The First Affiliated Hospital of Harbin Medical University, 23 You Zheng Street, Harbin, 150001, China.
J Orthop Surg Res. 2021 Oct 30;16(1):646. doi: 10.1186/s13018-021-02777-9.
Osteoarthritis is a chronic inflammatory disease of the joints associated with significant morbidity and lower quality of life. Current treatment strategies focus on reducing cartilage degeneration but fail to restore their proliferative ability. Super-activated platelet lysate (sPL) is an enhanced form of platelet-rich plasma that can be easily inactivated. The purpose of this study is to evaluate whether sPL-loaded PLGA/chitosan/gelatin microspheres can prevent and treat osteoarthritis.
Features of biological microspheres were detected by SEM and ELISA. Osteoarthritis chondrocytes were co-cultured with hydrogel loaded with sPL. The effect of biological microspheres on chondrocyte proliferation was evaluated using a CCK-8 cell proliferation test. Cell morphology and cell necrosis were measured with a microscope. The gene expression levels of cartilage-related markers type 2 collagen, aggrecan (ACAN), and SRY type high mobility group box-9 (SOX9) were determined by real-time quantitative polymerase chain reaction (Rt-PCR). A rat osteoarthritis model was established. Micro-CT was used to characterize cartilaginous changes after the injection of biological microspheres. Histopathological HE staining, Safranin-O Fast Green staining and staining scores, type II collagen staining, and proteoglycan staining were used to evaluate the degree of cartilaginous repair.
Biological microspheres were able to continuously release biological factors. Exposure to loading sPL microspheres significantly increased chondrocyte proliferation, reduced cell necrosis, and increased the expression of cartilage markers type 2 collagen, ACAN, and SOX9 in osteoarthritic chondrocytes. In vivo experiments found that biological microspheres also smoothen cartilage surfaces, promote the expression of proteoglycan and type 2 collagen while also increasing cartilaginous integrity as evaluated using Safranin-O Fast Green staining.
PLGA/chitosan/gelatin hydrogel loaded with sPL is a promising tool for effective and non-invasive articular cartilage repair in osteoarthritis. Biological microspheres loaded with sPL release various biological factors to promote chondrocyte proliferation and upregulate chondrocyte functionalization genes (SOX9, CoX II, ACAN), leading to an overall enhanced cartilaginous matrix.
骨关节炎是一种与显著发病率和较低生活质量相关的关节慢性炎症性疾病。目前的治疗策略侧重于减少软骨退化，但未能恢复其增殖能力。超激活血小板裂解液（sPL）是一种增强型富血小板血浆，可轻松失活。本研究旨在评估负载 sPL 的 PLGA/壳聚糖/明胶微球是否可预防和治疗骨关节炎。
通过 SEM 和 ELISA 检测生物微球的特征。将负载 sPL 的水凝胶与软骨细胞共培养。使用 CCK-8 细胞增殖试验评估生物微球对软骨细胞增殖的影响。通过显微镜测量细胞形态和细胞坏死。通过实时定量聚合酶链反应（Rt-PCR）测定软骨相关标志物 II 型胶原、聚集蛋白聚糖（ACAN）和性决定区 Y 框 9（SOX9）的基因表达水平。建立大鼠骨关节炎模型。通过微 CT 分析注射生物微球后软骨的变化。组织学 HE 染色、番红 O 快速绿染色和染色评分、II 型胶原染色和糖胺聚糖染色用于评估软骨修复程度。
生物微球能够持续释放生物因子。负载 sPL 微球的暴露显著增加了软骨细胞的增殖，减少了细胞坏死，并增加了骨关节炎软骨细胞中软骨标志物 II 型胶原、ACAN 和 SOX9 的表达。体内实验发现，生物微球还能使软骨表面光滑，促进糖胺聚糖和 II 型胶原的表达，同时通过番红 O 快速绿染色评估，还能增加软骨的完整性。
负载 sPL 的 PLGA/壳聚糖/明胶水凝胶是一种有前途的工具，可有效且非侵入性地修复骨关节炎中的关节软骨。负载 sPL 的生物微球释放各种生物因子，促进软骨细胞增殖，并上调软骨细胞功能化基因（SOX9、COX II、ACAN），从而整体增强软骨基质。
