RESUMO
In the present work, the MeOH extract from stem barks of Calophyllum brasiliense Cambess. (Clusiaceae) displayed activity against amastigote forms of Trypanosoma cruzi and Leishmania infantum and was subjected to a bioactivity-guided fractionation to give two related coumarins - calanolides E1 (1) and E2 (2). Compounds 1 and 2 were actives to T. cruzi with EC50 values of 12.1 and 8.2 µM, respectively. When tested against L. infantum, the EC50 values were 37.1 and 29.1 µM, respectively. Compound 2, corresponding to anti isomer, showed the best selectivity index (SI) with values >24.4 to T. cruzi and >6.9 to L. infantum in comparison to the syn isomer 1. Furthermore, using an in silico multi-parametric prediction, both compounds did not contain any PAINS sub-structures. Therefore, these data suggest that coumarins 1 and 2 may contribute as scaffolds for the design of novel drug candidates for leishmaniasis and Chagas disease.
Assuntos
Calophyllum , Clusiaceae , Leishmania infantum , Piranocumarinas , Trypanosoma cruzi , Cumarínicos/farmacologiaRESUMO
Citrus sinensis and Citrus limonia were obtained by germination from seeds, and isotopic-labeling experiments using d-[1-13C]glucose were performed with the seedlings. After 60 days, the seedlings were analyzed by high-performance liquid chromatography-ultraviolet-solid-phase extraction-nuclear magnetic resonance, data and the 13C enrichment patterns of xanthyletin and seselin indicated that the pyran ring was formed by the methylerythritol phosphate pathway and that the coumarin moiety was derived from the shikimate pathway in both compounds. This information regarding the biosynthetic pathway can be used to increase resistance against phytopathogens, because xanthyletin and seselin are reported to have antimicrobial activity on the growth of Xylella fastidiosa, which causes citrus variegated chlorosis in orange.
Assuntos
Marcação por Isótopo/métodos , Piranocumarinas/metabolismo , Isótopos de Carbono , Cromatografia Líquida de Alta Pressão , Citrus/metabolismo , Citrus sinensis/metabolismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Doenças das Plantas/microbiologia , Piranocumarinas/química , Piranocumarinas/isolamento & purificação , Ácido Chiquímico/metabolismo , Extração em Fase Sólida , Espectrofotometria Ultravioleta , Xylella/efeitos dos fármacosRESUMO
BACKGROUND: Calophyllum brasiliense is highlighted as an important resource of calanolides, which are dipyranocoumarins that inhibit the reverse transcriptase of human immunodeficiency virus type 1 (HIV-1 RT). Despite having great medicinal importance, enzymes involved in calanolide, biosynthesis and the pathway itself, are still largely unknown. Additionally, no genomic resources exist for this plant species. RESULTS: In this work, we first analyzed the transcriptome of C. brasiliense leaves, stem, and roots using a RNA-seq strategy, which provided a dataset for functional gene mining. According to the structures of the calanolides, putative biosynthetic pathways were proposed. Finally, candidate unigenes in the transcriptome dataset, potentially involved in umbelliferone and calanolide (angular pyranocoumarin) biosynthetic pathways, were screened using mainly homology-based BLAST and phylogenetic analyses. CONCLUSIONS: The unigene dataset that was generated in this study provides an important resource for further molecular studies of C. brasiliense, especially for functional analysis of candidate genes involved in the biosynthetic pathways of linear and angular pyranocoumarins.
Assuntos
Calophyllum/genética , Proteínas de Plantas/genética , Piranocumarinas/metabolismo , Calophyllum/classificação , Calophyllum/metabolismo , Perfilação da Expressão Gênica , Filogenia , Proteínas de Plantas/metabolismo , TranscriptomaRESUMO
Calophyllum species are sources of calanolides, which inhibit human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT). The hexane extract of the leaves from C. brasiliense collected in Soconusco, State of Chiapas, Mexico, analyzed by HPLC showed to contain apetalic acid, calanolides B, and C. It showed potent anti-HIV-1 RT inhibition (IC(50)=20.2 µg/ml), but was not toxic in mice (LD(50)=1.99 g/kg). The histological study of the mice treated at the highest dose revealed no alteration on hepatocytes, and an increase in the number of spleen megakaryocytes. These results suggest this extract is suitable to continue studies for developing a phytodrug against HIV-1.
Assuntos
Calophyllum/química , Transcriptase Reversa do HIV/antagonistas & inibidores , Isoflavonas/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Piranocumarinas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Animais , Calophyllum/efeitos adversos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/enzimologia , Hepatócitos/efeitos dos fármacos , Humanos , Isoflavonas/efeitos adversos , Isoflavonas/análise , Masculino , Megacariócitos/efeitos dos fármacos , México , Camundongos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Folhas de Planta , Piranocumarinas/efeitos adversos , Piranocumarinas/análise , Inibidores da Transcriptase Reversa/efeitos adversos , Inibidores da Transcriptase Reversa/análise , Baço/efeitos dos fármacosRESUMO
Seselin an angular pyranocoumarin at dose of 0.5, 4.5 or 40.5 mg/kg inhibited the writhing response induced by acetic acid in a significant and dose-dependent manner, by 19.5%, 26.2% and 41.4%, respectively. Using the same doses, seselin elicited a significant inhibition of formalin response during the second phase (inflammatory), by 90.3%, 97.8% and 95.3%, respectively. Besides, a significant reduction of licking time was observed during the first phase (neurogenic) at the highest doses of seselin, by 34.4% and 66.9%, respectively. On the contrary, in the hot plate test no effect was observed after seselin treatment. In conclusion, seselin was able to inhibit inflammatory hyperalgesia, suggesting that this natural product possesses both important peripheral anti-inflammatory and antinociceptive properties.