The Role of Brain Lactate Metabolism in Neuroprotection During Healthy Aging

NCT07731451 | Not Yet Recruiting Early Phase 1 DMC

• 1 other identifier: 2396277
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

The brain's primary source of fuel is glucose. Unfortunately, the brain's ability to use glucose declines during normal aging. This decline in brain glucose metabolism makes it vulnerable to cognitive impairment and Alzheimer's disease. The brain can use another fuel source - lactate - which becomes available to the brain during exercise. The investigators have discovered that when lactate fuels the brain, brain glucose metabolism also improves. Essentially, from a metabolic angle, the brain appears younger. Recently, the investigators have shown that lactate - even in the absence of exercise - stimulates this beneficial effect on the brain. The investigators propose to compare the effects of lactate in healthy young and older adults to test whether these beneficial lactate-mediated effects persist throughout the lifespan, thereby providing a blueprint to restore youthful brain glucose metabolism.

Conditions

Aging Well; Aging

Keywords

brain metabolism; lactate; exercise; aging

Outcome Measures

Primary Outcomes (1)

• Cerebral metabolism

  Lactate, glucose and oxygen metabolism via stable isotope tracers and Fick method using arterial and internal jugular venous blood sampling in combination with cerebral blood flow via ultrasound. These will be quantified as rates in grams/minute or mililiters/minute.

  -Pre-intervention in rested state -During intervention when lactate is experimentally elevated -After recovery from intervention

Secondary Outcomes (2)

• Brain-specific biomarkers

  -Pre-intervention in rested state -During intervention when lactate is experimentally elevated -After recovery from intervention

• Cognitive function

  -Pre-intervention in rested state -During intervention when lactate is experimentally elevated -After recovery from intervention

Study Arms (2)

Passive lactate

ACTIVE COMPARATOR

Circulating lactate will be elevated via infusion

Biological: Sodium lactate infusion

Active lactate

EXPERIMENTAL

Circulating lactate will be elevated via exercise

Other: Exercise-induced hyperlactatemia

Interventions

Sodium lactate infusion BIOLOGICAL

Sodium lactate will be infused to target circulating concentrations between 4-6 mmol/L

Passive lactate

Exercise-induced hyperlactatemia OTHER

Cycling will be performed at an intensity to increase circulating lactate to 4-6 mmol/L

Active lactate

Eligibility Criteria

• Age: 20 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Meet the American College of Sports Medicine (ACSM) physical activity guidelines for moderate-intensity aerobic activity, i.e., 150+ minutes of moderate or 75+ minutes of rigorous aerobic activity.
• The older cohort must have adhered to these physical activity guidelines for 30+ years.
• "Good" or "Excellent" aerobic fitness category based on ACSM standardized maximal aerobic power (V̇O2max) values for age and sex.

You may not qualify if:

• Significant carotid plaque will be excluded via ultrasound assessment.
• Evidence of mild cognitive impairment (MCI)
• Personal complaints of memory deficits, clinical diagnosis, or evidence from the NIH ToolBox ®V3 will be considered signs of MCI.
• known allergy to Lidocaine also cannot participate.

Sponsors & Collaborators

• Northern Arizona University: lead

Study Sites (1)

Northern Arizona University Dept of Biological Sciences

Flagstaff, Arizona, 86011, United States

Location

MeSH Terms

Conditions

Motor Activity

Condition Hierarchy (Ancestors)

Behavior

Central Study Contacts

TRAVIS GIBBONS, PhD

CONTACT

17785836976; travis.gibbons@nau.edu

Tinna Traustadottir, PhD

CONTACT

9282558768; tinna.traustadottir@nau.edu

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: Repeated measures cross-over

Study Record Dates

• First Submitted: July 16, 2026
• First Posted: July 28, 2026
• Study Start (Estimated): January 1, 2027
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2029
• Last Updated: July 28, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)