Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, 625014, China.
Biol Trace Elem Res. 2011 Dec;144(1-3):695-704. doi: 10.1007/s12011-011-9093-y. Epub 2011 Jun 14.
Previous studies showed that dietary manganese can increase the MnSOD mRNA expression in a dose-dependent manner in the heart of broilers. In order to explore the specific mechanism of the MnSOD expression induced by manganese, a model of MnSOD expression was developed with primary cultured broiler myocardial cells. The objective of the present study was to investigate whether the model was working or not and to determine how manganese affects the expression of the enzyme in broiler myocardial cells in vitro. In experiment 1, various amount of manganese (0, 0.25, 0.5, 1, 2, and 4 mM) were added into the cultures for 24-h incubation to investigate MnSOD expression and for 0-, 6-, 12-, 24-, 36-, and 48-h incubation to measure the cell viability. In experiment 2, the most suitable Mn supplementation based on the results of experiment 1 was added into cultures for 6-, 12-, 24-, and 48-h incubation. The results showed that MnSOD mRNA, MnSOD protein, and MnSOD activity were induced by manganese in dose- and time-dependent manner. Manganese regulates MnSOD expression not only at transcriptional level but also at translational and/or posttranslational levels.
先前的研究表明，膳食锰以剂量依赖的方式增加肉鸡心脏中 MnSOD mRNA 的表达。为了探索锰诱导 MnSOD 表达的具体机制，我们用原代培养的肉鸡心肌细胞建立了 MnSOD 表达模型。本研究的目的是探讨该模型是否有效，并确定锰在体外如何影响肉鸡心肌细胞中酶的表达。在实验 1 中，将不同剂量的锰（0、0.25、0.5、1、2 和 4 mM）加入培养物中进行 24 小时孵育，以研究 MnSOD 的表达，并进行 0、6、12、24、36 和 48 小时孵育，以测量细胞活力。在实验 2 中，根据实验 1 的结果，加入最适的锰补充剂进行 6、12、24 和 48 小时孵育。结果表明，锰以剂量和时间依赖的方式诱导 MnSOD mRNA、MnSOD 蛋白和 MnSOD 活性的表达。锰不仅在转录水平上调节 MnSOD 的表达，而且在翻译和/或翻译后水平上也调节 MnSOD 的表达。
