Fackler Nathan P, Donahue Ryan P, Bielajew Benjamin J, Amirhekmat Arya, Hu Jerry C, Athanasiou Kyriacos A, Wang Dean
Department of Orthopaedic Surgery, University of California, Irvine, Orange, CA, USA.
Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA, USA.
Cartilage. 2025 Sep;16(3):366-375. doi: 10.1177/19476035231214724. Epub 2023 Nov 29.
ObjectiveThe use of porcine animal models for cartilage injury has increased recently due to their similarity with humans with regard to cartilage thickness, limited intrinsic healing of chondral defects, and joint loading biomechanics. However, variations in the mechanical and biochemical properties of porcine hip articular cartilage among various tissue ages and weightbearing (WB) regions are still unknown. This study's aim was to characterize the mechanical and biochemical properties of porcine hip articular cartilage across various ages and WB regions.MethodsArticular cartilage explants were harvested from WB and non-weightbearing (NWB) surfaces of the femoral head and acetabulum of domesticated pigs () at fetal (gestational age: 80 days), juvenile (6 months), and adult (2 years) ages. Explants underwent compressive stress-relaxation mechanical testing, biochemical analysis for total collagen and glycosaminoglycan (GAG) content, and histological staining.ResultsJuvenile animals consistently had the highest mechanical properties, with 2.2- to 7.6-time increases in relaxation modulus, 1.3- to 2.3-time increases in instantaneous modulus, and 4.1- to 14.2-time increases in viscosity compared with fetal cartilage. Mechanical properties did not significantly differ between the WB and NWB regions. Collagen content was highest in the NWB regions of the juvenile acetabulum (65.3%/dry weight [DW]) and femoral head (75.4%/DW) cartilages. GAG content was highest in the WB region of the juvenile acetabulum (23.7%/DW) and the WB region of the fetal femoral head (27.5%/DW) cartilages. Histological staining for GAG and total collagen content followed the trends from the quantitative biochemical assays.ConclusionThis study provides a benchmark for the development and validation of preclinical porcine models for hip cartilage pathologies.
目的
由于猪在软骨厚度、软骨缺损的有限内在愈合能力以及关节负荷生物力学方面与人类相似，近年来猪动物模型在软骨损伤研究中的应用有所增加。然而，不同组织年龄和负重（WB）区域的猪髋关节软骨的力学和生化特性差异仍不清楚。本研究的目的是表征不同年龄和WB区域的猪髋关节软骨的力学和生化特性。
方法
从胎龄80天的胎儿、6个月大的幼年和2岁大的成年家猪（ ）的股骨头和髋臼的WB和非负重（NWB）表面采集关节软骨外植体。外植体进行压缩应力松弛力学测试、总胶原蛋白和糖胺聚糖（GAG）含量的生化分析以及组织学染色。
结果
幼年动物的力学性能始终最高，与胎儿软骨相比，松弛模量增加2.2至7.6倍，瞬时模量增加1.3至2.3倍，粘度增加4.1至14.2倍。WB和NWB区域之间的力学性能没有显著差异。胶原蛋白含量在幼年髋臼的NWB区域（65.3%/干重[DW]）和股骨头软骨（75.4%/DW）中最高。GAG含量在幼年髋臼的WB区域（23.7%/DW）和胎儿股骨头的WB区域（27.5%/DW）软骨中最高。GAG和总胶原蛋白含量的组织学染色遵循定量生化分析的趋势。
结论
本研究为髋关节软骨病理学临床前猪模型的开发和验证提供了一个基准。
