RESUMO
In semi-arid regions, is necessary to explore strategies to mitigate abiotic stresses such as water deficit and salinity. This study aimed to evaluate the stress tolerance capacity of three species subjected to different water regimes and salinity levels, based on dry matter production and water use efficiency (WUE). The species Handroanthus impetiginosus, Vachellia farnesiana, and Amburana cearensis were evaluated in combination with different water regimes (50%, 75%, and 100% of reference evapotranspiration - ET0) and salinity levels (0.18, 1.50, and 1.90 dS m-1). The results show that biomass accumulation increased at 50% and 75% ET0, while the WUE decreased at 100% ET0. The salinity level (1.90 dS m-1) caused reductions in leaf dry biomass (LDB), total dry biomass (TDB), LDB/TDB ratio, and WUE. The negative effects of high salinity on plant height were greater with the application of 75% ET0. The highest WUE was obtained at 50% ET0 for A. cearensis and H. impetiginosus, while V. farnesiana obtained the highest WUE at 75% ET0. A. cearensis exhibited the highest biomass accumulation (2.58 g) and WUE (0.21 g L-1). Overall, the species can tolerate drought and salinity conditions, being sensitive to high salinity concentrations during their initial growth.
The Caatinga is characterized by low water availability and soil salinization. Therefore, assessing the ability of native species to cope with these conditions allows for their utilization in reforestation programs in drought and salinity-exposed environments. Studies on the combined effects of these factors are scarce. The results indicated that native species show tolerance to drought and salinity conditions, albeit with some reductions in biomass production and water use efficiency at high NaCl concentrations. Among the species, A. cearensis performed the best under water and salinity stress conditions.
Assuntos
Fabaceae , Tabebuia , Salinidade , Água , Tolerância ao Sal , Biodegradação Ambiental , Estresse FisiológicoRESUMO
Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii that is highly prevalent worldwide. Although the infection is asymptomatic in immunocompetent individuals, it severely affects immunocompromised individuals, causing conditions such as encephalitis, myocarditis, or pneumonitis. The limited therapeutic efficacy of drugs currently used to treat toxoplasmosis has prompted the search for new therapeutic alternatives. The aim of this study was to determine the anti-Toxoplasma activity of extracts obtained from two species of the genus Tabebuia. Twenty-six extracts, 12 obtained from Tabebuia chrysantha and 14 from Tabebuia rosea, were evaluated by a colorimetric technique using the RH strain of T. gondii that expresses ß-galactosidase. Additionally, the activity of the promising extracts and their active compounds was evaluated by flow cytometry. ß-amyrin was isolated from the chloroform extract obtained from the leaves of T. rosea and displayed important anti-Toxoplasma activity. The results show that natural products are an important source of new molecules with considerable biological and/or pharmacological activity.
Assuntos
Encefalite , Ácido Oleanólico/análogos & derivados , Tabebuia , Toxoplasma , Toxoplasmose , Humanos , Toxoplasmose/tratamento farmacológicoRESUMO
Obesity is characterized by the excessive accumulation of fat, which triggers a low-grade chronic inflammatory process. Currently, the search for compounds with anti-obesogenic effects that help reduce body weight, as well as associated comorbidities, continues. Among this group of compounds are plant extracts and flavonoids with a great diversity of action mechanisms associated with their beneficial effects, such as anti-inflammatory effects and/or as signaling molecules. In the bark of Tabebuia rosea tree, there are different classes of metabolites with anti-inflammatory properties, such as quercetin. Therefore, the present work studied the effect of the ethanolic extract of T. rosea and quercetin on the mRNA of inflammation markers in obesity compared to the drugs currently used. Total RNA was extracted from epididymal adipose tissue of high-fat diet-induced obese Wistar rats treated with orlistat, phentermine, T. rosea extract, and quercetin. The rats treated with T. rosea and quercetin showed 36 and 31% reductions in body weight compared to the obese control, and they likewise inhibited pro-inflammatory molecules: Il6, Il1b, Il18, Lep, Hif1a, and Nfkb1 without modifying the expression of Socs1 and Socs3. Additionally, only T. rosea overexpressed Lipe. Both T. rosea and quercetin led to a reduction in the expression of pro-inflammatory genes, modifying signaling pathways, which led to the regulation of the obesity-inflammation state.
Assuntos
Fármacos Antiobesidade , Tabebuia , Ratos , Animais , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Ratos Wistar , Quercetina/metabolismo , Extratos Vegetais/uso terapêutico , Obesidade/etiologia , Obesidade/induzido quimicamente , Tecido Adiposo/metabolismo , Peso Corporal , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Dieta Hiperlipídica/efeitos adversosRESUMO
The current industrial and human activities scenario has accelerated the widespread use of endocrine-disrupting compounds (EDCs), which can be found in everyday products, including plastic containers, bottles, toys, cosmetics, etc., but can pose a severe risk to human health and the environment. In this regard, fungal bioremediation appears as a green and cost-effective approach to removing pollutants from water resources. Besides, immobilizing fungal cells onto nanofibrous membranes appears as an innovative strategy to improve remediation performance by allowing the adsorption and degradation to occur simultaneously. Herein, we developed a novel nanostructured bioremediation platform based on polyacrylonitrile nanofibrous membrane (PAN NFM) as supporting material for immobilizing an endophytic fungus to remove bisphenol A (BPA), a typical EDC. The endophytic strain was isolated from Handroanthus impetiginosus leaves and identified as Phanerochaete sp. H2 by molecular methods. The successful assembly of fungus onto the PAN NFM surface was confirmed by scanning electron microscopy (SEM). Compared with free fungus cells, the PAN@H2 NFM displayed a high BPA removal efficiency (above 85%) at an initial concentration of 5 ppm, suggesting synergistic removal by simultaneous adsorption and biotransformation. Moreover, the biotransformation pathway was investigated, and the chemical structures of fungal metabolites of BPA were identified by ultra-high performance liquid chromatography - high-resolution mass (UHPLC-HRMS) analysis. In general, our results suggest that by combining the advantages of enzymatic activity and nanofibrous structure, the novel platform has the potential to be applied in the bioremediation of varied EDCs or even other pollutants found in water resources.
Assuntos
Nanofibras , Tabebuia , Poluentes Químicos da Água , Humanos , Nanofibras/química , Fenóis/análise , Fungos , Poluentes Químicos da Água/análiseRESUMO
The role of natural selection in shaping spatial patterns of genetic diversity in the Neotropics is still poorly understood. Here, we perform a genome scan with 24,751 probes targeting 11,026 loci in two Neotropical Bignoniaceae tree species: Handroanthus serratifolius from the seasonally dry tropical forest (SDTF) and Tabebuia aurea from savannas, and compared with the population genomics of H. impetiginosus from SDTF. OutFLANK detected 29 loci in 20 genes with selection signal in H. serratifolius and no loci in T. aurea. Using BayPass, we found evidence of selection in 335 loci in 312 genes in H. serratifolius, 101 loci in 92 genes in T. aurea, and 448 loci in 416 genes in H. impetiginosus. All approaches evidenced several genes affecting plant response to environmental stress and primary metabolic processes. The three species shared no SNPs with selection signal, but we found SNPs affecting the same gene in pair of species. Handroanthus serratifolius showed differences in allele frequencies at SNPs with selection signal among ecosystems, mainly between Caatinga/Cerrado and Atlantic Forest, while H. impetiginosus had one allele fixed across all populations, and T. aurea had similar allele frequency distribution among ecosystems and polymorphism across populations. Taken together, our results indicate that natural selection related to environmental stress shaped the spatial pattern of genetic diversity in the three species. However, the three species have different geographical distribution and niches, which may affect tolerances and adaption, and natural selection may lead to different signatures due to the differences in adaptive landscapes in different niches.
Assuntos
Bignoniaceae , Tabebuia , Bignoniaceae/genética , Ecossistema , Genética Populacional , Metagenômica , Polimorfismo de Nucleotídeo Único , Seleção Genética , Tabebuia/genética , Árvores/genéticaRESUMO
OBJECTIVES: Improving economy and well-being in developing nations like India has expanded life expectancy and changed the attention from transmittable to non transmittable diseases such as Parkinson's disease. Tabebuia impetiginosa has been utilized by cultivators as a general tonic, immunostimulant, adaptogen and also in motor disorders. The present investigation was to explore the antiparkinsonian activity of Tabebuia impetiginosa bark by experimental methods. MATERIALS AND METHODS: Control group-I was served with distilled water. Group-II was considered as pathological control [1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) 2mg/nostrils i.n, Reserpine 40mg/kg s.c, Haloperidol 0.5mg/kg, i.p]. Group-III served with standard drug (Apomorphine 40mg/kg, s.c). Group IV and V received aqueous extract of Tabebuia impetiginosa bark in doses of 300 and 500mg/kg/day respectively. Tremor, hypokinesia, muscular rigidity, catatonia, postural immobility, postural instability and catalepsy were assessed for antiparkinsonian activity. RESULTS: The bark extract served group exhibited the increased levels of dopamine (5700±1.84ng/g) when compared to control groups (4300±3.17ng/g). The extract at both the doses displayed a significant reduction in postural flexion, moderate decrease in tremor, muscular rigidity and postural immobility scores but do not exhibit significant lowering of hypokinesia score in reserpine induced Parkinsonian model. The reduction in catatonia and catalepsy scores is more remarkable in case of high dose of extract (500mg/kg) compared to standard drug in Neuroleptic induced Parkinsonism. CONCLUSION: The findings demonstrate that Tabebuia impetiginosa bark extract has significant anti-cataleptic potentials and the antioxidant effect of the bark may also be a significant contributor to its antiparkinsonian activity.
Assuntos
Antipsicóticos , Catatonia , Tabebuia , Animais , Ratos , Casca de Planta , Dopamina/efeitos adversos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Antioxidantes/farmacologia , Catalepsia/induzido quimicamente , Catalepsia/tratamento farmacológico , Haloperidol/efeitos adversos , Reserpina/efeitos adversos , Hipocinesia , Apomorfina/efeitos adversos , Rigidez Muscular , Tremor , Antiparkinsonianos/efeitos adversos , Adjuvantes Imunológicos/efeitos adversos , Água , EncéfaloRESUMO
BACKGROUND: Water is one of the main limiting factors for plant growth and crop productivity. Plants constantly monitor water availability and can rapidly adjust their metabolism by altering gene expression. This leads to phenotypic plasticity, which aids rapid adaptation to climate changes. Here, we address phenotypic plasticity under drought stress by analyzing differentially expressed genes (DEG) in four phylogenetically related neotropical Bignoniaceae tree species: two from savanna, Handroanthus ochraceus and Tabebuia aurea, and two from seasonally dry tropical forests (SDTF), Handroanthus impetiginosus and Handroanthus serratifolius. To the best of our knowledge, this is the first report of an RNA-Seq study comparing tree species from seasonally dry tropical forest and savanna ecosystems. RESULTS: Using a completely randomized block design with 4 species × 2 treatments (drought and wet) × 3 blocks (24 plants) and an RNA-seq approach, we detected a higher number of DEGs between treatments for the SDTF species H. serratifolius (3153 up-regulated and 2821 down-regulated under drought) and H. impetiginosus (332 and 207), than for the savanna species. H. ochraceus showed the lowest number of DEGs, with only five up and nine down-regulated genes, while T. aurea exhibited 242 up- and 96 down-regulated genes. The number of shared DEGs among species was not related to habitat of origin or phylogenetic relationship, since both T. aurea and H impetiginosus shared a similar number of DEGs with H. serratifolius. All four species shared a low number of enriched gene ontology (GO) terms and, in general, exhibited different mechanisms of response to water deficit. We also found 175 down-regulated and 255 up-regulated transcription factors from several families, indicating the importance of these master regulators in drought response. CONCLUSION: Our findings show that phylogenetically related species may respond differently at gene expression level to drought stress. Savanna species seem to be less responsive to drought at the transcriptional level, likely due to morphological and anatomical adaptations to seasonal drought. The species with the largest geographic range and widest edaphic-climatic niche, H. serratifolius, was the most responsive, exhibiting the highest number of DEG and up- and down-regulated transcription factors (TF).
Assuntos
Adaptação Fisiológica/genética , Bignoniaceae/genética , Desidratação , Florestas , Pradaria , RNA-Seq , Tabebuia/genética , Produtos Biológicos , Mudança Climática , Secas , Ecossistema , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , FilogeniaRESUMO
Atmospheric and climate change will expose tropical forests to conditions they have not experienced in millions of years. To better understand the consequences of this change, we studied photosynthetic acclimation of the neotropical tree species Tabebuia rosea to combined 4°C warming and twice-ambient (800 ppm) CO2 . We measured temperature responses of the maximum rates of ribulose 1,5-bisphosphate carboxylation (VCMax ), photosynthetic electron transport (JMax ), net photosynthesis (PNet ), and stomatal conductance (gs ), and fitted the data using a probabilistic Bayesian approach. To evaluate short-term acclimation plants were then switched between treatment and control conditions and re-measured after 1-2 weeks. Consistent with acclimation, the optimum temperatures (TOpt ) for VCMax , JMax and PNet were 1-5°C higher in treatment than in control plants, while photosynthetic capacity (VCMax , JMax , and PNet at TOpt ) was 8-25% lower. Likewise, moving control plants to treatment conditions moderately increased temperature optima and decreased photosynthetic capacity. Stomatal density and sensitivity to leaf-to-air vapour pressure deficit were not affected by growth conditions, and treatment plants did not exhibit stronger stomatal limitations. Collectively, these results illustrate the strong photosynthetic plasticity of this tropical tree species as even fully developed leaves of saplings transferred to extreme conditions partially acclimated.
Assuntos
Dióxido de Carbono , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Tabebuia/fisiologia , Aclimatação , Teorema de Bayes , Mudança Climática , Escuridão , Transporte de Elétrons , Modelos Biológicos , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Temperatura , Árvores/fisiologia , Clima TropicalRESUMO
The Janzen-Connell hypothesis is a well-known explanation for why tropical forests have large numbers of tree species. A fundamental prediction of the hypothesis is that the probability of adult recruitment is less in regions of high conspecific adult density, a pattern mediated by density-dependent mortality in juvenile life stages. Although there is strong evidence in many tree species that seeds, seedlings, and saplings suffer conspecific density-dependent mortality, no study has shown that adult tree recruitment is negatively density dependent. Density-dependent adult recruitment is necessary for the Janzen-Connell mechanism to regulate tree populations. Here, we report density-dependent adult recruitment in the population of Handroanthus guayacan, a wind-dispersed Neotropical canopy tree species. We use data from high-resolution remote sensing to track individual trees with proven capacity to flower in a lowland moist forest landscape in Panama and analyze these data in a Bayesian framework similar to capture-recapture analysis. We independently quantify probabilities of adult tree recruitment and detection and show that adult recruitment is negatively density dependent. The annualized probability of adult recruitment was 3.03% â year-1 Despite the detection of negative density dependence in adult recruitment, it was insufficient to stabilize the adult population of H. guayacan, which increased significantly in size over the decade of observation.
Assuntos
Tabebuia/crescimento & desenvolvimento , Teorema de Bayes , Ecossistema , Florestas , Panamá , Densidade Demográfica , Dinâmica Populacional , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Clima TropicalRESUMO
In this study, based on our previous study, derivatives of naphtho[2,3-b]furan-4,9-diones were synthesized and their antimicrobial activities were evaluated. The screening of these naphthoquinones revealed that the fluorine-containing NQ008 compound exhibited potent and broad antimicrobial activities against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), Gram-negative bacteria, and fungi. The results of the ratio of the minimum bactericidal concentration (MBC) to the minimum inhibitory concentrations (MICs) and time-kill assays suggest that the mode of action of NQ008 is bactericidal. Additionally, the results of a drug resistance study revealed that NQ008 exhibited potent antibacterial activity and may delay the development of bacteria resistance. Furthermore, NQ008 exhibited preliminary antiviral activity against the swine influenza virus and Feline calicivirus.
Assuntos
Anti-Infecciosos/química , Naftoquinonas/química , Tabebuia/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Naftoquinonas/síntese química , Naftoquinonas/farmacologia , Relação Estrutura-Atividade , Tabebuia/metabolismoRESUMO
Tabebuia rosea (rosy trumpet) is an economically important neotropical tree in Mexico that is highly valued for the quality of its wood, which is used for furniture, crafts, and packing, and for its use as an ornamental and shade tree in parks and gardens. During surveys conducted in the lower Balsas River Basin region in the states of Guerrero and Michoacán, symptoms of floral malformation were detected in T. rosea trees. The main objectives of this study were to describe this new disease, to determine its causal agent, and to identify it using DNA sequence data. A second set of objectives was to analyze the phylogenetic relationship of the causal agent to Fusarium spp. associated with Swietenia macrophylla trees with malformation surveyed in the same region and to compare mycotoxin production and the mating type idiomorphs of fusaria recovered from T. rosea and S. macrophylla. Tabebuia rosea showed malformed inflorescences with multiple tightly curled shoots and shortened internodes. A total of 31 Fusarium isolates recovered from symptomatic T. rosea (n = 20) and S. macrophylla (n = 11) trees were identified by molecular analysis as Fusarium pseudocircinatum. Pathogenicity tests showed that isolates of F. pseudocircinatum recovered from T. rosea induced malformation in inoculated T. rosea seedlings. Eighteen F. pseudocircinatum isolates were tested for their ability to produce mycotoxins and other secondary metabolites. Moniliformin, fusaric acid, bikaverin, beauvericin, aurofusarin. and 8-O-methylbostrycoidin were produced by at least one strain of the 18 isolates tested. A multiplex PCR assay for mating type idiomorph revealed that 22 F. pseudocircinatum isolates were MAT1-1 and that 9 were MAT1-2. Here, we report a new disease of T. rosea in Mexico caused by F. pseudocircinatum.
Assuntos
Fusarium , Doenças das Plantas/microbiologia , Tabebuia , Fusarium/genética , Fusarium/patogenicidade , México , Filogenia , Tabebuia/microbiologiaRESUMO
MAIN CONCLUSION: Bignoniaceae species have conserved chloroplast structure, with hotspots of nucleotide diversity. Several genes are under positive selection, and can be targets for evolutionary studies. Bignoniaceae is one of the most species-rich family of woody plants in Neotropical seasonally dry forests. Here we report the assembly of Handroanthus impetiginosus chloroplast genome and evolutionary comparative analyses of ten Bignoniaceae species representing the genera for which whole-genome chloroplast sequences were available. The chloroplast genome of H. impetiginosus is 159,462 bp in size and has a similar structure compared to the other nine species. The total number of genes was slightly variable amongst the Bignoniaceae, ranging from 124 in H. impetiginosus to 144 in Anemopaegma acutifolium. The inverted repeat (IR) size was variable, ranging from 24,657 bp (Tecomaria capensis) to 40,481 bp (A. acutifolium), due to the contraction and retraction at its boundaries. However, gene boundaries were very similar among the ten species. We found 98 forward and palindromic dispersed repeats, and 85 simple sequence repeats (SSRs). In general, chloroplast sequences were highly conserved, with few nucleotide diversity hotspots in the genes accD, clpP, rpoA, ycf1, ycf2. The phylogenetic analysis based on 77 coding genes was highly consistent with Angiosperm Phylogeny Group (APG) IV. Our results also indicate that most genes are under negative selection or neutral evolution. We found no evidence of branch-site selection, implying that H. impetiginosus is not evolving faster than the other species analyzed, notwithstanding we found site positive selection signal in several genes. These genes can provide targets for evolutionary studies in Bignoniaceae and Lamiales species.
Assuntos
Bignoniaceae , Evolução Molecular , Genoma de Cloroplastos , Tabebuia , Bignoniaceae/classificação , Bignoniaceae/genética , Genoma de Cloroplastos/genética , Repetições de Microssatélites/genética , Filogenia , Tabebuia/classificação , Tabebuia/genéticaRESUMO
The extract of Tabebuia avellanedae has been used as a folk medicine, and the various biological activities of T. avellanedae have been extensively studied. However, few studies have reported which natural products play a role in their biological effects. In this study, we evaluated representative naphthoquinones isolated from T. avellanedae and found that furanonaphthoquinones were the key structures required to exhibit STAT3 phosphorylation inhibitory activities. Our SAR analysis indicated that removal of a hydroxyl group enhanced the STAT3 phosphorylation inhibitory activity. In addition, the combined results of a mobility shift assay, SH2 domain binding assay, and docking simulation by Autodock 4.2.6 suggested that (S)-5-hydroxy-2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione (1) could directly bind to the hinge region of STAT3.
Assuntos
Naftoquinonas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Tabebuia/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Fator de Transcrição STAT3/metabolismo , Relação Estrutura-AtividadeRESUMO
Malaria is one of the life-threatening parasitic diseases that is endemic in tropical areas. The increased prevalence of malaria due to drug resistance leads to a high incidence of mortality. Drug discovery based on natural products and secondary metabolites is considered as alternative approaches for antimalarial therapy. Herbal medicines have advantages over modern medicines, including fewer side effects, cost-effectiveness, and affordability encouraging the herbal-based drug discovery. Several naturally occurring, semisynthetic, and synthetic antimalarial medications are on the market. For example, chloroquine is a synthetic medication for antimalarial therapy derived from quinine. Moreover, artemisinin, and its derivative, artesunate with sesquiterpene lactone backbone, is an antimalarial agent originated from Artemisia annua L. A. annua traditionally has been used to detoxify blood and eliminate fever in China. Although the artemisinin-based combination therapy against malaria has shown exceptional responses, the limited medicinal options demand novel therapeutics. Furthermore, drug resistance is the cause in most cases, and new medications are proposed to overcome the resistance. In addition to conventional therapeutics, this review covers some important genera in this area, including Artemisia, Cinchona, Cryptolepis, and Tabebuia, whose antimalarial activities are finely verified.
Assuntos
Antimaláricos/uso terapêutico , Artemisia/química , Cinchona/química , Cryptolepis/química , Malária/tratamento farmacológico , Plantas Medicinais/química , Tabebuia/química , Antimaláricos/farmacologia , HumanosRESUMO
Tabebuia impetiginosa, a plant native to the Amazon rainforest and other parts of Latin America, is traditionally used for treating fever, malaria, bacterial and fungal infections, and skin diseases. Additionally, several categories of phytochemicals and extracts isolated from T. impetiginosa have been studied via various models and displayed pharmacological activities. This review aims to uncover and summarize the research concerning T. impetiginosa, particularly its traditional uses, phytochemistry, and immunopharmacological activity, as well as to provide guidance for future research. A comprehensive search of the published literature was conducted to locate original publications pertaining to T. impetiginosa up to June 2020. The main inquiry used the following keywords in various combinations in titles and abstracts: T. impetiginosa, Taheebo, traditional uses, phytochemistry, immunopharmacological, anti-inflammatory activity. Immunopharmacological activity described in this paper includes its anti-inflammatory, anti-allergic, anti-autoimmune, and anti-cancer properties. Particularly, T. impetiginosa has a strong effect on anti-inflammatory activity. This paper also describes the target pathway underlying how T. impetiginosa inhibits the inflammatory response. The need for further investigation to identify other pharmacological activities as well as the exact target proteins of T. impetiginosa was also highlighted. T. impetiginosa may provide a new strategy for prevention and treatment of many immunological disorders that foster extensive research to identify potential anti-inflammatory and immunomodulatory compounds and fractions as well as to explore the underlying mechanisms of this herb. Further scientific evidence is required for clinical trials on its immunopharmacological effects and safety.
Assuntos
Compostos Fitoquímicos/química , Tabebuia/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Medicina Tradicional , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Tabebuia/classificação , Tabebuia/metabolismoRESUMO
The rhizosphere of plants contains a diversity of microorganisms, some of which play an important role in the growth and development of the host plant. In this work, the diversity of fungi and bacteria associated to the rhizosphere of Tabebuia chrysantha and T. billbergii plants was analyzed. The molecular identification was performed by sequencing the ITS and 16S rDNA for fungi and bacteria, respectively. The analysis of the rDNA sequences of the rhizosphere of T. billergii showed that for domain Eukaria, the most abundant phyla were Glomeromycota (56%) and Ascomycota (39%), and for domain Bacteria, the phylum Firmicutes (19.17%) was the most abundant followed by Actinobacteria (14.90%) and Proteobacteria (8.94%). In the rhizosphere of T. chrysantha the most abundant phylum of Eukaria was Ascomycota (98%), and for Bacteria the most representative phyla were Proteobacteria (18.61%) and Actinobacteria (11.93%). A diversity of genera and species of fungi and bacteria was observed, to be more significant in T. chrysantha than T. billbergii. The taxonomic assignment of metagenomic sequences revealed a homology associated with genomic sequences of 546 bacteria and 147 fungi in T. chrysantha and 154 bacteria and 122 fungi in T. billbergii.
Assuntos
Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Microbiologia do Solo , Tabebuia/microbiologia , Bactérias/classificação , Bactérias/genética , Biodiversidade , Fungos/classificação , Fungos/genética , Metagenômica , Filogenia , RizosferaRESUMO
Leishmaniasis is one of the most important neglected diseases worldwide. It is a life-threatening disease and causes significant morbidity, long-term disability, and early death. Treatment involves disease control or use of intervention measures, although the currently used drugs require long-lasting therapy, and display toxicity and reduced efficacy. The use of natural products isolated from plants, such as lapachol, an abundant naphthoquinone naturally occurring in South American Handroanthus species (Tabebuia, Bignoniaceae), is a promising option for the treatment of leishmaniasis. In this study, we investigated the leishmanicidal activity of lapachol in vitro and in vivo against Leishmania infantum and L. amazonensis, causative agents of visceral and cutaneous leishmaniasis, respectively. Low cytotoxicity in HepG2 cells (3405.8⯱â¯261.33⯵M), good anti-Leishmania activity, and favorable selectivity indexes (SI) against promastigotes of both L. amazonensis (IC50â¯=â¯79.84⯱â¯9.10⯵M, SIâ¯=â¯42.65) and L. infantum (IC50â¯=â¯135.79⯱â¯33.04⯵M, SIâ¯=â¯25.08) were observed. Furthermore, anti-Leishmania activity assays performed on intracellular amastigotes showed good activity for lapachol (IC50â¯=â¯191.95⯵M for L. amazonensis and 171.26⯵M for L. infantum). Flow cytometric analysis demonstrated that the cytotoxic effect of lapachol in Leishmania promastigotes was caused by apoptosis-like death. Interestingly, the in vitro leishmanicidal effect of lapachol was confirmed in vivo in murine models of visceral and cutaneous leishmaniasis, as lapachol (25â¯mg/kg oral route for 24â¯h over 10 days) was able to significantly reduce the parasitic load in skin lesions, liver, and spleen, similar to amphotericin B, the reference drug. These results reinforce the therapeutic potential of lapachol, which warrants further investigations as an anti-leishmaniasis therapeutic.
Assuntos
Antiprotozoários/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Visceral/tratamento farmacológico , Naftoquinonas/uso terapêutico , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Anfotericina B/toxicidade , Animais , Antiprotozoários/farmacologia , Antiprotozoários/toxicidade , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Células Hep G2/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Fígado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Naftoquinonas/farmacologia , Naftoquinonas/toxicidade , Carga Parasitária , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Células RAW 264.7/efeitos dos fármacos , Células RAW 264.7/parasitologia , Distribuição Aleatória , Pele/parasitologia , Baço/parasitologia , Tabebuia/químicaRESUMO
Medicinal plants are a rich source of natural products used to treat many diseases; therefore, they are the basis for a new drug discovery. Plants are capable of generating different bioactive secondary metabolites, but a large amount of botanical material is often necessary to obtain small amounts of the target substance. Nowadays, many medicinal plants are becoming rather scarce. For this reason, it is important to point out the interactions between endophytic microorganisms and the host plant, because endophytes are able to produce highly diverse compounds, including those from host plants that have important biological activities. Thence, this review aims at presenting the richness in bioactive compounds of the medicinal plants from Tabebuia and Handroanthus genera, as well as important aspects about endophyte-plant interactions, with emphasis on the production of bioactive compounds by endophytic fungi, which has been isolated from various medicinal plants for such a purpose. Furthermore, bio-prospection of natural products synthesized by endophytes isolated from the aforementioned genera used in traditional medicine could be used to treat illnesses.
Assuntos
Produtos Biológicos/metabolismo , Endófitos/metabolismo , Fungos/metabolismo , Plantas Medicinais/metabolismo , Tabebuia/metabolismo , Animais , HumanosRESUMO
Tabebuia avellanedae has been traditionally used as an herbal remedy to alleviate various diseases. However, the plant's pharmacological activity in allergic and inflammatory diseases and its underlying mechanism are not fully understood. Therefore, we investigated the pharmacological activity of Tabetri (T. avellanedae ethanol extract (Ta-EE)) in the pathogenesis of AD. Its underlying mechanism was explored using an AD mouse model and splenocytes isolated from this model. Ta-EE ameliorated the AD symptoms without any toxicity and protected the skin of 2,4-dinitrochlorobenzene- (DNCB-) induced AD mice from damage and epidermal thickness. Ta-EE reduced the secreted levels of allergic and proinflammatory cytokines, including histamine, immunoglobulin E (IgE), interleukin- (IL-) 4, and interferon-gamma (IFN-γ) in the DNCB-induced AD mice. Ta-EE suppressed the mRNA expression of T helper 2-specific cytokines, IL-4 and IL-5, and the proinflammatory cytokine IFN-γ in the atopic dermatitis skin lesions of AD mice. Moreover, Ta-EE suppressed the mRNA expression of IL-4, IL-5, IFN-γ, and another proinflammatory cytokine, IL-12, in the Con A-stimulated splenocytes. It also suppressed IL-12 and IFN-γ in the LPS-stimulated splenocytes. Taken together, these results suggest that Ta-EE protects against the development of AD through the inhibition of mRNA expression of T helper 2-specific cytokines and other proinflammatory cytokines.
Assuntos
Dermatite Atópica/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Tabebuia/química , Animais , Peso Corporal/efeitos dos fármacos , Dermatite Atópica/induzido quimicamente , Dinitroclorobenzeno/toxicidade , Ensaio de Imunoadsorção Enzimática , Etanol/química , Interferon gama/metabolismo , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Masculino , Camundongos , Extratos Vegetais/química , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Knowledge of the environmental distribution of C. neoformans/C. gattii is important in the epidemiology and ecology of the etiological agent, which causes cryptococcosis, a deadly disease worldwide. The aim of this report is to describe the presence of C. neoformans/C. gattii in new environmental niches in Colombia. A total of 837 environmental samples were collected from six different species of trees across four cities; molecular type was determined by PCR fingerprinting and RFLP. Molecular type VNI and VGIII were isolated from different species of trees, resulting in two novel niches for this pathogen: Tabebuia guayacan and Roystonea regia.