Nucleophilic Defense Against PM Toxicity (NEAT Trial)

NCT03314987 | Completed Results DMC

• 2 other identifiers: 20.02585R01ES019217
• Study Type: interventional
• Target: 299
• Locations: 1 country
• Sites: 1

Brief Summary

Carnosine is a naturally occurring peptide found in high levels in skeletal muscle and the brain and is also available commercially as a dietary supplement. Since carnosine has anti-oxidant properties and air pollution exposure induces a state of oxidative stress, the purpose of this study is to see if those taking carnosine as a dietary supplement are protected from air pollution-induced oxidative stress and adverse cardiovascular outcomes.

Conditions

Air Pollution Toxicity

Keywords

air pollution; oxidative stress; intervention

Outcome Measures

Primary Outcomes (1)

• Endothelial Progenitor Cells

  circulating pro-angiogenic cells

  3 months

Secondary Outcomes (3)

• Augmentation Index

  3 months

• Endothelial Microparticles

  Samples were collected from each participant at baseline, after ~6wk of intervention, and after ~12wk of intervention. Measurement will be performed on archived samples once assay is in place.

• Platelet Monocyte Aggregates

  3 months

Study Arms (2)

intervention group

ACTIVE COMPARATOR

Each participant will be given a daily oral dose of 2 grams of carnosine for 12 weeks

Dietary Supplement: L-carnosine

placebo group

PLACEBO COMPARATOR

Each participant will be given a daily oral dose of 2 grams of placebo for 12 weeks

Other: placebo

Interventions

L-carnosine DIETARY_SUPPLEMENT

a naturally occurring di-peptide

intervention group

placebo OTHER

an identically appearing supplement

placebo group

Eligibility Criteria

• Age: 22 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Individuals between 22-65 years of age of either gender and all ethnicities,
• All genders and all ethnicities
• Residing in or near the Louisville metropolitan area
• Consumes some type of meat/fish at least once a month during the past 3 months
• Carnosine levels below the median level of the population
• Agrees to complete all study visits and follow study intervention regimen
• Will be living in the study area throughout the study period, with no more than 1 week away from the study area.

You may not qualify if:

• Consumed any dietary supplement more than 3 times per week in the past 4 weeks (one month)
• Current / ongoing treatment for substance abuse
• Currently undergoing treatment or have conditions which may cause participant to be immunosuppressed
• Diseases Affecting Peripheral Cell Count (i.e. Autoimmune Diseases - Hashimoto, Rheumatoid Arthritis, SLE, Rheumatoid Arthritis, Sjogren syndrome, Ankylosing Spondylitis, Takayasu arteritis, Kawasaki disease, Polyarteritis nodosa.)
• Diseases Affecting Bone Marrow capacity
• Diagnosis of any active cancer
• Recent organ / kidney transplant or replacement (Active/Long-Term Medications)
• Type 1 Diabetes Mellitus
• Untreated thyroid disease
• Untreated anemia
• Current acute infections (Influenza, fever, etc.)
• HIV positive status
• Active/current Hepatitis HepA, HepB or HepC or in past 6 months
• Currently or planning to be Pregnant / lactating
• Prisoners / vulnerable populations

Sponsors & Collaborators

• University of Louisville: lead
• National Institute of Environmental Health Sciences (NIEHS): collaborator

Study Sites (1)

Clinical Trials Unit

Louisville, Kentucky, 40202, United States

Location

Related Publications (5)

• O'Toole TE, Hellmann J, Wheat L, Haberzettl P, Lee J, Conklin DJ, Bhatnagar A, Pope CA 3rd. Episodic exposure to fine particulate air pollution decreases circulating levels of endothelial progenitor cells. Circ Res. 2010 Jul 23;107(2):200-3. doi: 10.1161/CIRCRESAHA.110.222679. Epub 2010 Jul 1.

  PMID: 20595651 BACKGROUND

• Barski OA, Xie Z, Baba SP, Sithu SD, Agarwal A, Cai J, Bhatnagar A, Srivastava S. Dietary carnosine prevents early atherosclerotic lesion formation in apolipoprotein E-null mice. Arterioscler Thromb Vasc Biol. 2013 Jun;33(6):1162-70. doi: 10.1161/ATVBAHA.112.300572. Epub 2013 Apr 4.

  PMID: 23559625 RESULT

• Pope CA 3rd, Bhatnagar A, McCracken JP, Abplanalp W, Conklin DJ, O'Toole T. Exposure to Fine Particulate Air Pollution Is Associated With Endothelial Injury and Systemic Inflammation. Circ Res. 2016 Nov 11;119(11):1204-1214. doi: 10.1161/CIRCRESAHA.116.309279. Epub 2016 Oct 25.

  PMID: 27780829 RESULT

• Baba SP, Amraotkar AR, Hoetker D, Gao H, Gomes D, Zhao J, Wempe MF, Rice PJ, DeFilippis AP, Rai SN, Pope CA 3rd, Bhatnagar A, O'Toole TE. Evaluation of supplementary carnosine accumulation and distribution: an initial analysis of participants in the Nucleophilic Defense Against PM Toxicity (NEAT) clinical trial. Amino Acids. 2024 Aug 31;56(1):55. doi: 10.1007/s00726-024-03414-5.

  PMID: 39215872 DERIVED

• O'Toole TE, Amraotkar AA, DeFilippis AP, Rai SN, Keith RJ, Baba SP, Lorkiewicz P, Crandell CE, Pariser GL, Wingard CJ, Pope Iii CA, Bhatnagar A. Protocol to assess the efficacy of carnosine supplementation in mitigating the adverse cardiovascular responses to particulate matter (PM) exposure: the Nucleophilic Defense Against PM Toxicity (NEAT) trial. BMJ Open. 2020 Dec 28;10(12):e039118. doi: 10.1136/bmjopen-2020-039118.

  PMID: 33372072 DERIVED

MeSH Terms

Interventions

Carnosine

Intervention Hierarchy (Ancestors)

Neuropeptides; Peptides; Amino Acids, Peptides, and Proteins; Dipeptides; Oligopeptides; Nerve Tissue Proteins; Proteins

Results Point of Contact

• Title: Dr. Timothy O'Toole Associate Professor
• Organization: University of Louisville

tim.otoole@louisville.edu

15024190808

Study Officials

• Timothy E. O'Toole

  University of Louisville

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: double blind (participant, investigator)
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: placebo controlled, randomized, double-blind

Study Record Dates

• First Submitted: October 16, 2017
• First Posted: October 19, 2017
• Study Start: April 1, 2018
• Primary Completion: November 1, 2022
• Study Completion: November 1, 2022
• Last Updated: January 6, 2026
• Results First Posted: June 18, 2024

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)