胰高血糖素样肽-1类似物对人成骨细胞Wnt信号通路相关基因表达的影响

目的 观察胰高血糖素样肽-1类似物（利拉鲁肽）对人成骨细胞增殖及Wnt信号通路相关因子mRNA的表达,探讨胰高血糖素样肽-1(GLP-1)与骨代谢的关系。方法 向体外培养的人成骨细胞中分别加入浓度为0mol/L、10-7mol/L、10-8mol/L、10-9mol/L的GLP-1类似物,24h后采用Cell Counting Kit-8(CCK-8)比色法检测成骨细胞增殖率,实时荧光定量PCR（Real-time RT-PCR）法检测Wnt-3a、LRP-5、β-catenin mRNA 的表达。结果 （1）GLP-1促进人成骨细胞增殖（P<0.05）,随着给药浓度的增高,成骨细胞增殖率下降（P<0.05）;（2）低浓度GLP-1（10-9mol/L）上调人成骨细胞中Wnt-3a、LRP-5、β-catenin mRNA 的表达(P<0.05);高浓度GLP-1（10-7mol/L、10-8mol/L）下调人成骨细胞中Wnt-3a、LRP-5、β-catenin mRNA 的表达(P<0.05)。结论 GLP-1促进人成骨细胞的增殖,低浓度时Wnt信号通路可能参与了该调控过程,高浓度抑制Wnt信号通路相关基因的表达。     

胰高血糖素样肽-2对烧伤大鼠肠粘膜细胞增殖的影响

目的　探讨胰高血糖素样肽 2 (GLP 2 )对烧伤大鼠肠粘膜细胞增殖及肠粘膜结构的影响。　方法　 5 5只Wistar大鼠随机分为烧伤组、GLP 2组 (烧伤后经GLP 2处理 ,2 0 0 μg/kg ,2次 /d腹腔注射 )与正常对照组。前两组动物于 30 %TBSAⅢ度烧伤后 6、12h及 1、3、5d分别处死 ,另处死正常对照组大鼠。检测各组增殖细胞核抗原 (PCNA)、细胞周期蛋白CyclinD的表达情况以及血浆二胺氧化酶 (DAO)的活性 ,并行肠粘膜组织学观察。　结果　与正常对照组比较 ,烧伤组伤后 6、12hPCNA表达稍有增强 ,伤后 1d减弱 ,3d时最低 ,5d时仍低于正常 ;GLP 2组PCNA表达的变化在伤后早期与烧伤组基本一致 ,但伤后 3、5d时强于烧伤组。烧伤组大鼠肠粘膜CyclinD蛋白在伤后 6、12h略有升高 ,但 1d时迅速下降至伤前的 4 0 % ,而GLP 2组CyclinD蛋白表达在伤后 1、3、5d高于烧伤组。大鼠烧伤后血浆DAO活性明显升高 ,经GLP 2治疗 5d后该指标明显降低 (P <0 .0 1)。组织学观察见GLP 2组肠绒毛排列较为规则 ,长短较一致 ,未见明显的上皮脱落。　结论　大鼠烧伤后腹腔给予外源性GLP 2能减轻肠粘膜损伤 ,其机制可能与GLP 2使PCNA、ClyclinD表达增加、促进受损肠粘膜细胞增殖有关。     

胰高血糖素样肽-2临床应用研究进展

<正>胰高血糖素样肽-2(glucagon-like peptide-2,GLP-2)是新近发现的肠上皮特异性生长因子,是胰腺α细胞、肠L细胞和中枢神经元的胰高血糖素原基因转录、翻译后处理加工的33氨基酸的多肽,     

胰高血糖素样肽-1在骨质疏松症中的影响及作用机制的研究进展

胰高血糖素样肽-1受体激动剂(glucagon like peptide-1 receptor agonists, GLP-1RAs)作为一种抗糖尿病药物,近年来对骨质疏松症的影响越来越受到人们的关注。而胰高血糖素样肽-1(glucagon like peptide-1, GLP-1)在骨质疏松症患者中的具体作用及相关机制有待进一步探讨和阐明。本文回顾及总结了近年来的文献,综述了GLP-1在治疗骨质疏松症中的研究进展,希望可以为治疗骨质疏松提供新思路。     

胰高血糖素样肽-1及其类似物保护认知功能的研究进展

背景 认知功能障碍是指学习记忆、思维判断等大脑高级功能异常,目前尚无确切的防治药物.2型糖尿病被公认为发生认知功能障碍的危险因素.胰高血糖素样肽-1（glucagon-like peptide-1,GLP-1）及其类似物是一种针对2型糖尿病的新型降糖药,研究发现其还具有保护认知功能的作用. 目的 为GLP-1及其类似物应用于临床防治认知功能障碍提供理论依据. 内容 就GLP-1及其类似物的保护认知功能的研究现状作一综述. 趋向 有望成为防治认知功能障碍等神经病理性疾病的新型药物.     

胰高血糖素样肽1及其受体在代谢外科手术治疗机制中的作用

目前外科手术已经成为治疗2型糖尿病治疗方式之一,但对于其治疗机制仍然还不明确.很多试验证明,糖尿病外科手术以后,解剖生理结构的改变导致了与代谢有关胃肠道分泌的激素和神经肽类分子水平的明显变化,这些分子在功能上与葡萄糖代谢、胰岛细胞功能、胰岛素敏感性相关,其中研究较为深入的是胰高血糖素样肽 -1（gucagon-like peptide-1 GLP-1）,其在外科手术治疗糖尿病中所起的重要作用已得到人们越来越多的认可.而GLP-1必须与GLP-1受体（GLP-1 receptor GLP-1R）结合后才能发挥其生理作用.本文就GLP-1及其受体在代谢外科手术治疗机制中的作用作一综述.     

胰高血糖素样肽1受体激动剂的肾脏保护作用

糖尿病肾病(DKD)是糖尿病最常见的微血管并发症之一,其发病机制复杂,治疗手段有限,寻找新的方法防治DKD已成为当今研究的重要方向。有研究发现,胰高血糖素样肽1受体激动剂(GLP-1RAs)具有不依赖于血糖的肾脏保护作用,可预防蛋白尿的发生,可能有助于延缓2型糖尿病患者估算肾小球滤过率(eGFR)的下降。本文就GLP-1RAs的肾脏保护机制及临床证据进行综述。     

胃转流术对2型糖尿病大鼠的血糖及胰高血糖素样肽-1的影响

目的 观察胃转流术(GBP)对糖尿病大鼠血糖的控制效果及胰高血糖素样肽-1(GLP-1)的影响.方法 采用链脲佐菌素建立糖尿病SD大鼠模型20只,随机分为糖尿病手术组(DO组)和糖尿病对照组(DC组),另取20只非糖尿病大鼠随机分为正常对照组(NC组)和正常手术组(NO组).分别检测各组大鼠术前、术后72 h、1周、4周和8周空腹血糖水平以及血清GLP-1浓度.结果 术前DO组与DC组以及NC组与NO组大鼠空腹血糖之间的比较差异均无统计学意义(P＞0.05);DO组大鼠术后空腹血糖进行性下降,术后8周由术前的(20.84±1.98) mmol/L下降到(5.56±0.11) mmol/L(P＜0.05);DC组大鼠术前及术后各时相的差异无统计学意义(P＞0.05).DO组和NO组大鼠术后血清GLP-1浓度出现明显升高(P＜0.05),术后8周分别由术前的(7.10±0.55)、(10.73 ±0.67) pmol/L上升到(26.48±1.14)、(13.98±0.92) pmol/L(P＜0.05).结论 GBP对2型糖尿病大鼠具有明显的降糖作用,GLP-1的升高在其中起着重要作用,但对正常大鼠血糖无影响.     

胃肠道营养物质代谢与胰高血糖素样肽-1水平改变

目的介绍胃肠道营养物质代谢与胰高血糖素样态-1(GLP-1)水平关系的研究现状。方法收集近年来国内、外有关胃肠道营养物质代谢与GLP-1水平关系的文献并作综述。结果 GLP-1影响胰岛素的分泌及其敏感性,在糖代谢恢复中发挥主导作用。胃肠道营养物质代谢影响GLP-1水平。胃转流术(GBP)治疗2型糖尿病(T2DM)可能主要与其影响GLP-1水平有关。结论胃肠道营养物质代谢调控GLP-1水平在GBP治疗T2DM中起了重要作用,相应的深入研究将为T2DM的治疗开辟一个新的领域。     

胰高血糖素样肽-2对短肠大鼠残留小肠代偿的影响

目的研究胰高血糖素样肽-2(GLP-2)对短肠大鼠残留小肠形态及功能代偿的影响。方法将20只切除小肠75%的大鼠随机分成对照组和GLP-2组,术后1-5 d内自由进食。GLP-2组每日2次腹腔注射GLP-2(250μg·kg~(-1)·d~(-1))；对照组每日2次腹部皮下注射生理盐水0．5 ml；另设1组正常进食大鼠作空白对照。术后第6天行残留小肠黏膜形态学检测、细胞增殖核心抗原(PCNA)测定,钠葡萄糖共同转运体(SGLT1)和二肽转运体(PEPT1)的mRNA表达检测以及在体小肠循环灌流实验测定大鼠回肠的单位长度及单位重量的葡萄糖吸收率。结果GLP-2组残留小肠黏膜形态学指标、PCNA指数显著高于对照组；而小肠黏膜细胞凋亡显著低于对照组；残留回肠SGLT1和PEPT1的mRNA表达显著高于对照组；均P＜0．05。但两组灌洗段回肠每g湿重葡萄糖吸收率差异无统计学意义(P＞0．05)。结论GLP-2能刺激小肠黏膜上皮增生、抑制凋亡,促进短肠大鼠残留小肠黏膜的形态及功能代偿。     

胰岛素对烫伤血清诱导骨骼肌成肌细胞凋亡的调控作用

目的 探讨胰岛素对烫伤大鼠血清诱导大鼠骨骼肌成肌细胞株L6凋亡的调控作用及机制.方法 体外培养L6细胞,按照随机数字表法分为对照组、烫伤血清组、胰岛素组和烫伤血清+胰岛素组.在上述4组细胞培养液中分别添加体积分数20％正常大鼠血清、体积分数20％烫伤大鼠血清、体积分数20％正常大鼠血清+100 nmol/L胰岛素、体积分数20％烫伤大鼠血清+100 nmol/L胰岛素,孵育48 h.行Hoechst 33258染色,于倒置荧光显微镜下观察细胞凋亡形态并计数凋亡细胞;行膜联蛋白V-异硫氰酸荧光素/碘化丙啶双标记染色,用流式细胞仪检测细胞凋亡率;蛋白质印迹法检测细胞磷酸化(p一)蛋白激酶B(Akt)、p-磷脂酰肌醇3激酶(PI3K)、Bax、Bcl-2、活化半胱氨酸天冬氨酸蛋白酶3( caspase-3)的蛋白表达量.对实验数据行组间或配对t检验.结果 (1)倒置荧光显微镜下可见,烫伤血清组凋亡细胞为每视野(59.6±3 9)个,显著多于对照组、胰岛素组、烫伤血清+胰岛素组[每视野(4 9±2.6)、(5 5±2 1)、(19.7±2 3)个,t值分别为28.53、29.86、21.53,P值均小于0.01].(2)流式细胞仪检测结果显示,烫伤血清组细胞凋亡率为(18.5±1.8)％,明显高于对照组、胰岛素组及烫伤血清+胰岛素组[(1.1±0 6)％、(1 5±0 3)％、(7.8±0.6)％,t值分别为22.41、22 83、13 92,P值均小于0 01].(3)蛋白质印迹检测显示,烫伤血清组Bax蛋白表达量(1.12±0.63)及活化caspase-3蛋白表达量(2.15±0.51)明显高于对照组(0.16±0 03、0.21±0.03,t值分别为3 80、10 69,P值均小于0 01),p-Akt蛋白表达量(0.20±0.03)明显低于对照组(0 42±0 07,t=-8.46,P＜0.01);Bcl-2及p-PI3K蛋白表达量(0.19±0 03、0.17±0.03)与对照组(0.26±0 09、0 28±0.07)接近(t值分别为-2.73、-1.14,P值均大于0 05).与烫伤血清组比较,烫伤血清+胰岛素组Bax蛋白表达量(0.40±0.14)和活化caspase-3蛋白表达量(0.83±0.18)明显降低(t=-3.23,P ＜0.05;t =6.66,P ＜0.01),Bcl-2、p-Akt及p-PI3K蛋白表达量均升高(0.39±0.10、0 78±0 03、0.47±0.12,t值分别为4.07、18.71、5 05,P＜0.05或P＜0.01).结论 烫伤大鼠血清可显著促进骨骼肌成肌细胞凋亡,胰岛素能通过PI3K/Akt信号途径抑制细胞凋亡.     

Coagonist of glucagon-like peptide-1 and glucagon receptors ameliorates kidney injury in murine models of obesity and diabetes mellitus

AIM To investigate the role of glucagon-like peptide-1(GLP-1)/glucagon receptors coagonist on renal dysfunction associated with diabetes and obesity. METHODS Chronic high-fat diet fed C57 BL/6 J mice, streptozotocintreated high-fat diet fed C57 BL/6 J mice and diabeticC57 BLKS/J db/db mice were used as models of diabetes-induced renal dysfunction. The streptozotocintreated high-fat diet fed mice and db/db mice were treated with the GLP-1 and glucagon receptors coagonist(Aib2 C24 Chimera2, 150 μg/kg, sc) for twelve weeks, while in chronic high-fat diet fed mice, coagonist(Aib2 C24 Chimera2, 150 μg/kg, sc) treatment was continued for forty weeks. Kidney function, histology, fibrosis, inflammation, and plasma biochemistry were assessed at the end of the treatment. RESULTS Coagonist treatment decreased body weight, plasma lipids, insulin resistance, creatinine, blood urea nitrogen, urinary albumin excretion rate and renal lipids. In kidney, expression of lipogenic genes(SREBP-1 C, FAS, and SCD-1) was decreased, and expression of genes involved in β-oxidation(CPT-1 and PPAR-α) was increased due to coagonist treatment. In plasma, coagonist treatment increased adiponectin and FGF21 and decreased IL-6 and TNF-?. Coagonist treatment reduced expression of inflammatory(TNF-α, MCP-1, and MMP-9) and pro-fibrotic(TGF-β, COL1 A1, and α-SMA) genes and also improved histological derangement in renal tissue.CONCLUSION Coagonist of GLP-1 and glucagon receptors alleviated diabetes and obesity-induced renal dysfunction by reducing glucose intolerance, obesity, and hyperlipidemia.     

钙敏感受体缺失对小鼠成骨细胞增殖与分化的影响及机制研究

目的 探讨钙敏感受体(CaSR)在小鼠成骨细胞增殖与分化中的作用,以及Wnt信号通路在其促进成骨细胞增殖及分化过程中的调节作用. 方法 取新生同窝野生型小鼠(对照组)和CaSR敲除纯合子小鼠(实验组)各4只,分离培养颅骨成骨细胞并传至第3代,分别于培养2、4、6、8d时采用CCK-8法测定细胞的吸光度(OD)值,检测成骨细胞碱性磷酸酶(ALP)的活性.取培养6d的细胞行实时荧光定量-聚合酶链反应(RT-qPCR)检测核心结合因子(Runx2)、ALP、骨钙素(OCN)、核激活因子受体配体(RANKL)、骨保护素(OPG)及β-链蛋白的mRNA基因表达水平;采用Western Blot检测β-链蛋白、Wnt-5a、胰岛素样生长因子-1(IGF-1)、Runx2的蛋白表达水平. 结果 培养6d时对照组和实验组成骨细胞的OD值(1.55±0.05、1.26±0.02)和ALP活性[(0.023±0.002)、(0.017±0.001)U/mg· prot]均达到峰值,与其他时间点比较差异均有统计学意义(P＜0.05);同一时间点实验组成骨细胞的OD值和ALP活性均低于对照组,差异有统计学意义(P＜0.05).与对照组比较,培养6d时实验组成骨细胞的Runx2、ALP、OCN、RANKL/OPG、β-链蛋白的mRNA表达水平,以及β-链蛋白、Wnt-5a、IGF-1、Runx2的蛋白表达水平均显著降低,两组比较差异均有统计学意义(P＜0.05). 结论 CaSR缺失将导致成骨细胞的增殖和分化障碍,其机制可能与经典的Wnt信号通路抑制有关.     

Impact of the hepatic branch of the vagus and Roux-en-Y gastric bypass on the hypoglycemic effect and glucagon-like peptide-1 in rats with type 2 diabetes mellitus

Background

The impact of the hepatic branch of the vagus and Roux-en-Y gastric bypass (RYGB) on the hypoglycemic effect and glucagon-like peptide-1 (GLP-1) in rats with type 2 diabetes mellitus (T2DM) was investigated, and interactions were preliminarily analyzed.

Methods

A total of 45 rats with T2DM were divided into four groups: sham operation (S, n = 10), sham operation with the hepatic branch of the vagus resected (SV, n = 11), RYGB (n = 12), and RYGB without preservation of the vagus (RYGBV, n = 12). Body mass, fasting blood glucose (FBG), fasting serum insulin, and concentrations of fasting serum GLP-1 were examined in the first, second, fourth, and eighth week before and after surgery. The effects of RYGB and the hepatic branch of the vagus on GLP-1 levels in the eighth postoperative week were also analyzed.

Results

RYGB caused a significant reduction in the weight of rats with T2DM (P < 0.05), improved the levels of serum GLP-1 and insulin (P < 0.05), and decreased FBG level (P < 0.05). Retention of the hepatic branch of the vagus maintained weight reduction for a longer period (P < 0.05) and increased the levels of serum GLP-1 and insulin (P < 0.05), but had no impact on FBG level (P > 0.05).

Conclusions

RYGB had better therapeutic efficacy in rats with T2DM. Care should be taken during RYGB surgery to preserve the hepatic branch of the vagus.     

Prediction of the effect on antihyperglycaemic action of sitagliptin by plasma active form glucagon-like peptide-1

AIM: To investigate whether active glucagon-like peptide-1(GLP-1) is a prediction Factor of Effect of sitagliptin on patients with type 2 diabetes mellitus(GLP-1 FEST:UMIN000010645). METHODS: Seventy-six patients with type 2 diabetes, who had insufficient glycemic control [Hemoglobin A1c(Hb A1c) ≥ 7%] in spite of treatment with metformin and/or sulfonylurea, were included in the investigation. Patients were divided into three groups by tertiles of fasting plasma active GLP-1 level, before the administration of 50 mg sitagliptin. RESULTS: At baseline, body mass index, serum UA, insulin and HOMA-IR were higher in the high active GLP-1 group than in the other two groups. The high active GLP-1 group did not show any decline of Hb A1c(7.6% ± 1.4% to 7.5% ± 1.5%), whereas the middle and low groups indicated significant decline of Hb A1c(7.4 ± 0.7 to 6.8 ± 0.6 and 7.4 ± 1.2 to 6.9 ± 1.3, respectively) during six months. Only the low and middle groups showed a significant increment of active GLP-1, C-peptide level, a decreased log and proinsulin/insulin ratio after administration. In logistic analysis, the low or middle group is a significantexplanatory variable for an Hb A1 c decrease of ≥ 0.5%, and its odds ratio is 4.5(1.40-17.6)(P = 0.01) against the high active GLP-1 group. This remains independent when adjusted for Hb A1 c level before administration, patients' medical history, medications, insulin secretion and insulin resistance.CONCLUSION: Plasma fasting active GLP-1 is an independent predictive marker for the efficacy of dipeptidyl peptidase 4 inhibitor sitagliptin.