Brasiliensic acid: in vitro cytotoxic and genotoxic, in vivo acute toxicity and in silico pharmacological prediction of a new promising molecule.

Brasiliensic acid (Bras) is a chromanone isolated from Calophyllum brasiliense Cambèss. bark extracts with confirmed potential activity on gastric ulcer and Helicobacter pylori infection. This study aimed to investigate the in vitro and in vivo toxicity of Bras and molecular docking studies on its interactions with the H. pylori virulence factors and selected gastric cancer-related proteins. Cytotoxicity was evaluated by alamarBlue© assay, genotoxicity by micronucleus and comet assays, and on cell cycle by flow cytometry, using Chinese hamster epithelial ovary cells. Bras was not cytotoxic to CHO-K1 cells, and caused no chromosomal aberrations, nor altered DNA integrity. Furthermore, Bras inhibited damages to DNA by H2O2 at 1.16 µM. No cell cycle arrest was observed, but apoptosis accounted for 31.2% of the cell death observed in the CHO-K1 at 24 h incubation of the IC50. Oral acute toxicity by Hippocratic screening test in mice showed no relevant behavioral change/mortality seen up to 1,000 mg/kg. The molecular docking approach indicated potential interactions between Bras and the various targets for peptic ulcer and gastric cancer, notably CagA virulence factor of H. pylori and VEGFR-2. In conclusion, Bras is apparently safe and an optimization for Bras can be considered for gastric ulcer and cancer.Communicated by Ramaswamy H. Sarma.

Spray dried extract of Calophyllum brasiliense Cambés produces a potent hypoglycemic effect and improves total serum cholesterol and triglycerides in diabetic rats / El extracto secado por pulverización de Calophyllum brasiliense cambés produce un potente efecto hipoglucémico y mejora el colesterol sérico total y los triglicéridos en ratas diabéticas / O extrato seco por aspersão de Calophyllum brasiliense Cambés produz um potente efeito hipoglicemiante e melhora o colesterol total e triglicérideos em ratos diabéticos

SUMMARY Introduction: The species Calophyllum brasiliense Cambés (Calophyllaceae) is widespread throughout Central and South America. The stem bark infusion is used for lowering blood glucose. Aim: To optimize the spray dry extract ofthis plant using a D-optimal experimental design. Materials and methods: As factors were used the air-drying speed (3.5-4.5 m3/h), the feed flow rate of the suspension (5-11 mL/ min), and the inlet air temperature (90-130 °C). The dried extract was characterized by measuring the phenolics and flavonoids content, moisture, the water activity, apparent densities, flowability, and compressibility. The antioxidant activity, the inhibitory activity of lipase and alpha-glycosidase, and the antiglycant activity of the spray dried extract (SDE) were evaluated. Subsequently, the hypoglycemic activity was evaluated in rats by monitoring the blood glucose level, triglycerides, and cholesterol. Results: Inlet air temperature and feed flow rate were the factors that most affected the yield and phenolic content. SDE showed a potent antioxidant effect (IC50 1.83 μg/mL), a potent a-glycosidase (IC50 74.45 μg/mL) and pancreatic lipase (IC50 27.33 μg/mL) inhibition. A potent antiglycation effect (IC50 9.45^g/mL) was also observed. Conclusion: the SDE showed a potent hypoglycemic effect at 100 mg/kg. These results suggest that SDE could activate four important pathways that can contribute to diabetes control.

Resumen Introducción: la especie Calophyllum brasiliense (Calophyllaceae) está muy extendida en Centro y Suramérica. La infusión del tronco reduce los niveles de glucosa en sangre. bjetivo: optimizar el extracto seco por aspersión (SDE) de esta planta utilizando un diseño experimental D-óptimal. Materiales y métodos: como factores se utilizaron la velocidad del gas secante (aire, 3,5-4,5 m3/h), la temperatura de entrada del aire fue 90-130 °C y la velocidad de alimentación, 5-11 mL/min. Se determinó el contenido de fenoles y flavonoides en el extracto seco, la humedad residual, la actividad del agua, las densidades aparentes, fluidez y compresibilidad. Se evaluó la actividad antioxidante e inhibidora de lipasa y alfa-glicosidasa y la actividad antiglicante. También se evaluó la actividad hipoglicemiante midiendo glucosa en sangre, triglicéridos y colesterol. Resultados: la temperatura del aire de entrada y la velocidad de alimentación afectaron, significativamente, el rendimiento y contenido de fenoles. El SDE mostró un potente efecto antioxidante (IC50 1,83 μg/mL), una potente inhibición de a-glicosidasa (IC50 74,45 μg/mL) y de lipasa pancreática (IC50 27,33 μg/ mL). Se observó un fuerte efecto antiglicante (IC50 9,45 μg/mL). Conclusiones: el SDE mostró un potente efecto hipoglicemiante a 100 mg/kg. Estos resultados sugieren que el SDE podría actuar activando cuatro vías importantes para el control de la diabetes.

RESUMO Introdução: a espécie Calophyllum brasiliense (Calophyllaceae) é amplamente distribuída na América do Sul e Central. A infusão da casca do caule reduz os níveis de glicose no sangue. Objetivo: otimizar o extrato seco por pulverização (SDE) desta planta usando um planejamento experimental D-ótimo. Materiais e métodos: a velocidade do gás de secagem ar (3,5-4,5 m3/h), a temperatura de entrada do ar (90-130 °C) e a taxa de alimentação (5-11 mL/min) foram usados como fatores. Foi determinado o teor de fenóis e flavonóides no extrato seco, a umidade residual, a atividade de água, as densidades aparentes, a fluidez e a compressibilidade. Avaliou-se a atividade antioxidante e a atividade inibitória de lipase e alfa-glicosidase, e a atividade antiglicante do extrato seco. A atividade hipoglicêmica foi avaliada em ratos diabeticos, medindo a glicose no sangue, triglicerídeos e colesterol. Resultados: a temperatura de entrada do ar e a taxa de alimentação afetaram significativamente o desempenho e o conteúdo de fenois. O SDE mostrou um potente efeito antioxidante (IC50 1,83 μg/mL), uma significativa inibição de a-glicosidase (IC50 74,45 ig/mL) e da lipase pancreática (IC50 27,33 μg/mL). Um forte efeito antiglicante também foi observado (IC50 9,45 μg/mL). O SDE mostrou um forte efeito hipogli-cemiente à concentração de 100 mg/kg. Conclusões: Esses resultados sugerem que o SDE poderia atuar ativando quatro vias importantes para o controle do diabetes.

Calanolides E1 and E2, two related coumarins from Calophyllum brasiliense Cambess. (Clusiaceae), displayed in vitro activity against amastigote forms of Trypanosoma cruzi and Leishmania infantum.

In the present work, the MeOH extract from stem barks of Calophyllum brasiliense Cambess. (Clusiaceae) displayed activity against amastigote forms of Trypanosoma cruzi and Leishmania infantum and was subjected to a bioactivity-guided fractionation to give two related coumarins - calanolides E1 (1) and E2 (2). Compounds 1 and 2 were actives to T. cruzi with EC50 values of 12.1 and 8.2 µM, respectively. When tested against L. infantum, the EC50 values were 37.1 and 29.1 µM, respectively. Compound 2, corresponding to anti isomer, showed the best selectivity index (SI) with values >24.4 to T. cruzi and >6.9 to L. infantum in comparison to the syn isomer 1. Furthermore, using an in silico multi-parametric prediction, both compounds did not contain any PAINS sub-structures. Therefore, these data suggest that coumarins 1 and 2 may contribute as scaffolds for the design of novel drug candidates for leishmaniasis and Chagas disease.

Mammea type coumarins isolated from Calophyllum brasiliense induced apoptotic cell death of Trypanosoma cruzi through mitochondrial dysfunction, ROS production and cell cycle alterations.

Chagas Disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi which affects 6-8 million people, mostly in Latin America. The medical treatment is based on two nitroimidazole compounds, which have limited effectiveness in the chronic phase of the disease and produce several adverse effects; consequently, there is an urgent need to develop new, safe, and effective drugs. Previous reports had shown that natural coumarins, especially mammea A/BA isolated from the tropical tree Calophyllum brasiliense, is a promissory molecule for developing new drugs, due to its potent activity, higher than benznidazole, selectivity, and its low toxicity in mice. However, its mode of action is still unknown. In the present work, we evaluated the mechanism of action of the coumarin mammea A/BA (93.6%), isolated from the tropical tree C. brasiliense on Querétaro strain (Tc1) of T. cruzi. This compound was tested in vitro on epimastigotes and trypomastigotes of T. cruzi for intracellular esterase activity, plasma membrane integrity, phosphatidylserine exposure, ROS production, mitochondrial membrane potential, caspase-like activity, DNA integrity, cell cycle and autophagy. Mammea A/BA showed a 50% lethal concentration (LC50) of 85.8 and 36.9 µM for epimastigotes and trypomastigotes respectively. It affected intracellular esterase activity, produced important plasma membrane damage and induced phosphatidylserine exposure. An increase in reactive oxygen species (ROS) and decrease in mitochondrial membrane potential were detected. Caspase-like activity was present in both parasite forms producing DNA integrity damage. This compound also induced a cell cycle arrest in the G1 phase and the presence of autophagy vacuoles. The above data suggest that mammea A/BA induce cell death of T. cruzi by autophagy and apoptosis-like phenomena and support our suggestion that mammea A/BA could be a promising molecule for the development of new drugs to treat Chagas Disease.

Coumarins isolated from Calophyllum brasiliense produce ultrastructural alterations and affect in vitro infectivity of Trypanosoma cruzi.

BACKGROUND: The current drugs for Chagas Disease caused by the protozoan Trypanosoma cruzi have limited therapeutic potential and are associated with serious side effects. Natural products can aid to develop new chemotherapeutic agents. Several natural coumarins, especially Mammea A/BA, have shown significant activity against T. cruzi and low toxicity on human lymphocytes, but its effectivity on a wide range of strains need to be tested, as well as to deepen in their mode of action and safety. HYPOTHESIS/PURPOSE: To discern the effects and explore the action mechanisms of mammea A/BA and a mixture of mammea coumarins isolated from Calophyllum brasiliense on Mexican strains of T. cruzi belonging to different genotypes and compare its effectivity with the drug benznidazole. STUDY DESIGN: We evaluated the trypanocidal activity in vitro of mammea A/BA (93.6%), and a mixture of coumarins, mammea A/BA + A/BB + A/BD (86:10:1%) on Mexican T. cruzi strains belonging to different genotypes Ninoa, Querétaro (TcI) and Ver6 (TcVI). MATERIAL AND METHODS: Mammea A/BA and the mixture of coumarins, were isolated from Calophyllum brasiliense, identified by proton NMR and purity determined by HPLC. The in vitro trypanocidal activity was evaluated on mobility, growth recovery, morphology and infectivity of T. cruzi. The cytotoxicity on mammalian cells was compared with benznidazole. The ultrastructure of the treated epimastigotes was analyzed by transmission electron microscopy (TEM). RESULTS: Mammea A/BA and the mixture of coumarins showed high trypanocidal activity, affecting the mobility, growth recovery, morphology, ultrastructure of epimastigotes, and drastically reduce trypomastigotes infectivity on Vero cells. These substances were four times more potent than benznidazole and showed low cytotoxicity and high selectivity index. The TEM showed severe alterations on the plasmatic membrane, nuclear envelope, as well as, mitochondrial swelling, that leads to the death of parasites. CONCLUSION: Mammea A/BA (93.6%) and a mixture of mammea A/BA + A/BB and A/BD (86: 10: 1%) isolated from the tropical tree C. brasiliense showed higher trypanocidal activity than the current drug benznidazole on three Mexican strains of T. cruzi. These compounds induced severe physiological and morphological alterations. These results suggest their possible use in preclinical studies.

Antinociceptive, anti-inflammatory, and central nervous system (CNS) effects of the natural coumarin soulattrolide.

Soulattrolide is a natural coumarin synthesized by the leaves of species of Calophyllum (Calophyllaceae) rain forest trees, including the American C. brasiliense, and the Asian C. teysmanii. Soulattrolide is a potent inhibitor of the reverse transcriptase from HIV-1 (RT-HIV-1), and active against Mycobacterium tuberculosis. However, the effects of this coumarins on other systems, remains to be evaluated. C. brasiliense is used in traditional medicine for the treatment of pain and inflammation. Therefore, we decided to explore the antinociceptive, anti-inflammatory activity of soulattrolide in mice, as well as, some of its possible effects on the CNS. Soulattrolide showed antinociceptive effects in the writhing test (ED50 = 33.8 mg/kg), as well as, in the formalin test with an ED50 = 7.9, and 22.1 mg/kg for Phases 1 and 2, respectively. The highest dose of soulattrolide (50 mg/kg) induced 40% of antinociception in the hot plate test. Regarding to anti-inflammatory activity, in the 12-O-Tetradecanoylphorbol-13-acetate (TPA) test, soulattrolide showed an IC50 = 1.81 µmol/ear, whereas in the myeloperoxidase assay, it showed an inhibition of 87% (1 µmol/ear). Soulattrolide showed sedative effects on the pentobarbital-induced sleeping time test, and the rotarod test, but lacked antidepressant activity on the tail suspension test. In conclusion, we report for the first time, the antinociceptive effects of soulattrolide in mice, like those of naproxen; soulattrolide also showed mild anti-inflammatory activity, as well as mild sedative and anxiolytic properties, therefore, it has also activity on the CNS.

Phytoremediation of Brazilian tree species in soils contaminated by herbicides.

The phytoremediation potential of Brazilian trees species Calophyllum brasiliense, Eremanthus crotonoides, Hymenaea courbaril, Inga striata, and Protium heptaphyllum was investigated for contaminated soils containing ametryn and hexazinone. Visual injury, chlorophyll content, plant height, leaf temperature, leaf number, and water-efficient use were evaluated. Residual herbicides at soil substrates were analyzed by LC/MS. Among the species C. brasiliense and H. courbaril were tolerant to both herbicides. P. Heptaphyllum presented tolerance at ametryn treatment. E. crotonoides, I. striata, and P. heptaphyllum died in hexazinone treatment. A high content of residual ametryn was found for E. crotonoides. In ametryn treatment, residual herbicide has decreased for C. brasiliense and E. crotonoides species. C. brasiliense highlighted among others becoming a good agent for phytoremediation of soils contaminated with traces of ametryn and hexazinone.

Jacareubin inhibits FcεRI-induced extracellular calcium entry and production of reactive oxygen species required for anaphylactic degranulation of mast cells.

Mast cells (MCs) are important effectors in allergic reactions since they produce a number of pre-formed and de novo synthesized pro-inflammatory compounds in response to the high affinity IgE receptor (FcεRI) crosslinking. IgE/Antigen-dependent degranulation and cytokine synthesis in MCs have been recognized as relevant pharmacological targets for the control of deleterious inflammatory reactions. Despite the relevance of allergic diseases worldwide, efficient pharmacological control of mast cell degranulation has been elusive. In this work, the xanthone jacareubin was isolated from the heartwood of the tropical tree Callophyllum brasilense, and its tridimensional structure was determined for the first time by X-ray diffraction. Also, its effects on the main activation parameters of bone marrow-derived mast cells (BMMCs) were evaluated. Jacareubin inhibited IgE/Ag-induced degranulation in a dose-response manner with an IC50 = 46 nM. It also blocked extracellular calcium influx triggered by IgE/Ag complexes and by the SERCA ATPase inhibitor thapsigargin (Thap). Inhibition of calcium entry correlated with a blockage on the reactive oxygen species (ROS) accumulation. Antioxidant capacity of jacareubin was higher than the showed by α-tocopherol and caffeic acid, but similar to trolox. Jacareubin shown inhibitory actions on xanthine oxidase, but not on NADPH oxidase (NOX) activities. In vivo, jacareubin inhibited passive anaphylactic reactions and TPA-induced edema in mice. Our data demonstrate that jacareubin is a potent natural compound able to inhibit anaphylactic degranualtion in mast cells by blunting FcεRI-induced calcium flux needed for secretion of granule content, and suggest that xanthones could be efficient anti-oxidant, antiallergic, and antiinflammatory molecules.

The validation of Calophyllum brasiliense ("guanandi") uses in Brazilian traditional medicine as analgesic by in vivo antinociceptive evaluation and its chemical analysis.

Calophyllum brasiliense is used as anti-inflammatory and analgesic in Brazilian traditional medicine. Thus, the main purpose of this study is to evaluate the antinociceptive effect of the chloroform fraction of C. brasiliense (CFCB) roots and to investigate its main mechanism of action. The antinociceptive effect of CFCB was evaluated in mice using acetic acid-induced writhing, formalin-induced paw licking, and hot-plate tests and capsaicin- and glutamate-induced nociception. Brasiliensic acid and 1,2-dimethoxyxanthone were isolated and evaluated in writhing test. The amount of 1,2-dimethoxyxanthone was determined in the fraction by UPLC-DAD. CFCB inhibited abdominal constrictions induced by acetic acid up to 97%, with an ID50 of 9.4 mg/kg (i.p.) and 131.8 mg/kg (p.o.). In the formalin test, CFCB impaired paw licking with an ID50 of 26.3 mg/kg for the first phase and 27.5 mg/kg for the second phase (i.p.). The painful response evoked by capsaicin and glutamate was significantly reduced (ID50 26.7 and 47.9 mg/kg, i.p.). The latency time was increased up to 76% at 60 mg/kg (i.p.) in the hot-plate test. 1,2-Dimethoxyxanthone was almost three times more potent (ID50 27.6 µmol/kg, i.p.) than brasiliensic acid (72.0 µmol/kg) in acetic acid-induced writhing test. The amount of the xanthone was estimated as 92.5 mg/g in the extract. CFCB inhibited the nociceptive response associated to several agents. TRPV1 channels play an important role in the mechanism of action of the fraction. In addition, 1,2-dimethoxyxanthone largely contributes to the antinociceptive effect of CFCB.

Risk assessment of Soulatrolide and Mammea (A/BA+A/BB) coumarins from Calophyllum brasiliense by a toxicogenomic and toxicological approach.

Calophyllum brasiliense (Calophyllaceae) is a tropical rain forest tree distributed in Central and South America. It is an important source of tetracyclic dipyrano coumarins (Soulatrolide) and Mammea type coumarins. Soulatrolide is a potent inhibitor of HIV-1 reverse transcriptase and displays activity against Mycobacterium tuberculosis. Meanwhile, Mammea A/BA and A/BB, pure or as a mixture, are highly active against several human leukemia cell lines, Trypanosoma cruzi and Leishmania amazonensis. Nevertheless, there are few studies evaluating their safety profile. In the present work we performed toxicogenomic and toxicological analysis for both type of compounds. Soulatrolide, and the Mammea A/BA + A/BB mixture (2.1) were slightly toxic accordingly to Lorke assay classification (DL50 > 3000 mg/kg). After a short-term administration (100 mg/kg/daily, orally, 1 week) liver toxicogenomic analysis revealed 46 up and 72 downregulated genes for Mammea coumarins, and 665 up and 1077 downregulated genes for Soulatrolide. Gene enrichment analysis identified transcripts involved in drug metabolism for both compounds. In addition, network analysis through protein-protein interactions, tissue evaluation by TUNEL assay, and histological examination revealed no tissue damage on liver, kidney and spleen after treatments. Our results indicate that both type of coumarins displayed a safety profile, supporting their use in further preclinical studies to determine its therapeutic potential.

Effect of a topical formulation containing Calophyllum brasiliense Camb. extract on cutaneous wound healing in rats.

This study evaluated the wound healing effects of topical application of an emulsion containing the HPLC-standardised extract from Calophyllum brasiliense Cambess (Clusiaceae) leaves in rats. The macroscopic analysis demonstrated that the wounds treated with the C. brasiliense emulsion healed earlier than the wounds treated with emulsion base and Dersani®. The percentage of wound healing in the group treated with the C. brasiliense emulsion was significantly higher than in the other groups at 7 and 14 days. On day 14, the animals treated with the C. brasiliense emulsion exhibited a 90.67% reduction of the wound areas. The histological evaluation revealed that on day 21, the group treated with the C. brasiliense emulsion exhibited a significant increase in fibroblasts compared with the other groups. Thus, the C. brasiliense emulsion had healing properties in the topical treatment of wounds and accelerated the healing process.

Effect of seed coat on the seed germination and seedling development of Calophyllum brasiliense Cambess. (Clusiaceae) / Efeito do envoltório na germinação da semente e no desenvolvimento de plântulas de Calophyllum brasiliense Cambess. (Clusiaceae)

This work aimed to study the effect of the Calophyllum brasiliense seed coat on the seed germination process. To this end, three experiments were conducted in laboratory, greenhouse and screenhouse. From a total of six treatments, five are related to the seed coat (mechanical scarification; mechanical scarification followed by 2 hours in water, chemical scarification, hot water immersion and complete seed coat removal) and one control. Laboratory and greenhouse experiments were conducted in a completely randomized design (CRD). Screenhouse experiment was conducted in a completely randomized block design (RBD). We evaluated the total percentage, the speed index and the average time of germination or emergence. Data were subjected to analysis of variance and means compared by LSD test, at 5%. Under the conditions of this work, it was possible to infer that, in laboratory, mechanical scarification followed by 2 hours in water increases the proportion and germination speed index (GSI), in the greenhouse, the complete seed coat removal increases the percentage and emergence speed index (ESI), and in the screenhouse, mechanical scarification followed by 2 hours in water and chemical scarification presented the best results. The average germination time was not significantly different in the three experiments evaluated.

Objetivou-se com este trabalho estudar o efeito do envoltório da semente de Calophyllum brasiliense no processo de germinação. Foram montados três experimentos, sendo estes conduzidos em laboratório, casa de vegetação e telado. Avaliaram-se seis tratamentos, sendo cinco relacionados ao envoltório (escarificação mecânica; escarificação mecânica seguido por 2h em água; escarificação química; imersão em água quente; e retirada total do envoltório) e a testemunha. Os experimentos em laboratório e casa de vegetação foram conduzidos em delineamento inteiramente casualizado. No telado, o experimento foi conduzido em delineamento em blocos casualizados. Avaliaram-se a percentagem total; o índice de velocidade e o tempo médio de germinação ou emergência. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste t (LSD) a 5% de probabilidade. Foi possível inferir que no laboratório, a escarificação mecânica, seguido por 2h em água, aumenta a percentagem e o índice de velocidade de germinação (IVG); na casa de vegetação, a retirada total do envoltório aumenta a percentagem e o índice de velocidade de emergência (IVE); e no telado, a escarificação mecânica, seguida por 2h em água, e a escarificação química apresentam os melhores resultados. O tempo de germinação não apresentou diferença significativa nos três experimentos avaliados.

Evaluation of toxicity of Calophyllum brasiliense stem bark extract by in vivo and in vitro assays.

ETHNOPHARMACOLOGICAL RELEVANCE: Calophyllum brasiliense Camb., Clusiaceae, is commonly known as "guanandi" and its stem bark is used in Brazilian traditional medicine to treat rheumatism, vein problems, hemorrhoids and gastric ulcers. The aim of this study was to evaluate the toxicity of hexane extract of Calophyllum brasiliense stem bark (HECb) using in vitro and in vivo experimental models. MATERIALS AND METHODS: In vitro toxicity was evaluated by Alamar Blue cytotoxicity assay and micronucleus test, using Chinese hamster ovary (CHO-k1) epithelial cells. in vivo toxicity was evaluated by oral acute and subchronic toxicity assays. In the oral acute toxicity screening, a single dose of HECb was administered to mice at doses ranging from 250 to 1000 mg/kg. In the subchronic study, HECb was administered orally for 30 days to Wistar rats at doses of 100 mg/kg and 500 mg/kg. Phytochemical analyses were performed by HPLC/UV-vis, secondary metabolites were quantified by spectrophotometric methods. RESULTS: HECb presented IC50=119.94±4.31 µg/mL after a 24 h cytotoxicity test using CHO-k1 cells, showing low cytotoxicity. However, when the cells were exposed to HECb for 72 h, the IC50 value was 8.39±2.00 µg/mL, showing in this case, a pronounced cytotoxic effect. In the oral acute toxicity studies, doses up to 500 mg/kg of HECb did not cause any changes in both male and female mice. At 1000 mg/kg, male mice showed signs typical of depression and stimulation that were reversed at 72 h. Besides, female mice were more sensitive to the toxic effect of HECb at 1000 mg/kg, which initially presented typical agitation signals, followed by depression signals, leading to death of all the animals at 24h. In subchronic assay with rats, HECb administered orally at doses of 100 and 500 mg/kg did not cause significant changes in all clinical parameters evaluated. Histopathological analyses showed no deleterious effect in the vital organs of rats. Preliminary phytochemical analysis revealed the presence of phenolic compounds, steroids, and volatile coumarins. Analysis by HPLC showed two major peaks characteristic of chromanones. CONCLUSIONS: In vitro toxicological tests showed that HECb exhibited cytotoxicity especially after 72 h of exposition, and mutagenicity on the highest tested dose. The in vivo studies demonstrated that HECb produced some toxicity signs at the highest dose tested, particularly, in the acute toxicity test but showed no significant signs of toxicity in the subchronic assay. Based on these and previous pharmacological studies, it is possible to say that HECb did not exhibit significant toxicity at its effective dose. This suggests that HECb is relatively safe in humans at its effective dose.

Anti-Mycobacterium tuberculosis activity and cytotoxicity of Calophyllum brasiliense Cambess (Clusiaceae)

We evaluated the in vitro anti-Mycobacterium tuberculosis activity and the cytotoxicity of dichloromethane extract and pure compounds from the leaves of Calophyllum brasiliense. Purification of the dichloromethane extract yielded the pure compounds (-) mammea A/BB (1), (-) mammea B/BB (2) and amentoflavone (3). The compound structures were elucidated on the basis of spectroscopic and spectrometric data. The contents of bioactive compounds in the extracts were quantified using high performance liquid chromatography coupled to an ultraviolet detector. The anti-M. tuberculosis activity of the extracts and the pure compounds was evaluated using a resazurin microtitre assay plate. The cytotoxicity assay was performed in J774G.8 macrophages using the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colourimetric method. The quantification of the dichloromethane extract showed (1) and (2) at concentrations of 31.86 ± 2.6 and 8.24 ± 1.1 µg/mg of extract, respectively. The dichloromethane and aqueous extracts showed anti-M. tuberculosis H37Rv activity of 62.5 and 125 µg/mL, respectively. Coumarins (1) and (2) showed minimal inhibitory concentration ranges of 31.2 and 62.5 µg/mL against M. tuberculosis H37Rv and clinical isolates. Compound (3) showed no activity against M. tuberculosis H37Rv. The selectivity index ranged from 0.59-1.06. We report the activity of the extracts and coumarins from the leaves of C. brasiliense against M. tuberculosis.

Molecular mechanisms involved in the cytotoxicity induced by coumarins from Calophyllum brasiliense in K562 leukaemia cells.

OBJECTIVES: The aim of this study was to determine the cellular and molecular mechanisms of cell death induced by mammea A/BA and A/BB (3 : 1) on K562 cells. METHODS: These compounds were isolated from Calophyllum brasiliense and its cytotoxicity was tested using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell death was evaluated by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and immunocytofluorescence of active caspase-3. Genotoxicity was tested using comet assay. Lastly, a chemoinformatic analysis was performed with Osiris-Molinspiration software. KEY FINDINGS: The mixture of mammea A/BA and A/BB (3 : 1) showed cytotoxic activity against K562 cells (IC50 = 43.5 µm). TUNEL positive cells and active caspase-3 were detected after treatment. Genotoxicity of mammea A/BA and A/BB on K562 was detected since first hour of treatment. Additionally, mammea A/BA and A/BB were found to be in compliance with Lipinski 'rule of 5' suggesting that they possess strong potential of druglikeness. CONCLUSIONS: The overall results confirm and extend the knowledge about coumarins as an important resource of antitumor drugs, and indicate that these compounds could be used in further preclinical studies against leukaemia.

El árbol tropical Calophyllum brasiliense: una revisión botánica, química y farmacológica / The tropical tree Calophyllum brasiliense: a botanical, chemical and pharmacological review

Antecedentes: Calophyllum brasiliense Cambess. Es un árbol de la familia Calophyllaceae, separada recientemente de Clusiaceae (Guttiferae). Se distribuye ampliamente en selvas tropicales lluviosas del continente americano, desde Brasil hasta México. Esta especie sintetiza diversos metabolitos secundarios en hojas, flores, frutos, corteza y raíz, tales como cumarinas, cromanonas, xantonas, terpenos, flavonoides y compuestos fenólicos, los cuales presentan múltiples propiedades biológicas. Objetivos: Ofrecer una visión general de las características botánicas, químicas y farmacológicas de C. brasiliense, así como evidencias químicas, anatómicas y genéticas que sugieren la existencia de quimiotipos (fenotipos químicos) en la especie. Métodos: Se revisó la información disponible en las bases de datos NCBI y SciFinder®, se seleccionaron investigaciones relevantes que permitieron conocer los compuestos químicos aislados y su actividad biológica. Resultados: Entre los compuestos sintetizados por C. brasiliense destacan calanólidos e inofilums, especialmente el (+)-calanólido A, como inhibidores potentes de la enzima transcriptasa reversa del virus de inmunodeficiencia humana tipo 1 (VIH-1) y baja toxicidad a linfocitos humanos. El (+)-calanólido A, una dipiranocumarina tetracíclica, podría ser el primer fármaco de origen natural aprobado por la FDA (EUA) en el tratamiento del VIH/SIDA. Otros compuestos, tales como cumarinas tipo mammea, cromanonas, xantonas y triterpenos, mostraron actividad contra protozoarios, células tumorales humanas, como bactericidas y antiespasmódicos. La actividad más importante de cumarinas tipo mammea es contra protozoarios como Leishmania y Trypanosoma. En relación a L. amazonensis, destacó (-)-mammea A/BB presentando buena actividad y selectividad contra amastigotes y promastigotes, y baja toxicidad en macrófagos humanos. La (-)-mammea A/BA, y las xantonas preniladas mostraron alta citotoxicidad sobre líneas celulares tumorales humanas y T. cruzi. Las evidencias químicas, anatómicas y genéticas indican que existen quimiotipos en C. brasiliense, sugiriendo un proceso de especiación en curso en el taxón. Las secuencias ribosomales (ITS) discriminaron al quimiotipo 1 (produce coumarinas tipo mammea) de los quimiotipos 2 y 3 (biosintetizan calanólidos e inofilums), siendo útiles como posibles códigos de barras. Conclusiones: El adecuado manejo de C. brasiliense mediante técnicas silvícolas y biotecnológicas, así como el conocimiento científico y tecnológico, podrían aportar soluciones a países en desarrollo, por ejemplo mediante producción de fitomedicamentos, a enfermedades como el VIH/ SIDA, Leshmaniasis y la Enfermedad de Chagas.

Rationale: Calophyllum brasiliense Cambess. Is a tree belonging to Calophyllaceae family, recently separated from Clusiaceae (= Guttiferae). This species is widely distributed in the Tropical Rain Forests of the American continent, from Brazil to Mexico. It synthesizes a wide variety of secondary metabolites isolated from leaves, flowers, fruits, bark and roots, such as coumarins, chromanones, xanthones, terpenes,flavonoids and phenolic compounds, which exhibit multiple biological properites. Objective: To provide a comprehensive view of the botanical, chemical and pharmacological characteristics of C. brasiliense, and to present chemical, anatomical and genetic evidences supporting the notion of chemotypes (chemical phenotypes) in this species. Methods: Information available in the databases NCBI and SciFinder® was reviewed, and relevant investigations were selected regarding to chemical compounds isolated and their biological activity. Results: Among compounds synthesized by C. brasiliense, calanolides and inophyllums stand out, specially (+)-calanolide A, since these can inhibit reverse transcriptase of human immunodeficiency virus type 1 (HIV-1). (+)-Calanolide A, a tetracyclic dipyranocoumarin, could be the first drug of natural origin approved by the FDA (US) in the treatment of HIV/AIDS. Other compounds, such as mammea type-coumarins, chromanones, xanthones, and triterpenes showed antitumor, antiparasitic, antibacterial and antispasmodic activity. Most important activity of mammea type-coumarins is against protozoa, such as Leishmania, and Trypanosoma. Regarding to L. amazonensis, (-)-mammea A/BB stands out, being highly potent and selective against amastigotes, and promastigotes, but poorly toxic to human macrophages. (-)-Mammea A/BA as well as prenylated xanthones showed high citotoxicity against human tumor cell lines and T. cruzi. The chemical, anatomical and genetical evidences supported the idea of chemotypes in C. brasiliense, suggesting a current process of speciation in this taxon. The ribosomal ITS sequences discriminate chemotype 1 (produces mammea type coumarins) from chemotypes 2 and 3(synthesize calanolides and inophyllums) being useful like possible barcodes. Conclusions: The proper management of Calophyllum brasiliense with forestry and biotechnological methods, as well as scientific and technological knowledge, could provide solutions to developing countries, for instance through the production of phytomedicines against HIV/AIDS, and illnesses caused by protozoa such as Leshmaniasis and Chaga's Disease.

Study of dissolution profiles and desintegration of capsules containing the dried hydroethanolic extract of Calophyllum brasiliense

Calophyllum brasiliense Cambess, Calophyllaceae, is of great interest in folk medicine and is used in the treatment of various diseases such as diabetes. Granules containing the hydroethanolic extract from the stem bark of C. brasiliense were obtained. The polyphenol content was standardized, and the average weight, disintegration, and the dissolution profiles of the capsules were determined after encapsulation. The capsules had an average weight of 574.5±8.0 mg. In vitro tests showed that the most efficient disintegration profile was in hydrochloric acid buffer (pH 1.2), with a capsule disintegration time within 9 min. The dissolution analysis showed a better uniformity of capsule content release when the test was performed in a hydrochloric acid buffer (pH 1.2), with a maximal release rate at 15 min (giving a polyphenol content of 4.38%, which corresponds to a concentration of 0.0080 mg/mL). In distilled water, the maximal release was reached at 20 min (giving a polyphenol content of 5.41%, which is equivalent to 0.0105 mg/mL). In phosphate buffer, the maximal release of capsule contents was reached at the end of the dissolution assay (30 min), with the lowest amount of released polyphenols (3.61%, which corresponds to a concentration of 0.0070 mg/mL). The encapsulated form of the hydroethanolic extract of C. brasiliense was shown to have the necessary traits of a desirable delivery agent, and the dissolution test was an effective analysis of this material's polyphenol release profile for the specific dosage form.

Evaluation of the proliferative activity of methanol extracts from six medicinal plants in murine spleen cells

A number of natural compounds have been used as immunomodulatory agents, enabling the function of the immune system to be modified by stimulating or suppressing it. There has been increasing interest in the study of therapeutic action of plant extracts regarding their immunomodulatory activity. The aim of this study was to identify and evaluate the action of extracts of the medicinal plants Calophyllum brasiliense, Ipomoea pes-caprae, Matayba elaeagnoides, Maytenus robusta, Rubus imperialis and Vernonia scorpioides on the development of spleen cells from mice, using the in vitro cellular proliferation assay. The cells, obtained by mechanical rupture of mice spleen (5x10(4) cells/mL), were incubated with methanol extracts (10, 50, 100 and 200 µg/mL) and phytohemagglutinin (PHA, 5 µg/mL). The basal control for proliferation consisted of cells alone, while the positive control consisted of cells and PHA. The cell culture was kept at 37 ºC in 5 percent CO2 for 72 hours, and cell proliferation was revealed by the blue tetrazolium reduction assay (MTT). The results were expressed as percentage of growth and were analyzed using the Kruskal-Wallis and Mann-Whitney tests. The C. brasiliense, I. pes-caprae and M. elaeagnoides extracts showed dose-dependent induction of cell proliferation, with a significant increase in cell proliferation (p<0.03) and percentage growth of 88.2 percent, 73.1 percent and 52.7 percent, respectively, suggesting T lymphocyte stimulation. By contrast, M. robusta, R. imperialis and V. scorpioides extracts showed significance only with a negative percentage of growth, suggesting inhibition of cell proliferation (p<0.04). Further biomonitoring studies will enable the fractions and isolated substances responsible for the immunomodulatory activities to be identified.

Várias substâncias de origem natural têm sido utilizadas como agentes imunomoduladores, permitindo modificar a função do sistema imune e propiciando o estudo de atividades terapêuticas de extratos de plantas. Este trabalho objetivou identificar a atividade imunomodulatória dos extratos de seis plantas medicinais da flora brasileira, Calophyllum brasiliense, Ipomoea pes-caprae, Matayba elaeagnoides, Maytenus robusta, Rubus imperialis e Vernonia scorpioides, sobre a proliferação de células esplênicas de camundongos. As células esplênicas murinas obtidas por ruptura mecânica do baço (5x14³ células/mL) foram incubadas com os extratos metanólicos das plantas (10, 50, 100, 200 µg/mL) e fito-hemaglutinina (PHA, 5 µg/mL). O controle basal de proliferação foi constituído de células apenas e o controle positivo formado por células e PHA. O cultivo celular foi mantido a 37 ºC, 5 por cento de CO2, 72 horas, com quantificação da proliferação celular pelo ensaio de redução do azul de tetrazólio. Os resultados expressos em percentagem de crescimento foram analisados pelos testes de Kruskal-Wallis e Mann-Whitney. Os extratos de C. brasiliense, I. pes-caprae e M. elaeagnoides mostraram indução dose-dependente da proliferação celular (p<0,03), com percentagem de crescimento de, respectivamente, 88,2 por cento, 73,1 por cento e 52,7 por cento, sugerindo estímulo de linfócitos T. Contrariamente, os extratos de M. robusta, R. imperialis e V. scorpioides apresentaram significância apenas com percentagem de crescimento negativa, indicando inibição da proliferação celular (p<0,04). A continuidade no estudo biomonitorado permitirá a identificação das frações e substâncias isoladas responsáveis pelas atividades imunomoduladoras.

Trypanocidal constituents in plants: 7. Mammea-type coumarins

Calophyllum brasiliense and Mammea americana (Clusiaceae) are two trees from the tropical rain forests of the American continent. A previous screening showed high trypanocidal activity in the extracts of these species. Several mammea-type coumarins, triterpenoids and biflavonoids were isolated from the leaves of C. brasiliense. Mammea A/AA was obtained from the fruit peels of M. americana. These compounds were tested in vitro against epimastigotes and trypomastigotes of Trypanosoma cruzi, the etiologic agent of Chagas disease. The most potent compounds were mammea A/BA, A/BB, A/AA, A/BD and B/BA, with MC100 values in the range of 15 to 90 g/ml. Coumarins with a cyclized ,-dimethylallyl substituent on C-6, such as mammea B/BA, cyclo F + B/BB cyclo F, and isomammeigin, showed MC100 values > 200 g/ml. Several active coumarins were also tested against normal human lymphocytes in vitro, which showed that mammea A/AA and A/BA were not toxic. Other compounds from C. brasiliense, such as the triterpenoids, friedelin, canophyllol, the biflavonoid amentoflavone, and protocatechuic and shikimic acids, were inactive against the epimastigotes. The isopropylidenedioxy derivative of shikimic acid was inactive, and its structure was confirmed by X-ray diffraction. Our results suggest that mammea-type coumarins could be a valuable source of trypanocidal compounds.