Bisphenol AF induces multiple behavioral and biochemical changes in zebrafish (Danio rerio) at different life stages

Antipsychotic drug-induced behavioral abnormalities in common carp: The potential involvement of the gut microbiota-brain axis

The effects of antipsychotic drugs on aquatic organisms have received widespread attention owing to their widespread use and continued release in aquatic environments. The toxicological effects of antipsychotics on aquatic organisms, particularly fish, are unexplored, and the underlying mechanisms remain unelucidated. This study aimed to use common carp to explore the effects of antipsychotics (olanzapine [OLA] and risperidone [RIS]) on behavior and the potential mechanisms driving these effects. The fish were exposed to OLA (0.1 and 10 μg/L) and RIS (0.03 and 3 μg/L) for 60 days. Behavioral tests and neurological indicators showed that exposure to antipsychotics could cause behavioral abnormalities and neurotoxicity in common carp. Further, 16 S rRNA sequencing revealed gut microbiota alteration and decreased relative abundance of some strains related to SCFA production after OLA and RIS exposure. Subsequently, a pseudo-sterile common carp model was successfully constructed, and transplantation of the gut microbiota from antipsychotic-exposed fish caused behavioral abnormalities and neurotoxicity in pseudo-sterile fish. Further, SCFA supplementation demonstrated that SCFAs ameliorated the behavioral abnormalities and neurological damage caused by antipsychotic exposure. To our knowledge, the present study is the first to investigate the effects of antipsychotics on various complex behaviors (swimming performance and social behavior) in common carp, highlighting the potential health risks associated with antipsychotic drug-induced neurotoxicity in fish. Although these results do not fully elucidate the mechanisms underlying the effects of antipsychotic drugs on fish behavior, they serve as a valuable initial investigation and form the basis for future research.

Tributyltin-induced oxidative stress causes developmental damage in the cardiovascular system of zebrafish (Danio rerio)

Tributyltin (TBT) can be used as an antifouling agent with anticorrosive, antiseptic and antifungal properties and is widely used in wood preservation and ship painting. However, it has recently been found that TBT can be harmful to aquatic organisms. In this study, to gain insight into the effects of TBT with respect to the development of the cardiovascular system in zebrafish embryos, zebrafish embryos were exposed to different concentrations of TBT solutions (0.2 μg/L, 1 μg/L, and 2 μg/L) at 2 h post-fertilization (hpf) TBT exposure resulted in decreased hatchability and heart rate, deformed features such as pericardial edema, yolk sac edema, and spinal curvature in zebrafish embryos, and impaired heart development. Expression of cardiac development-related genes (vmhc, myh6, nkx2.5, tbx5a, gata4, tbx2b, nppa) is dysregulated. Transgenic zebrafish Tg (fli1: EGFP) were used to explore the effects of TBT exposure on vascular development. It was found that TBT exposure could lead to impaired development of intersegmental vessels (ISVs), common cardinal vein (CCV), subintestinal vessels (SIVs) and cerebrovascular. The expression of vascular endothelial growth factor (VEGF) signaling pathway-related genes (flt1, flt4, kdr, vegfa) was downregulated. Biochemical indices showed that ROS and MDA levels were significantly elevated and that SOD and CAT activities were significantly reduced. The expression of key genes for prostacyclin synthesis (pla2, ptgs2a, ptgs2b, ptgis, ptgs1) is abnormal. Therefore, it is possible that oxidative stress induced by TBT exposure leads to the blockage of arachidonic acid (AA) production in zebrafish embryos, which affects prostacyclin synthesis and consequently the normal development of the heart and blood vessels in zebrafish embryos.

Mechanistic interplay of dual environmental stressors: Bisphenol-A and cadmium-induced ovarian follicular damage and hepatocyte dysfunction in vivo

This study investigates the individual and combined toxic effects of Bisphenol A (BPA) and Cadmium (Cd) in zebrafish, recognizing the complex mixture of pollutants organisms encounter in their natural environment. Examining developmental, neurobehavioral, reproductive, and physiological aspects, the study reveals significant adverse effects, particularly in combined exposures. Zebrafish embryos exposed to BPA + Cd exhibit synergistically increased mortality, delayed hatching, and morphological abnormalities, emphasizing the heightened toxicity of the combination. Prolonged exposure until 10 days post-fertilization underscores enduring effects on embryonic development. BPA and Cd induce oxidative stress, as evidenced by increased production of reactive oxygen species and lipid peroxidation. This oxidative stress disrupts cellular functions, affecting lipid metabolism and immune response. Adult zebrafish exposed to BPA and Cd for 40 days display compromised neurobehavioral functions, altered antioxidant defenses, and increased oxidative stress, suggesting potential neurotoxicity. Additionally, disruptions in ovarian follicle maturation and skeletal abnormalities indicate reproductive and skeletal impacts. Histological analysis reveals significant liver damage, emphasizing the synergistic hepatotoxicity of BPA and Cd. Molecular assessments further demonstrate compromised cellular defense mechanisms, synaptic function, and elevated cellular stress and inflammation-related gene expression in response to combined exposures. Bioaccumulation analysis highlights differential tissue accumulation patterns. In conclusion, this study provides comprehensive insights into the multifaceted toxicological effects of BPA and Cd in zebrafish, raising concerns about potential adverse impacts on environmental ecosystems and human health.

Frontier of toxicology studies in zebrafish model

Based on the 87 original publications only from quartiles 1 and 2 of Journal Citation Report (JCR) collected by the major academic databases (Science Direct, Web of Science, PubMed, and Wiley) in 2022, the frontier of toxicology studies in zebrafish model is summarized. Herewith, a total of six aspects is covered such as developmental, neurological, cardiovascular, hepatic, reproductive, and immunizing toxicities. The tested samples involve chemicals, drugs, new environmental pollutants, nanomaterials, and its derivatives, along with those related mechanisms. This report may provide a frontier focus benefit to researchers engaging in a zebrafish model for environment, medicine, food, and other fields.

Toxic Effects of Bisphenol AF Exposure on the Reproduction and Liver of Female Marine Medaka (Oryzias melastigma)

In recent years, bisphenol AF (BPAF) in aquatic environments has drawn attention to its ecological risks. This study aims to investigate the toxic effects of BPAF (188.33 μg/L) exposure for 30 days on female marine medaka (Oryzias melastigma). On the 10th and 30th day of exposure, the toxicity was evaluated using histological analysis of the liver and ovaries and the transcription levels of genes related to the antioxidant system, immune system, and hypothalamic-pituitary-gonadal (HPG) axis. Findings revealed that (1) BPAF exposure caused vacuolation, karyopyknosis and karyolysis in the liver of marine medaka, and the toxic impact augmented with duration; (2) exposure to BPAF for 10 days facilitated the growth and maturation of primary ova, and this exposure had a comparatively inhibitory effect after 30 days; (3) exposure to BPAF resulted in a biphasic regulation of the transcriptional abundance of genes involved in antioxidant and inflammatory response (e.g., il-8, cat), with an initial up-regulation followed by down-regulation. Additionally, it disrupted the transcriptional pattern of HPG axis-related genes (e.g., 3βhsd, arα). In conclusion, 188.33 μg/L BPAF can alter the expression levels of functionally related genes, impair the structural integrity of marine organisms, and pose a threat to their overall health.

Associations of exposure to bisphenol A and its substitutes with neurodevelopmental outcomes among infants at 12 months of age: A cross-sectional study

BACKGROUND

Bisphenol A (BPA) exposure has been linked to adverse childhood neurodevelopment, but little is known about whether BPA substitutes exposures are also related to childhood neurodevelopment.

OBJECTIVES

To investigate the associations of exposure to BPA and its substitutes with infant neurodevelopment at 12 months.

METHODS

A total of 420 infants at 12 months were included from the Laizhou Wan (Bay) Birth Cohort in Shandong, China. Urinary concentrations of BPA and its substitutes including bisphenol S (BPS), bisphenol B (BPB), bisphenol AF (BPAF), bisphenol AP (BPAP), bisphenol P (BPP) and bisphenol Z (BPZ) were measured. Developmental quotient (DQ) scores based on the Gesell Development Schedules (GDS) were used to evaluate infant neurodevelopment. The multivariable linear regression and weighted quantile sum (WQS) regression were applied to estimate the associations of exposure to individual bisphenols and their mixtures with DQ scores, respectively. Sex-stratified analyses were also performed.

RESULTS

BPA was detected in most infants (89.05%) and had the highest median concentration (0.709 ng/mL) among all bisphenols. BPA substitutes except BPZ were ubiquitous in infants' urine samples (>70%), and BPS showed the highest median concentration (0.064 ng/mL) followed by BPAP (0.036 ng/mL), BPAF (0.028 ng/mL), BPP (0.015 ng/mL) and BPB (0.013 ng/mL). In multivariable linear regression, only BPAF exposure was inversely associated with social DQ scores among all infants (β = -0.334; 95% CI: -0.650, -0.019). After sex stratification, this inverse association was significant in girls (β = -0.605; 95% CI: -1.030, -0.180). Besides, BPA exposure was negatively related to gross motor DQ scores in boys (β = -1.061; 95% CI: -2.078, -0.045). WQS analyses confirmed these results.

CONCLUSIONS

Our study suggests that bisphenol exposure during infancy may be associated with poor infant neurodevelopment, and BPAF as a commonly used BPA substitute contributing the most to this adverse association deserves more attention.