title: Petatewalide B, a novel compound from Petasites japonicus with anti-allergic activity.
abstract: BACKGROUND
  The giant butterbur Petasites japonicus is used to treat asthma and allergic diseases in traditional Korean, Japanese, and Chinese medicine.
  
  
  OBJECTIVE
  To elucidate the anti-allergic effect of Petasites genus, we studied effects of several compounds from Petasites japonicus leaves and found a novel bakkenolide-type sesquiterpine. In the present study, anti-allergic and anti-inflammatory effects of the new compound was examined using in vivo and in vitro experiments.
  
  
  METHODS
  The novel compound was isolated from Petasites japonicus leaves and named petatewalide B. Antigen-induced degranulation and Ca(2+) mobilization were measured in RBL-2H3 mast cells by measuring β-hexosaminidase activity and fluorescence change of Ca(2+) probe, fura-2. Induction of inducible nitric oxide synthase and cyclooxygenase 2 was measured by Western blotting in peritoneal macrophages. In addition, ovalbumin-induced asthma model was used for in vivo efficacy test of petatewalide B. Membrane potential was estimated by measuring fluorescence change of DiBAC in C6 glioma cells.
  
  
  RESULTS
  Petatewalide B inhibited the antigen-induced degranulation of β-hexosaminidase in RBL-2H3 mast cells, but did not affect antigen-induced Ca(2+) increase in the cells. Petatewalide B also showed inhibition of the LPS-induced induction of iNOS, but not COX-2 in mouse peritoneal macrophages. Nitric oxide production was also inhibited by petatewalide B in macrophages. In the ovalbumin-induced asthma model, petatewalide B strongly inhibited accumulations of eosinophils, macrophages, and lymphocytes in bronchoalveolar lavage fluid. Petatewalide B increased the membrane potential of C6 glioma cells in a concentration-dependent manner.
  
  
  CONCLUSIONS
  Petatewalide B from Petasites genus not only has anti-allergic and anti-inflammatory effects but also induces a transient increase of membrane potential in C6 glioma cells.
authors.affiliation: Department of Horticultural Bioscience, College of Natural Resources & Life Science, Pusan National University, Miryang-si, Gyeongsangnam 627-706, Republic of Korea.
authors.forename: Young-Whan
authors.initials: YW
authors.lastname: Choi
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Kyoung-Pil
authors.initials: KP
authors.lastname: Lee
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Saeromi
authors.initials: S
authors.lastname: Kang
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Soo-Jin
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Hyung Ryong
authors.initials: HR
authors.lastname: Moon
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Jee H
authors.initials: JH
authors.lastname: Jung
authors.affiliation: Department of Horticultural Bioscience, College of Natural Resources & Life Science, Pusan National University, Miryang-si, Gyeongsangnam 627-706, Republic of Korea.
authors.forename: Young-Geun
authors.initials: YG
authors.lastname: Lee
authors.affiliation: Molecular Inflammation Research Center for Aging Intervention (MRCA) and College of Pharmacy, Pusan National University, Busan 609-735, Republic of Korea. Electronic address: imds@pusan.ac.kr.
authors.forename: Dong-Soon
authors.initials: DS
authors.lastname: Im
mesh_terms: D000818:Animals; D018926:Anti-Allergic Agents / Q000737:chemistry* / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000494:pharmacology; D001249:Asthma / Q000188:drug therapy*; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000378:metabolism; D008297:Male; D008407:Mast Cells / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D036901:Petasites / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D012717:Sesquiterpenes / Q000737:chemistry / Q000494:pharmacology; D001619:beta-N-Acetylhexosaminidases / Q000378:metabolism
chemical_list: D018926:Anti-Allergic Agents; D000893:Anti-Inflammatory Agents; D010936:Plant Extracts; D012717:Sesquiterpenes; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; D001619:beta-N-Acetylhexosaminidases; D002118:Calcium
keywords: Anti-allergy; Anti-inflammation; Degranulation; Macrophage; Mast cell; Membrane potential; Petatewalide B