BACKGROUND Platelet-rich plasma (PRP) provides a nonsurgical approach for treating osteoarthritis (OA). Exosomes that play vital roles in intercellular communication have been studied extensively. Here, we investigated the therapeutic potential and molecular mechanism of exosomes derived from PRP (PRP-Exos) in alleviating OA. METHODS Exosomes derived from PRP(PRP-Exos) were isolated and purified using the exoEasy Maxi Kit and then identified and analyzed. Primary rabbit chondrocytes were isolated and treated with interleukin 1 beta (IL-1β) to establish the OA model in vitro. Proliferation, migration, and apoptosis assays were measured and compared between PRP-Exos and activated PRP (PRP-As) to evaluate the therapeutic effects on OA. The mechanism involving the Wnt/β-catenin signaling pathway was investigated by Western blot analysis. In vivo, we established animal knee OA model by surgery to compare the therapeutic effect of PRP-Exos and PRP-As. RESULTS We successfully isolated and purified exosomes from PRP using the exoEasy Maxi Kit. We also isolated and identified chondrocytes from the New Zealand white rabbit and established the IL-1β-induced OA model; meanwhile, PRP-Exos and PRP-As both inhibited the release of tumor necrosis factor-α(TNF-α) and there was no statistically significant difference between the two. In proliferation, migration, scratch assay, the promoting effect of PRP-Exos was significantly more better than PRP-As. Furthermore, PRP-Exos could significantly decreased apoptotic rate of OA chondrocyte compared with PRP-As. In Western blot analysis, the expression of β-catenin, and RUNX2, Wnt5a were increased in IL-1β-treated chondrocytes, but PRP-Exos and PRP-As could both reverse these changes, and the reversal effect of the former was better than the latter. In vivo, we found that both PRP-Exos and PRP-As displayed the progression of OA, and the effect of PRP-Exos was obviously better than PRP-As by chondrocyte count and Osteoarthritis Research Society International (OARSI) scoring system. CONCLUSION The therapeutic effects of PRP-Exos on OA were similar or better compared with those of PRP-As in vitro or in vivo. PRP-Exos acting as carriers containing growth factors derived from PRP present a novel therapy for OA by activating the Wnt/β-catenin signaling pathway.

中文翻译：

---

来源于富含血小板的血浆的外泌体具有通过Wnt /β-catenin信号通路促进增殖和抑制软骨细胞凋亡的缓解膝骨关节炎的新潜力。

背景技术富血小板血浆（PRP）提供了一种非手术方法来治疗骨关节炎（OA）。在细胞间通讯中起重要作用的外泌体已被广泛研究。在这里，我们研究了来自PRP（PRP-Exos）的囊泡减轻OA的治疗潜力和分子机制。方法使用exoEasy Maxi Kit分离和纯化源自PRP（PRP-Exos）的外泌体，然后进行鉴定和分析。分离兔原代软骨细胞并用白介素1β（IL-1β）处理以建立体外OA模型。测量了增殖，迁移和凋亡测定，并在PRP-Exos和活化PRP（PRP-As）之间进行了比较，以评估对OA的治疗效果。通过Western印迹分析研究了涉及Wnt /β-catenin信号传导途径的机制。体内，我们通过手术建立了动物膝关节OA模型，以比较PRP-Exos和PRP-As的治疗效果。结果我们使用exoEasy Maxi试剂盒成功地从PRP中分离和纯化了外泌体。我们还从新西兰白兔中分离并鉴定了软骨细胞，并建立了IL-1β诱导的OA模型。同时，PRP-Exos和PRP-As均抑制肿瘤坏死因子-α（TNF-α）的释放，两者之间无统计学意义。在增殖，迁移，划痕试验中，PRP-Exos的促进作用明显优于PRP-As。此外，与PRP-As相比，PRP-Exos可以显着降低OA软骨细胞的凋亡率。在Western印迹分析中，经IL-1β处理的软骨细胞中β-catenin和RUNX2，Wnt5a的表达增加，但是PRP-Exos和PRP-As都可以逆转这些变化，并且前者的逆转效果要好于后者。在体内，我们发现PRP-Exos和PRP-As均显示OA的进展，并且通过软骨细胞计数和国际骨关节炎研究协会（OARSI）评分系统，PRP-Exos的效果明显优于PRP-As。结论PRP-Exos对OA的体内或体外治疗效果与PRP-As相似或更好。充当包含源自PRP的生长因子的载体的PRP-Exos通过激活Wnt /β-catenin信号传导途径为OA提供了一种新的疗法。通过软骨细胞计数和国际骨关节炎研究学会（OARSI）评分系统，PRP-Exos的效果明显优于PRP-As。结论PRP-Exos对OA的体内或体外治疗效果与PRP-As相似或更好。充当包含源自PRP的生长因子的载体的PRP-Exos通过激活Wnt /β-catenin信号传导途径为OA提供了一种新型疗法。通过软骨细胞计数和国际骨关节炎研究学会（OARSI）评分系统，PRP-Exos的效果明显优于PRP-As。结论PRP-Exos对OA的体内或体外治疗效果与PRP-As相似或更好。充当包含源自PRP的生长因子的载体的PRP-Exos通过激活Wnt /β-catenin信号传导途径为OA提供了一种新的疗法。