Campomanesia adamantium O Berg. fruit, native to Brazil, can protect against oxidative stress and promote longevity.

Campomanesia adamantium O. Berg. is a fruit tree species native to the Brazilian Cerrado biome whose fruits are consumed raw by the population. The present study determined the chemical composition of the C. adamantium fruit pulp (FPCA) and investigated its in vitro antioxidant potential and its biological effects in a Caenorhabditis elegans model. The chemical profile obtained by LC-DAD-MS identified 27 compounds, including phenolic compounds, flavonoids, and organic carboxylic acids, in addition to antioxidant lipophilic pigments and ascorbic acid. The in vitro antioxidant activity was analysed by the radical scavenging method. In vivo, FPCA showed no acute reproductive or locomotor toxicity. It promoted protection against thermal and oxidative stress and increased the lifespan of C. elegans. It also upregulated the antioxidant enzymes superoxide dismutase and glutathione S-transferase and activated the transcription factor DAF-16. These results provide unprecedented in vitro and in vivo evidence for the potential functional use of FPCA in the prevention of oxidative stress and promotion of longevity.

In vitro evaluation of the cytotoxic and genotoxic effects of Al and Mn in ambient concentrations detected in groundwater intended for human consumption.

Environmental exposure to metals can induce cytotoxic and genotoxic effects in cells and affect the health of the exposed population. To investigate the effects of aluminum (Al) and manganese (Mn), we evaluated their cytogenotoxicity using peripheral blood mononuclear cells (PBMCs) exposed to these metals at previously quantified concentrations in groundwater intended for human consumption. The cell viability, membrane integrity, nuclear division index (NDI), oxidative stress, cell death, cell cycle, and DNA damage were analyzed in PBMCs exposed to Al (0.2, 0.6, and 0.8 mg/L) and Mn (0.1, 0.3, 1.0, and 1.5 for 48 h. We found that Al induced late apoptosis; decreased cell viability, NDI, membrane integrity; and increased DNA damage. However, no significant alterations in the early apoptosis, cell cycle, and reactive oxygen species levels were observed. In contrast, exposure to Mn altered all evaluated parameters related to cytogenotoxicity. Our data show that even concentrations allowed by the Brazilian legislation for Al and Mn in groundwater intended for human consumption cause cytotoxic and genotoxic effects in PBMCs. Therefore, in view of the results found, a comprehensive approach through in vivo investigations is needed to give robustness and validity to the results obtained, thus broadening the understanding of the impacts of metals on the health of environmentally exposed people.

Structural Characterization and Anticancer Activity of a New Anthraquinone from Senna velutina (Fabaceae).

In this study, a novel compound was isolated, identified, and its chemical structure was determined from the extract of the roots of Senna velutina. In addition, we sought to evaluate the anticancer potential of this molecule against melanoma and leukemic cell lines and identify the pathways of cell death involved. To this end, a novel anthraquinone was isolated from the barks of the roots of S. velutina, analyzed by HPLC-DAD, and its molecular structure was determined by nuclear magnetic resonance (NMR). Subsequently, their cytotoxic activity was evaluated by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) method against non-cancerous, melanoma, and leukemic cells. The migration of melanoma cells was evaluated by the scratch assay. The apoptosis process, caspase-3 activation, analysis of mitochondrial membrane potential, and measurement of ROS were evaluated by flow cytometry technique. In addition, the pharmacological cell death inhibitors NEC-1, RIP-1, BAPTA, Z-VAD, and Z-DEVD were used to confirm the related cell death mechanisms. With the results, it was possible to elucidate the novel compound characterized as 2'-OH-Torosaol I. In normal cells, the compound showed no cytotoxicity in PBMC but reduced the cell viability of all melanoma and leukemic cell lines evaluated. 2'-OH-Torosaol I inhibited chemotaxis of B16F10-Nex2, SK-Mel-19, SK-Mel-28 and SK-Mel-103. The cytotoxicity of the compound was induced by apoptosis via the intrinsic pathway with reduced mitochondrial membrane potential, increased levels of reactive oxygen species, and activation of caspase-3. In addition, the inhibitors demonstrated the involvement of necroptosis and Ca2+ in the death process and confirmed caspase-dependent apoptosis death as one of the main programmed cell death pathways induced by 2'-OH-Torosaol I. Taken together, the data characterize the novel anthraquinone 2'-OH-Torosaol I, demonstrating its anticancer activity and potential application in cancer therapy.

Chemical Components and Antioxidant Activity of Geotrigona sp. and Tetragonisca fiebrigi Stingless Bee Cerumen Reduce Juglone-Induced Oxidative Stress in Caenorhabditis elegans.

Cerumen is a bee product produced exclusively by stingless bees, resulting from a mixture of beeswax and plant resins. The antioxidant activity of bee products has been investigated since oxidative stress is associated with the onset and progression of several diseases that can lead to death. In this context, this study aimed to investigate the chemical composition and antioxidant activity of cerumen produced by the Geotrigona sp. and Tetragonisca fiebrigi stingless bees, in vitro and in vivo. The chemical characterization of cerumen extracts was performed by HPLC, GC, and ICP OES analyses. The in vitro antioxidant potential was evaluated by DPPH• and ABTS•+ free radical scavenging methods, and in human erythrocytes subjected to oxidative stress with AAPH. In vivo, the antioxidant potential was evaluated in Caenorhabditis elegans nematodes subjected to oxidative stress with juglone. Both cerumen extracts presented phenolic compounds, fatty acids, and metallic minerals in their chemical constitution. The cerumen extracts showed antioxidant activity by capturing free radicals, reducing lipid peroxidation in human erythrocytes, and reducing oxidative stress in C. elegans, observed by the increase in viability. The results obtained indicate that cerumen extracts from Geotrigona sp. and Tetragonisca fiebrigi stingless bees may be promising against oxidative stress and associated diseases.

Beneficial Effects of Bauhinia rufa Leaves on Oxidative Stress, Prevention, and Treatment of Obesity in High-Fat Diet-Fed C57BL/6 Mice.

Obesity is an epidemic disease worldwide, associated with oxidative stress and the development of several other diseases. Bauhinia rufa (Bong.) Steud. is a native Brazilian Cerrado medicinal plant popularly used for the treatment of obesity. In this context, we investigated the chemical composition of the methanolic extract of B. rufa leaves (MEBr) and evaluated the antioxidant activity and its impact on the prevention and treatment of obesity in mice fed a high-fat diet (HFD 60%). Additionally, the acute oral toxicity of MEBr was evaluated. In MEBr, 17 glycosylated compounds were identified, including myricetin, quercetin, kaempferol, coumaroyl, cyanoglucoside, and megastigmane. In vitro, MEBr showed antioxidant activity in different methods: DPPH•, ABTS•+, FRAP, iron-reducing power, inhibition of ß-carotene bleaching, and inhibition of DNA fragmentation. In human erythrocytes, MEBr increased the activities of antioxidant enzymes, superoxide dismutase, and catalase. Under oxidative stress, MEBr reduced oxidative hemolysis, and the malondialdehyde (MDA) levels generated in erythrocytes. Mice treated acutely with MEBr (2000 mg/kg) showed no signs of toxicity. During 90 days, the mice received water or MEBr simultaneously with HFD for induction of obesity. At this stage, MEBr was able to reduce the gain of subcutaneous white adipose tissue (WAT) and prevent the increase of MDA in the heart and brain. After 180 days of HFD for obesity induction, mice that received MEBr simultaneously with HFD (HFD-MEBr) in the last 60 days of treatment (120-180 days) showed a reduction of retroperitoneal and mesenteric WAT deposits and MDA levels in the heart, liver, kidney, and brain, compared to the HFD-Control group. These effects of MEBr were similar to mice treated with sibutramine (HFD-Sibutramine, 2 mg/kg). Combined, the results show that compounds from the leaves of B. rufa affect controlling oxidative stress and actions in the prevention and treatment of obesity. Thus, associated oxidative stress reduction and body composition modulation, in obese people, can contribute to the prevention of obesity-related comorbidities and improve quality of life.

Stingless Bee Propolis: New Insights for Anticancer Drugs.

Natural products are important sources of biomolecules possessing antitumor activity and can be used as anticancer drug prototypes. The rich biodiversity of tropical and subtropical regions of the world provides considerable bioprospecting potential, including the potential of propolis produced by stingless bee species. Investigations of the potential of these products are extremely important, not only for providing a scientific basis for their use as adjuvants for existing drug therapies but also as a source of new and potent anticancer drugs. In this context, this article organizes the main studies describing the anticancer potential of propolis from different species of stingless bees with an emphasis on the chemical compounds, mechanisms of action, and cell death profiles. These mechanisms include apoptotic events; modulation of BAX, BAD, BCL2-L1 (BCL-2 like 1), and BCL-2; depolarization of the mitochondrial membrane; increased caspase-3 activity; poly (ADP-ribose) polymerase (PARP) cleavage; and cell death induction by necroptosis via receptor interacting protein kinase 1 (RIPK1) activation. Additionally, the correlation between compounds with antioxidant and anti-inflammatory potential is demonstrated that help in the prevention of cancer development. In summary, we highlight the important antitumor potential of propolis from stingless bees, but further preclinical and clinical trials are needed to explore the selectivity, efficacy, and safety of propolis.

Rhynchophorus palmarum (Linnaeus, 1758) (Coleoptera: Curculionidae): Guarani-Kaiowá indigenous knowledge and pharmacological activities.

Zootherapy is a traditional secular practice among the Guarani-Kaiowá indigenous ethnic group living in Mato Grosso do Sul, Brazil. My people use the oil extracted from larvae of the snout beetle Rhynchophorus palmarum (Linnaeus, 1758) to treat and heal skin wounds and respiratory diseases. Based on this ethnopharmacological knowledge, the chemical composition and antioxidant, antimicrobial, and healing properties of R. palmarum larvae oil (RPLO) were investigated, as well as possible toxic effects, through in vitro and in vivo assays. The chemical composition of the RPLO was determined using gas chromatography coupled with mass spectrometry. The antioxidant activity of RPLO was investigated through the direct 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, and the antimicrobial activity was evaluated against Gram-positive and Gram-negative bacteria that are pathogenic to humans. The healing properties of RPLO were investigated by performing a cell migration assay using human lung fibroblasts (MRC-5), and the toxicity was analyzed, in vivo, using a Caenorhabditis elegans model and MRC-5 cells, in vitro. RPLO contains 52.2% saturated fatty acids and 47.4% unsaturated fatty acids, with palmitic acid (42.7%) and oleic acid (40%) representing its major components, respectively. RPLO possesses direct antioxidant activity, with a half-maximal inhibitory concentration (IC50) of 46.15 mg.ml-1. The antimicrobial activity of RPLO was not observed at a concentration of 1% (v/v). RPLO did not alter the viability of MRC-5 cells and did not exert toxic effects on C. elegans. Furthermore, MRC-5 cells incubated with 0.5% RPLO showed a higher rate of cell migration than that of the control group, supporting its healing properties. Taken together, RPLO possesses direct antioxidant activity and the potential to aid in the healing process and is not toxic toward in vitro and in vivo models, corroborating the safe use of the oil in traditional Guarani-Kaiowá medicine.

Application of the metabolomics approach to the discovery of active compounds from Brazilian trees against resistant human melanoma cells.

INTRODUCTION: The chemical diversity of plants plays an essential role in the development of new drugs. However, new bioactive compound identification and isolation are challenging due to the complexity and time-consuming nature of the traditional process. Recently, alternative strategies have become popular, such as the statistical approach to correlate compounds with biological activities, overcoming bottlenecks in bioactive natural product research. OBJECTIVE: We aimed to determine bioactive compounds against resistant human melanoma cells from leaves of Aspidosperma subincanum, Copaifera langsdorffii, Coussarea hydrangeifolia, Guarea guidonea and Tapirira guianensis, using a metabolomics approach. MATERIAL AND METHODS: The extracts and fractions were obtained by accelerated solvent extraction (ASE) and tested against resistant melanoma cells SK-MEL-28 and SK-MEL-103. Chemical analysis was performed by high-performance diode array detector tandem mass spectrometry (HPLC-DAD-MS/MS). Chemical and biological data were analysed through univariate and multivariate analysis. RESULTS: The species present high chemical diversity, including indole alkaloids, glycosylated flavonoids, galloylquinic acid derivatives, cinnamic acid derivatives, and terpenes. The ASE fractionation separated the compounds according to the physicochemical properties; only C. langsdorffii and T. guianensis extracts were active. Both results from the chemical profile and the biological assay were treated using a metabolomics approach to identify the contribution of different classes of secondary metabolites in the viability of human melanoma cells. The analyses showed the metabolites from C. langsdorffii and T. guianensis, such as polyphenols and terpenes, were the main compounds correlated with the biological response. CONCLUSION: These findings afford alternative pathways that are trustworthy and less time-consuming to identify new bioactive compounds against multidrug-resistant human melanoma cells.

The immunoregulatory function of polyphenols: implications in cancer immunity.

Polyphenols have demonstrated several potential biological activities, notably antitumoral activity dependent on immune function. In the present review, we describe studies that investigated antitumor immune responses influenced by polyphenols and the mechanisms by which polyphenols improve the immune response. We also discuss the limitations in related areas, especially unexplored areas of research, and next steps required to develop a therapeutic approach utilizing polyphenols in oncology.

Development of a novel anti-biofilm peptide derived from profilin of Spodoptera frugiperda.

Candida yeast infections are the fourth leading cause of death worldwide. Peptides with antimicrobial activity are a promising alternative treatment for such infections. Here, the antifungal activity of a new antimicrobial peptide-PEP-IA18-was evaluated against Candida species. PEP-IA18 was designed from the primary sequence of profilin, a protein from Spodoptera frugiperda, and displayed potent activity against Candida albicans and Candida tropicalis, showing a minimum inhibitory concentration (MIC) of 2.5 µM. Furthermore, the mechanism of action of PEP-IA18 involved interaction with the cell membrane (ergosterol complexation). Treatment at MIC and/or 10 × MIC significantly reduced biofilm formation and viability. PEP-IA18 showed low toxicity toward human fibroblasts and only revealed hemolytic activity at high concentrations. Thus, PEP-IA18 exhibited antifungal and anti-biofilm properties with potential applicability in the treatment of infections caused by Candida species.

Baru Pulp (Dipteryx alata Vogel): Fruit from the Brazilian Savanna Protects against Oxidative Stress and Increases the Life Expectancy of Caenorhabditis elegans via SOD-3 and DAF-16.

Fruits are sources of bioactive compounds that are responsible for several biological activities. Therefore, this study aimed to identify the chemical composition of the pulp of the Brazilian Savanna fruit Dipteryx alata; evaluate its toxic effects, influence on the life expectancy of the nematode Caenorhabditis elegans, and its antioxidant activities in vitro and in vivo; and describe the mechanisms involved. The chemical compounds identified include phenols, terpenes, fatty acid derivatives, vitamins, and a carboxylic acid. The in vitro antioxidant activity was demonstrated by radical scavenging methods. In vivo, the D. alata fruit pulp was not toxic and promoted resistance to oxidative stress in nematodes exposed to a chemical oxidizing agent. Furthermore, it promoted an increased life expectancy in wild-type nematodes and increased the expression of superoxide dismutase and the nuclear translocation of DAF-16. These results suggest that the beneficial effects identified are related to these two genes, which are involved in the regulation of metabolic activities, the control of oxidative stress, and the lifespan of C. elegans. These beneficial effects, which may be related to its chemical constituents, demonstrate its potential use as a functional and/or nutraceutical food.

Diversity, Chemical Constituents and Biological Activities of Endophytic Fungi Isolated from Schinus terebinthifolius Raddi.

Schinus terebinthifolius Raddi is a medicinal plant widely used for the treatment of various diseases. The secondary metabolites responsible for the pharmacological properties can be produced directly by the plant or by endophytic fungi. The objective of this study was to evaluate the diversity of endophytic fungi of different parts of S. terebinthifolius and to identify chemical compounds produced by endophytes and their antioxidant and antibacterial activities. For this, fruits, stem bark and roots were dried, ground and placed in fungal growth medium. The selected endophytes were grown and subjected to extraction with ethyl acetate. DPPH, FRAP, ß-carotene bleaching and antimicrobial assays were performed. The phylogenetic tree was elaborated, encompassing 15 different species. The fungal extracts showed hydroxybenzoic acids and 1-dodecanol as predominant compounds. All fungal extracts exhibited antioxidant activity. The fungal extracts exhibited bactericidal and bacteriostatic activities against Gram-positive and Gram-negative bacterial ATCC strains and against methicillin-resistant nosocomial bacteria. Among the 10 endophytic fungi evaluated, the extract of the fungus Ochrocladosporium elatum showed higher phenolic content and exhibited higher antioxidant and antibacterial activities in all tests. Together, the results increase the known diversity of S. terebinthifolius endophytic fungi, secondary metabolites produced and their antioxidant and antibacterial activities.

Acrocomia aculeata (Jacq.) Lodd. ex Mart. Leaves Increase SIRT1 Levels and Improve Stress Resistance.

Oxidative stress is a metabolic disorder linked with several chronic diseases, and this condition can be improved by natural antioxidants. The fruit pulp of the palm Acrocomia aculeata (Jacq.) Lodd. ex Mart. is widely used in the treatment of various illnesses, but as far as we know, there are no reports regarding the properties of its leaves. Thus, we aimed to evaluate the antioxidant activity of A. aculeata leaf extracts obtained with water (EA-Aa), ethanol (EE-Aa), and methanol (EM-Aa) solvents. The extracts were chemically characterized, and their antioxidant activity was assessed through the scavenging of the free radicals DPPH and ABTS. EE-Aa and EM-Aa showed the highest amounts of phenolic compounds and free radical scavenging activity. However, EA-Aa was more efficient to protect human erythrocytes against AAPH-induced hemolysis and lipid peroxidation. Thus, we further show the antioxidant effect of EA-Aa in preventing AAPH-induced protein oxidation, H2O2-induced DNA fragmentation, and ROS generation in Cos-7 cells. Increased levels of Sirt1, catalase, and activation of ERK and Nrf2 were observed in Cos-7 treated with EA-Aa. We also verify increased survival in nematodes C. elegans, when induced to the oxidative condition by Juglone. Therefore, our results showed a typical chemical composition of plants for all extracts, but the diversity of compounds presented in EA-Aa is involved in the lower toxicity and antioxidant properties provided to the macromolecules tested, proteins, DNA, and lipids. This protective effect also proven in Cos-7 and in C. elegans was probably due to the activation of the Sirt1/Nrf2 pathway. Altogether, the low toxicity and the antioxidant properties of EA-Aa showed in all the experimental models support its further use in the treatment of oxidative stress-related diseases.

Hydroethanolic stem bark extracts of Stryphnodendron adstringens impair M1 macrophages and promote M2 polarization.

ETHNOPHARMACOLOGICAL RELEVANCE: Stryphnodendron adstringens has been used by indigenous Brazilian people to treat wound, infections, inflammation and other conditions. AIM OF THE STUDY: This study aims to investigate the effect of S. adstringens on macrophage polarization. METHODS: To prepare the hydroethanolic extract of Stryphnodendron adstringens (HESA), fresh bark was exposed to maceration, filtered and subsequently lyophilized. The extract HESA were analyzed by LC-DAD-MS to identify their constituents. Bone marrow cells were obtained from male C57BL/6 mice. Then, the cells were polarized into M1 or M2 subsets in the presence or absence of HESA. The membrane expression of TLR2, CD206, CCR7, class II MHC, and CD86, the intracellular expression of iNOS and IL-6 and the supernatant expression of IL-6 were determined by flow cytometry. RESULTS: By LC-DAD-MS, twenty-four compounds could be detected from HESA and proanthocyanidins, flavan-3-ols, and chromones were identified. NO and iNOS were reduced in the HESA-treated cells. There was a reduction in IL6 in HESA-treated cells. The membrane expression of TLR2, CD206, CCR7, CD86, and class II MHC was reduced in HESA-treated cells. The densities of CD206 and IL-10 were found to be significantly increased in HESA-treated cells. CONCLUSION: This work is the first to demonstrate that S. adstringens can modulate the functional polarization of macrophages into the M2 profile and suppress costimulatory molecules in M1 macrophages. These results corroborate with the ethnopharmacology use of S. adstringens, contributing to its pharmacological validation in wound treatment and expanding the knowledge about immunoregulatory action of this specie.

Medicinal Plants from Brazilian Cerrado: Antioxidant and Anticancer Potential and Protection against Chemotherapy Toxicity.

The use of natural antioxidants in cancer therapy has increased: first, due to the potential of natural antioxidants to kill tumour cells and second, because of their capacity to protect healthy cells from the damage caused by chemotherapy. This review article discusses the antioxidant properties of extracts obtained from medicinal plants from the Brazilian Cerrado and the cell death profile induced by each of these extracts in malignant cells. Next, we describe the capacity of other medicinal plants from the Cerrado to protect against chemotherapy-induced cell toxicity. Finally, we focus on recent insights into the cell death profile induced by extracts from Cerrado plants and perspectives for future therapeutic approaches.

Ethanolic Extract of Senna velutina Roots: Chemical Composition, In Vitro and In Vivo Antitumor Effects, and B16F10-Nex2 Melanoma Cell Death Mechanisms.

Cutaneous melanoma is among the most aggressive types of cancer, and its rate of occurrence increases every year. Current pharmacological treatments for melanoma are not completely effective, requiring the identification of new drugs. As an alternative, plant-derived natural compounds are described as promising sources of new anticancer drugs. In this context, the objectives of this study were to identify the chemical composition of the ethanolic extract of Senna velutina roots (ESVR), to assess its in vitro and in vivo antitumor effects on melanoma cells, and to characterize its mechanisms of action. For these purposes, the chemical constituents were identified by liquid chromatography coupled to high-resolution mass spectrometry. The in vitro activity of the extract was assessed in the B16F10-Nex2 melanoma cell line using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and based on the apoptotic cell count; DNA fragmentation; necrostatin-1 inhibition; intracellular calcium, pan-caspase, and caspase-3 activation; reactive oxygen species (ROS) levels; and cell cycle arrest. The in vivo activity of the extract was assessed in models of tumor volume progression and pulmonary nodule formation in C57Bl/6 mice. The chemical composition results showed that ESVR contains flavonoid derivatives of the catechin, anthraquinone, and piceatannol groups. The extract reduced B16F10-Nex2 cell viability and promoted apoptotic cell death as well as caspase-3 activation, with increased intracellular calcium and ROS levels as well as cell cycle arrest at the sub-G0/G1 phase. In vivo, the tumor volume progression and pulmonary metastasis of ESVR-treated mice decreased over 50%. Combined, these results show that ESVR had in vitro and in vivo antitumor effects, predominantly by apoptosis, thus demonstrating its potential as a therapeutic agent in the treatment of melanoma and other types of cancer.

Microbiological quality, chemical profile as well as antioxidant and antidiabetic activities of Schinus terebinthifolius Raddi.

Schinus terebinthifolius Raddi, commonly known as Brazilian peppertree, is a plant species widely used in Brazilian traditional medicine for various purposes. The objective of this study was to assess the microbiological quality, safety, chemical profile as well as antioxidant and antidiabetic potentials of different parts of S. terebinthifolius. Microbiological analysis of the methanolic extracts of the roots (MESR), stem bark (MESB) and leaves (MESL) of S. terebinthifolius showed no microbial growth. The concentrations of phenolic compounds, phenolic acids and flavonoids were determined by spectrophotometry. The phenolic compounds of the MESL were identified by liquid chromatography coupled to a diode array detector and mass spectrometer (LC-DAD-MS). The antioxidant activities of the extracts were analyzed by 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radical (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical (ABTS+), fluorescence recovery after photobleaching (FRAP), reducing power, ß-carotene bleaching and malondialdehyde (MDA) assays in human erythrocytes. The antidiabetic properties of the extracts were demonstrated in vitro by their inhibition of the α-glucosidase enzyme and their anti-glycation activity via fructose and glyoxal. After showing no acute toxicity in vivo, MESL was able to lower postprandial glycemia after glucose overload in normoglycemic mice as well as the water and feed intake, liver weight, glycemia and serum levels of glycated hemoglobin, aspartate transaminase (AST) and alanine transaminase (ALT) in diabetic mice. Overall, S. terebinthifolius extracts showed microbiological safety along with antioxidant and antidiabetic activities, likely mediated by its chemical constituents, such as gallic acid, gallotannins and glycosylated flavonols.

Evaluation of In Vitro Antioxidant and Anticancer Properties of the Aqueous Extract from the Stem Bark of Stryphnodendron adstringens.

Stryphnodendron adstringens (Mart.) Coville (Fabaceae) is a tree species native to the Brazilian Cerrado commonly known as barbatimão. In traditional medicine, decoctions or infusions of the stem bark of this plant are used in the treatment of several diseases. The objective of this study was to analyze the chemical composition of Stryphnodendron adstringens aqueous extracts (SAAE) prepared from the stem bark to assess their antioxidant activity and anticancer effects as well as characterize cell death mechanisms against murine B16F10Nex-2 melanoma cells. From the SAAE, gallic acid, gallocatechin, epigallocatechin, dimeric and trimeric proanthocyanidins mainly composed of prodelphinidin units and the isomeric chromones C-hexosyl- and O-pentosyl-5,7-dihydroxychromone were identified. The SAAE showed antioxidant activity through direct free-radical scavenging as well as through oxidative hemolysis and lipid peroxidation inhibition in human erythrocytes. Furthermore, SAAE promoted apoptosis-induced cell death in melanoma cells by increasing intracellular reactive oxygen species (ROS) levels, inducing mitochondrial membrane potential dysfunction and activating caspase-3. Together, these data show the antioxidant and anticancer effects of Stryphnodendron adstringens. These results open new perspectives for studies against other tumor cell lines and in vivo models as well as for the identification and isolation of the chemical constituents responsible for these effects.

Guazuma ulmifolia Lam. Decreases Oxidative Stress in Blood Cells and Prevents Doxorubicin-Induced Cardiotoxicity.

Doxorubicin (DOX) is an efficient chemotherapeutic agent, but its clinical application is limited by its cardiotoxicity associated with increased oxidative stress. Thus, the combination of DOX and antioxidants has been encouraged. In this study, we evaluated (I) the chemical composition and antioxidant capacity of aqueous extracts from Guazuma ulmifolia stem bark (GUEsb) and leaves (GUEl) in 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, 2,2'-azobis(2-amidinopropane) dihydrochloride- (AAPH-) or DOX-induced lipid peroxidation inhibition in human blood cells, and intracellular reactive oxygen species (ROS) quantification using the fluorescent probe dichloro-dihydro-fluorescein diacetate (DCFH-DA) in K562 erythroleukemia cells incubated with GUEsb and stimulated with hydrogen peroxide; (II) the viability of K562 cells and human leukocytes treated with GUEsb in the absence or presence of DOX using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; (III) the acute toxicity of GUEsb; and (IV) the cardioprotective effect of GUEsb in C57Bl/6 mice treated with DOX. The chemical composition indicated the presence of flavan-3-ol derivatives and condensed tannins in GUEsb and glycosylated flavonoids in GUEl. GUEsb and GUEl showed free-radical scavenging antioxidant activity, antihemolytic activity, and AAPH- as well as DOX-induced malondialdehyde content reduction in human erythrocytes. Based on its higher antioxidant potential, GUEsb was selected and subsequently showed intracellular ROS reduction without impairing the chemotherapeutic activity of DOX in K562 cells or inducing leukocyte cell death, but protected them against DOX-induced cell death. Yet, GUEsb did not show in vivo acute toxicity, and it prevented MDA generation in the cardiac tissue of DOX-treated mice, thus demonstrating its cardioprotective effect. Taken together, the results show that GUEsb and GUEl are natural alternatives to treat diseases associated with oxidative stress and that, in particular, GUEsb may play an adjuvant role in DOX chemotherapy.

Physicochemical Characterization, Microbiological Quality and Safety, and Pharmacological Potential of Hancornia speciosa Gomes.

Hancornia speciosa Gomes is a fruit tree, commonly known as the mangaba tree, which is widespread throughout Brazil. The leaves of this plant are used in traditional medicine for medicinal purposes. Thus, the objective of this study was to perform a physicochemical characterization, identify the lipophilic antioxidants and fatty acids, and determine the microbiological quality and safety of H. speciosa leaves. In addition, the antioxidant, antimutagenic, and inhibitory activities of the ethanolic extract of H. speciosa leaves (EEHS) against enzymes related to neurodegenerative diseases, inflammation, obesity, and diabetes were investigated. Furthermore, this study aimed at assessing the in vivo effects of the EEHS on the glycemia of normoglycemic and diabetic Wistar rats. Physicochemical characterization was performed by colorimetry and gas-liquid chromatography with flame ionization detection (GC-FID). The total number of colonies of aerobic mesophiles, molds, and yeasts was determined. The total coliforms and Escherichia coli were counted using the SimPlates kit, and sulphite-reducing Clostridium spores were quantified using the sulphite-polymyxin-sulfadiazine agar method. Salmonella spp. were detected using the 1-2 Test. The antioxidant activity of the EEHS was measured by its inhibition of 2,2'-azobis(2-amidinopropane) dihydrochloride- (AAPH-) induced oxidative hemolysis of human erythrocytes. The antimutagenic activity was determined using the Ames test. The acetylcholinesterase, butyrylcholinesterase, tyrosinase, hyaluronidase, lipase, α-amylase, and α-glycosidase enzyme-inhibiting activities were assessed and compared with commercial controls. The in vivo effects of the EEHS were assessed using the oral glucose tolerance test in normoglycemic Wistar rats and measuring the blood glucose levels in diabetic rats. The results demonstrated physical-chemical parameters of microbiological quality and safety in the leaves of H. speciosa, as well as antioxidant and antimutagenic activities and inhibition of enzymes related to neurodegenerative diseases, inflammation, obesity, and diabetes. In in vivo assays, it was shown that the normoglycemic rats challenged with glucose overload show significantly decreased blood glucose levels when treated with the EEHS. Taken together, the results ensure the microbiological quality and safety as well as showing the contents of carotenoids and polyunsaturated fatty acids of H. speciosa leaves. Additionally, the antioxidant, antimutagenic, anti-inflammatory, anti-Alzheimer's disease, anti-Parkinson's disease, antiobesity, and antihyperglycemic activities of the EEHS were demonstrated.