目的 研究间充质干细胞注射液（MSCsI）对手术法诱导的大鼠膝骨关节炎的治疗作用。方法 自70只大鼠中随机取8只为假手术组，其余62只动物均进行右侧膝关节单侧手术造模。术后4周，进行X光检查并进行K-L评分，选择模型成功、状态良好的模型动物40只，根据K-L评分随机分为模型组、玻璃酸钠（阳性药，每关节腔0.5 mg玻璃酸钠注射液）组和MSCsI低、中、高剂量（每关节腔1.5×10⁵、5.0×10⁵、1.5×10⁶个细胞）组，每组8只。分组后次日开始，玻璃酸钠组每周1次，其余各组每2周1次，关节腔内注射给药，持续5周，假手术组与模型组给予等体积0.9%氯化钠溶液。使用X射线机检测大鼠膝关节病变；给药后记录大鼠行为学及痛阈变化；剖杀时记录关节软骨大体评分；试剂盒法检测血清中白细胞介素-1β（IL-1β）、白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、转化生长因子β（TGF-β）、II型胶原C端肽（CTX-Ⅱ）、前列腺素E₂（PGE₂）水平；取膝关节组织进行病理切片，HE染色、甲苯胺蓝染色观察组织损伤。结果 与模型组相比，MSCsI高剂量显著降低大鼠X光评分（P<0.05）、降低大鼠关节软骨大体观察评分（P<0.05）；给药4周后，MSCsI低、中、高剂量显著降低大鼠行为学评分（P<0.05、0.01），中、高剂量显著升高大鼠痛阈值（P<0.01）；MSCsI低剂量显著降低血清中IL-1β水平、升高TGF-β水平（P<0.05），中剂量显著降低血清中IL-1β、IL-6、CTX-Ⅱ水平、升高TGF-β水平（P<0.05、0.01），高剂量显著降低血清中IL-1β、IL-6、CTX-Ⅱ、PGE₂水平、升高TGF-β水平（P<0.05、0.01）；HE染色结果显示，MSCsI各剂量能有效减轻模型大鼠组织病理学改变，滑膜、软骨及软骨下骨病变较轻；甲苯胺蓝染色显示，MSCsI各剂量可减小模型大鼠软骨基质损伤。结论 MSCsI每2周1次关节腔内注射对手术诱导的大鼠膝骨关节炎有明显的治疗作用。

Objective To evaluate the efficacy of Mesenchymal Stem Cells Injection (MSCsI) on knee osteoarthritis induced by surgery in rats. Methods Eight out of 70 rats were randomly selected as the sham-operated group, while the remaining 62 animals underwent unilateral surgical modeling of the right knee joint. Four weeks after surgery, X-ray examination and K-L score were performed. Forty model animals with successful and good condition were selected and randomly divided into model group, sodium hyaluronate (positive drug, 0.5 mg sodium hyaluronate injection per joint cavity) group, and MSCsI low, medium, and high doses (1.5×10⁵, 5.0×10⁵, 1.5×10⁶ per joint cavity) group based on K-L score, with eight in each group. Starting from the day after grouping, the sodium hyaluronate group was given once a week, while the other groups were given intra-articular injection once every two weeks for five weeks. The sham-operated group and model group were given an equal volume of 0.9% sodium chloride solution. The knee lesions of rats were detected by X-ray machine. The behavior and pain threshold of rats were recorded after administration. The gross observation score of articular cartilage was recorded during dissection. Serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), C-terminal peptide of type II collagen (CTX-Ⅱ) and prostaglandin E₂ (PGE₂) were detected by kits. The knee tissue was taken for pathological section, and the tissue injury was observed by HE staining and toluidine blue staining. Results Compared to model group, MSCsI 1.5×10⁶ cells significantly reduced the X-ray score of rats (P< 0.05) and the gross observation score of rat articular cartilage (P< 0.05). After four weeks of administration, MSCsI 1.5×10⁵, 5.0×10⁵, and 1.5×10⁶ cells significantly reduced rat behavioral scores (P< 0.05, 0.01), 5.0×10⁵, 1.5×10⁶ cells significantly increased the pain threshold in rats (P< 0.01). MSCsI 1.5×10⁵ cells significantly reduce IL-1β in serum level, elevated TGF-β level (P< 0.05), 5.0×10⁵ cells significantly reduce IL-1β, IL-6, CTX-Ⅱ levels in serum, elevated TGF-β level (P< 0.05, 0.01), 1.5×10⁶ cells significantly reduce IL-1β, IL-6, CTX-Ⅱ, PGE2 levels in serum, elevated TGF-β levels (P< 0.05, 0.01). The HE staining results showed that each dose of MSCsI could effectively alleviate the histopathological changes in the model rats, with mild synovial, cartilage, and subchondral bone lesions. Toluidine blue staining showed that various doses of MSCsI can reduce cartilage matrix damage in model rats. Conclusion Intra-articular injection of stem cells once every two weeks has a significant therapeutic effect on surgically induced knee osteoarthritis in rats.

R965