RESUMO
Aulacoscelinae beetles have an ancient relationship with cycads (Cycadophyta: Zamiaceae), which contain highly toxic azoxyglycoside (AZG) compounds. How these "primitive" leaf beetles deal with such host-derived compounds remains largely unknown. Collections were made of adult Aulacoscelis appendiculata from Zamia cf. elegantissima in Panama, A. vogti from Dioon edule in Mexico, and Janbechynea paradoxa from Zamia boliviana in Bolivia. Total AZG levels were quantified in both cycad leaves and adult beetles by high performance liquid chromatography (HPLC). On average, cycad leaves contained between 0.5-0.8% AZG (frozen weight, FW), while adult beetles feeding on the same leaves contained even higher levels of the compounds (average 0.9-1.5% FW). High AZG levels were isolated from reflex bleeding secreted at the leg joints when beetles were disturbed. Nuclear magnetic resonance and mass spectroscopy identified two AZGs, cycasin and macrozamin, in the reflex bleeding; this is the first account of potentially plant-derived compounds in secretions of the Aulacoscelinae. These data as well as the basal phylogenetic position of the Aulacoscelinae suggest that sequestration of plant secondary metabolites appeared early in leaf beetle evolution.
Assuntos
Secreções Corporais/química , Besouros/química , Folhas de Planta/química , Zamiaceae/química , Animais , Evolução Biológica , Bolívia , Cromatografia Líquida de Alta Pressão , Cicasina/isolamento & purificação , Feminino , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Acetato de Metilazoximetanol/análogos & derivados , Acetato de Metilazoximetanol/isolamento & purificação , México , PanamáRESUMO
Six compounds were isolated from Rhizoma Heterosmilacis Japonicae. They were identified as beta-sitosterol (I) dau-costerol (II),3,3',5,5'-tetrahydroxy-4'-methoxystilbene (III), naringenin (IV), alpha-L-butylsorbopyranoside (V) and macrozamin (VI). The compounds III, IV, V and VI were isolated from this genus for the first time.
Assuntos
Flavanonas/isolamento & purificação , Liliaceae/química , Plantas Medicinais/química , Sitosteroides/isolamento & purificação , Flavanonas/química , Malpighiaceae , Acetato de Metilazoximetanol/análogos & derivados , Acetato de Metilazoximetanol/química , Acetato de Metilazoximetanol/isolamento & purificação , Estrutura Molecular , Tubérculos/química , Sitosteroides/química , Espectrofotometria Ultravioleta/métodosAssuntos
Encéfalo/metabolismo , Cycas , Acetato de Metilazoximetanol/análogos & derivados , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , alfa-Sinucleína/metabolismo , Esclerose Lateral Amiotrófica/induzido quimicamente , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Encéfalo/efeitos dos fármacos , Humanos , Acetato de Metilazoximetanol/isolamento & purificação , Acetato de Metilazoximetanol/toxicidade , Camundongos , Mutagênicos/isolamento & purificação , Mutagênicos/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologiaRESUMO
Chromatographic methods have been developed which allow the separation and identification of azomethane (AM), azoxymethane (AOM), and methylazoxymethanol (MAM). These methods have been applied to the analysis of bile, urine, and the exhaled air of rats treated with the 14C--labeled colon carcinogen 1,2-dimethylhydrazine (DMH) to provide evidence that AM, AOM, and MAM are indeed metabolites of DMH. Investigations into the metabolism and mode of action of DMH and its derivatives by other workers are briefly summarized and reviewed.