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1.
Heredity (Edinb) ; 128(3): 141-153, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35132209

RESUMO

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/genética
2.
Environ Technol ; 43(8): 1129-1139, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32875965

RESUMO

Plant interactions with endophytic bacteria produce mutual benefits and contribute to environmental sustainability. Handroanthus impetiginosus (Mart. ex DC.) Mattos 'pink lapacho' (syn. Tabebuia impetiginosa, Bignoniaceae) is a medicinal, ornamental and forestal native tree from South and Mesoamerica. Plant growth promoting bacteria (PGPB) isolated from pink lapacho are scarcely described. The aim of this work was to isolate and characterize native endophytic bacteria from pink lapacho. Ten bacterial strains were isolated from leaves and six from roots of naturally growing trees in Luján (Central-Eastern region of Argentina). Endophytes were identified as Bacillus, Paenibacillus, Pseudomonas, Rhizobium, Rummeliibacillus and Methylobacterium genera, according to 16S rRNA gene sequencing and phylogenetic analysis. In the present study, a strain of the Rummelibacillus genus (L14) has been first ever reported as endophyte. This strain was capable of growing in Nfb medium and exhibited zinc solubilization ability. A high percentage of strains showed PGPB traits; namely 88% fixed nitrogen, 63% solubilized zinc, 69% solubilized phosphate and 63% produced indole compounds such as IAA. Most strains were salt tolerant that confer them a potential competitive advantage to survive in saline conditions. To the best of our knowledge, this is the first study reporting an approach to assess the diversity of cultivable endophytic bacteria of H. impetiginosus tree and its plant growth promoting capacity. The knowledge about this kind of associations could contribute to environmental sustainability by developing effective biofertilizers that minimize the use of chemical fertilizers and pesticides.


Assuntos
Tabebuia , Bactérias , Endófitos/genética , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/efeitos da radiação , Tabebuia/efeitos dos fármacos , Tabebuia/fisiologia
3.
BMC Plant Biol ; 21(1): 463, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641780

RESUMO

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 , Filogenia
4.
Chem Pharm Bull (Tokyo) ; 69(7): 661-673, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34193715

RESUMO

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/metabolismo
5.
Plant Dis ; 105(10): 2822-2829, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33904328

RESUMO

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/microbiologia
6.
Sci Rep ; 11(1): 8405, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33863934

RESUMO

Tabebuia is the largest genus among the family Bignoniaceae. Tabebuia species are known for their high ornamental and curative value. Here, the cytotoxic potential of extracts from the leaves and stems of five Tabebuia species was analyzed. The highest activity was observed for T. rosea (Bertol.) DC. stem extract against HepG2 cell line (IC50 4.7 µg/mL), T. pallida L. stem extract against MCF-7 cell line (IC50 6.3 µg/mL), and T. pulcherrima stem extract against CACO2 cell line (IC50 2.6 µg/mL). Metabolic profiling of the ten extracts using liquid chromatography-high-resolution mass spectrometry for dereplication purposes led to annotation of forty compounds belonging to different chemical classes. Among the annotated compounds, irridoids represent the major class. Principle component analysis (PCA) was applied to test the similarity and variability among the tested species and the score plot showed similar chemical profiling between the leaves and stems of both T. pulcherrima and T. pallida L. and unique chemical profiling among T. rosea (Bertol.) DC., T. argentea Britton, and T. guayacan (Seem.) Hemsl. leaf extracts and the stem extract of T. rosea (Bertol.) DC. Additionally, a molecular correlation analysis was used to annotate the bioactive cytotoxic metabolites in the extracts and correlate between their chemical and biological profiles.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Metaboloma/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Tabebuia/química , Células CACO-2 , Células Hep G2 , Humanos , Células MCF-7 , Neoplasias/metabolismo , Neoplasias/patologia
7.
G3 (Bethesda) ; 11(2)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33693604

RESUMO

The lack of genomic resources for tropical canopy trees is impeding several research avenues in tropical forest biology. We present genome assemblies for two Neotropical hardwood species, Jacaranda copaia and Handroanthus (formerly Tabebuia) guayacan, that are model systems for research on tropical tree demography and flowering phenology. For each species, we combined Illumina short-read data with in vitro proximity-ligation (Chicago) libraries to generate an assembly. For Jacaranda copaia, we obtained 104X physical coverage and produced an assembly with N50/N90 scaffold lengths of 1.020/0.277 Mbp. For H. guayacan, we obtained 129X coverage and produced an assembly with N50/N90 scaffold lengths of 0.795/0.165 Mbp. J. copaia and H. guayacan assemblies contained 95.8% and 87.9% of benchmarking orthologs, although they constituted only 77.1% and 66.7% of the estimated genome sizes of 799 and 512 Mbp, respectively. These differences were potentially due to high repetitive sequence content (>59.31% and 45.59%) and high heterozygosity (0.5% and 0.8%) in each species. Finally, we compared each new assembly to a previously sequenced genome for Handroanthus impetiginosus using whole-genome alignment. This analysis indicated extensive gene duplication in H. impetiginosus since its divergence from H. guayacan.


Assuntos
Bignoniaceae , Tabebuia , Bignoniaceae/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Tabebuia/genética , Árvores/genética
8.
Plant Cell Environ ; 44(7): 2347-2364, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33759203

RESUMO

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 Tropical
9.
Sci Rep ; 11(1): 5519, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750911

RESUMO

Bark from the Handroanthus impetiginosus (Mart. ex DC.) Mattos (Bignoniaceae) tree has long been used in traditional South American healing practises to treat inflammation. However, its anti-inflammatory activity has not been closely examined. Here we use chemical extraction, qualitative phytochemical examination, toxicity testing and quantitative examination of anti-inflammatory activity on human cells ex vivo. All extracts were found to be nontoxic. We found different extracts exhibited unique cytokine profiles with some extracts outperforming a positive control used in the clinic. These results verify the immunomodulatory activity of Handroanthus impetiginosus (Mart. ex DC.) Mattos (Bignoniaceae) tree bark-derived compounds. Collectively, combining a lack of toxicity and potency in human immune cells supports further fractionation and research.


Assuntos
Citocinas/imunologia , Fatores Imunológicos , Linfócitos/imunologia , Casca de Planta/química , Extratos Vegetais , Plantas Medicinais/química , Tabebuia/química , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
10.
Arch Physiol Biochem ; 127(1): 61-72, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31094218

RESUMO

Hyperuricaemia is characterised by a high level of urate in the blood. The crystallisation of urate is considered a critical risk factor for the development of gout. Allopurinol and febuxostat have been commonly used medications to decrease the circulating urate levels. However, the use of these drugs is associated with undesired side effects. Therefore, the development of a new active, safety anti-hyperuricaemic and anti-inflammatory drug could be useful in gout therapy and is highly justified. Natural products have become a source of new pharmaceuticals due to their strong efficacy with less side effects, which relies on the comprising of complex bioactive compounds. There are a growing number of studies purporting decreasing serum urate with traditional medicines. This article was aimed to review these studies and identify which extracts promote urate reduction, along with their different mechanisms.


Assuntos
Anti-Inflamatórios/farmacologia , Produtos Biológicos/farmacologia , Gota/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Animais , Artrite Gotosa/tratamento farmacológico , Asteraceae/efeitos dos fármacos , Método Duplo-Cego , Humanos , Inflamação/tratamento farmacológico , Camundongos , Placebos , Extratos Vegetais/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Tabebuia/efeitos dos fármacos , Ácido Úrico/química , Xantina Oxidase/metabolismo
11.
Nat Prod Res ; 35(22): 4632-4637, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31797686

RESUMO

Both ethyl acetate and aqueous fractions of Tabebuia aurea leaves exhibited noteworthy antioxidant and nephroprotective activities against carbon tetrachloride (CCl4)-induced nephrotoxicity in rats, as evidenced by the remarkable improvements of renal serum biomarkers and histopathological features. Additionally, the ethyl acetate fraction displayed a prominent in vitro antitrypanosomal activity against Trypanosoma brucei; consequently, the leaves were subjected to LC-HR-ESI-MS metabolomic profiling to discover the constituents that possibly underlie their bioactivities. Therefore, ten metabolites were characterized, mostly dominated by flavonoids. Interestingly, two identified constituents viz., 3,9,12,15-octadecatetraenoic acid (9) and 9,11,13-octadecatrienoic acid (10) are reported firstly herein from the genus Tabebuia. Furthermore, among the dereplicated constituents, rutin (5) and kaempferol 3-O-rutinoside (6) exhibited the highest docking scores as effective antitrypanosomal compounds.


Assuntos
Bignoniaceae , Tabebuia , Animais , Antioxidantes , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos
12.
Eur J Med Chem ; 210: 112962, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33158575

RESUMO

ß-Lapachone (ß-lap, 1), an ortho-naphthoquinone natural product isolated from the lapacho tree (Tabebuia avellanedae) in many regions of South America, has received extensive attention due to various pharmacological activities, such as antitumor, anti-Trypanosoma cruzi, anti-Mycobacterium tuberculosis, antibacterial, and antimalarial activities. Related mechanisms of ß-lap have been widely investigated for a full understanding of its therapeutic potentials. Numerous derivatives of ß-lap have been reported with aims to generate new chemical entities, improve the corresponding biological potency, and overcome disadvantages of its physical and chemical properties and safety profiles. This review will give insight into the pharmacological mechanisms of ß-lap and provide a comprehensive understanding of its structural modifications with regard to different therapeutic potentials. The available clinical trials related to ß-lap and its derivatives are also summarized.


Assuntos
Naftoquinonas/química , Naftoquinonas/farmacologia , Tabebuia/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Descoberta de Drogas , Humanos , Naftoquinonas/uso terapêutico , Neoplasias/tratamento farmacológico
13.
F1000Res ; 9: 1262, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33214880

RESUMO

Background: A large number of chemical compounds exert their antioxidant effects by activation of key transcriptional regulatory mechanisms, such as the transcription factor Nrf2. The aim of this study was to evaluate the activation of the Keap1-Nrf2 pathway by both the n-butanol extract obtained from the inner bark of Tabebuia rosea (Bertol) DC and specioside isolated from this extract. Methods: The antioxidant activity of the extract and specioside isolated from the inner bark of T. rosea were evaluated using the oxygen radical absorbance capacity (ORAC) and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH) techniques, whereas their effects on the viability of HepG2 cells was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The effects of the compound and the extract on activating the Keap1-Nrf2 pathway were evaluated using a Nrf2 Transcription Factor Assay kit. Induction of the Nrf2-mediated antioxidant response genes HMOX-1 and NQO1 was evaluated by real-time PCR. The protective effects against H 2O 2-induced oxidative stress in HepG2 cells was determined as the percent protection using the MTT method. Results: Both the n-butanol extract and specioside exhibited activity at low concentrations without affecting cellular viability, since the cell viability was greater than 80% after 24 hours of exposure at each tested concentration. In addition, Nrf2 dissociated from Keap1 after treatment with the n-butanol extract at a concentration of 0.25 µg/mL after 4 hours of exposure. An increase in the Nrf2 level in the cytoplasm after 4 hours of exposure to 2 µM specioside was observed. Nrf2 levels stabilized in the nucleus 12 hours after stimulation with both specioside and the extract. After 6 hours of stimulation, both the extract and specioside induced the expression of HMOX-1 and NQO1. Conclusion: The n-butanol extract from the inner bark of T. rosea and specioside produced protective effects against H 2O 2-induced oxidative stress in HepG2 cells.


Assuntos
Fator 2 Relacionado a NF-E2 , Tabebuia , 1-Butanol , Glucosídeos Iridoides , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Casca de Planta , Extratos Vegetais/farmacologia
14.
Planta ; 252(5): 91, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33098500

RESUMO

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/genética
15.
Int J Biol Macromol ; 165(Pt A): 849-856, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33010272

RESUMO

Barks of trees of the genus Handroanthus are known for their antitumor activity, which is attributed to naphthoquinones. Another class of molecules that has shown antitumor activity are the polysaccharides, however those from Handroanthus barks have never been studied. Accordingly, the aim of this study was to extract polysaccharides from H. heptaphyllus and H. albus barks, to characterize them structurally and to evaluate their cytotoxic effects on the human colon and human breast cancer cell lines, Caco-2 and MCF-7, respectively. The polysaccharides were extracted with boiling water and fractionated by freeze-thawing process. The soluble polysaccharide fractions HHBSF and HABSF were characterized by monosaccharide composition, methylation and NMR analyses, and their effects on proliferation of Caco-2 and MCF-7 cells were evaluated using MTT cell viability assay. HHBSF and HABSF were mainly constituted of galactoglucomannan, type II arabinogalactan (AGII) and type I rhamnogalacturonan (RGI), however, only HABSF significantly inhibited the growth of MCF-7 (CC50 = 327 µg/mL) and Caco-2 (CC50 = 2258 µg/mL) cells. Differences in the fine structure and proportion of their polysaccharides, and maybe in the composition of associated phenolic compounds could explain the different effects of HHBSF and HABSF.


Assuntos
Citotoxinas , Casca de Planta/química , Polissacarídeos , Tabebuia/química , Animais , Células CACO-2 , Chlorocebus aethiops , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Humanos , Células MCF-7 , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Células Vero
16.
Molecules ; 25(18)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962180

RESUMO

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/metabolismo
17.
Int Immunopharmacol ; 87: 106810, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32707497

RESUMO

Inflammation plays a significant role in the pathogenesis of chronic diseases. Inflammatory diseases such as bacterial diseases, Alzheimer's disease, rheumatoid arthritis, multiple sclerosis, and so on, impose huge costs on the health systems. On the other hand, some side effects have been reported for the classic drugs used to treat these diseases. Plants phytochemicals have revealed important prospects in the handling and controlling of human diseases. ß-lapachone, is a derivative of the naturally occurring element lapachol, from Tabebuia avellanedae and its anti-inflammatory effects have been reported in several reports. This review summarized the evidence from cell and animal studies supporting the anti-inflammatory role of ß-lapachone and discussed its potential mechanisms.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Infecções Bacterianas/tratamento farmacológico , Inflamação/terapia , Esclerose Múltipla/tratamento farmacológico , Naftoquinonas/uso terapêutico , Animais , Humanos , Tabebuia/imunologia
18.
PLoS One ; 15(4): e0231083, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32255799

RESUMO

Plant-associated microbial communities have diverse phenotypic effects on their hosts that are only beginning to be revealed. We hypothesized that morpho-physiological variations in the tropical tree Tabebuia heterophylla, observed on different geological substrates, arise in part due to microbial processes in the rhizosphere. We characterized the microbiota of the rhizosphere and soil communities associated with T. heterophylla trees in high and low altitude sites (with varying temperature and precipitation) of volcanic, karst and serpentine geologies across Puerto Rico. We sampled 6 areas across the island in three geological materials including volcanic, serpentine and karst soils. Collection was done in 2 elevations (>450m and 0-300m high), that included 3 trees for each site and 4 replicate soil samples per tree of both bulk and rhizosphere. Genomic DNA was extracted from 144 samples, and 16S rRNA V4 sequencing was performed on the Illumina MiSeq platform. Proteobacteria, Actinobacteria, and Verrucomicrobia were the most dominant phyla, and microbiomes clustered by geological substrate and elevation. Volcanic samples were enriched in Verrucomicrobia; karst was dominated by nitrogen-fixing Proteobacteria, and serpentine sites harbored the most diverse communities, with dominant Cyanobacteria. Sites with similar climates but differing geologies showed significant differences on rhizobiota diversity and composition demonstrating the importance of geology in shaping the rhizosphere microbiota, with implications for the plant's phenotype. Our study sheds light on the combined role of geology and climate in the rhizosphere microbial consortia, likely contributing to the phenotypic plasticity of the trees.


Assuntos
Raízes de Plantas/microbiologia , Rizosfera , Microbiologia do Solo , Tabebuia/genética , Actinobacteria/classificação , Actinobacteria/genética , Geologia , Filogenia , Raízes de Plantas/genética , Proteobactérias/classificação , Proteobactérias/genética , Porto Rico , RNA Ribossômico 16S/genética , Tabebuia/crescimento & desenvolvimento , Tabebuia/microbiologia , Clima Tropical
19.
J Pharm Pharmacol ; 72(7): 990-999, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32311118

RESUMO

OBJECTIVES: This research aimed to evaluate the antiangiogenic activity of isolated flavonoid 4a,5,8,8a-tetrahydro-5-hydroxy-3,7,8-trimethoxy-2-(3,4-dimethoxyphenyl) chromen-4-one (TMF) from Tabebuia chrysantha. STAT3-MMP9 signalling is a signal transduction mechanism that promotes angiogenesis in various cancers. METHODS: The tumour xenografting chicken embryo chorioallantoic membrane (CAM) model-based ex vivo assay was used to evaluate the activity of TMF. The Western blot, densitometric analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to evaluate the activity of the MMP9. Zebrafish embryos were used to evaluate embryotoxicity, and in vitro free radical scavenging activity of flavonoid was also elucidated. KEY FINDINGS: This research assessed the high level of STAT3, p-ERK, VEGF-R and MMP9 in the tissue extract of the control group, and also, the suppression of angiogenesis in the treatment groups was due to scavenged ROS and RNS, dephosphorylation of STAT3 and ERK, and suppression of MMP9 gene expression. CONCLUSION: The isolated flavonoid named TMF from T. chrysantha functions as specific regulators of target proteins of angiosarcoma. The STAT3-MMP9 signalling may be used as an effective prognostic marker of angiosarcoma.


Assuntos
Inibidores da Angiogênese/farmacologia , Hemangiossarcoma/tratamento farmacológico , Metaloproteinase 9 da Matriz/metabolismo , Fator de Transcrição STAT3/metabolismo , Tabebuia , Animais , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Phytother Res ; 34(7): 1556-1569, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32022345

RESUMO

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 , Humanos
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