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1.
目的 探讨脂肪组织炎症在CYP1B1基因缺失小鼠保护营养性肥胖及其胰岛素抵抗中的作用和可能机制.方法 选择3周龄SPF级CYP1B1基因敲除(KO)和野生型(WT)雄性小鼠各16只,给予低(LFD)、高脂肪(HFD)饲料,每组8只,连续喂养11周.采用实时定量RT-PCR测定脂肪组织中巨噬细胞相关炎症因子、胰岛素通路中...  相似文献   

2.
目的 探讨血管新生因子血管生成素Ⅰ和Ⅱ在保护幼年细胞色素P4501 B1(CYP1 B1)基因敲除小鼠营养性肥胖中作用.方法 CYP1 B1基因敲除和野生型雄性C57/BL小鼠(3周龄)各16只,给予低脂膳食(10%脂肪)、高脂膳食(60%脂肪)饲料11周;小鼠处死后取附睾脂肪组织检测血管密度及血管新生因子基因和蛋白表达.结果 野生高脂组小鼠脂肪组织血管密度下降,基因敲除小鼠脂肪组织血管分布不受影响;高脂膳食诱导下,野生型和基因敲除小鼠血小板-内皮细胞粘附分子CD31 mRNA表达下调(P<0.05),野生型小鼠CD31蛋白表达下调(P<0.05);与野生低脂组比较,高脂诱导后野生型和基因敲除小鼠血管生成素Ⅰ表达量分别为0.35和0.50(P <0.05),瘦素表达量则分别为2.48和1.42(P<0.05);敲除高脂组瘦素表达量较野生高脂组下降(P<0.05).结论 CYP1B1基因敲除对血管新生相关因子的调控可能在其营养性肥胖中起一定保护作用.  相似文献   

3.
刘小聪  赵丽华  冯婧  Colin RJ  王素青 《营养学报》2012,34(2):143-146,149
目的探讨CYP1B1对高脂膳食诱导的成年小鼠脂肪代谢的作用。方法 CYP1B1基因敲除(KO)和野生型(WT)雄性成年C57/BL小鼠(6 w龄)各16只,给予低脂(LFD,30%)、高脂肪(HFD,60%)饲料共6 w。小鼠处死后取血清、附睾脂肪和肝脏组织检测相应的生化和分子生物学指标。结果 6 w高脂膳食后,KO小鼠能量摄入总量稍高于WT小鼠,但其体重增量和附睾脂肪组织重量均显著低于WT小鼠;WT小鼠脂肪细胞直径明显大于KO小鼠,且血糖、血清及肝脏组织中甘油三酯(TG)水平亦明显高于KO小鼠;肝脏组织RT-PCR结果显示,CYP1B1基因敲除后,启动脂肪形成的核因子及脂肪合成相关基因如CD36、SREBP1c、SCD1等表达下降,而调控脂肪氧化分解的基因如CPT-1α,UCP-2表达显著上升;蛋白印迹结果显示,CYP1B1基因敲除增强腺苷-磷酸激酶(AMPK)的磷酸化。结论 CYP1B1基因敲除对成年小鼠营养性肥胖的保护作用可能与AMPK磷酸化增强并调控肝脏中脂肪代谢相关基因的表达有关。  相似文献   

4.
目的 从整体水平探讨基因CYP1B1在机体脂肪代谢中的作用.方法 选择3周龄SPF级CYP1B1基因敲除(KO)和野生型(WT)雄性小鼠各16只,给予低(LFD)、高脂肪(HFD)饲料,每组8只.连续喂养11周.测定血清中甘油三酯(TG)的含量和肝脏组织中过氧化物酶体增殖物激活受体(PPAR-γ)、脂肪酸转移酶(CD3...  相似文献   

5.
目的 探究Plin1基因敲除对肥胖小鼠脂肪组织炎症水平的作用及其可能分子机制。方法 将雄性野生型C57BL/6J小鼠和Plin1基因敲除小鼠随机分为普通饲料组和高脂饲料组4组(n=6),喂养12 w后,隔夜禁食自由饮水12h,眼眶采取所有新鲜血液及组织样本,并颈椎脱臼处死,取各组小鼠血清及部分附睾脂肪组织,酶法测定小鼠血清中游离脂肪酸(nonesterified fatty acid,NEFAs)的水平;酶联免疫吸附法(enzyme-linked immunosorbent assay,ELISA)试验测定小鼠血清和脂肪组织中肿瘤坏死因子α(tumor necrosis factor alpha,TNF-α)、白细胞介素6(Interleukin-6,IL-6)及单核细胞趋化因子1(monocyte chemotactic protein-1,MCP-1)的水平;免疫组织化学染色法观测F4/80的表达程度;免疫荧光染色法和Western blot法观察核因子κB (Nuclear Factor kappa-B,NF-κB)亚基P65的转位及表达水平和NF-κB亚基P65表达及磷酸化差异...  相似文献   

6.
目的观察SR-AⅠ/Ⅱ基因敲除小鼠白色脂肪组织中β3-AR mRNA的表达,探讨其与SR-AⅠ/Ⅱ基因敲除小鼠肥胖易感的关系。方法应用荧光定量RT-PCR检测小鼠附睾周白色脂肪组织中β3-AR mRNA的表达;图像分析法评估附睾周脂肪细胞形态学变化;酶法检测TG、TC、LDL-C等血脂水平。结果:SR-AⅠ/Ⅱ基因敲除小鼠白色脂肪组织β3-AR mRNA表达量低于野生对照小鼠;血清TG、TC、LDL-C水平高于野生系对照小鼠;附睾周脂肪细胞面积和直径均大于对照小鼠。结论:SR-AⅠ/Ⅱ基因敲除小鼠对膳食诱导的肥胖易感可能与其白色脂肪组织β3-AR mRNA表达降低有关。  相似文献   

7.
目的观察芦丁对高脂饮食诱导的SAMP8小鼠血脂、糖耐量(GTT)、胰岛素耐量(ITT)及脂肪组织代谢相关蛋白的影响。方法将24只SAMP8小鼠随机分为低脂饲料(LFD)、高脂饲料(HFD)、高脂+芦丁(HR)共3组,每组8只。饲养18w后,进行糖耐量和胰岛素耐量实验,然后称重并处死,取血清测定甘油三酯、总胆固醇和甘油水平,取皮下和附睾脂肪组织用于蛋白检测。结果与LFD组相比,HFD组小鼠附睾脂肪组织重量、GTT和ITT血糖曲线下面积(AUC)显著增加(P0.05)。HR组小鼠ITTAUC较HFD组显著降低(P0.05)。在皮下和附睾脂肪组织中,与LFD组相比,HFD组P-Aktser473和P-AMPK蛋白表达量均显著降低(P0.05);HR组皮下脂肪组织P-AMPK和附睾脂肪组织P-Aktser473较HFD组显著升高(P 0.05);各组间TNFα蛋白表达量无显著差异(P0.05)。结论芦丁能够改善高脂饲养SAMP8小鼠胰岛素耐量受损状况。且芦丁干预能够升高脂肪组织P-Aktser473和P-AMPK蛋白表达,但是随脂肪组织部位不同而存在差异。  相似文献   

8.
目的 观察脂联素基因敲除小鼠主动脉组织病理学和组织化学的特性. 方法 SPF级6周龄雄性脂联素基因敲除小鼠纯合子(Adiponectin-/-)30只随机分为5组,第1、2、3组分别给予普通膳食喂养10、20、30周,第4组每2周经颈静脉注射空白腺病毒载体(即β-半乳糖甘酶腺病毒载体)并予普通膳食喂养30周,第5组每2周经颈静脉注射重组脂联素腺病毒载体并予普通膳食喂养30周;另随机选取SPF、级6周龄雄性野生型小鼠(WT)6只为正常对照组,给予普通膳食喂养30周.采用酶法测定血糖浓度,放射免疫法测定血浆胰岛素和脂联素水平.分离小鼠胸主动脉置4%多聚甲醛固定,石蜡包埋,连续切片,行茜素红钙化染色.分离主动脉弓到髂骨分支的动脉,用比色法测定10%甲酸抽提的钙含量.超声破碎胸主动脉,用Bradford法测总蛋白含量,离心后取上清液采用对硝基苯酚法测定ALP活性. 结果经普通膳食喂养的各组脂联素基因敲除小鼠与野生型小鼠在体重、血糖、血胰岛素水平方面无明显区别.与野生型小鼠、喂养10及20周的脂联素基因敲除小鼠相比,喂养30周的脂联素基因敲除小鼠出现了轻度的动脉钙化,其动脉的钙含量及ALP活性升高.通过对脂联素基因敲除小鼠进行外源性脂联素的补充,抑制了动脉钙化的出现及ALP活性升高. 结论在普通膳食喂养30周后,脂联素基因敲除小鼠出现轻度的动脉钙化,其机制可能与动脉中升高的ALP活性有关;外源性脂联素的补充可抑制脂联素基因敲除小鼠动脉钙化的发生,提示脂联素为动脉钙化的保护因子.  相似文献   

9.
目的研究海地瓜岩藻聚糖硫酸酯(fucoidan form Acaudina molpadioidea,Am-FUC)对胰岛素抵抗小鼠肝脏炎症反应的改善作用及机制。方法采用饲喂高脂高糖饲料法建立胰岛素抵抗小鼠模型,给予80mg/kg·bw的Am-FUC 19w。实验结束后,检测模型小鼠血清促炎症因子和抗炎症因子浓度和血清和肝脏FFA水平,用实时荧光定量PCR方法检测Am-FUC对肝脏组织炎症状因子基因m RNA表达,Western blotting法检测Am-FUC对胰岛素抵抗小鼠肝脏组织JNK和IKKβ/NFκB炎症通路的影响。结果 Am-FUC能显著地降低胰岛素抵抗小鼠血清促炎症因子浓度并增加抑炎症因子浓度(P0.01),降低血清和肝脏FFA浓度(P0.01),抑制抑炎症因子基因m RNA表达水平并促进抑炎症因子基因m RNA表达水平(P0.05,P0.01),抑制肝脏组织JNK1和IKKβ蛋白磷酸化(P0.05,P0.01)、增加细胞质中NFκB蛋白表达(P0.01),抑制细胞核中NFκB蛋白表达(P0.01)。结论 Am-FUC能通过抑制JNK和IKKβ/NFκB炎症通路起到改善胰岛素抵抗小鼠肝脏炎症反应的作用。  相似文献   

10.
目的探究过氧化物酶体增殖物激活受体(peroxisome proliferator-activated receptorα, PPARα)在高脂饲料诱导小鼠代谢综合征(metabolic syndrome, MS)发生发展过程中的作用与机制。方法选用129/Sv雄性健康的野生型(WT)和Ppara敲除型(KO)小鼠各10只,各自分为对照组和实验组。对照组小鼠食饲普通饲料(WT-Con/KO-Con),实验组小鼠食饲40%脂肪供能饲料(High-fat diet,HFD)(WT-HFD/KO-HFD),连续干预3月。实验结束前3 d对各组小鼠进行口服葡萄糖耐量试验;所有小鼠收集血清后处死,取附睾脂肪组织。检测血清中TC和TG的含量,分析脂肪组织的病理学变化以及炎症基因表达。结果 KO-HFD组小鼠体质量增加明显,且发生糖耐量损害,其血清TC和TG显著高于KO-Con组;且脂肪细胞体积明显大于KO-Con组,炎症基因mRNA的表达明显增加,且STAT3通路被激活;在WT两组小鼠中各指标均无明显差别。结论小鼠PPARα可对抗HFD诱导MS的发生与发展,该作用与STAT3炎症通路密切相关。[营养学报,2019,41(1):89-94]  相似文献   

11.
Animal studies using a high-fat diet (HFD) have studied the effects of lipid overconsumption by comparing a defined HFD either with a natural-ingredient chow diet or with a defined low-fat diet (LFD), despite the dramatic differences between these control diets. We hypothesized that these differences in the control diet could modify the conclusions regarding the effects that an increase of fat in the diet has on several metabolic parameters. For 11 weeks, C57bl6/J mice were fed a low-fat chow diet (8% energy from fat), a typical semisynthetic LFD (12%), or a semisynthetic HFD (sy-HF) (40%). Conclusions about the effect of sy-HF on body weight gain, subcutaneous adipose tissue, insulin sensitivity, and adipose tissue inflammation were modified according to the control LFD. Conversely, conclusions about epididymal and retroperitoneal adipose tissue; fat intake effects on liver and muscular lipids, cholesterol, free fatty acids, and markers of low-grade inflammation; and of adipose tissue macrophage infiltration were the same regardless of the use of low-fat chow diet or semisynthetic LFD. For some physiological outcomes, conflicting conclusions were even reached about the effects of increased fat intake according to the chosen low-fat control. Some deleterious effects of sy-HF may not be explained by lipid overconsumption but rather by the overall quality of ingredients in a semisynthetic diet. According to the control LFD chosen, conclusions on the lipid-related effects of HFDs must be formulated with great care because some end points are profoundly affected by the ingredient composition of the diet rather than by fat content.  相似文献   

12.
Immunoglobulin A (IgA) is a major antibody in the gut. We previously observed that a high-fat diet (HFD) reduces IgA reactivity to gut microbiota, but the physiological implications have yet to be elucidated. We hypothesized that a reduction of IgA reactivity to gut microbiota induced by a HFD may contribute to development of gut dysbiosis and inflammation that accompanies HFD feeding. To test our hypothesis, we used Aicda deficient mice, which have a deficiency in IgA production. Aicda deficient mice and wild-type mice were fed normal-fat diet or HFD for 12 weeks. We found that HFD feeding but not Aicda deficiency altered the fecal microbiota composition. Meanwhile, Aicda deficiency significantly increased gene expression of inflammatory cytokines in the ileum, but not in the colon despite no significant difference between diets. These results suggest that a reduction of IgA reactivity to gut microbiota induced by HFD partly contributes to development of inflammation in the ileum, but not to gut dysbiosis. We also found that the fasting blood insulin level was significantly increased by Aicda deficiency only under HFD feeding. Furthermore, the gene expression of monocyte chemoattractant protein1, a major chemokine responsible for the onset of hyperinsulinemia, in the liver was significantly increased by HFD feeding and tended to be increased by Aicda deficiency. These findings suggest that a reduction of IgA reactivity to gut microbiota induced by HFD contributes to hyperinsulinemia partly via increasing monocyte chemoattractant protein-1 expression in the liver.  相似文献   

13.
Hepatocyte apoptosis in addition to oxidative stress could be a key component in the pathogenesis of nonalcoholic steatohepatitis (NASH). However, the underlying mechanisms of hepatocellular apoptotic response associated with oxidative stress have not been investigated in high-fat diet (HFD)-induced NASH models. In this study, Sprague-Dawley rats were fed either a Lieber-DeCarli control diet (CD; 35% energy from fat) or a HFD (71% energy from fat) for 6 wk. Pathologic lesions, lipid peroxidation products, and apoptotic hepatocytes in the liver were examined. The expressions of hepatic tumor necrosis factor-alpha (TNFalpha) and protein concentrations of cleaved caspase-3, cytochrome p4502E1 (CYP2E1), phosphorylated c-Jun NH(2)-terminal kinase (JNK), Bax, Bcl-2, and Bcl-xl were measured. Results showed that the key histological features of NASH, including steatosis, inflammatory cell infiltration, and ballooning degeneration of hepatocytes, were induced by HFD feeding, with increased hepatic TNFalpha mRNA expression. HFD-fed rats had elevated lipid peroxidation products and CYP2E1 protein in the liver. The apoptotic hepatocytes were significantly greater in livers of rats fed HFD than in those fed CD, and these were associated with a higher level of cleaved caspase-3. In addition, HFD feeding increased both hepatic phosphorylated JNK and pro-apoptotic Bax but did not affect anti-apoptotic Bcl-2 and Bcl-xl compared with CD feeding. These data indicate that the increased oxidative stress and its associated JNK activation as well as an imbalance of pro- and anti-apoptotic proteins in the Bcl-2 family all contribute to high hepatocyte apoptosis that may play an important role in the pathogenesis of NASH in this model.  相似文献   

14.
BACKGROUND/OBJECTIVESEvidence indicates that berry anthocyanins are anti-atherogenic, antioxidant, and anti-inflammatory. However, berries differ vastly in their anthocyanin composition and thus potentially in their biological and metabolic effects. The present study compared hypolipidemic, antioxidant, and anti-inflammatory properties of blueberry (BB), blackberry (BK), and blackcurrant (BC) in a diet-induced obesity (DIO) mouse model.MATERIALS/METHODSMale C57BL/6J mice were fed a high fat (HF; 35% fat, w/w) control diet or a HF diet supplemented with freeze-dried 5% BB, 6.3% BK or 5.7% BC for 12 weeks (10 mice/group) to achieve the same total anthocyanin content in each diet. Plasma lipids, antioxidant status and pro-inflammatory cytokines were measured. The expression of genes involved in antioxidant defense, inflammation, and lipid metabolism was determined in the liver, epididymal adipose tissue, proximal intestine, and skeletal muscle. Histological analysis was performed to identify crown-like structure (CLS) in epididymal fat pads to determine macrophage infiltration.RESULTSNo differences were noted between the control and any berry-fed groups in plasma levels of liver enzymes, insulin, glucose, ferric reducing antioxidant power, superoxide dismutase, and tumor necrosis factor α. However, BK significantly lowered plasma triglyceride compared with the HF control and other berries, whereas BC significantly reduced F4/80 mRNA and the number of CLS in the epididymal fat pad, indicative of less macrophage infiltration.CONCLUSIONSThe present study provides evidence that BB, BK and BC with varying anthocyanin composition differentially affect plasma lipids and adipose macrophage infiltration in DIO mice, but with no differences in their antioxidant capacity and anti-inflammatory potential.  相似文献   

15.

Background

Increasing evidence suggests that diets high in polyunsaturated fatty acids (PUFA) confer health benefits by improving insulin sensitivity and lipid metabolism in liver, muscle and adipose tissue.

Methods

The present study investigates metabolic responses in two different lines of mice either selected for high body weight (DU6) leading to rapid obesity development, or selected for high treadmill performance (DUhTP) leading to a lean phenotype. At 29 days of age the mice were fed standard chow (7.2% fat, 25.7% protein), or a high-fat diet rich in n-3 PUFA (n-3 HFD, 27.7% fat, 19% protein) or a high-fat diet rich in n-6 PUFA (n-6 HFD, 27.7% fat, 18.6% protein) for 8 weeks. The aim of the study was to determine the effect of these PUFA-rich high-fat diets on the fatty acid profile and on the protein expression of key components of insulin signalling pathways.

Results

Plasma concentrations of leptin and insulin were higher in DU6 in comparison with DUhTP mice. The high-fat diets stimulated a strong increase in leptin levels and body fat only in DU6 mice. Muscle and liver fatty acid composition were clearly changed by dietary lipid composition. In both lines of mice n-3 HFD feeding significantly reduced the hepatic insulin receptor β protein concentration which may explain decreased insulin action in liver. In contrast, protein kinase C ζ expression increased strongly in abdominal fat of n-3 HFD fed DUhTP mice, indicating enhanced insulin sensitivity in adipose tissue.

Conclusions

A diet high in n-3 PUFA may facilitate a shift from fuel deposition in liver to fuel storage as fat in adipose tissue in mice. Tissue specific changes in insulin sensitivity may describe, at least in part, the health improving properties of dietary n-3 PUFA. However, important genotype-diet interactions may explain why such diets have little effect in some population groups.  相似文献   

16.

Background

Increased fat intake is associated with obesity and may make obese individuals uniquely susceptible to the effects of lipophilic aryl hydrocarbon receptor (AHR) ligands.

Objectives

We investigated the consequences of high-fat diet (HFD) and AHR ligands on body composition, mammary development, and hepatic P450 expression.

Methods

Pregnant C57BL/6J (B6) and DBA/2J (D2) dams, respectively expressing high- or low-responsive AHR, were dosed at mid-gestation with TCDD. At parturition, mice were placed on an HFD or a low-fat diet (LFD). Body fat of progeny was measured before dosing with 7,12-dimethylbenz[a]anthracene (DMBA). Fasting blood glucose was measured, and liver and mammary glands were analyzed.

Results

Maternal TCDD exposure resulted in reduced litter size in D2 mice and, on HFD, reduced postpartum survival in B6 mice. In D2 mice, HFD increased body mass and fat in off-spring, induced precocious mammary gland development, and increased AHR expression compared with mice given an LFD. Maternal TCDD exposure increased hepatic Cyp1a1 and Cyp1b1 expression in offspring on both diets, but DMBA depressed Cyp1b1 expression only in mice fed an HFD. In D2 progeny, TCDD exposure decreased mammary terminal end bud size, and DMBA exposure decreased the number of terminal end buds. Only in D2 progeny fed HFD did perinatal TCDD increase blood glucose and the size of mammary fat pads, while decreasing both branch elongation and the number of terminal end buds.

Conclusions

We conclude that despite having a low-responsive AHR, D2 progeny fed a diet similar to that consumed by most people are susceptible to TCDD and DMBA exposure effects blood glucose levels, mammary differentiation, and hepatic Cyp1 expression.  相似文献   

17.
An increased risk of iron deficiency has been reported in obese individuals. We investigated hepatic iron status and serum levels of both adipokines and inflammatory markers in obese mice to test the hypothesis that high-fat-diet (HFD)–induced obesity leads to reduced iron storage associated with inflammation. Four-week-old C57BL mice were fed a HFD containing 60% energy from fat for 16 weeks and were compared with mice on a control diet with 10% energy from fat. The HFD group had significantly higher levels of leptin (43.7 ng/mL in control, n = 16 vs 104.3 ng/mL in HFD, n = 17; P < .001) and significantly lower amounts of high-molecular-weight adiponectin (4.80 μg/mL in control, n = 16 vs 3.67 μg/mL in HFD, n = 18; P = .002) compared with the control group. Higher serum amyloid A levels in the HFD group (60.4 μg/mL in control, n = 17 vs 117.9 μg/mL in HFD, n = 18; P < .001) suggest inflammation in the HFD-induced obese animals. The HFD group had lower hepatic nonheme iron (3.12 μg/mg protein in control, n = 17 vs 0.869 μg/mg protein in HFD, n = 16; P < .001). Expression of hepcidin messenger RNA (mRNA) was only 54% of the control levels in HFD mice (P = .016). However, the ratio of hepcidin mRNA expression to nonheme iron was 2.5-fold higher in the HFD compared with the control animals. Hepcidin is a homeostatic regulator of iron metabolism that restricts intestinal iron absorption and is also known as a mediator of inflammation. Increased serum amyloid A levels and a higher ratio of hepatic hepcidin mRNA expression to nonheme iron suggest that lower hepatic iron status in obese animals might be associated with inflammation.  相似文献   

18.
目的探讨浓缩乳清蛋白粉对高脂饮食诱导肥胖小鼠肠道胆固醇代谢的影响。方法40只C57BL/6J小鼠随机分为对照、高脂饲料(HFD)、12.5%乳清蛋白(WP)和25%WP组,干预组在HFD中添加相应含量WP,喂养12w后测定各组小鼠的血脂水平、游离脂肪酸、空腹血糖和胰岛素,并计算胰岛素抵抗指数(HOMA-IR)。取小肠组织,Western blot法测定胆固醇吸收相关的Niemann-Pick C1-Like 1(NPC1L1)、清道夫受体B1(SR-B1)、以及胆固醇外流相关的肝X受体α(LXRα)及ATP结合盒转运子G1(ABCG1)蛋白的表达水平。结果与HFD组比,25%WP组小鼠血清总胆固醇、空腹胰岛素和HOMA-IR值显著下降;12.5%和25%WP组小鼠的血清低密度脂蛋白胆固醇水平亦显著下降。与HFD组比,25%WP组小鼠的小肠组织中NPC1L1、SR-B1蛋白表达显著下调,而LXRα和ABCG1蛋白表达显著上调。结论乳清蛋白可能通过减少肠道胆固醇吸收,增加肠道胆固醇外流,改善了高脂饮食引起的糖脂代谢紊乱。  相似文献   

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