1,1,1-trichloro-2,2-bis (p-chlorophenyl)-ethane (DDT) and 1,1-Dichloro-2,2-bis (p, p'-chlorophenyl) ethylene (DDE) as endocrine disruptors in human and wildlife: A possible implication of mitochondria

1,1,1-trichloro-2,2-bis (p-chlorophenyl)-ethane (DDT) and its main metabolite 1,1-Dichloro-2,2-bis (p, p'-chlorophenyl) ethylene (DDE) act as endocrine disruptors in humans and wildlife. Immunomodulatory functions have also been attributed to both xenobiotics. DDT was banned in the 1970s due to its toxicity, but it is still produced and used for indoor residual spraying with disease vector control purposes. Due to their persistence and lipophilic properties, DDT and DDE can bioaccumulate through the food chain, being stored in organisms' adipose depots. Their endocrine disruptor function is mediated by agonist or antagonist interaction with nuclear receptors. Present review aimed to provide an overview of how DDT and DDE exposure impacts reproductive and immune systems with estrogen-disrupting action in humans and wildlife. Studies showing DDT and DDE impact on mitochondrial function and apoptosis pathway will also be reviewed, suggesting the hypothesis of direct action on mitochondrial steroid receptors.

The influence of salinity on sodium lauryl sulfate toxicity in Mytilus galloprovincialis

The influence of salinity on the effects of sodium lauryl sulfate (SLS) was evaluated using the Mediterranean mussel Mytilus galloprovincialis, exposed for 28 days to SLS (control-0.0 and 4.0 mg/L) under three salinity levels (Control-30, 25 and 35). The effects were monitored using biomarkers related to metabolism and energy reserves, defence mechanisms (antioxidant and biotransformation enzymes) and cellular damage. The results revealed that non-contaminated mussels tended to maintain their metabolic capacity regardless of salinity, without activation of antioxidant defence strategies. On the contrary, although contaminated mussels presented decreased metabolic capacity at salinities 25 and 35, they were able to activate their antioxidant mechanisms, preventing cellular damage. Overall, the present findings indicate that SLS, especially under stressful salinity levels, might potentially jeopardize population survival and reproduction success since reduced metabolism and alterations on mussels' antioxidant mechanisms will impair their biochemical and, consequently, physiological performance.

Response of aquatic macroinvertebrates communities to multiple anthropogenic stressors in a lowland tributary river

In the current study the response of aquatic macroinvertebrate communities to multiple anthropogenic stressors in a typical lowland river that crosses pristine sectors situated toward headwaters, as well as densely populated urban areas was assessed. We wished to develop an effective bioassay procedure for assessing water and sediment quality in lotic ecosystems from Romania with the aid of macroinvertebrate organisms correlated with physico-chemical parameters and pollutants in both dissolved fractions and material bonded to sediment. A fast scanning approach of the river, from springs to the mouth, was employed. We found significant changes in physico-chemical parameters along a longitudinal gradient, the highest values being registered within the urban area and heavily agriculturally developed areas. The macroinvertebrates showed affinities for certain abiotic factors, emphasising their potential use for future studies as reliable ecological indicators, shaped by a synergic combination of urban effects and magnitude of type of land use.

Cassia fistula ameliorates chronic toxicity of cypermethrin in Catla catla

Protective effects of Cassia fistula, in Catla catla exposed to synthetic pyrethroid cypermethrin were evaluated. Fish, after chronic exposure to environmentally relevant sub-lethal concentration 0.41 μg/l of the pesticide were assessed for antioxidant activity, histopathological and ultrastructural alterations. Significant (p < 0.05) decrease in the activities of antioxidants such as CAT, SOD, GST, GSH was registered, whereas LPO level got elevated. Histological damage depicted necrosis, epithelial hypertrophy, hyperplasia and fusion of secondary lamellae and changes in gill vasculature. Histopathological alteration index was employed for the semi quantitative evaluation of the degree of tissue change (DTC). Transmission electron microscopy displayed swollen and distorted mitochondria, damaged chloride cells and necrosis. Dietary supplementation of Cassia fistula bark extract significantly (p < 0.05) improved the antioxidant activity, reduced lipid peroxidation and prevented histopathological alterations. The findings suggest that sub-lethal concentration of cypermethrin is toxic to fish. The study also draws attention towards potential of plant derived antioxidants in mitigating pesticide induced toxic effects.

An investigation on protective effects of the new killed vaccine against nervous necrosis virus (NNV) using histopathology and immunohistochemistry approach on the brain and eye tissues of Acipenser stellatus Pallas 1771

The objective of this study was to analyze the efficiency of the killed vaccine against nervous necrosis virus on Acipenser stellutus. Heat inactivated VNN vaccine was administrated in 7 g juveniles of Acipenser stellutus as a laboratory model and it was included in three different adjuvants that were used as injection and immersion forms with different doses. Ten groups consisting of 30 A. stellutus fish in each group (group 1-4 with 3 replications, others with no replicate) were divided totally into 18 aquariums. Two steps of vaccination were done with a one-month interval and after that, all treatments and control groups were challenged by the virulent VNN virus. The mortality rate of immersion and injection groups were 12.9% and 19.8% respectively, compared to 100% mortality in the control group. Histopathology and immunohistochemistry findings were evaluated. According to the mortality rate one month after challenging, a low range mortality of 12.5% was seen in group 2 with no pathological lesion and negative IHC test in the brain and eye tissues, whereas 100% of the control group (unvaccinated group) died with severe vacuolation in the brain and eye tissues and also positive IHC test. The correlation assay between these results concluded that the immersion form with 75% of aquatic-specific Montanide IMS 1312 Seppic adjuvant made better immunization with no pathological sign or forming the complex of antigen-antibody in IHC assay. These findings are important because of the impossibility of injection in the larval stage and also due to the occurrence of the disease in the first stage of sturgeon life which could cause high mortality in susceptible fish in the larval stage.

Behavior evaluation of rainbow trout (Oncorhynchus mykiss) following temperature and ammonia alterations

In the study, we assessed how acute changes in water temperature and dissolved ammonia concentration can affect the swimming behavior pattern of rainbow trout (Oncorhynchus mykiss). The behavior was analyzed in three different stages: 1) increase stage, (where temperature and ammonia concentration increase during this step, respectively); 2) unchanged stage, (where levels of both factors do not change during this stage); 3) reduction stage, (where ammonia concentration and temperature during this stage are reduced), respectively. The results showed that both factors significantly changed the swimming pattern of the rainbow trout. There were significant differences in swimming parameters (distance from the center, swimming speed, total movement and the average of angular changes of movement) of treated fish in the comparison between treatments, and with the control group. The changes in the swimming pattern of fish in response to physicochemical parameters of water were confirmed to be a good tool in ecotoxicological studies.

Studying microplastics: Lessons from evaluated literature on animal model organisms and experimental approaches

Although we are witnesses of an increase in the number of studies examining the exposure/effects of microplastics (MPs) on different organisms, there are many unknowns. This review aims to: (i) analyze current studies devoted to investigating the exposure/effects of MPs on animals; (ii) provide some basic knowledge about different model organisms and experimental approaches used in studying MPs; and to (iii) convey directions for future studies. We have summarized data from 500 studies published from January 2011 to May 2020, about different aspects of model organisms (taxonomic group of organisms, type of ecosystem they inhabit, life-stage, sex, tissue and/or organ) and experimental design (laboratory/field, ingestion/bioaccumulation/effect). We also discuss and try to encourage investigation of some less studied organisms (terrestrial and freshwater species, among groups including Annelida, Nematoda, Echinodermata, Cnidaria, Rotifera, birds, amphibians, reptiles), and aspects of MP pollution (long-term field studies, comparative studies examining life stages, sexes, laboratory and field work). We hope that the information presented in this review will serve as a good starting point and will provide useful guidelines for researchers during the process of deciding on the model organism and study designs for investigating MPs.

Double-edged sword: Fluoxetine and ibuprofen as development jeopardizers and apoptosis' inducers in common toad, Bufo bufo, tadpoles

Nowadays the presence of pharmaceuticals in the environment is a real problem. Ending up in aquatic environments they negatively affect non-target organisms. Considering the limited studies on the negative effects of pharmaceuticals in amphibians, a better understanding of the mechanisms underlying the sub-lethal effects of drug mixtures in wildlife is an urgent call. Representing particularly vulnerable organisms currently at risk of extinction, amphibians are perfect non-target organisms to explore the consequences of pharmaceuticals during sensitive life-stages. To address this existing research gap, the effects of two drugs, the antidepressant fluoxetine and the anti-inflammatory ibuprofen, as well as their combination has been studied. Tadpoles of Bufo bufo were exposed for seven days to two environmentally realistic concentrations of fluoxetine, ibuprofen and their mixture. The development, behavior and erythron profile were then evaluated as endpoints of exposure response. Both drugs negatively affected tadpoles' growth and development by significantly delayed their time to metamorphosis and reduced body weight. Behaviors were also impaired with a significant increase of unresponsiveness to different stimuli. Mutagenic analysis of blood revealed a significant increase in the frequency of cellular and nuclear abnormalities. Given the complexity of systems and functions affected, our work confirms the toxicological potential of fluoxetine and ibuprofen in B. bufo tadpoles by emphasizing their role as tadpole development delayers and erythrocyte apoptosis-inducers. To our knowledge, this is the first study trying to elucidate the potentially toxic effects of a mixture of an antidepressant with a non-steroidal anti-inflammatory drug using bullfrog tadpole as model organism. Both drugs interacted in impairing development and fitness in tadpoles, which might affect long-term species perpetuation and population dynamic. More in-depth research is needed to elucidate the nature of interaction and molecular mechanisms of mixed pharmaceutical compounds on non-targeted organisms.

Androgenic activation, impairment of the monoaminergic system and altered behavior in zebrafish larvae exposed to environmental concentrations of fenitrothion

Fenitrothion is an organophosphorus insecticide usually found in aquatic ecosystems at concentrations in the range of low ng/L. In this manuscript we show that 24 h exposure to environmental concentrations of fenitrothion, from ng/L to low μg/L, altered basal locomotor activity, visual-motor response and acoustic/vibrational escape response of zebrafish larvae. Furthermore, fenitrothion and expression of gap43a, gfap, atp2b1a, and mbp exhibited a significant non-monotonic concentration-response relationship. Once determined that environmental concentrations of fenitrothion were neurotoxic for zebrafish larvae, a computational analysis identified potential protein targets of this compound. Some of the predictions, including interactions with acetylcholinesterase, monoamine-oxidases and androgen receptor (AR), were experimentally validated. Binding to AR was the most suitable candidate for molecular initiating event, as indicated by both the up-regulation of cyp19a1b and sult2st3 and the non-monotonic relationship found between fenitrothion and the observed responses. Finally, when the integrity of the monoaminergic system was evaluated, altered levels of L-DOPA, DOPAC, HVA and 5-HIAA were found, as well as a significant up-regulation of slc18a2 expression at the lowest concentrations of fenitrothion. These data strongly suggest that concentrations of fenitrothion commonly found in aquatic ecosystems present a significant environmental risk for fish communities.

Zebrafish as a Screening Model to Study the Single and Joint Effects of Antibiotics

The overuse of antibiotics combined with the limitation of wastewater facilities has resulted in drug residue accumulation in the natural environment. Thus, in recent years, the presence of antibiotic residues in the environment has raised concerns over the potential harmful effects on ecosystems and human health. The in vivo studies represent an essential step to study the potential impact induced by pharmaceutical exposure. Due to the limitations of traditional vertebrate model systems, zebrafish (Danio rerio) has recently emerged as a promising animal model to study the toxic effects of drugs and their therapeutic efficacy. The present review summarizes the recent advances made on the toxicity of seven representative classes of antibiotics, namely aminoglycosides, β-lactams, macrolides, quinolones, sulfonamides, tetracyclines and polyether antibiotics, in zebrafish, as well as the combined effects of antibiotic mixtures, to date. Despite a significant amount of the literature describing the impact of single antibiotic exposure, little information exists on the effects of antibiotic mixtures using zebrafish as an animal model. Most of the research papers on this topic have focused on antibiotic toxicity in zebrafish across different developmental stages rather than on their efficacy assessment.

Monitoring of Environmental Hg Occurrence in Tunisian Coastal Areas

Total mercury (Hg) was determined in 450 environmental samples (seawater, sediment plant and fish) from five Mahdia coastal areas (Tunisia). Tolerable Weekly Intake% (TWI) values, according to the European Food Safety Authority (EFSA), were calculated based on the average metal concentration in fish and the average weekly fish consumption rate. Hg was accumulated mainly in fish and in Posidonia oceanica leaves. Hg in sediment ranged from 1.88 μg/kg dry weight (d.w.) to 7.48 μg/kg d.w., while it was between 0.32 μg/kg and 0.19 μg/kg in seawaters. Our study showed high concentration in Posidonia oceanica in S3 (plant = 16.76 ± 4.48 μg/kg d.w.) as compared to those in S4 sites (plant = 5.33 ± 0.05 μg/kg d.w.). Concentrations for S. aurata and S. salpa in the Rejiche area exceeded the EC 1881/2006 legislation with values of 1.9 mg/kg and 2.5 mg/kg, respectively, and consumers may be exposed to high concentrations of Hg that exceeds the EFSA. The results showed that the fish species should be constantly monitored due to their TWI% of 154.5% for S. aurata and 209.8% S. salpa respectively.

Effects of Desiccation on Metamorphic Climax in Bombina variegata: Changes in Levels and Patterns of Oxidative Stress Parameters

Simple Summary

Global warming alters patterns of precipitation and drought, which are important factors in the survival of amphibian populations. Metamorphosis is affected by environmental changes; this is especially true of metamorphic climax, the crucial stage of amphibian development that is accompanied by significant morphological, physiological and behavioral adaptations necessary for the transition to a terrestrial habitat. This study investigated naturally occurring changes in the cellular oxidative status (antioxidant system and oxidative damage) of yellow-bellied toad larvae during this phase, and how exposure to exogenous factors such as desiccation affected them. Our results revealed clear changes in the antioxidant system’s (AOS) response and the levels of oxidative damage during metamorphic climax, with the highest response and damage observed at the end stage. Decreasing water levels during larval development altered the components of the AOS and increased oxidative damage, resulting in increased oxidative stress. The knowledge gained from this study could contribute to a better understanding of the oxidative stress that larvae experience during this critical stage of development, and the consequences of global warming—such as water loss—on amphibians.

Abstract

In this paper, we examined how the oxidative status (antioxidant system and oxidative damage) of Bombina variegata larvae changed during the metamorphic climax (Gosner stages: 42—beginning, 44—middle and 46—end) and compared the patterns and levels of oxidative stress parameters between individuals developing under constant water availability (control) and those developing under decreasing water availability (desiccation group). Our results revealed that larvae developing under decreasing water availability exhibited increased oxidative damage in the middle and end stages. This was followed by lower levels of glutathione in stages 44 and 46, as well as lower values of catalase, glutathione peroxidase, glutathione S-transferase and sulfhydryl groups in stage 46 (all in relation to control animals). Comparison between stages 42, 44 and 46 within treatments showed that individuals in the last stage demonstrated the highest intensities of lipid oxidative damage in both the control and desiccation groups. As for the parameters of the antioxidant system, control individuals displayed greater variety in response to changes induced by metamorphic climax than individuals exposed to desiccation treatment. The overall decrease in water availability during development led to increased oxidative stress and modifications in the pattern of AOS response to changes induced by metamorphic climax in larvae of B. variegata.

Chemically and Green Synthesized ZnO Nanoparticles Alter Key Immunological Molecules in Common Carp (Cyprinus carpio) Skin Mucus

This study was conducted to compare the effects of commercially available (C) and green synthesized (GS) Zinc oxide nanoparticles (ZnO-NPs) on immunological responses of common carp (Cyprinus carpio) skin mucus. GS ZnO-NPs were generated using Thymus pubescent and characterized by UV–vis diffuse reflectance spectroscopy (DRS), Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX). Fish (n = 150) were randomly allocated into five groups in triplicate and received a waterborne concentration of 0% (control), 25%, and 50% of LC50 96 h of commercially available (C1 and C2) and green synthesized ZnO-NPs (GS1 and GS2) for 21 days. Results from XRD displayed ZnO-NPs with 58 nm in size and UV-vis DRS, EDX, and FT-IR analysis showed that some functional groups from plant extract bonded to the surface of NPs. The SEM images showed that ZnO-NPs have conical morphology. Acute toxicity study showed a higher dose of LC50_96h for green synthesized ZnO-NPs (78.9 mg.L⁻¹) compared to the commercial source (59.95 mg.L⁻¹). The highest activity of lysozyme and alternative complement activity (ACH50) were found in control and GS1 groups. A significant decrease in alkaline phosphatase activity (ALP) was found in C1 and C2 groups compared to other treatments. Protease activity (P) was significantly decreased in the C2 group compared to the control and GS groups. Total immunoglobulin (total Ig) content was the highest in the control. In addition, total Ig in the GS1 group was higher than GS2. The exposure to ZnO-NPs lowered total protein content in all experimental groups when compared to control. Present findings revealed lower induced immunosuppressive effects by green synthesized ZnO-NPs on key parameters of fish skin mucus.

Nephroprotective effect of Emblica officinalis fruit extract against malachite green toxicity in piscine model: Ultrastructure and oxidative stress study

Malachite green (MG) is a multi-application dye with raised concern as aquatic toxicant. Cyprinus carpio fingerlings were exposed to MG and simultaneously fed with Emblica officinalis (EO) fruit extract to mitigate the MG induced nephrotoxicity. MG exposure developed depressed activity of antioxidant enzymes such as catalase, superoxide dismutase, glutathione-s-transferase, and reduced glutathione, while levels of malondialdehyde got significantly (p < .05) elevated after 60 days MG exposure. H&E staining revealed increased intracellular space, vacuolation, fluid-filled spaces, damaged brush border lining of proximal convoluted tubule (PCT), focal necrosis, nuclear transformations and shrunken glomerulus. Further, Transmission electron microscope study detailed structural cytotoxicity with the appearance of the heterochromatic nucleus, electron-dense lysosomal bodies, damaged brush border lining of PCT, and necrosis; glomerulus exhibited erythrocyte infiltration and fused pedicels of podocyte. While, EO extract supplemented diet culminated in the restoration of the renal cytoarchitecture and significantly (p < .05) enhanced activity of antioxidant enzymes.

Physiological and metabolic approach of plastic additive effects: Immune cells responses

Human and wildlife are continually exposed to a wide range of compounds and substances, which reach the body through the air, water, food, or personal care products. Plasticizers are compounds added to plastics and can be released to the environment under certain conditions. Toxicological studies have concluded that plasticizers, phthalates, and bisphenols are endocrine disruptors, alter the endocrine system and functioning of the immune system and metabolic process. A functional immune response indicates favourable living conditions for an organism; conversely, a weak immune response could reveal a degraded environment that requires organisms to adapt. There is growing concern about the presence of plastic debris in the environment. In this review, the current knowledge of the action of plasticizers on leukocyte cells will be itemized. We also point out critically the role of some nuclear and membrane receptors as key players in the action of plasticizers on cells possess immune function. We discuss the role of erythrocytes within the immune responses and the alteration caused by plasticizers. Finally, we highlight data evidencing mitochondrial dysfunctions triggered by plasticizing toxic action, which can lead to immunosuppression.

Effect of allicin on antioxidant defense system, and immune response after carbofuran exposure in Nile tilapia, Oreochromis niloticus

In this work, allicin was evaluated as an immunostimulant and antioxidant agent preventing Nile tilapia; Oreochromis niloticus against carbofuran toxicity. Fish (60 ± 8 g) were allocated to five groups; the first group (control), the second group was fed 1 g/kg allicin-supplemented diets without carbofuran intoxication, the third group exposed to 1/10 LC₅₀ carbofuran (0.246 mg/L). While the fourth, and fifth groups were fed allicin supplemented diet at concentration of 0.5 and 1 g/kg diet, respectively, and exposed to carbofuran at the same concentration similar to the one of the third group. After 30 days, fish exposed to carbofuran showed high ALT, AST, ALP, cholesterol, glucose, cortisol, uric acid, and creatinine levels. However, serum AChE, total proteins, immunoglobulins, and lysozyme activity were markedly (P ≤ 0.05) reduced in carbofuran exposed tilapia fish. Moreover, malondialdehyde (MDA) level was significantly increased in liver, and kidneys tissues of carbofuran exposed fish. Whereas, catalase (CAT) activity, superoxide dismutase (SOD), and total antioxidant capacity (TAC) were decreased (P ≤ 0.05) significantly in both liver, and kidneys tissues after exposure to carbofuran. Interestingly, tilapia fish treated with carbofuran (0.246 mg/L) and fed (0.5 and 1 g/kg diet) allicin in both the 4th & 5th groups, respectively, decreased serum biochemical parameters; and hepatorenal (MDA) levels, as well as increased AChE, immunological profile, and oxidative stress biomarkers. The results suggested that co- administration of allicin at the high dose is more capable of improving the biochemical, and immunological parameters, and tissue antioxidant responses of carbofuran treated fish.

Oregano (Origanum vulgare) Extract Enhances Zebrafish (Danio rerio) Growth Performance, Serum and Mucus Innate Immune Responses and Resistance against Aeromonas hydrophila Challenge

This study evaluated the dietary effects of an ultrasound-assisted extract of Origanum vulgare on the growth, antioxidant and immune responses (serum and mucosal) and resistance of zebrafish (Danio rerio) against Aeromonas hydrophila. Four hundred and forty adult zebrafish were distributed into 12 tanks and fed 4 experimental diets including 0% (control), 0.5% (M1), 1% (M2) and 2% (M3) of the extract per kg-1 diet for eight weeks. Fish were then challenged with A. hydrophila and mortality was recorded for 10 days. Results revealed that the extract exerted potent effects on growth parameters of weight gain and specific growth rate. The feed conversion ratio was significantly lower in fish fed extract-incorporated diets. O. vulgare extract improved antioxidant and immune responses, resulting in less sensitivity to oxidative stress and a higher survival rate when challenged with A. hydrophila. Overall, the greatest effects were observed in individuals with 1% dietary inclusion of the extract. These results suggest that the extract from the plant Origanum vulgare possesses a great potential to be used in the aquaculture industry and that zebrafish is an appropriate model for nutrition studies.

MicroRNA-mediated stress response in bivalve species

Bivalve mollusks are important aquatic organisms, which are used for biological monitoring because of their abundance, ubiquitous nature, and abilities to adapt to different environments. MicroRNAs (miRNAs) are small noncoding RNAs, which typically silence the expression of target genes; however, certain miRNAs directly or indirectly upregulate their target genes. They are rapidly modulated and play an essential role in shaping the response of organisms to stresses. Based on the regulatory function and rapid alteration of miRNAs, they could act as biomarkers for biotic and abiotic stress, including environmental stresses and contaminations. Moreover, mollusk, particularly hemocytes, rapidly respond to environmental changes, such as pollution, salinity changes, and desiccation, which makes them an attractive model for this purpose. Thus, bivalve mollusks could be considered a good animal model to examine a system's response to different environmental conditions and stressors. miRNAs have been reported to adjust the adaptation and physiological functions of bivalves during endogenous and environmental stressors. In this review, we aimed to discuss the potential mechanisms underlying the response of bivalves to stressors and how miRNAs orchestrate this process; however, if necessary, other organisms' response is included to explain specific processes.

Effect of chrysophanic acid on immune response and immune genes transcriptomic profile in Catla catla against Aeromonas hydrophila

The effect of chrysophanic acid (CA) (2, 4, and 8 mg kg^-1) on the immunity and immune-related gene profile of Catla catla against Aeromonas hydrophila is reported. In both control and treated groups fed with 2 mg kg^-1 (2 CA), the phagocytosis, hemolytic, myeloperoxidase content, and superoxide anion production decreased significantly between 6th and 8th weeks, whereas when fed with 4 mg kg^-1 CA (4 CA) the H₂O₂ production and nitric oxide synthase increased significantly between 4th and 8th week. When fed with 2 CA and 4 CA diets, the total protein, bactericidal, and antibody titer increased significantly from the 4th week onwards. When fed with 2 CA, the IL-1β and IL-10 mRNA expression of head kidney leucocytes were significant between weeks 6 and 8. The expressions of toll-like receptors significantly increased when fed with a 4 CA diet from 4th week onwards. The 4 CA group significantly increased in TNF-α, TNF receptor-associated factor 6 (NOD), which influences protein expression, after the 4th week. The mRNA transcription of MHCI, lysozyme-chicken and goose type expressions significantly increased in 4 CA group within the 4th week. In summary, the dietary administration of 4 mg kg^-1 of CA (4 CA) provides better immunity and enhances the up-regulation of immune-related genes in Catla against A. hydrophila.

Combined effects of moderate hypoxia, pesticides and PCBs upon crucian carp fish, Carassius carassius, from a freshwater lake- in situ ecophysiological approach

Nowadays, depletion of oxygen or hypoxia has become a real concerning problem worldwide in freshwater, marine, and estuarine ecosystems and very often co-occurs with xenobiotics. Even though the acute and severe hypoxia is heavily studied in environment and laboratory studies, the in situ combined effects of these stressors on freshwater lake organisms are poorly understood. The current study sought to understand how the combined effects of moderate hypoxia, pesticides and PCBs affect the biochemistry, physiology and organ morphology of Carassius carassius, residing in the Lake Seferani, Dumrea region (Elbasan, Albania), a natural karst freshwater system declared as Nature Monument situated in central Albania. Crucian carp is used as a model organism, because of its residency and ecological relevance to the Lake, as well as for its amenability for the environmental toxicology studies. For this purpose, blood, liver and kidney samples of fish were processed for hematological, biochemical and histopathological analysis. We found a significant increase of blood glucose (GLU), cortisol levels, hematocrit (PCV) and hemoglobin (Hb) which clearly indicate the presence of stress in fish. Based on the histopathological evaluation and organ index results, liver and kidney organs displayed moderate-to-heavy histological-architecture changes. Our results provide a strong evidence that both, hypoxia and the presence of pesticides and PCB congeners found in Seferani Lake, put a heavy load on C. carassius energy metabolism and endocrine system, leading to an elevation of the biochemical and physiological parameters (hemoglobin level, hematocrit, glucose and cortisol), as well as the histopathological alterations. Additionally, in the presence of moderate hypoxia, the toxic effects of pesticides and PCBs on C. carassius are exacerbated. Further studies are needed to evaluate possible effects of pesticide and PCBs toxicity in human health, since crucian carp has an economic value for the population of the zone and it is used often as food sustenance. Elucidation of these kinds of responses can better improve our understanding of response of highly tolerant species, like Carassius carassius, to multiple stressors interactions, helping us to better predict and manage the consequences of the exposure of the freshwater biota to complex stressors in an environment that changes rapidly.

Impacts of salicylic acid in Mytilus galloprovincialis exposed to warming conditions

While many studies have been conducted on drug-inducing alterations in the aquatic environment, little is known about their interaction with climate change, such as rising temperatures. To increase knowledge on this topic, Mytilus galloprovincialis mussels were exposed to two different temperatures 17 ± 1 °C (control) and 21 ± 1 °C in the absence and presence of salicylic acid (SA) (4 mg/L) for 28 days. Salicylic acid in the water and tissues was measured and its impact reported through biomarker responses including: energy metabolism (electron transport system (ETS) activity, glycogen (GLY), protein (PROT) and lipids (LIP) contents), oxidative stress markers (activity of the enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx)), glutathione balance between the reduced and the oxidized forms (GSH/GSSG), and damage to membrane lipids (lipid peroxidation - LPO). The mussels responded differently if the stresses imposed were single or combined, with greater impacts when both stressors were acting together. Contaminated mussels exposed to high temperatures were unable to increase their metabolic capacity to restore their defence mechanisms, reducing the expenditure of LIP. In the presence of SA and increased temperature antioxidant defences respond differently, with higher SOD levels and inhibition of CAT. The present study highlights not only the negative impact of warming and SA, but especially how temperature increase will promote the impact of SA in M. galloprovincialis, which under predicted climate change scenarios may greatly impair population maintenance and ecosystem biodiversity.

Immunomodulation, antioxidant enhancement and immune genes up-regulation in rainbow trout (Oncorhynchus mykiss) fed on seaweeds included diets

This study investigated the stimulatory effects of dietary inclusion of Gracilariopsis persica (GP), Hypnea flagelliformis (HF) and Sargassum boveanum (SB) on immune indices, antioxidant capability and immune related genes expression of rainbow trout (Oncorhynchus mykiss). Seven iso-nitrogenous and iso-caloric diets with 0, 5 and 10% of each macroalgae were prepared and fed to rainbow trout juveniles for 83 days. Serum lysozyme (Lyz) and respiratory burst activity (NBT) along with activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) and expression of LyzII, TNFα and IL-1β genes in head kidney samples were determined by days 47 and 83. Our results revealed that dietary inclusion of seaweeds improved fish immune status. Long term feeding of fish on seaweed contained diets (except for GP10) improved serum Lyz activity in comparison to control group. Similarly, extended feeding on GP5 and HF10 and HF10 included diets improved SOD and POD levels, respectively. Genes expression studies revealed that seaweeds contained diets noticeably enhanced expression of LyzII, TNFα and IL-1β in comparison to control fish. However, results revealed that such stimulatory effects were more evident at lower dietary inclusion level and shorter feeding time. In conclusion, the results depicted that dietary inclusion of the seaweeds effectively improved serum immune indices and head kidney antioxidant status and immune related genes expression in a time and dose dependent manner.

Acute effects of neonicotinoid insecticides on Mytilus galloprovincialis: A case study with the active compound thiacloprid and the commercial formulation calypso 480 SC

Pesticides can enter aquatic environments potentially affecting non-target organisms. Unfortunately, the effects of such substances are still poorly understood. This study investigated the effects of the active neonicotinoid substance thiacloprid (TH) and the commercial product Calypso 480 SC (CA) (active compound 40.4% TH) on Mytilus galloprovincialis after short-term exposure to sublethal concentrations. Mussels were tested for seven days to 0, 1, 5 and 10 mg L^-1 TH and 0, 10, 50 and 100 mg L^-1 CA. For this purpose, several parameters, such as cell viability of haemocytes and digestive cells, biochemical haemolymph features, superoxide dismutase (SOD) and catalase (CAT) enzymatic activity of gills and digestive gland, as well as histology of such tissues were analysed. The sublethal concentrations of both substances lead to abatement or completely stopping the byssal fibres creation. Biochemical analysis of haemolymph showed significant changes (P < 0.01) in electrolytes ions (Cl^-, K⁺, Na⁺, Ca²⁺, S-phosphor), lactate dehydrogenase (LDH) enzyme activity and glucose concentration following exposure to both substances. The TH-exposed mussels showed significant imbalance (P < 0.05) in CAT activity in digestive gland and gills. CA caused significant decrease (P < 0.05) in SOD activity in gills and in CAT activity in both tissues. Results of histological analyses showed severe damage in both digestive gland and gills in a time- and concentration-dependent manner. This study provides useful information about the acute toxicity of a neonicotinoid compound and a commercial insecticide on mussels. Nevertheless, considering that neonicotinoids are still widely used and that mussels are very important species for marine environment and human consumption, further researches are needed to better comprehend the potential risk posed by such compounds to aquatic non-target species.

A new digestion approach for the extraction of microplastics from gastrointestinal tracts (GITs) of the common dolphinfish (Coryphaena hippurus) from the western Mediterranean Sea

Plastic ingestion is one of the main impacts of marine litter on organisms. The occurrence of microplastics (MPs < 5 mm) in the stomachs of Mediterranean species was already reported in several studies. In this context, the present study aims to develop a new approach of digestion for the identification of MPs in the gastrointestinal tracts (GITs) of marine organisms. The new approach combines two digestion protocols, including potassium hydroxide (KOH) and nitric acid (HNO₃), to remove most organic and inorganic materials. This digestion allows recording small MPs that are difficult to find via routinely stomach content analysis and also to minimize the overestimation of the phenomenon trough the control of airborne contamination. The new approach was tested on a voracious pelagic opportunistic predator, the common dolphinfish, a fishery resource exploited in several Mediterranean areas. The results showed that a large amount of ingested meso- and microplastics, such as fragments or sheets, was recorded in GITs (F = 65.5 %). The FTIR analysis on litter samples allowed to identify polyethylene, polypropylene and polystyrene as dominant constituent polymers of microplastics. These results confirmed that our novel combined digestion protocol represents a reliable approach to detect MPs in opportunistic pelagic predators.

Embryotoxicity of atrazine and its degradation products to early life stages of zebrafish (Danio rerio)

Triazine herbicide atrazine is considered to be moderately toxic to various aquatic animals. The aim of our study was to evaluate the acute embryotoxicity of atrazine and its two degradation products, desisopropylatrazine and desethylatrazine, and their mixture to the early life stages of zebrafish (Danio rerio) by means of a modified method of the Fish Embryo Acute Toxicity (FET) Test - OECD guideline 236. Toxic effects were studied by the evaluation of lethal endpoints and development of disorders. Furthermore, sublethal endpoints such as hatching rate, formation of somites, development of eyes, spontaneous movement, heartbeat, blood circulation, pigmentation and occurrence of edema at 24, 48, 72 and 96 h post fertilization were assessed. Newly fertilized eggs were exposed to various concentrations of atrazine, desisopropylatrazine and desethylatrazine, and their combination 0.3, 30, 100, 300, 1000, 3,000 and 10,000 μg/l, which represent environmentally relevant levels of these pollutants in surface waters and multiples of these concentrations to find out if the toxic effect depends on dose. Single substances and their combination were not associated with a negative effect on mortality. Rare malformations were observed during these embryonal toxicity tests. Only pericardial edema was recorded during the monitored observation. A significant increase in the occurrence of pericardial edema between the control 0% and the experimental group 17.6 %) was found only in the group exposed to the highest concentration of a triazine herbicide combination (10,000 μg/l) at 72 and 96 h post fertilization. Obtained results indicate that especially higher not environmentally relevant concentrations of atrazine, its metabolites or their combination present a potencial risk of embryotoxicity for zebrafish.

Humoral and skin mucosal immune parameters, intestinal immune related genes expression and antioxidant defense in rainbow trout (Oncorhynchus mykiss) fed olive (Olea europea L.) waste

A six-week feeding trial was carried out to evaluate the effects of inclusion of dietary olive waste cake (OWC, 0, 0.5, 2.5 and 5 g kg^-1 diet) on performance, antioxidant condition and immune responses of rainbow trout (Oncorhynchus mykiss) (2.5 ± 0.1 g). Supplementing diet with 2.5 and 5 g OWC kg^-1 diet significantly enhanced serum and mucosal lysozyme activity in fish. Regarding mucosal immunity, fish fed 2.5 and 5 g OWC kg^-1 diets had higher skin mucus total Ig concentrations than other groups. In relation to antioxidant status, those in 2.5 g OWC kg^-1 and the control groups exhibited the highest and the least liver superoxide dismutase and glutathione peroxidase activities, respectively. Furthermore, the activity of liver glutathione S transferase in fish fed 2.5 and 5 g OWC kg^-1 diets was higher than the other treatments. In respect to gut cytokines gene expression, our findings demonstrated dietary OWC did not influence interlukines-1β and 10 genes expression, but relative expression of IL8 gene gradually up-regulated with increasing dietary OWC level. Moreover, fish fed 0.5 g OWC kg^-1 and the control diets had the highest and the lowest gut tumor necrosis factor-α gene expression values, respectively. The relative expression of transforming growth factor-β significantly down-regulated in gut of fish fed 2.5 and 5 g OWC kg^-1 diets compared to other groups. Supplementing diet with OWC pronouncedly improved growth and feed conversion ratio in fish compared to the control. Overall, the findings of this study suggested that inclusion of 2.5 g OWC kg^-1 diet can improve growth rate, oxidative stress status, humoral and skin mucosal immune responses in O. mykiss fingerlings and it can be considered as a functional feed additive for this species.

Combined effects of salinity changes and salicylic acid exposure in Mytilus galloprovincialis

Pharmaceuticals and Personal care products (PPCPs) are frequently released into several marine matrices, representing significant environmental and ecotoxicological risks. Among the widest spread PPCPs in aquatic systems is Salicylic acid (SA), with known negative effects on marine and freshwater species. Nevertheless, the toxicity resulting from these emerging pollutants, including SA, together with climate change has still received little attention up to date. Among climate change related factors salinity is one that most affects aquatic organisms. To better understand the combined impacts of SA and salinity, the present study evaluated the biochemical alterations induced in Mytilus galloprovincialis mussels exposed to SA and different salinity levels, acting individually and in combination. The effects observed clearly highlighted that cellular damages were mainly observed at higher salinity (35), with no additive or synergistic effects derived from the combined presence of SA. Higher antioxidant capacity of mussels in the presence of SA may prevent increased LPO levels in comparison to uncontaminated mussels. Nevertheless, in the presence of SA mussels revealed loss of redox balance, regardless of the salinity level. Furthermore, mussels exposed to SA at control salinity showed increased metabolic capacity which decreased when exposed to salinities 25 and 35. These findings may indicate the protective capacity of mussels towards higher stressful conditions, with lower energy reserves expenditure when in the presence of SA and salinities out of their optimal range. Although limited cellular damages were observed, changes on mussel's redox balance, antioxidant mechanisms and metabolism derived from the combined exposure to SA and salinity changes may compromise mussel's growth and reproduction. Overall, the present study highlights the need to investigate the impacts induced by pollutants under present and future climate change scenarios, towards a more realistic environmental risk assessment.

Physiological and biochemical responses of Mediterranean green crab, Carcinus aestuarii, to different environmental stressors: Evaluation of hemocyte toxicity and its possible effects on immune response

Effects of natural stressors such as copper (Cu²⁺), temperature, hypoxia, chloroform and adrenaline on physiological and biochemical responses were investigated in the Mediterranean green crab Carcinus aestuarii from tidal shallow waters of Narta Lagoon, Albania. For this purpose, hemolymph glucose levels, total and differential hemocyte count, in normal and eye-stalked individuals, exposed to above mentioned stressors like, were assessed. In addition, lysosomal membrane stability was evaluated as biomarker of hemocyte toxicity, with possible implications on crab immune response. Hemolymph glucose levels were significantly increased in all treatment groups with 1.25-to 3.5-fold above baseline levels of 37.8 ± 2.7 mgdL^-1. Response times were being manifested within 30-120 min following exposure and recovery happened within 2 h of restoration of pretreatment conditions. Total hemocyte count (THC) and differential hemocyte count (DCH) showed a significant decrease for all stressors, except for copper, were an increase of semi-granular hemocyte fraction were recorded. Meanwhile, significant reduction of neutral red retention time (NRRT), in both eyestalk-ablated and exposed animals, were recorded, indicated the loss of hemocyte lysosomal membrane integrity. The responsiveness of hemolymph blood levels to all stressors, the decrease in total hemocyte count, as well as the loss of lysosomal membrane integrity demonstrated that exposure to environmentally realistic stressors placed a heavy metabolic load on C. aestuarii, modulating their immune competence and overall physiological wellness. Overall, results suggest that monitoring cellular and biochemical parameters like hemolymph glucose titres, TCH, DHC and NRRT, may be useful and sensitive means of evaluating the crustacean's ability to cope with the wide variety of environmental stressors through modulation of the immune parameters.

Effects of dietary Origanum vulgare on gilthead seabream (Sparus aurata L.) immune and antioxidant status

Origanum sp. is a very common genus of aromatic plants worldwide distributed around the Mediterranean area and O. vulgare (oregano) is the most important species of this genus throughout the world. Due the known medicinal properties of oregano, the effect of diets enriched with 0% (control), 0.5% and 1% oregano leaves powder was studied on the growth, immune and antioxidant status of gilthead seabream (Sparus aurata L.). Fish fed with oregano 0.5% and 1% enriched diets improved both humoral (IgM and bactericidal activity in skin mucus and protease activity in serum) and cellular (head kidney leucocytes phagocytic ability) immunity at 15 and 30 days. Furthermore, the addition of oregano did not provoke any significant effect neither in the growth promotion nor in the liver antioxidant enzymes activity studied in the serum and skin mucus. The possibility of using O. vulgare as a functional additive to fish diet is discussed.

Evaluation of softwood and hardwood sawmill wastes impact on the common carp "Cyprinus carpio" and its aquatic environment: An oxidative stress study

The aquatic pollution due to sawmill wood wastes constitutes a major threat to hydro-chemical and fauna characteristics of the aquatic ecosystems. When this kind of organics wastes enter aquatic environment it can be taken up by aquatic organisms through respiration and/or through their diet. This could concurrently result in oxidative stress and later having adverse effect on physiological and biochemical function. The importance of fish in the society cannot be over emphasized, hence there is the need to know the influence of sawmill wood wastes on the water quality and fish. Therefore, this work aims to study the impact of five species of wood wastes on a type of fish named common carp (Cyprinus carpio) known as the most widely cultured fish species in the world and on its aquatic environment. The monitoring of water parameters showed deterioration in water quality. The activities of superoxide dismutase (SOD), Catalase (CAT), glutathione peroxidase (GPx) and lipid peroxidation (MDA) were investigated to evaluate the degree of oxidative stress. According to t-student, there was a significant difference compared to control (P < 0.05) in the level of SOD, CAT, GPx and MDA activities in fish exposed to 5 g·l^-1 of each sawdust except for GPx, a non-significant difference (p > 0.05) was noted in the case of Beech and Dibetou. When the dispersed amount was about 0.375 g·l^-1 we noted a significant difference in the level of SOD and GPx, except for GPx a non-significant difference was detected in the case of Cedar. The level of CAT was significantly difference just in the case of Cedar and Dibetou and that of MDA was significantly difference just in the case of Beech and Mahogany. We conclude therefore that sawmill wood waste not only impact the water quality adversely but also alters the levels of different enzymes activities in Cyprinus Carpio fish by the inhibition of SOD, CAT and GPx activities and by the production of MDA, which reflects response to oxidative stress. This study provides a rational use of these enzymes as suitable biomarkers with different degrees of specificity and as important tool for environmental monitoring.

The effect of foodborne sertraline on rainbow trout (Oncorhynchus mykiss)

The worldwide consumption of antidepressants is raising as well as their concentrations in the aquatic environment. This increases the risk of food chain contamination and bioaccumulation in aquatic biota. The aim of this study was to describe a potential risk of sertraline as a pollutant from water environment, wherein rainbow trout (Oncorhynchus mykiss) has been chosen as the test organism, because predatory fish are on the top of the food chain in the aquatic environment. The effects of foodborne sertraline were tested on rainbow trout during a 28-day toxicity test according to OECD 215 method. Sertraline was incorporated in commercial feed at a dose of 4.4 µg/kg (environmental concentration), 42 µg/kg and 400 µg/kg. The results confirmed that sertraline has a significant effect on fish behaviour, resulting in suppression of the escape reflex and increased resistance to stress. Moreover, increased Fultońs condition factor was found in fish fed with the highest concentration of sertraline. Haematological analysis revealed a statistically significant increase in the number of neutrophilic bands and neutrophil/lymphocyte ratio, and decreased number of lymphocytes. The results of biochemical examination showed a statistically significant decrease in ammonia and lactate concentrations and histological examination revealed changes in gills and caudal kidney. Although sertraline reduces stress in fish, the decline in nonspecific immunity is a risk to fish population stability.

Common carp, Cyprinus carpio, prefer branchial ionoregulation at high feeding rates and kidney ionoregulation when food supply is limited: additional effects of cortisol and exercise

This study aims to examine ionoregulatory parameters during exercise and cortisol elevation in common carp fed different food rations. Fish subjected to two different feeding regimes (0.5 or 3.0% body mass (BM) daily) received no implant or an intraperitoneal cortisol implant (250 mg/kg BM) or sham, and were monitored over a 168-h post-implant (PI) period under resting, low aerobic swimming or exhaustive swimming conditions. Plasma osmolality was maintained at relatively stable levels without much influence of feeding, swimming or cortisol, especially in low feeding groups. Nevertheless, a transient hyponatremia was observed in all low feeding fish implanted with cortisol. The hyponatremia was more pronounced in fish swum to exhaustion but even in this group, Na⁺ levels returned to control levels as cortisol levels recovered (168 h-PI). Cortisol-implanted fish also had lower plasma Cl^- levels, and this loss of plasma Cl^- was more prominent in fish fed a high ration during exhaustive swimming (recovered at 168 h-PI). Cortisol stimulated branchial NKA and H⁺ ATPase activities, especially in high ration fish. In contrast, low ration fish upregulated kidney NKA and H⁺ ATPase activities when experiencing elevated levels of cortisol. In conclusion, low feeding fish experience an ionoregulatory disturbance in response to cortisol implantation especially when swum to exhaustion in contrast to high feeding fish.

Assessing the effects of neonicotinoid insecticide on the bivalve mollusc Mytilus galloprovincialis

In the present work, the marine invertebrate Mytilus galloprovincialis was used as model organism to evaluate the toxic effects of the neonicotinoid Calypso 480 SC (CAL) following 20 days of exposure to sub-lethal concentrations of 7.77 mg L^-1 (0.1% 96 h-LC50) and 77.70 mg L^-1 (1% 96 h-LC50), and a recovery period of 10 days in uncontaminated seawater. Results revealed that exposure to both concentrations of CAL increased significantly mortality rate in the cells of haemolymph and digestive gland, while digestive gland cells were no longer able to regulate cell volume. Exposure significantly reduced haemolymph parameters (Cl^-, Na⁺), affected the enzymatic activities of superoxide dismutase of digestive gland and catalase of gill, and caused also histopathological alterations in digestive gland and gills. Main histological damages detected in mussels were lipofuscin accumulation, focal points of necrosis, mucous overproduction and infiltrative inflammations. Interestingly, alterations persisted after the recovery period in CAL-free water, especially for haemocyte parameters (K⁺, Na⁺, Ca²⁺, lactate dehydrogenase, glucose). A slight recovery of histological conditions was detected. These findings suggested that sub-chronic exposure to the neonicotinoid insecticide caused significant alterations in both cell and tissue parameters of M. galloprovincialis. Considering the ecologically and commercially important role of mussels in coastal waters, a potential risk posed by neonicotinoids to this essential aquatic resource can be highlighted.

Toxic impacts induced by Sodium lauryl sulfate in Mytilus galloprovincialis

Pharmaceuticals and personal care products (PPCPs) are continuously dispersed into the environment, as a result of human and veterinary use, reaching aquatic coastal systems and inhabiting organisms. However, information regarding to toxic effects of these compounds towards marine invertebrates is still scarce, especially in what regards to metabolic capacity and oxidative status alterations induced in bivalves after chronic exposure. In the present study, the toxic impacts of Sodium lauryl sulfate (SLS), an anionic surfactant widely used as an emulsifying cleaning agent in household and cosmetics, were evaluated in the mussel Mytilus galloprovincialis, after exposure for 28 days to different concentrations (0.0; 0.5; 1.0; 2.0 and 4.0 mg/L). For this, effects on mussels respitation rate, metabolic capacity and oxidative status were evaluated. The obtained results indicate a significant decrease on mussel's respiration rate after exposure to different SLS concentrations, an alteration that was accompanied by a decrease of bioconcentration factor along the increasing exposure gradient, especially at the highest exposure concentration. Nonetheless, the amount of SLS accumulated in organisms originated alterations in mussel's metabolic performance, with higher metabolic capacity up to 2.0 mg/L followed by a decrease at the highest tested concentration (4.0 mg/L). Mussels exposed to SLS revealed limited antioxidant defense mecanhisms but cellular damage was only observed at the highest exposure concentration (4.0 mg/L). In fact, up to 2.0 mg/L of SLS limited toxic impacts were observed, namely in terms of oxidative stress and redox balance. However, since mussel's respiration rate was greatly affected by the presence of SLS, the present study may highlight the potential threat of SLS towards marine bivalves, limiting their filtration capacity and, thus, affecting their global physiological development (including growth and reproduction) and ultimely their biochemical performance (afecting their defense capacity towards stressful conditons).

Extract of common mallow (Malvae sylvestris) enhances growth, immunity, and resistance of rainbow trout (Oncorhynchus mykiss) fingerlings against Yersinia ruckeri infection

The dietary effects of a native medicinal plant from Iran, common mallow (Malvae sylvestris), was evaluated on growth performance, innate immune parameters, mucosal immune parameters, and resistance of rainbow trout (Oncorhynchus mykiss) against Yersinia ruckeri. Therefore, 360 fish (initial weight 10.42 ± 0.09 g) were randomly distributed into 12 fiberglass tanks. Experimental diets supplemented with 0 (as control- C), 1% (M1), 3% (M2) and 5% (M3) levels of M. sylvestris flowers extract were fed to the fish based on 3% of body weight for 8 weeks. At the terminal sampling, growth performance, liver and digestive enzymes activities, blood and mucosal immune responses were determined. Results showed that M2 and M3 had greater final weight, weight gain, SGR, survival rate and lower FCR; higher levels of total protein, albumin, globulin, and lower cortisol levels in comparison to control; 5% extract also lowered cholesterol and glucose levels as well as Lactate Dehydrogenase (LDH) activity. We reported higher values of hematocrit, hemoglobin, Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Volume (MCV), White Blood Cell (WBC), Red Blood Cell (RBC) and lymphocytes for treated groups. Innate immune responses (Alternative complement activity (ACH50) in M2 and M3 group, total Immunoglobulin (Ig) and lysozyme in M3), mucosal immune parameters (ACH50, total Ig for M2 and M3 group and lysozyme in all treated groups) were enhanced. Activities of digestive enzymes (protease in all treated groups, amylase for 3 and 5%, while lipase only for 5%) and lower activity of liver ALT enzyme in individuals treated with highest dose was observed. Overall results indicated that the extract can positively affect growth performance and immune responses of rainbow trout.

Rutin as Neuroprotective Agent: From Bench to Bedside

Flavonoids are major dietary constituents of plant-based food found ubiquitously in plant kingdom where they are usually present in substantial amounts. Rutin is a flavonol-type polyphenol which consists of the flavonol quercetin and the disaccharide rutinose. Rutin has been reported to exert diverse biological effects such as antitumor and antimicrobial mainly associated to its antioxidant and anti-inflammatory activities. Mental, neurological, and behavioural disorders are an important and growing cause of morbidity. Most of these disorders combine a high prevalence, early onset, progressive clinical course, and impairment of critical brain functions making them a major contributor to the global disease burden. In the present work, the biological in vitro and in vivo effects and the potential therapeutic applications of rutin in neurodegenerative processes are reviewed, as well as their bioavailability and pharmacokinetics, which are essential for a better understanding of its biological effectiveness. Moreover, the present review also provides an overview of the molecular mechanisms through which rutin is proposed to exert its neuroprotective effects.

Detection of artificial cellulose microfibers in Boops boops from the northern coasts of Sicily (Central Mediterranean)

Pollution deriving from textile wastes, including industrial and household waste, is recently of great interest due to their environmental impacts. Anthropogenic and synthetic fibers are responsible for negative effects on the quality of water and soil, and, also, their presence damages plant and animal health. In this work, the authors revealed the occurrence of man-made cellulose fibers in specimens of Boops boops from the Northern Sicilian coasts. Bogue was chosen as target species as it has been used as an indicator within the European Marine Strategy Framework Directive (MSFD 2008/56/EC) in order to value the "microplastics status" in the stomach contents. Of the 30 specimens examined, 63.3% of these had ingested fibers items. The number of fibers ranged from 1 to 10 per specimens with an average of 2.7 items/specimen. Fibers length ranged from 0.5 to 30 mm, most of them were black (95%), and a small percentage was red (5%). The ingestion of man-made cellulose fibers, observed for the first time, in Boops boops in the Mediterranean Sea wake-up call and it should attract the attention of the EU for new guidelines where this new type of contaminant is classified harmful as well as plastics.

Effects of Assam tea extract on growth, skin mucus, serum immunity and disease resistance of Nile tilapia (Oreochromis niloticus) against Streptococcus agalactiae

The present study aimed to assess the possible effects of Assam tea (Camellia sinensis) extract (ATE) on growth performances, immune responses, and disease resistance of Nile tilapia, Oreochromis niloticus against Streptococcus agalactiae. Five levels of ATE were supplemented into the based diet at 0, 1, 2, 4, and 8 g kg^-1 feed of Nile tilapia fingerlings (10.9 ± 0.04 g initial weight) in triplicate. After four and eight weeks of feeding, fish were sampled to determine the effects of the tea supplements upon their growth performance, as well as serum and mucosal immune responses. A disease challenge using S. agalactiae was conducted at the end of the feeding trial. Fish fed ATE revealed significantly improved serum lysozyme, peroxidase, alternative complement (ACH50), phagocytosis, and respiratory burst activities compared to the basal control fed fish (P < 0.05). The mucus lysozyme and peroxidase activities were ameliorated through ATE supplementation in the tilapia diets. Supplementation of ATE significantly (P < 0.05) enhanced final body weight, weight gain, and specific growth rate; while a decreased feed conversion ratio was revealed at 2 g kg^-1 inclusion level, after four and eight weeks. Challenge test showed that the relative percent survival (RSP) of fish in each treatment was 33.33%, 60.00%, 83.33%, 76.68%, and 66.68% in groups fed 0, 1, 2, 4, and 8 g kg^-1, respectively. In summary, diets supplemented with ATE especially at 2 g kg^-1 increased the humoral and mucosal immunity, enhanced growth performance, and offered higher resistance against S. agalactiae infection in Nile tilapia.

Amphibian embryos as an alternative model to study the pharmaceutical toxicity of cyclophosphamide and ibuprofen

Pharmaceuticals are becoming potentially ubiquitous pollutants because of their extensive use by man. One of the most frequent groups of pharmaceuticals that have been identified as particularly concerning is that of nonsteroidal anti-inflammatory and chemotherapeutic drugs. In Albania, studies to determine the risk of pharmaceuticals in conjunction with their occurrence in water bodies and their adverse effects on living organisms, including humans, are scarce. The purpose of this study was to elucidate the possible toxic effects of ibuprofen (IBU) and cyclophosphamide (CP) on cellular physiology of frog tadpoles. For this purpose, individuals of Pelophylax shqipericus belonging to stage 21 Gosner were exposed to sub-lethal concentration (5 μg/L) of IBU and CP for 48 hours, and erythrocyte abnormalities and micronucleated cell frequency were evaluated as endpoints. Blood smears from tadpoles exposed to CP for 48 hours showed a pronounced decrease in the number of red blood cells and an increase in the percentage of micronucleated erythrocytes through chromatin fragmentation, while abnormalities like cellular and nuclear vacuolization, collapse and rupture of the cell membrane were caused by IBU toxicity. Understanding the biological effects of these drugs on frog tadpoles can help in using these animals as reliable bio-indicator organisms in monitoring aquatic environments health.

Oxidative stress induction by the invasive sponge Paraleucilla magna growing on Peyssonnelia squamaria algae

The introduction of invasive species can lead to significant adverse effects on the colonized areas. The aim of the present research was to determine if the invasive behavior of Paraleucilla magna could induce the activation of the antioxidant defences in the native red algae, Peyssonnelia squamaria. Individuals of isolated P. squamaria and individuals epiphytized by P. magna, both growing on rocky bottoms, were collected. The activity of the antioxidant enzymes - catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase - and the levels of the malondialdehyde were significantly higher in the algae of the epiphytic group compared to the control group, while the detoxifying enzyme glutathione S-transferase did not show significant differences. The levels of reduced glutathione and total polyphenols were higher in the algae affected by the sponge. In conclusion, the arrival of the species P. magna induces an adaptative antioxidant response in P. squamaria determined by the use of biomarkers.

Biochemical and physiological responses induced in Mytilus galloprovincialis after a chronic exposure to salicylic acid

A vast variety of substances currently reaches the aquatic environment, including newly developed chemicals and products. Lack of appropriate analytical methods for trace determinations in aquatic ecosystem compartments and lack of information regarding their toxicity explains existing regulation gaps. However, suspicion of their toxicity assigned them as Contaminants of Emerging Concern (CECs). Among CECs are Pharmaceuticals including Salicylic Acid (SA), which is the active metabolite of acetylsalicylic acid (ASA; aspirin). The aim of the present study was to evaluate the potential effects of SA on the mussel Mytilus galloprovincialis. For this, organisms were exposed for 28 days to different concentrations of SA (0.005; 0.05; 0.5 and 5 mg/L), resembling low to highly polluted sites, after which different physiological and biochemical parameters were evaluated to assess organism's respiration rate, neurotoxic, metabolic and oxidative stress status. Our results clearly showed that SA strongly reduced the respiration capacity of mussels. Also, SA inhibited the activity of superoxide dismutase (SOD) and catalase (CAT) enzymes, but increased the activity of glutathione peroxidase (GPx) and glutathione-S-transferases (GSTs), which prevented the occurrence of lipid peroxidation (LPO). Nevertheless, oxidative stress was confirmed by the strong decrease of the ratio between reduce glutathione (GSH) and oxidized (GSSG) glutathione in contaminated mussels. Moreover, neurotoxicity was observed in mussels exposed to SA. Overall, this study demonstrates the metabolic, neurotoxic and oxidative stress impacts of SA in M. galloprovincialis, which may result in negative consequences at the population level.

Mephedrone Impact on Matrix Metalloproteinases Activity - Do they Influence the Memory Processes?

BACKGROUND

The use of drugs of addiction, as mephedrone, is associated with functional neuronal disorders due to remodeling of the nervous tissue. Key enzymes in remodeling are extracellular matrix (ECM) proteases like matrix metalloproteases (MMPs). Recently, MMPs have been of great interest as some studies point to a fact that the alterations in structural remodeling of synaptic connections modify learning-dependent changes, which remain active even after a prolonged period of abstinence. This entails a continuous development of dependence.

OBJECTIVES

The aim of the study was to determine the influence of subchronic exposure to three different doses of mephedrone on the activity of MMP-2 and 9 in hippocampus and prefrontal cortex and how this was correlated with memory processes in mice.

METHODS

The homogenates of hippocampus and cortex were assayed for MMP-2 and MMP-9 activity by gelatin zymography. Memory consolidation processes were evaluated in the passive avoidance (PA) test.

RESULTS

The study confirmed the dose-dependent increase in activity of MMP-2 and -9 exerted by subchronic administration of mephedrone. Moreover, the highest dose of mephedrone attenuated consolidation of memory and learning processes.

CONCLUSIONS

We could hypothesize that inhibition of MMPs can be considered as a therapeutic option for the treatment of addictive behaviors associated with cognitive processes. Moreover, further studies are required to find out if elevated activities of MMPs contribute to brain damage or recovery from brain damage caused directly by mephedrone.

Correction to: Triggering of eryptosis, the suicidal erythrocyte death, by phenoxodiol

The original version of this article contains several mistakes due to the missed corrections.