Estrogen, a steroid hormone, plays an important role in modulating osteoclast proliferation and development. Estrogen deficiency boosts osteoclast activity, leading to osteoporosis in elderly women. In this study, 17-ß estradiol (E2)-loaded poly(ε-caprolactone) (PCL)/silk fibroin (SF) electrospun microfibers were developed as a proposed localized E2 delivery system to treat osteoporotic fractures. PCL is a synthetic polymer known for its biocompatibility and excellent mechanical properties. The bioactivity of PCL was enhanced by mixing it with a natural SF polymer that has low immunogenicity and inherent bioactivity. Different ratios of PCL/SF blends were electrospun and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle measurement. PCL and SF at a ratio of 50:50 (PCL50/SF50) augmented cell proliferation of murine preosteoblast MC3T3-E1 cells and murine preosteoclast RAW 264.7 cells. Hence, PCL50/SF50 was selected and mixed with three concentrations of E2 to produce electrospun fiber mesh (0.1% [email protected]/SF, 1% [email protected]/SF, and 5% [email protected]/SF). Sustained release of E2 was obtained for about 3 weeks at higher E2 concentration 5% [email protected]/SF. An E2-loaded PCL50/SF50 elecrospun microfiber (1% [email protected]/SF and 5% [email protected]/SF) reduced tartrate-resistant acid phosphate activity, total DNA, and multinucleated cell formation of osteoclasts. On the other hand, the alkaline phosphatase activity and collagen I expression of osteoblasts were retained on all E2-loaded electrospun microfibers. The [email protected]/SF system shows potential to be used for localized E2 delivery for the treatment of osteoporotic fractures.

中文翻译：

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负载雌二醇的聚（ε-己内酯）/丝素蛋白电纺微纤维降低破骨细胞活性并保持成骨细胞功能

雌激素是一种类固醇激素，在调节破骨细胞的增殖和发育中起重要作用。雌激素缺乏会增强破骨细胞活性，导致老年妇女骨质疏松。在这项研究中，开发了负载17-ß雌二醇（E2）的聚（ε-己内酯）（PCL）/丝素蛋白（SF）电纺微纤维，作为拟议的局部E2递送系统来治疗骨质疏松性骨折。PCL是一种合成聚合物，以其生物相容性和出色的机械性能而著称。通过将PCL与具有低免疫原性和固有生物活性的天然SF聚合物混合，可以增强PCL的生物活性。静电纺丝不同比例的PCL / SF混合物，并通过扫描电子显微镜，傅里叶变换红外光谱和水接触角测量进行表征。PCL和SF的比例为50：50（PCL50 / SF50）增强了小鼠前成骨细胞MC3T3-E1细胞和小鼠前破骨细胞RAW 264.7细胞的细胞增殖。因此，选择PCL50 / SF50并与三种浓度的E2混合以生产电纺纤维网（0.1％[受电子邮件保护] / SF，1％[受电子邮件保护] / SF和5％[受电子邮件保护] / SF）。在较高的E2浓度5％（受电子邮件保护）/ SF的情况下，E2的释放持续约3周。装有E2的PCL50 / SF50静电纺丝超细纤维（1％[受电子邮件保护] / SF和5％[受电子邮件保护] / SF）降低了抗酒石酸的酸性磷酸酶活性，总DNA以及破骨细胞的多核细胞形成。另一方面，成骨细胞的碱性磷酸酶活性和胶原蛋白I表达在所有负载E2的电纺微纤维上均保留。