMC numbers were reduced after 50 km (p = 0.001 and p = 0.002, respectively), returning to baseline levels 24 h post-race (p = 0.190 and p = 0.315, respectively). PBMC paracrine activity following a 50 km enhances endothelial cell proliferation. Alterations in PBMC subtypes after 50 km suggest a protective role of PBMCs in response to prolonged stresses of ultramarathon running.

  PublisherOA PDFDOI

• Rapid CE–MS with Real-Time Eco–AI Resolves Proteomic Heterogeneity Among Single Human Neutrophils

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-08-20 · 1 citations

  preprintOpen access

  ABSTRACT Single-cell proteomics by mass spectrometry is advancing rapidly, yet throughput and sensitivity remain limiting—particularly for small, protein-poor cell types such as neutrophils. As the most abundant circulating leukocytes in humans, neutrophils are central to immune defense and inflammation, but their proteomes comprehensive single-cell level characterization has only concurrently been reported 1 and remains limited. Here, we introduce a rapid capillary electrophoresis–mass spectrometry (CE–MS) platform, which integrates electrophoresis-correlative real-time data acquisition with sub-7-minute separations and artificial intelligence (AI)-based data processing software to achieve deep, high-throughput profiling. Using single-cell–equivalent HeLa digests, the Rapid Eco–AI platform identified ∼1,350 proteins from 300 pg and ∼835 proteins from 75 pg of input— approaching the complexity of a mammalian cell proteome. Applied to freshly isolated human neutrophils, the workflow identified 151 proteins from ∼2 pg of material, ∼3% of the total cell proteome. Analysis of 13 individual cells revealed marked functional heterogeneity across pathways of degranulation, neutrophil extracellular trap (NET) formation, chemotaxis, and innate immunity, with hierarchical clustering resolving at least four distinct proteomic subtypes. These results establish Rapid Eco–AI as a sensitive, scalable, and broadly applicable CE–MS approach for immune-cell phenotyping at single-cell and subcellular resolution, facilitating new research opportunities in systems immunology and clinical proteomics.

  PublisherOA PDFDOI

• Moderate chronic aortic constriction induces modest, sex-specific effects on rat hearts and skeletal muscle

  Current Research in Physiology · 2025-01-01

  articleOpen access

  Heart failure with preserved ejection fraction (HFpEF) accounts for ∼50 % of heart failure diagnoses, occurs in older individuals, is more prevalent in females than males, and includes hypertension as contributing factor. We sought to determine whether a long-term, moderate, transverse aortic constriction in male and female rats induces ventricular hypertrophy and preserved ejection fraction, changes in skeletal muscle mass and strength, and sex-specific differences in these outcomes, mimicking HFpEF. Transverse aortic constriction (TAC) surgery was performed on male and female rats at 4 weeks of age, and rats were sacrificed 40 weeks after surgery, following echocardiography and grip strength measures. Male TAC rats demonstrated a 12 % greater heart mass and 17 % higher heart to body mass ratio than Sham rats; however, these parameters did not differ between female TAC and Sham rats. TAC rats demonstrated a preserved ejection fraction, and TAC had no effect on skeletal muscle size or strength. In summary, male rats were more susceptible to TAC-induced pressure-overload hypertrophy than female rats, and this moderate constriction resulted in preserved ejection fraction despite a long time course. Collectively, these investigations reveal, in the absence of comorbidities, pressure overload produces modest, sex-specific effects in the myocardium and skeletal muscle.

  PublisherDOI

• Age and sex-specific changes in mitochondrial quality control in skeletal and cardiac muscle

  Frontiers in Aging · 2025-06-25 · 6 citations

  articleOpen access

  Introduction: Skeletal and cardiac muscle mitochondria exist in a dynamic reticulum that is maintained by a balance of mitochondrial biogenesis, fusion, fission, and mitophagy. This balance is crucial for adequate ATP production, and alterations in skeletal muscle mitochondria have been implicated in aging-associated declines in mitochondrial function. Methods: We sought to determine whether age and biological sex affect mitochondrial content [Complex IV (CIV)], biogenesis (PGC-1ɑ), fusion (MFN2, OPA1), fission (DRP1, FIS1), and mitophagy (Parkin, Pink1) markers in skeletal and cardiac muscle by assessing protein expression in tibialis anterior (TA) and ventricular tissue from 16 young (≤6 months) and 16 old (≥20 months) male and female Sprague-Dawley rats. Results: In the TA, CIV expression was 40% lower in old vs. young rats (p < 0.001), indicating lower mitochondrial content, and coincided with higher expression of Parkin (+4-fold, p < 0.001). Further, MFN2 expression was higher (+2-fold, p < 0.005) and DRP1 expression was lower (-40%, p = 0.014) in older rats. In cardiac muscle, mitochondrial content was maintained in old vs. young rats, and this occurred concomitantly with higher expression of both PGC-1ɑ and Parkin. MFN2 and OPA1 expression were also 1.2-5-fold higher in older rats (p < 0.05 for all). Largely, protein expression did not differ between male and female rats, with the exception of Pink1 and FIS1 expression in the TA. Discussion: Collectively, older skeletal and cardiac muscle demonstrated higher expression of fusion and mitophagy proteins, which indicates age alters the balance of biogenesis, fission, fusion, and mitophagy. This may, in turn, affect the ability to provide ATP to these metabolically active tissues.

  PublisherDOI

• Impacts of sarcopenia and resistance exercise training on mitochondrial quality control proteins

  The Journal of Frailty & Aging · 2025-10-01 · 3 citations

  articleOpen accessSenior author

  BACKGROUND: The progression of sarcopenia with aging may be related to mitochondrial dysfunction due in part to altered mitochondrial dynamics (fusion, fission, mitophagy, and biogenesis). Previous work has identified altered expression of proteins associated with these processes in with aging, but whether further changes occur in sarcopenia remains unclear. OBJECTIVES: The purpose of this study was to assess protein expression of markers of mitochondrial fusion (Mfn2, Opa1), fission (Drp1, Fis1), mitophagy (Parkin), biogenesis (PGC-1α), and content (Complex IV: CIV) in sarcopenic and non-sarcopenic older adults. We also determined whether resistance training affected skeletal muscle mitochondrial content and expression of mitochondrial quality control proteins in sarcopenic older adults. DESIGN: Longitudinal exercise training study, with cross-sectional baseline comparison. SETTING AND PARTICIPANTS: Ten older adults with mild-moderate sarcopenia, plus ten non-sarcopenic, matched older adults from Maryland, USA. INTERVENTION: Twelve-week resistance training. MEASUREMENTS: Strength, sarcopenic index (ALM/BMI: appendicular lean mass divided by body mass index), body composition, and mitochondrial morphology and protein expression in vastus lateralis muscle. RESULTS: No differences in protein expression were observed between sarcopenic and non-sarcopenic participants at baseline; however, ALM/BMI was inversely related to CIV expression (r = -0.55, P = 0.013) across all subjects. Similarly, lean body mass and ALM correlated inversely with expression of the fusion protein Opa1-S (r = -0.55 - -0.51, P ≤ 0.022). Resistance training increased strength in sarcopenic older adults by 13 % (P = 0.02), but this group's expression of mitochondrial quality control proteins was mostly unaltered. CONCLUSIONS: The presence of sarcopenia identified by ALM/BMI was not associated with changes in protein expression that are consistent with impaired mitochondrial dynamics beyond those changes that might occur with aging alone. While short-term resistance training increased strength in older adults with sarcopenia, this was not accompanied by changes in protein expression, with the possible exception of fusion protein Mfn2.

  PublisherDOI

• Age and Sex-Specific Changes in Mitochondrial Quality Control in Skeletal and Cardiac Muscle

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-01-20 · 1 citations

  preprintOpen access

  Abstract Skeletal and cardiac muscle mitochondria exist in a dynamic reticulum that is maintained by a balance of mitochondrial biogenesis, fusion, fission, and mitophagy. This balance is crucial for adequate ATP production, and alterations in skeletal muscle mitochondria have been implicated in aging-associated declines in mitochondrial function. We sought to determine whether age and biological sex affect mitochondrial content [Complex IV (CIV)], biogenesis (PGC-1ɑ), fusion (MFN2, OPA1), fission (DRP1, FIS1), and mitophagy (Parkin, Pink1) markers in skeletal and cardiac muscle by assessing protein expression in tibialis anterior (TA) and ventricular tissue from 16 young (≤6 months) and 16 old (≥20 months) male and female Sprague-Dawley rats. In the TA, CIV expression was 40% lower in old vs. young rats (p&lt;0.001), indicating lower mitochondrial content, and coincided with higher expression of Parkin (+4-fold, p&lt;0.001). Further, MFN2 expression was higher (+2-fold, p&lt;0.005) and Parkin was lower (-40%, p=0.014) in older rats. In cardiac muscle, mitochondrial content was maintained in old vs. young rats, and this occurred concomitantly with higher expression of both PGC-1ɑ and Parkin. MFN2 and OPA1 expression were also 1.2-5-fold higher in older rats (p&lt;0.05 for all). Largely, protein expression did not differ between male and female rats, with the exception of Pink1 and FIS1 expression in the TA. Collectively, older skeletal and cardiac muscle demonstrated higher expression of fusion and mitophagy proteins, which indicates age alters the balance of biogenesis, fission, fusion, and mitophagy. This may, in turn, affect the ability to provide ATP to these metabolically active tissues.

  PublisherDOI

Recent grants

• Exercise training, CACs, and vascular function in older veterans with IGT

  NIH · 2013–2017

• Post-revascularization rehabilitation to improve function in Veterans with PAD

  NIH · 2016–2018

• University of Maryland Aging Diversity and Professional Training (UM ADAPT II)

  NIH · $2.6M · 2013–2027

• NIH Grant K23AG040775

  NIH · $532k · 2017

Frequent coauthors

• Alice S. Ryan

  University of Maryland, Baltimore

  144 shared

• Leslie I. Katzel

  Geriatric Research Education and Clinical Center

  82 shared

• Rian Q. Landers‐Ramos

  80 shared

• James M. Hagberg

  University of Maryland, College Park

  78 shared

• Odessa Addison

  University of Maryland, Baltimore

  72 shared

• Jacob B. Blumenthal

  58 shared

• Charlene E. Hafer‐Macko

  University of Maryland, Baltimore

  46 shared

• Monica C. Serra

  44 shared

Awards & honors

• New Investigator Research Award, The Obesity Society (2007)
• Paul B. Beeson Scholar, NIH-NIA and the American Federation…
• Maryland Research Excellence Honoree, University of Maryland…
• Winston Family Honors Award, Faculty Mentor - Honors Thesis,…
• MPower Professor, University of Maryland Strategic Partnersh…