ABSTRACT
The family Boraginaceae is widely distributed in Brazil and in the Northeastern region some species are popularly used to treat symptoms of rheumatism, painful menstruation and dyspepsia. In this work we studied Cordia superba Cham. and C. rufescens A. DC., native from Brazilian Semi-arid region, in order to investigate their immunomodulatory activity. Six extracts were prepared from aerial parts of C. superba and C. rufescens. The cytotoxicity was evaluated using splenocytes from BALB/c mice. The immunomodulatory activity was determined by in vitro assays using activated mouse macrophages and lymphocytes. Peritoneal macrophages obtained from BALB/c mice were stimulated with IFN-gamma and LPS in the presence/absence of the samples. The NO production was measured indirectly through Griess method. Three samples inhibited the production of nitric oxide in values near 50 percent at a concentration of 100 µg/mL. To evaluate the effects of the extracts on lymphocytes, splenocytes from BALB/c mice were incubated with the samples and concanavalin A. Proliferation inhibition was determined by analysis of ³H-thymidine uptake. Samples from the two species had a strong inhibitory activity on lymphocyte proliferation and IL-2 production. Two chloroform extracts prepared from aerial parts of C. rufescens had the lowest IC50 values (7.6 and 11.0 µg/mL).
A família Boraginaceae é amplamente distribuída no Brasil e na região nordeste algumas espécies são usadas popularmente no tratamento de reumatismo, dores menstruais e dispepsias. Neste trabalho foram estudadas as espécies Cordia superba Cham. and C. rufescens A. DC., nativas da região semi-árida brasileira, objetivando investigar a atividade imunomoduladora. Seis extratos foram preparados a partir de partes aéreas das espécies. A citotoxicidade foi avaliada usando culturas de esplenócitos de camundongos BALB/c. A atividade imunomoduladora foi determinada por ensaios in vitro usando macrófagos e linfócitos murinos ativados. Macrófagos peritoneais obtidos de camundongos BALB/c foram estimulados com IFN-gama and LPS na presença/ausência das amostras. A produção de NO foi medida indiretamente através do método de Griess. Três amostras inibiram a produção de NO em valores próximos a 50 por cento (100 µg/mL). Os efeitos das amostras sobre os linfócitos foram avaliados cultivando esplenócitos de camundongos BALB/c em presença destas amostras e de concanavalina A. A proliferação foi determinada pela análise da incorporação de ³H-tritiada. Amostras de duas espécies apresentaram uma forte atividade inibidora sobre a proliferação de linfócitos e sobre a produção de IL-2. Dois extratos clorofórmicos (partes aéreas de C. rufescens) tiveram os menores valores de IC50 (7,6 and 11,0 µg/mL).
Subject(s)
Boraginaceae/immunology , Cordia/immunology , Plant ExtractsABSTRACT
Brugmansia candida (Solanaceae) is a native tree distributed across South-American and produces the pharmacologically- important group of tropane alkaloids including scopolamine. This biocompound is synthesised from hyoscyamine by action of Hyoscyamine 6-â hydroxylase (H6H, EC 1.14.11.11) at the end of the tropane alkaloid pathway. Here are reported the tissue and organ-specific expression of h6hmRNA by RT-PCR analyses and the isolation, cloning and sequencing of the cDNA obtained from B. candida anthers and hairy root transformed cultures. Bioinformatic analysis of the nucleotide sequence revealed an uninterrupted ORF of 1038 bp and the predicted aminoacid sequence could be 344 aminoacid long. A database search showed that this sequence has high homology (97 percent identity) to Hyoscyamus niger H6H protein (Genbank accession number AAA33387.1).
ABSTRACT
The tropane alkaloids scopolamine and hyoscyamine arestill extracted from plants that belong to several species of Solanaceae because their chemical syntesis is difficult and expensive. These anticholinergic agents are employed in medicine as antispasmodics, preoperative medication and for the treatment of motion sickness. In our laboratory, hairy roots of Brugmansia candida, a South American plant which both alkaloids, were obtained through transformation with Agrobacterium rhizogenes and cultured in vitro. To increase the productivity of the cultures, these were exposed to different elicitors: CaCl2, salicylic acid and autoclaved roots of B. candida. The effects on growth, alkaloid accumulation and release into the medium were evaluated. CaCl2 at 50.00 and 100.00 mM, increased the accumulation of scopolamine and hyoscyamine after 24 hours ( 30-60per cent), while after 48 hour levels of 50.00 mM decreased their accumulation ( 50per cent). No effect was observed on release of alkaloids into the medium. Salicylic acid, a compound involved in plant defense, at 0.01 and 1.00 mM increased accumulation of booth alkaloids (ranging from 30 to 170 per cent), particularly after 24 and 48 hours. There was also increase in the release of scopolamine and hyoscyamine into the medium. The homogenized roots had a positive effect on alkaloid accumulation in the roots throughout the experiment (ranging from 100 to 500 per cent). This was most noticeable for hyoscyamine, particulary after 24 and 72 hours of exposition. The results seen with homogenized roots are probably due to endogenous elicitors which are liberated in the subsequent steps of autoclaving and sonication.