title: Flowers from Kalanchoe pinnata are a rich source of T cell-suppressive flavonoids.
abstract: The chemical composition and immunosuppressive potential of the flowers from Kalanchoe pinnata (Crassulaceae) were investigated. We found that the aqueous flower extract was more active than the leaf extract in inhibiting murine T cell mitogenesis in vitro. Flavonoids isolated from the flower extract were identified and quantitated based on NMR and HPLC-DAD-MS analysis, respectively. Along with quercetin, four quercetin glycosyl conjugates were obtained, including quercetin 3-O-beta-D-glucuronopyranoside and quercetin 3-O-beta-D-glucopyranoside, which are described for the first time in K. pinnata. All flavonoids inhibited murine T cell mitogenesis and IL-2 and IL-4 production without cell toxicity. This is the first report on the pharmacological activity of flowers of a Kalanchoe species, which are not used for curative purposes. Our findings show that K. pinnata flowers are a rich source of T-suppressive flavonoids that may be therapeutically useful against inflammatory diseases.
authors.affiliation: Núcleo de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Marcela A S
authors.initials: MA
authors.lastname: Coutinho
authors.forename: Michelle F
authors.initials: MF
authors.lastname: Muzitano
authors.forename: Elaine A
authors.initials: EA
authors.lastname: Cruz
authors.forename: Maria C
authors.initials: MC
authors.lastname: Bergonzi
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Kaiser
authors.forename: Luzineide W
authors.initials: LW
authors.lastname: Tinoco
authors.forename: Anna R
authors.initials: AR
authors.lastname: Bilia
authors.forename: Franco F
authors.initials: FF
authors.lastname: Vincieric
authors.forename: Bartira
authors.initials: B
authors.lastname: Rossi-Bergmann
authors.forename: Sônia S
authors.initials: SS
authors.lastname: Costa
mesh_terms: D000818:Animals; D016764:Cell Polarity; D049109:Cell Proliferation / Q000187:drug effects; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology*; D035264:Flowers / Q000737:chemistry*; D005786:Gene Expression Regulation / Q000187:drug effects; D007166:Immunosuppressive Agents / Q000737:chemistry / Q000494:pharmacology; D031962:Kalanchoe / Q000737:chemistry*; D008198:Lymph Nodes / Q000166:cytology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000187:drug effects*
chemical_list: D016207:Cytokines; D005419:Flavonoids; D007166:Immunosuppressive Agents