糖皮质激素诱导大鼠膝关节软骨及软骨下骨的剂量相关组织病理学和骨重塑特征
Dose-related histopathology and bone remodeling characteristics of the knee articular cartilage and subchondral bone induced by glucocorticoids in rats.
作者信息
Chen Yan, Huang Lian-Fang, Zhu Jue-Xin
机构信息
Guangdong Key Laboratory for Research and Development of Natural Drugs, Guangdong Medical University, Zhanjiang, Guangdong 524023, P.R. China.
出版信息
Exp Ther Med. 2019 Jun;17(6):4492-4498. doi: 10.3892/etm.2019.7508. Epub 2019 Apr 19.
The aim of the current study was to investigate histopathological changes and bone remodeling in the knee articular cartilage and subchondral bone in rats following treatment with glucocorticoids. A total of 30 3-month-old female Sprague-Dawley rats were randomly divided into either a vehicle control group or one of three experimental groups wherein dexamethasone (Dex) was administered at a dose of 1.0, 2.5 or 5.0 mg/kg (Dex1.0, Dex2.5 and Dex5.0, respectively), for 8 weeks. Articular cartilage and the epiphyseal subchondral bone of the proximal tibias were evaluated by histopathology or for bone remodeling using histomorphometry. No histological changes were identified in the knee articular cartilage but the bone formation rate of the subchondral bone was lower in the Dex1.0 group compared with that of the control group. Compared with the control and the Dex1.0 group, the width of the articular cartilage and the subchondral plate were larger, with abnormal morphology and increased apoptosis of chondrocytes, decreased cell/matrix volume ratio in the cartilage and fewer blood vessels in the subchondral plate in the Dex2.5 and Dex5.0 groups. A higher Dex dose resulted in more severe inhibition of bone formation, a greater number of apoptotic osteocytes and constrained bone resorption. All microstructure parameters indicated no significant changes in the Dex2.5 group but exhibited deterioration in the Dex5.0 group compared with the normal and Dex1.0 group. There were no significant differences in morphological changes, or in static and dynamic bone indices between the Dex2.5 and Dex5.0 groups. In conclusion, long-term glucocorticoid use induced dose-related histopathological changes in the knee articular cartilage, along with unbalanced bone remodeling and osteopenia in the subchondral bone. The degree of damage to the articular cartilage was milder and transformed from compensation to degeneration at higher doses.
本研究的目的是调查糖皮质激素治疗后大鼠膝关节软骨和软骨下骨的组织病理学变化及骨重塑情况。将30只3月龄雌性Sprague-Dawley大鼠随机分为溶剂对照组或三个实验组之一,其中分别以1.0、2.5或5.0 mg/kg的剂量给予地塞米松(分别为Dex1.0、Dex2.5和Dex5.0),持续8周。通过组织病理学评估胫骨近端的关节软骨和骨骺软骨下骨,或使用组织形态计量学评估骨重塑情况。膝关节软骨未发现组织学变化,但Dex1.0组软骨下骨的骨形成率低于对照组。与对照组和Dex1.0组相比,Dex2.5和Dex5.0组的关节软骨和软骨下板宽度更大,软骨细胞形态异常且凋亡增加,软骨中细胞/基质体积比降低,软骨下板血管减少。更高剂量的地塞米松导致对骨形成的抑制更严重,凋亡的骨细胞数量更多,骨吸收受限。所有微观结构参数表明,Dex2.5组与正常组和Dex1.0组相比无显著变化,但Dex5.0组出现恶化。Dex2.5组和Dex5.0组在形态学变化、静态和动态骨指标方面无显著差异。总之,长期使用糖皮质激素会导致膝关节软骨出现剂量相关的组织病理学变化,同时软骨下骨出现骨重塑失衡和骨质减少。关节软骨的损伤程度较轻,且在高剂量时从代偿转变为退变。