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1.
Dev Comp Immunol ; 67: 404-412, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27567602

RESUMEN

Sphingomyelin-binding proteins of the lysenin family were originally identified in earthworms belonging to the genus Eisenia comprised of at least two distinct species, E. andrei and E. fetida, until recently considered subspecies or morphotypes of E. foetida (sic). In the present study the presence of lysenin and lysenin-related protein 2 (LRP-2, known also as fetidin) was detected in coelomocytes retrieved from all investigated adult specimens of E. andrei, and E. fetida. They were accompanied by LRP-3 and LRP-1 in some specimens of E. andrei and E. fetida, respectively. Lysenins were not observed in a third composting lumbricid species, Dendrobaena veneta, which served as a convenient negative reference for techniques and procedures used in the study. The pore-forming potential of soluble and cellular fractions of coelomic fluid was studied towards sheep red blood cells and sphingomyelin-rich liposomes. After experimental depletion the potential was restored in parallel with restoration of chloragocyte-derived eleocytes in both E. andrei and E. fetida.


Asunto(s)
Hemólisis , Oligoquetos/inmunología , Fagocitos/inmunología , Proteínas/metabolismo , Toxinas Biológicas/metabolismo , Animales , Células Cultivadas , Espectrometría de Masas , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Unión Proteica , Proteínas/genética , Especificidad de la Especie , Esfingomielinas/metabolismo , Toxinas Biológicas/genética
2.
Folia Biol (Krakow) ; 64(2): 121-30, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29537194

RESUMEN

Stressed earthworms expel coelomic fluid containing several vital cellular and soluble components, thus their post-stress recovery has adaptive value. The present manuscript describes the recovery rates of coelomocytes (amoebocytes and eleocytes) and two fluorophores (riboflavin and 4-methylumbelliferyl ß-D-glucuronide, MUG) after experimental extrusion by electrostimulation. Analyses were conducted at time points (from 0.5 hour to 7 weeks) by a combination of cell counts, spectrofluorimetric measurements of riboflavin and MUG, and fluorescence microscopy. Coelomic fluid retrieved 30 minutes after extrusion contained <10% of the baseline levels of amoebocytes, eleocytes and riboflavin; the depleted levels of these variables were fully restored after 3, 5, and 7 weeks post-extrusion, respectively. Restored eleocytes were richer in riboflavin than the eleocytes of worms electrostimulated at t0. MUG was less severely depleted (to 49% of baseline) than riboflavin, and was restored to the initial level within 1 week post-extrusion. This indicates that MUG, unlike riboflavin, resides mainly within non-coelomocyte cellular location(s); moreover, this fluorophore may be a useful molecular marker for distinguishing even immunologically-compromised E. andrei from closely related composting species.


Asunto(s)
Oligoquetos/citología , Animales , Líquidos Corporales/citología , Colorantes Fluorescentes
3.
Folia Biol (Krakow) ; 64(4): 275-284, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29809366

RESUMEN

Lumbricid earthworms are often exposed to polluted soil. They are also commonly subjected to various stimuli and attacks by predators that induce extrusion of coelomocyte-containing coelomic fluid and/or the loss of body segments followed by the renewal of immune-competent cells and regeneration of tissues/organs. The aim of our investigations was to test the effects of exposure of the earthworm Eisenia andrei to cadmium-polluted soil, combined with electrostimulation-induced depletion of coelomocytes (i.e. amoebocytes and chloragocyte-derived eleocytes) or the surgical amputation of posterior segments, on earthworm maturation, reproductive output, and regenerative processes. Experimental worms were maintained up to 7 weeks either in unpolluted soil or in soil spiked with cadmium chloride (500 mg/kg air-dried soil). In juvenile worms, sexual maturation (measured by clitellum formation) was delayed and cocoon production was inhibited in Cd-exposed worms. Coelomocytes were significantly depleted by electrostimulation and the kinetics of their recovery was similar in worms kept in clean and cadmium polluted soils, in both exposure conditions amoebocyte recovery was faster than recovery of riboflavin-storing eleocytes. In adult worms, soil cadmium exposure inhibited reproduction but, at macroanatomical level, had a negligible effect on regeneration of amputated posterior segments, visible only on histological cross-sections.


Asunto(s)
Cadmio/toxicidad , Oligoquetos/efectos de los fármacos , Regeneración/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Oligoquetos/citología , Oligoquetos/fisiología , Maduración Sexual/efectos de los fármacos
4.
Ecotoxicology ; 25(2): 267-78, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26581474

RESUMEN

Silver nanoparticles (Ag NPs) have been used in numerous consumer products and may enter the soil through the land application of biosolids. However, little is known about the relationship between Ag NP exposure and their bioavailability for soil organisms. This study aims at comparing the uptake and elimination kinetics of Ag upon exposures to different Ag forms (NPs and ionic Ag (as AgNO3)) in the isopod Porcellionides pruinosus. Isopods were exposed to contaminated Lufa 2.2 soil or alder leaves as food. Uptake and elimination rate constants for soil exposure did not significantly differ between Ag NPs and ionic Ag at 30 and 60 mg Ag/kg. For dietary exposure, the uptake rate constant was up to 5 times higher for Ag NPs than for AgNO3, but this was related to feeding activity and exposure concentrations, while no difference in the elimination rate constants was found. When comparing both routes, dietary exposure resulted in lower Ag uptake rate constants but elimination rate constants did not differ. A fast Ag uptake was observed from both routes and most of the Ag taken up seemed not to be eliminated. Synchrotron X-ray fluorescence showed Ag in the S-cells of the hepatopancreas, thus supporting the observations from the kinetic experiment (i.e. low elimination). In addition, our results show that isopods have an extremely high Ag accumulation capacity, suggesting the presence of an efficient Ag storage compartment.


Asunto(s)
Isópodos/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Nitrato de Plata/toxicidad , Plata/toxicidad , Contaminantes del Suelo/toxicidad , Animales , Femenino , Masculino , Portugal , Toxicocinética
5.
Nat Commun ; 6: 7869, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26241769

RESUMEN

All higher plants produce polyphenols, for defence against above-ground herbivory. These polyphenols also influence the soil micro- and macro-fauna that break down plant leaf litter. Polyphenols therefore indirectly affect the fluxes of soil nutrients and, ultimately, carbon turnover and ecosystem functioning in soils. It is unknown how earthworms, the major component of animal biomass in many soils, cope with high-polyphenol diets. Here, we show that earthworms possess a class of unique surface-active metabolites in their gut, which we term 'drilodefensins'. These compounds counteract the inhibitory effects of polyphenols on earthworm gut enzymes, and high-polyphenol diets increase drilodefensin concentrations in both laboratory and field populations. This shows that drilodefensins protect earthworms from the harmful effects of ingested polyphenols. We have identified the key mechanism for adaptation to a dietary challenge in an animal group that has a major role in organic matter recycling in soils worldwide.


Asunto(s)
Oligoquetos/metabolismo , Polifenoles/metabolismo , Animales , Avena , Dieta , Tracto Gastrointestinal/metabolismo , Herbivoria , Quercus , Tensoactivos/metabolismo
6.
Dev Comp Immunol ; 52(2): 269-79, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25863277

RESUMEN

Earthworm decerebration causes temporary inhibition of reproduction which is mediated by certain brain-derived neurohormones; thus, cocoon production is an apposite supravital marker of neurosecretory center functional recovery during brain regeneration. The core aim of the present study was to investigate aspects of the interactions of nervous and immune systems during brain regeneration in adult Dendrobaena veneta (Annelida; Oligochaeta). Surgical brain extirpation was combined, either with (i) maintenance of immune-competent coelomic cells (coelomocytes) achieved by surgery on prilocaine-anesthetized worms or (ii) prior extrusion of fluid-suspended coelomocytes by electrostimulation. Both brain renewal and cocoon output recovery were significantly faster in earthworms with relatively undisturbed coelomocyte counts compared with individuals where coelomocyte counts had been experimentally depleted. These observations provide empirical evidence that coelomocytes and/or coelomocyte-derived factors (e.g. riboflavin) participate in brain regeneration and, by implication, that there is close functional synergy between earthworm neural and immune systems.


Asunto(s)
Encéfalo/fisiología , Regeneración Nerviosa/inmunología , Oligoquetos/fisiología , Animales , Encéfalo/anatomía & histología , Oligoquetos/anatomía & histología , Reproducción
7.
Environ Toxicol Chem ; 34(10): 2263-70, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25917164

RESUMEN

Current bioavailability models, such as the free ion activity model and biotic ligand model, explicitly consider that metal exposure will be mainly to the dissolved metal in ionic form. With the rise of nanotechnology products and the increasing release of metal-based nanoparticles (NPs) to the environment, such models may increasingly be applied to support risk assessment. It is not immediately clear, however, whether the assumption of metal ion exposure will be relevant for NPs. Using an established approach of oral gluing, a toxicokinetics study was conducted to investigate the routes of silver nanoparticles (AgNPs) and Ag(+) ion uptake in the soil-dwelling earthworm Lumbricus rubellus. The results indicated that a significant part of the Ag uptake in the earthworms is through oral/gut uptake for both Ag(+) ions and NPs. Thus, sealing the mouth reduced Ag uptake by between 40% and 75%. An X-ray analysis of the internal distribution of Ag in transverse sections confirmed the presence of increased Ag concentrations in exposed earthworm tissues. For the AgNPs but not the Ag(+) ions, high concentrations were associated with the gut wall, liver-like chloragogenous tissue, and nephridia, which suggest a pathway for AgNP uptake, detoxification, and excretion via these organs. Overall, the results indicate that Ag in the ionic and NP forms is assimilated and internally distributed in earthworms and that this uptake occurs predominantly via the gut epithelium and less so via the body wall. The importance of oral exposure questions the application of current metal bioavailability models, which implicitly consider that the dominant route of exposure is via the soil solution, for bioavailability assessment and modeling of metal-based NPs.


Asunto(s)
Nanopartículas del Metal/toxicidad , Oligoquetos/efectos de los fármacos , Plata/análisis , Contaminantes del Suelo/farmacocinética , Animales , Disponibilidad Biológica , Iones/química , Nanopartículas del Metal/química , Oligoquetos/metabolismo , Medición de Riesgo , Plata/metabolismo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Distribución Tisular , Espectroscopía de Absorción de Rayos X
8.
Ecotoxicology ; 24(2): 239-61, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25516483

RESUMEN

Initiatives to support the sustainable development of the nanotechnology sector have led to rapid growth in research on the environmental fate, hazards and risk of engineered nanoparticles (ENP). As the field has matured over the last 10 years, a detailed picture of the best methods to track potential forms of exposure, their uptake routes and best methods to identify and track internal fate and distributions following assimilation into organisms has begun to emerge. Here we summarise the current state of the field, focussing particularly on metal and metal oxide ENPs. Studies to date have shown that ENPs undergo a range of physical and chemical transformations in the environment to the extent that exposures to pristine well dispersed materials will occur only rarely in nature. Methods to track assimilation and internal distributions must, therefore, be capable of detecting these modified forms. The uptake mechanisms involved in ENP assimilation may include a range of trans-cellular trafficking and distribution pathways, which can be followed by passage to intracellular compartments. To trace toxicokinetics and distributions, analytical and imaging approaches are available to determine rates, states and forms. When used hierarchically, these tools can map ENP distributions to specific target organs, cell types and organelles, such as endosomes, caveolae and lysosomes and assess speciation states. The first decade of ENP ecotoxicology research, thus, points to an emerging paradigm where exposure is to transformed materials transported into tissues and cells via passive and active pathways within which they can be assimilated and therein identified using a tiered analytical and imaging approach.


Asunto(s)
Ecotoxicología/métodos , Contaminantes Ambientales/metabolismo , Peces/metabolismo , Invertebrados/metabolismo , Nanopartículas del Metal , Nanotubos de Carbono , Plantas/metabolismo , Animales , Monitoreo del Ambiente , Contaminantes Ambientales/farmacocinética , Óxidos/metabolismo , Óxidos/farmacocinética
9.
Biol Lett ; 10(9)2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25252836

RESUMEN

Molecular genetic methods can distinguish divergent evolutionary lineages in what previously appeared to be single species, but it is not always clear what functional differences exist between such cryptic species. We used a metabolomic approach to profile biochemical phenotype (metabotype) differences between two putative cryptic species of the earthworm Lumbricus rubellus. There were no straightforward metabolite biomarkers of lineage, i.e. no metabolites that were always at higher concentration in one lineage. Multivariate methods, however, identified a small number of metabolites that together helped distinguish the lineages, including uncommon metabolites such as Nε-trimethyllysine, which is not usually found at high concentrations. This approach could be useful for characterizing functional trait differences, especially as it is applicable to essentially any species group, irrespective of its genome sequencing status.


Asunto(s)
Metabolómica/métodos , Oligoquetos/clasificación , Oligoquetos/metabolismo , Animales , Lisina/análogos & derivados , Lisina/metabolismo , Espectroscopía de Resonancia Magnética , Análisis Multivariante , Fenotipo , Especificidad de la Especie
10.
Ecotoxicol Environ Saf ; 74(4): 719-26, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21040972

RESUMEN

Lumbricus rubellus is a cosmopolitan earthworm devoid of riboflavin-storing eleocytes; its immune competent coelomocytes are predominantly amoebocytes. Our aim was to determine whether amoebocyte cytometrics in L. rubellus are robust biomarkers for innate immunological responses to environmental pollutants. Investigations were conducted on populations inhabiting three unpolluted and five metalliferous (mainly Pb+Zn+Cd) habitats in the UK and Poland. Inter-population differences in worm mass and amoebocyte numbers did not consistently reflect soil or tissue metal concentrations. Flow cytometry indicated that autofluorescence of the amoebocytes differs between cells from the unpolluted and metal-polluted worms, and pinocytosis of neutral red by amoebocytes was lower (especially at 15 versus 60 min incubation) in worms from the polluted Poland site compared with the reference population. To conclude, amoebocyte cytometrics and functionality are potentially useful for environmental diagnostics; deployment is contingent on better understanding potential confounders.


Asunto(s)
Metales/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Suelo/química , Animales , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Ambiente , Monitoreo del Ambiente , Citometría de Flujo , Sustancias Peligrosas/análisis , Sustancias Peligrosas/toxicidad , Plomo/análisis , Plomo/toxicidad , Metales/análisis , Níquel/análisis , Níquel/toxicidad , Oligoquetos/citología , Oligoquetos/fisiología , Polonia , Contaminantes del Suelo/análisis , Reino Unido , Zinc/análisis , Zinc/toxicidad
11.
Chemosphere ; 81(2): 199-205, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20633922

RESUMEN

A 6-week reciprocal transfer laboratory exposure experiment was conducted with two populations of the epigeic earthworm Dendrodrilus rubidus; one population inhabited a site approx. 200 m downwind of an active Ni smelter co-contaminated with Ni and Cu (3648 and 977 microg g(-1)d.w., respectively), the other inhabited uncontaminated soil. Worms transferred from unpolluted to Ni/Cu-polluted soil lost body mass (62%); they also had reduced (70%) total coelomocyte number, including autofluorescent eleocytes, and had significantly decreased (92%) riboflavin-derived fluorescence emission measured at 525 nm. Coelomocyte counts were low, and 525 nm emission was negligible in worms maintained on their native Ni/Cu soil. Earthworms and their coelomocytes were unaffected when transferred from Ni/Cu-polluted soil to unpolluted soil. In conclusion, exposing worms to stress-inducing factors, including metal pollution, alters the riboflavin status within the immune-competent cells of D. rubidus, but it requires further in vivo studies to establish whether the reduction in the fluorescence signal is predominantly due to depletion of riboflavin-containing eleocytes, or to riboflavin quenching, or to enzymatic conversion (and thus depletion) of stored riboflavin into its functional immune-potentiating flavin derivatives, FMN and FAD. The flavin budget of D. rubidus coelomocytes recovered by a reproducible extrusion procedure is a potentially useful biomarker for assessing sublethal stress in this early colonizer of disturbed soils.


Asunto(s)
Níquel/toxicidad , Oligoquetos/metabolismo , Riboflavina/metabolismo , Contaminantes del Suelo/toxicidad , Animales , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Sistema Digestivo/efectos de los fármacos , Sistema Digestivo/metabolismo , Citometría de Flujo , Níquel/análisis , Níquel/metabolismo , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Espectrometría de Fluorescencia
12.
Environ Pollut ; 158(9): 2793-808, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20619942

RESUMEN

Diverse anthropogenic activities often lead to the accumulation of inorganic and organic residues in topsoils. Biota living in close contact with contaminated soils may experience stress at different levels of biological organisation throughout the continuum from the molecular-genetic to ecological and community levels. To date, the relationship between changes at the molecular (mRNA expression) and biochemical/physiological levels evoked by exposures to chemical compounds has been partially established in a limited number of terrestrial invertebrate species. Recently, the advent of a family of transcriptomic tools (e.g. Real-time PCR, Subtractive Suppressive Hybridization, Expressed Sequence Tag sequencing, pyro-sequencing technologies, Microarray chips), together with supporting informatic and statistical procedures, have permitted the robust analyses of global gene expression changes within an ecotoxicological context. This review focuses on how transcriptomics is enlightening our understanding of the molecular-genetic responses of three contrasting terrestrial macroinvertebrate taxa (nematodes, earthworms, and springtails) to inorganics, organics, and agrochemicals.


Asunto(s)
Artrópodos/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Nematodos/efectos de los fármacos , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Agroquímicos/toxicidad , Animales , Artrópodos/genética , Artrópodos/metabolismo , Perfilación de la Expresión Génica , Metales/toxicidad , Nematodos/genética , Nematodos/metabolismo , Oligoquetos/genética , Oligoquetos/metabolismo , Hidrocarburos Policíclicos Aromáticos/toxicidad
13.
BMC Syst Biol ; 4: 32, 2010 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-20331876

RESUMEN

BACKGROUND: Physiologically based modelling using DEBtox (dynamic energy budget in toxicology) and transcriptional profiling were used in Caenorhabditis elegans to identify how physiological modes of action, as indicated by effects on system level resource allocation were associated with changes in gene expression following exposure to three toxic chemicals: cadmium, fluoranthene (FA) and atrazine (AZ). RESULTS: For Cd, the physiological mode of action as indicated by DEBtox model fitting was an effect on energy assimilation from food, suggesting that the transcriptional response to exposure should be dominated by changes in the expression of transcripts associated with energy metabolism and the mitochondria. While evidence for effect on genes associated with energy production were seen, an ontological analysis also indicated an effect of Cd exposure on DNA integrity and transcriptional activity. DEBtox modelling showed an effect of FA on costs for growth and reproduction (i.e. for production of new and differentiated biomass). The microarray analysis supported this effect, showing an effect of FA on protein integrity and turnover that would be expected to have consequences for rates of somatic growth. For AZ, the physiological mode of action predicted by DEBtox was increased cost for maintenance. The transcriptional analysis demonstrated that this increase resulted from effects on DNA integrity as indicated by changes in the expression of genes chromosomal repair. CONCLUSIONS: Our results have established that outputs from process based models and transcriptomics analyses can help to link mechanisms of action of toxic chemicals with resulting demographic effects. Such complimentary analyses can assist in the categorisation of chemicals for risk assessment purposes.


Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Animales , Atrazina/toxicidad , Cadmio/química , Cadmio/toxicidad , Análisis por Conglomerados , Fluorenos/toxicidad , Genoma , Análisis de los Mínimos Cuadrados , Modelos Biológicos , Análisis de Secuencia por Matrices de Oligonucleótidos , Análisis de Componente Principal , Transcripción Genética
14.
Environ Sci Technol ; 43(17): 6822-9, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19764255

RESUMEN

Predicting metal bioaccumulation and toxicity in soil organisms is complicated by site-specific biotic and abiotic parameters. In this study we exploited tissue fractionation and digestion techniques, combined with X-ray absorption spectroscopy (XAS), to investigate the whole-body and subcellular distributions, ligand affinities, and coordination chemistry of accumulated Pb and Zn in field populations of the epigeic earthworm Lumbricus rubellus inhabiting three contrasting metalliferous and two unpolluted soils. Our main findings were (i) earthworms were resident in soils with concentrations of Pb and Zn ranging from 1200 to 27,000 mg kg(-1) and 200 to 34,000 mg kg(-1), respectively; (ii) Pb and Zn primarily accumulated in the posterior alimentary canal in nonsoluble subcellular fractions of earthworms; (iii) site-specific differences in the tissue and subcellular partitioning profiles of populations were observed, with earthworms from a calcareous site partitioning proportionally more Pb to their anterior body segments and Zn to the chloragosome-rich subcellular fraction than their acidic-soil inhabiting counterparts; (iv) XAS indicated that the interpopulation differences in metal partitioning between organs were not accompanied by qualitative differences in ligand-binding speciation, because crystalline phosphate-containing pyromorphite was a predominant chemical species in the whole-worm tissues of all mine soil residents. Differences in metal (Pb, Zn) partitioning at both organ and cellular levels displayed by field populations with protracted histories of metal exposures may reflect theirinnate ecophysiological responses to essential edaphic variables, such as Ca2+ status. These observations are highly significant in the challenging exercise of interpreting holistic biomarker data delivered by "omic" technologies.


Asunto(s)
Plomo/análisis , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/análisis , Zinc/análisis , Absorciometría de Fotón , Animales , Fraccionamiento Celular , Plomo/farmacocinética , Plomo/toxicidad , Microscopía Electrónica de Transmisión , Oligoquetos/metabolismo , Oligoquetos/ultraestructura , Contaminantes del Suelo/farmacocinética , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/ultraestructura , Sincrotrones , Distribución Tisular , Zinc/farmacocinética , Zinc/toxicidad
15.
Environ Pollut ; 157(11): 3042-50, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19541398

RESUMEN

The effect of Pb + Zn on coelomocyte riboflavin content in the epigeic earthworm Dendrodrilus rubidus inhabiting three metalliferous soils and one reference soil was measured by flow cytometry and spectrofluorimetry. A reciprocal polluted<-->unpolluted worm transfer experiment (4-week exposure) was also performed. High proportions of autofluorescent eleocytes were counted in worms from all localities, but intense riboflavin-derived autofluorescence was detectable only in reference worm eleocytes. Other findings were: (i) fluorophore(s) other than riboflavin is/are responsible for eleocyte autofluorescence in residents of metalliferous soils; (ii) riboflavin content was reduced in the eleocytes of worms transferred from unpolluted to metal-polluted soil; (iii) the riboflavin content of D. rubidus eleocytes is a promising biomarker of exposure; (iv) COII mitochondrial genotyping revealed that the reference population is genetically distinct from the three mine populations; (v) metal exposure rather than genotype is probably the main determinant of inter-population differences in eleocyte riboflavin status.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales/toxicidad , Oligoquetos/efectos de los fármacos , Oligoquetos/metabolismo , Riboflavina/metabolismo , Contaminantes del Suelo/toxicidad , Animales , Biomarcadores/análisis , Contaminación Ambiental/análisis , Genotipo , Oligoquetos/química , Oligoquetos/genética , Oligoquetos/crecimiento & desarrollo , Riboflavina/análisis
16.
Environ Pollut ; 157(8-9): 2459-69, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19346039

RESUMEN

The earthworm Lumbricus rubellus (Hoffmeister, 1843) is a terrestrial pollution sentinel. Enzyme activity and transcription of phase II detoxification superfamily glutathione transferases (GST) is known to respond in earthworms after soil toxin exposure, suggesting GST as a candidate molecular-based pollution biomarker. This study combined sub-proteomics, bioinformatics and biochemical assay to characterise the L. rubellus GST complement as pre-requisite to initialise assessment of the applicability of GST as a biomarker. L. rubellus possesses a range of GSTs related to known classes, with evidence of tissue-specific synthesis. Two affinity-purified GSTs dominating GST protein synthesis (Sigma and Pi class) were cloned, expressed and characterised for enzyme activity with various substrates. Electrospray ionisation mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS) following SDS-PAGE were superior in retaining subunit stability relative to two-dimensional gel electrophoresis (2-DE). This study provides greater understanding of Phase II detoxification GST superfamily status of an important environmental pollution sentinel organism.


Asunto(s)
Monitoreo del Ambiente/métodos , Glutatión Transferasa/metabolismo , Oligoquetos/metabolismo , Contaminantes del Suelo/toxicidad , Animales , Biomarcadores/metabolismo , Fase II de la Desintoxicación Metabólica , Oligoquetos/efectos de los fármacos
17.
BMC Genomics ; 9: 266, 2008 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-18522720

RESUMEN

BACKGROUND: Natural contamination and anthropogenic pollution of soils are likely to be major determinants of functioning and survival of keystone invertebrate taxa. Soil animals will have both evolutionary adaptation and genetically programmed responses to these toxic chemicals, but mechanistic understanding of such is sparse. The clitellate annelid Lumbricus rubellus is a model organism for soil health testing, but genetic data have been lacking. RESULTS: We generated a 17,000 sequence expressed sequence tag dataset, defining ~8,100 different putative genes, and built an 8,000-element transcriptome microarray for L. rubellus. Strikingly, less than half the putative genes (43%) were assigned annotations from the gene ontology (GO) system; this reflects the phylogenetic uniqueness of earthworms compared to the well-annotated model animals. The microarray was used to identify adult- and juvenile-specific transcript profiles in untreated animals and to determine dose-response transcription profiles following exposure to three xenobiotics from different chemical classes: inorganic (the metal cadmium), organic (the polycyclic aromatic hydrocarbon fluoranthene), and agrochemical (the herbicide atrazine). Analysis of these profiles revealed compound-specific fingerprints which identify the molecular responses of this annelid to each contaminant. The data and analyses are available in an integrated database, LumbriBASE. CONCLUSION: L. rubellus has a complex response to contaminant exposure, but this can be efficiently analysed using molecular methods, revealing unique response profiles for different classes of effector. These profiles may assist in the development of novel monitoring or bioremediation protocols, as well as in understanding the ecosystem effects of exposure.


Asunto(s)
Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Oligoquetos/efectos de los fármacos , Oligoquetos/genética , Contaminantes del Suelo/toxicidad , Suelo , Xenobióticos/toxicidad , Animales , Atrazina/toxicidad , Cadmio/toxicidad , Exposición a Riesgos Ambientales , Etiquetas de Secuencia Expresada , Fluorenos/toxicidad , Biblioteca de Genes , Herbicidas/toxicidad , Oligoquetos/crecimiento & desarrollo , Análisis de Secuencia por Matrices de Oligonucleótidos , Reproducibilidad de los Resultados , Contaminantes del Suelo/química , Xenobióticos/química
18.
BMC Biol ; 6: 25, 2008 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-18522721

RESUMEN

BACKGROUND: New methods are needed for research into non-model organisms, to monitor the effects of toxic disruption at both the molecular and functional organism level. We exposed earthworms (Lumbricus rubellus Hoffmeister) to sub-lethal levels of copper (10-480 mg/kg soil) for 70 days as a real-world situation, and monitored both molecular (cDNA transcript microarrays and nuclear magnetic resonance-based metabolic profiling: metabolomics) and ecological/functional endpoints (reproduction rate and weight change, which have direct relevance to population-level impacts). RESULTS: Both of the molecular endpoints, metabolomics and transcriptomics, were highly sensitive, with clear copper-induced differences even at levels below those that caused a reduction in reproductive parameters. The microarray and metabolomic data provided evidence that the copper exposure led to a disruption of energy metabolism: transcripts of enzymes from oxidative phosphorylation were significantly over-represented, and increases in transcripts of carbohydrate metabolising enzymes (maltase-glucoamylase, mannosidase) had corresponding decreases in small-molecule metabolites (glucose, mannose). Treating both enzymes and metabolites as functional cohorts led to clear inferences about changes in energetic metabolism (carbohydrate use and oxidative phosphorylation), which would not have been possible by taking a 'biomarker' approach to data analysis. CONCLUSION: Multiple post-genomic techniques can be combined to provide mechanistic information about the toxic effects of chemical contaminants, even for non-model organisms with few additional mechanistic toxicological data. With 70-day no-observed-effect and lowest-observed-effect concentrations (NOEC and LOEC) of 10 and 40 mg kg-1 for metabolomic and microarray profiles, copper is shown to interfere with energy metabolism in an important soil organism at an ecologically and functionally relevant level.


Asunto(s)
Cobre/toxicidad , Oligoquetos/metabolismo , Contaminantes del Suelo/toxicidad , Animales , Análisis por Conglomerados , Ecosistema , Histidina/metabolismo , Metabolismo de los Lípidos , Espectroscopía de Resonancia Magnética , Metabolismo , Oligoquetos/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos
19.
Environ Sci Technol ; 41(12): 4458-64, 2007 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-17626452

RESUMEN

In this study, we addressed the question of whether an omic approach could genuinely be useful for biomarker profile analysis across different field sites with different physicochemical characteristics. We collected earthworms (Lumbricus rubellus) from seven sites with very different levels of metal contamination and prevailing soil type and analyzed tissue extracts by 1H nuclear magnetic resonance spectroscopy. Pattern recognition analysis of the data showed that both site- and contaminant-specific effects on the metabolic profiles could be discerned. Zinc was identified as the probable major contaminant causing a metabolic change in the earthworms. Individual sites could be resolved on the basis of NMR spectral profiles by principal component analysis; these site differences may also have been caused by additional abiotic factors such as soil pH. Despite an inevitable degree of confounding between site and contaminant concentrations, it was possible to identify metabolites which were correlated with zinc across all different sites. This study therefore acts as a proof of principle for the use of NMR-based metabolic profiling as a diagnostic tool for ecotoxicological research in polluted field soils.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales/metabolismo , Oligoquetos/metabolismo , Contaminantes del Suelo/análisis , Animales , Biomarcadores/análisis , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Contaminantes del Suelo/metabolismo , Reino Unido , Zinc/análisis , Zinc/metabolismo
20.
Environ Sci Technol ; 41(4): 1085-96, 2007 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-17593704

RESUMEN

Risk assessment of metal-contaminated habitats based on responses in the field is complicated by the evolution of local, metal-resistant ecotypes. The unpredictability of occurrence of genetically determined adaptive traits, in terms of site-specific geochemistry, a population's inferred exposure history, and in the physiology of resistance, exacerbates the problem. Micro-evolutionary events warrant the attention of ecotoxicologists because they undermine the application of the bedrock of toxicology, the dose-response curve, to in situ field assessments. Here we survey the evidence for the existence of genetically differentiated, metal-resistant, invertebrate populations; we also describe some of the molecular mechanisms underpinning the adaptations. Quantitative changes in tissue-metal partitioning, and in the molecular and cellular responses (biomarkers)to alterations in internal bioreactive metal pools, are widely accepted as indicators of toxicity and/or exposure in free-living organisms. Both can be modulated by resistance. The understanding that all genomes are intrinsicallyflexible, with subtle sequence changes in promoter regions or epigenetic adjustments conferring significant phenotypic consequences, is deemed highly relevant. Equally relevant is the systems biology insight that genes and proteins are woven into networks. We advocate that biomarker studies should work toward assimilating and exploiting these biological realities through monitoring the activities of suites of genes (transcriptomics) and their expressed products (proteomics), as well as profiling the metabolite signatures of individuals (metabolomics) and by using neutral genetic markers to genotype populations. Ecotoxicology requires robust tools that recognize the imprint of evolution on the constitution of field populations, as well as sufficient mechanistic understanding of the molecular-genetic observations to interpret them in meaningful environmental diagnostic ways.


Asunto(s)
Adaptación Fisiológica , Invertebrados/efectos de los fármacos , Metales/toxicidad , Animales , Evolución Biológica , Biomarcadores , Tolerancia a Medicamentos , Ecología , Invertebrados/fisiología
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