title: n-3 PUFA improves fatty acid composition, prevents palmitate-induced apoptosis, and differentially modifies B cell cytokine secretion in vitro and ex vivo.
abstract: n-3 polyunsaturated fatty acids (PUFAs) modify T-cell activation, in part by remodeling lipid composition; however, the relationship between n-3 PUFA and B-cell activation is unknown. Here we tested this relationship in vitro and ex vivo by measuring upregulation of B-cell surface molecules, the percentage of cells activated, and cytokine secreted in response to lipopolysaccharide (LPS) activation. In vitro, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) improved the membrane n-6/n-3 PUFA ratio, and DHA lowered interleukin (IL)-6 secretion; overall, n-3 PUFAs did not suppress B-cell activation compared with BSA, oleate, or elaidate treatment. Palmitate treatment suppressed the percentage of B cells activated through lipoapoptosis, which was differentially prevented by cosupplementing cells with MUFAs and PUFAs. Ex vivo, we tested the hypothesis with mice fed a control or high-fat saturated, hydrogenated, MUFA or n-3 PUFA diets. n-3 PUFAs had no effect on the percentage of B cells activated. Unexpectedly, the n-3 PUFA diet increased B-cell CD69 surface expression, IL-6 and IFNgamma secretion, and it significantly increased body weight gain. Overall, we propose that changes in lipid composition with n-3 PUFA and suppression of lymphocyte activation is not universal. The study highlights that high-fat n-3 PUFA diets can promote pro-inflammatory responses, at least from one cell type.
authors.affiliation: Department of Biochemistry and Molecular Biology, East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, 600 Moye Blvd, Brody 5S-18, Greenville, NC 27834, USA.
authors.forename: Benjamin Drew
authors.initials: BD
authors.lastname: Rockett
authors.forename: Muhammad
authors.initials: M
authors.lastname: Salameh
authors.forename: Kristen
authors.initials: K
authors.lastname: Carraway
authors.forename: Kaitlin
authors.initials: K
authors.lastname: Morrison
authors.forename: Saame Raza
authors.initials: SR
authors.lastname: Shaikh
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D001081:Apyrase / Q000378:metabolism; D001402:B-Lymphocytes / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism*; D004041:Dietary Fats / Q000494:pharmacology; D005227:Fatty Acids / Q000737:chemistry* / Q000378:metabolism; D005229:Fatty Acids, Monounsaturated / Q000494:pharmacology; D015525:Fatty Acids, Omega-3 / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009929:Organ Size / Q000187:drug effects; D010168:Palmitates / Q000494:pharmacology*; D013154:Spleen / Q000033:anatomy & histology / Q000187:drug effects; D013997:Time Factors; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D015703:Antigens, CD; D016207:Cytokines; D004041:Dietary Fats; D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated; D015525:Fatty Acids, Omega-3; D010168:Palmitates; D001081:Apyrase; C067869:CD39 antigen