RESUMO
The original version of this Article contained an error in the spelling of the authors J. H. Joly and N. A. Graham, which were incorrectly given as J. Jolly and N. Graham. Additionally, the affiliation of both authors with 'Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089' and N. A. Graham with 'Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089' was inadvertently omitted. This has now been corrected in both the PDF and HTML versions of the Article.
RESUMO
Centella asiatica is widely used as a medicinal plant due to accumulation of the ursane-type triterpene saponins asiaticoside and madecassoside. The molecular structure of both compounds suggests that they are biosynthesized from α-amyrin via three hydroxylations, and the respective Cyt P450-dependent monooxygenases (P450 enzymes) oxidizing the C-28 and C-2α positions have been reported. However, a third enzyme hydroxylating C-23 remained elusive. We previously identified 40,064 unique sequences in the transcriptome of C. asiatica elicited by methyl jasmonate, and among them we have now found 149 unigenes encoding putative P450 enzymes. In this set, 23 full-length cDNAs were recognized, 13 of which belonged to P450 subfamilies previously implicated in secondary metabolism. Four of these genes were highly expressed in response to jasmonate treatment, especially in leaves, in accordance with the accumulation patterns of asiaticoside. The functions of these candidate genes were tested using heterologous expression in yeast cells. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that yeast expressing only the oxidosqualene synthase CaDDS produced the asiaticoside precursor α-amyrin (along with its isomer ß-amyrin), while yeast co-expressing CaDDS and CYP716A83 also contained ursolic acid along with oleanolic acid. This P450 enzyme thus acts as a multifunctional triterpenoid C-28 oxidase converting amyrins into corresponding triterpenoid acids. Finally, yeast strains co-expressing CaDDS, CYP716A83 and CYP714E19 produced hederagenin and 23-hydroxyursolic acid, showing that CYP714E19 is a multifunctional triterpenoid oxidase catalyzing the C-23 hydroxylation of oleanolic acid and ursolic acid. Overall, our results demonstrate that CaDDS, CYP716A83 and CYP714E19 are C. asiatica enzymes catalyzing consecutive steps in asiaticoside biosynthesis.
Assuntos
Centella/enzimologia , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Plantas/metabolismo , Triterpenos/metabolismo , Vias Biossintéticas , Centella/genética , Sistema Enzimático do Citocromo P-450/genética , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ácido Oleanólico/metabolismo , Filogenia , Proteínas de Plantas/genética , Plantas Medicinais , Triterpenos/químicaRESUMO
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Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Hipersensibilidade a Drogas/imunologia , Rivaroxabana/efeitos adversos , Rivaroxabana/uso terapêutico , Eosinofilia/complicações , Eosinofilia/imunologia , Corticosteroides/uso terapêutico , Tomografia Computadorizada de Emissão/instrumentação , Tomografia Computadorizada de Emissão/métodos , Tomografia Computadorizada de Emissão , Hipóxia/complicaçõesRESUMO
One popular strategy to improve the acceptance and efficacy of oral liquid supplements in long-term care is dispensing them during the medication pass, although few studies support its effectiveness. This study evaluated the impact of a supplement medication pass program on energy and nutrient consumption and weight in nursing home residents. Findings indicate that residents maintained their prestudy weight and had a 29% decrease in supplement energy intake, a 19% increase in food energy intake, and a 17% decrease in net energy intake (supplement plus food). Supplement and food protein intake remained stable. Over longer periods, this reduced energy consumption could lead to weight loss, so routine monitoring and periodic evaluations of resident intake (both food and supplement) are recommended to ensure residents are receiving and consuming adequate amounts of daily energy and nutrients.
Assuntos
Suplementos Nutricionais , Estado Nutricional , Idoso , Peso Corporal , Ingestão de Energia , Humanos , Assistência de Longa Duração , Casas de Saúde , Satisfação do PacienteRESUMO
This time the synthesis of some new derivatives obtained by the quaternary substitution of one of the heterocyclic nitrogen atoms and by reactions of dipolar cycloaddition is presented. The results of the tests on their antimicrobial and antiinflammatory actions are discussed.