Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
Environ Pollut. 2021 Feb 1;270:116055. doi: 10.1016/j.envpol.2020.116055. Epub 2020 Nov 23.
We investigated the in vitro effects of pyriproxyfen on ionic balance in the testis of the zebrafish by measuring Ca influx. In vivo pyriproxyfen treatment was carried out to study oxidative stress, and conduct morphological analysis of the testis and liver. Whole testes were incubated in vitro with/without pyriproxyfen (10, 10 or 10 M; 30 min) and Ca influx determined. To study pyriproxyfen's mechanism of action, inhibitors/activators of ionic channels or pumps/exchangers, protein kinase inhibitors or a calcium chelator were added 15 min before the addition of Ca and pyriproxyfen. We evaluated the in vivo effects of 7 day exposure to waterborne pyriproxyfen (10 M) on reactive oxygen species (ROS) formation, lipid peroxidation, and reduced glutathione content (GSH), glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) and γ-glutamyltransferase (GGT) activity. Morphological analyses of the testis and liver were carried out after in vivo exposure of D. rerio to pyriproxyfen. Pyriproxyfen increased Ca influx by opening the voltage-dependent T-type channels (T-type VDCC), inhibiting sarco/endoplasmic reticulum Ca-ATPase (SERCA) and the NCX exchanger (forward mode) and by mobilizing calcium from stores. The involvement of potassium channels and protein kinase C (PKC) was also demonstrated in pyriproxyfen-induced intracellular calcium elevation. In vivo pyriproxyfen treatment of D. rerio increased lipid peroxidation, decreased GSH content and increased GST activity in testes, in addition to increasing the number and size of spermatogonia cysts and inducing hepatocyte basophilia and dilation of blood vessels in the liver. The toxicity of pyriproxyfen is mediated by calcium overload, increased lipid peroxidation, and a diminished antioxidant capacity in the testis, due to GSH depletion, and altered spermatogenesis. The development of high basophilia in the liver suggests that pyriproxyfen may have estrogenic activity, possibly acting as an endocrine-disruptor. These findings indicate that these alterations may contribute to pyriproxyfen toxicity and spermatogenesis disruption.
我们通过测量 Ca 流入来研究了吡丙醚对斑马鱼睾丸离子平衡的体外影响。进行体内吡丙醚处理以研究氧化应激，并对睾丸和肝脏进行形态分析。将整个睾丸在有/无吡丙醚（10、10 或 10 -M；30 分钟）的情况下在体外孵育，并确定 Ca 流入。为了研究吡丙醚的作用机制，在添加 Ca 和吡丙醚之前 15 分钟添加离子通道或泵/交换器的抑制剂/激活剂、蛋白激酶抑制剂或钙螯合剂。我们评估了 7 天暴露于水基吡丙醚（10 -M）对活性氧 (ROS) 形成、脂质过氧化和还原型谷胱甘肽含量 (GSH)、谷胱甘肽 S-转移酶 (GST)、超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT) 和γ-谷氨酰转肽酶 (GGT) 活性的体内影响。在斑马鱼体内暴露于吡丙醚后，对睾丸和肝脏进行形态分析。吡丙醚通过打开电压依赖性 T 型通道 (T 型 VDCC)、抑制肌浆/内质网 Ca-ATP 酶 (SERCA) 和 NCX 交换器（正向模式）以及从储存中动员钙来增加 Ca 流入。钾通道和蛋白激酶 C (PKC) 的参与也证明了吡丙醚诱导的细胞内钙升高。体内吡丙醚处理斑马鱼增加了睾丸的脂质过氧化、GSH 含量降低和 GST 活性增加，除了增加精原细胞囊肿的数量和大小外，还诱导了肝细胞嗜碱性和肝脏血管扩张。吡丙醚的毒性是通过钙超载、脂质过氧化增加和 GSH 耗竭导致抗氧化能力降低以及精子发生改变介导的。肝脏中高嗜碱性的发展表明吡丙醚可能具有雌激素活性，可能作为内分泌干扰物。这些发现表明，这些改变可能导致吡丙醚毒性和精子发生破坏。
