GLP-1对2型糖尿病大鼠肝脏脂肪变性及JNK通路影响的研究

发布时间：2018-05-05 10:31

本文选题：2型糖尿病 + 大鼠　；参考：《昆明医科大学》2017年硕士论文

【摘要】：目的:探讨GLP-1类似物(利拉鲁肽)对2型糖尿病大鼠肝脏脂肪变性及JNK通路的影响。方法:SPF级健康雄性SD大鼠90只,随机分为正常对照组(NC组)20只和实验组70只。实验组采用高脂高糖饮食联合腹腔注射小剂量链脲佐菌素诱导建立2型糖尿病大鼠模型。成模大鼠随机化分为3组:利拉鲁肽低剂量(400μg/kg)干预组(LR-L)18只,利拉鲁肽高剂量(800μg/kg)干预组(LR-H)18只,糖尿病对照组(DM)19只。干预组按其剂量每日皮下注射利拉鲁肽1次,DM组和NC组以等量生理盐水皮下注射,共4周。每周监测各组大鼠的血糖、体重并记录,同时观察其饮食情况以及精神状态。干预4周后,所有大鼠3%戊巴比妥钠腹腔注射麻醉,收集大鼠血清,检测大鼠血糖、血脂、肝功能、胰岛素抵抗相关指标。留取肝组织,酶联免疫法测定肝组织TNF-α;HE染色观察2型糖尿病大鼠肝脏病理学改变,免疫组化法检测JNK1及P-JNK1的表达;荧光定量PCR测定JNK1mRNA在肝脏中的表达。结果:利拉鲁肽干预治疗4周末:①体重:NC组DM组LR-H、LR-L组(分别为:337.77±28.64、250.29±19.02、220.25±22.49、206.73±26.50,P0.05);②血糖及血脂:FBG:DM 组LR-H、LR-L 组NC 组(分别为:24.14±4.11、18.99±3.65、19.35±3.94、5.51±1.18,P0.05);TG:DM组LR-H、LR-L 组、NC 组(分别为:0.64±0.10、0.51±0.17、0.51±0.13、0.24±0.08,P0.05);TC:DM组LR-H、LR-L组NC 组(分别为:1.74±0.88、1.23±0.13、1.16±0.21、0.85±0.22,P0.05);③HOMA-IR 及 ISI:干预前 HOMA-IR:DM、LR-H、LR-LNC 组(分别为:33.37±8.74、32.58±5.42、32.09±5.20、5.82±1.13,P0.05);干预前 ISI:NC 组DM、LR-H、LR-L 组(分别为:-4.85±0.20、-6.59±0.26、-6.58±0.17、-6.57±0.17,P0.05);干预4周后HOMA-IR均明显较前下降,ISI有所升高(P0.05),干预后HOMA-IR:DM 组LR-H、LR-L 组NC 组(分别为:33.79±6.74、26.46±4.01、26.32±5.27、6.16±1.87,P0.05);干预后 ISI:NC 组LR-H、LR-L 组DM 组(分别为:-4.88±0.33、-6.61±0.21、-6.34±0.17、-6.37±0.19,P0.05)④ALT:DM 组NC 组、LR-H 组LR-L 组(分别为:153.33±51.32、103.80±40.17、109.44±36.24、144.75±45.91,P0.05);⑤肝组织切片HE染色及NAS积分:光镜下观察NC组大鼠肝细胞排列整齐,肝小叶规则,细胞中央有大而圆的核,细胞质均匀,无脂肪变性及炎症细胞浸润。DM组肝细胞排列不规则,伴有肝细胞肿胀、脂肪变性,存在炎细胞浸润,部分出现点、灶状坏死。LR-H组及LR-L组肝细胞病理改变明显减轻:NAS积分:DM组LR-H、LR-R 组NC 组(分别为:4.29±0.95、2.13±0.99、2.18±1.25、0.92±0.64,P0.05);⑥TNF-α及 JNK1mRNA:DM 组LR-H、LR-L 组NC 组(TNF-α分别为:1490.40±75.11、1282.09±133.31、1261.58±178.20、1108.11±110.41;JNK1mRNA分别为:2.02±0.23、1.41±0.26、1.41±0.27、1.01±0.16,P0.05);⑦JNK1 蛋白及P-JNKI蛋白组内及各组间差异均无统计学意义(P0.05);结论:①高脂高糖喂养SD大鼠5周后腹腔注射STZ35mg/kg,可诱导具有高血糖、高血脂、高胰岛素血症和胰岛素抵抗特征的2型糖尿病非酒精性脂肪肝病(NAFLD)模型。②利拉鲁肽可降低2型糖尿病大鼠体重、空腹血糖,改善胰岛素抵抗,增加胰岛素敏感性,降低肝指数、血清TC、TG水平。③利拉鲁肽干预可改善2型糖尿病NAFLD肝脏脂肪变性及NAS积分。④利拉鲁肽可降低TNF-α水平,下调JNK1 mRNA表达。⑤利拉鲁肽改善2型糖尿病肝脏脂肪变性的作用可能是通过降低肝细胞炎症因子TNF-α水平,从而抑制JNK信号通路的活性来实现的。
[Abstract]:Objective: To investigate the effect of GLP-1 analogues (lyacinin) on hepatic steatosis and JNK pathway in type 2 diabetic rats. Methods: 90 SPF healthy male SD rats were randomly divided into normal control group (NC group) 20 and experimental group 70. The experimental group was induced by high fat and high glucose diet combined with small dose streptozotocin to induce type 2 diabetes mellitus. Rat model rats were divided into 3 groups: 3 groups of Liraru peptide low dose (400 g/kg) intervention group (LR-L), high dose of Liraru peptide (800 mu g/kg) intervention group (LR-H) 18 and 19 diabetic control group (DM). The intervention group was subcutaneous injection of Liraru peptide every day at its dose, and group DM and NC group were subcutaneously injected with normal saline for 4 weeks. The blood sugar, weight and record of rats were measured and the diet and mental state were observed at the same time. After 4 weeks, 3% pentobarbital sodium was injected into the rat serum to detect the blood glucose, blood lipid, liver function and insulin resistance related indexes. The liver tissue was retained and the liver tissue TNF- alpha was determined by ELISA; HE staining observation was used to observe the liver tissue. Liver pathological changes in type 2 diabetic rats, immunohistochemical method to detect the expression of JNK1 and P-JNK1; fluorescence quantitative PCR to determine the expression of JNK1mRNA in the liver. Results: lial Lu peptide intervention therapy for 4 weekend: (1) weight: LR-H in group DM group NC, LR-L group (337.77 + 28.64250.29 + 19.02220.25 + 22.49206.73 + 26.50, P0.05); 2. Group FBG:DM LR-H, group LR-L, group NC (24.14 + 4.11,18.99 + 3.65,19.35 + 1.18, P0.05), TG:DM group LR-H, LR-L group, NC group (respectively 0.64 + 1.74 + + 0.22, 0.22, respectively); Pre HOMA-IR:DM, LR-H, and LR-LNC group (33.37 + 8.74,32.58 + 5.42,32.09 + 5.20,5.82 + 1.13, P0.05), before intervention, DM, LR-H, LR-L group (respectively: -4.85 + 0.20, + 0.26, 0.17, 0.17, respectively). Group C (33.79 + 6.74,26.46 + 4.01,26.32 + 5.27,6.16 + 1.87, P0.05), LR-H in group ISI:NC and DM group in group LR-L (respectively: -4.88 + 0.33, -6.61 + 0.21, -6.34 0.17, 0.19 and 45.91, respectively); liver tissue cut HE staining and NAS integral: observed under light microscope, the liver cells in group NC were arranged orderly, liver lobule rule, large and round nucleus in the central cell, homogeneous cytoplasm, fat free degeneration and inflammatory cell infiltration in group.DM, group of hepatocytes were irregular, accompanied by hepatocyte swelling, fatty degeneration, inflammatory cell infiltration, partial appearance, focal necrosis,.LR-H and L The pathological changes of hepatocytes in group R-L were obviously reduced: NAS integral: group DM LR-H, group NC of LR-R group (4.29 + 0.95,2.13 + 0.99,2.18 + 1.25,0.92 + 0.64, P0.05); 6. TNF- alpha and JNK1mRNA:DM group (1490.40 + + 2.02 + 0 respectively); 2.02 + 0 0 respectively .26,1.41 + 0.27,1.01 + 0.16, P0.05), and there was no significant difference between the groups of JNK1 protein and P-JNKI protein group and each group (P0.05). Conclusion: (1) high fat and high glucose feeding of SD rats after 5 weeks of intraperitoneal injection of STZ35mg/kg can induce non alcoholic fatty liver disease of type 2 diabetes with the characteristics of hyperglycemia, hyperlipidemia, hyperinsulinemia and insulin resistance. NAFLD) model. (2) lialuru can reduce the weight of type 2 diabetic rats, fasting blood glucose, improving insulin resistance, increasing insulin sensitivity, reducing liver index, serum TC, TG level. (3) lialurin intervention can improve the NAFLD liver fatty degeneration and NAS score in type 2 diabetes mellitus. (4) lialuru can reduce the level of TNF- alpha and reduce the expression of JNK1 mRNA. The effect of lialurin on hepatic steatosis in type 2 diabetes may be achieved by reducing the level of inflammatory factor TNF- alpha in liver cells and inhibiting the activity of JNK signaling pathway.

【学位授予单位】：昆明医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R587.2;R575

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