Adverse effects of environmentally relevant concentration of microplastics on gill epithelium permeability in the euryhaline Mediterranean killifish Aphanius fasciatus.

Estuaries and lagoons are characterized by fluctuating salinity and significant amounts of microplastics (MPs) and are increasingly subjected to various anthropogenic pressures. We investigated whether the accumulation of MPs in the gills of fish inhabiting these fragile ecosystems alters osmoregulation and, consequently, their ability to tolerate fluctuating salinity. The effects of a 15-day exposure to an environmentally relevant concentration (20 μg/L) of spherical polystyrene microplastics (PS-MPs) with a diameter of 5 μm were assessed in the Mediterranean killifish Aphanius fasciatus, focusing on tissue and gene expression changes related to factors of paracellular and transcellular permeability of the gill epithelium during the transition from seawater to freshwater.

Effect of thyroid disruption on ovarian development following maternal exposure to Bisphenol S.

Thyroid hormones play a crucial role in numerous physiological processes, including reproduction. Bisphenol S (BPS) is a structural analog of Bisphenol A known for its toxic effects. Interference of this substitute with normal thyroid function has been described.

Combined toxic effects of cadmium and environmental microplastics in Aphanius fasciatus (Pisces, Cyprinodontidae).

Microplastics (MPs), plastic particles smaller than 5 mm in diameter, have received extensive attention as new environmental pollutants with still unexplored potential ecological risks. The main objective of the present study is to see if the concomitant exposure to MPs and Cd is more toxic than that to MPs or Cd separately in Aphanius fasciatus. Immature female were exposed to Cd and/or MPs for 21 days, and the subsequent effects were monitored by a combination of biochemical, histological and molecular toxicity markers.

Interference with zinc homeostasis and oxidative stress induction as probable mechanisms for cadmium-induced embryo-toxicity in zebrafish.

The present study was conducted to provide new insights into the mechanisms that may be responsible for cadmium (Cd)-induced toxicity in zebrafish larvae as well as the role of the trace element zinc (Zn) in reversing Cd harmful effects. For this purpose, zebrafish eggs were exposed to Cd or/and Zn for 96 h. The effects on morphological aspect; mortality rate; Cd, Zn, and metallothionein (MT) levels; oxidative stress biomarkers; as well as molecular expression of some genes involved in Zn metabolism (Zn-MT, ZIP10, and ZnT1) and in antioxidant defense system (Cu/Zn-SOD, CAT and GPx) were examined.

Exposure to microplastics leads to a defective ovarian function and change in cytoskeleton protein expression in rat.

Microplastics (MPs) are ubiquitous environmental contaminants; through their physicochemical properties, they can have potentially negative effects on the environment as well as on animal and human health. Studies addressing the toxicity of MPs on mammalian female reproduction are almost absent. Thus, the main objective of the present study was to assess the impact of oral exposure, during four estrous cycles, of 5 µm polystyrene-type microplastics (PS-MPs) on ovarian function in rats.

Aphanius fasciatus: a molecular model of scoliosis?

Study Design: Observational study of Killifish with spinal deformities OBJECTIVE: To evaluate the morphology and molecular biology of Aphanius fasciatus with severe spine deformities. Idiopathic Scoliosis affects 3% of the population and is an abnormal three-dimensional curvature of the spine with unknown cause. The lack of a model system with naturally occurring spinal curvatures has hindered research on the etiology of IS.

Effect of melatonin and folic acid supplementation on the growth performance, antioxidant status, and liver histology of the farmed gilthead sea bream (Sparus aurata L.) under standard rearing conditions.

The present study aimed to investigate the effect of dietary of melatonin (MLT) and folic acid (FA) administrations on growth performance, antioxidant status, and liver histological structure of juvenile gilthead sea bream, Sparus aurata L. under standard rearing conditions. Four diets were considered: a basal diet considered a control and three diets supplemented with 40 mg/kg of melatonin (MLT), 2 mg/kg of folic acid (FA), and with the mixture of melatonin and folic acid (MLT + FA).

First evidence on protective effect of exogenous melatonin supplementation against disruption of the estrogenic pathway in bone metabolism of killifish (Aphanius fasciatus).

This study was carried out to investigate the effects of exposure to estrogen antagonist nafoxidine hydrochloride (NH) and/or melatonin (Mlt) on certain bone metabolism parameters in killifish Aphanius fasciatus, a species suggested to be a suitable model for studying spinal deformities such as scoliosis. Immature females of A. fasciatus receiving 10 μg/L NH and/or 100 μg/L of Mlt were used and were sacrificed 30 days after the treatment.

Heavy metal accumulation and histomorphological alterations in Aphanius fasciatus (Pisces, Cyprinodontidae) from the Gulf of Gabes (Tunisia).

The present study illustrates an analysis of histological changes; cadmium (Cd), copper (Cu) and zinc (Zn) accumulation; and metallothionein (MT) levels in normal and deformed Mediterranean killifish, Aphanius fasciatus (Pisces, Cyprinodontidae), collected from unpolluted (S1) and polluted areas (S2) in the Gulf of Gabes in Tunisia. Metal determination in water and sediment showed that the concentrations were significantly higher (p < 0.0001) in S2 compared to S1.

Comparative study of longevity, growth, and biomarkers of metal detoxication and oxidative stress between normal and deformed Aphanius fasciatus (Pisces, Cyprinodontidae).

This study compared fish longevity, growth, and oxidative stress between normal and deformed Aphanius fasciatus collected from the Gulf of Gabes. For this purpose, fish were collected from control (S1) and polluted (S2) sites in Tunisian coast and percentages of spinal deformities were determined. Oxidative stress biomarkers were also compared between normal and deformed fish, including levels of protein sulfhydryl (SH), malondialdehyde (MDA), and metallothioneins (MT), as well as activities of superoxide dismutase (SOD) and alkaline phosphatase (AP).

Effects of cadmium and high temperature on some parameters of calcium metabolism in the killifish (Aphanius fasciatus).

This study aims to investigate the influence of high temperature on cadmium (Cd) toxicity in Aphanius fasciatus (Pisces: Cyprinodontidae). For this reason, Cd, mineral, and organic content in the vertebral column as well as the histological structure of gills and bone were compared in fishes exposed for 30 days to Cd (2 mg/L CdCl2) and/or high temperature (26 °C). Cd exposure caused a negative correlation between Cd and Ca concentrations (r = 0.

Possible chemical causes of skeletal deformities in natural populations of Aphanius fasciatus collected from the Tunisian coast.

This study attempt to quantify and identify skeletal deformities in natural populations of Aphanius fasciatus collected from the Tunisian coast and tends to found a possible relationship between these anomalies and several types of pollutants presents in the environment. Fish were collected from one reference area (S1: coast of Luza) and three polluted areas (S2: industrialized coast of Sfax, S3: coast of Khniss and S4: Hamdoun'Oued). Various patterns of skeletal deformities were diagnosed using double staining technics, and the levels of heavy metals (Cd, Cu and Zn), various polycyclic aromatic hydrocarbons (PAHs) and estrogenic compounds were determined in water and sediment from different sites.

Structural and molecular analysis of pollution-linked deformities in a natural Aphanius fasciatus (Valenciennes, 1821) population from the Tunisian coast.

The Eastern coast of Tunisia hosts a mosaic of populations of the Mediterranean killifish A. fasciatus, an excellent monitoring species for the analysis of environmental impact in coastal Mediterranean areas. Among these populations, fish from the Sfax area, in the Gulf of Gabès, are known for presenting a high prevalence of different physiological alterations, including spinal deformation.

Influence of cadmium exposure on growth and fecundity of freshwater mosquitofish Gambusia affinis: in situ and in vivo studies.

This study aims to investigate the effect of cadmium (Cd) exposure on growth and fecundity of mosquitofish Gambusia affinis. For this purpose, two natural populations of pregnant females of G. affinis captured from two sites were differently contaminated with Cd (S1 present Cd levels 5-fold higher than S2) and a sublethal exposure to 0.

Evaluation of environmental impact on natural populations of the Mediterranean killifish Aphanius fasciatus by quantitative RNA biomarkers.

The Mediterranean killifish, Aphanius fasciatus (Valenciennes, 1821) represents an excellent sentinel species for analysis of environmental impact in coastal areas. Quantitative changes on liver mRNA levels of five stress-related genes--metallothionein (metal exposure), vitellogenin, (estrogenic effects), cytochrome P4501A (CYP1A, dioxin-like compounds), superoxide dismutase (oxidative stress) and HSP70 (general stress)--were tested as markers of exposure to pollutants both in natural populations and in experimental treatments with model effectors. Analysis of fish from a metal-contaminated site in the Tunisian coast (Sfax) indicated that fish presenting spinal deformities (eight times more frequent at this site than in reference sites) showed increased levels of hepatic CYP1A mRNA levels compared to non-deformed fish from the same site or from the reference Louza site, suggesting a combined impact by metals and organic pollutants.

Influence of high temperature on cadmium-induced skeletal deformities in juvenile mosquitofish (Gambusia affinis).

The aim of this study was to assess the effect of high temperature on cadmium (Cd)-induced skeletal deformities in juvenile Mosquitofish, Gambusia affinis. For this purpose, 188 juveniles (1 day old) were equally divided into the control group, which was maintained in Cd-free water at 24 degrees C, and three treated groups exposed either to Cd (0.4 mg/l as Cd Cl(2)) at 24 degrees C, to high temperature (32 degrees C), or to Cd at 32 degrees C for 30 days.

Involvement of cd bioaccumulation in spinal deformities occurrence in natural populations of Mediterranean killifish.

The aim of this study was to investigate the possible influence of environmental exposure to cadmium (Cd) on the spinal deformities occurrence in the Mediterranean killifish, Aphanius fasciatus (Pisces: Cyprinodontidae). For this purpose, some indicators of skeletal bone mineralization, Cd, and calcium (Ca) concentrations in spinal column as well as bioaccumulation of Cd from the water and the sediment have been compared in normal and deformed fish collected from polluted (S1) and nonpolluted (S2) areas in the Gulf of Gabès in Tunisia. When compared to the normal fish, the deformed fish showed signs of spinal column demineralization such as significant decrease in the ash weight/dry weight ratio, percentage of nonorganic components content, and Ca concentration.

Association of spinal deformities with heavy metal bioaccumulation in natural populations of grass goby, Zosterisessor ophiocephalus Pallas, 1811 from the Gulf of Gabès (Tunisia).

The present study illustrates an analysis of spinal deformities associated with metal accumulation in natural populations of Zosterisessor ophiocephalus derived from polluted (S1) and unpolluted (S2) areas in the Gulf of Gabès in Tunisia. Three basic types of spinal deformities were detected: kyphosis, scoliosis and lordosis. These basic deformities frequently co-occur.