Beauvericin and enniatin B effects on a human lymphoblastoid Jurkat T-cell model.

Several mycotoxins exert their effect on the immunological system; some are classified as immunotoxic. Jurkat T-cells were used to study toxic effects of beauvericin (BEA) and enniatin B (ENN B). Both are not legislated mycotoxins with increasing presence in feed and food. Concentrations studied were from 1 to 15 µM at 24, 48 and 72 h. Cell death by increasing the percentage of apoptotic/necrotic cells was: BEA > ENN B. IC50 values ranged from 3 to 7.5 µM for BEA. ENN B 15 µM decreased viability (21-29%). The percentage of apoptotic/necrotic cells was BEA > ENN B at 24 h but not at 48 h. Caspase-3&7 activation profile varied, although both mycotoxins increased this activation. No difference in ROS production for any mycotoxin was observed. Arrest in S phase for both mycotoxins was obtained. BEA increased the percentage of DNA in the tail (18% and 20%) with respect to the control, whereas not for ENN B. In summary, cytotoxicity of BEA involved mitochondrial alterations; while ENN B only at highest concentrations and time assayed. BEA had cell cycle disturbances and apoptotic and apoptotic/necrotic cells increased; for ENN B these were not evident. Different toxic responses in Jurkat T-cells may be involved in BEA and ENN B toxicity.

Toxicidad del Bisfenol A: Revisión / Toxicity of Bisphenol A: review

El Bisfenol A (BPA) es un compuesto químico muy utilizado en la industria. Se emplea como elemento y/o componente destinado a la fabricación de plásticos y resinas epoxi. Los plásticos y resinas producidas con BPA. se usa para la producción de recipientes con distintas aplicaciones, como puede ser; el envase de alimentos y bebidas, vajillas, papel térmico y dispositivos utilizados en el campo de la medicina, etc. Los seres humanos están expuestos a BPA de manera habitual, siendo la exposición a través de la dieta, (envases de comida y bebida) la fuente más importante de riesgo. Los materiales que permanecen en contacto con los alimentos son un punto clave de fuente contaminación, por ello deben estar evaluados y regulados para su utilización. El BPA se considera un disruptor endócrino con capacidad de alterar funciones y sistemas del organismo. En los últimos años, diversos estudios han relacionado la exposición a BPA con la aparición de efectos adversos para la salud. La EFSA, en su última opinión científica a cerca del BPA, concluye que, este compuesto no presenta riesgos para la salud de los expuestos y por tanto, actualmente en la Unión Europea, el BPA se considera un producto autorizado para la utilización como material destinado a entrar en contacto con los alimentos. Sin embargo, se continúa investigando sobre el BPA y sus posibles efectos adversos. La presente revisión recoge los estudios más recientes, 'in vitro' e 'in vivo' sobre la toxicidad del BPA, agrupados en las categorías, donde se ha visto implicación del BPA, en el estado de salud, siendo estas: proliferación celular y cáncer, alteraciones en el desarrollo y maduración celular, estrés oxidativo y daño en el material genético y afectación a nivel metabólico, reproductivo, cardiovascular y neuronal (AU)

Bisfenol A (BPA) is a chemical compound commonly used in industry. It is generally used as an element and/or component in the manufacturing of plastics and epoxy resins. These plastics and resins are used in the manufacture of containers with differentpurposes, for example; in the packaging of food and drinks, crockery, thermic paper, devices used in the medical field etc. Human beings are commonly exposed to BPA, being the diet (food and drink packaging) the highest exposure factor and therefore a key contamination spot. For this reason it is necessary that the usage of materials which are in contact with food is properly evaluated and regulated. BPA is considered a endocrine disruptor, with the capacity to alter functions and systems in the organism. Several studies have recently proposed a relation between the exposure to BPA and the appearance of adverse effects for the health. However, the EFSA recently concluded in their latest scientific opinion on the topic, that this compound does not imply any risk for the health of the exposed population. Therefore the EU considers BPA an authorised product to be used as material to enter in contact with food. However research on BPA and its potential negative effects is still ongoing. This review contains the latest 'in vitro' and 'in vivo' studies about BPA toxicity, these studies are grouped in the following categories (regarding different implications); cellular proliferation and cancer, alterations in development and cellular maturation, oxidative stress, damage to genetic material and finally alterations at a metabolic, reproductive, cardiovascular or neuronal level (AU)

Efectos tóxicos de alternariol por ensayos in vitro: revisión / Toxic effects of alternariol by in vitro assays: a review

Las micotoxinas son metabolitos secundarios producidos por hongos del genero Aspergillus, Penicillium, Fusarium y Alternaria. Las micotoxinas más abundantes son aflatoxinas (Aspergillus), ocratoxina A (Penicillium), fumonisinas, zearalenona, deoxinivalenol (Fusarium) y alternariol (Alternaria). De las especies de Alternaria, A. alternata es la especie productora más importante de micotoxinas. Todas están consideradas como contaminantes tóxicos que están presentes en alimentos de consumo diario. Esta revisión se centra en estudios in vitro relacionados con la respuesta y citotoxicidad a la micotoxina de Alternaria, alternariol (AOH). Para ello, se ha realizado una búsqueda bibliográfica de los artículos de AOH disponible en bases de datos como: Pubmed, Scopus, Science Direct y Current Contents en los últimos catorce años. Así pues, el objetivo de la revisión bibliográfica es evaluar los efectos de AOH investigados mediante ensayos in vitro (AU)

Mycotoxins are secondary metabolites produced by genera fungus of: Aspergillus, Penicillium, Fusarium and Alternaria. The most frequent mycotoxins are: aflatoxins (Aspergillus), ochratoxin A (Penicillium), fumonisins, zearalenone, deoxynivalenol (Fusarium) and alternariol (Alternaria). Among all Alternaria spp, A. Alternata is the most producer mycotoxin. All mycotoxins are considered toxic contaminants present in food of daily consumption. This review is based on in vitro studies where response and toxicity in cells of Alternaria mycotoxin, alternariol (AOH) have been carried out. In this sense a bibliographic search of AOH papers available in on-line data bases such as: Pubmed, Scopus, Science Direct and Current Contents in the last fourteen years, have been collected. The main objective of this bibliographic review is to evaluate the AOH effects detected in in vitro assay (AU)

Reactive oxygen species involvement in apoptosis and mitochondrial damage in Caco-2 cells induced by enniatins A, A1, B and B1.

The cytotoxic effects, the generation of reactive oxygen species (ROS) and lipid peroxidation (LPO) as well as the cell cycle disruption, the induction of apoptosis and changes in mitochondrial membrane potential (ΔΨm) as a function of increasing time have been determined in human colorectal adenocarcinoma (Caco-2) cells after exposure to enniatins (ENs) A, A1, B and B1. IC50 values obtained by the MTT and Neutral Red assay, after 24, 48 and 72 h of exposure ranged from 0.5±0.1 to >15 µM. A significant increase (p≤0.05) in ROS generation and LPO production, as determined by the fluorescent probe H2-DCFDA and TBARS method respectively, was observed for all mycotoxins tested at 3.0 µM concentration. The highest increase in ROS generation (2.6 fold higher than control) and LPO production (111%, as compared to control) was observed with EN A. Cell cycle was significantly arrested at G2/M phase after 24 h of exposure to EN A, A1, B1, whereas after 72 h of exposure an arrest in S phase was observed almost for all mycotoxins tested. Moreover, after 24 and 48 h of exposure, ENs increased the early apoptotic cells, whereas after 72h of exposure necrosis was observed. In addition the loss of ΔΨm was produced on Caco-2 cells after ENs exposure. ENs A, A1, B and B1 cytotoxicity involved early ROS generation that induced LPO oxidative damage, apoptosis and necrosis via the mitochondrial pathway. ENs A, A1 and B1 induced DNA damage. However the same effects cannot be proposed for EN B. Further studies on the toxicological effects induced by ENs A, A1, B and B1 are needed.

Beauvericin-induced cytotoxicity via ROS production and mitochondrial damage in Caco-2 cells.

The cytotoxicity of beauvericin (BEA) on human colon adenocarcinoma (Caco-2) cells was studied as a function of time. Moreover, the oxidative damage and cell death endpoints were monitored after 24, 48 and 72 h. After BEA exposure, the IC50 values ranged from 1.9 ± 0.7 to 20.6 ± 6.9 µM. A decrease in reduced glutathione (GSH; 31%) levels, as well as an increase in oxidized glutathione (GSSG, 20%) was observed. In the presence of BEA, reactive oxygen species (ROS) level was highly increased at an early stage with the highest production of 2.0-fold higher than the control that was observed at 120 min. BEA induced cell death by mitochondria-dependent apoptotic process with loss of the mitochondrial membrane potential (ΔΨm; 9% compared to the control), increase in LPO level (from 120% to 207% compared to the control) and reduced G0/G1 phase, with an arrest in G2/M, in a dose and time-dependent manner. Cell proliferation, apoptosis and ΔΨm determined, were in a dose- time-dependent manner. Moreover, DNA damage was observed after 12.0 µM concentration. This study demonstrated that oxidative stress is one of the mechanism involved in BEA toxicity, moreover apoptosis induction and loss of ΔΨm contribute to its cytotoxicity in Caco-2 cells.

Intestinal helminth fauna of the South American sea lion Otaria flavescens and fur seal Arctocephalus australis from northern Patagonia, Argentina.

We report on the intestinal helminth fauna of 56 South American sea lions, Otaria flavescens, and 5 South American fur seals, Arctocephalus australis, from northern Patagonia, Argentina. A total of 97,325 helminth specimens were collected from sea lions. Gravid individuals were represented by 6 species of parasites: 1 digenean (Ascocotyle (Ascocotyle) patagoniensis), 1 cestode (Diphyllobothrium spp.), 3 nematodes (Uncinaria hamiltoni, Contracaecum ogmorhini s.s., Pseudoterranova cattani) and 1 acanthocephalan (Corynosoma australe). In addition, third-stage larvae of 2 nematodes (Contracaecum sp. and Anisakis sp. type I) and 3 juvenile acanthocephalans (Andracantha sp., Profilicollis chasmagnathi and Corynosoma cetaceum) were also collected. Andracantha sp., C. ogmorhini s.s. and P. chasmagnathi represent new host records. A total of 1516 helminth specimens were collected from fur seals. Gravid individuals were represented by three species of parasites, namely, Diphyllobothrium spp., C. ogmorhini s.s. and C. australe. In addition, larvae of Contracaecum sp. and P. cattani, juveniles of C. cetaceum and immature cestodes (Tetrabothriidae gen. sp.) were also collected. Corynosoma australe was the most prevalent and abundant parasite in both hosts, accounting for >90% of all specimens. Sea lions and furs seals from northern Patagonia harbour the intestinal helminth communities that could be predicted for otariids, i.e. the combination of species of the genera Corynosoma, Diphyllobothrium, Pseudoterranova, Contracaecum and, in pups, Uncinaria. Additionally, both species of otariid are apparently unsuitable hosts (i.e. non-hosts) for as many as five parasite taxa. The inclusion or exclusion of these species affects estimation of species richness at both component community (11 versus 6 species in sea lions; 7 versus 3 species in fur seals) and infracommunity (mean: 3.1 versus 2.6 in sea lions; 2.2 versus 1.7 species) levels. Information about the reproductive status of helminth species is often lacking in parasitological surveys on otariids and other marine vertebrates, but it is of significance to improve precision in parascript studies or ecological meta-analyses.

Toxicological interactions between the mycotoxins beauvericin, deoxynivalenol and T-2 toxin in CHO-K1 cells in vitro.

Beauvericin (BEA), deoxynivalenol (DON) and T-2 toxin (T-2) are important food-borne mycotoxins that have been implicated in human health. In this study, the acute toxicity of individual and combined mycotoxins (BEA, DON and T-2) were tested in immortalized hamster ovarian cells (CHO-K1) at 24, 48 and 72 h of exposure, by the tetrazolium salt (MTT) and neutral red (NR) assays. The IC(50) values obtained for all mycotoxins by the MTT and NR assays ranged from 0.017 to 12.08 µM and from 0.042 to 17.22 µM, respectively. Both, individual and combined mycotoxins demonstrated a significant cytotoxic effect in CHO-K1 cells in a dose-dependent manner. When mycotoxins were assayed individually, T-2 showed the strongest IC(50) values (from 0.017 to 0.052 µM), by both endpoints tested, followed by DON (0.53-2.30 µM) and BEA, showing this last one, the weakest IC(50) values (from 2.77 to 17.22 µM). On the other hand, cytotoxicity interactions were evaluated by the isobologram method. In acute binary tests, DON+BEA (CI=1.60-25.07) and DON+T-2 (CI=1.74-7.71) showed antagonism at 24, 48 and 72 h of exposure. By contrast, the binary BEA+T-2 combination (CI=0.35-0.78) showed synergism at all time of exposure tested. The tertiary BEA+DON+T-2 combination demonstrated synergism effect (CI=0.47-0.86) after 24 and 48 h of exposure; however moderate antagonistic effect (CI=1.14-1.60) was presented after 72 h of exposure at the lower doses. These results provide quantitative evidence regarding potentially important interactions between BEA, DON and T-2 depending of the time of exposure. The combination index-isobologram equation method can serve as a useful tool in food risk assessment. Due to the potent toxic effects of BEA, DON and T-2, its combined exposure might be an important trigger for development of several diseases in humans, from the mycotoxicological point of view, especially after long period of exposure time.

Reactive oxygen species induced by beauvericin, patulin and zearalenone in CHO-K1 cells.

The cytotoxic effects of mycotoxins, induction of reactive oxygen species (ROS) and generation of lipid peroxidation products in CHO-K1 cells were determined as function of increasing time of exposure and concentrations of beauvericin (BEA), patulin (PAT) and zearalenone (ZEA). The end points were evaluated after 24h of exposure, by the tetrazolium salt (MTT) and neutral red (NR) assays. The IC(50) values obtained on the MTT and NR assays ranged from 0.69 to 79.40 microM and 4.40 to 108.76 microM, respectively. To determine the intracellular production of ROS, the intensity of fluorescence emitted from the probe H(2)-DCFDA was measured. The relative intensity of fluorescence from cells incubated with BEA, PAT and ZEA was approximately 4-, 7- and 4-fold higher in comparison with control cells at 0 min, respectively. Lipid peroxidation induced by ROS generation was assessed using the thiobarbituric acid reactive substances (TBARS) method for 2, 24 and 48 h. The malondialdehyde (MDA) production was increased with BEA and PAT exposure in a concentration- and time-dependent manner. MDA was not increased after 1 and 5 microM ZEA exposures for 2h, but was slightly increased at 50 microM. In conclusion, PAT was the most cytotoxic mycotoxin to CHO-K1 cells, followed by BEA and ZEA. Mycotoxins reduce cell viability correlated with the increases of ROS generation and MDA formation in concentration- and time-dependent manner. These data suggested that cytotoxicity and ROS generation are mechanisms of mycotoxins mediated toxicity.