高糖對內(nèi)毒素炎癥反應(yīng)的影響及其機制研究
發(fā)布時間：2019-03-24 11:36
【摘要】：背景 心血管病變是糖尿病的主要并發(fā)癥和致死原因,而動脈粥樣硬化是其心血管并發(fā)癥的主要病理表現(xiàn)。大量的研究證實,2型糖尿病和動脈粥樣硬化可能是同一病理生理基礎(chǔ)上平行發(fā)展的兩種疾病,它們的共同基礎(chǔ)是慢性亞臨床炎癥。雖然已證實,糖尿病患者血液中多種炎性介質(zhì)均呈明顯增高趨勢,但其炎癥發(fā)生的真正原因還不明了。最新的研究表明,細菌來源的脂多糖(lipopolysaccharide, LPS)可能是引起糖尿病慢性亞臨床炎癥的真正始發(fā)因子。腸道是人體最大的細菌和LPS貯存場所。由于正常人體腸上皮細胞能作為物理及功能上的屏障以防止LPS轉(zhuǎn)位,因此正常人體血液中的LPS水平非常低。所以我們推測,糖尿病血液LPS增加可能與腸上皮屏障功能減弱導(dǎo)致LPS轉(zhuǎn)位有關(guān)。此外,糖尿病患者與健康人相比,受LPS刺激時所引發(fā)的炎癥反應(yīng)更加強烈。目前,已有大量證據(jù)顯示糖尿病患者內(nèi)皮功能異常是血管并發(fā)癥的始發(fā)因素,且在心血管疾病的炎癥機制中起了重要的作用。故我們推測,高糖條件下,血管內(nèi)皮細胞對LPS刺激更為敏感。 目的 1.闡明高脂飲食誘導(dǎo)的胰島素抵抗小鼠其血液LPS水平的升高是否與腸上皮細胞增殖能力下降引起的腸道屏障功能改變有關(guān)。 2.明確高糖能否加重LPS誘導(dǎo)的血管內(nèi)皮細胞的炎癥反應(yīng)并探究其可能機制。 方-法 1.動物實驗部分：用高脂飲食誘發(fā)小鼠胰島素抵抗模型。ELISA法測定血清LPS水平。利用穩(wěn)態(tài)模型評價胰島素抵抗指數(shù)。D-木糖吸收實驗測定腸黏膜通透性。免疫組織化學(xué)法觀察Brdu染色陽性的細胞數(shù),計算腸上皮細胞的增殖指數(shù)。 2.細胞實驗部分：人臍靜脈內(nèi)皮細胞(Human umbilical vein endothelial cells, HUVECs)用不同濃度的葡萄糖(5.5,25,50mmol/L)和/或不同濃度的LPS(0,10,100,1000gg/L)孵育24h。ELISA法測定培養(yǎng)上清液中IL-6和TNF-a水平。Western blot去測定目標蛋白表達。 結(jié)果 1.動物實驗部分：高脂飼料喂養(yǎng)8周后小鼠胰島素抵抗指數(shù)明顯高于正常對照組,血清LPS水平明顯增高,小鼠對D-木糖吸收量明顯增加(P0.01)；高脂飼料喂養(yǎng)8周后小鼠空腸隱窩中平均BrDu陽性細胞數(shù)減少,BrDu陽性細胞百分比下降(P0.01)。 2.細胞實驗部分：與正常糖濃度組相比,細胞在高糖環(huán)境下,同樣濃度的LPS引起的血管內(nèi)皮細胞上清TNF-a和IL-6水平明顯增高(P0.05)。雖然單純25mmol/L高糖或100μg/L LPS孵育細胞對TLR2蛋白表達無明顯影響,但兩者共同孵育細胞,可誘導(dǎo)TLR2表達顯著增加。而各組TLR4的表達卻無顯著變化。提示高糖和LPS對TLR2的表達有協(xié)同作用。此外,高糖和LPS共同孵育血管內(nèi)皮細胞后,細胞核內(nèi)NF-κB蛋白表達也顯著增加(P0.01)。 結(jié)論 1.高脂飲食誘導(dǎo)的小鼠代謝性內(nèi)毒素血癥可能與腸上皮細胞的增殖修復(fù)能力下降引起的腸道屏障功能改變有關(guān)。 2.高糖可加重LPS誘導(dǎo)的血管內(nèi)皮細胞炎癥反應(yīng),其機制可能與高血糖誘導(dǎo)的NF-κB依賴性TLR2表達增加有關(guān)。
[Abstract]:background Cardiovascular disease is the main complication and cause of diabetes, and atherosclerosis is the main pathological form of its cardiovascular complications. A large number of studies have shown that type 2 diabetes and atherosclerosis may be two types of diseases that are parallel to the same pathophysiology, and their common basis is chronic subclinical inflammation. The number of inflammatory mediators in the blood of patients with diabetes has been shown to be significantly higher, but the true cause of its inflammation is unknown Recent studies have shown that lipopolysaccharides (LPS) of bacterial origin may be the true origin of the chronic subclinical inflammation of diabetes. The intestinal tract is the largest bacterial and LPS storage site in the human body The normal human intestinal epithelial cells can be used as a physical and functional barrier to prevent the translocation of LPS, so the level of LPS in normal human blood is very high, Low. So we have speculated that the increase in the LPS of the diabetic blood may be associated with a decrease in the function of the intestinal epithelial barrier, which results in the translocation of the LPS Off. In addition, the inflammatory response induced by LPS stimulation is more intense in patients with diabetes compared to healthy controls Currently, there is a large amount of evidence that the endothelial dysfunction in the diabetic patients is an initiating factor for vascular complications and plays an important role in the inflammatory mechanism of the cardiovascular disease It is suggested that the vascular endothelial cells are more sensitive to the stimulation of LPS in the presence of high glucose. A sense of feeling. Objective:1. To clarify whether the insulin resistance induced by high-fat diet is related to the intestinal barrier work caused by the decrease in the level of the blood LPS and the decrease of the proliferation ability of the intestinal epithelial cells. 2. clarify whether high glucose can aggravate the inflammatory response of LPS-induced vascular endothelial cells and explore Possible mechanism.-method 1. Animal experiment part: high-fat diet induced mouse insulin resistance model. ELIS A method for determination of serum LPS level. Steady state model evaluation of insulin resistance index. D-xylose absorption The number of cells positive for Brdu staining was observed by immunocytochemical method, and the number of cells positive for Brdu staining was measured by immunohistochemistry. Cell experiment: Human umbilical vein endothelial cells (HUVECs) were incubated with different concentrations of glucose (5.5,25,50 mmol/ L) and/ or different concentrations of LPS (0,10,100,1000 mmol/ L) for 24 h. Serum IL-6 and TNF-a levels. Bl Results 1. The experimental part of the animal: The insulin resistance index of the mice was significantly higher than that of the normal control group after 8 weeks of high-fat feed, and the level of the serum LPS increased significantly. -The uptake of xylose was significantly increased (P0.01); the mean number of BrDu-positive cells in the crypt of the jejunum of mice after 8 weeks of high-fat diet was reduced, and BrD The percentage of u-positive cells decreased (P0.01). A and IL-6 levels were significantly higher (P0.05). Although the expression of TLR2 protein was not significantly affected by 25 mmol/ L high glucose or 100. m u.g/ L of LPS, both of them Compared with the incubation cells, the expression of TLR2 can be induced to be significant There was no significant change in the expression of TLR4 in each group. High glucose and LPS have a synergistic effect on the expression of TLR2. In addition, after incubation of the vascular endothelial cells by high glucose and LPS, NF -I'm sorry. Conclusion 1. The metabolic endotoxemia induced by high-fat diet may be closely related to the intestinal epithelium. 2. High glucose can aggravate the inflammatory response of LPS-induced vascular endothelial cells, and its mechanism may
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：R363
本文編號：2446296
[Abstract]:background Cardiovascular disease is the main complication and cause of diabetes, and atherosclerosis is the main pathological form of its cardiovascular complications. A large number of studies have shown that type 2 diabetes and atherosclerosis may be two types of diseases that are parallel to the same pathophysiology, and their common basis is chronic subclinical inflammation. The number of inflammatory mediators in the blood of patients with diabetes has been shown to be significantly higher, but the true cause of its inflammation is unknown Recent studies have shown that lipopolysaccharides (LPS) of bacterial origin may be the true origin of the chronic subclinical inflammation of diabetes. The intestinal tract is the largest bacterial and LPS storage site in the human body The normal human intestinal epithelial cells can be used as a physical and functional barrier to prevent the translocation of LPS, so the level of LPS in normal human blood is very high, Low. So we have speculated that the increase in the LPS of the diabetic blood may be associated with a decrease in the function of the intestinal epithelial barrier, which results in the translocation of the LPS Off. In addition, the inflammatory response induced by LPS stimulation is more intense in patients with diabetes compared to healthy controls Currently, there is a large amount of evidence that the endothelial dysfunction in the diabetic patients is an initiating factor for vascular complications and plays an important role in the inflammatory mechanism of the cardiovascular disease It is suggested that the vascular endothelial cells are more sensitive to the stimulation of LPS in the presence of high glucose. A sense of feeling. Objective:1. To clarify whether the insulin resistance induced by high-fat diet is related to the intestinal barrier work caused by the decrease in the level of the blood LPS and the decrease of the proliferation ability of the intestinal epithelial cells. 2. clarify whether high glucose can aggravate the inflammatory response of LPS-induced vascular endothelial cells and explore Possible mechanism.-method 1. Animal experiment part: high-fat diet induced mouse insulin resistance model. ELIS A method for determination of serum LPS level. Steady state model evaluation of insulin resistance index. D-xylose absorption The number of cells positive for Brdu staining was observed by immunocytochemical method, and the number of cells positive for Brdu staining was measured by immunohistochemistry. Cell experiment: Human umbilical vein endothelial cells (HUVECs) were incubated with different concentrations of glucose (5.5,25,50 mmol/ L) and/ or different concentrations of LPS (0,10,100,1000 mmol/ L) for 24 h. Serum IL-6 and TNF-a levels. Bl Results 1. The experimental part of the animal: The insulin resistance index of the mice was significantly higher than that of the normal control group after 8 weeks of high-fat feed, and the level of the serum LPS increased significantly. -The uptake of xylose was significantly increased (P0.01); the mean number of BrDu-positive cells in the crypt of the jejunum of mice after 8 weeks of high-fat diet was reduced, and BrD The percentage of u-positive cells decreased (P0.01). A and IL-6 levels were significantly higher (P0.05). Although the expression of TLR2 protein was not significantly affected by 25 mmol/ L high glucose or 100. m u.g/ L of LPS, both of them Compared with the incubation cells, the expression of TLR2 can be induced to be significant There was no significant change in the expression of TLR4 in each group. High glucose and LPS have a synergistic effect on the expression of TLR2. In addition, after incubation of the vascular endothelial cells by high glucose and LPS, NF -I'm sorry. Conclusion 1. The metabolic endotoxemia induced by high-fat diet may be closely related to the intestinal epithelium. 2. High glucose can aggravate the inflammatory response of LPS-induced vascular endothelial cells, and its mechanism may
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：R363
【參考文獻】
相關(guān)期刊論文 前4條
1 康怡;陸菊明;孫敬芳;李春霖;王先令;張小群;呂朝暉;竇京濤;母義明;;不同糖調(diào)節(jié)受損人群的餐后血糖波動特點研究[J];解放軍醫(yī)學(xué)雜志;2009年05期
2 劉月潔,吳艷君;糖尿病患者血管內(nèi)皮功能損傷的發(fā)生機制[J];臨床超聲醫(yī)學(xué)雜志;2003年01期
3 鄭鳴之;范瑩;孟香紅;朱立;沈岳良;陳瑩瑩;;高糖通過環(huán)加氧酶2依賴性途徑誘導(dǎo)GRP78表達改變[J];中國病理生理雜志;2009年08期
4 黃敬澤;王健;;血糖波動對2型糖尿病患者血管內(nèi)皮損傷的影響[J];中國老年學(xué)雜志;2010年21期
，本文編號：2446296
本文鏈接：http://sikaile.net/xiyixuelunwen/2446296.html
最近更新
教材專著
