Biochemistry and Molecular Biology Program, University of Texas Rio Grande Valley, Brownsville, TX, USA.
Biochemistry and Molecular Biology Program, University of Texas Rio Grande Valley, Brownsville, TX, USA; School of Integrative Biological and Chemical Sciences, University of Texas Rio Grande Valley, Brownsville, TX, USA; School of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, Brownsville, TX, USA.
Comp Biochem Physiol C Toxicol Pharmacol. 2023 Oct;272:109710. doi: 10.1016/j.cbpc.2023.109710. Epub 2023 Jul 31.
Extensive agricultural activities to feed the growing population are one major driving force behind aquatic pollution. Different types of pesticides are used in farmlands to increase crop production and wash up into water bodies. Glyphosate-based herbicide Roundup® is one of the most used pesticides in the United States; however, its effects on teleost species are still poorly understood. This study focused on the effects of environmentally relevant concentrations of Roundup exposure (low- and high-dose: 0.5 and 5 μg/L for 2-week) on Na/K-ATPase (NKA, a biomarker for sodium‑potassium ion pump efficacy), cytochrome P450-1A (CYP1A, a monooxygenase enzyme), 2,4-dinitrophenyl protein (DNP, a biomarker for protein oxidation), 3-nitrotyrosine protein (NTP, a biomarker for protein nitration), superoxidase dismutase (SOD, an antioxidant enzyme), catalase (CAT, an antioxidant enzyme) expressions, and cellular apoptosis in the gills of goldfish. Histopathological and in situ TUNEL analyses showed widespread tissue damage, including lamellar fusion, loss of gill architecture, club shape of primary lamellae, mucous formation, and distortion in the epithelium layer, as well as apoptotic nuclei in gills. Immunohistochemical and qRT-PCR analyses provided insights into the expressions of molecular indicators in gills. Fish exposed to Roundup exhibited a significant (P < 0.05) downregulation of NKA expression in gills. Additionally, we observed upregulation of CYP1A, DNP, NTP, SOD, and CAT expressions in the gills of goldfish. Overall, our results suggest that exposure to Roundup causes disruption of gill architecture, induces protein oxidation/nitration and cellular apoptosis, and alters prooxidant-antioxidant homeostasis in tissues, which may lead to reduced fitness and survivability of teleost species.
为了满足不断增长的人口的需求，农业活动日益广泛，这是造成水环境污染的主要驱动力之一。为了提高作物产量，不同类型的农药被应用于农田，最终这些农药会被冲刷到水体中。草甘膦类除草剂农达（Roundup®）是美国使用最广泛的农药之一；然而，其对硬骨鱼类的影响仍知之甚少。本研究聚焦于环境相关浓度的农达暴露（低剂量和高剂量：0.5 和 5μg/L，暴露 2 周）对金鱼鳃组织钠钾-ATP 酶（NKA，一种钠离子钾离子泵功能的生物标志物）、细胞色素 P450-1A（CYP1A，一种单加氧酶）、2,4-二硝基苯蛋白（DNP，一种蛋白质氧化的生物标志物）、3-硝基酪氨酸蛋白（NTP，一种蛋白质硝化的生物标志物）、超氧化物歧化酶（SOD，一种抗氧化酶）、过氧化氢酶（CAT，一种抗氧化酶）表达以及鳃细胞凋亡的影响。组织病理学和原位末端转移酶标记（TUNEL）分析显示，广泛的组织损伤，包括鳃片融合、鳃结构丧失、初级鳃片棒状化、黏液形成以及上皮层扭曲，以及鳃组织中的凋亡核。免疫组织化学和 qRT-PCR 分析提供了鳃组织中分子标志物表达的见解。暴露于农达的金鱼的 NKA 表达显著下调（P<0.05）。此外，我们观察到 CYP1A、DNP、NTP、SOD 和 CAT 在金鱼鳃中的表达上调。总的来说，我们的研究结果表明，暴露于农达会破坏鳃的结构，诱导蛋白质氧化/硝化和细胞凋亡，并改变组织中的氧化应激平衡，这可能导致硬骨鱼类的适应能力和存活能力降低。
