炎症对脂肪细胞功能的影响及其机制探讨

发布时间：2018-06-19 14:37

本文选题：肿瘤坏死因子 + 脂肪细胞　；参考：《中南大学》2007年博士论文

【摘要】： 目的肿瘤坏死因子α(TNF-α)作为促炎因子对脂肪细胞功能有多方面的影响，包括促进细胞分化、脂解及脂肪因子分泌等。本文拟研究TNF-α对传代培养的兔皮下脂肪细胞胆固醇流出功能的影响，及可能的作用机制。方法来源于兔腹股沟皮下的脂肪细胞以不同浓度的TNF-α(5，10，20 ng／ml)干预24小时。用液体闪烁计数仪测量脂肪细胞对氚标胆固醇的流出率。用逆转录多聚酶链式反应(RT-PCR)检测过氧化物酶体增殖物激活受体γ(PPARγ)、肝X受体α(LXRα)及三磷酸腺苷结合盒转运体A1(ABCA1)的mRNA表达。结果 1．5或10 ng／ml TNF-α干预脂肪细胞24小时，可使胆固醇流出率增加，且10 ng／ml TNF-α作用最强(7.03±1.17％)，较对照组(3.92±0.46％)明显增高。但20 ng／ml TNF-α反而使胆固醇流出率较10 ng／ml时下降了16.2％(P＜0.05)。 2．5或10 ng／ml TNF-α可上调ABCA1表达，其表达量分别为0.44±0.17和0.91±0.26，与对照组0.20±0.06相比差异有显著性。20 ng／ml TNF-α使ABCA1表达有所下降(0.69±0.13)。与此同时，TNF-α可调节脂肪细胞PPARγ和LXRα表达。在TNF-α≤10 ng／ml时起促进作用，在20 ng／ml时起抑制作用。 3．预先以PPARγ特异性抑制剂GW9662孵育半小时，可抑制10 ng／ml TNF-α对PPARγ(0.88±0.22 vs 1.37±0.25，P＜0.05)和LXRα(0.51±0.14 vs 0.32±0.08，P＜0.05)的诱导作用。结论 TNF-α影响脂肪细胞胆固醇流出及其ABCA1表达，这种作用与TNF-α对脂肪细胞PPARγ-LXRα的双重调节作用有关。目的脂肪细胞肥大伴随一系列功能改变。我们拟研究在氧化低密度脂蛋白(oxLDL)诱导脂肪细胞负荷脂质后，TNF-α对其胆固醇流出和ABCA1表达的影响是否会发生改变。方法用50μg／ml oxLDL孵育脂肪细胞24小时制造荷脂模型。再以不同浓度TNF-α(5，，10，20 ng／ml)干预24小时，观察胆固醇流出变化及用RT-PCR法检测脂肪细胞PPARγ、LXRα和ABCA1 mRNA表达。结果 1．OxLDL可使脂肪细胞胆固醇流出增加(7.46±2.34％vs 3.92±0.46％)，PPARγ(1.07±0.26 vs 0.48±0.12)、LXRα(0.83±0.16vs 0.32±0.08)和ABCA1(1.19±0.32 vs 0.20±0.06)表达上升，P均＜0.05。 2．TNF-α抑制荷脂脂肪细胞胆固醇流出，10 ng／ml时作用最强(6.02±0.31％vs3.92±0.46％)，在20 ng／ml时脂肪细胞胆固醇流出率略有回升(6.12±0.53)，差异有显著性。 3．从5 ng／ml到20 ng／ml TNF-α，PPARγ表达量分别为0.93±0.21，0.77±0.15，0.60±0.16与oxLDL对照组1.07±0.26相比表达降低。LXRα表达量为0.72±0.19，0.61±0.17，0.49±0.09与oxLDL对照组0.83±0.16相比也有降低。TNF-α呈浓度依赖性抑制脂肪细胞PPARγ和LXRα表达。5 ng／ml和10 ng／ml TNF-α分别使脂肪细胞ABCA1表达下降了14.4％和34.5％，20ng／ml TNF-α使ABCA1表达有所回升。结论在oxLDL诱导荷脂的脂肪细胞中，TNF-α对PPARγ和LXRα表达主要表现为抑制作用，并在一定程度上影响到ABCA1表达及脂肪细胞胆固醇流出。目的姜黄素是一类中药提取物，已证实其具有抗炎、抗氧化及改善血脂异常等作用。本研究观察了姜黄素对脂肪细胞抗炎脂肪因子脂联素表达和分泌的影响，初步评价姜黄素对脂肪细胞功能的影响。方法新西兰大白兔腹股沟皮下脂肪细胞以不同浓度姜黄素(5，10，20μg／ml)孵育24小时，用ELISA试剂盒检测细胞培养上清液脂联素水平，并用RT-PCR方法检测脂联素及其上游因子PPARγ的表达。结果 5μg／ml至20μg／ml姜黄素分别使兔皮下脂肪细胞脂联素分泌水平较对照组(3.13±0.21μmol／l)增加(3.93±0.26，4.49±0.34，5.21±0.39μmol／l)。脂联素mRNA表达也较对照组(0.40±0.10)增加(0.55±0.09，0.66±0.11，0.80±0.13)。姜黄素促进PPARγ表达的作用与脂联素表达的改变一致，并在20μg／ml时达到最大(1.01±0.15vs 0.48±0.12，P＜0.05)。结论姜黄素可促进兔皮下脂肪细胞脂联素的表达和分泌，这种作用与其上调脂肪细胞PPARγ表达有关。
[Abstract]:objective
Tumor necrosis factor alpha (TNF- alpha), as a pro-inflammatory factor, has many effects on the function of adipocyte, including promoting cell differentiation, lipo secretion and adipose factor secretion. This paper intends to study the effect of TNF- alpha on the cholesterol efflux function of subcutaneous adipocytes in subcutaneous subcutaneous tissue and the possible mechanism of action.
Method
The adipocytes derived from the rabbit groin were interfered with different concentrations of TNF- alpha (5,10,20 ng / ml) for 24 hours. The efflux rate of tritium cholesterol was measured by the liquid scintillation counting instrument. The peroxisome proliferator activated receptor gamma (PPAR gamma), the liver X receptor alpha (LXR a) and the three phosphoric acid were detected by the reverse transcription polymerase chain reaction (RT-PCR). MRNA expression of adenosine binding cassette transporter A1 (ABCA1).
Result
1.5 or 10 ng / ml TNF- alpha could increase the cholesterol efflux rate for 24 hours, and 10 ng / ml TNF- alpha was strongest (7.03 + 1.17%), which was significantly higher than that in the control group (3.92 + 0.46%), but the cholesterol efflux rate decreased by 16.2% (P < 0.05) compared to 10 ng / ml.
2.5 or 10 ng / ml TNF- alpha could up regulate the expression of ABCA1, and the expression amount was 0.44 + 0.17 and 0.91 + 0.26 respectively. Compared with the control group 0.20 + 0.06, there was a significant difference between.20 ng / ml TNF- a to decrease the ABCA1 expression (0.69 + 0.13). Meanwhile, TNF- a could regulate the expression of PPAR gamma and LXR alpha in adipocytes. The inhibitory effect of 20 ng / ml.
3. the induction effect of 10 ng / ml TNF- alpha on PPAR gamma (0.88 + 0.22 vs 1.37 + 0.25, P < 0.05) and LXR alpha (0.51 + 0.14 vs 0.32 + 0.08, P < 0.05) can be inhibited by pre incubation of PPAR gamma specific inhibitor.
conclusion
TNF- alpha affects the cholesterol efflux and ABCA1 expression in adipocytes, which is related to the dual regulation of TNF- alpha on PPAR -LXR -LXR of adipocytes.
objective
Adipocyte hypertrophy is accompanied by a series of functional changes. We intend to study whether the effect of TNF- alpha on the cholesterol efflux and the expression of ABCA1 after the oxidative low density lipoprotein (oxLDL) induced lipid cell load may change.
Method
Fat cells were incubated with 50 g / ml oxLDL for 24 hours to produce a fat charge model, and then 24 hours were intervened with different concentrations of TNF- alpha (5,10,20 ng / ml). The changes in cholesterol efflux were observed and the expression of PPAR gamma, LXR A and ABCA1 mRNA were detected by RT-PCR method.
Result
1.OxLDL could increase the cholesterol efflux of adipocytes (7.46 + 2.34%vs 3.92 + 0.46%), PPAR gamma (1.07 + 0.26 vs 0.48 + 0.12), LXR alpha (0.83 + 0.16vs 0.32 + 0.08) and ABCA1 (1.19 + 0.32 vs 0.20 +%) and P < 0.05.
2.TNF- alpha inhibited the cholesterol efflux of fat charged fat cells. The effect of 10 ng / ml was the strongest (6.02 + 0.31%vs3.92 + 0.46%). The cholesterol efflux rate of adipocytes was slightly increased at 20 ng / ml (6.12 + 0.53), and the difference was significant.
3. from 5 ng / ml to 20 ng / ml TNF- a, PPAR gamma expression was 0.93 + 0.21,0.77 + 0.16 compared with oxLDL control group 1.07 + 0.26, and the expression of.LXR a decreased to 0.72 + 0.19,0.61 + 0.17,0.49 + 0.09 and 0.83 + 5. Ng / ml and 10 ng / ml TNF- alpha reduced the expression of ABCA1 in adipocytes by 14.4% and 34.5% respectively, and 20ng / ml TNF- increased the expression of ABCA1.
conclusion
In the adipocytes induced by oxLDL, the expression of TNF- alpha on PPAR gamma and LXR alpha is mainly inhibited, and to a certain extent, it affects the expression of ABCA1 and the cholesterol efflux of adipocytes.
objective
Curcumin is a kind of traditional Chinese medicine extract, which has been proved to have anti-inflammatory, antioxidation and improvement of blood lipid abnormality. This study observed the effect of curcumin on the expression and secretion of adipocyte adiponectin in adipocytes, and preliminarily evaluated the effect of curcumin on the function of adipocytes.
Method
The subcutaneous fat cells in the groin of New Zealand rabbits were incubated with curcumin (5,10,20 / g / ml) for 24 hours. The level of adiponectin in cultured supernatant was detected by ELISA kit, and the expression of adiponectin and its upstream factor PPAR y was detected by RT-PCR.
Result
5 g / ml to 20 g / ml curcumin increased adiponectin secreting level in subcutaneous adipocytes (3.13 + 0.21 Mu mol / L) (3.93 + 0.26,4.49 + 0.34,5.21 + 0.39 UU / L). The mRNA expression of adiponectin was also increased (0.40 + 0.10) (0.55 + 0.09,0.66 + 0.13). The change of expression was consistent, and reached the maximum at 20 g / ml (1.01 + 0.15vs 0.48 + 0.12, P < 0.05).
conclusion
Curcumin can promote the expression and secretion of adiponectin in rabbit subcutaneous adipocytes, which is related to upregulated the expression of PPAR gamma in adipocytes.
【学位授予单位】：中南大学
【学位级别】：博士
【学位授予年份】：2007
【分类号】：R589.2;R363

【参考文献】