目的 基于蛋白激酶 R 样内质网激酶（PERK）/真核起始因子 2α（eIF2α）/激活转录因子 4（ATF4）信号通 路探讨黄芪桂枝五物汤对 2 型糖尿病周围神经病变小鼠的作用及机制。方法 采用高脂饲料联合冰上活动刺激 骨骼肌胰岛素样生长因子 1 及胰岛素双受体功能缺失（MKR）小鼠，复制糖尿病周围神经病变（DPN）小鼠模型。 将 DPN 小鼠随机分为 4 组：模型组、黄芪桂枝五物汤低剂量组（6.25 g·kg-1 ·d-1 ）、黄芪桂枝五物汤高剂量组 （30 g·kg-1 ·d-1 ）、甲钴胺组（0.17 mg·kg-1 ·d-1 ），每组 8 只。另取 8 只同龄 FVB 小鼠作为正常组。按照上述剂量 灌胃给药（10 mL·kg-1 ），每日 1 次，连续 28 d。给药结束后测量各组小鼠体质量、空腹血糖值（FBG）；通过检 测小鼠足底热痛觉敏感性及坐骨神经传导速度评估周围神经功能情况；采用 HE、Masson 染色法观察坐骨神经 病理变化；透射电镜观察坐骨神经组织超微结构；TUNEL 染色法检测坐骨神经细胞凋亡率；Western Blot 法检 测坐骨神经组织内质网应激及凋亡相关蛋白表达水平。结果 与正常组比较，模型组小鼠体质量及 FBG 水平 均显著升高（P＜0.01）；舔（缩）足间隔时间显著缩短（P＜0.01），坐骨神经传导速度显著降低（P＜0.01）；坐骨 神经纤维排列混乱，形态不规则，部分轴索纤细萎缩，甚至消失，髓鞘肿胀，结构松散，部分呈空泡样改变， 有较多的蓝色胶原纤维沉积，胶原纤维阳性面积占比显著升高（P＜0.01）；坐骨神经髓鞘变形扭曲，施旺细胞 结构破坏，胞质水肿，髓鞘板层松散，可见虫蚀样改变，厚度不均匀，轴索皱缩；坐骨神经细胞凋亡率显著升 高（P＜0.01）；坐骨神经组织 PERK、eIF2α、ATF4、CHOP、Caspase-3、Bax 蛋白表达显著上调（P＜0.01）， Bcl-2 蛋白表达显著下调（P＜0.01）。与模型组比较，各给药组小鼠的 FBG 水平均显著降低（P＜0.05，P＜ 0.01）；舔（缩）足间隔时间显著延长（P＜0.05，P＜0.01），坐骨神经传导速度显著提高（P＜0.01）；坐骨神经纤 维排列较为有序，形态趋于规则，轴索结构较为完整，髓鞘形态较为清晰完整，脱髓鞘程度减轻，胶原纤维沉 积减少；坐骨神经髓鞘形态较规则；坐骨神经组织 eIF2α、ATF4、CHOP、Caspase-3（34 kDa）、Bax 蛋白表达 显著下调（P＜0.05，P＜0.01），Bcl-2 蛋白表达显著上调（P＜0.01）。与模型组比较，黄芪桂枝五物汤高剂量 组、甲钴胺组小鼠的体质量明显降低（P＜0.05）；坐骨神经胶原纤维阳性面积占比显著降低（P＜0.05，P＜ 0.01）；坐骨神经髓鞘板层结构较为致密，虫蚀样空洞减少，神经纤维层分离状态减轻；坐骨神经细胞凋亡率 明显降低（P＜0.05）；坐骨神经组织 PERK 蛋白表达显著下调（P＜0.05，P＜0.01）；坐骨神经组织 Caspase-3 （17 kDa）蛋白表达显著下调（P＜0.01）。结论 黄芪桂枝五物汤能够改善 DPN 小鼠的坐骨神经功能，减轻神经 组织病理损伤，可能与抑制 PERK/ eIF2α/ATF4 信号通路活性，下调促凋亡蛋白表达，上调抑凋亡蛋白表达， 降低坐骨神经细胞凋亡率有关。

Objective To investigate the effect and mechanism of Huangqi Guizhi Wuwu Decoction （HGWD） on type 2 diabetic peripheral neuropathy （DPN） in mice，focusing on the protein kinase R-like endoplasmic reticulum kinase （PERK）/eukaryotic initiation factor 2α（eIF2α）/activating transcription factor 4（ATF4） signaling pathway. Methods A DPN mouse model was established using high-fat diet feeding combined with ice activity stimulation in skeletal muscle insulin-like growth factor 1 and insulin double receptor function-deficient （MKR） mice. The DPN mice were randomly divided into four groups （n=8 per group）：model group，low-dose HGWD group （6.25 g·kg-1 ·d-1 ），highdose HGWD group （30 g·kg-1 ·d-1 ），and mecobalamin group （0.17 mg·kg-1 ·d-1 ）. An additional eight age-matched FVB mice served as the normal group. All treatments were administered intragastrically （10 mL · kg-1 ） once daily for 28 consecutive days. After treatment，body mass and fasting blood glucose （FBG） levels were measured. Peripheral nerve function was assessed by evaluating plantar thermal pain sensitivity and sciatic nerve conduction velocity. Pathological changes in the sciatic nerve were observed using HE and Masson staining. Ultrastructural alterations in the sciatic nerve were examined by transmission electron microscopy. Apoptosis rates in sciatic nerve tissues were detected via TUNEL staining. Protein expression levels of endoplasmic reticulum stress and apoptosis-related markers in the sciatic nerve were measured using Western Blot analysis. Results Compared with the normal group，the model group exhibited significantly increased body mass and FBG levels （P＜0.01）；significantly shortened paw withdrawal latency （P＜0.01） and reduced sciatic nerve conduction velocity （P＜0.01）； disorganized and irregularly arranged sciatic nerve fibers，partially atrophied and thinned axons，swollen and loosely structured myelin sheaths with vacuolar changes， increased deposition of blue collagen fibers，and a significantly elevated collagen fiber-positive area ratio （P＜0.01）； deformed and distorted myelin sheaths， disrupted Schwann cell structure， cytoplasmic edema， loosely arranged myelin lamellae with moth-eaten appearance，uneven thickness，and shrunken axons；significantly increased sciatic nerve cell apoptosis rate （P＜0.01）； and significantly upregulated protein expression of PERK， eIF2α， ATF4， CHOP， Caspase-3， and Bax （P＜0.01）， along with significantly downregulated Bcl-2 expression （P＜0.01）. Compared with the model group，all treatment groups showed significantly reduced FBG levels （P＜0.05，P＜0.01）； significantly prolonged paw withdrawal latency （P＜0.05， P＜0.01） and improved sciatic nerve conduction velocity （P＜0.01）； relatively ordered sciatic nerve fiber arrangement， more regular morphology， relatively intact axonal structure，clearer and more complete myelin sheath morphology，reduced demyelination，and decreased collagen fiber deposition； relatively regular myelin sheath morphology； significantly downregulated protein expression of eIF2α， ATF4，CHOP，Caspase-3（34 kDa），and Bax （P＜0.05，P＜0.01），and significantly upregulated Bcl-2 expression （P＜0.01）. Compared with the model group， the high-dose HGWD and mecobalamin groups exhibited significantly reduced body mass （P＜0.05）；significantly decreased collagen fiber-positive area ratio in the sciatic nerve （P＜0.05， P＜0.01）；denser myelin lamellar structure，reduced moth-eaten vacuoles，and alleviated separation of nerve fiber layers；significantly reduced sciatic nerve cell apoptosis rate （P＜0.05）；significantly downregulated PERK protein expression （P＜0.05，P＜0.01）；and significantly downregulated Caspase-3（17 kDa） protein expression （P＜0.01）. Conclusion HGWD can improve sciatic nerve function and alleviate pathological damage in DPN mice，potentially by inhibiting the PERK/eIF2α/ATF4 signaling pathway， downregulating pro-apoptotic protein expression， upregulating anti-apoptotic protein expression，and reducing sciatic nerve cell apoptosis.

R285.5

国家自然科学基金项目（82074400，U21A20411）；中药粉体与创新药物省部共建国家重点实验室培育基地开放基金项目 （2022FTKFJJ06）；湖南省中医药管理局项目（B2023008）；湖南省教育厅优秀青年项目（22B0389）；2021 年度湖南省大学生创新创业训练计划 项目（S202110541033）。