ROS/TRPM2/Calpain介导自噬流受阻在布比卡因加重db/db小鼠神经损伤中的作用机制

糖尿病为我国严重公共卫生问题，此类患者实施神经阻滞与镇痛治疗时，局麻药神经毒性损伤增强，加重神经损伤与功能障碍。我们研究已证实高血糖增强局麻药致神经细胞活性氧簇（ROS）爆发与该现象密切相关。ROS可调控自噬，上述现象中神经损伤加重为过度自噬还是自噬流受阻所致？我们发现布比卡因致高糖孵育神经细胞与db/db小鼠（Lepr-/-糖尿病小鼠）脊髓神经损伤时，自噬流受阻与之相关；ROS/M型瞬时受体电位通道2（TRPM2）/钙蛋白酶（Calpain）参与调控上述模型中自噬流受阻。设想：高血糖增强布比卡因致神经细胞ROS爆发，调控TRPM2/Calpain通路损伤溶酶体功能，介导自噬流受阻，加重其神经毒性损伤。本研究拟构建高糖孵育SH-SY5Y细胞株与db/db小鼠脊髓神经布比卡因损伤模型，应用病毒感染、膜片钳与钙成像等技术证实上述设想，为糖尿病敏化局麻药神经毒性损伤的机制研究与防治提供新思路。

Diabetes has been a serious public health problem in China. When nerve blocking anesthesia and analgesia are performed, diabetes can enhance the local anesthetic-induced neurotoxicity and result in neurological dysfunction. Our previous studies have confirmed that hyperglycemia enhances local anesthetic-induced reactive oxygen species (ROS) overproduction which is closely related to this phenomenon. However its regulatory mechanism is unclear. We found that autophagy flux blockade was related to bupivacaine-induced neurotoxicity in nerve cells incubation with high glucose and spinal cord of db/db diabetic mice. ROS/M type transient receptor potential channel 2 (TRPM2)/calpain signaling was involved in regulating autophagy flux blockade in these models. It was suggested that hyperglycemia could enhance bupivacaine-induced ROS overproduction, block autophagy flux via activation of TRPM2/calpain signaling, and aggravate bupivacaine-induced neurotoxicity. The purpose of this study is to establish models of bupivacaine-induced neurotoxicity in SH-SY5Y cells incubation with high glucose and spinal cord of db/db diabetic mice. Virus infection, patch-clamp and calcium imaging techniques will be used to elucidate the role of autophagy flux blockade in hyperglycemia-mediated enhancement of bupivacaine-induced neurotoxicity and its mechanism of autophagy flux blockade mediated by ROS/TRPM2/calpain signaling. This study could provide a new idea for the prevention and treatment of nerve injury aggravation after the application of local anesthetic in diabetic patients.