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.

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.

Diversity of cultivable fungal endophytes in Paullinia cupana (Mart.) Ducke and bioactivity of their secondary metabolites.

Paullinia cupana is associated with a diverse community of pathogenic and endophytic microorganisms. We isolated and identified endophytic fungal communities from the roots and seeds of P. cupana genotypes susceptible and tolerant to anthracnose that grow in two sites of the Brazilian Amazonia forest. We assessed the antibacterial, antitumor and genotoxic activity in vitro of compounds isolated from the strains Trichoderma asperellum (1BDA) and Diaporthe phaseolorum (8S). In concert, we identified eight fungal species not previously reported as endophytes; some fungal species capable of inhibiting pathogen growth; and the production of antibiotics and compounds with bacteriostatic activity against Pseudomonas aeruginosa in both susceptible and multiresistant host strains. The plant genotype, geographic location and specially the organ influenced the composition of P. cupana endophytic fungal community. Together, our findings identify important functional roles of endophytic species found within the microbiome of P. cupana. This hypothesis requires experimental validation to propose management of this microbiome with the objective of promoting plant growth and protection.

Dietary supplementation with camu-camu and continuous exercises in the treatment of obesity / Suplementação dietética com camu-camu e exercícios contínuos no tratamento da obesidade

ABSTRACT Objective The goal of this study were to investigate the effects of continuous exercise with/or without the ingestion the Camu-camu pulp in a rat model of obesity. Methods Neonate male Wistar rats, receiving monosodium glutamate, subcutaneously were separated into foour groups: sedentary group S (no treatment), exercise group E (continuous swimming training), Camu-camu group C (25mL of pulp of Camu-camu/day) and exercise and Camu-camu group EC (25mL of pulp of Camu-camu/day, continuous swimming). After 12 weeks, the animals were received euthanasia. Results The exercise program was conducted for five days for 12 weeks and the effects of supplementation with or without Camu-camu in obese rats were analyzed, showing that the relative levels of the variables cholesterol, triglycerides, glucose, High Density Lipoprotein and Low Density Lipoprotein and in all groups there was a significant reduction (.<0.001), except for the control group. Body weight and feed intake, epididymal and visceral fat deposits were not significantly different between the means of groups C and E, but these groups showed a significant difference when compared to the EC group (.<0.001). Conclusion The results demonstrate the effectiveness of continuous exercise and diet supplemented with Camu-camu fruit pulp to control obesity.

RESUMO Objetivo O objetivo deste estudo foi investigar os efeitos do exercício contínuo, com ou sem a ingestão da polpa de camu-camu, em um modelo de ratos obesos. Métodos Ratos machos neonatos Wistar receberam glutamato monossódico subcutaneamente e foram separados em três grupos. grupo de exercício E (treinamento de natação contínuo); grupo exercitado e suplementado com camu-camu - EC (natação contínua e administração de camu-camu); e grupo sedentário S (sem tratamento), como controle. Concluído o experimento, os animais sofreram eutanásia. Resultados O experimento teve a duração de doze semanas. O protocolo de exercício de natação (120min) e a ingestão da suplementação com camu-camu de polpa (25mL) tiveram a mesma duração e foram feitas simultaneamente cinco vezes por semana. Os resultados apontaram redução significativa (p<0,001) dos níveis relativos das variáveis colesterol, triglicérides, glicose, High Density Lipoprotein e Low Density Lipoprotein nos dois primeiros grupos, quando comparados ao grupo controle. Quanto a peso corporal e consumo de ração, depósitos de gordura epididimal e visceral, não houve diferença significativa entre as médias dos grupos C e E - porém, estes grupos apresentaram diferença significativa quando comparados ao grupo suplementado com camu-camu (p<0,001). Conclusão Os resultados demonstraram a efetividade do exercício contínuo e da dieta suplementada com a polpa de camu-camu para o controle da obesidade.

Antioxidant and Protective Effects of Schinus terebinthifolius Raddi Against Doxorubicin-Induced Toxicity.

Doxorubicin is an anticancer drug whose toxic effects on non-cancer cells are associated with increased oxidative stress. This study investigated the chemical composition, antioxidant activity of the methanolic extract of Schinus terebinthifolius Raddi leaves (MESL) as well as effects against doxorubicin-induced toxicity in human erythrocytes, K562 human erythroleukemia cells, and mouse hearts. The chemical composition indicated the presence of phenolic compounds, flavonoids, tannins, and ascorbic acid. MESL showed antioxidant activity by scavenging free radicals and inhibiting hemolysis and lipid peroxidation in human erythrocytes incubated with an oxidizing agent, and was able to increase the enzymatic activity of superoxide dismutase and glutathione peroxidase in human erythrocytes, without influencing the activity of enzyme catalase. The increase of oxidative hemolysis and malondialdehyde levels in erythrocytes incubated with doxorubicin was reduced by treatment with MESL. The cytotoxic activity of doxorubicin in erythroleukemia cells treated with MESL was unmodified. Additionally, the extract protected mice against the doxorubicin-induced cardiotoxicity. In conclusion, the MESL exhibits antioxidant activity, reducing doxorubicin-induced oxidative stress without changing the anticancer action of the drug, and protects against doxorubicin-induced cardiotoxicity. Hence, these findings suggest that these effects are via anti-oxidative by inhibiting free radicals, decreased oxidative stress, and increased antioxidant enzyme activity.

Extract from Eugenia punicifolia is an antioxidant and inhibits enzymes related to metabolic syndrome.

The present study aimed to investigate in vitro biological activities of extract of Eugenia punicifolia leaves (EEP), emphasizing the inhibitory activity of enzymes related to metabolic syndrome and its antioxidant effects. The antioxidant activity was analyzed by free radicals scavengers in vitro assays: DPPH·, ABTS(·+), O2(·−), and NO· and a cell-based assay. EEP were tested in inhibitory colorimetric assays using α-amylase, α-glucosidase, xanthine oxidase, and pancreatic lipase enzymes. The EEP exhibited activity in ABTS(·+), DPPH·, and O2(·−) scavenger (IC50 = 10.5 ± 1.2, 28.84 ± 0.54, and 38.12 ± 2.6 µg/mL), respectively. EEP did not show cytotoxic effects, and it showed antioxidant activity in cells in a concentration-dependent manner. EEP exhibited inhibition of α-amylase, α-glucosidase, and xanthine oxidase activities in vitro assays (IC50 = 122.8 ± 6.3; 2.9 ± 0.1; 23.5 ± 2.6), respectively; however, EEP did not inhibit the lipase activity. The findings supported that extract of E. punicifolia leaves is a natural antioxidant and inhibitor of enzymes, such as α-amylase, α-glucosidase, and xanthine oxidase, which can result in a reduction in the carbohydrate absorption rate and decrease of risks factors of cardiovascular disease, thereby providing a novel dietary opportunity for the prevention of metabolic syndrome.