New Therapeutic Strategies for Obesity and Its Metabolic Sequelae: Brazilian Cerrado as a Unique Biome.

Brazil has several important biomes holding impressive fauna and flora biodiversity. Cerrado being one of the richest ones and a significant area in the search for new plant-based products, such as foods, cosmetics, and medicines. The therapeutic potential of Cerrado plants has been described by several studies associating ethnopharmacological knowledge with phytochemical compounds and therapeutic effects. Based on this wide range of options, the Brazilian population has been using these medicinal plants (MP) for centuries for the treatment of various health conditions. Among these, we highlight metabolic diseases, namely obesity and its metabolic alterations from metabolic syndrome to later stages such as type 2 diabetes (T2D). Several studies have shown that adipose tissue (AT) dysfunction leads to proinflammatory cytokine secretion and impaired free fatty acid (FFA) oxidation and oxidative status, creating the basis for insulin resistance and glucose dysmetabolism. In this scenario, the great Brazilian biodiversity and a wide variety of phytochemical compounds make it an important candidate for the identification of pharmacological strategies for the treatment of these conditions. This review aimed to analyze and summarize the current literature on plants from the Brazilian Cerrado that have therapeutic activity against obesity and its metabolic conditions, reducing inflammation and oxidative stress.

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.

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.

Spondias purpurea L. Bark Extract Protects against Oxidative Stress and Reduces Hypercholesterolemia in Mice Fed High-Fat Diet.

Oxidative stress plays a key role in the initiation and progression of metabolic diseases, including obesity. Preventing the accumulation of reactive oxygen species and oxidative damage to macromolecules is a beneficial strategy for reducing comorbidities associated with obesity. Fruits from the Spondias genus are known for their antioxidant activity, but they are not available year-round due to their seasonality. In this context, we investigated the antioxidant activity and identified the chemical constituents of the aqueous extract of the stem bark of Spondias purpurea L. (EBSp). Additionally, we evaluated the effect of EBSp consumption on metabolic parameters in mice with obesity induced by a high-fat diet. Chemical analyses revealed 19 annotated compounds from EBSp, including flavan-3-ols, proanthocyanidins, methoxylated coumarin, and gallic and ellagic acids, besides other phenolic compounds. In vitro, EBSp showed antioxidant activity through the scavenging of the free radicals and the protection of macromolecules against oxidative damage. Cellular assays revealed that EBSp reduced the levels of malondialdehyde produced by erythrocytes exposed to the oxidizing agent AAPH. Flow cytometry studies showed that EBSp reduced reactive oxygen species levels in human peripheral blood mononuclear cells treated with hydrogen peroxide. Obese mice treated with EBSp (400 mg.kg-1) for 60 days showed reduced levels of malondialdehyde in the heart, liver, kidneys, and nervous system. The total cholesterol levels in mice treated with EBSp reached levels similar to those after treatment with the drug simvastatin. Together, the results show that the combination of the different phenolic compounds in S. purpurea L. bark promotes antioxidant effects in vitro and in vivo, resulting in cytoprotection in the context of oxidative stress associated with obesity and a reduction in hypercholesterolemia. From a clinical perspective, the reduction in oxidative stress in obese individuals contributes to the reduction in the emergence of comorbidities associated with this metabolic syndrome.

Hypoglycaemic and Antioxidant Properties of Acrocomia aculeata (Jacq.) Lodd Ex Mart. Extract Are Associated with Better Vascular Function of Type 2 Diabetic Rats.

Oxidative stress is involved in the metabolic dysregulation of type 2 diabetes (DM2). Acrocomia aculeata (Aa) fruit pulp has been described for the treatment of several diseases, and recently we have proved that its leaves have phenolic compounds with a marked antioxidant effect. We aimed to assess whether they can improve metabolic, redox and vascular functions in DM2. Control Wistar (W-Ctrl) and non-obese type 2 diabetic Goto-Kakizaki (GK-Ctrl) rats were treated for 30 days with 200 mg.kg-1 aqueous extract of Aa (EA-Aa) (Wistar, W-EA-Aa/GK, GK-EA-Aa). EA-Aa was able to reduce fasting glycaemia and triglycerides of GK-EA-Aa by improving proteins related to glucose and lipid metabolism, such as GLUT-4, PPARγ, AMPK, and IR, when compared to GK-Ctrl. It also improved viability of 3T3-L1 pre-adipocytes exposed by H2O2. EA-Aa also increased the levels of catalase in the aorta and kidney, reduced oxidative stress and increased relaxation of the aorta in GK-treated rats in relation to GK-Ctrl, in addition to the protective effect against oxidative stress in HMVec-D cells. We proved the direct antioxidant potential of the chemical compounds of EA-Aa, the increase in antioxidant defences in a tissue-specific manner and hypoglycaemic properties, improving vascular function in type 2 diabetes. EA-Aa and its constituents may have a therapeutic potential for the treatment of DM2 complications.

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.

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.

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.

Investigation of the antioxidant and hypoglycemiant properties of Alibertia edulis (L.C. Rich.) A.C. Rich. leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Alibertia edulis (L.C. Rich.) A.C. Rich is a vegetable species used in Brazilian folk medicine due to it is putative hypoglycemiant effect but has never been pharmacologically investigated. It is popularly used for the control of diabetes, especially in the state of Mato Grosso, Brazil. Following confirmation of the antioxidant activity of A. edulis by Aquino et al. (2017), the aim of this study was to evaluate the effects of leaves of A. edulis aqueous extract (AEAE) on some biochemical parameters in mice fed a high-fat fed. MATERIAL AND METHODS: Leaves of A. edulis were air-dried in an oven at 40 °C for 10 days and ground into a fine powder by mechanical milling. The AEAE was prepared by decoction (1:10 w/v) at 97 °C for 15 min, and later filtered and lyophilized. Preliminary phytochemical analysis of the AEAE has been already indetified the presence of caffeic acid, quercetin 3-rhamnosyl-(1 â†’ 6)-galactoside and iridois ioxide, ferulic acid and rutin in decocted leaves (Aquino et al., 2017). In one experiment, the acute oral toxicity AEAE was evaluated at 2,000 mg/kg of body weight. The animals were observed periodically for 14 days. In second experiment, the animals were divided into four groups (n = 5): Control, AEAE 200, AEAE 400 mg/kg and positive control (Metformin 100 mg/kg). In a third experiment, animals were divided into: Control RC (standard diet) (n = 24) and Control HFF (high-fat fed) (n = 24) groups for induction of glucose intolerance. After eight weeks, they were further subdivided into six groups (n = 8 each) RC or HFF with or without AEAE at doses of 200 and 400 mg/kg (2-wk) treatments to assess glucose tolerance. Plasma indicators of glucose tolerance and liver damage, skeletal muscle expression of antioxidant enzymes, and expression of the antioxidant proteins of superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and phosphorylated IKK were determined. RESULTS: The HF-fed animals developed glucose intolerance which the AEAE failed to revert. Meanwhile, the AEAE treatment did lower the glucose levels in the normolipidic cohorts by virtue of its antioxidant property. It was also observed that the treatment with the AEAE reduced food intake negatively interfering weight accretion. Beyond that, the treatment with AEAE interfered in the SOD and catalase expression and inhibited phosphorylation of IKK thus suggesting that the observed hypoglycemiant power may be related to its known antioxidant potential. No sings of toxicity or hemolysis were detectaed at indicating that, at the concentrations evaluated, the extract was not toxic to normal cells. CONCLUSION: The AEAE showed a hypoglycemiant effect in the normolipidic mice that received the control diet, but not in those that were made glucose-intolerant by consuming a high-fat fed. The extract also exhibited substantial protection against hemolysis and oxidative stress. Moreover, no signs of toxicity were evident at 2000 mg/kg of body weight.

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.

Chemical Composition, Antimicrobial Activity, and Antioxidant Activity of Ocotea minarum (Nees & Mart.) Mez.

Ocotea minarum is a native plant from Brazil, popularly known as "canelinha" or "canela vassoura." The objective of this study was to investigate the chemical composition of the extracts of the bark and the leaves of O. minarum and to evaluate its antimicrobial and antioxidant activities. The phenolic compounds, flavonoids and tanins, were quantified with the reagents Folin-Ciocalteu, aluminium chloride, and vanillin. The chemical profile was performed by HPLC-DAD. The minimum inhibitory concentration was evaluated by the microdilution in a broth method. The antioxidant activity was measured by the capture of free radicals 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid). In addition, protection against oxidative hemolysis and generation of malondialdehyde were evaluated in human erythrocytes. The composition of the extracts included the caffeic acid, p-coumaric acid, and rosmarinic acid, besides the flavonoids quercetin and luteolin. The EEL showed bacteriostatic action of 1000 µg/mL for all evaluated Salmonella Typhimurium, Salmonella Enteritidis, Pseudomonas aeruginosa, and Proteus mirabilis, and the EHEB had a moderate antifungal action against Candida krusei and Cryptococcus gattii (250 µg/mL). IC50 values of 8.19 (EEL) and 4.51 µg/mL (EEB) in the assay with DPPH and 6.25 (EEL) and 2.87 µg/mL (EEB) in the assay with ABTS were obtained. Up to the 3rd hour of oxidative hemolysis testing induced by AAPH, the EEB and EEL had a protective action, reducing the malondialdehyde. In conclusion, the data indicate that the O. minarum extracts can be evaluated as bioactive supplies for the development of new drugs for the prevention and treatment of diseases related to oxidative stress and microbial infections.

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.

Antioxidant, antihyperglycemic, and antidiabetic activity of Apis mellifera bee tea.

Diabetes has emerged as one of the largest global epidemics; it is estimated that by 2035, there will be 592 million diabetic people in the world. Brazilian biodiversity and the knowledge of traditional peoples have contributed to the treatment of several diseases, including diabetes. Apis mellifera bee tea is used by indigenous Brazilians to treat diabetes, and this traditional knowledge needs to be recorded and studied.The objective of this study was to record the use and to evaluate the antioxidant, antihyperglycemic, and antidiabetic activity of Apis mellifera bee tea, which is used by the Guarani and Kaiowá indigenous people for the treatment of diabetes. Semi-structured interviews were performed with Guarani and Kaiowá ethnic indigenous people from the State of Mato Grosso do Sul, Brazil, seeking to identify the animal species used for medicinal purposes. For the experimental procedures, tea prepared with macerated Apis mellifera bees was used. In vitro assays were performed to evaluate antioxidant activity; direct free radical scavenging, protection against oxidative hemolysis, lipid peroxidation were evaluated in human erythrocytes and potential in inhibiting the formation of advanced glycation end products (AGEs). In vivo, normoglycemic Swiss male mice treated with Apis mellifera tea (AmT) were subjected to the oral glucose tolerance test and compared with control and metformin-treated groups. Diet-induced diabetic mice were treated for 21 days with AmT and evaluated for glycemia and malondialdehyde levels in the blood, liver, nervous system, and eyes. During interviews, the indigenous people described the use of Apis mellifera bee tea for the treatment of diabetes. In in vitro assays, AmT showed direct antioxidant activity and reduced oxidative hemolysis and malondialdehyde generation in human erythrocytes. The AmT inhibited the formation of AGEs by albumin-fructose pathways and methylglyoxal products. In vivo, after oral glucose overload, normoglycemic mice treated with AmT had reduced hyperglycemia at all times evaluated up to 180 min. AmT also reduced hyperglycemia and malondialdehyde levels in the blood, liver, nervous system, and eyes of diabetic mice to similar levels as those in metformin-treated mice and normoglycemic controls. In summary, Apis mellifera bee tea showed antioxidant, antihyperglycemic, and antidiabetic activity, which provides support for the therapeutic application of Guarani and Kaiowá indigenous knowledge.

The Chemical Composition and Metabolic Effects of Attalea phalerata Nut Oil in Hyperlipidemic Rats Induced by a High-Fructose Diet.

The fatty acids found in nuts are important regulators of the metabolism. These acids are frequently associated with a reduction of serum cholesterol and body fat and a lower risk of developing cardiovascular disease. In this context, the aim of this study was to identify and quantify the nut oil fatty acids from Attalea phalerata and investigate their metabolic effects in rats with hyperlipidemia induced by a diet rich in fructose. Oleic and lauric acids were the major compounds found in the A. phalerata nut oil (APNO). Hyperlipidemic rats treated with APNO showed a reduction in the total serum cholesterol similar to those treated with simvastatin, an increased body temperature by 1 °C, and a reduction in the body weight gain and mesenteric depot of white adipose tissue compared to the hyperlipidemic controls rats. There was an increase in the relative liver weight of rats treated with APNO, without, however, any change in the serum markers of hepatic toxicity. In addition, there was an increase in the moisture and lipid content of the feces of the rats treated with APNO compared to the controls. Together, these results suggest that APNO has potential use in health foods and nutritional supplements to control hypercholesterolemia and obesity.