Bioavailability of SPMs in Obese Humans

Purpose: Specialized pro-resolving mediators (SPMs) are a superfamily of lipid metabolites, predominantly derived from the n-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic (EPA) and docosahexaenoic acids (DHA). Previous research has established that obese mice and humans have lower circulating levels of SPMs relative to lean controls. In this study, SPMs will be administered as a dietary supplement to obese human subjects to establish: 1) their bioavailability in plasma, serum and peripheral blood mononuclear cells (PBMCs) and 2) their effects on immune cell abundance and in vitro antibody production. The rationale for focusing on immune cells is that SPMs may be targeting their abundance and phenotype. This study does not intend to make any health or health-related claims.

Participants: A total of 24 (n=12 men + 12 women) obese (BMI 30-40 kg/m2) euglycemic and pre-diabetic subjects (fasting glucose 70-125 mg/dL or HbA1c of 5.7-6.4%) aged 50-65 years will be recruited by Dr. Erik Butler from the UNC Family Medicine Center in Chapel Hill.

Procedures (methods): This is a non-randomized uncontrolled clinical trial. The study will provide the intervention 'SPM Active' provided by Metagenics. All subjects will be advised to take 4 capsules per day (2 capsules with breakfast and 2 capsules with dinner) of 'SPM Active' for 4 weeks total. Each capsule contains 145 mg of SPMs for a total daily dose of 580 mg. Fasting blood will be drawn pre- and post-intervention using phlebotomy available under the direction of Dr. Butler. The scientific approach will rely on mass-spectrometry based metabololipidomics, immunophenotyping with flow cytometry, and anthropomorphic/blood pressure/BMI measurements (anthropometric measures are only intended for use in statistical analysis for confounding variables).

Inclusion criteria

• 24 (n=12 male + 12 female) obese (BMI 30-40 kg/m^2) subjects with age 50-65 years who are euglycemic and pre-diabetic (i.e. fasting glucose 70-125 mg/dL or HbA1c of 5.7-6.4%).
• Only post-menopausal females will be recruited in the female cohort to reduce the confounding effects of estrogen on lipid metabolism during supplementation.

Exclusion criteria

• Those with fasting glucose values > 126 mg/dL or known type 2 diabetes
• Females who are pre-menopausal, pregnant, planning to become pregnant, breastfeeding or lactating
• Subjects consuming n-3 PUFA supplements in the last 3 months prior to enrollment, high consumption of fatty fish (>2 servings per week), and subjects with active autoimmune disease, liver disease, coagulopathy, hypothyroidism, known allergy to fish or shellfish, inability to give informed consent, or taking anticoagulants (e.g. warfarin and direct-acting anticoagulants), those taking estrogen or testosterone, and anyone taking daily aspirin, NSAIDs, or active asthma medications.
• Subjects receiving immunomodulatory or immunosuppressant therapy (corticosteroids or monoclonal antibodies) in the 4 weeks prior to study enrollment, and subjects with known active malignancy or undergoing treatment for malignancy will be excluded.
• Subjects who test positive for COVID-19 or have tested positive in the past will be excluded. Those who report COVID-19 or flu-like symptoms will be excluded, as well as those that fail to pass COVID-19 screening at baseline.