This study aims to investigate how biochemical composition in subchondral bone (SB) relates to the sulfated glycosaminoglycan (sGAG) content of articular cartilage (AC) in the knee joint of guinea pigs from the early to moderate osteoarthritis (OA). Male Dunkin Hartley strain guinea pigs were grouped according to age (1, 3, 6, and 9 months, with 10 guinea pigs in each group). The biochemical properties of the AC and SB in the tibial plateau of the guinea pigs were determined through histology and Raman spectroscopy, respectively. Furthermore, the microstructures of the SB were investigated using micro-computed tomography (micro-CT) and histology. Increased thickness and bone mineral density (BMD) and decreased porosity were observed in the subchondral plate (SP) with the progression of spontaneous OA, accompanied by a decreasing trend in sGAG integrated optical density (IOD) of AC. Compared with the changes in the microstructure of subchondral bone, the content of sGAG was more correlated to the changes in the mineral/matrix ratio of subchondral bone. The mineralization of the matrix was significantly correlated to the content of sGAG compared with crystallinity/maturity and Type B carbonate substitution. PO₄³⁻ ν1/Amide III was more correlated to the content of sGAG than PO₄³⁻ ν1/Amide I, PO₄³⁻ ν1/CH₂ wag during the progression of spontaneous osteoarthritis. This study demonstrated that the mineralization of subchondral bone plays a crucial role in the pathogenesis of OA. Future studies may access to the mineralization of subchondral bone in addition to its microstructure in the study for pathogenesis and early diagnosis of osteoarthritis.

本研究旨在研究早期至中度骨关节炎 (OA) 豚鼠膝关节软骨下骨 (SB) 的生化成分与硫酸化糖胺聚糖 (sGAG) 含量之间的关系。雄性 Dunkin Hartley 品系豚鼠按年龄分组（1、3、6 和 9 个月，每组 10 只豚鼠）。分别通过组织学和拉曼光谱测定了豚鼠胫骨平台中 AC 和 SB 的生化特性。此外，使用显微计算机断层扫描 (micro-CT) 和组织学研究了 SB 的微观结构。随着自发性 OA 的进展，在软骨下板 (SP) 中观察到增加的厚度和骨矿物质密度 (BMD) 以及减少的孔隙率，伴随着AC的sGAG集成光密度（IOD）的下降趋势。与软骨下骨微观结构的变化相比，sGAG的含量与软骨下骨矿物质/基质比的变化更相关。与结晶度/成熟度和 B 型碳酸盐取代相比，基质的矿化与 sGAG 的含量显着相关。采购订单₄ ^3- ν1/酰胺三获得更相关的sGAG含量比PO ₄ ^3- ν1/酰胺I，PO ₄ ^3- ν1/ CH ₂ WAG自发骨关节炎的进展期间。该研究表明，软骨下骨的矿化在 OA 的发病机制中起着至关重要的作用。未来的研究可能会在骨关节炎的发病机制和早期诊断研究中获得软骨下骨的矿化以及其微观结构。