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Background The identification of targets and new drugs to fight cancer is one the greatest challenges for Biotechnology researchers. Not only humans, but also animals are affected by this disease. It is estimated for example that one in every 3-4 dogs will develop some type of cancer during its lifetime, twice as much as the human being [1,2]. DNA methylation is an important epigenetic mechanism which control gene expression during cell proliferation and differentiation. Deregulation of this mechanism is one of the events which can contribute to the development of cancer [3]. The identification of epigenetic drugs, which are molecules that can revert aberrant DNA methylation, is one of the main areas of cancer research nowadays. In this regard, natural products are a rich source of possibilities to increase the arsenal of epigenetic drugs [1]. This study aims to analyze the cytotoxicity effect of curcumin treatments in DH82 canine histiocytic sarcoma cell line. This polyphenol derived from Curcuma longa has emerged as a potent multimodal cancer-preventing agent which modulates multiple cell signaling pathways and also been described as an inhibitor of DNA methylation[4]. The knowledge of the biological effects of these substances can pinpoint targets for the development of epigenetic drugs, with a positive impact for the treatment of canine and human cancer.

Background Phytochemical analysis of the fruits of Solanum lycocarpum, popularly known as “fruit of the wolf”, showed high concentrations of steroidal alkaloids, such as solasonine and solamargine which are substances with potential cytotoxic activity [1]. The cytotoxic activity displayed by these compounds may be due to presence of sugar moieties (rhamnose). Since there is interaction of glycoalkaloids with plasma membrane cholesterol leading to loss of membrane integrity, resulting in alterations in its permeability what induces cell death [2]. The aim of this study was to evaluate the cytotoxicity activity of the glycoalkaloids solamargine and solasonine purified from S. lycocarpum and commercial a-solanine alkaloid from potato sprout toward cell lines MCF-7 (human breast adenocarcinoma cell line), B16 (murine skin) and 3T3 (normal mouse embryo fibroblasts) by MTT.

Background Dermatophytes are adapted to grow in keratinized tissues such as skin, nail and hair. Trichophyton rubrum is the most frequent cause of dermatophytosis in Brazil and in the world [1]. Despite its incidence there are only a limited number of antifungal drugs available for clinical use and some drugs are highly toxic to humans. In this regard, chalcones and alkaloids are phytochemical products which provide a rich source of chemical diversity for the development of new antifungals. Chalcones inhibit the biosynthesis of the cell wall and activity of fatty acid synthase in yeast [2,3]. The glycoalkaloid a-Solanine purified from potate sprout presents antifungal activity by altering cell membrane integrity and inhibition of sporulation [4]. The aim of the present study was to evaluate the minimum inhibitory concentration (MIC) and cytotoxicity (by MTT) of trans-Chalcone and a-Solanine toward strain MYA3108 of T.rubrum and the keratinocyte cell line HaCat, in order to evaluate the potential use of these phytochemicals against fungal skin infection.

Background The dermatophytes belong to one of the main groups of pathogenic fungus, characterized by the use of the host’s keratin for its nutrition, which are the most common cause of fungal infection in the world, affecting millions of individuals annually, causing a huge economic impact [1]. Therefore, there was an increase in the search for new antifungal agents from natural sources, because the majority of the available drugs in the market presents a restricted number of cellular targets and there are reports of resistant fungal strain to these utilized drugs [2]. Glycoalkaloids from the Solanum lycocarpum plant (lobeira) presents several biological activities, such as cytotoxic and antimicrobial activities [3]. The goal of this work was determination the Minimum Inhibitory Concentration (MIC) of the solanine, solamargine and solasodine from the S. lycocarpum in addition to evaluate the effect of these alkaloids in the regeneration of the Trichophyton rubrum cell wall.

Background The detection of parasites in blood samples by DNA based assays is mostly performed by using the PCR technique, but due to the time of the reactions and costs involved, they still cannot be used in large-scale in routine laboratories. Recently, an alternative are assays based on the technique of Loop-mediated Isothermal Amplification (LAMP), which requires a shorter reaction time, higher specificity and has a lower cost [1]. This study aimed to develop a LAMP assay for the detection of Ehrlichia canis, a Gram-negative endobacteria and the etiologic agent of canine monocytic ehrlichiosis (CME), a major disease transmitted by ticks to dogs [2]. DNA extracted from blood samples of dogs presented to veterinary clinics and laboratories in the city of Ribeirao Preto, showing clinical signs indicative of EMC, were used in the assays. The samples were also previously diagnosed by PCR for presence of E.canis. Two sets of LAMP primers were used for the amplification of a fragment of the genes p30 (P30) and Heat-shock operon groESL (GRO).

Background The Brazilian National Cancer Institute (INCA) estimated last year almost forty thousand new cancer cases of laryngeal carcinoma, melanoma, tracheal, bronchial and lung cancer. It is known that multidrug resistance and unspecific toxicity are the major challenges for commercial anticancer drugs [1]. In this regard, natural compounds and derivatives are considered as a source of novel antitumor drugs. Among these molecules, chalcones have gained pharmacological importance due its mechanisms of action related to apoptosis induction [2]. Here we characterized the cytotoxicity of four chalcones toward three tumor cell lines: Hep-2 (human laryngeal squamous carcinoma cells), B-16 (mouse melanoma), A549 (human lung adenocarcinoma epithelial cells) and one normal cell line: 3T3 (mouse fibroblasts).

Background Cancer is a leading cause of death among dogs worldwide [1]. The disease results from alterations in expression of genes that control the cell cycle, including proliferation, differentiation and programmed cell death [2]. The interest in understanding the molecular aspects of cancer in humans and dogs is driven by the possibilities of identification of novel targets for the development of new anticancer compounds [3]. A molecular tool that has been used for this purpose is the RNA interference (RNAi) technique which exploits the mechanism of posttranscriptional silencing, mediated by molecules of double-stranded RNA that trigger degradation of complementary mRNAs [4]. However, for the application of this technique, important aspects must be investigated, since not all cell strains are susceptible to silencing by RNAi, and often the intracellular release of the interfering RNAs has low efficiency [5]. In this work we evaluated the efficiency of RNAi in silencing of topoisomerase IIA, a target for many anticancer compounds, in the canine histiocytic sarcoma DH82 cell line.

Background The presence of high levels of aflatoxin is a serious problem to the production of raw peanuts and peanut crumbs. The high incidence of aflatoxin in peanuts in our country is mainly due to problems in primary production. High humidity and temperature conditions increase the likelihood of Aspergillus development and aflatoxins production, which is worsened during rainy weather [1]. Aflatoxins may remain in the food after the death of fungus without visible alterations [2]. The effects of aflatoxins on human and animal health, besides resistance of fungi to conventional antifungal agents has motived the search for new inhibitors. The research of marine natural products from sponges has been considered as a promising source for the development of new antifungal agents in order to discover compounds more effective and less toxic [3]. The objective of this study was to evaluate the antifungal activity of 21 marine natural compounds toward an aflatoxigenic A.flavus ATCC strains.

Background Microalgae are becoming a viable model for the expression of recombinant proteins. However, suitable levels of expression for commercial production have not yet been obtained. One way to increase the heterologous protein production is the codon optimization of the target gene so that it presents the preferential codons used by the host organism according to its own pool of transfer RNA (tRNA). For codon optimization the Codon Usage Database (CUD; http://www.kazusa.or.jp/codon) has been used. The database provides codon frequency tables based on gene transcripts, regardless of their level of expression. Therefore, the aim of this study was to determine if there are changes in the frequency of codons used when taking into account the level of expression of genes, considering the 50 most expressed genes and 50 least expressed genes from the microalgae Chlamydomonas reinhardtii.

Background Dermatophytosis are fungal infections caused by keratinophilic fungi known as dermatophytes and classified in three genera: Trichophyton, Epidermophyton and Microsporum. Trichophyton rubrum is the most frequent species associated to dermatophytosis worldwide [1]. The infections caused by dermatophytes are not lethal, but are difficult to treat and uncomfortable. In the case of T. rubrum, they tend to be chronic, and although the superficial infections are more common, cases of deep infection have been reported in immunocompromised patients [2][3]. The number of antifungal drugs are still limited, and the acquired resistance for some of clinical antifungal have been shown as well as the side effects that have been promoted by them. Reasons for the challenge in development of new antifungal drugs are the similarities shared by fungal and mammalian cells and the lack of knowledge about the biology of these pathogens. Recent evidences have shown that the fatty acid sinthase (FAS) is an interesting antifungal target [4] because of marked differences between human and fungal cells. The aim of this study was to evaluate the antifungal activity of four flavonoids described as FAS inhibitors and verify the modulation of genes in the pathway of fatty acid synthesis in T. rubrum growth in presence of the most effective one as FAS inhibitor.

Background Trichophyton rubrum is a dermatophyte that causes mostly superficial mycoses in skin, hair and nails, but an invasive course has been described in immunocompromised patients [1]. The resistance to usual antifungal drugs has been observed in T.rubrum what drives an increasing demand for new antifungal drugs. Chalcones are flavonoids found in plants that exhibit pronounced antifungal activity, most likely acting on the cell wall [2,3]. The aim of this study was to evaluate the modulation of expression of genes involved in cell wall synthesis of T.rubrum in the presence of chalcones.