title: Stimulatory effect of apigenin-6-C-beta-L-fucopyranoside on insulin secretion and glycogen synthesis.
abstract: In vivo and in vitro treatments were carried out to investigate the effects of apigenin-6-C-beta-L-fucopyranoside (1), isolated from Averrhoa carambola L. (Oxalidaceae), on serum glucose and insulin levels in hyperglycemic rats as well as its effect on glycogen synthesis in normal rat soleus muscle. Apigenin-6-C-beta-L-fucopyranoside showed an acute effect on blood glucose lowering in hyperglycemic rats and stimulated glucose-induced insulin secretion. A stimulatory effect of 1 on glycogen synthesis was observed when muscles were incubated with this flavonoid and also its effect was completely nullified by pre-treatment with insulin signal transduction inhibitors. Taking this into account, the MAPK-PP1 and PI3K-GSK3 pathways are involved in the apigenin-6-C-beta-L-fucopyranoside-induced increase in glycogen synthesis in muscle. This study provides evidence for dual effects of apigenin-6-C-beta-L-fucopyranoside as an antihyperglycemic (insulin secretion) as well as an insulinomimetic (glycogen synthesis) agent.
authors.affiliation: Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário, Bairro Trindade, Florianópolis, SC, Brazil.
authors.forename: Luisa Helena
authors.initials: LH
authors.lastname: Cazarolli
authors.forename: Poliane
authors.initials: P
authors.lastname: Folador
authors.forename: Henrique Hunger
authors.initials: HH
authors.lastname: Moresco
authors.forename: Inês Maria Costa
authors.initials: IM
authors.lastname: Brighente
authors.forename: Moacir Geraldo
authors.initials: MG
authors.lastname: Pizzolatti
authors.forename: Fátima Regina M Barreto
authors.initials: FR
authors.lastname: Silva
mesh_terms: D000818:Animals; D047310:Apigenin / Q000302:isolation & purification / Q000627:therapeutic use*; D029624:Ferns / Q000737:chemistry*; D006003:Glycogen / Q000378:metabolism*; D006027:Glycosides / Q000302:isolation & purification / Q000627:therapeutic use*; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000627:therapeutic use*; D007328:Insulin / Q000378:metabolism*; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects; D010936:Plant Extracts / Q000302:isolation & purification / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar
chemical_list: D006027:Glycosides; D007004:Hypoglycemic Agents; D007328:Insulin; D010936:Plant Extracts; C546678:apigenin-6-C-beta-L-fucopyranoside; D047310:Apigenin; D006003:Glycogen