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1.
An ecotoxicological protocol with caged mussels, Mytilus galloprovincialis, was developed to evaluate the potential impact of an offshore gas platform in the central Adriatic Sea. Reference organisms were collected on a seasonal basis from an unpolluted site and transplanted for four weeks in both the sampling area and to the investigated platform. Chemical analyses of trace metals in mussel tissues were integrated with a multi-biomarker approach for the early detection of biological responses at several cellular targets. Induction of metallothioneins, peroxisomal proliferation and activity of acetylcholinesterase were measured as markers for specific classes of chemicals. Special attention was given to oxyradical metabolism and appearance of oxidative-mediated toxicity to reveal a more general onset of cellular disturbance. In addition to individual antioxidants (superoxide dismutase, catalase, glutathione S-transferases, glutathione reductase, Se-dependent and Se-independent glutathione peroxidases, and levels of total glutathione), the total oxyradical scavenging capacity (TOSC) allowed a quantification of the overall capability to neutralize specific forms of intracellular reactive oxygen species (ROS; i.e. peroxyl and hydroxyl radicals). Cellular damages were evaluated as lysosomal destabilization (membrane stability, accumulation of lipofuscin and neutral lipids), lipid peroxidation products (malondialdehyde) and DNA integrity (strand breaks and micronuclei); the air survival test was finally applied to evaluate the overall physiological condition of mussels. Concentration of trace metals (As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Zn) revealed only limited variations in transplanted mussels during various experimental periods and such changes appeared partly related to natural fluctuations. Among biological responses, variations of antioxidants and lysosomal stability were confirmed as sensitive early warning signals for biological disturbance of both natural and anthropogenic origin. The presented protocol with caged mussels allowed marked biological effects caused by the investigated platform to be excluded, and represented a useful approach that is easy to extend for monitoring the impact of offshore activities in the Adriatic sea.  相似文献   

2.
This study assessed numerous histological parameters as markers of health status in mussels (Mytilus spp.) collected from several locations along a contamination gradient on the River Tamar and two coastal sites on the north and south coast of Cornwall, UK. Twenty-seven health parameters were assessed including the presence of pathogens, inflammatory lesions, non-specific pathologies and reproductive condition. Logistic regression showed that reproductive condition and inflammatory lesions showed changes indicative of a contamination gradient response. Mussel populations further upstream within the Tamar were relatively less developed compared to mussels situated downstream in the estuary. Compared to coastal locations, mussels sampled within the Tamar also exhibited a higher prevalence of inflammatory lesions that increased at locations situated furthest upstream. Similarly, levels of lipofuscin within the kidney epithelium were highest in mussels sampled within the estuary and Whitsand Bay compared to Trebarwith Strand. The most prevalent pathogens observed during this survey included Rickettsia/Chlamydia-like organisms (R/CLO), gill ciliates including Ancistrum mytili, the copepod Mytilicola intestinalis, Ciliophora-like organisms and Marteilia sp. Marteilia sp. was observed in 31% of the mussels sampled from the Cremyll Ferry site. Generally, the range and prevalence of pathogens was highest from the two estuarine locations at Cremyll Ferry and Wilcove. No significant differences were observed between estuarine sampling sites and Whitsand Bay with respect to median epithelial cell height of digestive tubules, however mussels from Trebarwith Strand did exhibit a reduced median epithelial cell height compared to mussels sampled from other sampling sites. Species genotyping was also undertaken during this study in order to consider any histological differences in relation to species. Results are discussed in relation to histopathology health parameters and biological effects monitoring.  相似文献   

3.
The digestive gland and gills of the mussel Crenomytilus grayanus extracted from three locations — (i) sampled from a clean and (ii) polluted site and (iii) transplanted from the nonpolluted to polluted site - were analysed for antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase), total oxyradical scavenging capacity and levels of lipid peroxidation products (malondialdehyde, conjugated dienes and lipofuscin). Perturbation of redox status was found in both digestive gland and gill tissues of mussels living in the polluted area. As the activities of superoxide dismutase and catalase were 1.2–3 times higher, the total oxyradical scavenging capacity was lower by 20–35% and the levels of lipid peroxidation products were 2–7 times higher compared to mussels from the reference site. In transplanted mussels, the lipid peroxidation process in both tissues was significantly stimulated (the level of conjugated dienes was increased 1.7–2.5-fold; malondialdehyde and lipofuscin contents were increased 3.5–5-fold) and the total oxyradical scavenging capacity fell by 50–70%. In addition, the transplantation generally resulted in transient and variable responses of antioxidant enzymes for both tissues. Complex response-behaviour of the antioxidant enzymes strongly points to the necessity of employing a combined approach that takes into account activities of antioxidant enzymes and the total oxyradical scavenging capacity, as well as measurement of oxidative damage (e.g., lipid peroxidation) to evaluate the physiological health of molluscs.  相似文献   

4.
The aim of this study was to examine whether a combination of biochemical, histopathological and toxicogenomic data could be used as a valuable tool for the assessment of biological risk associated with pollutants within the Tamar River and Estuary, S.W. England, U.K. Accordingly, biochemical and histopathological biomarkers (protein carbonyls, lipofuscin, neutral lipids, lysosomal stability [N-acetyl-β-hexosaminidase and neutral red], lysosomal volume, ferric reducing antioxidant power [FRAP] and malonaldehyde [MDA]) and gene expression profiles were assessed in 5 sites from the Tamar River and Estuary (Neal Point, Town Quay, Wilcove, Cremyll Ferry and Whitsand; and a reference site, Trebarwith Strand, N. Cornwall). PAHs were measured in mussel tissue and sediment and metals were measured in mussel tissue only. Data from the biomarkers was integrated into a Mussel Expert System (MES) model to produce a simple assessment of mussel stress. Clear gradients of mussel toxicity were identified by the biomarkers (with the exception of neutral lipids) with the highest impacted animals found furthest up the Tamar, whilst the MES was unable to identify a gradient of effect. Gene expression profiles also indicated a gradient of stress with the greatest number of significantly up- or down- regulated genes found at the uppermost 2 sites. The MES did, however, determine that mussels from all sites, except the reference site, were highly stressed; a conclusion that could not be inferred from the biomarker data alone. It is concluded that the MES is a valuable tool that permits integration and interpretation of complex sets of biomarker data by identifying the biological meaning of biomarker changes.  相似文献   

5.
Specimens of the hydrothermal mussel Bathymodiolus azoricus collected in Menez Gwen hydrothermal vent field (NE Atlantic) during 2002–2003 were examined for feeding patterns variations through three seasons. The fatty acid profile and lipid classes of the mussels were studied, together with the MODIS/AQUA-derived near-surface chlorophyll a to test the hypothesis that surface productivity might be related to the feeding patterns of this species. The lipid levels showed pronounced seasonal fluctuations with the highest values occurring in January and August. Seasonal variations in lipid classes and fatty acid composition of neutral and polar lipids in the mussels are presented. Differences in the fatty acid profile of lipid classes in different seasons suggest that the higher energy requirements in summer and winter were supplied by bacterial biomarkers ω7 MUFA (monounsaturated fatty acids), whereas ω6 PUFA (polyunsaturated fatty acids) and NMI (non-methylene-interrupted) fatty acids predominated during the spring. The MODIS/AQUA data show marked seasonal variability and an anomalous peak during January of 2003, although this cannot be directly linked to lipid composition variation.  相似文献   

6.
Levels of polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene (B[a]P) were at least seven-fold higher in mussels sampled from a polluted site (Loch Leven, in Scotland, UK) compared to a nearby clean reference site (Loch Etive) throughout the year 2000. Levels of DNA strand breaks (alkaline COMET assay) using both gill and digestive gland nuclei were similar at both sites despite the difference in contaminant load (total PAH). In contrast, mussels collected from a reference site (Port Quin, Cornwall, UK) had an increase in DNA strand breaks in digestive gland cells following laboratory exposure to B[a]P-dosed Isochrysis galbana. However, after 14 days high dose (20 ppb-exposed diet) animals had returned to levels similar to the controls. There was no evidence of increased necrosis or apoptosis after treatments. The results from these two studies suggest that an adaptive response may prevent ongoing DNA damage in mussels exposed to high levels of B[a]P and PAH contamination.  相似文献   

7.
A multiple biomarker approach was adopted in a seasonal study carried out in the Lagoon of Venice, with the double aim of evaluating the natural and anthropic stresses influencing the biological responses of mussel (Mytilus galloprovincialis) and of assessing the effects due to spatial rather than temporal variations.Biochemical (aldehyde dehydrogenase and catalase activities), cellular (neutral red retention time) and physiological (survival in air and condition index) biomarkers were determined in mussels collected in four differently impacted lagoon areas.Multivariate analysis showed that samples were distributed mainly according to temperature and four seasonal groups were identified. The combination of spatial and temporal information enabled us to distinguish physiological variations due to natural causes from those due to anthropic stress, and to identify the sampling period when several biomarkers are less influenced by both natural and endogenous factors.  相似文献   

8.
Water and particles from three sites located in Halifax Harbour, near and further away from combined municipal sewage effluents (CMSE) were analysed for parental and alkylated polycyclic aromatic hydrocarbons (par and alkPAH). Bioavailability of PAH was compared for inter-tidal mussels collected at the same sites in April and November. The PAH fingerprint determined over 9 sampling times covering a period of 19 months differed more between phases (water and particles) and seasons, than between sites. In the spring, more alkPAH associated with diesel and gasoline were detected in the soluble phase, along with more bioaccumulation of alkPAH in inter-tidal mussels. A broader number of parPAH were detected in mussels collected in the fall. The mean sum of dissolved alkPAH concentrations was higher in water at the site closer to raw CMSE than at the other two sites and particles of that site. However, lowest bioconcentration factors (BCF) were determined in mussels of this more contaminated site. Similar biota-particle accumulation factors (BPAF) were determined for parPAH in mussels from the three sites, all lower than the BCF of alkPAH. The study indicates that sewage treatment plants will reduce the amount of parPAH especially larger than fluoranthene and pyrene from being deposited in the harbour; that alk naphthalenes and fluorenes present in water will continue to be discharged; that the disturbance of sediments can make particle-bound PAH available to mussels.  相似文献   

9.
A number of biochemical markers and a physiological index were measured in mussels, Mytilus galloprovincialis, transplanted or native to five different contaminated sites in the lagoon of Venice. Mussels from Pellestrina, a reference site in the adjacent Adriatic Sea, were transplanted for 6 weeks to areas of the lagoon where indigenous mussels were also collected. As biochemical indices, superoxide dismutase (SOD), catalase, aldehyde dehydrogenase (ADH) and NADPH cytochrome c reductase (NADPHcred) were measured in mussel digestive gland; survival in air as a physiological index was also determined. Biomarker responses varied among sites and between indigenous and transplanted animals. Significant induction of catalase and SOD was shown in animals transplanted to the urban sites of Salute and Chioggia, respectively. In indigenous mussels, induction of SOD and NADPHcred was seen in animals from the polluted site of Treporti and the heavily contaminated industrial area of Marghera. The overall biochemical data indicate significantly higher activity for ADH in transplanted animals in comparison with indigenous ones which, in contrast, present an increase in SOD. As regard survival in air, control mussels did not seem to be healthier in comparison either with transplanted or indigenous ones, suggesting that pollution has no effect on this parameter.  相似文献   

10.
The neutral red lysosomal retention assay (NRR) of the haemocytes, and the acetylcholinesterase activity (AChE) in the haemolymph, the digestive gland, the gills and the mantle/gonad complex have been evaluated on mussels Mytilus galloprovincialis collected from Thermaikos and Strymonikos gulfs (northern Greece) in June and October 2001. The validity of performing the above core biomarkers is supported, firstly by their ability to respond to different pollution levels and, secondly, by the significant linear correlation among them. The evaluation of the micronuclei frequency (MN) has been performed in gill tissue and haemocytes of the same mussels and, according to the results, it needs more research in order its use as stress indices to be validated. In addition, the first results on cAMP levels in the gills, the mantle/gonad complex and the digestive gland, whose concentrations correlated to both, NRR and AChE introduce this signal transduction molecule as a new, promising biomarker.  相似文献   

11.
Mytilus edulis digestive gland microsomes were prepared from indigenous populations sampled from a clean reference site (Port Quin) and an urban-industrial contaminated site (Blackpool) in the UK. Samples were collected in March/April, May, August and December 1998. Western blot analysis was performed using polyclonal antibodies to fish CYP1A and rat CYP2E using partially purified M. edulis CYP as a positive control, to aid identification. CYP1A- and CYP2E-immunopositive protein levels showed different site-specific seasonal variation with higher levels of CYP2E determined in May (P < 0.05). At both sites, lower levels of CYP1A-immunopositive protein but not CYP2E-immunopositive protein were observed in the samples collected in December (P < 0.05). This correlated with lower levels of nuclear DNA damage (Comet assay expressed as per cent tail DNA) observed in December compared to August (P < 0.05).  相似文献   

12.
Expanding industrial activities in the Arctic require an urgent assessment of the toxicity of chemicals at low temperatures. Organisms acclimatized to low temperature exhibit specific adaptations. For example, the amount of unsaturated lipids is increased to maintain the fluidity of the cell membranes. It has been hypothesized that such temperature-induced alterations in membrane lipid composition may affect the stability of lysosomal and cell membranes in the common mussel, Mytilus edulis, an organism exposed to seasonal temperature extremes. As mussels may be exposed to petroleum compounds along industrialized coastlines, we tested the combined effects of exposure to low temperature and the petroleum compound, phenanthrene, on haemocyte membrane stability. Test animals, acclimated to either 0 or 10 degrees C, were exposed to phenanthrene (0 = control or 500 micrograms l-1) and haemocytes were examined using the neutral red retention assay (lysosomal stability) and a fluorescence assay (cell membrane stability). At 0 degree C, lysosomal and cell membranes from uncontaminated mussels were destabilized compared with 10 degrees C (P = 0.0005). No significant effects (P > 0.05) of phenanthrene were detected at either temperature. Possible mechanisms underlying membrane destabilization include a weaker physical resistance of the membrane due to a higher amount of unsaturated lipids, a potentially higher level of reactive oxygen radicals at low temperature and the higher susceptibility of unsaturated lipids to oxidative stress. More work is required to better understand the consequences of this membrane destabilization at low temperature on the susceptibility of the organism to pollutants.  相似文献   

13.
Mytilus edulis were collected from a reference site (Port Quin) and an urban/industrial contaminated site (New Brighton) in the UK during June 1999. Levels of PCBs (sigma7 congeners) and CB-138 were determined to be, respectively, 21 fold and 16 fold higher in the mussel digestive glands from New Brighton. Levels of CYPIA-immunopositive protein were 1.5 fold higher (P < 0.05) at the polluted site but the levels of DNA strand breaks were 1.3 fold higher (P<0.05) at the reference site. Mussels from Port Quin were placed in cages at both sites and both transplanted and indigenous populations sampled in September (13 weeks). Mussels transplanted from the reference site to the industrial site, reported elevated levels of CYP1A-immunopositive protein (1.4 fold; P < 0.05) and higher levels of DNA damage (1.2 fold; P < 0.05) compared to caged populations at the reference site and a PCB loading similar to the populations from the polluted site. Moreover, transplanted mussels had DNA damage 1.8 fold greater (P < 0.05) than indigenous mussels at the transplant site. These changes were small but significant when compared to the observed temporal changes in the indigenous populations.  相似文献   

14.
A field study was carried out in the Lagoon of Venice (north-east Italy) with the aim of evaluating the potential use of lysosomal destabilisation as a biomarker of anthropogenic stress in the autochthonous mussel Mytilus galloprovincialis. Two different approaches were adopted in biomonitoring six sites in the Lagoon, evaluating indigenous populations of mussels and organisms transplanted from a reference site and checked at several points in time. Lysosomal membrane stability was investigated by means of two tests: neutral red retention assay (NRRA) for evaluating haemocyte lysosomes and lysosomal latency test (LLT) for digestive cell lysosomes. Results indicate that the lysosomal response measured in haemocytes according to NRRA is a more valuable biomarker of anthropogenic stress in the framework both of passive and active biomonitoring in marine coastal environments.  相似文献   

15.
It has been shown that the rate of protein synthesis is significantly decreased in various tissues of mussels gathered from a coastal area, characterised by a high level of pollution, when compared with animals collected in the reference unpolluted area. Such a decrease may represent a general stress index. Additional biological parameters, such as amino acid uptake and RNA synthesis, are similarly decreased in the mussels collected from the polluted area.Moreover, it has been demonstrated that in the digestive gland of the animals sampled from the heavy metal polluted area the level of low molecular weight thionein-like Cu-binding proteins is three times higher than in the digestive gland of the control mussels. The increase in the level of metallothionein-like proteins in the digestive gland of the mussels appears to represent a specific stress index directly related to the presence in the sea water of high concentrations of heavy metals.  相似文献   

16.
The aim of this study was to investigate the cellular and biochemical response of mussels, Mytilus galloprovincialis, transplanted from a relatively pristine site to a polluted one and vice versa in the Lagoon of Venice (northeast of Italy) and to apply auto-metallography, a rapid and sensitive histochemical technique, to determine the bio-available fraction of heavy metals accumulated in the body tissues of organisms. Animal digestive glands have been used for morphological analyses (lysosomal volume, surface and numerical density, mean epithelial thickness, mean diverticular and luminar radius), autometallographical black silver deposits quantification and biochemical assays (superoxide dismutase and catalase activity). Furthermore, heavy metal content was determined by atomic absorption spectrophotometry (AAS) using standard procedures. The overall results indicate a direct influence of the environment in the thinning of the digestive cells and in the increasing number of lysosomes in mussels from the more polluted site. These data are in agreement with the metal content in digestive cell lysosomes as determined by autometallography, whereas AAS measurements show less significant differences.  相似文献   

17.
Diets of male and female West Coast rock lobster Jasus lalandii in South Africa were compared across a large size range of 10–85 mm carapace length (CL). The diets of male rock lobsters were compared between two different depths, different seasons, across the moult cycle, and among eight sites along the South-Western Cape coast. There was no significant difference in diet between male and female rock lobsters for any of the size-classes examined. Male rock lobsters showed large differences in diet between small and large size-classes. The diet of small lobsters (<75mm CL) consisted of a wide range of species, which included, in order of importance, coralline algae, barnacles Notomegabalanus algicola, sponges and ribbed mussels Aulacomya ater. However, prey items rich in inorganic material were not dominant in their diet, as had been predicted. By contrast, large rock lobsters (>80mm CL) fed on few species, and fish and ribbed mussels were their most abundant prey items. There were some dietary differences between individuals captured at 20 m and those collected at 50 m, but these differences were less marked than between the two sampling sites (the Knol and Olifantsbos). There was seasonal variation in diet at the Dassen Island and Olifantsbos sites. Cannibalism was highest during the moulting periods. Gut fullness varied seasonally at Dassen Island, and was consistently high at Olifantsbos. However, the proportion of the population feeding showed marked seasonal trends at both sites, tracking the commercial catch per unit effort of rock lobster. Ribbed mussels were a ubiquitous and dominant component of the diet at the eight sites sampled. However, south of Dassen Island, black mussels Choromytilus meridionalis were scarce in the diet of rock lobster and sponges predominated. Gut fullness was lowest at the northernmost sites.  相似文献   

18.
The effects of contaminants on the biochemical parameters of the intensively farmed mussel Perna perna, are unknown. The aim of this study was to compare biochemical responses in mussels held in clean and contaminated sites in Santa Catarina Island, Brazil. Mussels were transplanted from a farming area, Ratones Grande Island (RGI), to two contaminated sites, Itacorubi (ITAC) and Hercílio Luz Bridge (HLB). A reference group was kept at RGI. After 150 and 180 days of exposure, the digestive glands of the mussels were analyzed for catalase, glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferase (GST) activities. No changes were observed in the catalase activity, in both periods. Low G6PDH activity was observed in mussels transplanted for 150 days at the ITAC site. Increased GST activity was observed in mussels from ITAC and HLG sites after 180 days. These responses are probably related to the augmented discharges of domestic effluents associated with elevated rainfall index.  相似文献   

19.
Sub-cellular perturbations in the lysosomal compartment of molluscan haemocytes were examined in mussels (Perna viridis), collected along a pollution gradient. The neutral red technique was validated using a well defined contamination gradient among indigenous populations from five stations along Tolo Harbour, Hong Kong. Condition indices (shell length:dry tissue wt) and tissue metal concentrations were also measured in an attempt to identify a relationship between contamination level and adverse physiological effects. Correlations were found between lysosomal retention time and condition along the pollution gradient. There were significant differences between mussels collected from stations on offshore islands and those collected from inner harbour sites (p < 0.05). There was, however, little correlation between metal concentrations and retention time or condition (p > 0.05).  相似文献   

20.
Studies were performed on the common mussel, M. edulis L., to determine whether copper (Cu) exposure can affect the extent to which digestive cell proteins are oxidised and whether such oxidative damage is mediated by free radicals. Three age groups of mussels were exposed for 6 -days to environmentally realistic concentrations of Cu and then digestive gland homogenates were examined for evidence of protein carbonyl formation. Significant increases in carbonyls relative to untreated control mussels were seen for the youngest (2–4 year-old) and oldest (≥ 10 year-old) mussels only after exposure for 6 days, followed by recovery from exposure for a further 6 days. Untreated mussels also showed an age-related difference in protein oxidation, with a significantly lower concentration in the youngest animals (2–4 year olds). Copper did not affect the levels of modified tryptophan or tyrosine residues or the extent of total lipid peroxidation in digestive gland homogenate. Significant depletion of total vitamin E (a-tocopherol) was seen only in young and medium-aged mussels following exposure for 6 days. The levels of protein carbonyl groups were increased in digestive cell cytosol and lighter lysosomes but not in heavier lysosomes or digestive gland microsomes following 5 days exposure to Cu. Dihydrohodamine-123 was converted to fluorescent rhodamine-123 following sequestration into digestive cell lysosomes. The results suggest a link between the lysosomal sequestration of copper, a concomitant increase in the production of oxyradicals and the potential for intracellular oxidative damage, as well as an increased capacity for oxidative damage in older animals.  相似文献   

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