目标:在颅运动神经附近手术时,经常观察到目标肌肉持续数周至数月的短暂术后无力。由于手术完成时神经通常是完整的,假设麻痹是由神经失用症和轴突占位症的组合引起的。由于神经失用症和轴突分泌都涉及雪旺氏细胞损伤并需要髓鞘再生,我们使用过氧化氢(H2O2)诱导氧化应激,建立了体外RSC96雪旺氏细胞损伤模型,并研究了候选治疗剂促进RSC96活力的疗效.作为制定长期地方行政战略的第一步,这些药物中最有前途的药物被掺入到缓释微粒中,并使用该方法研究其生物活性.
方法:测定使活力降低50%的H2O2浓度以建立在RSC96培养物中诱导氧化应激的标准。然后将新鲜的培养物与H2O2和潜在的治疗剂褪黑激素共同给药,N-乙酰半胱氨酸,白藜芦醇,和4-氨基吡啶。施万细胞的活力进行了评估和最有效的试剂,N-乙酰半胱氨酸,被封装到微粒中。评价来自微粒的洗脱的N-乙酰半胱氨酸样品的保留的生物活性。
结果:100µMN-乙酰半胱氨酸改善了H2O2给药的施万细胞的活力。100μM微粒洗脱的N-乙酰半胱氨酸也增强了施万细胞的活力。
结论:我们开发了医源性神经损伤的雪旺氏细胞培养模型,并将其用于鉴定N-乙酰半胱氨酸作为促进恢复的药物。N-乙酰半胱氨酸被包装到微粒中,并被证明有希望作为一种可局部施用的试剂来减少雪旺氏细胞中的氧化应激。
OBJECTIVE: When operating near cranial motor nerves, transient postoperative weakness of target muscles lasting weeks to months is often observed. As nerves are typically intact at a procedure\'s completion, paresis is hypothesized to result from a combination of neurapraxia and axonotmesis. As both neurapraxia and axonotmesis involve Schwann cell injury and require remyelination, we developed an in vitro RSC96 Schwann cell model of injury using hydrogen peroxide (H2O2) to induce oxidative stress and investigated the efficacy of candidate therapeutic agents to promote RSC96 viability. As a first step in developing a long-term local administration strategy, the most promising of these agents was incorporated into sustained-release microparticles and investigated for bioactivity using this assay.
METHODS: The concentration of H2O2 which reduced viability by 50% was determined to establish a standard for inducing oxidative stress in RSC96 cultures. Fresh cultures were then co-dosed with H2O2 and the potential therapeutics melatonin, N-acetylcysteine, resveratrol, and 4-aminopyridine. Schwann cell viability was evaluated and the most efficacious agent, N-acetylcysteine, was encapsulated into microparticles. Eluted samples of N-acetylcysteine from microparticles was evaluated for retained bioactivity.
RESULTS: 100 µM N-acetylcysteine improved the viability of Schwann cells dosed with H2O2. 100 µM Microparticle-eluted N-acetylcysteine also enhanced Schwann cell viability.
CONCLUSIONS: We developed a Schwann cell culture model of iatrogenic nerve injury and used this to identify N-acetylcysteine as an agent to promote recovery. N-acetylcysteine was packaged into microparticles and demonstrated promise as a locally administrable agent to reduce oxidative stress in Schwann cells.