RESUMO
A new type aporphine-benzylisoquinoline alkaloid leptofumarine (1) was isolated from Leptopyrum fumarioides L. The structure of 1 was elucidated based on spectroscopic evidence. Leptofumarine together with the previously isolated leptopyrine (2) were evaluated for their effect on macrophages and bone marrow (BM) cells in vitro. Both alkaloids inhibited cytokine production by LPS-stimulated peritoneal macrophages. Leptopyrine suppressed osteoclast and osteoblast formation, while leptofumarine affected only osteoblastogenesis.
Assuntos
Alcaloides , Ranunculaceae , Macrófagos , Estrutura Molecular , Componentes Aéreos da PlantaRESUMO
A new type of isoquinoline alkaloid leptopyrine was isolated from the aerial parts of Leptopyrum fumarioides L. (Ranunculaceae) of Mongolian origin. The known alkaloids protopine and thalifoline were isolated for the first time from this the species. All structures were established by physical and spectral analyses.
Assuntos
Alcaloides/química , Isoquinolinas/química , Ranunculaceae/química , Alcaloides/isolamento & purificação , Benzofenantridinas/química , Benzofenantridinas/isolamento & purificação , Alcaloides de Berberina/química , Alcaloides de Berberina/isolamento & purificação , Isoquinolinas/isolamento & purificação , Estrutura Molecular , Componentes Aéreos da Planta/químicaRESUMO
Twelve steroidal alkaloids were isolated from four populations of Veratrum lobelianum Bernh. and Veratrum nigrum L. Full NMR data for veralosinine (1), and extensive 1H NMR data for veralosine (3) and teinemine (5) are presented here for the first time. (+/-)-15-O-(2-Methylbutyroyl)germine (10) is undescribed up to now. The antiproliferative activities of veranigrine, veralosinine, and neogermitrine have shown that they are a perspective for further studies.
Assuntos
Divisão Celular/efeitos dos fármacos , Alcaloides de Veratrum/isolamento & purificação , Veratrum/química , Animais , Bulgária , Leucemia L5178/patologia , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Camundongos , Modelos Moleculares , Mongólia , Fitosteróis/farmacologia , Alcaloides de Veratrum/química , Alcaloides de Veratrum/farmacologiaRESUMO
Phase II detoxification enzymes are responsible for the detoxification and elimination of activated carcinogens, and thus act as important biomarkers for chemoprevention. In this study, we tested the chemopreventive activity of taxifolin, a flavanon compound purified from a mongolian medicinal plant, by measuring quinone reductase (QR) activity in HCT 116 cells. Taxifolin induced significant QR activity, but displayed relatively low cytotoxicity in cells (chemoprevention index=5.75). To identify the target genes regulated by taxifolin, DNA microarray was performed with a 3K human cancer chip containing 3096 human genes associated with carcinogenesis. Significant analysis of microarray (SAM) revealed 428 differentially expressed (DE) genes as statistically significant, with a false discovery rate (FDR) of 57.2% (delta=0.3366). Sixty-five genes, including a few detoxification enzymes (NQO1, GSTM1) and an antioxidant enzyme (TXNRD1), were up-regulated and 363 genes were down-regulated in the presence of 60 microM taxifolin. In view of the finding that selected genes of interest contained antioxidant response element (ARE), we hypothesize that taxifolin modulates chemopreventive genes through activation of the ARE. Transient transfection experiments using the ARE QR-CAT construct demonstrate that taxifolin significantly activates ARE, but not xenobiotic response element (XRE). In conclusion, taxifolin acts as a potential chemopreventive agent by regulating genes via an ARE-dependent mechanism.
