全麻药经TRPA1-TRPV1途径加重局麻药所致糖尿病小鼠神经毒性损伤的机制研究

General anesthesia combined with local anesthesia is benefit for diabetic patients. However the peripheral nerve system is exposure under both general anesthetics (GA) and local anesthetics (LA). Whether the enhanced neurotoxicity by local anesthetics in diabetes will be affected by GA, is unknown. We found out that TRPV1 ion channel is responsible for LA induced neurotoxicity in diabetic mouse. Furthermore, propofol and isoflurane (GA) enhanced bupivacaine (LA)-induced neruotoxocity. It is known that TRPA1 can be activated by both propofol and isoflurane, and TRPA1 can modulate TRPV1 via modulator such as PKCε. We then found out that, the aggravating effect by propofol, but not isoflurane, could be restored by PKCε inhibitor in bupivacaine-induced diabetic injury. Hence we hypothesize that GA activates TRPA1, then modulates TRPV1 via modulator proteins, is responsible for aggravating LA-induced neurotoxicity in diabetes. To further determine the “GA-TRPA1-modulator-TRPV1-LA induced neurotoxictiy” modulation chain, we will establish wild-type and TRPA1 knock-out type 2 diabetic mouse model, as well as plasmids transfected cell model under hyperglymia culture environment, to figure out the molecular targets for clinical translational treatments via cellular, histology and animal studies.

区域神经阻滞复合全身麻醉为加快糖尿病（DM）患者术后康复的优化麻醉方式，但全麻药（GA）与局麻药（LA）将同时影响外周神经系统。DM增加LA所致神经毒性损伤，尚未确定GA对此有何影响。本课题组已证实布比卡因（LA）所致DM小鼠神经毒性为TRPV1依赖；并发现丙泊酚与异氟烷（常见GA）均加重布比卡因所致神经毒性损伤。已知丙泊酚与异氟烷可激活TRPA1；而TRPA1通过调节介质如PKCε恢复TRPV1活性。进一步预实验发现：PKCε抑制剂可缓解丙泊酚加重布比卡因所致细胞凋亡损伤，但对异氟烷的加重作用无效。据此我们推测：GA激活TRPA1，通过调节介质恢复TRPV1的活性，加重LA经TRPV1途径所致DM神经毒性损伤。本项目拟建立野生型与TRPA1敲除小鼠的2型DM模型，辅以质粒转染细胞的高糖培养模型，阐述“GA-TRPA1-调节介质-TRPV1-LA神经毒性”调控链，为临床转化提供作用靶点。

项目背景：局麻药介导的区域神经阻滞复合全身麻醉现已成为糖尿病（DM）患者术后快速康复的优化麻醉方式，但全麻药（GA）复合局麻药（LA）会对DM外周神经系统产生进一步影响。我们前期已经明确DM可增加LA所致神经毒性损伤，但尚未确定GA对此有何影响。.本研究主要内容：1. 明确了GA 加重 LA 所致糖尿病小鼠神经毒性与 TRPA1的关系；2. 阐明了GA 通过“TRPA1-调节介质-TRPV1”加重 LA 神经毒性损伤的特征。.重要结果及关键数据：本研究结果显示布比卡因（LA）所致DM小鼠神经毒性为TRPV1依赖；我们发现丙泊酚与异氟烷（常见GA）均加重布比卡因所致神经毒性损伤；丙泊酚与异氟烷可激活TRPA1；而TRPA1通过调节介质如PKCε恢复TRPV1活性。同时，PKCε抑制剂可缓解丙泊酚加重布比卡因所致细胞凋亡损伤，但对异氟烷的加重作用无效。.科学意义：本项目已建立II型DM小鼠模型和辅以质粒转染细胞的高糖培养模型。我们阐明了“GA-TRPA1-调节介质-TRPV1-LA神经毒性”调控链，为研究麻醉药对DM患者神经损伤的防治提供分子靶点。