Reverted effect of mesenchymal stem cells in glioblastoma treated with agathisflavone and its selective antitumoral effect on cell viability, migration, and differentiation via STAT3.

Glioblastoma is the most lethal tumor of the central nervous system, presenting a very poor prognostic, with a survival around 16 months. The interaction of mesenchymal stem cells and tumor cells has been studied, showing a bias in their role favoring or going against aggressiveness. Natural products such as flavonoids have showed their anticancer properties and the synergic potential with the activation of microenvironment cells to inhibit tumor progression. Agathisflavone is a flavonoid studied in neurodegenerative diseases and cancer. The present study investigated the effect of flavonoid in the viability of heterogeneous glioblastoma (GBM) cells considering a coculture or conditioned medium of mesenchymal stem cells (MSCs) effect, as well as the dose-dependent effect of this flavonoid in tumor migration and differentiation via STAT3. Agathisflavone (3-10 µM) induced dose-dependent toxicity to GL-15 and U373 human GBM cells, since 24 h after treatments. It was not toxic to human MSC but modified the pattern of interaction with GBM cells. Agathisflavone also inhibited migration and increased differentiation of human GBM cells, associated with the reduction on the expression of STAT3. These results demonstrate that the flavonoid agathisflavone had a direct anti-glioma effect. However, could be observed its effect in MSCs response that may have an impact in controlling GBM growth and aggressiveness, an important factor to consider for new therapies.

Bergenin Reduces Experimental Painful Diabetic Neuropathy by Restoring Redox and Immune Homeostasis in the Nervous System.

Diabetic neuropathy is a frequent complication of diabetes. Symptoms include neuropathic pain and sensory alterations-no effective treatments are currently available. This work characterized the therapeutic effect of bergenin in a mouse (C57/BL6) model of streptozotocin-induced painful diabetic neuropathy. Nociceptive thresholds were assessed by the von Frey test. Cytokines, antioxidant genes, and oxidative stress markers were measured in nervous tissues by ELISA, RT-qPCR, and biochemical analyses. Single (3.125-25 mg/kg) or multiple (25 mg/kg; twice a day for 14 days) treatments with bergenin reduced the behavioral signs of diabetic neuropathy in mice. Bergenin reduced both nitric oxide (NO) production in vitro and malondialdehyde (MDA)/nitrite amounts in vivo. These antioxidant properties can be attributed to the modulation of gene expression by the downregulation of inducible nitric oxide synthase (iNOS) and upregulation of glutathione peroxidase and Nrf2 in the nervous system. Bergenin also modulated the pro- and anti-inflammatory cytokines production in neuropathic mice. The long-lasting antinociceptive effect induced by bergenin in neuropathic mice, was associated with a shift of the cytokine balance toward anti-inflammatory predominance and upregulation of antioxidant pathways, favoring the reestablishment of redox and immune homeostasis in the nervous system. These results point to the therapeutic potential of bergenin in the treatment of painful diabetic neuropathy.

Cytotoxic, Antitumor and Toxicological Profile of Passiflora alata Leaf Extract.

Passiflora alata or passion fruit is a native flowering plant from Amazon, geographically spread from Peru to Brazil. The plant has long been used in folks medicine for its pharmacological properties and is included in the Brazilian Pharmacopoeia since 1929. The aim of this study was to evaluate the potential cytotoxic and antitumor activities of Passiflora alata leaf extract (PaLE) in S180-tumor bearing mice. The percentage of cell proliferation inhibition (% CPI) and IC50 in relation to 4 tumor cell lines were determined in PC3, K-562, HepG2 and S180 cell lines using the MTT assay. PaLE showed a CPI > 75% and greater potency (IC50 < 30 µg/mL) against PC3 and S180 cell lines. PaLE showed antitumor activity in treatments intraperitoneally (36.75% and 44.99% at doses of 100 and 150 mg/kg/day, respectively). Toxicological changes were shown in the reduced body mass associated with reduced food consumption, increased spleen mass associated with histopathological increase in the white pulp of the spleen and increased number of total leukocytes with changes in the percentage relationship between lymphocytes and neutrophils. Our outcomes corroborate the conclusion that PaLE has antitumor activity in vitro and in vivo with low toxicity.

Absence of toxicity in Swiss mice following treatment with 7-acetoxy-4-aryl-3,4-dihydrocoumarin: Acute and repeated-dose toxicity study.

Neoflavonoids, which are classified as 4-arylcoumarin (neoflavone), 3,4-dihydro-4-arylcoumarin and neoflavene, have been the subject of a number of studies with respect to their therapeutic potential and, despite promising in vitro, ex vivo and in vivo pharmacological activities, there is a lack of studies demonstrating their toxicological properties. Therefore, this study aims to evaluate the acute (14 days) and repeated-dose (28 days) toxicity of synthetic neoflavonoid 7-acetoxy-4-aryl-3,4-dihydrocoumarin in Swiss mice through parameters related to changes in body weight, food and water intake, hematological and biochemical parameters. Toxicity studies using acute doses (300 and 2000 mg/kg) and repeated doses (250, 500 and 1000 mg/kg) orally were carried out as per Organization for Economic Co-operation and Development (OECD) guidelines 423 and 407, respectively. Based on the results of this study, treatment with 7-acetoxy-4-aryl-3,4-dihydrocoumarin was found to not cause clinical adverse symptoms and mortality in any animal used in the acute and repeated-dose toxicity study. In addition, no significant changes were observed in body weight and internal organs, food and water intake, hematological and biochemical parameters, compared to control group. Therefore, these results provide an initial understanding regarding the toxicity profile of 7-acetoxy-4-aryl-3,4-dihydrocoumarin, which can be considered a neoflavonoid with toxicity seen at doses higher than 2000 mg/kg in Swiss mice.

Terpene Esters from Natural Products: Synthesis and Evaluation of Cytotoxic Activity.

Natural steroids and triterpenes such as b-sitosterol, stigmasterol, lupeol, ursolic and betulinic acids were transformed into its hexanoic and oleic esters, to evaluate the influence of chemical modification towards the cytotoxic activities against tumor cells. The derivatives were evaluated against five tumor cell lines [OVCAR-8 (ovarian carcinoma); SF-295 (glioblastoma); HCT-116 (colon adenocarcinoma); HL-60 (leukemia); and PC-3 (prostate carcinoma)] and the results showed only betulinic acid hexyl ester exhibits cytotoxic potential activity.

Phytochemical profile and qualification of biological activity of an isolated fraction of Bellis perennis.

This study describes the isolation and identification of apigenin-7-O-ghicopyranoside, a flavonoid isolated from the flowers of Bellis perennis L., Asteraceae, an species with a broad spectrum of biological activities. The in vitro antioxidant activity and the inhibition of the enzyme acetylcholinesterase were evaluated. The flavonoid showed strong in vitro antioxidant potential, because of the capacity of removal of hydroxyl radicals and nitric oxide, and also prevented the formation of thiobarbituric acid-reactive substances. These parameters were inhibited at the highest concentration of ApG at rates of 77.7%, 72% and 73.4%, respectively, in addition to inhibiting acetylcholinesterase, suggesting potential use in the treatment of neurodegenerative diseases.

Volatile organic compounds obtained by in vitro callus cultivation of Plectranthus ornatus Codd. (Lamiaceae).

Plectranthus spp (Lamiaceae) are plants of economic importance because they are sources of aromatic essential oils and are also cultivated and several species of this genus are used as folk medicines. This paper describes the effects of different concentrations of the 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthaleneacetic acid (NAA) on the induction of callus from nodal segments of Plectranthus ornatus Codd and in the production of volatile organic compounds (monoterpenes and sesquiterpenes). The 20 and 40 day calli were subjected to solid phase micro extraction (HS-SPME) and submitted to GCMS analysis. Variations in VOCs between the samples were observed and, a direct relationship was observed between of the major constituent detected (α-terpinyl acetate) and the monoterpenes α-thujene, α-pinene, ß-pinene, camphene, sabinene and α-limonene that were present in the volatile fractions. Besides α-terpinyl acetate, isobornyl acetate and α-limonene were also major constituents. Variations were observed in VOCs in the analyzed periods. The best cultivation media for the production of VOCs was found to be MS0 (control). Moderate success was achieved by treatment with 2.68 µM and 5:37 µM NAA (Group 2). With 2,4-D (9.0 µM), only the presence of α-terpinyl acetate and isocumene were detected and, with 2.26 µM of 2,4-D was produced mainly α-terpinyl acetate, α-thujene and ß-caryophyllene (16.2%). The VOC profiles present in P. ornatus were interpreted using PCA and HCA. The results permitted us to determine the best cultivation media for VOC production and, the PCA and HCA analysis allowed us to recognize four groups among the different treatments from the compounds identified in this set of treatments.

In vitro acetylcholinesterase activity of peptide derivatives isolated from two species of Leguminosae.

CONTEXT: Cratylia mollis Martius ex Benth. and Cenostigma macrophyllum Tul. (Leguminosae) are both endemic Brazilian plants and they are used by the natives as medicinal plants, and the leaves of C. mollis are also employed as forage for cattle during the dry season of region. OBJECTIVE: Isolation of the compounds responsible for the acetylcholinesterase (AChE) inhibition from the CHCl3 active extract. MATERIALS AND METHODS: Two peptidic compounds were isolated by chromatographic techniques from the CHCl3 extract of the leaves of C. mollis and C. macrophyllum. They were identified by spectrometric data analysis (MS and NMR) and they were subjected to AChE inhibition employing Ellman's test. RESULTS: The peptides were identified as N-benzoylphenylalaninoyl-phenlyalaninolacetate (aurentiamide acetate) (1) and N-benzoylphenylalaninyl-N-benzoylphenylalaninate (2). Both peptides 1 and 2 exhibit AChE inhibition, with IC50 values equal to 111.34 µM and 137.6 µM, respectively. DISCUSSION AND CONCLUSION: Compound 1 (aurentiamide acetate) has rarely been isolated from the Leguminosae family, and N-benzoylphenylalaninyl-N-benzoylphenylalaninate (2) is a compound that has never previously been isolated from this family. Compound 1 is shown to be a potent inhibitor of AChE, with IC50 values similar to the physostigmine control (141.51 µM).

Bioactive oleanane, lupane and ursane triterpene acid derivatives.

Betulinic, ursolic and oleanolic acids isolated from the aerial parts of Eriope blanchetii (Lamiaceae) were subjected to different esterification reactions, yielding 12 C-3 position ester derivatives. All compounds were identified using spectroscopic techniques, such as IR, 1H-NMR and MS. The derivatives were further investigated for their antioxidant level, Artemia salina lethality and antimicrobial activity.

Acetylcholinesterase inhibitory activity of Ocotea pomaderroides extracts: HPLC-MS/MS characterization and molecular modeling studies.

The present work describes the acetylcholinesterase inhibitory activity of Ocotea pomaderroides extracts besides the chemical composition of chromatographic fractions. The hexane, dichloromethane and ethyl acetate extract soluble fractions showed high Electrophorus electricus acetylcholinesterase (EelAChE) inhibition (92.18, 71.86 and 74.25%, respectively) while the butanolic and aqueous extracts showed moderate to low activities (44.48 and 20.74%, respectively). The high-performance liquid chromatography coupled with electrospray ionization multiple-stage mass spectrometry (HPLC-ESI-MSn) analysis led to the identification of the alkaloids and flavonol glycoside derivatives present in these extracts. The binding profile of the alkaloids and their atomic effect on 3D structure of Electrophorus electricus AchE (EelAChE) were assessed with molecular modeling.

Agathisflavone as a Single Therapy or in Association With Mesenchymal Stem Cells Improves Tissue Repair in a Spinal Cord Injury Model in Rats.

Agathisflavone is a flavonoid with anti-neuroinflammatory and myelinogenic properties, being also capable to induce neurogenesis. This study evaluated the therapeutic effects of agathisflavone-both as a pharmacological therapy administered in vivo and as an in vitro pre-treatment aiming to enhance rat mesenchymal stem cells (r)MSCs properties-in a rat model of acute spinal cord injury (SCI). Adult male Wistar rats (n = 6/group) underwent acute SCI with an F-2 Fogarty catheter and after 4 h were treated daily with agathisflavone (10 mg/kg ip, for 7 days), or administered with a single i.v. dose of 1 × 106 rMSCs either unstimulated cells (control) or pretreated with agathisflavone (1 µM, every 2 days, for 21 days in vitro). Control rats (n = 6/group) were treated with a single dose methylprednisolone (MP, 60 mg/kg ip). BBB scale was used to evaluate the motor functions of the animals; after 7 days of treatment, the SCI area was analyzed after H&E staining, and RT-qPCR was performed to analyze the expression of neurotrophins and arginase. Treatment with agathisflavone alone or with of 21-day agathisflavone-treated rMSCs was able to protect the injured spinal cord tissue, being associated with increased expression of NGF, GDNF and arginase, and reduced macrophage infiltrate. In addition, treatment of animals with agathisflavone alone was able to protect injured spinal cord tissue and to increase expression of neurotrophins, modulating the inflammatory response. These results support a pro-regenerative effect of agathisflavone that holds developmental potential for clinical applications in the future.

Antinociceptive properties of bergenin.

Bergenin (1) is a C-glucoside of 4-O-methylgallic acid with known antiarthritic activity attributed to modulation of cytokine production. The present study was undertaken to evaluate whether 1 has antinociceptive properties in models of inflammatory pain and to investigate its possible mechanisms of action. Pretreatment with 1 (12.5-100 mg/kg, ip) produced a dose-related inhibition of acetic acid-induced writhing in mice. Furthermore, treatment with 1 (50 and 100 mg/kg) inhibited both the early and late phases in a formalin test. In addition, 1 (50 and 100 mg/kg, ip) inhibited mechanical hyperalgesia, edema, and paw production of hyperalgesic cytokines (TNF-α and IL-1ß) induced by complete Freund's adjuvant. However, the local production of IL-10, an anti-inflammatory cytokine, was not altered by 1 (100 mg/kg, ip). Treatment with 1 produced a similar profile of antinociception in wild-type and IL-10-deficient mice. Mice treated with 1 did not show any motor performance alterations or apparent systemic toxicity. The results presented herein demonstrate that bergenin has consistent antinociceptive and anti-inflammatory properties, acting by the inhibition of IL-1ß and TNF-α production, and suggest its potential for the control of inflammatory pain.

Chemical composition and antimicrobial activity of essential oils of Ocimum canum Sims. and Ocimum selloi Benth.

This work describes the chemical composition and antimicrobial activity of the volatile oils of Ocimum canum and Ocimum selloi, both occurring in Jequié/BA, northeastern Brazil. The plants were collected in the winter/2005 and summer/2006, the oils extracted by steam distillation and further analyzed by GC-MS. A total of 30 and 31 compounds was identified from the oils of O. selloi and O. canum, respectively. It was observed that the oil content of O. canum showed variation during the seasons, while the oils of O. selloi did not. Methylchavicol and linalool were the main chemical components found in the aerial parts and leaves of O. canum. This finding permitted to characterize this specimen as a new chemotype of O. canum. Regarding the aerial parts of O. selloi, eugenol, 1,8-cineole, transcaryophyllene and linalool were identified as their major components. All extracted oils from the aerial parts showed biological activity against gram-positive cocci ­ Staphylococcus aureus ATCC 25923 ­ but only the O. canum one showed activity against gram-negative bacilli ­ Escherichia coli ATCC 25922.

Cytotoxic Activity of Tropane Alkaloides of Species of Erythroxylum.

Erythroxylaceae is a family composed of four genera, with Erythroxylum being the only one represented in the Neotropical region. Chemical studies indicate the presence of alkaloids, terpenes, flavonoids, and phenolic compounds as main compounds. The incorporation of cytotoxic activity assays of natural products using cell cultures assists in the selection of potential chemotherapeutic agents. In this work, we describe a revision of the cytotoxicity evaluation studies performed with extracts or pure substances obtained from Erythroxylum species through an integrative review. We found studies that evaluated the cytotoxic activity of 21 species of Erythroxylum against 45 different cell lines. The analysis of the chemical composition of these species shows that the metabolites present in each species influence their cytotoxic potential, especially the presence of disubstituted tropane alkaloid species with the highest cytotoxic potential. MTT and Sulforrodamine B assays were the main in vitro tests used for the evaluation of the cytotoxic activities. From the total species, less than 10% of the Erythroxylum species have already been evaluated for cytotoxic activity. Four of them showed high cytotoxic activity according to the criteria of the NCI plant screening program. Thus, this genus represents a potential source of natural products with antitumor activity.

Chemical constituents, antioxidant, anti-inflammatory and, antinociceptive activities of Trichilia ramalhoi.

Trichilia ramalhoi Rizz. is a species from Meliaceae family and its chemical composition and biological activities are still unknown. This work describes the chemical composition and biological activities of the organic extracts of this plant. Therefore, methanolic extract of stem barks and leaves were prepared and submitted to chromatographic procedures. Besides, T. ramalhoi extracts biological evaluation showed antioxidant, antinociceptive and, anti-inflammatory activities. Usual chromatographic procedures of the active extracts permitted to isolate methyl 5-O-caffeoylquinate, apocynin C, cinchonains Ia and Ib, besides ß-sitosterol, stigmasterol and lupeol. The identification of the isolates was based on 13C and 1H NMR (1 D and 2 D) spectroscopic data and mass spectrometry. Although the flavalignans cinchonains Ia and Ib were previously isolated from T. catigua, this is the first occurrence of apocynin C in the Meliaceae family.

Agathisflavone modulates astrocytic responses and increases the population of neurons in an in vitro model of traumatic brain injury.

Traumatic brain injury (TBI) is a critical health problem worldwide, with a high incidence rate and potentially severe long-term consequences. Depending on the level of mechanical stress, astrocytes react with complex morphological and functional changes known as reactive astrogliosis. In cases of severe tissue injury, astrocytes proliferate in the area immediately adjacent to the lesion to form the glial scar, which is a major barrier to neuronal regeneration in the central nervous system. The flavonoid agathisflavone has been shown to have neuroprotective, neurogenic, and immunomodulatory effects and could have beneficial effects in situations of TBI. In this study, we investigated the effects of agathisflavone on modulating the responses of astrocytes and neurons to injury, using the in vitro scratch wound model of TBI in primary cultures of rat cerebral cortex. In control conditions, the scratch wound induced an astroglial injury response, characterized by upregulation of glial fibrillary acidic protein (GFAP) and hypertrophy, together with the reduction in proportion of neurons within the lesion site. Treatment with agathisflavone (1 µM) decreased astroglial GFAP expression and hypertrophy and induced an increase in the number of neurons and neurite outgrowth into the lesion site. Agathisflavone also induced increased expression of the neurotrophic factors NGF and GDNF, which are associated with the neuroprotective profile of glial cells. These results demonstrate that in an in vitro model of TBI, the flavonoid agathisflavone modulates the astrocytic injury response and glial scar formation, stimulating neural recomposition.

Ryanodane diterpenes from two Erythroxylum species.

Ryanodane diterpenes, named 14-O-methyl-ryanodanol and ryanodanol, were isolated from ripe fruit of Erythroxylum passerinum. Compound 2 was also found in the leaves of this species, while 1 was obtained from the leaves of E. nummularia. Compound 1 showed insecticidal activity against Aedes aegypti larvae.

Radical scavenging, antioxidant and cytotoxic activity of Brazilian Caatinga plants.

Extracts of 32 plants from the Brazilian northeastern semi-arid region called Caatinga were evaluated through DPPH radical scavenging assay, beta-carotene bleaching, and brine shrimp lethality tests (BST). Among the extracts studied Byrsonima cf. gardneriana, Mascagnia coriacea, Cordia globosa, Diodia apiculata and Hypenia salzmannii showed the highest activities in DPPH radical scavenging test. In the beta-carotene bleaching test the highest activities were observed for Passiflora cincinnata, Chamaecrista repens, B. cf. gardneriana, Rollinia leptopetala, Serjania glabrata, Diospyros gaultheriifolia, C. globosa, Mimosa ophtalmocentra, M. coriacea and Lippia cf. microphylla. In contrast, R. leptopetala, Zornia cf. brasiliensis and Leonotis nepetifolia were the most active species in the BST.

Bergenin from Peltophorum dubium: Isolation, Characterization, and Antioxidant Activities in Non-Biological Systems and Erythrocytes.

BACKGROUND: Bergenin, a compound derived from gallic acid, is a secondary metabolite of the plant Peltophorum dubium (Spreng.) Taub. OBJECTIVE: In this study, we aimed to characterize the ability of bergenin to eliminate the radicals in non-biological systems. METHODS: We evaluated bergenin's ability to protect erythrocytes from oxidative damage in a biological system. We have elucidated bergenin structure using nuclear magnetic resonance, X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry. We then evaluated its antioxidant capacity in vitro against DPPH•, ABTS•+, hydroxyl radicals, and nitric oxide, and determined its ability to transfer electrons owing to its reduction potential and ability to chelate iron. We also evaluated its protective capacity against oxidative damage produced by AAPH in erythrocytes, its hemolytic properties, its ability to inhibit hemolysis, and its ability to maintain intracellular reduced glutathione homeostasis. RESULTS: Bergenin concentrations between 0.1 and 3mM significantly (p < 0.05) and dose dependently decreased formation of ABTS•+, DPPH•, nitrite ions, OH•, reduced formation ferricyanide, ferrozine-Fe2+complex, inhibited AAPH-induced oxidative hemolysis of erythrocytes, raised GSH levels in the presence of AAPH, inhibited AAPH-induced lipid peroxidation in erythrocytes. CONCLUSION: Bergenin may represent a novel alternative antioxidant, with potential applications in various industries, including drugs, cosmetics, and foods.

Two new isoflavonoids from Bowdichia virgilioides.

Two new isoflavonoids 7,8,4'-trimethoxyisoflavone and 7,8,4'-trimethoxyisoflavanone and calycosin (7,3'-hydroxy-4'-methoxyisoflavone) were isolated from the wood of the leguminous tree Bowdichia virgilioides by usual chromatographic procedures. Besides these compounds the pterocarpane (-)-maackianin, isoliquiritigenin (4,2',4'-trihydroxychalcone), and the hydrobenzylfurane derivative bowdenol were also obtained. The structures of these new compounds were determinated by MS and 1D and 2D NMR spectral analysis.