Gamma radiation sterilization is the method used by the majority of tissue banks to reduce disease transmission from infected donors to recipients through bone allografts. However, many studies have reported that gamma radiation impairs the structural and mechanical properties of bone via formation of free radicals, the effect of which could be reduced using free radical scavengers. The aim of this study is to examine the radioprotective role of hydroxytyrosol (HT) and alpha lipoic acid (ALA) on the mechanical properties of gamma-sterilized cortical bone of bovine femur, using three-point bending and microhardness tests. Specimens of bovine femurs were soaked in ALA and HT for 3 and 7 days, respectively, before being exposed to 35-kGy gamma radiation. In unirradiated samples, both HT and ALA pre-treatment improved the cortical bone bending plastic properties (maximum bending stress, maximum bending strain, and toughness) without affecting microhardness. Irradiation resulted in a drastic reduction of the plastic properties and an increased microhardness. ALA treatment before irradiation alleviated the aforementioned reductions in maximum bending stress, maximum bending strain, and toughness. In addition, under ALA treatment, the microhardness was not increased after irradiation. For HT treatment, similar effects were found. In conclusion, the results indicate that HT and ALA can be used before irradiation to enhance the mechanical properties of gamma-sterilized bone allografts.

中文翻译：

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使用抗氧化剂增强伽马射线灭菌皮质骨的生物力学性能。

伽玛射线灭菌是大多数组织库用来减少疾病感染的供体通过同种异体骨移植到受体的方法。但是，许多研究报告称，γ射线会通过形成自由基而损害骨骼的结构和机械性能，使用自由基清除剂可以降低其影响。这项研究的目的是使用三点弯曲和显微硬度测试来检查羟基酪醇（HT）和α硫辛酸（ALA）对牛股骨γ灭菌皮质骨的力学性能的辐射防护作用。牛股骨标本分别在35kGyγ射线照射下分别在ALA和HT中浸泡3天和7天。在未经辐照的样品中 HT和ALA预处理均改善了皮质骨弯曲塑性性能（最大弯曲应力，最大弯曲应变和韧性），而不会影响显微硬度。辐照导致塑性性能大大​​降低，显微硬度增加。辐照前的ALA处理减轻了上述最大弯曲应力，最大弯曲应变和韧性的降低。另外，在ALA处理下，照射后的显微硬度没有增加。对于HT治疗，发现相似的效果。总之，结果表明可以在辐照前使用HT和ALA来增强经伽玛消毒的同种异体骨的机械性能。辐照导致塑性性能大大​​降低，显微硬度增加。辐照前的ALA处理减轻了上述最大弯曲应力，最大弯曲应变和韧性的降低。另外，在ALA处理下，照射后的显微硬度没有增加。对于HT治疗，发现相似的效果。总之，结果表明可以在辐照前使用HT和ALA来增强经伽玛消毒的同种异体骨的机械性能。辐照导致塑性性能大大​​降低，显微硬度增加。辐照前的ALA处理减轻了上述最大弯曲应力，最大弯曲应变和韧性的降低。另外，在ALA处理下，照射后的显微硬度没有增加。对于HT治疗，发现相似的效果。总之，结果表明可以在辐照前使用HT和ALA来增强经伽玛消毒的同种异体骨的机械性能。发现类似的效果。总之，结果表明可以在辐照前使用HT和ALA来增强经伽玛消毒的同种异体骨的机械性能。发现类似的效果。总之，结果表明可以在辐照前使用HT和ALA来增强经伽玛消毒的同种异体骨的机械性能。