Elgawish Rania A, Yoshimura Yukinori, Isobe Naoki
Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8528, Japan.
Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt.
J Poult Sci. 2018;55(1):70-77. doi: 10.2141/jpsa.0170054. Epub 2017 Jul 25.
Microcystins (MCs) are included in drinking water and a family of cyclic heptapeptide hepatotoxins that have been implicated in the impairment of liver function in various animals. There is scarce information on the effect of MCs on cytokines and apoptotic gene expression and on whether MCs can induce inflammation and apoptosis in avian hepatic tissue. This study investigated the expression of genes related to proinflammatory interleukins, apoptosis, and antioxidant function in chicken liver tissues cultured in the presence of different doses of microcystin-leucine-arginine (MC-LR). Livers were collected from five hens and liver slices were placed in sterile tubes containing Dulbecco's medium supplemented with 0, 1, 10, or 100 ng/mL of MC-LR. After 6 h of cultivation, total RNA was extracted and quantitative PCR analysis was performed for interleukin genes (, and ), , an apoptotic gene (), and genes involved in antioxidant function ([catalase [ ], glutathione peroxidase [ ], and superoxide dismutase []). Liver tissues in each group were fixed for histopathology. MC-LR downregulated the mRNA levels of , and as compared to the control (0 ng/mL) in dose-dependent patterns; however, the differences were not significant. The expression of in liver tissues exposed to 100 ng/mL of MC-LR was significantly (<0.05) lower than that in tissues exposed to 1 ng/mL. In contrast, MC-LR upregulated the mRNA expression of and genes involved in antioxidant function in the liver tissues after 6 h, without the difference reaching statistical significance. Hepatocytes showed vacuolar degeneration and focal necrosis according to the dose of MC-LR. This study highlighted the risk of low doses of MC-LR in chicken liver. Moreover, MC-LR could modulate the transcriptional patterns of at least in liver-tissue culture of chicken after 6 h of exposure.
微囊藻毒素（MCs）存在于饮用水中，是一类环状七肽肝毒素，与多种动物的肝功能损害有关。关于MCs对细胞因子和凋亡基因表达的影响以及MCs是否能诱导禽类肝组织炎症和凋亡的信息很少。本研究调查了在不同剂量的微囊藻毒素 - 亮氨酸 - 精氨酸（MC - LR）存在下培养的鸡肝组织中促炎白细胞介素、凋亡和抗氧化功能相关基因的表达。从五只母鸡收集肝脏，将肝切片置于含有补充了0、1、10或100 ng/mL MC - LR的杜尔贝科培养基的无菌管中。培养6小时后，提取总RNA，并对白细胞介素基因（ 、 和 ）、凋亡基因（ ）以及参与抗氧化功能的基因（过氧化氢酶[ ]、谷胱甘肽过氧化物酶[ ]和超氧化物歧化酶[ ]）进行定量PCR分析。每组肝组织固定用于组织病理学检查。与对照组（0 ng/mL）相比，MC - LR以剂量依赖方式下调了 、 和 的mRNA水平；然而，差异不显著。暴露于100 ng/mL MC - LR的肝组织中 的表达显著（<0.05）低于暴露于1 ng/mL的组织。相反，MC - LR在6小时后上调了肝组织中 和参与抗氧化功能的基因的mRNA表达，但差异未达到统计学意义。肝细胞根据MC - LR的剂量表现出空泡变性和局灶性坏死。本研究强调了低剂量MC - LR对鸡肝脏的风险。此外，暴露6小时后，MC - LR可在鸡肝组织培养中调节至少 的转录模式。
