The effect of the dibenzylbutyrolactolic lignan (-)-cubebin on doxorubicin mutagenicity and recombinogenicity in wing somatic cells of Drosophila melanogaster

The dibenzylbutyrolactolic lignan (-)-cubebin was isolated from dry seeds of Piper cubeba L (Piperaceae). (-)-Cubebin possesses anti-inflammatory, analgesic and antimicrobial activities. Doxorubicin (DXR) is a topoisomerase-interactive agent that may induce single- and double-strand breaks, intercalate into the DNA and generate oxygen free radicals. Here, we examine the mutagenicity and recombinogenicity of different concentrations of (-)-cubebin alone or in combination with DXR using standard (ST) and high bioactivation (HB) crosses of the wing Somatic Mutation And Recombination Test in Drosophila melanogaster. The results from both crosses were rather similar. (-)-Cubebin alone did not induce mutation or recombination. At lower concentrations, (-)-cubebin statistically reduced the frequencies of DXR-induced mutant spots. At higher concentrations, however, (-)-cubebin was found to potentiate the effects of DXR, leading to either an increase in the production of mutant spots or a reduction, due to toxicity. These results suggest that depending on the concentration, (-)-cubebin may interact with the enzymatic system that catalyzes the metabolic detoxification of DXR, inhibiting the activity of mitochondria! complex 1 and thereby scavenging free radicals. Recombination was found to be the major effect of the treatments with DXR alone. The combined treatments reduced DXR mutagenicity but did not affect DXR recombinogenicity. (C) 2011 Elsevier Ltd. All rights reserved.

Mutagenicity and Antimutagenicity of Baccharis dracunculifolia Extract in Chromosomal Aberration Assays in Chinese Hamster Ovary Cells

Baccharis dracunculifolia De Candole (Asteraceae), a native plant from the Brazilian ""cerrado"", is widely used in folk medicine as an anti-inflammatory agent and for the treatment of gastrointestinal diseases. B. dracunculifolia has been described as the most important plant source of propolis in southeastern Brazil, which is called green propolis due to its color. The aim of the present study was to evaluate the mutagenic and antimutagenic effects of the ethyl acetate extract of B. dracunculifolia leaves (Bd-EAE) on Chinese hamster ovary cells. On one hand, the results showed a significant increase in the frequencies of chromosome aberrations at the highest Bd-EAE concentration tested (100 mu g/mL). On the other hand, the lowest Bd-EAE concentration tested (12.5 mu/mL) significantly reduced the chromosome damage induced by the chemotherapeutic agent doxorubicin. The present results indicate that Bd-EAE has the characteristics of a so-called Janus compound, that is, Bd-EAE is mutagenic at higher concentrations, whereas it displays a chemopreventive effect on doxorubicin-induced mutagenicity at lower concentrations. The constituents of B. dracunculifolia responsible for its mutagenic and antimutagenic effects are probably flavonoids and phenylpropanoids, since these compounds can act either as pro-oxidants or as free radical scavengers depending on their concentration.

Antileishmanial, antimalarial and antimicrobial activities of the extract and isolated compounds from Austroplenckia populnea (Celastraceae)

Austroplenckia populnea (Celastraceae), known as ""marmelinho do campo"", is used in Brazilian folk medicine as antimicrobial, anti-inflammatory, and antitumoural agent. The aim of the present work was to evaluate the antimicrobial. antileishmanial and antimalarial activities of the crude hydroalcoholic extract of A. populnea (CHE) and some of its isolated compounds. The phytochemical study of the CHE was carried Out affording the isolation of methyl populnoate (1), populnoic acid (2), and stigmast-5-en-3-O-beta-(D-glucopyranoside) (3). This is the first time that the presence of compound 3 in A. populnea is reported. The results showed that the CHE presents antifungal and antibacterial activities, especially against Candida glabrata and Candida albicans, for which the CHE showed IC(50) values of 0.7 mu g mL(-1) and 5.5 mu g mL(-1), respectively, while amphotericin B showed an IC(50) value of 0.1 mu g mL(-1) against both microorganisms. Compounds 1-3 were inactive against all tested microorganisms. In the antileishmanial activity test against Leishmania donovani, the CHE showed an IC(50) value of 52 mu g mL(-1), while compounds 2 and 3 displayed an IC(50) value of 18 mu g mL(-1). In the antimalarial assay against Plasmodium falciparum (D6 and W2 clones), it was observed that all evaluated samples were inactive. In order to compare the effect on the parasites with the toxicity to mammalian cells, the cytotoxicity activity of the isolated compounds was evaluated against Vero cells, showing that all evaluated samples exhibited no cytotoxicity at the maximum dose tested.

Evaluation of the genotoxic and cytotoxic effects of crude extracts of Cordia ecalyculata and Echinodorus grandiflorus

Ethnopharmacological relevance: Cordia ecalyculata Veil. and Echinodorus grandiflorus (Cham. & Schltdl) Micheli are extensively used in Brazil as therapeutic preparations for indigenous groups and the general population. These plants have been used in the folk medicine as: tonic, diuretic, anti-inflammatory, appetite suppressants, for the treatment of snake bites, and weight loss. Aim of the study: In this study, it was verified the possible cytotoxic and genotoxic effects of the crude extracts of. Cordia ecalyculata and Echinodorus grandiflorus, as well as their effectiveness in treating obesity. Materials and methods: The Micronucleus Test was used for the evaluation of possible clastogenic and aneugenic effects, and the Comet Assay was used for the evaluation of single-strand and double-strand DNA breaks. The cytotoxic effects of the crude extracts were verified by PCE/NCE ratio. Swiss mice (Mus musculus) were used as the experimental model. Results: It was observed a significant (P < 0.05) increase, dose-independent, in the average frequency of micronucleated erythrocytes in peripheral blood in mice treated with either the Cordia ecalyculata or Echinodorus grandiflorus extracts, in comparison with the negative control. There were no significant differences (P > 0.05) in the frequency of micronucleated polychromatic erythrocytes for both extract treatment. We observed that treatment with the Cordia ecalyculata extract at concentrations of 1000 and 2000 mg/kg bw resulted in a PCE/NCE ratio that was larger (P < 0.05) than the negative control. After 15 days of daily treatment. a dose of 2000 mg/kg bw of either phytotherapeutic did not reduce body mass gain or the amount of food consumed by Swiss mice when compared with the negative control (P > 0.05). Conclusion: The results of this study allowed us to infer that the crude extracts of Cordia ecalyculata and Echinodorus grandiflorus do not display cytotoxic or genotoxic activities. However, they do possess weak clastogenic activity (without significance) on peripheral blood cells. Contrary to commonly held beliefs it was also found in this study that the extracts are not effective for obesity treatments. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Antiprotozoal, Schistosomicidal, and Antimicrobial Activities of the Essential Oil from the Leaves of Baccharis dracunculifolia

Baccharis dracunculifolia DC. (Asteraceae), popularly known as alecrim do campo, is a native plant from Brazil used in folk medicine as febrifuge, anti-inflammatory, antiseptic, and to treat skin sores. Also, B. dracanculifolia is the most important plant source of the Brazilian green propolis. which is recognized for its antiseptic and antiprotozoal activities. This study aimed at investigating the in vitro antiprotozoal. schistosomicidal, and antimicrobial activities of the essential oil from the leaves of R. dracunculifolia. The essential oil was obtained by hydrodistillation and analyzed by CC and GC/MS, which allowed the identification of 14 compounds, mainly oxygenated sesquiterpenes, such as ( E)nerolidol (33.51%) and spathulenol (16.24%). The essential oil showed activity against promzistigote forms of Leishmania donovani, with IC(50), values of 42 mu g/ml. The essential oil displayed high activity in the schistosomicidal assay, since all pairs of Schistosoma mansoni adult worms were dead after incubation with the essential oil (10, 50, and 100 fig/m1). B. dracunculifolia essential oil was neither cytotoxic against Vero cells, nor active in the antimicrobial and antiplasmodial assays.

Evaluation of the genotoxic and antigenotoxic potential of Baccharis dracunculifolia extract on V79 cells by the comet assay

Baccharis dracunculifolia (Asteraceae), the main botanical source of green propolis, is a shrub of the Brazilian `cerrado`. In folk medicine it is used as an anti-inflammatory agent, mainly for the treatment of gastrointestinal diseases. The aim of the present study was to evaluate the genotoxic and antigenotoxic effects of B. dracunculifolia ethyl acetate extract (Bd-EAE) on Chinese hamster lung fibroblasts (V79 cells) by the comet assay. Methyl methanesulfonate (MMS; 200 mu M) was used as an inducer of DNA damage. Genotoxicity was evaluated using four different concentrations of Bd-EAE: 12.5, 25.0, 50.0 and 100.0 mu g ml(-1). Antigenotoxicity was assessed before, simultaneously, and after treatment with the mutagen. The results showed a significant increase in the frequency of DNA damage in cultures treated with 50.0 and 100.0 mu g ml(-1) Bd-EAE. Regarding its antigenotoxic potential, Bd-EAE reduced the frequency of DNA damage induced by MMS. However, this chemopreventive activity depended on the concentrations and treatment regimens used. The antioxidant activity of phenolic components present in Bd-EAE may contribute to reduce the alkylation damage induced by MMS. In conclusion, our findings confirmed the chemopreventive activity of Bd-EAE and showed that this effect occurs under different mechanism. Copyright (C) 2009 John Wiley & Sons, Ltd.

In vitro cytotoxic activity of Baccharis dracunculifolia and propolis against HEp-2 cells

Baccharis dracunculifolia is the most important vegetal source of propolis in southeast Brazil, and researchers have been investigating its biological properties. Propolis is a complex resinous hive product collected by bees from several plants, showing a very complex chemical composition. It has been employed since ancient times due to its therapeutic properties, such as antimicrobial, anti-inflammatory, antioxidant, immunomodulatory and antitumour activities, among others. The goal of this work was to compare the cytotoxic action of B. dracunculifolia, propolis and two isolated compounds (caffeic and cinnamic acids) on human laryngeal epidermoid carcinoma (HEp-2) cells in vitro. These cells were incubated with different concentrations of each variable, and cell viability was assessed by the crystal violet method. Lower concentrations of B. dracunculifolia (extract and essential oil), propolis, as well as caffeic and cinnamic acids, showed no cytotoxic activity against HEp-2 cells. On the other hand, elevated concentrations (50 and 100 mu g per 100 mu L) exerted a cytotoxic action, and propolis showed a more efficient action than its vegetal source and isolated compounds. Further investigation is still needed in order to explore the potential of these variables as antitumour agents and to understand their mechanisms of action.

Evaluation of protective effects of fish oil against oxidative damage in rats exposed to methylmercury

The present study evaluates a possible protective effect of fish oil against oxidative damage promoted by methylmercury (MeHg) in sub-chronically exposed rats. Reduced glutathione peroxidase and catalase enzyme activity and reduced glutathione levels were observed in MeHg-exposed animals compared to controls. Methylmercury exposure was also associated with DNA damage. Administration of fish oil to the methylmercury-exposed animals did not ameliorate enzyme activity or glutathione levels. On the other hand, a significant DNA protective effect (about 30%) was observed with fish oil treatment. There were no differences in the total mercury concentration in rat liver, kidney, heart or brain after MeHg administration with or without fish oil co-administration. Histopathological analyses showed a significant leukocyte infiltration in rat tissues after MeHg exposure, but this effect was significantly reduced after co-administration of fish oil. Taken together, our findings demonstrate oxidative damage even after low-level MeHg exposure and the protective effect of fish oil. This protection seems not to be related to antioxidant defenses or mercury re-distribution in rat tissues. It is probably due to the anti-inflammatory effects of fish oil. (C) 2010 Elsevier Inc. All rights reserved.

Prior and concomitant dehydroepiandrosterone treatment affects immunologic response of cultured macrophages infected with Trypanosoma cruzi in vitro?

DHEA, a steroid hormone synthesized from cholesterol by cells of the adrenal cortex, plays an essential role in enhancing the host`s resistance to different experimental infections. Receptors for this hormone can be found in distinct immune cells (especially macrophages) that are known to be the first line defense against Trypanosoma cruzi infection. These cells operate through an indirect pathway releasing nitric oxide (NO) and cytokines such TNF-alpha and IL-12 which in turn trigger an enhancement of natural killer cells and lymphocytes which finally secrete pro and anti-inflammatory cytokines. The effects of pre- and post-infection DHEA treatment on production of IL-12, TNF alpha and NO were evaluated. T. cruzi infected macrophages post treated with DHEA displayed enhanced concentrations of TNF-alpha, IL-12 and NO. Probably, the mechanisms that induced the production of cytokines by infected cells are more efficient when the immune system has been stimulated first by parasite invasion, suggesting that the protective role of DHEA is greater when administered post infection. (C) 2011 Elsevier B.V. All rights reserved.

Deconstructing Tick Saliva NON-PROTEIN MOLECULES WITH POTENT IMMUNOMODULATORY PROPERTIES

Dendritic cells (DCs) are powerful initiators of innate and adaptive immune responses. Ticks are blood-sucking ectoparasite arthropods that suppress host immunity by secreting immunomodulatory molecules in their saliva. Here, compounds present in Rhipicephalus sanguineus tick saliva with immunomodulatory effects on DC differentiation, cytokine production, and costimulatory molecule expression were identified. R. sanguineus tick saliva inhibited IL-12p40 and TNF-alpha while potentiating IL-10 cytokine production by bone marrow-derived DCs stimulated by Toll-like receptor-2, -4, and -9 agonists. To identify the molecules responsible for these effects, we fractionated the saliva through microcon filtration and reversed-phase HPLC and tested each fraction for DC maturation. Fractions with proven effects were analyzed by micro-HPLC tandem mass spectrometry or competition ELISA. Thus, we identified for the first time in tick saliva the purine nucleoside adenosine (concentration of similar to 110pmol/mu l) as a potent anti-inflammatory salivary inhibitor of DC cytokine production. We also found prostaglandin E(2) (PGE(2) similar to 100 nM) with comparable effects in modulating cytokine production by DCs. Both Ado and PGE(2) inhibited cytokine production by inducing cAMP-PKA signaling in DCs. Additionally, both Ado and PGE(2) were able to inhibit expression of CD40 in mature DCs. Finally, flow cytometry analysis revealed that PGE(2), but not Ado, is the differentiation inhibitor of bone marrow-derived DCs. The presence of non-protein molecules adenosine and PGE(2) in tick saliva indicates an important evolutionary mechanism used by ticks to subvert host immune cells and allow them to successfully complete their blood meal and life cycle.

Minocycline and oral pigmentation

Minocycline is a semisynthetic tetracycline used in the treatment of inflammatory acne because of its broad spectrum of activity, less common development of resistant organisms, and its anti-inflammatory effects. A number of adverse reactions are reported, including skin and oral pigmentation. This paper details the pharmacology of minocycline and describes the pigmentation and likely mechanisms active in both hard and soft tissues. Oral pigmentation usually involves the hard tissues only and presents typically as a discrete band occupying the central zone of the alveolar mucosa and palate. As with other sites, it may persist following withdrawal of the drug. Early recognition by the dental practitioner may allow an alternative form of therapy to be sought, minimizing the likelihood of a longterm aesthetic problem.

Topical penetration of commercial salicylate esters and salts using human isolated skin and clinical microdialysis studies

Aims The penetration of active ingredients from topically applied anti-inflammatory pharmaceutical products into tissues below the skin is the basis of their therapeutic efficacy. There is still controversy as to whether these agents are capable of direct penetration by diffusion through the tissues or whether redistribution in the systemic circulation is responsible for their tissue deposition below the application site. Methods The extent of direct penetration of salicylate from commercial ester and salt formulations into the dermal and subcutaneous tissue of human volunteers was determined using the technique of cutaneous microdialysis. We also examined differences in the extent of hydrolysis of the methylester of salicylate applied topically in human volunteers and in vitro skin diffusion cells using full-thickness skin and epidermal membranes. Results The present study showed that whilst significant levels of salicylate could be detected in the dermis and subcutaneous tissue of volunteers treated with the methylsalicylate formulation, negligible levels of salicylate were seen following application of the triethanolamine salicylate formulation. The tissue levels of salicylate from the methylsalicylate formulation were approx. 30-fold higher than the plasma concentrations. Conclusion The absorption and tissue concentration profiles for the commercial methylsalicylate formulation are indicative of direct tissue penetration and not solely redistribution by the systemic blood supply.

Distribution of interleukin-2,-4,-10, tumour necrosis factor-alpha and transforming growth factor-beta mRNAs in oral lichen planus

In the present study. MRNA for the cytokines interleukin-2 (IL-2), IL-4, IL-10 tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor beta-1 (TGF-beta-1) were investigated in oral lichen planus (OLP) lesions using in situ hybridization with S-35-labelled oligonucleotide probes on frozen tissue sections. In addition, the expression of interferon-gamma (IFN-gamma), IL-10 and IL-4 mRNAs was analysed in cultured lesional T lymphocytes from oral lichen planus by polymerase chain reaction. Cells expressing mRNA for IL-2, IL-4, IL-10, TNF-alpha and TGF-beta(1) were found in all the biopsies studied. Approximately 1-2% of the total number of infiltrating cells in the lesions were positive for each of the different cytokine mRNAs. Most biopsies contained basement membrane-oriented, mRNA-positive cells. In the cultured T-cell lines, message for IFN-gamma was detected in all the patients, IL-10 in all but one, and IL-4 in just one of the seven patients investigated. The results suggest that mRNA for both pro- and anti-inflammatory cytokines, i.e., mixed T-helper 1 (T(H)1) and T(H)2 cytokine profiles, are generated simultaneously by a limited number of cells in chronic lesions of OLP. (C) 1999 Elsevier Science Ltd. All rights reserved.

A new small molecule C5a receptor antagonist inhibits the reverse-passive arthus reaction and endotoxic shock in rats

C5a is implicated as a pathogenic factor in a wide range of immunoinflammatory diseases, including sepsis and immune complex disease, Agents that antagonize the effects of C5a could be useful in these diseases. We have developed some novel C5a antagonists and have determined the acute anti-inflammatory properties of a new small molecule C5a receptor antagonist against C5a- and LPS-induced neutrophil adhesion and cytokine expression, as well as against some hallmarks of the reverse Arthus reaction in rats. We found that a single i.v. dose (1 mg/kg) of this antagonist inhibited both C5a- and LPS-induced neutropenia and elevated levels of circulating TNF-alpha, as well as polymorphonuclear leukocyte migration, increased TNF-alpha levels and vascular leakage at the site of immune complex deposition. These results indicate potent anti-inflammatory activities of a new C5a receptor antagonist and provide more evidence for a key early role for C5a in sepsis and the reverse Arthus reaction. The results support a role for antagonists of C5a receptors in the therapeutic intervention of immunoinflammatory disease states such as sepsis and immune complex disease.

Preliminary experiences with a single-patient trials service in general practice

Objective: To pilot a single-patient trials (SPTs) service in general practice, designed to improve decision-making about long-term medications for chronic conditions. Design: 12-week within-patient, randomised, double-blind, placebo-controlled, crossover comparison of ibuprofen with paracetamol for osteoarthritis, involving three pairs of two-week treatment periods for each participating patient. Setting and patients: Patients attending an academic general practice with a clinical diagnosis of osteoarthritis, with pain of at least a month's duration severe enough to warrant consideration of long-term non-steroidal anti-inflammatory drug (NSAID) use. Main outcome measures: Pain and stiffness; measures of overall arthritis compared with previous fortnight; preference for NSAID at the end of each two-week treatment period; use of escape analgesia; side effects; and management changes as a result of the SPTs. Results: Eight of 14 patients completed SPTs. One was a clear responder to NSAIDs, five were non-responders, and two were indefinite. Of the five who were using NSAIDs before the SPT, two continued and three ceased using them. Clinically useful information assisted decision-making for all eight participants. Medication management changed for six. Conclusions: Single-patient trials can be successfully implemented in general practice and might be a valuable method for GPs to identify patients who respond to medication for chronic stable conditions such as osteoarthritis, in which individual response to medication is variable.