Search

Non-synonymous variation (NSV) of protein coding genes represents raw material for selection to improve adaptation to the diverse environmental scenarios in wild and livestock populations. Many aquatic species face variations in temperature, salinity and biological factors throughout their distribution range that is reflected by the presence of allelic clines or local adaptation. The turbot (Scophthalmus maximus) is a flatfish of great commercial value with a flourishing aquaculture which has promoted the development of genomic resources. In this study, we developed the first atlas of NSVs in the turbot genome by resequencing 10 individuals from Northeast Atlantic Ocean. More than 50,000 NSVs where detected in the ~ 21,500 coding genes of the turbot genome, and we selected 18 NSVs to be genotyped using a single Mass ARRAY multiplex on 13 wild populations and three turbot farms. We detected signals of divergent selection on several genes related to growth, circadian rhythms, osmoregulation and oxygen binding in the different scenarios evaluated. Furthermore, we explored the impact of NSVs identified on the 3D structure and functional relationship of the correspondent proteins. In summary, our study provides a strategy to identify NSVs in species with consistently annotated and assembled genomes to ascertain their role in adaptation.

There is a widely recognized need to reduce human activity's impact on the environment. Many industries of the leather and textile sector (LTI), being aware of producing a significant amount of residues (Keßler et al. 2021; Liu et al. 2021), are adopting measures to reduce the impact of their processes on the environment, starting with a more comprehensive characterization of the chemical risk associated with the substances commonly used in LTI. The present work contributes to these efforts by compiling and toxicologically annotating the substances used in LTI, supporting a continuous learning strategy for characterizing their chemical safety. This strategy combines data collection from public sources, experimental methods and in silico predictions for characterizing four different endpoints: CMR, ED, PBT, and vPvB. We present the results of a prospective validation exercise in which we confirm that in silico methods can produce reasonably good hazard estimations and fill knowledge gaps in the LTI chemical space. The proposed protocol can speed the process and optimize the use of resources including the lives of experimental animals, contributing to identifying potentially harmful substances and their possible replacement by safer alternatives, thus reducing the environmental footprint and impact on human health.

Data de publicació electrònica: 01-01-2023 Includes supplementary materials for the online appendix. Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis. This study was supported by the Spanish Ministry of Economy and Competitiveness, FEDER Grants (RTI2018-096847-B-C21, RTI2018-096847-B-C22 and RTI2018-097110-B-C21), Junta de Andalucía-FEDER Grant (P20-00938) and the European Union's Horizon 2020 research and innovation programme under grant agreement No. 817923 (AQUA-FAANG). We thank Geneaqua SL for their participation and financial support of sequencing. We acknowledge the bioinformatic support of the Centro de Supercomputación de Galicia (CESGA).

The antiproliferative activity of [Mn(CO)3(N^N)Br] (N^N = phendione 1, bipy 3) and of the two newly synthesized Mn complexes [Mn(CO)3(acridine)(phendione)]OTf (2) and [Mn(CO)3(di-triazole)Br] (4) has been evaluated by MTS against three tumor cell lines A2780 (ovarian carcinoma), HCT116 (colorectal carcinoma), HCT116doxR (colorectal carcinoma resistant to doxorubicin), and in human dermal fibroblasts. The antiproliferative assay showed a dose-dependent effect higher in complex 1 and 2 with a selectivity toward ovarian carcinoma cell line 21 times higher than in human fibroblasts. Exposure of A2780 cells to IC50 concentrations of complex 1 and 2 led to an increase of reactive oxygen species that led to the activation of cell death mechanisms, namely via intrinsic apoptosis for 2 and autophagy and extrinsic apoptosis for 1. Both complexes do not target DNA or interfere with cell cycle progression but are able to potentiate cell migration and neovascularization (for 2) an indicative that their application might be directed for initial tumor stages to avoid tumor invasion and metastization and opening a new avenue for complex 2 application in regenerative medicine. Interestingly, both complexes do not show toxicity in both in vivo models (CAM and zebrafish).

Turbot is an important flatfish widely distributed along the European coasts, whose fishery is centered in the North Sea. The commercial value of the species has boosted a successful aquaculture sector in Europe and China. Body growth is the main target of turbot breeding programs and is also a key trait related to local adaptation to temperature and salinity. Differences in growth rate and optimal growth temperature in turbot have been shown to be associated with a hemoglobin polymorphism reported more than 50 years ago. Here, we identified a Gly16Asp amino acid substitution in the β1 globin subunit by searching for genetic variation in the five functional globin genes within the whole annotated turbot genome. We predicted increased stability of the turbot hemoglobin by the replacement of the conserved Gly with the negative charged Asp residue that is consistent with the higher rate of αβ dimer assembly in the human J-Baltimore Gly16β->Asp mutant than in normal HbA. The turbot Hbβ1-Gly16 variant dominated in the northern populations examined, particularly in the Baltic Sea, while the Asp allele showed elevated frequencies in southern populations and was the prevalent variant in the Adriatic Sea. Body weight did not associate with the Hbβ1 genotypes at farming conditions (i.e., high oxygen levels, feeding ad libitum) after analyzing 90 fish with high growth dispersal from nine turbot families. Nevertheless, all data at hand suggest that the turbot hemoglobin polymorphism has an adaptive significance in the variable wild conditions regarding temperature and oxygen availability. Electronic supplementary material The online version of this article (10.1007/s10695-020-00872-y) contains supplementary material, which is available to authorized users.

© The Author(s) 2020, Pancreatic ductal adenocarcinoma (PDAC), the fourth leading cause of cancer death, has a 5-year survival rate of approximately 7–9%. The ineffectiveness of anti-PDAC therapies is believed to be due to the existence of a subpopulation of tumor cells known as cancer stem cells (CSCs), which are functionally plastic, and have exclusive tumorigenic, chemoresistant and metastatic capacities. Herein, we describe a 2D in vitro system for long-term enrichment of pancreatic CSCs that is amenable to biological and CSC-specific studies. By changing the carbon source from glucose to galactose in vitro, we force PDAC cells to utilize OXPHOS, resulting in enrichment of CSCs defined by increased CSC biomarker and pluripotency gene expression, greater tumorigenic potential, induced but reversible quiescence, increased OXPHOS activity, enhanced invasiveness, and upregulated immune evasion properties. This CSC enrichment method can facilitate the discovery of new CSC-specific hallmarks for future development into targets for PDAC-based therapies., We acknowledge and thank Dr. Nuria Malats and Jaime Villarreal from the Spanish National Cancer Research Center (CNIO) for RNA sequencing and analysis, funded by Fondo de Investigaciones Sanitarias (FIS) grant PI18/01347. We thank Patricia Sánchez-Tomero and Marina Ochando-Garmendia for technical assistance and support and Dr. Raúl Sánchez Lanzas for assistance with autophagy experiments. We want to particularly acknowledge the patients and the BioBank Hospital Ramón y Cajal-IRYCIS (PT13/0010/0002) integrated in the Spanish National Biobanks Network for its collaboration and, in particular, Adrián Povo Retana for macrophage isolation. We would also like to thank the Transmission Electron Microscopy Unit Laboratory, part of the UAM Interdepartmental Investigation Service (SIdI); Coral Pedrero for exceptional help with in vivo experiments; and the laboratories of Dr. Amparo Cano and Dr. José González Castaño for reagents and helpful discussions. S.V. was a recipient of an Ayuda de Movilidad del Personal Investigador del IRYCIS, a mobility grant from the Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain, and a pre-doctoral fellowship from the Comunidad de Madrid, Ayudas Para La Contratación De Investigadores Predoctorales Y Posdoctorales (PEJD-2017-PRE/BMD-5062), Madrid, Spain. This study was supported by a Rámon y Cajal Merit Award (RYC-2012-12104) from the Ministerio de Economía y Competitividad, Spain (to B.S.); funding from la Beca Carmen Delgado/Miguel Pérez-Mateo from AESPANC-ACANPAN Spain (to B.S.); a Conquer Cancer Now Grant from the Concern Foundation (Los Angeles, CA, USA) (to B.S.); a Coordinated grant (GC16173694BARB) from the Fundación Asociación Española Contra el Cáncer (AECC) (to B.S.); FIS grants PI18/00757 (to B.S.), PI16/00789 (to M.A.F.-M.), PI18/00267 (to L.G.-B.; co-financed through Fondo Europeo de Desarrollo Regional (FEDER) “Una manera de hacer Europa”); a Miguel Servet award (CP16/00121) (to P.S.); a Max Eder Fellowship of the German Cancer Aid (111746) (to P.C.H.); and the German Research Foundation (DFG, CRC 1279 “Exploiting the human peptidome for Novel Antimicrobial and Anticancer Agents”; to P.C.H.).

Funding Information: This research was funded by national funds through FCT?Funda??o para a Ci?ncia e a Tecnologia, I.P., Project MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020, Project LISBOA-01-0145-FEDER-007660), and national funds through FCT, POPH-Programa Operacional Po-tencial Humano, and FSE (European Social Fund) for the CEEC 2017 Initiative CEECIND/04566/2017. Additionally, this work was supported by the Portuguese Foundation for Science and Technology (FCT?Funda??o para a Ci?ncia e a Tecnologia) for funding through projects PEst 2015 2020, UID/Multi/04349/2013, RECI/QEQ-QIN/0189/2012, and UID/QUI/00100/2020. This work was financed by national funds from FCT?Funda??o para a Ci?ncia e a Tecnologia, I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences?UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy?i4HB. The NMR spectrometers at CERMAX are integrated with the national NMR Network and partially supported through project 022162. Funding Information: Funding: This research was funded by national funds through FCT–Fundação para a Ciência e a Tecnologia, I.P., Project MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020, Project LISBOA-01-0145-FEDER-007660), and national funds through FCT, POPH-Programa Operacional Po-tencial Humano, and FSE (European Social Fund) for the CEEC 2017 Initiative CEECIND/04566/2017. Additionally, this work was supported by the Portuguese Foundation for Science and Technology (FCT—Fundação para a Ciência e a Tecnologia) for funding through projects PEst 2015 2020, UID/Multi/04349/2013, RECI/QEQ-QIN/0189/2012, and UID/QUI/00100/2020. This work was financed by national funds from FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences—UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB. The NMR spectrometers at CERMAX are integrated with the national NMR Network and partially supported through project 022162. Funding Information: Acknowledgments: This work was funded by national funds through FCT—Fundação para a Ciência e a Tecnologia, I.P., Project MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020, Project LISBOA-01-0145-FEDER-007660). Additionally, this work was supported by the Applied Molecular Biosciences Unit—UCIBIO, which is financed by national funds from FCT (UIDP/04378/2020 and UIDB/04378/2020). The NMR spectrometers at CERMAX are integrated with the national NMR Network and partially supported through project 022162. Oscar A. Lenis-Rojas acknowledge national funds through FCT, POPH—Programa Operacional Potencial Humano, and FSE (European Social Fund) for the CEEC 2017 Initiative. Jhonathan Angel Araujo Fernández acknowledge Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES) and the program CAPES/PRINT Proc. 88887.470075/2019-00. We acknowledge I. Ferreira for preliminary viability testing. We also thank the Analytic Services of ITQB and C. Almeida for elemental analysis. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Made available in DSpace on 2022-01-28T00:27:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-09-12 publishersversion published

The human cancer cell xenograft in zebrafish embryos has become a very useful preclinical tool in oncology research. While many anticancer drugs have been assayed with this model, few studies regarding the toxicity limits of these drugs for the host have been addressed. Here, we evaluated the acute toxicity of five approved and routinely used human anticancer drugs embracing different mechanism action types: Carboplatin (CarboPt), Irinotecan (IT), Doxorubicin (DOX), Paclitaxel (PT) and Chloroquine (CQ). They were tested in zebrafish embryos using the Fish Embryo Acute Toxicity (FET) test at 0 and 72 hours per fertilization (hpf). Additionally, we compared those results with in vitro toxicity assays and could find notable differences between both models. Our results indicate that the toxicity data of a compound evaluated in vitro and in a FET test at 0 hpf do not guarantee a reliable toxicity determination for performing xenografts in zebrafish, being necessary additional toxicity studies using 72 hpf embryos, the starting point of drug treatment in this kind of preclinical assays.

The antiproliferative activity of [Mn(CO)

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest tumors, partly due to its intrinsic aggressiveness, metastatic potential, and chemoresistance of the contained cancer stem cells (CSCs). Pancreatic CSCs strongly rely on mitochondrial metabolism to maintain their stemness, therefore representing a putative target for their elimination. Since mitochondrial homeostasis de-pends on the tightly controlled balance between fusion and fission processes, namely mitochondrial dynamics, we aim to study this mechanism in the context of stemness. In human PDAC tissues, the mitochondrial fission gene DNM1L (DRP1) was overexpressed and positively correlated with the stemness signature. Moreover, we observe that primary human CSCs display smaller mitochondria and a higher DRP1/MFN2 expression ratio, indicating the activation of the mitochondrial fission. In-terestingly, treatment with the DRP1 inhibitor mDivi-1 induced dose-dependent apoptosis, especially in CD133+ CSCs, due to the accumulation of dysfunctional mitochondria and the subsequent energy crisis in this subpopulation. Mechanistically, mDivi-1 inhibited stemness-related features, such as self-renewal, tumorigenicity, and invasiveness and chemosensitized the cells to the cytotoxic effects of Gemcitabine. In summary, mitochondrial fission is an essential process for pancreatic CSCs and represents an attractive target for designing novel multimodal treatments that will more efficiently eliminate cells with high tumorigenic potential, This research was funded by the Pancreatic Cancer Research Fund, 2015 Award Round (P.S., C.H.); the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement n 602783 (CAM-PaC) (C.H.), theWorldwide Cancer Research Charity together with Fundación Científica Asociación Española contra el Cáncer (FCAECC) (19-0250) (P.S.); A Fero Foundation grant and a Coordinated grant (GC16173694BARB) from the Fundación Asociación Española Contra el Cáncer (AECC) (B.S.J.); and the Instituto de Salud Carlos III through the Miguel Servet Program (CP16/00121) and Fondo de Investigaciones Sanitarias (PI17/00082) (both co-financed by European funds (FSE: “El FSE invierte en tu futuro” and FEDER: “Una manera de hacer Europa,” respectively) (P.S.)

Published studies show that most of the human cancer xenograft studies in zebrafish embryos have used incubation temperatures in the range of 32&ndash, 34 &deg, C for 3&ndash, 6 days post-injection, trying to find a compromise temperature between the zebrafish embryos (28 &deg, C) and the human injected cells (37 &deg, C). While this experimental setup is widely used, a question remains: is possible to overcome the drawbacks caused by a suboptimal temperature for the injected cells? To clarify the effect of temperature and injected cells on the host, in this study, we analyzed the development and health of the last in response to different temperatures in the presence or absence of injected human cancer cells. Comparing different incubation temperatures (28, 34 and 36 &deg, C), we determined morphological abnormalities and developmental effects in injected and non-injected embryos at different time points. Besides this, the expression of selected genes was determined by qPCR to determine temperature affected metabolic processes in the embryos. The results indicate that an incubation temperature of 36 &deg, C during a period of 48 h is suitable for xenotransplantation without morphological or metabolic changes that could be affecting the host or the injected cells, allowing them to proliferate near their optimal temperature.

Due to the rapid elimination of bacteria through normal behaviour of filter feeding and excretion, the decontamination of hazardous contaminating bacteria from shellfish is performed by depuration. This process, under conditions that maximize shellfish filtering activity, is a useful method to eliminate microorganisms from bivalves. The microbiota composition in bivalves reflects that of the environment of harvesting waters, so quite different bacteriomes would be expected in shellfish collected in different locations. Bacterial accumulation within molluscan shellfish occurs primarily in the hepatopancreas. In order to assess the effect of the depuration process on these different bacteriomes, in this work we used 16S RNA pyrosequencing and metagenome prediction to assess the impact of 15 h of depuration on the whole hepatopancreas bacteriome of mussels collected in three different locations.

© 2021 by the authors., Metamorphosis is a captivating process of change during which the morphology of the larva is completely reshaped to face the new challenges of adult life. In the case of fish, this process initiated in the brain has traditionally been considered to be a critical rearing point and despite the pioneering molecular work carried out in other flatfishes, the underlying molecular basis is still relatively poorly characterized. Turbot brain transcriptome of three developmental stages (pre-metamorphic, climax of metamorphosis and post-metamorphic) were analyzed to study the gene expression dynamics throughout the metamorphic process. A total of 1570 genes were differentially expressed in the three developmental stages and we found a specific pattern of gene expression at each stage. Unexpectedly, at the climax stage of metamorphosis, we found highly expressed genes related to the immune response, while the biological pathway enrichment analysis in pre-metamorphic and post-metamorphic were related to cell differentiation and oxygen carrier activity, respectively. In addition, our results confirm the importance of thyroid stimulating hormone, increasing its expression during metamorphosis. Based on our findings, we assume that immune system activation during the climax of metamorphosis stage could be related to processes of larval tissue inflammation, resorption and replacement, as occurs in other vertebrates., This research was funded by the MCIN/AEI/10.13039/501100011033 grant number AGL2017-89648P to JR and by “ERDF A way of making Europe”. L. Guerrero-Peña was supported by a pre-doctoral fellowship of the Spanish FPI Research Training Program funded by Spanish Economy and Competitiveness Ministry, grant number (PRE2018-085475). L. Méndez-Martínez was supported by a pre-doctoral fellowship of the Xunta de Galicia, grant number (IN606A-2020/006).

Flatfish have a high market acceptance thus representing a profitable aquaculture production. The main farmed species is the turbot (Scophthalmus maximus) followed by Japanese flounder (Paralichthys olivaceous) and tongue sole (Cynoglossus semilaevis), but other species like Atlantic halibut (Hippoglossus hippoglossus), Senegalese sole (Solea senegalensis) and common sole (Solea solea) also register an important production and are very promising for farming. Important genomic resources are available for most of these species including whole genome sequencing projects, genetic maps and transcriptomes. In this work, we integrate all available genomic information of these species within a common framework, taking as reference the whole assembled genomes of turbot and tongue sole (>210× coverage). New insights related to the genetic basis of productive traits and new data useful to understand the evolutionary origin and diversification of this group were obtained. Despite a general 1:1 chromosome syntenic relationship between species, the comparison of turbot and tongue sole genomes showed huge intrachromosomic reorganizations. The integration of available mapping information supported specific chromosome fusions along flatfish evolution and facilitated the comparison between species of previously reported genetic associations for productive traits. When comparing transcriptomic resources of the six species, a common set of ~2500 othologues and ~150 common miRNAs were identified, and specific sets of putative missing genes were detected in flatfish transcriptomes, likely reflecting their evolutionary diversification.

Mussels along with clams and oyster represent the most important worldwide mollusk production. Among mussels, Mytilus chilensis and Mytilus galloprovincialis are the most important species, exceeding 300,000 tons, but other species like Mytilus edulis and Mytilus californianus have significant production. In this chapter, we focus on the relevance of mussel microbiota for aquaculture and, specifically, for human health. In some sections, due to the limited documentation available, information has been expanded to studies in other mollusks, such as oysters and clams, as a significant reference for future studies on mussels. Anyway, information on mollusk microbiota lags behind other aquaculture species, particularly fish, and this limitation is discussed in this chapter. Then, the demand for further work is highlighted considering the benefits of microbiota control for mollusk production and health.

The neural crest is a multipotent cell population that develops from the dorsal neural fold of vertebrate embryos in order to migrate extensively and differentiate into a variety of tissues. A number of gene regulatory networks coordinating neural crest cell specification and differentiation have been extensively studied to date. Although several publications suggest a common role for microRNA-145 (miR-145) in molecular reprogramming for cell cycle regulation and/or cellular differ entiation, little is known about its role during in vivo cranial neural crest development. By modifying miR-145 levels in zebrafish embryos, abnormal craniofacial development and aberrant pigmentation phenotypes were detected. By whole-mount in situ hybridization, changes in expression patterns of col2a1a and Sry-related HMG box (Sox) transcription factors sox9a and sox9b were observed in overexpressed miR-145 embryos. In agreement, zebrafish sox9b expression was downregulated by miR-145 overexpression. In silico and in vivo analysis of the sox9b 3 0UTR revealed a conserved potential miR-145 binding site likely involved in its post-transcriptional regulation. Based on these findings, we speculate that miR-145 participates in the gene regulatory network governing zebrafish chondrocyte differentiation by controlling sox9b expression. Fil: Steeman, Tomás José. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Argentina. Fil: Rubiolo, Juan Andrés. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Argentina. Fil: Sánchez, Laura E. Universidade de Santiago de Compostela. Facultad de Veterinaria. Departamento de Zoología Genética y Antropología Física. Fil: Calcaterra, Nora B. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Argentina. Fil: Weiner, Andrea María Julia. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Argentina.

12 páginas, 5 figuras.-- Antonio Figueras ... et al.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, The turbot is a flatfish (Pleuronectiformes) with increasing commercial value, which has prompted active genomic research aimed at more efficient selection. Here we present the sequence and annotation of the turbot genome, which represents a milestone for both boosting breeding programmes and ascertaining the origin and diversification of flatfish. We compare the turbot genome with model fish genomes to investigate teleost chromosome evolution. We observe a conserved macrosyntenic pattern within Percomorpha and identify large syntenic blocks within the turbot genome related to the teleost genome duplication. We identify gene family expansions and positive selection of genes associated with vision and metabolism of membrane lipids, which suggests adaptation to demersal lifestyle and to cold temperatures, respectively. Our data indicate a quick evolution and diversification of flatfish to adapt to benthic life and provide clues for understanding their controversial origin. Moreover, we investigate the genomic architecture of growth, sex determination and disease resistance, key traits for understanding local adaptation and boosting turbot production, by mapping candidate genes and previously reported quantitative trait loci. The genomic architecture of these productive traits has allowed the identification of candidate genes and enriched pathways that may represent useful information for future marker-assisted selection in turbot, This work was funded by the Spanish Government: projects Consolider Ingenio: Aquagenomics (CSD2007-00002) and Metagenoma de la Península Ibérica (CSD2007-00005), Ministerio de Economía y Competitividad and European Regional Development Funds (AGL2012-35904), and Ministerio de Economía y Competitividad (AGL2014-51773 and AGL2014-57065-R); and Local Government Xunta de Galicia (GRC2014/010). P.P. and D.R. gratefully acknowledge the Spanish Ministerio de Educación for their FPU fellowships (AP2010-2408, AP2012-0254). Funding to pay the Open Access publication charges for this article was provided by the Ministerio de Economía y Competitividad (AGL2014-51773) and Xunta de Galicia (GRC2014/010)

Ciguatoxins are polyether marine toxins that act as sodium channel activators. These toxins cause ciguatera, one of the most widespread nonbacterial forms of food poisoning, which presents several symptoms in humans including long-term neurological alterations. Earlier work has shown that both acute and chronic exposure of primary cortical neurons to synthetic ciguatoxin CTX3C have profound impacts on neuronal function. Thus, the present work aimed to identify relevant neuronal genes and metabolic pathways that could be altered by ciguatoxin exposure. To study the effect of ciguatoxins in primary neurons in culture, we performed a transcriptomic analysis using whole mouse genome microarrays, for primary cortical neurons exposed during 6, 24, or 72 h in culture to CTX3C. Here, we have shown that the effects of the toxin on gene expression differ with the exposure time. The results presented here have identified several relevant genes and pathways related to the effect of ciguatoxins on neurons and may assist in future research or even treatment of ciguatera. Moreover, we demonstrated that the effects of the toxin on gene expression were exclusively consequential of its action as a voltage-gated sodium channel activator, since all the effects of CTX3C were avoided by preincubation of the neurons with the sodium channel blocker tetrodotoxin The research leading to these results has received funding from the following FEDER cofounded-grants. From CDTI and Technological Funds, supported by Ministerio de Economía, Industria y Competitividad, AGL2014-58210-R, AGL2016-78728-R (AEI/FEDER, UE), ISCIII/PI16/01830 and RTC-2016-5507-2. From CDTI under ISIP Programme, Spain, IDI-20130304 APTAFOOD and ITC-20161072. From European Union POCTEP 0161-Nanoeaters -1-E-1, and Interreg AlertoxNet EAPA-317-2016. ABJ is recipient of a predoctoral fellowship from the Spanish Ministry of Education SI

Ciguatoxins are sodium channels activators that cause ciguatera, one of the most widespread nonbacterial forms of food poisoning, which presents with long-term neurological alterations. In central neurons, chronic perturbations in activity induce homeostatic synaptic mechanisms that adjust the strength of excitatory synapses and modulate glutamate receptor expression in order to stabilize the overall activity. Immediate early genes, such as Arc and Egr1, are induced in response to activity changes and underlie the trafficking of glutamate receptors during neuronal homeostasis. To better understand the long lasting neurological consequences of ciguatera, it is important to establish the role that chronic changes in activity produced by ciguatoxins represent to central neurons. Here, the effect of a 30 min exposure of 10-13 days in vitro (DIV) cortical neurons to the synthetic ciguatoxin CTX 3C on Arc and Egr1 expression was evaluated using real-time polymerase chain reaction approaches. Since the toxin increased the mRNA levels of both Arc and Egr1, the effect of CTX 3C in NaV channels, membrane potential, firing activity, miniature excitatory postsynaptic currents (mEPSCs), and glutamate receptors expression in cortical neurons after a 24 h exposure was evaluated using electrophysiological and western blot approaches. The data presented here show that CTX 3C induced an upregulation of Arc and Egr1 that was prevented by previous coincubation of the neurons with the NaV channel blocker tetrodotoxin. In addition, chronic CTX 3C caused a concentration-dependent shift in the activation voltage of NaV channels to more negative potentials and produced membrane potential depolarization. Moreover, 24 h treatment of cortical neurons with 5 nM CTX 3C decreased neuronal firing and induced synaptic scaling mechanisms, as evidenced by a decrease in the amplitude of mEPSCs and downregulation in the protein level of glutamate receptors that was also prevented by tetrodotoxin. These findings identify an unanticipated role for ciguatoxin in the regulation of homeostatic plasticity in central neurons involving NaV channels and raise the possibility that some of the neurological symptoms of ciguatera might be explained by these compensatory mechanisms.

The production of Manila clam (Ruditapes philippinarum) is seriously threatened by the protistan parasite Perkinsus olseni. We characterized and compared gene expression of Manila clam haemocytes in response to P. olseni in a time-course (10 h, 24 h, 8 d) controlled laboratory challenge (LC), representing the first step of infection, and in a more complex infection in the wild (WI), using a validated oligo-microarray containing 11,232 transcripts, mostly annotated. Several immune-genes involved in NIK/NF-kappaB signalling, Toll-like receptor signalling and apoptosis were activated at LC-10 h. However, down-regulation of genes encoding lysozyme, histones, cathepsins and heat shock proteins indicated signals of immunodepression, which persisted at LC-24 h, when only down-regulated genes were detected. A rebound of haemocyte activity occurred at LC-8 d as shown by up-regulation of genes involved in cytoskeleton organization and cell survival. The WI study showed a more complex picture, and several immune-relevant processes including cytoskeleton organization, cell survival, apoptosis, encapsulation, cell redox- and lipid-homeostasis were activated, illustrating the main mechanism of host response. Our results provide useful information, including potential biomarkers, to develop strategies for controlling Manila clam perkinsosis.

Growth is among the most important traits for animal breeding. Understanding the mechanisms underlying growth differences between individuals can contribute to improving growth rates through more efficient breeding schemes. Here, we report a transcriptomic study in muscle and brain of fast- and slow-growing turbot (Scophthalmus maximus), a relevant flatfish in European and Asian aquaculture. Gene expression and allelic association between the two groups were explored. Up-regulation of the anaerobic glycolytic pathway in the muscle of fast-growing fish was observed, indicating a higher metabolic rate of white muscle. Brain expression differences were smaller and not associated with major growth-related genes, but with regulation of feeding-related sensory pathways. Further, SNP variants showing frequency differences between fast- and slow-growing fish pointed to genomic regions likely involved in growth regulation, and three of them were individually validated through SNP typing. Although different mechanisms appear to explain growth differences among families, general mechanisms seem also to be involved, and thus, results provide a set of useful candidate genes and markers to be evaluated for more efficient growth breeding programs and to perform comparative genomic studies of growth in fish and vertebrates This work was funded by Spanish Ministry of Economy and Competitiveness and European Regional Development Funds (AGL2012-35904), Ministry of Science and Innovation (Consolider Ingenio, Aquagenomics, CSD2007-00002), and Local Government. Xunta de Galicia (GRC2014/010). DR was supported by a FPU fellowship funded by Spanish Ministry of Education, Culture and Sport (AP2012-0254) and a postdoctoral contract funded by the Biotechnology and Biological Science Research Council (BBSRC) grant BB/N024044/1 SI

Background: Zebrafish (Danio rerio) is a model organism that has emerged as a tool for cancer research, cancer being the second most common cause of death after cardiovascular disease for humans in the developed world. Zebrafish is a useful model for xenotransplantation of human cancer cells and toxicity studies of different chemotherapeutic compounds in vivo. Compared to the murine model, the zebrafish model is faster, can be screened using high-throughput methods and has a lower maintenance cost, making it possible and affordable to create personalized therapies. While several methods for cell proliferation determination based on image acquisition and quantification have been developed, some drawbacks still remain. In the xenotransplantation technique, quantification of cellular proliferation in vivo is critical to standardize the process for future preclinical applications of the model. Methods: This study improved the conditions of the xenotransplantation technique - quantification of cellular proliferation in vivo was performed through image processing with our ZFtool software and optimization of temperature in order to standardize the process for a future preclinical applications. ZFtool was developed to establish a base threshold that eliminates embryo auto-fluorescence and measures the area of marked cells (GFP) and the intensity of those cells to define a 'proliferation index'. Results: The analysis of tumor cell proliferation at different temperatures (34 °C and 36 °C) in comparison to in vitro cell proliferation provides of a better proliferation rate, achieved as expected at 36°, a maintenance temperature not demonstrated up to now. The mortality of the embryos remained between 5% and 15%. 5- Fluorouracil was tested for 2 days, dissolved in the incubation medium, in order to quantify the reduction of the tumor mass injected. In almost all of the embryos incubated at 36 °C and incubated with 5-Fluorouracil, there was a significant tumor cell reduction compared with the control group. This was not the case at 34 °C. Conclusions: Our results demonstrate that the proliferation of the injected cells is better at 36 °C and that this temperature is the most suitable for testing chemotherapeutic drugs like the 5-Fluorouracil. Fil: Cabezas-Sainz, Pablo. Universidad de Santiago de Compostela; España Fil: Guerra-Varela, Jorge. Universidad de Santiago de Compostela; España Fil: Carreira, María J.. Universidad de Santiago de Compostela; España Fil: Mariscal, Javier. Universidad de Santiago de Compostela; España Fil: Roel, María. Universidad de Santiago de Compostela; España Fil: Rubiolo, Juan Andrés. Universidad de Santiago de Compostela; España Fil: Sciara, Andres Angel. Universidad Nacional de Rosario; Argentina. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET) - Facultad de Bioquímica y Ciencias Farmacéuticas, ; Argentina Fil: Abal, Miguel. Universidad de Santiago de Compostela; España Fil: Botana, Luis M.. Universidad de Santiago de Compostela; España Fil: López, Rafael. Universidad de Santiago de Compostela; España Fil: Sánchez, Laura. Universidad de Santiago de Compostela; España

In 2012, Tetrodotoxin (TTX) was identified in mussels and linked to the presence of Prorocentrum minimum (P. minimum) in Greece. The connexion between TTX and P. minimum was further studied in this paper. First, the presence of TTX-producer bacteria, Vibrio and Pseudomonas spp, was confirmed in Greek mussels. In addition these samples showed high activity as inhibitors of sodium currents (INa). P. minimum was before associated with neurotoxic symptoms, however, the nature and structure of toxins produced by this dinoflagellate remains unknown. Three P. minimum strains, ccmp1529, ccmp2811 and ccmp2956, growing in different conditions of temperature, salinity and light were used to study the production of toxic compounds. Electrophysiological assays showed no effect of ccmp2811 strain on INa, while ccmp1529 and ccmp2956 strains were able to significantly reduce INa in the same way as TTX. In these samples two new compounds, m/z 265 and m/z 308, were identified and characterized by liquid chromatography tandem high-resolution mass spectrometry. Besides, two TTX-related bacteria, Roseobacter and Vibrio sp, were observed. These results show for the first time that P. minimum produce TTX-like compounds with a similar ion pattern and C9-base to TTX analogues and with the same effect on INa Inés Rodríguez is supported by a fellowship from Subprograma de Formación de Personal Investigador MINECO (AGL2012-40185-CO2-01), Spain. The research leading to these results has received funding from the following FEDER cofunded-grants. From CDTI and Technological Funds, supported by Ministerio de Economía y Competitividad, AGL2012-40185-CO2-01, AGL2014-58210-R, and Consellería de Cultura, Educación e Ordenación Universitaria, GRC2013-016. From CDTI under ISIP Programme, Spain, IDI-20130304 APTAFOOD. From the European Union’s Seventh Framework Programme managed by REA – Research Executive Agency (FP7/2007-2013) under grant agreement 312184 PHARMASEA. SI

Background and Purpose Marine sponges have evolved the capacity to produce a series of very efficient chemicals to combat viruses, bacteria, and eukaryotic organisms. It has been demonstrated that several of these compounds have anti-neoplastic activity. The highly toxic sponge Crambe crambe has been the source of several molecules named crambescidins. Of these, crambescidin-816 has been shown to be cytotoxic for colon carcinoma cells. To further investigate the potential anti-carcinogenic effect of crambescidin-816, we analysed its effect on the transcription of HepG2 cells by microarray analysis followed by experiments guided by the results obtained. Experimental Approach After cytotoxicity determination, a transcriptomic analysis was performed to test the effect of crambescidin-816 on the liver-derived tumour cell HepG2. Based on the results obtained, we analysed the effect of crambescidin-816 on cell-cell adhesion, cell-matrix adhesion, and cell migration by Western blot, confocal microscopy, flow cytometry and transmission electron microscopy. Cytotoxicity and cell migration were also studied in a variety of other cell lines derived from human tumours. Key Results Crambescidin-816 had a cytotoxic effect on all the cell lines studied. It inhibited cell-cell adhesion, interfered with the formation of tight junctions, and cell-matrix adhesion, negatively affecting focal adhesions. It also altered the cytoskeleton dynamics. As a consequence of all these effects on cells crambescidin-816 inhibited cell migration. Conclusions and Implications The results indicate that crambescidin-816 is active against tumour cells and implicate a new mechanism for the anti-tumour effect of this compound.

Yessotoxin at nanomolar concentrations can induce programmed cell death in different model systems. Paraptosis-like cell death induced by YTX in BC3H1 cells, which are insensitive to several caspase inhibitors,has also been reported. This makes yessotoxin of interest in the search of molecules that target cancer cells vulnerabilities when resistance to apoptosis is observed. To better understand the effect of this molecule at the molecular level on tumor cells, we conducted a transcriptomic analysis using 3 human glioma cell lines with different sensitivities to yessotoxin. We show that the toxin induces a deregulation of the lipid metabolism in glioma cells as a consequence of induction of endoplasmic reticulum stress. The endoplasmic reticulum stress in turn arrests the cell cycle and inhibits the protein synthesis. In the three cell lines used we show that YTX induces autophagy, which is involved in cell death. The sensibility of the cell lines used towards autophagic cell death was related to their doubling time, being the cell line with the lowest proliferation rate the most resistant.The involvement of mTOR and BNIP3 in the autophagy induction was also determined.

In this paper, we show the effect of crambescidin-816, -800, and -830 on Saccharomyces cerevisiae viability. We determined that, of the three molecules tested, crambescidin-816 was the most potent. Based on this result, we continued by determining the effect of crambescidin-816 on the cell cycle of this yeast. The compound induced cell cycle arrest in G2/M followed by an increase in cell DNA content and size. When the type of cell death was analyzed, we observed that crambescidin-816 induced apoptosis. The antifungal effect indicates that crambescidins, and mostly crambescidin-816, could serve as a lead compound to fight fungal infections The research leading to these results has received funding from the following FEDER cofunded-grants: From Ministerio de Ciencia y Tecnología, Spain: AGL2009-13581-CO2-01, AGL2012-40485-CO2-01. From Xunta de Galicia, Spain: 10PXIB261254 PR. From the European Union’s Seventh Framework Programme managed by REA—Research Executive Agency (FP7/2007-2013) under grant agreement Nos. 211326—CP (CONffIDENCE), 265896 BAMMBO, 265409 µAQUA, and 262649 BEADS, 315285 Ciguatools and 312184 PharmaSea. From the Atlantic Area Programme (Interreg IVB Trans-national): 2009-1/117 Pharmatlantic SI

International audience; The marine environment offers both economic and scientific potential which are relatively untapped from a biotechnological point of view. These environments whilst harsh are ironically fragile and dependent on a harmonious life form balance. Exploitation of natural resources by exhaustive wild harvesting has obvious negative environmental consequences. From a European industry perspective marine organisms are a largely underutilised resource. This is not due to lack of interest but due to a lack of choice the industry faces for cost competitive, sustainable and environmentally conscientious product alternatives. Knowledge of the biotechnological potential of marine organisms together with the development of sustainable systems for their cultivation, processing and utilisation are essential. In 2010, the European Commission recognised this need and funded a collaborative RTD/SME project under the Framework 7-Knowledge Based Bio-Economy (KBBE) Theme 2 Programme ‘Sustainable culture of marine microorganisms, algae and/or invertebrates for high value added products’. The scope of that project entitled ‘Sustainable Production of Biologically Active Molecules of Marine Based Origin’ (BAMMBO) is outlined. Although the Union is a global leader in many technologies, it faces increasing competition from traditional rivals and emerging economies alike and must therefore improve its innovation performance. For this reason innovation is placed at the heart of a European Horizon 2020 Strategy wherein the challenge is to connect economic performance to eco performance. This article provides a synopsis of the research activities of the BAMMBO project as they fit within the wider scope of sustainable environmentally conscientious marine resource exploitation for high-value biomolecules.

The increasing presence of cyanotoxin producers in several regions of the world is hazardous for humans and animals. Cylindrospermopsin (CYN) is nowadays recognized as a widely distributed freshwater cyanobacterial toxin. This toxin has been shown to induce protein synthesis inhibition as well as inhibition of glutathione synthesis. Given that the liver seems to be the main target of cylindrospermopsin, in this work we used cultures of primary rat hepatocytes to study the type of cell death induced by CYN nanomolar concentrations. The involvement of reactive oxygen species in toxin induced cell death, the relationship between protein synthesis inhibition and toxicity, and the cell endogenous antioxidant response regulation were studied. We show that cylindrospermopsin induces apoptosis in primary rat hepatocytes. At the concentrations used in this work, protein synthesis inhibition and oxidative stress were involved in the cytotoxic effect elicited by the toxin. Finally, activation of the cell antioxidant response was observed at the transcriptional and translational levels. © 2012 American Chemical Society.

// Maria Roel 1 , Juan A. Rubiolo 1 , Jorge Guerra-Varela 2 , Siguara B. L. Silva 3, 4 , Olivier P. Thomas 3, 5 , Pablo Cabezas-Sainz 2 , Laura Sanchez 2 , Rafael Lopez 6 , Luis M. Botana 1 1 Department of Pharmacology, Universidade de Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain 2 Department of Genetics, Universidade de Santiago de Compostela, Campus Lugo, 27002 Lugo, Spain 3 Geoazur, UMR Universite Nice Sophia Antipolis-CNRS-IRD-OCA, 06560 Valbonne, France 4 Laboratoire de Pharmacognosie, UMR CNRS 8076 BioCIS, LabEx LERMIT, Universite Paris-Sud, Faculte de Pharmacie, 92290 Châtenay-Malabry, France 5 School of Chemistry, Marine Biodiscovery, National University of Ireland Galway, SW4 Galway, Ireland 6 Translational Medical Oncology, Health Research Institute of Santiago (IDIS), Complexo Hospitalario Universitario de Santiago de Compostela (SERGAS), 15706 Santiago de Compostela, Spain Correspondence to: Luis M. Botana, email: luis.botana@usc.es Keywords: crambescidins, cell cycle inhibition, apoptosis, zebrafish xenograft model, cancer treatment Received: March 13, 2016 Accepted: September 27, 2016 Published: November 04, 2016 ABSTRACT The marine environment constitutes an extraordinary resource for the discovery of new therapeutic agents. In the present manuscript we studied the effect of 3 different sponge derived guanidine alkaloids, crambescidine-816, -830, and -800. We show that these compounds strongly inhibit tumor cell proliferation by down-regulating cyclin-dependent kinases 2/6 and cyclins D/A expression while up-regulating the cell cyclin-dependent kinase inhibitors -2A, -2D and -1A. We also show that these guanidine compounds disrupt tumor cell adhesion and cytoskeletal integrity promoting the activation of the intrinsic apoptotic signaling, resulting in loss of mitochondrial membrane potential and concomitant caspase-3 cleavage and activation. The crambescidin 816 anti-tumor effect was fnally assayed in a zebrafish xenotransplantation model confirming its potent antitumor activity against colorectal carcinoma in vivo . Considering these results crambescidins could represent promising natural anticancer agents and therapeutic tools.

The first in vitro system for the culture of primary neurons was developed in 1977. Since then, the culture systems for hippocampal and cortical neurons, as well as neuron cell lines, have improved dramatically. Primary neuronal cultures provide a defined environment where neurons can be studied in isolation from other cell types and are a powerful tool for studying cellular and molecular mechanisms of neuronal development, aging, and death. However, the changes that occur in neurons during culture in relation to cell differentiation and medium composition have not been thoroughly characterized. To study the effect of medium change in primary neurons in culture, we performed a transcriptomic analysis using whole mouse genome microarrays, for neurons between 7 and 10 days in vitro after medium change. We show that even though neurons in culture present an expression profile pointing to differentiation with time in culture, medium change induces a transient and partial de-differentiation.

Spirolides are a kind of marine toxins included in the cyclic imine toxin group and produced by the dinoflagellate Alexandrium ostenfeldii. This study shows for the first time a complete and detailed description about the symptoms observed in mice when these toxins were intraperitoneal (i.p.) administered. It is also compared the i.p. toxicity of 13-desmethyl spirolide C (13-desMeC), 13,19-didesMeC (13,19-didesMeC) and 20-methyl spirolide G (20-Me-G) in experiments performed with highly purified toxins. The bioassay indicates that 13-desMeC and 13,19-didesMeC are extremely toxic compounds which have a LD(50) of 27.9μg/kg and 32.2μg/kg, respectively. However, when 20-MeG was i.p administrated with dose up 63.5μg/kg, no deaths were recorded. In order to evaluate the oral toxicity, spirolides were administered by gastric intubation into mice. Then, samples of blood, urine and faeces were collected and analyzed by liquid chromatography-mass spectrometry tandem (LC-MS/MS) technique. Spirolides appear in blood at 15min and in urine after 1h of being toxin administered. In summary, in this paper, it is provided new data about the toxicity, absorption, and excretion of spirolides in mouse. So far, little information is available on this item but necessary for spirolide regulation in the European Union (EU).

Protein phosphatase 2A is the major enzyme that dephosphorylates the serine/threonine residues of proteins in the cytoplasm of animal cells. This phosphatase is most strongly inhibited by okadaic acid. Besides okadaic acid, several other toxins and antibiotics have been shown to inhibit protein phosphatase 2A, including microsystin-LR, calyculin-A, tautomycib, nodularin, cantharidine, and fostriecin. This makes protein phosphatase 2A a valuable tool for detecting and assaying these toxins. High-scale production of active protein phosphatase 2A requires processing kilograms of animal tissue and involves several chromatographic steps. To avoid this, in this work we report the recombinant expression and characterization of the active catalytic subunit α of the protein phosphatase 2A in Trichoplusia ni insect larvae. Larvae were infected with baculovirus carrying the coding sequence for the catalytic subunit α of protein phosphatase 2A under the control of the polyhedrin promoter and containing a poly-His tag in the carboxyl end. The catalytic subunit was identified in the infected larvae extracts, and it was calculated to be present at 250 μg per gram of infected larvae, by western blot. Affinity chromatography was used for protein purification. Protein purity was determined by western blot. The activity of the enzyme, determined by the p-nitrophenyl phosphate method, was 94 μmol/min/mg of purified protein. The catalytic subunit was further characterized by inhibition with okadaic acid and dinophysis toxin 2. The results presented in this work show that this method allows the production of large quantities of the active enzyme cost-effectively. Also, the enzyme activity was stable up to 2 months at −20 °C.

Aims To determine the relative toxicity and effects on the cell cycle of okadaic acid and dinophysistoxin-2 in primary hepatocyte cultures. Main methods Cytotoxicity was determined by the MTT method, caspase-3 activity and lactate dehydrogenase release to the medium. The cell cycle analysis was performed by imaging flow cytometry and the effect of the toxins on cell proliferation was studied by quantitative PCR and confocal microscopy. Key findings We show that dinophysistoxin-2 is less toxic than okadaic acid for primary hepatocytes with a similar difference in potency as that observed in vivo in mice after intraperitoneal injection. Both toxins induced apoptosis with caspase-3 increase. They also inhibited the hepatocytes cell cycle in G1 affecting diploid cells and diploid bi-nucleated cells. In proliferating hepatocytes exposed to the toxins, a decrease of p53 gene expression as well as a lower protein level was detected. Studies of the tubulin cytoskeleton in toxin treated cells, showed nuclear localization of this molecule and a granulated tubulin pattern in the cytoplasm. Significance The results presented in this work show that the difference in toxicity between dinophysistoxin-2 and okadaic acid in cultured primary hepatocytes is the same as that observed in vivo after intraperitoneal injection. Okadaic acid and dinophysistoxin-2 arrest the cell cycle of hepatocytes at G1 even in diploid bi-nucleated cells. p53 and tubulin could be involved in the cell cycle inhibitory effect.

Advances in transgenic technology as well as in the genetics of Alzheimer disease (AD) have allowed the establishment of animal models that reproduce amyloid-beta plaques and neurofibrillary tangles, the main pathological hallmarks of AD. Among these models, 3xTg-AD mice harboring PS1 (M146V), APP (Swe) and tau (P301L) human transgenes provided the model that most closely mimics human AD features. Although cortical cultures from 3xTg-AD mice have been shown to present disturbances in intracellular [Ca(2+)] homeostasis, the development of AD pathology in vitro has not been previously evaluated. In the current work, we determined the temporal profile for amyloid precursor protein, amyloid-beta and tau expression in primary cortical cultures from 3xTg-AD mice. Immunocytochemistry and Western blot analysis showed an increased expression of these proteins as well as several phosphorylated tau isoforms with time in culture. Alterations in calcium homeostasis and cholinergic and glutamatergic responses were also observed early in vitro. Thus, 3x-TgAD cortical neurons in vitro provide an exceptional tool to investigate pharmacological approaches as well as the cellular basis for AD and related diseases.

Background and purpose. Pectenotoxins are macrocyclic lactones found in dinoflagellates of the genus Dinophysis, which induce severe liver damage in mice after i.p. injection. Here, we have looked for the mechanism(s) underlying this hepatotoxicity. Experimental approach. Effects of pectenotoxin (PTX)-1, PTX-2, PTX-2 seco acid (PTX-2SA) and PTX-11 were measured in a hepatocyte cell line with cancer cell characteristics (Clone 9) and in primary cultures of rat hepatocytes. Cell morphology was assessed by confocal microscopy; F- and G-actin were selectively stained and cell viability measured by Alamar Blue fluorescence. Key results. Clone 9 cells and primary hepatocytes showed a marked depolymerization of F-actin with PTX-1, PTX-2 and PTX-11 (1–1000 nM) associated with an increase in G-actin level. However, morphology was only clearly altered in Clone 9 cells. PTX-2SA had no effect on the actin cytoskeleton. Despite the potent F-actin depolymerizing effect, PTX-1, PTX-2 or PTX-11 did not decrease the viability of Clone 9 cells after 24-h treatment. Only prolonged incubation (>48 h) with PTXs induced a fall in viability, and under these conditions, morphology of both Clone 9 and primary hepatocytes was drastically changed. Conclusions and implications. Although the actin cytoskeleton was clearly altered by PTX-1, PTX-2 and PTX-11 in the hepatocyte cell line and primary hepatocytes, morphological assessments indicated a higher sensitivity of the cancer-like cell line to these toxins. However, viability of both cell types was not altered. British Journal of Pharmacology (2008) 155, 934–944; doi:10.1038/bjp.2008.323; published online 8 September 2008

Reactive oxygen species can be important mediators of damage to cell molecules and structures. Besides the endogen antioxidant defences, the antioxidant intake in the diet has an important role in the protection against the development of diseases produced by oxidative damage. Resveratrol is a naturally occurring compound present in many plants some of which are part of the human diet. This molecule has been thoroughly investigated because of its antioxidant and anticarcinogenic properties among others. We investigated whether resveratrol could provide protective antioxidant action in primary rat hepatocyte cultures. Primary rat hepatocytes cultures were exposed to 300 microM tert-butyl hydroperoxide; 25, 50 or 75 microM resveratrol or to 300 microM tert-butyl hydroperoxide plus 25, 50 or 75 microM resveratrol for different time periods. Necrosis was evaluated by lactate dehydrogenase liberation to the medium. Apoptosis was evaluated by caspase 3 activity measurement. Changes in cellular morphology after the different treatments were recorded using bright field microscopy. Inhibition of the reactive oxygen species by resveratrol was studied by confocal microscopy and spectrofluorimetrically. Resveratrol inhibited necrosis induced by tert-butyl hydroperoxide. No apoptosis was observed in any treatment. It also was effective in eliminating reactive oxygen species. At 75 microM, the highest concentration tested, resveratrol became slightly cytotoxic. Our results show that resveratrol protects primary rat hepatocytes in culture from oxidative stress induced cell death. These results suggest that resveratrol could enhance the antioxidant status of hepatic cells.

In recent years, many natural macrolactones have been found that display toxicity against the actin cytoskeleton. Pectenotoxins are macrolactones produced by species of the dinoflagellate genus Dinophysis. They were initially classified within the diarrheic shellfish poisoning group of toxins, because of their co-occurrence and biological origin, but mice toxicity assays demonstrated that pectenotoxins do not induce diarrheic symptoms. Intraperitoneal injection of pectenotoxins into mice produces high hepatotoxicity as the principal symptom, so the liver seems to be their target organ. Up to now, 15 pectenotoxin analogs have been discovered, with different toxicological potencies that are related to their structures. Now, it is generally accepted that the actin cytoskeleton is the principal molecular target of pectenotoxins. Although recent studies have demonstrated that pectenotoxins induce actin filament disruption by a capping effect, other kinds of activity, such as sequestration of actin, cannot be ruled out. All of the active analogs tested triggered disruption of the actin cytoskeleton and displayed potencies that correlated with their toxicity in mice. Moreover, pectenotoxins induce apoptosis to a higher degree in tumor cells than in normal cells of the same tissue. This fact opens the prospect of studying new chemotherapy agents and actin cytoskeleton dynamics with potential clinical applications.

Oxidative stress is recognized as an important factor in the development of liver pathologies. The reactive oxygen species endogenously generated or as a consequence of xenobiotic metabolism are eliminated by enzymatic and nonenzymatic cellular systems. Besides endogen defences, the antioxidant consumption in the diet has an important role in the protection against the development of diseases product of oxidative damage. Resveratrol is a naturally occurring compound which is part of the human diet. This molecule has been shown to have many biological properties, including antioxidant activity. We decided to test if resveratrol could protect primary hepatocytes in culture from oxidative stress damage and if so, to determine if this compound affects the cellular detoxifying systems and their regulation through the Nrf2 transcription factor that regulates the expression of antioxidant and phase II detoxifying enzymes. Cell death by necrosis was detected by measuring the activity of lactate dehydrogenase liberated to the medium. The activities of antioxidant and phase II enzymes were measured using previously described methods. Activation of the Nrf2 transcription factor was studied by confocal microscopy and the Nrf2 and its coding mRNA levels were determined by western blot and quantitative PCR respectively. Resveratrol pre-treatment effectively protected hepatocytes in culture exposed to oxidative stress, increasing the activities of catalase, superoxide dismutase, glutathione peroxidase, NADPH quinone oxidoreductase and glutathione-S-transferase. Resveratrol increases the level of Nrf2 and induces its translocation to the nucleus. Also, it increases the concentration of the coding mRNA for Nrf2. In this work we show that resveratrol could be a useful drug for the protection of liver cells from oxidative stress induced damage.