目的 觀察梔子苷對腦缺血再灌注損傷（CIRI）模型大鼠的神經(jīng)保護作用及對胰高血糖素樣肽-1受體（GLP-1R）/蛋白激酶B（Akt）信號通路的影響。方法 50只SD大鼠隨機分為假手術(shù)組，模型組，梔子苷低、高劑量組及尼莫地平片組，每組10只。采用線栓法制備CIRI大鼠模型，缺血2 h再灌注24 h后，梔子苷低、高劑量組大鼠分別ig給予10、40 mg·kg^-1的梔子苷，尼莫地平片組大鼠ig給予8.1 mg·kg^-1尼莫地平，假手術(shù)組和模型組大鼠ig等體積生理鹽水，每天1次，連續(xù)7 d。造模后及給藥結(jié)束后，分別對各組大鼠進行神經(jīng)功能缺損評分；給藥結(jié)束后，采用酶聯(lián)免疫吸附法（ELISA）檢測血清中腫瘤壞死因子-α（TNF-α）、白細胞介素-1β（IL-1β）及白細胞介素-6（IL-6）水平，蘇木素-伊紅（HE）染色檢測腦組織病理學變化，尼氏染色檢測神經(jīng)元與尼氏小體變化，免疫組化染色檢測腦組織B淋巴細胞瘤-2（Bcl-2）和Bcl-2關(guān)聯(lián)X蛋白（Bax）表達，蛋白質(zhì)印跡法（Western blotting）檢測腦組織細胞色素C（Cyt-C）、半胱氨酸蛋白酶-3（Caspase-3）、半胱氨酸蛋白酶-9（Caspase-9）、胰高血糖素樣肽-1受體（GLP-1R）及磷酸化蛋白激酶B（p-Akt）蛋白表達水平。結(jié)果 與假手術(shù)組比較，模型組大鼠神經(jīng)功能缺損評分顯著升高（P＜0.05），血清中TNF-α、IL-1β、IL-6水平顯著升高（P＜0.05）；皮質(zhì)細胞間質(zhì)疏松、增寬，有大量神經(jīng)元細胞質(zhì)萎縮和細胞核損傷；腦神經(jīng)元皺縮，尼氏小體變小，數(shù)目明顯減少。大鼠腦組織Bcl-2表達顯著降低（P＜0.05），Bax表達顯著升高（P＜0.05）；腦組織中Cyt-C、Caspase-3、Caspase-9蛋白表達水平顯著升高（P＜0.05），GLP-1R和p-Akt蛋白表達水平顯著降低（P＜0.05）。與模型組比較，梔子苷高劑量組和尼莫地平片組大鼠神經(jīng)功能缺損評分均顯著降低（P＜0.05），血清中TNF-α、IL-1β、IL-6水平顯著降低（P＜0.05），皮質(zhì)細胞較為整齊，神經(jīng)元細胞和尼氏小體損傷減小，Bcl-2表達顯著升高（P＜0.05），Bax表達顯著降低（P＜0.05），同時，Cyt-C、Caspase-3及Caspase-9蛋白表達水平顯著下降（P＜0.05），GLP-1R和p-Akt蛋白表達水平顯著升高（P＜0.05）。結(jié)論 梔子苷能夠改善大鼠CIRI，減少神經(jīng)元凋亡，其作用機制可能與激活GLP-1R/Akt信號通路有關(guān)。

Objective To investigate effect of geniposide on cerebral ischemia-reperfusion injury (CIRI) and its effects on glucagon like peptide-1 receptor (GLP-1R)/protein kinase B (Akt) signaling pathway. Methods Fifty SD rats were randomly divided into sham operation group, model group, low-dose geniposide group, high-dose geniposide group, and nimodipine tablet group, with 10 rats in each group. The thread embolism method was used to establish the CIRI model. After 2 h of ischemia and 24 h of reperfusion, the rats in low-dose and high-dose geniposide groups were given 10 mg·kg^-1 and 40 mg·kg^-1 geniposide by ig, respectively, rats in the nimodipine tablet group were given 8.1 mg·kg-1 nimodipine ig, rats in the sham operation group and model group were given an equal volume of normal saline, once a day for seven consecutive days. After modeling and administration, the neurological deficits of rats in each group were scored. Enzyme linked immunosorbent assay (ELISA) was used to detect the content of tumor necrosis factor- α (TNF- α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in serum. Hematoxylin-eosin (HE) staining was used to detect brain histopathological changes. Nissl staining was used to detect changes in neurons and Nissl bodies. Immunohistochemical staining was used to detect the expression of B lymphocyte tumor-2 (Bcl-2) and Bcl-2 associated X protein (Bax) in brain tissue. Western blotting was used to detect cytochrome C (Cyt-C), Caspase-3, and Caspase-9, glucagon-like peptide-1 receptor (GLP-1R) and phosphorylated protein kinase B (p-Akt) protein expression levels. Results Compared with the sham operation group, the neurological deficit score of the model group was significantly higher (P < 0.05), the level of TNF-α, IL-1β, and IL-6 increased significantly (P < 0.05), cortical intercellular matrix was loose and widened, and there were a large number of neuronal cytoplasmic atrophy and nuclear damage, the brain neurons shrink, the Nissl body became smaller, and the number decreased significantly, the expression of Bcl-2 was significantly decreased (P < 0.05) and the expression of Bax was significantly increased (P < 0.05), the expression levels of Cyt-C, Caspase-3 and Caspase-9 protein in brain tissue were significantly increased (P < 0.05), and the expression levels of GLP-1R and p-Akt protein were significantly decreased (P < 0.05). After treatment, compared with model group, the neurobehavioral injury score of the high-dose geniposide group and nimodipine group was significantly reduced (P < 0.05), and the serum levels of TNF-α, IL-1β, and IL-6 were significantly reduced (P < 0.05), the cortical cells are relatively neat, the damage of neuronal cells and Nissl bodies were reduced, Bcl-2 expression was significantly increased, Bax expression was significantly reduced (P < 0.05). At the same time, the expression levels of Cyt-C, Caspase-3 and Caspase-9 protein decreased significantly, the expression levels of GLP-1R and p-Akt protein increased significantly (P < 0.05). Conclusion Geniposide can improve cerebral ischemia-reperfusion injury and reduce neuronal apoptosis in rats, and its mechanism may be related to the activation of GLP-1R/Akt signaling pathway.

R285.5

2021年廣東省醫(yī)學科研基金（B2022009）