Mechanical Characteristics of Electrospun Aligned PCL/PLLA Nanofibrous Scaffolds Conduct Cell Differentiation in Human Bladder Tissue Engineering
Mechanical Characteristics of Electrospun Aligned PCL/PLLA Nanofibrous Scaffolds Conduct Cell Differentiation in Human Bladder Tissue Engineering
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DOI：
10.1166/jnn.2013.7193
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发表时间：
2013-07-01
影响因子：
--
通讯作者：
Soleimani, Masoud
中科院分区：
文献类型：
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作者：
Ahvaz, Hana Hanaee;Mobasheri, Hamid;Soleimani, Masoud
静电纺PCL/PLLA纳米纤维支架的某些特性，如厚度、横截面密度、强度和弹性，可以定制以模拟膀胱组织工程所需的天然微环境。本实验研究了电纺丝支架培养的人膀胱平滑肌细胞（hBSMCs）的分化。排列的PCL/PLLA纤维支架，厚度约为100nm，用于实施不同的机械刺激。所构建的杂化排列PCL/PLLA支架的纵向杨氏模量（0.7 MPa）和横向杨氏模量（0.02 MPa）表现出静电纺纤维的各向异性取向。根据弹性极限应变，选择排列的支架，并使用SEM显微照片显示结果。在生理频率和0.1 Hz频率下施加机械力对hBSMCs的分化起着至关重要的作用。将支架拉伸至变形点以下2%，在基因转录水平上研究生理拉伸频率和0.1 Hz拉伸频率对hBSMCs种子支架的影响。施加0.1 Hz拉伸力使I/III/IV型胶原蛋白、弹性蛋白、α -平滑肌肌动蛋白和caldesmon的转录增加，而在生理速率下，上述基因均下调。另一方面，将人膀胱尿路上皮细胞（hBUCs）暴露在0.1 Hz的拉伸频率下，可促进某些功能标记物的转录，包括细胞角蛋白8和18。我们发现不同频率的机械力对hBSMCs和hBUCs的细胞外基质和收缩基因有不同的调节作用，这应该在组织工程策略中考虑。
Certain features of electrospun PCL/PLLA nanofibrous scaffolds such as thickness, cross section density, strength, and elastisity can be tailored to mimic the native microenvironment required for bladder tissue engineering. In this study the differentiation of human bladder smooth muscle cells (hBSMCs) cultured on electrospun scaffolds was studied. The scaffolds of aligned PCL/PLLA fibrous with a thickness of about 100 nm, used to implement different mechanical stimulation. Longitudinal (0.7 MPa) and traverse (0.02 MPa) Young's modulus of the constructed hybrid aligned PCL/PLLA scaffolds showed anisotropic orientation of the electrospun fibers. Based on the elastic limit strain, the aligned scaffolds were selected and SEM micrographs used to reveal the outcomes. The application of mechanical forces on seeded scaffolds at physiologic and 0.1 Hz frequencies played crucial role in the differentiation of hBSMCs. Scaffolds were stretched to 2% below the deformation point and the effects of the physiologic and 0.1 Hz stretching frequencies on hBSMCs seeded scaffolds were investigated at gene transcription level. The application of 0.1 Hz stretching forces increased transcriptions of collagen type I/III/IV, elastin, alpha-smooth muscle actin and caldesmon, while at physiologic rate, all of the mentioned genes were down-regulated. On the other hand, exposing human bladder urothelial cells (hBUCs) to 0.1 Hz stretching frequencies promoted transcription of certain functional markers including cytokeratin 8 and 18. We found that mechanical forces with different frequencies exert different regulatory effects on extracellular matrices and contractile genes in hBSMCs and hBUCs that should be considered in tissue engineering strategies.