Anti-inflammatory effect of Spiranthera odoratissima A. St.-Hil. leaves involves reduction of TNF-alpha

Spiranthera odoratissima A. St.-Hil., 'manaca', is a medicinal species used in Brazil, especially in central region, for the treatment of several diseases such as pain and inflammation. In this study, the methanol/aqueous phase of the ethanol extract of the leaves of 'manaca' (MAP), at the doses of 50, 150 and 500 mg/kg was used to evaluate the anti-inflammatory and/or antinociceptive effects and the possible anti-inflammatory mechanism. The antinociceptive and anti-inflammatory activities of MAP were assessed using formalin test, carrageenan-induced paw oedema. The myeloperoxidase activity, capillary permeability, leukocyte migration and tumour necrosis factor alpha (TNF-alpha) levels were evaluated in pleural exudate. The MAP reduced the licking time only in the later phase of formalin test, and showed anti-inflammatory activity by reducing the paw oedema, migration cell, myeloperoxidase activity, capillary permeability and TNF-alpha levels. In conclusion, we confirmed the inflammatory activity of MAP and affirm that this effect involves the reduction of TNF-alpha level.

Immatures of Lamprosoma amethystinum Perty, 1832 (Chrysomelidae, Lamprosomatinae)

The genus Lamprosoma Kirby, 1818 includes 128 neotropical species and 54 of them are recorded from Brazil (Monros, 1960). The first species with a described larva was L. seraphinum Lacordaire. After that, larvae and pupae of three species were described: L. bicolor Kirby, 1818, L. chorisiae Monros, 1948 and L. azureum Germar, 1824. Fiebrig (1910) described the larva of L. seraphinum Lacordaire, collected on Teminalia hassleriana Chod. (Combretaceae) of Paraguay. Moreira (1913) described L. bicolor collected on Terminalia catappa L., in Rio de Janeiro. According to him, this tree was introduced from Molucas Islands, in Oceania. He also considered it probable that L. bicolor lived on one native species of Terminalia or on another species of Combretaceae and adaptated itself to live on Terminalia catappa. Monros (1949) described L. chorisiae collected on Chorisia speciosa and Ch. insignis [ Ceiba speciosa (A. St.-Hil., A. Juss. & Cambess.) Ravenna and Ceiba insignis (Kunth) P. E. Gibbs & J. Semir] (Bombacaceae) ("" palos borrachos"") in Tucuman. Caxambu and Almeida (1999) described L. azureum collected on Psidium cattleianum Sabine (Myrtaceae)(""araca""), in Parana state. Herein, the larva and pupa of L. amethystinum collected on Terminalia catappa amendoeira-da-praia"", "" chapeu-de-sol"") in Campinas, Sao Paulo state, are described and illustrated.

Essential Oil and other Constituents from Magnolia ovata Fruit

The volatile and non-volatile constituents of the unripe fruits of Magnolia ovata (A. St.-Hil.) Spreng. (Magnoliaceae) were studied. The essential oils were obtained by hydrodistillation of the fruit of two plant populations (A and B) and analyzed by GC/FID and GC/MS. The oil of sample A was rich in sesquiterpenes, mainly spathulenol (19.3%), while the oil of sample B showed a predominance of aliphatic compounds, mainly hexadecanoic acid (52.0%). Extracts of the dried fruit contained fourteen known compounds including nine lignoids (magnovatin A, magnovatin B, acuminatin, licarin A, oleiferin A, oleiferin C, kadsurenin M, 4-O-demethylkadsurenim M and 7-epi-virolin), two sesquiterpene lactones (parthenolide and michelenolide) and three alkaloids (lysicamine, lanuginosine and O-methylmoschatoline). Michelenolide, 7-epi-virolin and lisycamine are reported for the first time in the species, while the remaining compounds have already been reported in the leaves and/or trunk bark of Magnolia ovata. Acetylation of oleiferin A yielded a new compound, acetyl oleiferin A, whose NMR data and that of michelenolide are furnished.

Isolation and characterization of sodium 2-fluoroacetate from Mascagnia rigida using chromatography and infrared spectroscopy

Sodium monofluoroacetate was first identified in Dichapetalum cymosum, a South African plant that can cause livestock poisoning and death. After, several other plants also showed to contain this toxin, which leads to the "sudden death". Mascagnia rigida, a well identified poisonous plant, commonly found in northeast of Brazil also cause sudden death in cattle, which shows clinical signs similar to those produced by the ingestion of plants that contain monofluoroacetate. Our aim was to identify the toxic compound present in the aqueous extract of M. rigida. For this purpose, the dried and milled plant was extracted; the extract was lyophilized and submitted to successive chromatographic process, until the desired purity of the active compound was achieved. The study of this material by planar chromatography and by infrared spectrometry indicated that the toxin can be a mixture of mono, di and trifluoroacetate. (C) 2012 Elsevier Ltd. All rights reserved.

Evaluation of cytotoxic, genotoxic and antigenotoxic potential of Solanum lycocarpum fruits glicoalkaloid extract in V79 cells

Solanum lycocarpum St.-Hil (Solanaceae) is a hairy shrub or small much-branched tree of the Brazilian Cerrado, popularly known as "fruit-of-wolf". Considering that the induction of chromosomal mutations is involved in the process of carcinogenesis, and that S. lycocatpum is often used in folk medicine, it becomes relevant to study its effect on genetic material. In this sense, the aim of present study was to determine the possible cytotoxic, genotoxic and antigenotoxic potentials of S. lycocarpum fruits glycoalkaloid extract (SL) in Chinese hamster lung fibroblasts (V79 cells). The cytotoxicity was evaluated by the colony forming assay, apoptosis and necrosis assay. Trypan blue exclusion dye method and mitotic index. Genotoxic and antigenotoxic potential were evaluated by comet and chromosomal aberrations assays. Four concentrations of SL (4, 8, 16 and 32 mu g/mL) were used for the evaluation of its genotoxic potential. The DNA damage-inducing agent methyl methanesulfonate (MMS, 221 mu g/mL) was utilized in combination with extract to evaluate a possible protective effect. The results showed that SL was cytotoxic at concentrations above 32 mu g/mL by the colony forming assay. For apoptosis and necrosis assay, the concentration of 64 mu g/mL of SL showed statistically significant increase in cell death by apoptosis and necrosis, while the concentrations of 128 and 256 mu g/mL of SL demonstrated statistically significant increase in cell death by necrosis, compared with the control group. Analysis of cell viability by Trypan blue exclusion indicated >96% viability for treatments with concentrations up to 32 mu g/mL of SL No significant differences in MI were observed between cultures treated with different concentrations of 51 (4, 8, 16 and 32 mu g/mL) alone or in combination with MMS and the negative control, indicating that these treatments were not cytotoxic. The comet and chromosomal aberrations assays revealed that SL does not display genotoxic activity. Moreover, the different concentrations of SL showed protective effect against both genomic and chromosomal damages induced by MMS. (C) 2012 Elsevier Ltd. All rights reserved.

Global transcriptional response of Caulobacter crescentus to iron availability

Abstract Background In the alpha subclass of proteobacteria iron homeostasis is controlled by diverse iron responsive regulators. Caulobacter crescentus, an important freshwater α-proteobacterium, uses the ferric uptake repressor (Fur) for such purpose. However, the impact of the iron availability on the C. crescentus transcriptome and an overall perspective of the regulatory networks involved remain unknown. Results In this work we report the identification of iron-responsive and Fur-regulated genes in C. crescentus using microarray-based global transcriptional analyses. We identified 42 genes that were strongly upregulated both by mutation of fur and by iron limitation condition. Among them, there are genes involved in iron uptake (four TonB-dependent receptor gene clusters, and feoAB), riboflavin biosynthesis and genes encoding hypothetical proteins. Most of these genes are associated with predicted Fur binding sites, implicating them as direct targets of Fur-mediated repression. These data were validated by β-galactosidase and EMSA assays for two operons encoding putative transporters. The role of Fur as a positive regulator is also evident, given that 27 genes were downregulated both by mutation of fur and under low-iron condition. As expected, this group includes many genes involved in energy metabolism, mostly iron-using enzymes. Surprisingly, included in this group are also TonB-dependent receptors genes and the genes fixK, fixT and ftrB encoding an oxygen signaling network required for growth during hypoxia. Bioinformatics analyses suggest that positive regulation by Fur is mainly indirect. In addition to the Fur modulon, iron limitation altered expression of 113 more genes, including induction of genes involved in Fe-S cluster assembly, oxidative stress and heat shock response, as well as repression of genes implicated in amino acid metabolism, chemotaxis and motility. Conclusions Using a global transcriptional approach, we determined the C. crescentus iron stimulon. Many but not all of iron responsive genes were directly or indirectly controlled by Fur. The iron limitation stimulon overlaps with other regulatory systems, such as the RpoH and FixK regulons. Altogether, our results showed that adaptation of C. crescentus to iron limitation not only involves increasing the transcription of iron-acquisition systems and decreasing the production of iron-using proteins, but also includes novel genes and regulatory mechanisms.

Global gene expression under nitrogen starvation in Xylella fastidiosa: contribution of the σ54 regulon

Abstract Background Xylella fastidiosa, a Gram-negative fastidious bacterium, grows in the xylem of several plants causing diseases such as citrus variegated chlorosis. As the xylem sap contains low concentrations of amino acids and other compounds, X. fastidiosa needs to cope with nitrogen limitation in its natural habitat. Results In this work, we performed a whole-genome microarray analysis of the X. fastidiosa nitrogen starvation response. A time course experiment (2, 8 and 12 hours) of cultures grown in defined medium under nitrogen starvation revealed many differentially expressed genes, such as those related to transport, nitrogen assimilation, amino acid biosynthesis, transcriptional regulation, and many genes encoding hypothetical proteins. In addition, a decrease in the expression levels of many genes involved in carbon metabolism and energy generation pathways was also observed. Comparison of gene expression profiles between the wild type strain and the rpoN null mutant allowed the identification of genes directly or indirectly induced by nitrogen starvation in a σ54-dependent manner. A more complete picture of the σ54 regulon was achieved by combining the transcriptome data with an in silico search for potential σ54-dependent promoters, using a position weight matrix approach. One of these σ54-predicted binding sites, located upstream of the glnA gene (encoding glutamine synthetase), was validated by primer extension assays, confirming that this gene has a σ54-dependent promoter. Conclusions Together, these results show that nitrogen starvation causes intense changes in the X. fastidiosa transcriptome and some of these differentially expressed genes belong to the σ54 regulon.

Two RND proteins involved in heavy metal efflux in Caulobacter crescentus belong to separate clusters within proteobacteria

Abstract Background Heavy metal Resistance-Nodulation-Division (HME-RND) efflux systems help Gram-negative bacteria to keep the intracellular homeostasis under high metal concentrations. These proteins constitute the cytoplasmic membrane channel of the tripartite RND transport systems. Caulobacter crescentus NA1000 possess two HME-RND proteins, and the aim of this work was to determine their involvement in the response to cadmium, zinc, cobalt and nickel, and to analyze the phylogenetic distribution and characteristic signatures of orthologs of these two proteins. Results Expression assays of the czrCBA operon showed significant induction in the presence of cadmium and zinc, and moderate induction by cobalt and nickel. The nczCBA operon is highly induced in the presence of nickel and cobalt, moderately induced by zinc and not induced by cadmium. Analysis of the resistance phenotype of mutant strains showed that the ΔczrA strain is highly sensitive to cadmium, zinc and cobalt, but resistant to nickel. The ΔnczA strain and the double mutant strain showed reduced growth in the presence of all metals tested. Phylogenetic analysis of the C. crescentus HME-RND proteins showed that CzrA-like proteins, in contrast to those similar to NczA, are almost exclusively found in the Alphaproteobacteria group, and the characteristic protein signatures of each group were highlighted. Conclusions The czrCBA efflux system is involved mainly in response to cadmium and zinc with a secondary role in response to cobalt. The nczCBA efflux system is involved mainly in response to nickel and cobalt, with a secondary role in response to cadmium and zinc. CzrA belongs to the HME2 subfamily, which is almost exclusively found in the Alphaproteobacteria group, as shown by phylogenetic analysis. NczA belongs to the HME1 subfamily which is more widespread among diverse Proteobacteria groups. Each of these subfamilies present distinctive amino acid signatures.