title: Dietary supplementation with purified citrus limonin glucoside does not alter ex vivo functions of circulating T lymphocytes or monocytes in overweight/obese human adults.
abstract: Overweight/obesity is associated with chronic inflammation and impairs both innate and adaptive immune responses. Limonoids found in citrus fruits decreased cell proliferation and inflammation in animal studies. We hypothesized that limonin glucoside (LG) supplementation in vivo will decrease the ex vivo proliferation of T cells and the production of inflammatory cytokines by monocytes and T cells. In a double-blind, randomized, cross-over study, 10 overweight/obese human subjects were served purified LG or placebo drinks for 56 days each to determine the effects of LG on immune cell functions. The percentage of CD14+CD36+ cells in whole blood was analyzed by flow cytometry. Peripheral blood mononuclear cells were isolated and activated with CD3 plus CD28 antibodies (T-lymphocyte activation) or lipopolysaccharide (monocyte activation). Interferon γ, tumor necrosis factor α, interleukin (IL) 2, IL-4, and IL-10 were measured in supernatants from activated T cells. Supernatants from activated monocytes were analyzed for the production of tumor necrosis factor α, IL-1β, and IL-6. Peripheral blood mononuclear cells were prestained with PKH dye and activated with CD3 plus CD28 antibodies to determine the proliferative responses of CD4+ and CD8+ T lymphocytes by flow cytometry. No differences were observed for CD14+CD36+ monocyte populations, T-cell proliferation, or the production of T cell and monocyte cytokines between the 2 treatments. Thus, LG supplementation in vivo did not affect ex vivo functions of T cells and monocytes, whereas it decreased several circulating markers of hepatic inflammation as we previously reported.
authors.affiliation: Western Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Davis, CA 95616-8683, USA.
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Zunino
authors.affiliation: Western Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Davis, CA 95616-8683, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Storms
authors.affiliation: Western Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Davis, CA 95616-8683, USA.
authors.forename: Tammy L
authors.initials: TL
authors.lastname: Freytag
authors.affiliation: Western Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Davis, CA 95616-8683, USA.
authors.forename: Yuriko C
authors.initials: YC
authors.lastname: Adkins
authors.affiliation: Department of Nutrition, University of California, Davis, CA 95616, USA.
authors.forename: Ellen L
authors.initials: EL
authors.lastname: Bonnel
authors.affiliation: Western Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Davis, CA 95616-8683, USA.
authors.forename: Leslie R
authors.initials: LR
authors.lastname: Woodhouse
authors.affiliation: Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Albany, CA 94710, USA.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Breksa
authors.affiliation: Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Albany, CA 94710, USA.
authors.forename: Gary D
authors.initials: GD
authors.lastname: Manners
authors.affiliation: Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Albany, CA 94710, USA.
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Mackey
authors.affiliation: Western Human Nutrition Research Center, Agricultural Research Service, United States Department of Agriculture, Davis, CA 95616-8683, USA. Electronic address: darshan.kelley@ars.usda.gov.
authors.forename: Darshan S
authors.initials: DS
authors.lastname: Kelley
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use*; D001628:Beverages / Q000009:adverse effects; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D015992:Body Mass Index; D049109:Cell Proliferation; D002478:Cells, Cultured; D002957:Citrus / Q000737:chemistry*; D018592:Cross-Over Studies; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D005638:Fruit / Q000737:chemistry; D005960:Glucosides / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use; D006505:Hepatitis / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D036701:Limonins / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use*; D008297:Male; D024821:Metabolic Syndrome / Q000209:etiology / Q000517:prevention & control; D008875:Middle Aged; D009000:Monocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D009765:Obesity / Q000178:diet therapy / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D050177:Overweight / Q000178:diet therapy* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D015415:Biomarkers; D005960:Glucosides; D036701:Limonins
keywords: Citrus limonin glucoside; Cytokines; Monocytes; Overweight/obese humans; T lymphocytes