Metabolic profiling of cytotoxic metabolites from five Tabebuia species supported by molecular correlation analysis.

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.

The medicinal plant Tabebuia impetiginosa potently reduces pro-inflammatory cytokine responses in primary human lymphocytes.

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.

A comprehensive review on ß-lapachone: Mechanisms, structural modifications, and therapeutic potentials.

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.

Tabebuia impetiginosa: A Comprehensive Review on Traditional Uses, Phytochemistry, and Immunopharmacological Properties.

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.

Medicinal plants used in the treatment of Malaria: A key emphasis to Artemisia, Cinchona, Cryptolepis, and Tabebuia genera.

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.

STAT3 inhibitory activity of naphthoquinones isolated from Tabebuia avellanedae.

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.

ß -Lapachone Regulates Obesity through Modulating Thermogenesis in Brown Adipose Tissue and Adipocytes: Role of AMPK Signaling Pathway.

Activation of brown adipose tissue (BAT) has been proposed as a promising target against obesity due to its increased capacity for thermogenesis. In this study, we explored the effect of ß -Lapachone ( ß L), a compound obtained from the bark of the lapacho tree, against obesity. In vivo administration of ß L into either high fat diet (HFD)-induced obese C57BL6 mice and genetically obese Lepr -∕- mice prevented body weight gain, which was associated with tissue weight loss of white adipose tissue (WAT). In addition, ß L elevated thermogenic proteins including uncoupling protein 1 (UCP1) and mitochondrial count in BAT and human adipose tissue-derived mesenchymal stem cells (hAMSCs). ß L also induced AMP-activated protein kinase (AMPK) phosphorylation, subsequent upregulation of acetyl-CoA carboxylase (ACC) and UCP1, and these effects were diminished by AMPK inhibitor compound C, suggesting that AMPK underlies the effects of ß L. Mitogen-activated protein kinase pathways participated in the thermogenesis of ß L, specifically p38, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase 1/2 (ERK1/2) were activated by ß L treatment in hAMSCs. Additionally, inhibitors of p38/JNK/ERK1/2 abrogated the activity of ß L. Taken together, ß L exerts anti-obese effects by inducing thermogenesis mediated by AMPK signaling pathway, suggesting that ß L may have a potential therapeutic implication of obesity. Taken together, ß L exerts anti-obese effects by not only inducing thermogenesis on brown adipocytes but also inducing the browning of white adipocytes. The anti-obese effect of ß L is mediated by AMPK signaling pathway, suggesting that ß L may have potential therapeutic implication of obesity.

Stem extract of Tabebuia chrysantha induces apoptosis by targeting sEGFR in Ehrlich Ascites Carcinoma.

ETHNOPHARMACOLOGICAL RELEVANCE: The plant Tabebuia chrysantha (Jaq.) Nicholson (Bignoniaceae) is commonly known as "Golden Goddess" in the Southern part of India and "Golden Trumpet Tree " in Central America. Stems of this plant have been traditionally used for antioxidant, anti-inflammatory, antimicrobial and anticancer actions. AIM OF THE STUDY: To evaluate the antitumor activity of methanol extract of Tabebuia chrysantha stem (METC). MATERIALS AND METHODS: The in vivo antitumor potential of METC against Ehrlich Ascites Carcinoma (EAC) in Swiss albino mice was assessed by evaluating tumor volume, viable and nonviable tumor cell count, tumor weight, hematological parameters, biochemical parameters, and antioxidant parameters. The in vitro antitumor potential of METC at different concentrations (100, 200, 400, 800, 1000) µg/mL has been evaluated, by using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and Trypan blue dilution assay for a period of 3 h treatment. Before that, the crude extract was pre-screened for cytotoxicity property using Brine shrimp lethality bioassay. RESULTS: Phytoconstituents 2-Hydroxynaphthalene-1,4-dione, ß-lapachone and 2-((dimethylamino)methyl)-3-methoxynaphthalene-1,4-dione were isolated from the METC. Their occurrence and structures were determined by HPLC chromatography, UV spectroscopy, and 1D and 2D NMR spectroscopies respectively. The extract showed a direct cytotoxic effect on EAC cells in a dose-dependent manner with IG50 value 463.27 µg/mL in MTT assay and 443.58 µg/mL in trypan blue dilution assay. The METC (300 mg/kg) and 5-FU (30 mg/kg) exhibited significant (p < 0.001) decrease in tumor volume, tumor weight and viable cell count of EAC-treated mice. Also, hematological profile, tissue parameters such as lipid peroxidation, reduced glutathione, superoxide dismutase, and catalase were reverted to the normal levels compared to the EAC control group. The Western blotting analysis demonstrated apoptosis of carcinoma was due to inhibition of soluble epidermal growth factor receptor proteins (sEGFR) expression in the blood. CONCLUSION: The antitumor potential of the stem extract of T chrysantha was due to naphthaquinones and polyphenol content in the crude extract and so T chrysantha could be a cytotoxic plant to control tumor growth.

Efficacy of lapachol on treatment of cutaneous and visceral leishmaniasis.

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 µM), good anti-Leishmania activity, and favorable selectivity indexes (SI) against promastigotes of both L. amazonensis (IC50 = 79.84 ±â€¯9.10 µM, SI = 42.65) and L. infantum (IC50 = 135.79 ±â€¯33.04 µM, SI = 25.08) were observed. Furthermore, anti-Leishmania activity assays performed on intracellular amastigotes showed good activity for lapachol (IC50 = 191.95 µM for L. amazonensis and 171.26 µM 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 (25 mg/kg oral route for 24 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.

Tabetri™ (Tabebuia avellanedae Ethanol Extract) Ameliorates Atopic Dermatitis Symptoms in Mice.

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.

Reduction of doxorubicin-induced genotoxicity by Handroanthus impetiginosus in mouse bone marrow revealed by micronucleus assay / Redução da genotoxicidade induzida pela doxorrubicina por Handroanthus impetiginosus na medula óssea de camundongos revelada pelo ensaio do micronúcleo

Abstract Handroanthus impetiginosus has long been used in traditional medicine and various studies have determined the presence of bioactive chemical compounds and potential phytotherapeutics. In this study, the genotoxicity of the lyophilized tincture of H. impetiginosus bark (THI) was evaluated in mouse bone marrow using micronucleus assays. The interaction between THI and genotoxic effects induced by the chemotherapeutic agent, doxorubicin (DXR), was also analyzed. Experimental groups were evaluated 24 to 48 h after treatment with N-nitroso-N-ethylurea (NEU; 50 mg/kg), DXR (5 mg/kg), sodium chloride (NaCl; 150 mM), and THI (0.5-2 g/kg). Antigenotoxic assays were carried out using THI (0.5 g/kg) in combination with NEU or DXR. Analysis of the micronucleated polychromatic erythrocytes (MNPCEs) indicated no significant differences between treatment doses of THI (0.5-2 g/kg) and NaCl. Polychromatic erythrocyte (PCE) to normochromatic erythrocyte (NCE) ratios did not indicate any statistical differences between DXR and THI or NaCl, but there were differences between THI and NaCl. A significant reduction in MNPCEs and PCE/NCE ratios was observed when THI was administered in combination with DXR. This study suggested the absence of THI genotoxicity that was dose-, time-, and gender-independent and the presence of moderate systemic toxicity that was dose-independent, but time- and gender-dependent. The combination of THI and DXR also suggested antigenotoxic effects, indicating that THI reduced genotoxic effects induced by chemotherapeutic agents.

Resumo Handroanthus impetiginosus tem sido usada durante um longo período pela medicina tradicional e vários estudos têm demonstrados a presença de compostos químicos e potencial fitoterapêutico. Esta pesquisa avaliou a genotoxicidade da tintura da casca liofilizada de H. impetiginosus (THI) usando o ensaio do micronúcleo em medula óssea de camundongos. A interação entre THI e os efeitos genotóxicos induzidos pelo quimioterápico doxorrubicina (DXR) também foram analisados. Grupos experimentais foram analisados a 24-48 h após o tratamento com N-Nitroso-N-etiluréia (NEU; 50 mg/kg), DXR (5 mg/kg), NaCl (150 mM) e THI (0,5-2 g/kg). O ensaio antigenotóxico foi conduzido utilizando THI (0,5 g/kg) em combinação com NEU ou DXR. A análise de eritrócitos policromáticos micronucleados (EPCMNs) não mostrou diferenças significativas entre as doses de tratamento (0,5-2 g/kg) e NaCl. As proporções de eritrócitos policromáticos (EPC)/eritrócitos normocromáticos (ENC) não revelaram diferenças estatísticas entre DXR e THI ou NaCl, porém houve diferenças entre THI e NaCl. Uma redução significativa em EPCMNs e na razão EPC/ENC foi observada quando THI foi administrado em combinação com DXR. Essa pesquisa sugere ausência de genotoxicidade de THI, dose-, tempo- e sexo-independente, e moderada toxicidade sistêmica dose-independente, mas tempo- e sexo-dependente. A associação do THI e DXR também sugere efeitos antigenotóxicos. Por conseguinte, THI pode reduzir os efeitos genotóxicos induzidos pelo quimioterapêutico.

Development and Validation of an Analytical Method Readily Applicable for Quality Control of Tabebuia impetiginosa (Taheebo) Ethanolic Extract.

The dried inner bark of Tabebuia impetiginosa, known as taheebo or red lapacho, has numerous beneficial effects on human health. This study presents the first simple and reliable quantitative method that could serve for the QC of taheebo. The method uses LC-UV spectroscopy to determine the veratric acid (VA; 3,4-dimethoxybenzoic acid) content of taheebo extracts (TEs). Sample preparation entailed the dissolution of TE in methanol (MeOH), facilitated by ultrasonic radiation for 10 min. The optimized conditions included chromatographic separation on an Agilent Eclipse Plus C18 column (4.6 × 150 mm, 5 µm) at 30°C. The mobile phase consisted of 1% acetic acid in water and MeOH, which was eluted under gradient mode at a flow rate of 1.0 mL/min. The detection wavelength was 254 nm. Using these conditions, VA was selectively resolved, and the entire chromatographic analysis time was 27 min. The method was linear in the range of 50-500 µg/mL (r2 = 0.9995), precise (≤3.97% RSD), and accurate (97.10-102.72%). The validated method was applied to three batches of TE samples, yielding an estimated VA content range of 14.92-15.58 mg/g. Thus, the proposed method could serve as an easy and practical method for the QC of TEs or related products containing TEs.

Reduction of doxorubicin-induced genotoxicity by Handroanthus impetiginosus in mouse bone marrow revealed by micronucleus assay.

Handroanthus impetiginosus has long been used in traditional medicine and various studies have determined the presence of bioactive chemical compounds and potential phytotherapeutics. In this study, the genotoxicity of the lyophilized tincture of H. impetiginosus bark (THI) was evaluated in mouse bone marrow using micronucleus assays. The interaction between THI and genotoxic effects induced by the chemotherapeutic agent, doxorubicin (DXR), was also analyzed. Experimental groups were evaluated 24 to 48 h after treatment with N-nitroso-N-ethylurea (NEU; 50 mg/kg), DXR (5 mg/kg), sodium chloride (NaCl; 150 mM), and THI (0.5-2 g/kg). Antigenotoxic assays were carried out using THI (0.5 g/kg) in combination with NEU or DXR. Analysis of the micronucleated polychromatic erythrocytes (MNPCEs) indicated no significant differences between treatment doses of THI (0.5-2 g/kg) and NaCl. Polychromatic erythrocyte (PCE) to normochromatic erythrocyte (NCE) ratios did not indicate any statistical differences between DXR and THI or NaCl, but there were differences between THI and NaCl. A significant reduction in MNPCEs and PCE/NCE ratios was observed when THI was administered in combination with DXR. This study suggested the absence of THI genotoxicity that was dose-, time-, and gender-independent and the presence of moderate systemic toxicity that was dose-independent, but time- and gender-dependent. The combination of THI and DXR also suggested antigenotoxic effects, indicating that THI reduced genotoxic effects induced by chemotherapeutic agents.

Evaluation of antipyretic, sedative and hypnotic activities of methanol extract of Tabebuia hypoleuca (C. Wright ex Sauvalle) Urb. stems / [Evaluación de la actividad antipirética, sedante e hipnótica del extracto metanólico de los tallos de Tabebuia hypoleuca (C. Wright ex Sauvalle) Urb

Species of the genus Tabebuia are used in traditional medicine and are reported in the literature for their properties against various diseases. The objective of this study was to evaluate the antipyretic, sedative and hypnotic activities of methanol extract of Tabebuia hypoleuca stems (THME) using the Brewer's yeast induced pyrexia, Open field and Sodium thiopental-induced sleeping time tests, respectively. In the Brewer's yeast induced pyrexia test, THME at 500 mg/kg produced a significant (p<0.001) decrease of the fever as from the first hour after administration and was sustained for 4 h. In the Open-field test, THME did not cause any significant change in the number of crossings, rearing, preening and defecation, and either in the time of immobility. Moreover, THME did not produce changes in neither the sleeping latency nor the sleeping time induced by sodium thiopental. These results showed that THME administered orally at 500 mg/kg exerts antipyretic activity, probably mediated by the inhibition of the enzyme cyclooxygenase-2. This study also showed that THME does not exert sedative and hypnotic effects at the doses tested.

Especies del género Tabebuia se utilizan en la medicina tradicional y se reportan en la literatura por sus propiedades contra diversas enfermedades. El objetivo de este estudio fue evaluar la actividad antipirética, sedante e hipnótica del extracto metanólico de los tallos de Tabebuia hypoleuca (THME) utilizando las pruebas de pirexia inducida por levadura de cerveza, campo abierto y tiempo de sueño inducido por tiopental sódico respectivamente. En el ensayo de pirexia inducida por levadura de cerveza, THME a 500 mg/kg produjo una reducción significativa (p<0.001) de la fiebre a partir de la primera hora después de la administración y se mantuvo durante cuatro horas. En el ensayo de campo abierto, THME no causó ningún cambio significativo en el número de cruces, levantamientos, acicalamientos y defecación, ni en el tiempo de inmovilidad. Además, THME no produjo cambios ni en la latencia de sueño, ni en el tiempo de sueño inducido por tiopental sódico. Estos resultados mostraron que THME administrado oralmente en dosis de 500 mg/kg posee actividad antipirética, mediado probablemente a la inhibición de la enzima ciclooxigenasa-2. Este estudio también demostró que THME no posee actividad sedante e hipnótica en las dosis ensayadas.

Iridoid Esters from Tabebuia avellanedae and Their In Vitro Anti-inflammatory Activities.

A phytochemical investigation of the inner bark of Tabebuia avellanedae Lorentz ex Griseb was carried out by various chromatographic techniques, resulting in the isolation and characterization of eight new iridoid esters, namely Avelladoids A-H (1-8). Their chemical structures were elucidated on the basis of extensive spectroscopic analyses, especially 2D NMR experiments and HRMS data. The anti-inflammatory effects of 1-8 were determined on an LPS-stimulated RAW 264.7 cell line. Among them, compounds 1, 2, and 3 exhibited anti-inflammatory activities by inhibition of NO and PGE2 production in a dose-dependent manner, without altering cell viability.

Análise fitoquímica e das atividades citotóxica, antioxidante, e antibacteriana das flores de Tabebuia serratifolia (Vahl) Nicholson / Phytochemical analysis and antioxidant, cytotoxic and antibacterial activities of Tabebuia serratifolia flowers (Vahl) Nicholson'

O presente estudo objetivou realizar a análise fitoquímica e avaliar as atividades antioxidante, citotóxica e antimicrobiana das flores de Tabebuia serratifolia (Ipê amarelo). A identificação de metabólitos secundários foi realizada por meio de testes qualitativos colorimétricos, a citotoxicidade pelo teste de letalidade frente à Artemia Salina, a atividade antioxidante foi avaliada pela capacidade de desativação do radical 2,2-difenil1-picrilhidrazila (DPPH) e a atividade antibacteriana foi avaliada pelo método de difusão em disco, frente aos microrganismos Escherichia coli, Staphylococcus aureus e Shigella sp. Os resultados revelaram a presença de flavonoides, saponinas e triterpenos e/ou esteroides. Observou-se a citotoxicidade (DL50=679 µg/mL), atividade antioxidante (CE50=86 mg/mL) e atividade antibacteriana sobre todas as cepas testadas (CIM=25 mg/mL).(AU)

The present study aimed to analyze the phytochemical compounds, and evaluate the cytotoxic, antioxidant and antimicrobial activities of Tabebuia serratifolia flowers. The phytochemical analysis was performed using qualitative colorimetric tests, the cytotoxicity by the Artemia salina lethality test, the antioxidant activity was evaluated by the ability to deactivate the 2.2-diphenyl-1-picrylhydrazyl radical (DPPH) and the antibacterial activity was evaluated by the disc diffusion method, against the microorganisms Escherichia coli, Staphylococcus aureus and Shigella sp. The results revealed the presence of flavonoids, saponins and triterpenes or steroids. It was observed the cytotoxicity (LD50=679 µg/mL), antioxidant activity (EC50=86 mg/mL) and antibacterial activity on all strains tested.(AU)

The anti-obesity effect of Taheebo (Tabebuia avellanedae Lorentz ex Griseb) extract in ovariectomized mice and the identification of a potential anti-obesity compound.

Estrogen deficiency-induced obesity has a high risk of visceral fat accumulation and body weight gain. It is also associated with many adverse health conditions. Taheebo extract from Tabebuia avellanedae has been recognized as playing several biological and pharmacological roles. Therefore, we investigated whether the intake of n-BuOH extract of Taheebo shows anti-obesity effect in ovariectomized (OVX) mice. After 16 weeks of feeding, the mice administrated with 0.5% n-BuOH extract of Taheebo showed significantly decreased body weight compared with that of the control mice, and the fat mass also showed a significant decrease. In 3T3-L1 cells, supplementation with n-BuOH extract of Taheebo significantly reduced the triglyceride (TG) levels. Furthermore, bioassay-guided purification of the n-BuOH extract based on the TG levels in 3T3-L1 cells led to the isolation of compound 2 (1-dehydroxy-3,4-dihydroaucubigenin). These results suggested that the anti-obesity effect of Taheebo extract is due to its capability in preventing the accumulation of adipocyte in mice. Taheebo extract might be a promising functional food resources capable of protecting against OVX-induced obesity.

Tabebuia roseoalba: In Vivo Hypouricemic and Anti-inflammatory Effects of Its Ethanolic Extract and Constituents.

Tabebuia species have several uses in folk medicine, including their use to treat inflammation and rheumatism. The aim of this study was to investigate whether the ethanolic extract of leaves from Tabebuia roseoalba and isolated compounds could be useful to decrease serum uric acid levels and restrain the gout inflammatory process. The compounds α-amyrin, ß-amyrin, sitosterol, and stigmasterol were isolated from the ethanolic extract. Rutin and caffeic acid were identified in the ethanolic extract by HPLC analysis. The anti-hyperuricemic effect, liver xanthine oxidoreductase inhibition, and anti-inflammatory activity of the ethanolic extract and isolated compounds were evaluated on hyperuricemic mice and on paw edema induced by monosodium urate crystals in mice. The ethanolic extract of leaves from T. roseoalba, ß-amyrin, and stigmasterol were able to reduce serum uric acid levels in hyperuricemic mice through inhibition of liver xanthine oxidase activity and significantly decreased the paw edema induced by monosodium urate crystals. The antioxidant activity of the ethanolic extract and its ability to inhibit xanthine oxidase were also evaluated in vitro. The ethanolic extract of leaves from T. roseoalba showed significant antioxidant activity in the three evaluated assays. Results were analyzed using GraphPad Prism 5.01. One-way ANOVA followed by Student's Newman-Keul's test was used to determine the significant differences between groups. The results show that the ethanolic extract of leaves from T. roseoalba, ß-amyrin, and stigmasterol can be promising agents for the treatment for gouty arthritis, hyperuricemia, and inflammation. Stigmasterol, ß-amyrin, and rutin contribute to the observed effects of the ethanolic extract of leaves from T. roseoalba.

Anti-inflammatory cyclopentene derivatives from the inner bark of Tabebuia avellanedae.

Six new cyclopentenyl esters, avellaneine A-F (1-4, 7, 8), two new cyclopentyl esters, avellaneine G, H (9, 10), along with two known cyclopentenyl esters were obtained from water extract of the inner bark of Tabebuia avellanedae Lorentz ex Griseb. The chemical structures of the new compounds were elucidated by spectroscopic techniques. The anti-inflammatory effects of these compounds were determined on LPS-stimulated RAW 264.7 cell line. Some of the tested compounds (2, 3, 4, 6, 7) reduced the NO production in a dose-dependent manner, while 6 and 7 decreased PGE2 production in a dose-dependent manner, without altering cell viability. Data presented in this research indicated that Tabebuia avellanedae's ethnopharmacological action of treating inflammatory diseases was based on the constituents which exert a significant anti-inflammatory effect on inflammatory responses.

Compostos fenólicos da casca de Handroanthus heptaphyllus (Mart. ) Mattos e efeitos do extrato aquoso no perfil lipídico, glicêmico e na lipoperoxidação em ratos diabéticos / Phenolic compounds from Handroanthus heptaphyllus (Mart. ) Mattos bark and effects of aqueous extract on lipid profile, glucose, and lipid peroxidation in diabetic rats

RESUMO A preocupação com o tratamento do Diabetes mellitus (DM) leva a uma crescente busca por terapias alternativas, como o uso de plantas medicinais, entre as quais, destaca-se o uso de Handroanthus heptaphyllus (Mart.) Mattos (popular Ipê roxo). Neste estudo realizamos a investigação química da presença de compostos fenólicos em H. heptaphyllus e o efeito do tratamento com o extrato aquoso da casca desta planta em parâmetros bioquímicos e nos níveis de lipoperoxidação tecidual e plasmática em animais diabéticos. Metodologia: Ratos Wistar machos foram submetidos ao desenvolvimento do quadro de DM por meio da administração intraperitoneal (IP) de Aloxano monohidrato (150 mg/Kg IP). Após a confirmação de hiperglicemia (>200 mg dL-1), os animais foram distribuídos nos grupos Diabético (D; n=6) e Diabético Tratado (DT; n=6). O tratamento consistiu na administração diária do extrato aquoso da casca de H. heptaphyllus via oral (v.o.) (150mg/Kg v.o.) por quatro semanas. O extrato aquoso foi analisado qualitativamente por cromatografia de camada delgada. Resultados: A análise qualitativa do extrato aquoso da casca indicou a presença de compostos fenólicos da subclasse flavonoides. O tratamento com o extrato aquoso reduziu a glicemia de jejum a partir da 3ª semana de tratamento, melhorou a resposta glicêmica à sobrecarga de glicose, diminuiu os níveis de triglicerídeos e índice LDL (Triglicerídeos/HDL). Estes resultados sugerem o uso terapêutico do extrato aquoso das cascas de H. heptaphyllus no tratamento do DM.

ABSTRACT Alternative medicine for diabetes mellitus (DM) treatment represents a growing research area on the use of medicinal plants, of which Handroanthus heptaphyllus (mart.) Mattos (popularly known as purple ipe) is most prominent. In this study, we investigated the presence of phenolic compounds and the effects of treatment with aqueous extract of in H. heptaphyllus in biochemical profile in plasma and the levels of lipid peroxidation in tissues and plasma in diabetic animals. Male Wistar rats were induced to develop DM through intraperitoneal (IP) administration of alloxan monohydrate (150 mg/kg IP). Once hyperglycemia (>200 mg dL-1) was confirmed, the animals were divided into the Diabetic (D; n=6) and Treated Diabetic (TD; n=6) groups. The TD group received daily administration (150 mg/kg v.o.) of aqueous extract of H. heptaphyllus for four weeks. The aqueous extract was also analyzed qualitatively by layer chromatography. Qualitative analysis of the aqueous extract of the bark indicated the presence of phenolic compounds from the flavonoid subclass. The treatment with the aqueous extract reduced fasting blood glucose levels from the third week of treatment on, improved the glycemic response to the glucose tolerance test, and lowered the levels of triglycerides and the LDL index (triglycerides/HDL). These findings suggest therapeutic use of the aqueous extract of H. heptaphyllus bark in treating DM.