A Study of Gamma Tocopherol-enriched Supplement on Lower Airway Responses to Inhaled Wood Smoke in Healthy Adults

Particulate matter (PM) is a leading cause of respiratory tract and cardiovascular disease in
the United States and world-wide. Wood smoke particles (WSP) derived from wildland and other
fires account for a significant fraction of ambient air PM. Health effects associated with
WSP include acute bronchitis, asthma exacerbation, pneumonia, cough and systemic
inflammation. While these effects are seen in both healthy and asthmatic individuals, many
studies indicate that asthmatics have increased susceptibility to the effects of WSP. The
investigators have developed a 500 μg/m3 WSP exposure protocol (levels similar to those
encountered by firefighters and residents in close proximity to wildland burn sites) that
induces airway and systemic inflammation in healthy volunteers. As with other pollutants,
these inflammatory responses modulate non-specific bronchial reactivity (NSBR), inflammatory
cell recruitment to the airways (primarily neutrophils), and potentially cardiovascular
function.

The investigators have focused on gamma tocopherol (γT) as a nutritional intervention to
prevent inflammatory responses to air pollutants such as WSP. Building on animal and in vitro
preclinical studies, the investigators have established that 1400 mg/day of oral γT-enriched
supplement for 7 and 14 days in healthy volunteers and mild asthmatics, respectively,
inhibited neutrophil influx into the airways, reduced production of sputum mucins, and
improved mucociliary clearance following challenge with inhaled endotoxin, another common
component of PM. The findings occurred in the context of significantly increased plasma
concentrations of γT and its active metabolite
2,7,8-trimethyl-2-(β-Carboxy-Ethyl)-6-Hydroxychroman (γ-CEHC). Given the findings in these
early phase clinical trials, γT supplementation is an attractive approach to prevent
WSP-induced adverse health effects. The investigators propose to use γT supplementation in a
human model of WSP inhalation to mitigate key features of airway inflammation: inflammatory
cell recruitment, production of inflammatory cytokines and mucous, and changes in airway
physiology.

Gamma tocopherol will be administered in softgel form, with each softgel containing 700 mg of
tocopherols, 89.5% of which is d-gamma tocopherol. Subjects will consume two softgels by
mouth once daily for 7 days. This dosing regimen was chosen based on the results of the
investigators' previous early phase clinical trials examining the impact of gamma tocopherol
on lipopolysaccharide (LPS) -induced airway inflammation in healthy adults and adults with
asthma. These studies tested a 7 and 14 day course of treatment, respectively, and found
similar plasma concentrations of γT and active metabolites in both studies. Furthermore, the
investigators showed in both studies that γT significantly reduced LPS-induced sputum
neutrophilia compared to placebo. Based on the previous findings, the investigators will now
study the efficacy of γT for mitigating WSP-induced airway inflammation.

Inclusion Criteria:

1. Age 18-45 years, inclusive, of both genders

2. Negative pregnancy test for females who are not s/p hysterectomy with oophorectomy

3. Forced expiratory volume at one second (FEV1) of at least 75% of predicted (without
use of bronchodilating medications for 12 hours), consistent with lung function of
persons with no more than mild intermittent or mild persistent asthma.

4. Oxygen saturation of <93% and blood pressure within the following limits: (Systolic
between 150-85 mmHg, Diastolic between 90-50 mmHg).

5. Ability to provide an induced sputum sample.

6. Subject must demonstrate a ≥10% increase in sputum neutrophils following inhaled WSP
exposure, when compared to baseline sputum (to be completed in a separate protocol).

7. Ability/willingness to discontinue inhaled corticosteroids, montelukast, and cromolyn
for 2 weeks without increased symptoms or increased need for beta agonist rescue
medication prior to screening and through the course of the study.

Exclusion Criteria

Patients who meet any of these criteria are not eligible for enrollment as study
participants:

1. Clinical contraindications:

1. Any chronic medical condition considered by the PI as a contraindication to the
exposure study including significant cardiovascular disease, diabetes, chronic
renal disease, chronic thyroid disease, history of chronic
infections/immunodeficiency.

2. Viral upper respiratory tract infection within 4 weeks of challenge.

3. Any acute infection requiring antibiotics within 4 weeks of exposure or fever of
unknown origin within 4 weeks of challenge.

4. Abnormal physical findings at the baseline visit, including but not limited to
abnormalities on auscultation, temperature of 37.8° C, Systolic BP > 150mm Hg or
< 85 mm Hg; or Diastolic BP > 90 mm Hg or < 50 mm Hg, or pulse oximetry
saturation reading less than 93%.

5. Physician directed emergency treatment for an asthma exacerbation within the
preceding 12 months.

6. Moderate or severe asthma

7. Exacerbation of asthma more than 2x/weeks which would be characteristic of a
person with moderate or severe persistent asthma as outlined in the current
National Asthma Education and Prevention Program (NAEPP) guidelines for diagnosis
and management of asthma

8. Daily requirement for albuterol due to asthma symptoms (cough, wheeze, chest
tightness) which would be characteristic of a person with moderate or severe
persistent asthma as outlined in the current NHLBI guidelines for diagnosis and
management of asthma (not to include prophylactic use of albuterol prior to
exercise).

9. Nighttime symptoms of cough or wheeze greater than 1x/week at baseline (not
during a clearly recognized viral induced asthma exacerbation) which would be
characteristic of a person of moderate or severe persistent asthma as outlined in
the current NHLBI guidelines for the diagnosis and management of asthma.

10. History of intubation for asthma

11. If there is a history of allergic rhinitis, subjects must be asymptomatic of
allergic rhinitis at the time of study enrollment.

12. Mental illness or history of drug or alcohol abuse that, in the opinion of the
investigator, would interfere with the participant's ability to comply with study
requirements.

13. Cigarette smoking > 1 pack per month

14. Unwillingness to use reliable contraception if sexually active (IUD, birth
control pills/patch, condoms).

15. Abnormal prothrombin time (PT) or activated partial thromboplastin time (aPTT)
values at screening or during the treatment period. Normal values will be those
published by the clinical lab (Labcorp, INC).

16. Use of immunosuppressive or anticoagulant medications including routine use of
NSAIDS. Oral contraceptives are acceptable, as are Antidepressants and other
medications may be permitted if, in the opinion of the investigator, the
medication will not interfere with the study procedures or compromise safety and
if the dosage has been stable for 1 month.

17. Orthopedic injuries or impediments that would preclude bicycle or treadmill
exercise.

18. Inability to avoid NSAIDS, Multivitamins, Vitamin C or E or herbal supplements.

19. Allergy/sensitivity to study drugs or their formulations

20. Known hypersensitivity to methacholine or to other parasympathomimetic agents

21. Unwillingness to avoid coffee, tea, cola drinks, chocolate, or other foods
containing caffeine after midnight on the days that methacholine challenge
testing is to be performed.

2. Pregnant/nursing women and children (< 18 years as this is age of majority in North
Carolina) will also be excluded since the risks associated with woodsmoke exposure to
the fetus or child, respectively, are unknown and cannot be justified for this
non-therapeutic protocol. Individuals over 45 years of age will not be included due to
the increased possibility of co-morbidities and need for prohibited medications.

3. Inability or unwillingness of a participant to give written informed consent.