title: Anthocyanin Extracted from Black Soybean Seed Coats Prevents Autoimmune Arthritis by Suppressing the Development of Th17 Cells and Synthesis of Proinflammatory Cytokines by Such Cells, via Inhibition of NF-κB.
abstract: BACKGROUND
  Oxidative stress plays a role in the pathogenesis of rheumatoid arthritis (RA). Anthocyanin is a plant antioxidant. We investigated the therapeutic effects of anthocyanin extracted from black soybean seed coats (AEBS) in a murine model of collagen-induced arthritis (CIA) and human peripheral blood mononuclear cells (PBMCs) and explored possible mechanisms by which AEBS might exert anti-arthritic effects.
  
  
  METHODS
  CIA was induced in DBA/1J mice. Cytokine levels were measured via enzyme-linked immunosorbent assays. Joints were assessed in terms of arthritis incidence, clinical arthritis scores, and histological features. The extent of oxidative stress in affected joints was determined by measuring the levels of nitrotyrosine and inducible nitric oxide synthase. NF-κB activity was assayed by measuring the ratio of phosphorylated IκB to total IκB via Western blotting. Th17 cells were stained with antibodies against CD4, IL-17, and STAT3. Osteoclast formation was assessed via TRAP staining and measurement of osteoclast-specific mRNA levels.
  
  
  RESULTS
  In the CIA model, AEBS decreased the incidence of arthritis, histological inflammation, cartilage scores, and oxidative stress. AEBS reduced the levels of proinflammatory cytokines in affected joints of CIA mice and suppressed NF-κB signaling. AEBS decreased Th17 cell numbers in spleen of CIA mice. Additionally, AEBS repressed differentiation of Th17 cells and expression of Th17-associated genes in vitro, in both splenocytes of naïve DBA/1J mice and human PBMCs. In vitro, the numbers of both human and mouse tartrate-resistant acid phosphatase+ (TRAP) multinucleated cells fell, in a dose-dependent manner, upon addition of AEBS.
  
  
  CONCLUSIONS
  The anti-arthritic effects of AEBS were associated with decreases in Th17 cell numbers, and the levels of proinflammatory cytokines synthesized by such cells, mediated via suppression of NF-κB signaling. Additionally, AEBS suppressed osteoclastogenesis and reduced oxidative stress levels.
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.|Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Hong Ki
authors.initials: HK
authors.lastname: Min
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Seung-Ye
authors.initials: SY
authors.lastname: Baek
authors.affiliation: Office of Clinical Development, Genexine Inc., Korea Bio Park, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Jung-Won
authors.initials: JW
authors.lastname: Woo
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Jin-Sil
authors.initials: JS
authors.lastname: Park
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Mi-La
authors.initials: ML
authors.lastname: Cho
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.|Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Lee
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.|Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Seung-Ki
authors.initials: SK
authors.lastname: Kwok
authors.affiliation: Catholic Integrative Medicine Research Institute, College of Medicine, The Catholic University of Korea, Seoul, South Korea.|Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Sae Woong
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Rheumatism Research Center, Catholic Research Institute of Medical Science, The Catholic University of Korea, Seoul, South Korea.|Division of Rheumatology, Department of Internal Medicine, School of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Sung-Hwan
authors.initials: SH
authors.lastname: Park
mesh_terms: D000818:Animals; D000872:Anthocyanins / Q000494:pharmacology*; D001169:Arthritis, Experimental / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D001327:Autoimmune Diseases / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D015153:Blotting, Western; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000633:toxicity; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D007124:Immunoenzyme Techniques; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D010010:Osteoclasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000737:chemistry; D015398:Signal Transduction / Q000187:drug effects; D013025:Glycine max / Q000737:chemistry; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D058504:Th17 Cells / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D016207:Cytokines; D016328:NF-kappa B; D010936:Plant Extracts; D012333:RNA, Messenger; D003094:Collagen