title: Red Blood Cell Docosapentaenoic Acid (DPA n-3) is Inversely Associated with Triglycerides and C-reactive Protein (CRP) in Healthy Adults and Dose-Dependently Increases Following n-3 Fatty Acid Supplementation.
abstract: The role of the long-chain omega-3 (n-3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in lipid metabolism and inflammation has been extensively studied; however, little is known about the relationship between docosapentaenoic acid (DPA, 22:5 n-3) and inflammation and triglycerides (TG). We evaluated whether n-3 DPA content of red blood cells (RBC) was associated with markers of inflammation (interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and C-reactive protein (CRP) and fasting TG prior to n-3 supplementation in two studies (Study 1: n = 115, aged 20-44 years, body mass index (BMI) 20-30 kg/m2, TG = 34-176 mg/dL; Study 2: n = 28, aged 22-65 years, BMI 24-37 kg/m2, TG = 141-339 mg/dL). We also characterized the dose-response effects of n-3 fatty acid supplementation on RBC n-3 DPA after five months of supplementation with fish oil (Study 1: 0, 300, 600, 900, and 1800 mg/day EPA + DHA) and eight weeks of prescription n-3 ethyl esters (Study 2: 0, 850, and 3400 mg/day EPA + DHA). In Study 1, RBC n-3 DPA was inversely correlated with CRP (R2 = 36%, p < 0.001) and with fasting TG (r = -0.30, p = 0.001). The latter finding was replicated in Study 2 (r = -0.33, p = 0.04). In both studies, n-3 supplementation significantly increased RBC n-3 DPA dose-dependently. Relative increases were greater for Study 1, with increases of 29%-61% vs. 14%-26% for Study 2. The associations between RBC n-3 DPA, CRP, and fasting TG may have important implications for the prevention of atherosclerosis and chronic inflammatory diseases and warrant further study.
authors.affiliation: Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA. aus164@psu.edu.
authors.forename: Ann C
authors.initials: AC
authors.lastname: Skulas-Ray
authors.affiliation: Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA. mike.flock@gmail.com.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Flock
authors.affiliation: Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA. ckr129@psu.edu.
authors.forename: Chesney K
authors.initials: CK
authors.lastname: Richter
authors.affiliation: OmegaQuant Analytics, LLC, Sioux Falls, SD 57106, USA. Bill@omegaquant.com.
authors.forename: William S
authors.initials: WS
authors.lastname: Harris
authors.affiliation: Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA. sgw2@psu.edu.|Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA 16802, USA. sgw2@psu.edu.
authors.forename: Sheila G
authors.initials: SG
authors.lastname: West
authors.affiliation: Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA. pmk3@psu.edu.
authors.forename: Penny M
authors.initials: PM
authors.lastname: Kris-Etherton
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism*; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D015118:Eicosapentaenoic Acid / Q000008:administration & dosage; D004912:Erythrocytes / Q000187:drug effects*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage*; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D005395:Fish Oils; D015850:Interleukin-6; D014280:Triglycerides; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein; D015118:Eicosapentaenoic Acid; C026219:docosapentaenoic acid
keywords: DPA; fish oil; inflammation; marine omega-3 fatty acids