食源性肥胖对大鼠免疫功能的影响

发布时间：2018-06-29 22:11

本文选题：食源性肥胖 + 免疫　；参考：《天津医科大学》2009年硕士论文

【摘要】： 目的: 1建立食源性肥胖(diet induced obesity,DIO)SD大鼠模型,观察肥胖大鼠与非肥胖大鼠脾脏CD4~+和CD8~+T淋巴细胞含量的变化,探究肥胖对大鼠细胞免疫功能的影响。 2观察大鼠脾脏淋巴细胞表面是否存在长型的leptin受体(Ob-Rb)蛋白以及淋巴细胞内是否存在磷酸化的STAT3蛋白。 3观察肥胖大鼠与非肥胖大鼠脾脏淋巴细胞Ob-Rb-STAT3信号转导通路活性的差异,从而探究肥胖状态下机体免疫功能的变化是否由leptin通过Ob-Rb-STAT3信号转导通路作用引起。方法: 1利用高能量高脂肪饮食喂养大鼠14周后,将其与用普通饲料喂养的大鼠的体重进行比较,根据体重分为DIO组以及肥胖抵抗(diet resistant,DR)组。 2分别取对照组、DR组和DIO组大鼠的脾脏,将其制成脾细胞的单细胞悬液,再利用流式细胞术检测大鼠脾脏CD4~+和CD8~+T淋巴细胞在脾细胞中所占的百分比。 3分别提取对照组、DR组和DIO组大鼠脾细胞的蛋白,利用Western blot检测大鼠淋巴细胞表面的Ob-Rb蛋白以及淋巴细胞内磷酸化的STAT3蛋白的表达强度。结果: 1体重变化的结果:普通饲料喂养的对照组大鼠与高能量高脂肪饲料喂养的大鼠的初始平均体重相当,无显著性差异(P＞0.05)。经过14周不同饲料的喂养之后,高能饲料组大鼠的平均体重是对照组大鼠平均体重的122.1%,具有显著性差异(P＜0.001)。在高能饲料组中,10只体重最高的大鼠设为DIO组,体重最低的10只大鼠设为DR组,DIO组大鼠的平均体重是DR组大鼠的136.7%,具有显著性差异(P＜0.001)。 2三组大鼠脾细胞中CD4~+和CD8~+T淋巴细胞含量比较的结果:通过流式细胞术的检测发现与对照组和DR组相比较,DIO组大鼠脾细胞中CD4~+T淋巴细胞所占百分比变化并不明显,没有统计学差异(P＞0.05)。与对照组和DR组相比较,DIO组大鼠脾细胞中CD8~+T淋巴细胞所占百分比增加(P＜0.001)。上述CD4~+和CD8~+T淋巴细胞含量的变化导致DIO组大鼠脾脏CD4~+/CD8~+细胞比值低于DR组大鼠(P＜0.01)以及对照组大鼠(P＜0.001)。 3三组大鼠脾脏淋巴细胞Ob-Rb蛋白以及磷酸化的STAT3蛋白表达强度的比较:通过Western blot检测发现在各组大鼠脾脏淋巴细胞所提取的蛋白中,128-kDa以及82-kDa处可见明显蛋白表达条带,与预期分子量一致,表明Ob-Rb蛋白以及705位酪氨酸磷酸化的STAT3蛋白在大鼠脾脏淋巴细胞中都有不同程度的表达。利用UVP凝胶成像系统分析后,DIO组、DR组以及对照组的大鼠脾脏淋巴细胞表面Ob-Rb蛋白以及细胞内705位酪氨酸磷酸化的STAT3蛋白表达的密度值并没有统计学的差异(P＞0.05)。结论: 1经过14周高能量高脂肪的饲料喂养,SD大鼠能发展成为DIO大鼠和DR大鼠两种体重存在明显差异动物模型,这一结果的产生是由于DIO大鼠和DR大鼠调控自身体重的方式不同所造成的。 2流式细胞术的实验结果表明,与对照组和DR组相比较,DIO组大鼠的脾细胞中CD4~+T淋巴细胞所占百分比变化并不明显,CD8~+T淋巴细胞所占百分比增加,DIO组大鼠脾脏CD4~+/CD8~+细胞比值低于DR组以及对照组大鼠。这一实验结果表明,肥胖使大鼠处于免疫抑制状态,其细胞免疫功能降低,对感染的抵抗力下降,肥胖大鼠的易感性相应的增加。 3 Western blot的实验结果表明,Ob-Rb蛋白以及磷酸化的STAT3蛋白在大鼠脾脏淋巴细胞中都有不同程度的表达。DIO组、DR组以及对照组大鼠脾脏淋巴细胞表面的Ob-Rb蛋白以及细胞内磷酸化的STAT3蛋白表达的强度并没有明显的差异。这一实验结果说明,DIO大鼠细胞免疫功能的下降与其脾脏淋巴细胞中的Ob-Rb-STAT3信号转导通路并没有直接的关系。
[Abstract]:Objective:
1 the diet induced obesity (DIO) SD rat model was established to observe the changes of CD4~+ and CD8~+T lymphocytes in the spleen of obese rats and non obese rats, and to explore the effect of obesity on the cellular immune function of rats.
2 to observe whether there is long leptin receptor (Ob-Rb) protein on the surface of spleen lymphocytes and whether phosphorylated STAT3 protein exists in lymphocytes.
3 observe the difference in the activity of Ob-Rb-STAT3 signal transduction pathway in the spleen lymphocytes of obese rats and non obese rats, and to explore whether the changes of immune function in the body of obesity are caused by the role of leptin through the Ob-Rb-STAT3 signal transduction pathway.
Method:
1 after 14 weeks of high energy and high fat diet, the rats were compared with the body weight of rats fed with ordinary diet, and the body weight was divided into DIO group and diet resistant (DR) group.
2 the spleen of the control group, the DR group and the DIO group were respectively made into the single cell suspension of the spleen cells, and the percentage of the spleen CD4~+ and the CD8~+T lymphocyte in the spleen cells was detected by flow cytometry.
3 the protein of the spleen cells in the control group, the DR group and the DIO group, and the Western blot were used to detect the Ob-Rb protein on the surface of the rat lymphocyte and the expression intensity of the phosphorylated STAT3 protein in the lymphocyte.
Result:
1 the results of body weight change: the average weight of the rats fed with the normal diet was equal to the rats fed with high energy and high fat feed, and there was no significant difference (P > 0.05). After 14 weeks of feeding, the average weight of the rats in the high energy diet group was 122.1% of the control group (P 0.001). In the high energy diet group, 10 rats with the highest weight were set as DIO group, and the 10 rats with the lowest weight were set as group DR, and the average weight of group DIO was 136.7% in group DR (P < 0.001).
2 Comparison of the content of CD4~+ and CD8~+T lymphocytes in the splenocytes of the three groups: compared with the control group and the DR group by flow cytometry, the percentage of CD4~+T lymphocyte in the spleen cells of the DIO group was not significantly different (P > 0.05). Compared with the control group and the DR group, the spleen cells of the DIO group rats were compared with the control group and the DR group. The percentage of CD8~+T lymphocytes increased (P < 0.001). The changes in the content of CD4~+ and CD8~+T lymphocytes in the DIO group were lower than that of the DR group (P < 0.01) and the control group (P < 0.001).
3 Comparison of the expression intensity of Ob-Rb protein and phosphorylated STAT3 protein in the spleen lymphocytes of the three groups of rats: through Western blot detection, it was found that in the protein extracted from the spleen lymphocytes of the rats of each group, the obvious protein bands were found at 128-kDa and 82-kDa, which was consistent with the expected molecular weight, indicating the Ob-Rb protein and 705 tyrosine phosphorus. The acidified STAT3 protein had different degrees of expression in the spleen lymphocytes of rats. After the analysis of the UVP gel imaging system, there was no statistical difference in the density of Ob-Rb protein on the surface of spleen lymphocyte and the expression of 705 tyrosine phosphorylation of STAT3 protein in the rats of DIO, DR and control groups (P > 0.05).
Conclusion:
1 after 14 weeks of high energy and high fat feed, SD rats were able to develop into DIO rats and DR rats with significant differences in animal models. This result was caused by different ways of regulating the body weight of DIO rats and DR rats.
The results of 2 flow cytometry showed that compared with the control group and the DR group, the percentage of CD4~+T lymphocyte in the spleen cells of the DIO group was not obvious, the percentage of CD8~+T lymphocytes increased, and the ratio of CD4~+/CD8~+ cells in the spleen of the DIO group was lower than that of the DR group and the control group. Mice are in an immunosuppressive state, their cellular immune function is reduced, their resistance to infection is reduced, and the susceptibility of obese rats increases correspondingly.
The experimental results of 3 Western blot showed that the Ob-Rb protein and the phosphorylated STAT3 protein had different levels of.DIO in the spleen lymphocytes of rats. There was no significant difference between the Ob-Rb protein on the surface of the spleen lymphocyte and the intensity of the phosphorylated STAT3 protein expression in the spleen lymphocytes of the DR group and the control group. The results showed that the decrease of cellular immune function in DIO rats was not directly related to the Ob-Rb-STAT3 signal transduction pathway in splenic lymphocytes.
【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2009
【分类号】：R392.12

【共引文献】