Soluble miniagrin enhances contractile function of engineered skeletal muscle
Soluble miniagrin enhances contractile function of engineered skeletal muscle
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DOI：
10.1096/fj.11-187575
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发表时间：
2012-02-01
期刊：
影响因子：
4.8
通讯作者：
Bursac, Nenad
中科院分区：
文献类型：
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作者：
Bian, Weining;Bursac, Nenad
神经聚集蛋白在骨骼肌的神经支配和成熟过程中发挥着多效性作用，但其对神经工程化肌肉收缩功能的具体影响尚不清楚。在这项研究中，新生大鼠骨骼肌成肌细胞培养的三维工程肌肉组织结构进行了处理与10纳米可溶性重组miniagrin和评估使用组织学，生物化学和功能测定。根据相对于肌源性分化阶段的治疗持续时间和起始时间，发现微农蛋白诱导抽搐和强直力幅度增加高达1.7倍。这种效果与2.3倍的上调后6天的抗肌萎缩蛋白基因表达聚集蛋白去除和增强乙酰胆碱受体（AChR）簇的形成，但没有改变细胞数量，肌球蛋白的表达，或细胞内Ca 2+处理的重要方面。在肌肉结构与内源性乙酰胆碱水平抑制的应用程序的α-NETA，miniagrin增加乙酰胆碱受体聚集和抽搐力的幅度，但未能改善细胞内的Ca 2+处理和增加强直抽搐比。总的来说，我们的研究表明，除了可以促进体内工程肌肉构建体整合的突触发生功能外，神经聚集蛋白还可以通过与内源性ACh不同的机制直接促进神经工程肌肉的收缩功能。Bian，W.，Bursac，N.可溶性微聚集蛋白增强工程化骨骼肌的收缩功能。FASEB J.26，955-965（2012）。www.fasebj.org
Neural agrin plays a pleiotropic role in skeletal muscle innervation and maturation, but its specific effects on the contractile function of aneural engineered muscle remain unknown. In this study, neonatal rat skeletal myoblasts cultured within 3-dimensional engineered muscle tissue constructs were treated with 10 nM soluble recombinant miniagrin and assessed using histological, biochemical, and functional assays. Depending on the treatment duration and onset time relative to the stage of myogenic differentiation, miniagrin was found to induce up to 1.7-fold increase in twitch and tetanus force amplitude. This effect was associated with the 2.3-fold up-regulation of dystrophin gene expression at 6 d after agrin removal and enhanced ACh receptor (AChR) cluster formation, but no change in cell number, expression of muscle myosin, or important aspects of intracellular Ca2+ handling. In muscle constructs with endogenous ACh levels suppressed by the application of alpha-NETA, miniagrin increased AChR clustering and twitch force amplitude but failed to improve intracellular Ca2+ handling and increase tetanus-to-twitch ratio. Overall, our studies suggest that besides its synaptogenic function that could promote integration of engineered muscle constructs in vivo, neural agrin can directly promote the contractile function of aneural engineered muscle via mechanisms distinct from those involving endogenous ACh.-Bian, W., Bursac, N. Soluble miniagrin enhances contractile function of engineered skeletal muscle. FASEB J. 26, 955-965 (2012). www.fasebj.org