RESUMO
Maca, Lepidium meyenii Walpers (Brassicaceae), is an annual herbaceous plant native to the high plateaus of the Peruvian central Andes. Its underground storage hypocotyls have been a traditional medicinal agent and dietary staple since pre-Columbian times. Reported properties include energizing and fertility-enhancing effects. Published reports have focused on the benzylalkamides (macamides) present in dry hypocotyls as one of the main bioactive components. Macamides are secondary amides formed by benzylamine and a fatty acid moiety, with varying hydrocarbon chain lengths and degree of unsaturation. Although it has been assumed that they are usually present in fresh undamaged tissues, analyses show them to be essentially absent from them. However, hypocotyls dried by traditional Andean postharvest practices or industrial oven drying contain up to 800µgg(-1) dry wt (2.3µmolg(-1) dry wt) of macamides. In this study, the generation of macamides and their putative precursors were studied during nine-week traditional drying trials at 4200m altitude and in ovens under laboratory conditions. Freeze-thaw cycles in the open field during drying result in tissue maceration and release of free fatty acids from storage and membrane lipids up to levels of 1200µgg(-1) dry wt (4.3µmolg(-1) dry wt). Endogenous metabolism of the isothiocyanates generated from glucosinolate hydrolysis during drying results in maximal benzylamine values of 4300µgg(-1) dry wt (40.2µmolg(-1) dry wt). Pearson correlation coefficients of the accumulation profiles of benzylamine and free fatty acid to that of macamides showed good values of 0.898 and 0.934, respectively, suggesting that both provide sufficient substrate for amide synthesis during the drying process.
Assuntos
Lepidium/química , Alcamidas Poli-Insaturadas/isolamento & purificação , Humanos , Hipocótilo/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peru , Fitoterapia , Extratos Vegetais/uso terapêutico , Alcamidas Poli-Insaturadas/químicaRESUMO
PURPOSE: To evaluate the benzylamine oxidase (BzAO), a tissue enzyme located in the middle tunica of the blood vessels specifically in the smooth muscle, in neoplastic and normal fragments removed of surgical specimens resected from patients with advanced gastric adenocarcinoma. METHODS: Were included in the study 24 patients (18 males and 6 female, mean age of 55,4 years). Considering the localization of the gastric tumours, 11 were in the antrum, 9 in the body, 2 in the cardia, 1 in the antrum and body and 1 in the fundus. Patients were submitted to total gastrectomy (12 cases) and to subtotal gastrectomy (12 patients) with D2 lymphadenectomy. The findings of BzAO were correlated with age, sex, localization, hystopatological type and the surgery performed. RESULTS: The enzymatic activity in normal tissues varied from 22,9 muM to 111 muM (média de 57,1), however, in neoplastic tissues the activity were higher and varied from 35,5 muM to 148 muM (média de 70,7). Statistical analysis using the t student test showed significant differences (standard deviation = 2.373 and p = 0.0263, p 0.05). CONCLUSION: The enzymatic activity were significant in the gastric tumours fragments, suggesting that there are a correlation between the BzAO and the angiogenesis, and therefore the possibility of utilization the antiangiogenic therapies to cause the inhibition of the tumor growth and metastases formation.
OBJETIVO: Realizar dosagens da benzilamino-oxidase (BzAO), uma enzima tissular localizada na túnica média dos vasos sanguíneos, mais precisamente no músculo liso, em fragmentos tumorais e não tumorais de peças cirúrgicas ressecadas de portadores de adenocarcinoma gástrico avançado. MÉTODOS: Foram incluídos no estudo 24 doentes (18 masculinos e seis femininos com média de idade de 55,4 anos). Quanto à localização do tumor, eram 11 do antro gástrico, nove do corpo, dois da cárdia, um do corpo e antro e um do fundo, sendo que 12 doentes foram submetidos a gastrectomia subtotal e os demais a gastrectomia total com esplenectomia, todos com linfadenectomia a D2. As dosagens de BzAO foram correlacionadas com idade , sexo , tempo de história da doença, local do tumor no estômago, tipo histopatólogico e cirurgia realizada. RESULTADOS: A atividade enzimática da BzAO nos tecidos gástricos normais variou de 22,9 miM a 111 miM (média de 57,1), sendo superior nos tecidos tumorais em todos os casos, variando de 35,5 miM a 148 miM (média de 70,7). A análise estatística pelo teste t de student mostrou diferença significativa entre as duas dosagens (desvio padrão de 2,373 e p = 0,0263, portanto p 0,05). CONCLUSÃO: As dosagens de BzAO foram mais elevadas nos fragmentos tumorais gástricos, sugerindo existir correlação entre a BzAO e a angiogênese, e, portanto, a possibilidade de utilização de terapias antiangiogênicas que atuem inibindo o crescimento tumoral e metastático.