Fenobucarb induces heart failure and cerebral hemorrhage in zebrafish

Protective effect of N-(E)-p-coumaroyltyrosine on LPS-induced acute inflammatory injury and signaling pathway analysis

N-trans-p-coumaroyltyrosine (N-(E)-p-coumaroyltyrosine, NPCT), extracted and purified from Abri Mollis Herba, is an amino acid amide. The defense mechanism of NPCT against inflammatory response is still unknown. In this study, lipopolysaccharide (LPS)-induced zebrafish acute inflammatory injury model was established to observe the inhibitory effect of NPCT on the aggregation of inflammatory cells in the yolk sac of zebrafish, as well as the inhibitory effect of NPCT on inflammatory and gas signaling factors. Results show that NPCT could inhibit inflammatory cell infiltration in zebrafish yolk sac, the migration and aggregation of macrophages and neutrophils to the site of inflammation, and the release of Nitric Oxide (NO) and Reactive Oxygen Species (ROS) in zebrafish, indicating that NPCT could substantially significantly prevent the development of LPS-induced acute systemic inflammation. In addition, the analysis results of RNA-seq showed that in the model group versus the administered group, the differentially expressed genes were mainly enriched to inflammatory signaling pathways, such as the NOD-like receptor signaling pathway and Toll-like receptor signaling pathway, which were down-regulated in the administered group. The TLR4, MyD88, IRAK4, NF-κB, IκB, NLRP3, Caspase-1, ASC, IL-1β, and IL-6 genes were significantly different in the transcripts, and the overall trend of the qPCR results was consistent with the transcriptome sequencing results. Therefore, NPCT had a significant inhibitory effect on LPS-induced acute inflammatory injury in zebrafish, and its anti-inflammatory mechanism may be through the regulation of key genes on the NOD-like receptor signaling pathway and Toll-like receptor signaling pathway, thereby affecting the release of relevant inflammatory cytokines.

asb5a/asb5b Double Knockout Affects Zebrafish Cardiac Contractile Function

Ankyrin repeat and suppression-of-cytokine-signaling box (Asb) proteins, a subset of ubiquitin ligase E3, include Asb5 with six ankyrin-repeat domains. Zebrafish harbor two asb5 gene isoforms, asb5a and asb5b. Currently, the effects of asb5 gene inactivation on zebrafish embryonic development and heart function are unknown. Using CRISPR/Cas9, we generated asb5a-knockout zebrafish, revealing no abnormal phenotypes at 48 h post-fertilization (hpf). In situ hybridization showed similar asb5a and asb5b expression patterns, indicating the functional redundancy of these isoforms. Morpholino interference was used to target asb5b in wild-type and asb5a-knockout zebrafish. Knocking down asb5b in the wild-type had no phenotypic impact, but simultaneous asb5b knockdown in asb5a-knockout homozygotes led to severe pericardial cavity enlargement and atrial dilation. RNA-seq and cluster analyses identified significantly enriched cardiac muscle contraction genes in the double-knockout at 48 hpf. Moreover, semi-automatic heartbeat analysis demonstrated significant changes in various heart function indicators. STRING database/Cytoscape analyses confirmed that 11 cardiac-contraction-related hub genes exhibited disrupted expression, with three modules containing these genes potentially regulating cardiac contractile function through calcium ion channels. This study reveals functional redundancy in asb5a and asb5b, with simultaneous knockout significantly impacting zebrafish early heart development and contraction, providing key insights into asb5's mechanism.

Organophosphorus and carbamate pesticides: Molecular toxicology and laboratory testing

Population and food requirements are increasing daily throughout the world. To fulfil these requirements application of pesticides is also increasing. Organophosphorous (OP) and Organocarbamate (OC) compounds are widely used pesticides. These pesticides are used for suicidal purposes too. Both inhibit Acetylcholinesterase (AChE) and cholinergic symptoms are mainly used for the diagnosis of pesticide poisoning. Although the symptoms of the intoxication of OP and OC are similar, recent research has described different targets for OP and OC pesticides. Researchers believe the distinction of OP/OC poisoning will be beneficial for the management of pesticide exposure. OP compounds produce adducts with several proteins. There is a new generation of OP compounds like glyphosate that do not inhibit AChE. Therefore, it's high time to develop biomarkers that can distinguish OP poisoning from OC poisoning.

Zebrafish: A smart tool for heart disease research

The increasing prevalence of heart disease poses a significant threat to human survival and safety. However, the current treatments available for heart disease are quite limited. Therefore, it is of great importance to utilize suitable animal models that can accurately simulate the physiological characteristics of heart disease. This would help improve our understanding of this disease and aid in the development of new treatment methods and drugs. Zebrafish hearts not only exhibit similarities to mammalian hearts, but they also share ~70% of homologous genes with humans. Utilizing zebrafish as an alternative to costly and time-consuming mammalian models offers numerous advantages. Zebrafish models can be easily established and maintained, and compound screening and genetic methods allow for the creation of various economical and easily controlled zebrafish and zebrafish embryonic heart disease models in a short period of time. Consequently, zebrafish have become a powerful tool for exploring the pathological mechanisms of heart disease and identifying new effective genes. In this review, we summarize recent studies on different zebrafish models of heart disease. We also describe the techniques and protocols used to develop zebrafish models of myocardial infarction, heart failure, and congenital heart disease, including surgical procedures, forward and reverse genetics, as well as drug and combination screening. This review aims to promote the utilization of zebrafish models in investigating diverse pathological mechanisms of heart disease, enhancing our knowledge and comprehension of heart disease, and offering novel insights and objectives for exploring the prevention and treatment of heart disease.

Environmental exposure to triazole fungicide causes left-right asymmetry defects and contributes to abnormal heart development in zebrafish embryos by activating PPARγ-coupled Wnt/β-catenin signaling pathway

Triazole fungicides have been widely used all over the world. However, their potential ecological safety and health risks remain unclear, especially their cardiac developmental toxicity. This study systematically investigated whether and how triazole fungicides could activate peroxisome proliferative activity receptor γ (PPARγ) to cause abnormal heart development. Among ten triazole fungicides, difenoconazole (DIF) exhibited the strongest agonistic activity and caused severe pericardial edema in zebrafish embryos, accompanied by a reduction in heart rate, blood flow and cardiac function. In vitro transcriptomic profile implicated that DIF inhibited the Wnt signaling pathway, and in vivo DIF exposure significantly increased the phosphorylation of β-catenin (p = 0.0002) and altered the expression of related genes in zebrafish embryos. Importantly, exposure to DIF could activate PPARγ and inhibit the Wnt/β-catenin signaling pathway, which changed the size of Kupffer's vesicle (KV) (p = 0.02), altered the expression of left-right (LR) asymmetry-related genes, caused cardiac LR asymmetry defect, and eventually led to abnormal heart development. These findings provide evidence for potential developmental toxicity of triazole fungicides and highlight the necessity of assessing their ecological safety and human health risks.

Toxicity of single and combined 4-epianhydrotetracycline and cadmium at environmentally relevant concentrations on the zebrafish embryos (Danio rerio)

The combined pollution of antibiotics and heavy metals has attracted a worldwide attention in the recent years. 4-epianhydrotetracycline (EATC) is the major degradation product of tetracycline (TC), which has been detected frequently in environment and its concentration is even higher than TC under some circumstances. Cadmium (Cd) is a common heavy metal contaminant and has highly toxic to organisms, plants and humans even at low doses. In the present study, zebrafish (Danio rerio) embryo toxicity test was performed to investigate the single and combined effects of EATC and Cd on aquatic organisms. Exposure to EATC and Cd at environmentally relevant concentrations had a series of hazardous impacts on the embryonic development, including lethality, hatching rate, heart rate and teratogenic effects. Compared to the contaminant existed alone, combined pollution produced stronger toxicity, which appeared as the decreasing of heart rate and hatching rate, and the increasing of malformation of zebrafish embryos. After 96 h exposure, the reactive oxygen species (ROS) levels in zebrafish embryos were increased significantly, revealing that EATC-Cd co-exposure resulted in potential oxidative stress-induced damage. Acridine orange (AO) staining showed that combined exposure resulted in stronger cell apoptosis. The potential health risks of the combined pollution of EATC and Cd should be paid more attention to higher level vertebrates and humans.

Abrusamide H Impairs the Secretion of the Cytokines in RAW264.7 Cells and the Inflammatory Infiltration in Tail Transection-Induced Zebrafish

Abrus mollis Hance (Leguminosae) has a variety of biological activities, including anti-inflammatory, antioxidant, antibacterial, antiviral, and antitumor activities. However, the specific substances responsible for the anti-inflammatory effects are unknown. Abrusamide H (BJBS) is a truxillic acid derivative obtained from the leaves of Abrus mollis Hance and has potential anti-inflammatory effects. In this study, we aimed to estimate the potential effect and mechanism of BJBS in inflammation by establishing lipopolysaccharide (LPS)-stimulated RAW264.7 cells in vitro and an injured zebrafish tail fin in vivo. The RAW264.7 cells were treated with different concentrations of BJBS after LPS stimulation. The production of nitric oxide (NO) was detected by Griess reaction, and reactive oxygen species (ROS) were detected by an ROS assay kit. The levels of proinflammatory cytokines, including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and interleukin 18 (IL-18) were measured by ELISA. Results showed that BJBS at all concentrations inhibited the proliferation of RAW264.7 macrophages after LPS stimulation by cell counting kit-8 and the production of NO and ROS. In the BJBS treatment group, the levels of IL-6, TNF-α, IL-1β, and IL-18 decreased in a concentration-dependent manner. The results in vivo showed that no significant difference in the survival of zebrafish between the BJBS and blank groups and BJBS inhibited the migration and aggregation of zebrafish neutrophils in a dose-dependent manner in inflammation induced by tail transection-induced inflammation. In conclusion, BJBS inhibited the production of NO and ROS, decreased the levels of secreted IL-6, TNF-α, IL-1β, and IL-18, and reduced the migration and aggregation of zebrafish neutrophils.

Systemic Stereoselectivity Study of Fenobucarb: Environmental Behaviors in Greenhouse Vegetables, Fruits, Earthworms, and Soils and Its Cytotoxicity

Fenobucarb (2-sec-butylphenyl methylcarbamate, BPMC) is a potent carbamate pesticide with high insecticidal activity. In this study, the enantioselective accumulation of BPMC in earthworms (Eisenia foetida) and dissipation in cabbage, Chinese cabbage, strawberry, and soils were investigated. The samples were prepared using the QuEChERS method and analyzed using fast and sensitive chiral high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) analysis. The stereoselective accumulation of BPMC enantiomers revealed that S-(+)-BPMC was preferentially accumulated in earthworms rather than its antipode. However, the dissipation studies showed that S-(+)-BPMC degraded faster than the R-(-)-isomer in cabbage, Chinese cabbage, strawberry, and soils. Furthermore, the cytotoxic effect of BPMC enantiomers toward PC12 and N9 neuronal, A549 lung cancer, and MRC5 lung fibroblast cell lines was evaluated using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Compared with R-(-)- and rac-isomers, S-(+)-BPMC exhibited lower cytotoxicity in neuronal cells and a weaker proliferating effect on lung cancer and lung fibroblast cells. Altogether, the findings suggest the use of the pure S-(+)-enantiomer in agricultural management rather than the use of the racemate or the R-(-)-isomer, which might reduce the environmental risk.

Health risks of sulfentrazone exposure during zebrafish embryo-larvae development at environmental concentration

Knowledge about the negative effects and mechanism of sulfentrazone (SUL) on aquatic early life stages is still limited. Here we investigated the lethal and sub-lethal effects of SUL during zebrafish embryo-larvae development. Results demonstrated that the 96 h and 120 h-LC₅₀ of SUL to embryonic zebrafish was 2.02 mg/L, and the 30 d-LC₅₀ was 0.899 mg/L after embryos exposed to SUL for 30 d. High concentrations of SUL delayed yolk sac absorption, disordered the hatching and heart rate during zebrafish embryonic stage, while 0.0100-0.100 mg/L SUL had no phenotypic changes on embryonic development, but decreased the body weight of larvae after 30 d exposure. RNA-seq identified 321, 394 and 727 differentially expressed genes in larvae after embryos exposed to 0.0100 mg/L, 0.0400 mg/L and 0.400 mg/L SUL for 30 d, found that the transcriptional profiles involved in heart development and endocrine disruption were simultaneously influenced by different concentrations of SUL, such as adrenergic signaling in cardiomyocytes, cardiac muscle contraction, cell adhesion molecules and steroid biosynthesis. Biochemical analysis showed that SUL increased the levels of E₂, T₃ and TSH, induced the activities of mitochondrial complex IV, cytochrome c oxidase, Ca²⁺-ATPase, total Na⁺K⁺-ATPase and Ca²⁺Mg²⁺-ATPase, and decreased ATP formation after embryos exposed to SUL for 5 d and 30 d. Further comprehensive analysis demonstrated that SUL caused more significantly alteration on the transcript, level or activity of the key elements involved in heart development and endocrine disruption after 30 d exposure, indicated long-term SUL exposure might cause more negative effects on zebrafish at doses below the presumed no-observed-adverse-effect level during early life development. The results inferred the environmental concentration of SUL might cause potential cardiac and endocrine health risk in zebrafish later life stages, also facilitated a better understanding of the sub-lethal effects and molecular mechanism of SUL on aquatic organism.

Cardiotoxicity of sanguinarine via regulating apoptosis and MAPK pathways in zebrafish and HL1 cardiomyocytes

Sanguinarine, a plant phytoalexin, possesses extensive biological activities including antimicrobial, insecticidal, antitumor, anti-inflammatory and anti-angiogenesis effect. But its cardiotoxicity has rarely been studied. Here, we assess the cardiotoxicity of sanguinarine in vivo using larval zebrafish from 48 hpf to 96 hpf. The results show that sanguinarine caused severe malformation and the dysfunction of the heart including reductions of heart rate, red blood cell number, blood flow dynamics, stroke volume and increase of SV-BA distance, subintestinal venous congestion. Further studies showed that apoptosis in the zebrafish heart region was observed after sanguinarine exposure using TUNEL assay and AO staining method. In addition, the genes, such as sox9b, myl7, nkx2.5 and bmp10, which play crucial parts in the development and the function of the heart, were changed after sanguinarine treatment. caspase3, caspase9, bax and bcl2, apoptosis-related genes, were also altered by sanguinarine. Further studies were performed to study the cardiotoxicity in vitro using cardiomyocytes HL1 cell line. The results showed that remarkable increase of apoptosis and ROS level in HL1 cells were induced by sanguinarine. Moreover, the MAPK pathway (JNK and P38) were notably enhanced and involved in the cardiotoxicity induced by sanguinarine. Our findings will provide better understanding of sanguinarine in the toxic effect on heart.

Application and advantages of zebrafish model in the study of neurovascular unit

The concept of "Neurovascular Unit" (NVU) was put forward, so that the research goal of Central Nervous System (CNS) diseases gradually transitioned from a single neuron to the structural and functional integrity of the NVU. Zebrafish has the advantages of high homology with human genes, strong reproductive capacity and visualization of neural circuits, so it has become an emerging model organism for NVU research and has been applied to a variety of CNS diseases. Based on CNKI (https://www.cnki.net/) and PubMed (https://pubmed.ncbi.nlm.nih.gov/about/) databases, the author of this article sorted out the relevant literature, analyzed the construction of a zebrafish model of various CNS diseases，and the use of diagrams showed the application of zebrafish in the NVU, revealed its relationship, which would provide new methods and references for the treatment and research of CNS diseases.

Current overview and perspectives in environmentally friendly microextractions of carbamates and dithiocarbamates

Carbamates and dithiocarbamates are two classes of pesticides widely employed in the agriculture practice to control and avoid pests and weeds, hence, the monitoring of the residue of those pesticides in different foodstuff samples is important. Thus, this review presents the classification, chemical structure, use, and toxicology of them. Moreover, it was shown the evolution of liquid- and solid-phase microextractions employed in the extraction of carbamates and dithiocarbamates in water and foodstuff samples. The classification, operation mode, and application of the microextractions of liquid-phase and solid-phase used in their extraction were discussed and related to the analytical parameters and guidelines of green analytical chemistry.

Embryotoxic effects of Rovral® for early chicken (Gallus gallus) development

Rovral® is a fungicide used to control pests that affect various crops and little is known regarding its effects on embryonic development of amniotes. Thus, this study aimed to determine the influence of Rovral® during chicken organogenesis using acute in ovo contamination. Fertilized eggs were inoculated with different concentrations of Rovral® (100, 300, 500 or 750 µl/ml), injected into the egg's air chamber. After 7 days, embryos were examined for possible malformations, staging, weight and mortality. Subsequently, head, trunk, limbs and eyes were measured for morphometry and asymmetry. For blood analysis, eggs were treated with 300 µl/ml Rovral® and glucose, presence of micronuclei and erythrocyte nuclei abnormalities determined. Treatments with Rovral® affected the mortality rate in a concentration-dependent manner. LC₅₀ value was found to be 596 µl/ml which represents 397-fold higher than the recommended concentration for use. Rovral® produced several malformations including hemorrhagic, ocular and cephalic abnormalities. No significant changes were observed in body weight, staging, body measurements, symmetry and glucose levels of live embryos, which indicates this fungicide presents low toxicity under the analyzed conditions. Changes in erythrocyte nuclei were noted; however significant difference was observed only for presence of binucleated erythrocytes. It is important to point out that possibly more significant changes may have occurred at lower concentrations through chronic contamination. Therefore, caution is needed in the use of this fungicide, since it presents teratogenic and mutagenic potential.

Cardiotoxicity induced by Cochinchina momordica seed extract in zebrafish

Momordica cochinchinensis (Lour.) Spreng is an indigenous South Asian edible fruit, and seeds of Momordica cochinchinensis have been used therapeutically in traditional Chinese medicine. Previous studies have shown that M. cochinchinensis seed (Momordicae Semen) has various pharmaceutical properties such as antioxidant and anti-ulcer effects as well as contains secondary metabolites with potential anticancer activities such as triterpenoids and saponins. Recent studies reported that water extract and ethanol extract of M. cochinchinensi seed were tested on mammals using an acute toxic classic method as OECD guidelines 420. No matter injected intravenously or intramuscularly, animals died within several days. In this study, zebrafish embryos were exposed to various doses of Cochinchina momordica seed extract (CMSE) from 2 dpf (days post fertilization, dpf) to 3 dpf. CMSE-induced cardiotoxicity such as pericardial edema, cardiac apoptosis, increased ROS production, cardiac neutrophil infiltration, decreased blood flow velocity, and reduced expression of three marker genes of cardiac functions were found in zebrafish roughly in a dose-dependent manner. These results suggest that CMSE may induce cardiotoxicity through pathways involved in inflammation, oxidative stress, and apoptosis.

Ponatinib-induced ischemic stroke in larval zebrafish for drug screening

Conventional mammalian ischemic stroke models for drug screening are technically challenging, laborious and time-consuming. In this study, using Ponatinib as an inducer, we developed and characterized a zebrafish ischemic stroke model. This zebrafish ischemic stroke had the cerebral vascular endothelial injury, thrombosis, reduced blood flow, inflammation and apoptosis as well as the reduced motility. The zebrafish ischemic stroke model was validated with 6 known human therapeutic drugs of ischemic stroke (Aspirin, Clopidogrel, Naoxintong capsules, Edaravone, Xingnaojing injection, Shuxuening injection). The mRNA levels of the neovascularization-related gene (vegfaa) and vascular endothelial growth factor receptor gene (VEGFR), neurodevelopment related genes (mbp and α1-tubulin), brain-derived neurotrophic factor (BDNF) and glial cell derived neurotrophic factor (GDNF) were significantly downregulated; whereas apoptosis-related genes (caspase-3, caspase-7, caspase-9 and bax/bcl-2), and inflammatory factor genes (IL-1β, IL-6, IL-10, TNF-α and NF-κB) were remarkably upregulated in the model. These results suggest that the pathophysiology of Ponatinib-induced zebrafish ischemic stroke is similar to that of human ischemic stroke patients and this whole animal model could be used to study the complex cellular and molecular pathogenesis of ischemic stroke and to rapidly identify therapeutic agents.

Exposure to prothioconazole induces developmental toxicity and cardiovascular effects on zebrafish embryo

Prothioconazole is a fungicide that has been widely used in general agriculture and livestock husbandry. This study evaluated the acute toxicity of prothioconazole to zebrafish embryos by assessing their hatching rate and malformation when exposed to different concentrations of prothioconazole. The 96 h-LC₅₀ value of zebrafish embryos was 1.70 mg/L. Upon exposure to 0.85 mg/L, the mortality rate of the embryos significantly increased while their hatching rate decreased significantly. At prothioconazole concentrations higher than 0.43 mg/L, developmental morphologic abnormalities such as heart and yolk-sac edema, spine curvature, tail deformity, shortened body length and decreased eye area were observed. The heart rate of embryos decreased in a dose-dependent fashion during the exposure time. Prothioconazole exposure also resulted in increased rates of cardiac malformation detected by significant increase in the distance between the sinus venosus and bulbus arteriosus and the pericardium area. Moreover, the expression levels of genes related to cardiac development (amhc, vmhc, fli1, hand2, gata4, nkx2.5, tbx5 and atp2a2a) were significantly altered after exposure to prothioconazole. Indeed, this study revealed the adverse effects on the developmental and cardiovascular system of zebrafish embryo caused by prothioconazole. It further elucidated the risk of prothioconazole exposure to vertebrate cardiovascular toxicity. As such, it provides a theoretical foundation for pesticide risk management measures.

Evaluation of the Developmental Toxicity Induced by E804 in Zebrafish Embryos

E804, a derivative of indirubin, have multi-biological activities such as anticancer and anti-inflammatory activities, but little is known about its developmental toxicity. In this study, we investigated the toxicity of E804 on the developments of zebrafish embryos. Our results showed that E804 treatment caused a significant increase of the malformation rate compared with the control groups. Pericardial edema and curved body shape were the most morphological abnormalities observed in E804-treated group. The hatching rates and body length of the zebrafish larvae was significantly decreased in E804-treated groups. E804 also affect the development of heart, liver, phagocytes and vascular formation. Further studies showed that the level of reactive oxygen species was significantly increased. The activity of total superoxide dismutase decreased and the concentration of malondialdehyde were increased. Much more apoptotic cells were detected in E804-treated group, compared with the control. In addition, gene-expression results showed that the pathways of oxidative stress and apoptosis were provoked in E804 treated groups. Taken together, our findings will be helpful to understanding E804-induced developmental toxicity and the underlying mechanism.

Cardiotoxicity of forchlorfenuron (CPPU) in zebrafish (Danio rerio) and H9c2 cardiomyocytes

Forchlorfenuron (CPPU), as a plant growth regulator or herbicide/pesticide, is widely used in agriculture worldwide. It is adopted by most farmers due to its high efficacy for boosting size and improving the quality of fruit. However, CPPU was implicated in, and gained notoriety due to an incident of exploding watermelon that occurred in 2011. Subsequently, the wider community became aware of the potential risks it posed to living organisms and the ecosystem. In this study, we evaluated the effects of CPPU on the survival, cardiac morphology and function, as well as hematopoietic system, of zebrafish (Danio rerio). Notably, CPPU (2.5-12.5 μg/ml) induced cardiac morphology deformation, cardiac contractile dysfunction and erythrocyte reduction in zebrafish. Consistently, the mRNA expression levels of several cardiac and hematopoietic gene markers (myl7, gata4, mef2c, amhc, vmhc and gata1) were altered by CPPU treatment. In addition, CPPU caused cytotoxicity, cytoskeleton destruction and reduced corresponding proteins (Myl7, Gata4 and Mef2c) expression in H9c2 cardiomyocytes in vitro. Taken together, this study has identified the cardiotoxicity of CPPU in different experimental models and enhanced our understanding on the mechanism underlying the toxicity of CPPU to living organisms.