糖皮质激素对股骨头微循环内皮细胞miRNAs表达谱的影响及大蒜素、淫羊藿苷的相应保护作用

Pathogenesis of femoral head necrosis is unclear. Blood circulation obstacle is the fundamental pathological changes; endothelial cell damage is an important factor to result in blood circulation obstacle. miRNAs were found to have an important regulatory role on endothelial cell function, and site-specific. The unique structure and function of bone microcirculation endothelial cells whether is regulated by site-specific miRNAs is unclear. miRNAs whether is an important affecting factor to participate steroid-induced damage of circulation endothelial cell in the femoral head necrosis is not reported. The application of miRNA microarray technology and forecasting software Pigtar is expected to determine the bone microcirculation endothelial cell-specific miRNAs and their function, to determine steroid-induced damage of the endothelial cell-related miRNAs and their function, to explore the mechanisms of steroid-induced damage of the endothelial cells and find the potential value of targeting drug prevention and treatment. Allicin is known as the drug of preventing and treating of cardiovascular disease. Icariin has also the role to protect vascular endothelial cells from steroid-induced damage. Their protective effect on bone circulating endothelial cells in steroid-induced damage whether is achieved by affecting the miRNAs is to be studied. To study the protective effect of allicin and icariin on steroid-induced damage of the endothelial cells and their relationship with miRNAs change, is expected from a new angle to explore the mechanism of allicin and icariin treating osteonecrosis and found the drug-targets of effective prevention and treatment of osteonecrosis, improve effective prevention and treatment methods of steroid-induced osteonecrosis.

激素性股骨头坏死发病机制不清，骨血液循环障碍是根本病理改变，而内皮细胞损害是其重要因素。miRNAs被发现对血管内皮细胞功能有重要调节作用，且有部位特异性。有独特结构与功能的骨微循环内皮细胞是否有独特的miRNAs调节作用不清楚。miRNAs是否是激素性股骨头坏死中循环内皮细胞损害的重要调节环节也无研究报告。通过应用miRNA芯片技术和Pigtar等预测软件，有望确定骨微循环内皮细胞特异性miRNAs及其功能，发现其激素性损伤相关miRNAs并确定功能，探讨内皮细胞激素性损伤机制，对寻找新的药物防治靶点有潜在应用价值。大蒜素有防治心血管病作用，淫羊藿苷有保护血管内皮细胞的作用，它们是否通过影响miRNAs而对骨循环内皮细胞的激素性损害有保护作用，有待研究。比较研究大蒜素和淫羊藿苷对内皮细胞损伤的保护效果和miRNAs改变的关联性，有望从全新角度探讨大蒜素和淫羊藿苷防治骨坏死的机制.

激素性股骨头坏死发生机制尚不完全清楚。大剂量糖皮质激素经miRNAs引起股骨头血管内皮细胞结构和功能的损害，导致骨组织的血供障碍。骨微循环内皮细胞有特异性miRNAs？miRNAs 是否有望成为药物治疗的靶点？ 该课题通过比较研究骨微循环内皮细胞与其它器官微循环内皮细胞miRNAs表达谱差异，确定骨微循环内皮细胞特异性miRNAs及其功能；通过体内体外研究，发现内皮细胞激素性损伤相关miRNA并确定其功能，探讨内皮细胞激素性损伤机制，并探讨将高度关联miRNA作为骨坏死诊断生化标记物的可能性；通过比较研究不同中药对内皮细胞损伤的保护效果和miRNA改变的关联性，探讨中药防治骨坏死的机制，并探讨将miRNAs作为临床潜在应用的骨坏死治疗药物作用靶点的可能性。通过体外实验研究表明，激素组BMECs凋亡率为(46．9％±5．8％)和(78．0％±8．5％)，较正常对照组(4.8％±1.3％)明显升高，淫羊藿苷+激素组细胞凋亡率(15.2％±7.7％)和(44.6％±5.3％)，较激素组明显降低(均P<0.001)。蛋白质芯片筛选结果发现激素组的粒细胞集落刺激因子(G-CSF)表达较正常对照组降低，同时炎性因子IL4表达升高；淫羊藿苷+激素组的G-CSF表达较激素组升高，同时炎性因子IL4表达降低，凋亡因子表达无明显变化。淫羊藿苷可以显著抑制糖皮质激素诱导的BMECs凋亡，提高促血管生成因子G-CSF的表达，抑制炎性因子IL-4表达，推测淫羊藿苷可能具有防治激素性股骨头坏死的作用。经体外实验研究对微小RNA 基因芯片结果进行差异性分析，与正常组相比较，激素组中差异倍数﹥2的微小RNA 共有5 个，其中1 个表达上调，4 个表达下调；②实时定量PCR 检测结果显示：与正常组相比，激素组中miR-339 及miR-23b 出现明显变化，与基因芯片结果一致。与激素组相比，淫羊藿苷预处理可以显著提高miR-23b 的表达；③结果表明：淫羊藿苷可以有效预防激素诱导骨微血管内皮细胞损伤引起的miR-23b 表达失衡，推测淫羊藿苷可能通过介导骨微血管内皮细胞miR-23b 的表达参与激素性股骨头坏死病理过程的调控淫羊藿苷可以有效预防激素诱导骨微血管内皮细胞损伤引起的miR-23b 表达失衡，推测淫羊藿苷可能通过介导骨微血管内皮细胞miR-23b 的表达参与激素性股骨头坏死病理过程。