Kleinhans Kelsey L, Jackson Alicia R
Orthopaedic Biomechanics Laboratory, Department of Biomedical Engineering, University of Miami, 1251 Memorial Drive, MEA 219, Coral Gables, FL 33124-0621 e-mail:
Orthopaedic Biomechanics Laboratory, Department of Biomedical Engineering, University of Miami, 1251 Memorial Drive, MEA 207, Coral Gables, FL 33124-0621 e-mail:
J Biomech Eng. 2017 Mar 1;139(3). doi: 10.1115/1.4035537.
A nearly avascular tissue, the knee meniscus relies on diffusive transport for nutritional supply to cells. Nutrient transport depends on solute partitioning in the tissue, which governs the amount of nutrients that can enter a tissue. The purpose of the present study was to investigate the effects of mechanical strain, tissue region, and tissue composition on the partition coefficient of glucose in meniscus fibrocartilage. A simple partitioning experiment was employed to measure glucose partitioning in porcine meniscus tissues from two regions (horn and central), from both meniscal components (medial and lateral), and at three levels of compression (0%, 10%, and 20%). Partition coefficient values were correlated to strain level, water volume fraction, and glycosaminoglycan (GAG) content of tissue specimens. Partition coefficient values ranged from 0.47 to 0.91 (n = 48). Results show that glucose partition coefficient is significantly (p < 0.001) affected by compression, decreasing with increasing strain. Furthermore, we did not find a statistically significant effect of tissue when comparing medial versus lateral (p = 0.181) or when comparing central and horn regions (p = 0.837). There were significant positive correlations between tissue water volume fraction and glucose partitioning for all groups. However, the correlation between GAG content and partitioning was only significant in the lateral horn group. Determining how glucose partitioning is affected by tissue composition and loading is necessary for understanding nutrient availability and related tissue health and/or degeneration. Therefore, this study is important for better understanding the transport and nutrition-related mechanisms of meniscal degeneration.
膝关节半月板是一种几乎无血管的组织，其细胞营养供应依赖于扩散运输。营养物质的运输取决于组织中的溶质分配，而溶质分配决定了能够进入组织的营养物质的量。本研究的目的是探讨机械应变、组织区域和组织组成对半月板纤维软骨中葡萄糖分配系数的影响。采用简单的分配实验来测量猪半月板组织中两个区域（角部和中央）、两个半月板成分（内侧和外侧）以及三个压缩水平（0%、10%和20%）下的葡萄糖分配情况。分配系数值与组织标本的应变水平、水体积分数和糖胺聚糖（GAG）含量相关。分配系数值范围为0.47至0.91（n = 48）。结果表明，葡萄糖分配系数受压缩的显著影响（p < 0.001），随应变增加而降低。此外，在内侧与外侧比较时（p = 0.181）或中央与角部区域比较时（p = 0.837），我们未发现组织的统计学显著影响。所有组的组织水体积分数与葡萄糖分配之间均存在显著正相关。然而，GAG含量与分配之间的相关性仅在外侧角部组中显著。确定葡萄糖分配如何受组织组成和负荷的影响对于理解营养物质的可利用性以及相关组织的健康和/或退变至关重要。因此，本研究对于更好地理解半月板退变的运输和营养相关机制具有重要意义。
