Department of Physiology and Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Department of Physiology and Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Microb Pathog. 2019 Jun;131:164-169. doi: 10.1016/j.micpath.2019.04.007. Epub 2019 Apr 9.
Bacterial diseases are one of the major problems in freshwater fish culture and have been linked to significant losses and high mortality rate. In this study, Nile tilapia Oreochromis niloticus was infected by Providencia rettgeri to evaluate the oxidative stress and antioxidant responses in the fish tissues. Juvenile Nile tilapia was divided into two groups, as follow: control (uninfected) and experimentally infected with 100 μL of P. rettgeri suspension containing 2.4 × 10 viable cells/fish, and the liver and kidney tissues were collected on days 7 and 14 post-infection (PI). Liver and kidney ROS and lipid peroxidation levels were high in infected fish on day 14 PI compared to control group, while superoxide dismutase activity was lower in liver (days 7 and 14 PI) and kidney (day 14 PI) compared to their respective control groups. Liver and kidney antioxidant capacity against peroxyl radicals, non-proteic, and proteic thiols levels was lower in infected tilapia on day 14 PI compared to control group. Based on these results, P. rettgeri infection may elicit oxidative damage via increased ROS production, decreased ROS elimination and inhibits enzymatic and non-enzymatic antioxidant defense systems; which may contribute directly to disease pathophysiology of infected animals.
细菌性疾病是淡水鱼类养殖中的主要问题之一，已导致重大损失和高死亡率。在这项研究中，罗非鱼 Oreochromis niloticus 被雷特氏普罗威登斯菌感染，以评估鱼类组织中的氧化应激和抗氧化反应。幼年尼罗罗非鱼分为两组：对照组（未感染）和实验组，用含有 2.4×10 个活菌/鱼的 100µL P. rettgeri 悬浮液感染，分别在感染后第 7 天和第 14 天采集肝脏和肾脏组织。与对照组相比，感染鱼在第 14 天 PI 的肝脏和肾脏 ROS 和脂质过氧化水平较高，而超氧化物歧化酶活性在肝脏（第 7 天和第 14 天 PI）和肾脏（第 14 天 PI）中均低于各自的对照组。与对照组相比，感染罗非鱼在第 14 天 PI 的肝脏和肾脏对过氧自由基、非蛋白和蛋白巯基的抗氧化能力较低。基于这些结果，P. rettgeri 感染可能通过增加 ROS 产生、减少 ROS 消除以及抑制酶和非酶抗氧化防御系统来引发氧化损伤；这可能直接导致感染动物的疾病病理生理学。
