Evaluation of toxicity after one-months treatment with Bauhinia forficata decoction in streptozotocin-induced diabetic rats

Background: Previous experiments have shown that a decoction of Bauhinia forficata leaves reduces the changes in carbohydrate and protein metabolism that occur in rats with streptozotocin-induced diabetes. In the present investigation, the serum activities of enzymes known to be reliable toxicity markers were monitored in normal and streptozotocin-diabetic rats to discover whether the use of B. forficata decoction has toxic effects on liver, muscle or pancreas tissue or on renal microcirculation. Methods: An experimental group of normal and streptozotocin-diabetic rats received an aqueous decoction of fresh B. forficata leaves (150 g/L) by mouth for 33 days while a control group of normal and diabetic rats received water for the same length of time. The serum activity of the toxicity markers lactate dehydrogenase, creatine kinase, amylase, angiotensin-converting enzyme and bilirubin were assayed before receiving B. forficata decoction and on day 19 and 33 of treatment. Results: The toxicity markers in normal and diabetic rats were not altered by the diabetes itself nor by treatment with decoction. Whether or not they received B. forficata decoction the normal rats showed a significant increase in serum amylase activity during the experimental period while there was a tendency for the diabetic rats, both treated and untreated with decoction, to have lower serum amylase activities than the normal rats. Conclusions: Administration of an aqueous decoction of B. forficata is a potential treatment for diabetes and does not produce toxic effects measurable with the enzyme markers used in our study. © 2004 Pepato et al; licensee BioMed Central Ltd.

Effects of Ginkgo biloba on chemically-induced mammary tumors in rats receiving tamoxifen

Background: Ginkgo biloba extract (GbE) is used extensively by breast cancer patients undergoing treatment with Tamoxifen (TAM). Thus, the present study investigated the effects of GbE in female Sprague-Dawley (SD) rats bearing chemically-induced mammary tumors and receiving TAM.Methods: Animals bearing mammary tumors (≥1 cm in diameter) were divided into four groups: TAM [10 mg/kg, intragastrically (i.g.)], TAM plus GbE [50 and 100 mg/kg, intraperitoneally (i.p.)] or an untreated control group. After 4 weeks, the therapeutic efficacy of the different treatments was evaluated by measuring the tumor volume (cm3) and the proportions of each tumor that were alive, necrotic or degenerative (mm2). In addition, labeling indexes (LI%) were calculated for cell proliferation (PCNA LI%) and apoptosis (cleaved caspase-3 LI%), expression of estrogen receptor-alpha (ER-α) and p63 biomarkers.Results: Overall, the tumor volume and the PCNA LI% within live tumor areas were reduced by 83% and 99%, respectively, in all TAM-treated groups when compared to the untreated control group. GbE treatment (100 mg/kg) reduced the proportions of live (24.8%) and necrotic areas (2.9%) (p = 0.046 and p = 0.038, respectively) and significantly increased the proportion of degenerative areas (72.9%) (p = 0.004) in mammary tumors when compared to the group treated only with TAM. The expression of ER-α, p63 and cleaved caspase-3 in live tumor tissues was not modified by GbE treatment.Conclusions: Co-treatment with 100 mg/kg GbE presented a slightly beneficial effect on the therapeutic efficacy of TAM in female SD rats bearing mammary tumors. © 2013 Dias et al.; licensee BioMed Central Ltd.

Anticancer effects of geopropolis produced by stingless bees on canine osteosarcoma cells in vitro

Geopropolis is produced by indigenous stingless bees from the resinous material of plants, adding soil or clay. Its biological properties have not been investigated, such as propolis, and herein its cytotoxic action on canine osteosarcoma (OSA) cells was evaluated. OSA is a primary bone neoplasm diagnosed in dogs being an excellent model in vivo to study human OSA. spOS-2 primary cultures were isolated from the tumor of a dog with osteosarcoma and incubated with geopropolis, 70% ethanol (geopropolis solvent), and carboplatin after 6, 24, 48, and 72 hours. Cell viability was analyzed by the crystal violet method. Geopropolis was efficient against canine OSA cells in a dose- and time-dependent way, leading to a distinct morphology compared to control. Geopropolis cytotoxic action was exclusively due to its constituents since 70% ethanol (its solvent) had no effect on cell viability. Carboplatin had no effect on OSA cells. Geopropolis exerted a cytotoxic effect on canine osteosarcoma, and its introduction as a possible therapeutic agent in vivo could be investigated, providing a new contribution to OSA treatment. © 2013 Naiara Costa Cinegaglia et al.

Cinnamic acid is partially involved in propolis immunomodulatory action on human monocytes

Propolis is a beehive product used in traditional medicine due to its biological properties. It shows a complex chemical composition including phenolics, such as cinnamic acid (Ci). The mechanisms of action of propolis have been the subject of research recently; however, the involvement of Ci on propolis activity was not investigated on immune cells. Ci effects were evaluated on human monocytes, assessing the expression of Toll-like receptors (TLRs), HLA-DR, and CD80. Cytokine production (TNF-α and IL-10) and the fungicidal activity of monocytes were evaluated as well. Data showed that Ci downregulated TLR-2, HLA-DR, and CD80 and upregulated TLR-4 expression by human monocytes. High concentrations of Ci inhibited both TNF-α and IL-10 production, whereas the same concentrations induced a higher fungicidal activity against Candida albicans. TNF-α and IL-10 production was decreased by blocking TLR-4, while the fungicidal activity of monocytes was not affected by blocking TLRs. These results suggest that Ci modulated antigen receptors, cytokine production, and the fungicidal activity of human monocytes depending on concentration, and TLR-4 may be involved in its mechanism of action. Ci seemed to be partially involved in propolis activities. © 2013 Bruno José Conti et al.

Antimicrobial Brazilian propolis (EPP-AF) containing biocellulose membranes as promising biomaterial for skin wound healing

Among remarkable discoveries concerning propolis, such as antifungal, antiviral, and antioxidant activities, its anti-inflammatory, and mainly its antibacterial, properties deserve special attention when skin wound healing is concerned. Based on this and knowing the distinctive performance of bacterial (BC) membranes on wound healing, in this work it is proposed to demonstrate the potent antimicrobial activity and wound healing properties of a novel propolis containing biocellulose membrane. The obtained propolis/BC membrane was able to adsorb propolis not only on the surface, but also in its interstices demonstrated by scanning electron microscopy, X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, and thermogravidimetric assays. Additionally, the polyphenolic compounds determination and the prominent antibacterial activity in the membrane are demonstrated to be dose dependent, supporting the possibility of obtaining propolis/BC membranes at the desired concentrations, taking into consideration its application and its skin residence time. Finally, it could be suggested that propolis/BC membrane may favor tissue repair in less time and more effectively in contaminated wounds. © 2013 Hernane da Silva Barud et al.

Cytotoxicity of Brazilian plant extracts against oral microorganisms of interest to dentistry

Background: With the emergence of strains resistant to conventional antibiotics, it is important to carry studies using alternative methods to control these microorganisms causing important infections, such as the use of products of plant origin that has demonstrated effective antimicrobial activity besides biocompatibility. Therefore, this study aimed to evaluate the antimicrobial activity of plant extracts of Equisetum arvense L., Glycyrrhiza glabra L., Punica granatum L. and Stryphnodendron barbatimam Mart. against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Candida albicans, Candida tropicalis, and Candida glabrata, and to analyze the cytotoxicity of these extracts in cultured murine macrophages (RAW 264.7).Methods: Antimicrobial activity of plant extracts was evaluated by microdilution method based on Clinical and Laboratory Standards Institute (CLSI), M7-A6 and M27-A2 standards. The cytotoxicity of concentrations that eliminated the microorganisms was evaluated by MTT colorimetric method and by quantification of proinflammatory cytokines (IL-1β and TNF-α) using ELISA.Results: In determining the minimum microbicidal concentration, E. arvense L., P. granatum L., and S. barbatimam Mart. extracts at a concentration of 50 mg/mL and G. glabra L. extract at a concentration of 100 mg/mL, were effective against all microorganisms tested. Regarding cell viability, values were 48% for E. arvense L., 76% for P. granatum L, 86% for S. barbatimam Mart. and 79% for G. glabra L. at the same concentrations. About cytokine production after stimulation with the most effective concentrations of the extracts, there was a significant increase of IL-1β in macrophage cultures treated with S. barbatimam Mart. (3.98 pg/mL) and P. granatum L. (7.72 pg/mL) compared to control (2.20 pg/mL) and a significant decrease of TNF-α was observed in cultures treated with G. glabra L. (4.92 pg/mL), S. barbatimam Mart. (0.85 pg/mL), E. arvense L. (0.83 pg/mL), and P. granatum L. (0.00 pg/mL) when compared to control (41.96 pg/mL).Conclusions: All plant extracts were effective against the microorganisms tested. The G. glabra L. extract exhibited least cytotoxicity and the E. arvense L. extract was the most cytotoxic. © 2013 de Oliveira et al.; licensee BioMed Central Ltd.

Comparison of Brazilian plants used to treat gastritis on the oxidative burst of helicobacter pylori -stimulated neutrophil

Ten Brazilian medicinal plants used to treat gastritis and ulcers were carefully selected on the basis of ethnopharmacological importance and antiulcerogenic activity previously described. The antioxidant activity of the methanolic extracts was determined in analysis conditions that simulate a real biological activity on inhibition of the oxidative burst induced in neutrophils using Helicobacter pylori as activator, by a luminol-amplified chemiluminescence assay. The extracts, at low concentration (5 g/mL), exhibited a large variation in inhibitory effects of H. pylori-induced oxidative burst ranging from 48% inhibition to inactive, but all extracts, excluding Byrsonima intermedia, had inhibitory activity over 80% at the concentration of 100 g/mL. The total suppressive antioxidant capacity measured as the effective concentration, which represents the extract concentration producing 50% inhibition of the chemiluminescence induced by H. pylori, varies from 27.2 to 56.8 g/mL and was in the following order: Qualea parviflora > Qualea multiflora > Alchornea triplinervia > Qualea grandiflora > Anacardium humile > Davilla elliptica > Mouriri pusa > Byrsonima basiloba > Alchornea glandulosa > Byrsonima intermedia. The main groups of compounds in tested extracts are presented. Differences in the phytochemical profile, quantitatively and qualitatively, of these plants can explain and justify their protective effect on the gastric mucosa caused by the neutrophil-generated ROS that occurs when H. pylori displays its evasion mechanisms. © 2013 Cibele Bonacorsi et al.

Vellozia flavicans Mart. ex Schult. hydroalcoholic extract inhibits the neuromuscular blockade induced by Bothrops jararacussu venom

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Heteropterys tomentosa (A. Juss.) infusion counteracts Cyclosporin a side effects on the ventral prostate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Myrcia bella Leaf Extract Presents Hypoglycemic Activity via PI3k/Akt Insulin Signaling Pathway

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antifungal Activity of Decyl Gallate against Several Species of Pathogenic Fungi

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Flavones from Erythrina falcata are modulators of fear memory

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Essential oil of Melaleuca alternifolia for the treatment of oral candidiasis induced in an immunosuppressed mouse model

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The beneficial effect of equisetum giganteum L. against candida biofilm formation: new approaches to denture stomatitis

Equisetum giganteum L. (E. giganteum), Equisetaceae, commonly called giant horsetail, is an endemic plant of Central and South America and is used in traditional medicine as diuretic and hemostatic in urinary disorders and in inflammatory conditions among other applications. The chemical composition of the extract EtOH 70% of E. giganteum has shown a clear presence of phenolic compounds derived from caffeic and ferulic acids and flavonoid heterosides derived from quercitin and kaempferol, in addition to styrylpyrones. E. giganteum, mainly at the highest concentrations, showed antimicrobial activity against the relevant microorganisms tested: Escherichia coli, Staphylococcus aureus, and Candida albicans. It also demonstrated antiadherent activity on C. albicans biofilms in an experimental model that is similar to dentures. Moreover, all concentrations tested showed anti-inflammatory activity. The extract did not show cytotoxicity in contact with human cells. These properties might qualify E. giganteum extract to be a promising alternative for the topic treatment and prevention of oral candidiasis and denture stomatitis.

Evaluation of an Experimental Gel Containing Euclea natalensis: An In Vitro Study

Objective. To evaluate the effect of an experimental gel containing Euclea natalensis extract on dentin permeability. Methods. Thirty-six dentin discs, 1-mm-thick. The discs were prepared from the coronal dentin of extracted human third molars that were divided into 3 groups (n = 10). The dentin discs in each group were treated with the groups following experimental materials: (FG): 1.23% fluoride gel, pH 4.1; (EG): Euclea natalensis extract gel, pH 4.1; (CG): control gel, pH 4.1. The gels were applied to the occlusal slide of the dentin under the following conditions: after 37% phosphoric acid and before 6% citric acid. The hydraulic conductance (HC) of each condition was determined four times using a fluid flow apparatus (Flodec). The data were analyzed using Two-way ANOVA and Tukey's test (P < 0.05). Results. The greatest mean reduction in HC was produced in group EG dentin discs (61.2%; P < 0.05). Even after acid challenge with 6% citric acid the great reduction occurred in group EG (66.0%; P < 0.05) than other groups (CG-77.1%, FG-90.8%). Conclusion. E. natalensis gel not only reduced dentin permeability, but also resisted posttreatment citric acid challenge without changing its permeability. Further research has to confirm this promising result in the clinical situation.