The cardiovascular toxicity of triadimefon in early life stage of zebrafish and potential implications to human health☆
Graphical abstract
Introduction
Triadimefon[TF:1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)-2-butanone] is a registered broad-spectrum systemic sterol biosynthesis-inhibiting fungicide, which is extensively used to control rusts, mildews, fungal pests on fruits, vegetables, and ornamentals for more than two decades in China, and has a high solubility, strong stability and long half-life in water (Li et al., 2016, Liu et al., 2011). When fungicides are appropriately and scientifically utilized, they do not produce any serious health and environmental problems. However safety recommendations are not always followed, and undesirable high levels of residues are still detected in water, soils and food (Kong et al., 2016). It had been proved that high levels of TF residues were detected in soils, water and target agricultural products. For example, Papis and colleagues have reported that TF could be moderately absorbed in soils and hence maybe very mobile in the aquatic environment (Papis et al., 2006) and have been detected in water nearly 0.922 mg/L (Watschke et al., 2000). Furthermore, recent report showed that different pesticides were found in jujube ranged from 59.4 mg/kg to 2945.0 mg/kg, of which TF was found at a concentration of 1.0 mg/kg in fruits and 94.5 mg/kg in jujube soil (Liu et al., 2016a, Liu et al., 2016b), indicating that increased accumulation of pesticides in soil, water, and agricultural products pose serious threats to human health because of its wide application in agriculture and dietary intake through food consumption.
The toxicity of TF have been reported by many studies. For example, several eco-toxicology studies have indicated that triazole fungicides were highly toxic to a number of nontarget organisms (Groppelli et al., 2005, Menegola et al., 2005). TF was suspected of having teratogenic potential on the basis of FETAX (Frog Embryo Teratogenesis Assay-Xenopus) analysis. For example, Groppelli and colleagues reported teratogenic effects in Xenopus after exposure of triazoles at the neurula stage, at the level of cartilages and muscles of the 1st and 2nd branchial arches (Groppelli et al., 2005). In addition, two previous studies reported that TF could alter thyroid hormone levels and related gene expression in zebrafish (Liu et al., 2011) and in Xenopus laevis tadpoles (Li et al., 2016) in the early life stage, respectively. Recent study also found that TF may have endocrine-disrupting effects on lizards (E.argus) by acting sensitively on sex steroid hormones and steroidogenic-related genes. In animal test, triazoles can specifically affect branchial development in rats when exposure was performed during neurulation phases (Menegola et al., 2000, Menegola et al., 2001) as well as thyroid tumors in rats and liver tumors in rats and mice (Wolf et al., 2006). Moreover, an increasing number of investigations also proved that TF was a type of cytochrome p450 enzyme inhibitor (Li et al., 2017). TF may have reproductive toxicity to animals and even human beings (Vinggaard et al., 1999, Vinggaard et al., 2000, Chu et al., 2016), which was related to its influence by blocking the synthesis of 17 β-estradiol (E2) from testosterone (Brande-Lavridsen et al., 2008).
However, all of the above toxicity focused on neurotoxicity, hepatotoxicity, reproduction toxicity, developmental toxicity, and endocrine-disrupting effects. There is no cardiovascular toxicity information available. According to news report (The news website, 2016), cardiovascular disease, which was produced by genetic factors and environmental factors as well as a combination of both of these factors, was a global public health problem with a high mortality and case fatality, and multiplies the risk for a number of complications and huge medical costs. Given the increased accumulation of TF in soil, water, and food, potential cardiovascular disease risk require desperately to be evaluated, particularly to pesticide suicides population, occupational population (farmers, retailers and pharmaceutical workers), and special population (young children and infants, pregnant women, older people, and those with compromised immune systems) who are at a greater risk. Sekhotha et al. (2016) reported that there was a close relationship between pesticides and cardiovascular diseases. But, adverse effects of TF on the cardiovascular system is largely unknown. Therefore, in the present study, we aimed to evaluate systematically and comprehensively if TF exposure produce the risk of cardiovascular disease.
However, how to find a good and reliable animal model system to study pesticides exposure-cardiovascular effects, clarify the toxic mechanism, and explore strategies to mitigate those adverse effects is an urgent problem to resolve. Thanks to an almost entirely sequenced genome and high conservation of gene function and many molecular pathways compared with humans (Zon and Peterson, 2005, Bakkers, 2011), the zebrafish (Danio rerio) has emerged as an invaluable and highly informative vertebrate model system for studying substance toxicity on development, particularly on the development of cardiovascular system. This transparent vertebrate offers numerous compelling experimental advantages for evaluating toxic effects not found in other model systems (Sarmah and Marrs, 2016). A number of laboratories have employed the zebrafish to investigate the toxic effects of model chemicals released into the environment on the development of cardiovascular system, including nanoparticles, pesticides and various organic pollutants (Asharani et al., 2011, Belair et al., 2001, Chakraborty et al., 2016, Gerlach et al., 2014, Henry et al., 1997, King-Heiden et al., 2012, Teraoka et al., 2002, McGee et al., 2013, Zhang et al., 2013). These studies highlighted the suitability of the zebrafish as an excellent model to study human cardiovascular diseases (Bakkers, 2011).
In zebrafish, the heart is the first organ to develop and function and a beating heart forms by 22 hpf. By 48 hpf, the cardiovascular system is fully functional and exhibits a complex repertoire of ion channels and metabolic processes (Thisse and Zon, 2002).
Herein, in this study, 48 hpf zebrafish embryos were employed as the test organism, and the effects of TF on the cardiovascular system were studied systematically including malformation assessment (pericardial edema, circulation defects, hemorrhage, thrombogenesis, SV-BA distance and histopathology) and function assessment (heart rate, atria/ventricular ratio and cardiac output). Previous studies reported that Ca-dependent signaling are associated with heart failure, and they can alter the expression of some key Ca regulatory proteins involved in excitation-contraction coupling and their regulation by kinases and phosphatases (Bers and Guo, 2005, Kim et al., 2008). In addtion, Ca2+-ATPase is responsible for the regulation of Ca2+ uptake into the sarcoplasmic reticulum (Xu et al., 2009). Furthermore, troponin complex is a component of cardiac muscle thin filaments, and is often utilized in medicine as a target for some cardiotonic drugs used in the treatment of heart failure (Katrukha, 2013). To get an insight into the possible mechanisms of TF on cardiovascular system of zebrafish, so we performed the transcriptional profiles analysis of genes related to calcium signaling pathway and cardiac muscle contraction. Our results obtained here may provide information for TF-exposure cardiovascular disease risk, particularly for better pesticide poisoning treatments, occupational disease prevention, and providing theoretical foundation for risk management measures.
Section snippets
Chemicals
96% triadimefon was bought from Jiangsu Sword Agrochemicals Co., Ltd. Stock solutions were prepared in 100% dimethyl sulfoxide (DMSO; Amresco, Solon, OH,USA) and stored in the dark at 4 °C. 4% paraformaldehyde in phosphate-buffered saline was brought from Aladdin holdings (group) Co., Ltd (Shanghai, China). O-dianisidine was obtained from Sigma (St. Louis, MO, USA). Trizol reagent, reverse transcriptase kit and the SYBR Green system were purchased from Takara (Dalian, China).
Zebrafish husbandry
Wild-type AB strain
MNLC, LC10 and LC50
The mortality of embryos in each group at the end of exposure time (24 h) was recorded. Then TF-induced zebrafish mortality curve, which was presented in Fig. 1, was fitted in Origin 9.0. On the basis of mortality curves, MNLC, LC10 and LC50 of TF were estimated and calculated as 37.4, 42.5 and 47.2 μg/mL, respectively. Therefore 1/4 MNLC (9.4 μg/mL), 1/2 MNLC (18.7 μg/mL), MNLC (37.4 μg/mL), LC10 (42.5 μg/mL) and LC50 (47.2 μg/mL) were setup to study the cardiovascular toxicity of IF in
Discussion
Because of its widespread use, triadimefon (TF) is ubiquitous and accumulated in the environment, high levels of residues have been detected in soil, water bodie, and food (Liu et al., 2016a, Liu et al., 2016b, Papis et al., 2006, Watschke et al., 2000), which increases the risk to human health via food chain day-by-day, especially to pesticide suicides population, occupational population (farmers, retailers and pharmaceutical workers), and special population (young children and infants,
Conclusion
To the best of our knowledge, in this study, we was the first to explore systematically and comprehensively the detailed cardiovascular toxicity induced by TF using zebrafish model and found that TF induced serious and typical cardiovascular toxicity characterized by morphologic abnormity (pericardial edema, thrombosis and increased SV-BA distance) and functional failure (bradycardia and reduced cardiac output). Down-regulation of ATPase-related genes (atp2a1l, atp1b2b, atp1a3b), calcium
Conflict of interest statement
The authors declare that they have no competing interests.
Acknowledgments
This study was financially supported by Zhejiang Provincial Science & Technology Planning Project of China (no. 2015C02019) and Zhejiang Provincial Natural Science Foundation of China (no. Z12C140006).
References (62)
- et al.
Developmental exposures to an azole fungicide triadimenol at environmentally relevant concentrations cause reproductive dysfunction in females of medaka fish
Chemosphere
(2016) - et al.
Mono-substituted isopropylated triaryl phosphate, a major component of firemaster 550, is an AhR agonist that exhibits AhR-independent cardiotoxicity in zebrafish
Aquat. Toxicol.
(2014) - et al.
Teratogenic effects of two antifungal triazoles, triadimefon and triadimenol, on Xenopus laevis development: craniofacial defects
Aquat. Toxicol.
(2005) - et al.
Early life stage toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in zebrafish (Danio rerio)
Toxicol. Appl. Pharmacol.
(1997) - et al.
Effect of amitraz and chlordimeform on heart rate and pupil diameter in rats: mediated by alpha 2-adrenoreceptors
Toxicol. Appl. Pharmacol.
(1984) - et al.
Malachite green induces cardiovascular defects in developing zebrafish (Danio rerio) embryos by blocking VEGFR-2 signaling
Biochem. Biophys. Res. Commun.
(2009) - et al.
Effect of acetochlor on transcription of genes associated with oxidative stress, apoptosis, immunotoxicity and endocrine disruption in the early life stage of zebrafish
Environ. Toxicol. Pharmacol.
(2015) - et al.
Reproductive and developmental toxicity of dioxin in fish
Mol. Cell. Endocrinol.
(2012) - et al.
Processing factors of triadimefon and triadimenol in barley brewing based on response surface methodology
Food Control
(2016) - et al.
Waterborne exposure to triadimefon causes thyroid endocrine disruption and developmental delay in Xenopus laevis tadpoles
Aquat. Toxicol.
(2016)
Disruption of sex-hormone levels and steroidogenic-related gene expression on Mongolia Racerunner (Eremias argus) after exposure to triadimefon and its enantiomers
Chemosphere
Toxicity and cardiac effects of carbaryl in early developing zebrafish (Danio rerio) embryos
Toxicol. Appl. Pharmacol.
Changes of thyroid hormone levels and related gene expression in zebrafish on early life stage exposure totriadimefon
Environ. Toxicol. Pharmacol.
Pesticides in persimmons,jujubes and soil from China: residue levels, risk assessment and relationship between fruits and soils
Sci. Total. Environ.
Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) method
Methods
Antifungal triazoles induce malformations in vitro
Reprod. Toxicol.
Study on the common teratogenic pathway elicited by the fungicides triazole-derivatives
Toxicol. In Vitro
Screening of selected pesticides for inhibition of Cyp19 aromatase activity in vitro
Toxicol. in Vitro
Neuregulin-1/ErbB signaling: a druggable target for treating heart failure
Curr. Opin. Pharmacol.
Phenanthrene exposure produces cardiac defects during embryo development of zebrafish (Danio rerio) through activation of MMP-9
Chemosphere
Comparison of the toxicity of silver, gold and platinum nanoparticles in developing zebrafish embryos
Nanotoxicology
Zebrafish as a model to study cardiac development and human cardiac disease
Cardiovasc. Res.
Human cardiomyopathy mutations induce myocyte hyperplasia and activate hypertrophic pathways during cardiogenesis in zebrafish
Dis. Model. Mech.
Disruption of erythropoiesis by dioxin in the zebrafish
Dev. Dyn.
Calcium signaling in cardiac ventricular myocytes
Ann. N. Y. Acad. Sci.
Effects of prochloraz and ethinylestradiol on sexual development in Rana temporaria
J. Exp. Zool. Part A
Zebrafish: a complete animal model to enumerate the nanoparticle toxicity
J. Nanobiotechnol.
Analysis of left ventricular impedance in comparison with ultrasound images
Artif. Organs
Heart malformation is an early response to TCDD in embryonic zebrafish
Toxicol. Sci.
Low-dose exposure of silica nanoparticles induces cardiac dysfunction via neutrophil-mediated inflammation and cardiac contraction in zebrafish embryos
Nanotoxicology
Troponin T is essential for sarcomere assembly in zebrafish skeletal muscle
J. Cell Sci.
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This paper has been recommended for acceptance by Dr. Harmon Sarah Michele.