Dietary supplementation of inosine monophosphate promotes cellular growth of muscle and upregulates growth-related gene expression in Nile tilapia Oreochromis niloticus
Dietary supplementation of inosine monophosphate promotes cellular growth of muscle and upregulates growth-related gene expression in Nile tilapia Oreochromis niloticus
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DOI：
10.1016/j.aquaculture.2016.10.033
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发表时间：
2017-02-01
期刊：
影响因子：
4.5
通讯作者：
Kader, Md. Abdul
中科院分区：
文献类型：
--
作者：
Asaduzzaman, Md.;Ikeda, Daisuke;Kader, Md. Abdul
肌肉生长机制由不同的细胞和分子途径控制，膳食中核苷酸（nt）的补充可能在影响鱼类的这些途径中发挥重要作用。在本研究中，我们假设在尼罗罗非鱼幼鱼的饲料中添加一磷酸肌苷（IMP）可以促进细胞肌肉的生长，并上调生长相关基因的表达。在酪蛋白和鱼粉为基础的半纯化饲粮中分别添加0、0.1、02、0.4和0.8% IMP，配制5种等氮（40%粗蛋白质）和等热量（203 KJ/g饲粮）试验饲粮。将尼罗罗非鱼幼鱼（0.59 +/- 0.1 g）放养在15个容量为150 L的玻璃纤维池中，放置在一个简单的生物过滤器密闭系统中，放养密度为25尾/池。初始日投喂率为体重（BW）的10%，最终降至体重（BW）的5%，饲喂60 d。处理结果比较采用方差分析（α = 0.05）。在第60天（60 D），添加02-0.8% IMP的鱼的末重显著高于不添加IMP的鱼。60 D时，与0-0.1% IMP相比，02-0.8% IMP添加组肥厚肌纤维频率（直径级10 = 100）和肥厚肌纤维频率（直径级60 = 50 > / 60 μ m）均显著提高。双向方差分析结果显示，与不添加IMP的鱼相比，添加0.2 ~ 0.8% IMP的鱼的垂体GH、肝脏IGF-1和GHR-1以及肌肉特异性MyoD、myogenin和Pax7基因表达上调。然而，肝脏IGF-2和肌肉生长抑制素基因表达不受饮食处理的显著影响。实时荧光定量PCR数据还显示，在饲喂试验结束时（60 D），与初始期（1 D）相比，肌肉生长抑制素基因表达下调，其他所有基因表达上调。本研究结果表明，添加IMP可促进尼罗罗非鱼的肌肉增生和肥厚，并上调生长相关基因的表达，从而促进尼罗罗非鱼的肌肉生长。由此可见，IMP是一种很有潜力的饲料添加剂，添加>= 0.2%的IMP对尼罗罗非鱼的生长促进效果最好。相关性说明：-在大多数情况下，通过计算鱼的大小或重量的增加来分析鱼的生长。然而，鱼类/肌肉的生长是由不同的细胞和分子途径控制的，这在水产培养和营养研究中研究得很少。本试验旨在研究饲粮中添加肌苷对尼罗罗非鱼幼鱼细胞肌肉生长特性和主要生长相关基因（GH、GHR-1、IGFs、MRFs、Pax7和肌肉生长抑制素）表达的影响。这项研究将有助于了解特定营养或饮食改善鱼类生长或产量背后的原因。(C) 2016 Elsevier B.V.版权所有
Muscle growth mechanisms are controlled by different cellular and molecular pathways, and dietary supplementation of nucleotides (NTs) may play an important role to influence such pathways in fish. In this study, we hypothesized that dietary supplementation of inosine monophosphate (IMP) would enhance cellular muscle growth, and upregulate growth-related gene expression in juvenile Nile tilapia Oreochromis niloticus. Five isonitrogenous (40% crude protein) and isocaloric (203 KJ/g diet) test diets were formulated by supplementing 0, 0.1, 02, 0.4 and 0.8% IMP in casein and fishmeal based semi-purified diet. Triplicate groups of juvenile Nile tilapia (0.59 +/- 0.1 g) were stocked in 15 fiberglass tanks (150 L capacity), arranged in a simple biological filters based closed system, with stocking density of 25 individuals per tank. The feed was applied at a daily feeding rate of 10% body weight (BW) initially and reduced to 5% BW finally for 60 days. Treatments results were compared using ANOVA (alpha = 0.05). At 60th day (60 D), final body weight of fish fed with 02-0.8% IMP were significantly higher than that of fish fed without IMP supplemented diet. At 60 D, both the hyperplastic (diameter class 10 = urn) and hypertrophic (diameter class 60 = 50 > d 60 mu m) muscle fiber frequency were significantly higher in 02-0.8% IMP supplemented diets compared to 0-0.1% IMP supplemented diet. Two-way ANOVA result demonstrated that the pituitary GH, hepatic IGF-1 and GHR-1, and muscle-specific MyoD, myogenin and Pax7 gene expression were upregulated in fish fed with 0.2-0.8% IMP compared to the fish fed without IMP supplemented diet. However, hepatic IGF-2 and myostatin gene expression were not significantly affected by the dietary treatments. Real-time PCR data also demonstrated that myostatin gene expression was downregulated and all other gene expression were upregulated at the end of feeding trial (60 D) compared to the initial period (1 D). The results of the present study indicated that IMP supplementation enhanced the muscle growth by promoting hyperplasia and hypertrophy, and upregulating the growth-related gene expression in Nile tilapia. In conclusion, IMP is a potential feed additive and supplementation of >= 0.2% IMP is the most effective for enhancing growth of Nile Tilapia.Statement of relevance:- In most cases, fish growth was analyzed by calculating the increase in size or weight of fish. However, fish/muscle growth are controlled by different cellular and molecular pathways, which are poorly studied areas in aqua culture and nutritional studies. A research was conducted to investigate the effects of dietary supplementation of inosine monophosphate on: (1) cellular muscle growth characteristics, and (2) expression of major growth-related genes (GH, GHR-1, IGFs, MRFs, Pax7 and myostatin) in juvenile Nile tilapia. This research will help to understand the reason behind the improved growth or production of fish with a specific nutrient or diet. (C) 2016 Elsevier B.V. All rights reserved.