长期睡眠剥夺下调AMPK/SIRT1/PGC-1α通路引起小鼠脂代谢紊乱

目的探讨长期睡眠剥夺对小鼠肝组织腺苷酸激活蛋白激酶(adenosine 5’-monophosphateactivated protein kinase,AMPK)/沉默信息调节因子1(silent information regulation1,SIRT1)/过氧化物酶体增殖物激活受体γ共激活因子-1α(peroxisome proliferator-activated receptorγcoactivator 1α,PGC-1α)系统的影响。方法2月龄C57BL/6J小鼠16只随机分为睡眠剥夺组和正常对照组,睡眠剥夺组利用睡眠剥夺仪每天剥夺睡眠20 h,每周剥夺6 d,连续10周。正常对照组在相同实验条件下自由睡眠10周。每周测量一次体重,10周后进行小鼠体成分测定,并采集血液、肝脏和脂肪组织样本,检测血清褪黑素水平、肝组织AMPKα、SIRT1、PGC-1α及胆固醇调节元件结合蛋白1C(sterol regulatory element-binding protein 1C,SREBP-1C)蛋白表达水平,以及脂肪组织中脂肪合成关键酶脂肪酸合成酶(fatty acid synthase,FAS)、乙酰辅酶A羧化酶1(acetyl CoA carbosylase 1,ACC1)表达水平。结果建模结束后,睡眠剥夺组小鼠体重显著高于对照组(F=10.955,P=0.006),且从第6周末开始,睡眠剥夺组小鼠体重明显高于对照组(F=8.535,P=0.012),并且睡眠剥夺组小鼠体脂量[(14.58±1.70)%]高于对照组[(11.24±1.64)%](t=4.007,P=0.001),血清褪黑素浓度[(2.33±0.53)ng/ml]低于对照组[(2.87±0.23)ng/ml](t=2.643,P=0.019),AMPK通路中的AMPKα(t=7.134,P<0.001)、SIRT1(t=7.531,P<0.001)、PGC-1α(t=11.537,P<0.001)表达水平降低,AMPK/SIRT1/PGC-1α通路下调。而SREBP-1C表达水平升高,差异有统计学意义(t=-4.496,P=0.001)。同时睡眠剥夺小鼠脂肪组织中FAS(t=-4.375,P=0.001)、ACC1表达水平均升高(t=-4.072,P=0.001)。结论长期睡眠剥夺可致褪黑素受体介导的AMPK/SIRT1/PGC-1α通路抑制,并且脂肪合成相关基因表达增强,引起能量代谢特别是脂代谢稳态失调和体脂增加。     

Resveratrol attenuates steatosis in obese Zucker rats by decreasing fatty acid availability and reducing oxidative stress

Non-alcoholic fatty liver disease (NAFLD) is one of the most common manifestations of chronic liver disease worldwide. The aim of the present study was to assess the effect of resveratrol on liver fat accumulation, as well as on the activity of those enzymes involved in lipogenesis and fatty acid oxidation in fa/fa Zucker rats. A total of thirty rats were assigned to three experimental groups and orally treated with resveratrol for 6 weeks, or without resveratrol (C: control group; RSV15 group: 15?mg/kg body weight per d; RSV45 group: 45?mg/kg body weight per d). Liver histological analysis was performed by microscopy. Levels of hepatic carnitine palmitoyltransferase-Ia (CPT-Ia), acyl-coenzyme A oxidase (ACO), fatty acid synthase, glucose-6-phosphate dehydrogenase and malic enzyme were assessed by spectrophotometry, and acetyl-CoA carboxylase was assessed by radiometry. Commercial kits were used to determine serum TAG, NEFA, total HDL and non-HDL-cholesterol, glycerol, ketonic bodies, glucose, insulin, adiponectin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP), hepatic TAG, thiobarbituric acid reactive substrates, GSH (GSSG) and superoxide dismutase. Resveratrol reduced liver weight and TAG content. It did not modify the activity of lipogenic enzymes but it did increase CPT-Ia and ACO activities. NEFA and ALP were reduced in both resveratrol-treated groups. AST/GOT was reduced only by the lowest dose. ALT/GPT, TAG and adiponectin remained unchanged. Resveratrol reduced liver oxidative stress. This study demonstrates that resveratrol can protect the liver from NAFLD by reducing fatty acid availability. Moreover, resveratrol also protects liver from oxidative stress.     

Naringin induces skeletal muscle fiber type transformation via AMPK/PGC-1α signaling pathway in mice and C2C12 myotubes

A large number of studies have shown that polyphenols can regulate skeletal muscle fiber type transformation through AMPK signal. However, the effects and mechanism of naringin (a natural polyphenol) on muscle fiber type transformation still remains unclear. Thus, we hypothesized that naringin would induce the transformation of skeletal muscle fibers from type II to type I by AMPK signaling. C2C12 myotubes and BALB/c mice models were used to test this hypothesis. We found that naringin significantly increased the protein expression of slow myosin heavy chain (MyHC), myoglobin and troponin I type I slow skeletal (Troponin I-SS) and the activities of succinate dehydrogenase (SDH) and malate dehydrogenase (MDH), and significantly decreased fast MyHC protein expression and lactate dehydrogenase (LDH) activity, accompanied by the activation of AMPK and the activity of peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α) in mice and C2C12 myotubes. Further inhibition of AMPK activity by compound C showed that the above effects were significantly inhibited in C2C12 myotubes. In conclusion, naringin promotes the transformation of skeletal muscle fibers from type II to type I through AMPK/PGC-1α signaling pathway, which not only enriches the nutritional and physiological functions of naringin, but also provides a theoretical basis for the regulation of muscle fiber type transformation by nutritional approaches.     

Feeding oxidized fat during pregnancy up-regulates expression of PPARα-responsive genes in the liver of rat fetuses

Background

Feeding oxidized fats causes activation of peroxisome proliferator-activated receptor α (PPARα) in the liver of rats. However, whether feeding oxidized fat during pregnancy also results in activation of PPARα in fetal liver is unknown. Thus, this study aimed to explore whether feeding oxidized fat during pregnancy causes a PPARα response in fetal liver. Two experiments with pregnant rats which were administered three different diets (control; oxidized fat; clofibrate as positive control) in a controlled feeding regimen during either late pregnancy (first experiment) or whole pregnancy (second experiment) were performed.

Results

In both experiments pregnant rats treated with oxidized fat or clofibrate had higher relative mRNA concentrations of the PPARα-responsive genes acyl-CoA oxidase (ACO), cytochrome P₄₅₀ 4A1 (CYP4A1), L-type carnitin-palmitoyl transferase I (L-CPT I), medium-chain acyl-CoA dehydrogenase (MCAD), and long-chain acyl-CoA dehydrogenase (LCAD) in the liver than control rats (P < 0.05). In addition, in both experiments fetuses of the oxidized fat group and the clofibrate group also had markedly higher relative mRNA concentrations of ACO, CYP4A1, CPT I, MCAD, and LCAD in the liver than those of the control group (P < 0.05), whereas the relative mRNA concentrations of PPARα, SREBP-1c, and FAS did not differ between treatment groups. In the second experiment treatment with oxidized fat also reduced triacylglycerol concentrations in the livers of pregnant rats and fetuses (P < 0.05).

Conclusion

The present study demonstrates for the first time that components of oxidized fat with PPARα activating potential are able to induce a PPARα response in the liver of fetuses. Moreover, the present study shows that feeding oxidized fat during whole pregnancy, but not during late pregnancy, lowers triacylglycerol concentrations in fetal livers.     

沙棘提取物对猪脂肪中部分脂肪代谢相关基因表达的影响

目的研究早期断奶仔猪喂饲沙棘提取物对脂肪组织中部分脂肪代谢相关基因表达的影响及其机制。方法选用(28±2)日龄东北民猪16头,随机分为对照组和试验组。试验组仔猪饲料中添加沙棘提取物(1000mg/kg),喂饲28d后改成基础饲粮,D180屠宰取样,RT-PCR方法检测猪脂肪组织中过氧化物酶增殖剂激活受体α(PPARα)、γ(PPARγ)、乙酰辅酶A氧化酶(ACO)和脂肪酸合成酶(FAS)的基因表达。结果早期喂饲沙棘提取物可使(1)腹脂和皮脂中PPARα和ACO的mRNA表达均增加;(2)腹脂中PPARγmRNA表达降低,腹脂和皮脂中FASmRNA表达均降低。结论断奶仔猪早期喂饲沙棘提取物可在转录水平调控脂肪代谢相关基因的表达,这可能是减少猪体内脂肪沉积和改善猪肉品质的机制之一。     

Aerobic exercise's reversal of insulin resistance by activating AMPKα-ACC-CPT1 signaling in the skeletal muscle of C57BL/6 mice

Insulin resistance (IR) is a common pathophysiological feature of Type 2 diabetes. Although the mechanisms leading to IR are still elusive, evidence has shown that aerobic exercise can reverse this process. To investigate the effects of aerobic exercise on IR, the authors created an IR animal model by feeding C57BL/6 mice a high-fat diet for 8 wk. They then compared the effect of 6 wk of treadmill training (60 min/d) at 75% VO2max on mice in normal-diet (NE) and high-fat-diet (HE) groups with their sedentary control groups. Levels of skeletal-muscle AMPKα (AMP-activated protein kinase α), ACC (acetyl-CoA carboxylases), and CPT1 (carnitine palmitoyltransferase 1) mRNA and AMPKα, pAMPK-Thr172, ACC, pACC-Ser79, and CPT1 protein expressions were analyzed. In addition, fasting serum levels of insulin, triglyceride, and cholesterol were measured. The results demonstrate that 6 wk of exercise increased AMPKα mRNA expression by 11% and 25 % (p<.01) in the NE and HE groups, respectively, and AMPKα protein expression by 37.9% and 20.1% (p<.01) in NE and HE compared with their sedentary control. In addition, ACC mRNA and protein expressions declined, whereas CPT1 mRNA and protein expressions were elevated in both exercise groups compared with sedentary control groups. In addition, pAMPK-Thr172 and pACC-Ser79 expression increased significantly in the NE and HE groups compared with sedentary control groups. In conclusion, our results demonstrate that 6 wk of aerobic exercise can effectively ameliorate IR by increasing the expression of AMPKα and pAMPK-Thr172, thereby activating the key enzymes that facilitate lipid metabolism.     

Effect of dietary seal and fish oils on triacylglycerol metabolism in rats

Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were distributed mainly in the sn-1 and 3 positions of seal oil triacylglycerol and in the sn-2 position of fish oil triacylglycerol. Seal oil or fish oil-rich fats having constant polyunsaturated/monounsaturated/saturated fatty acids and n-6/n-3 polyunsaturated fatty acid (PUFA) ratios were fed to rats for 3 wk. Control rats were fed on a fat containing linoleic acid as the sole PUFA. Seal oil more effectively lowered serum and liver triacylglycerol concentrations than fish oil. The activities of fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH) and hepatic triacylglycerol lipase (HTGL) were significantly lower in the seal oil group than in the control group, whereas the activity of HTGL was significantly lower and the hepatic peroxisomal beta-oxidation and activity of lipoprotein lipase (LPL) in adipose tissue were significantly higher in the fish oil group than in the control group. These observations suggest that the predominant hypotriacylglycerolemic effect of seal oil is caused by the suppression of fatty acid synthesis.     

From clock genes to telomeres in the regulation of the healthspan

Biological clocks are classified into oscillatory (clock genes) and unidirectional hourglass clocks (telomeres). Clock genes align behavioral and biochemical processes with the day/night cycle. Telomeres, the repeated series of DNA sequences that cap the ends of chromosomes, become shorter during cell division. Shortened telomeres have been documented in various pathological states associated with aging. Human activity is driven by NADH and ATP produced from nutrients, and the resulting NAD and AMP play a predominant role in energy regulation. Caloric restriction increases both AMP and NAD and is known to extend the healthspan (healthy lifespan) of animals. Silent information regulator T1 (SIRT1), the NAD-dependent deacetylase, attenuates telomere shortening, while peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a master modulator of gene expression, is phosphorylated by AMP kinase and deacetylated by SIRT1. Thus, PGC-1α is a key component of the circadian oscillator that integrates the mammalian clock and energy metabolism. Reactive oxygen species produced in clock mutants result in telomere shortening. The circadian rhythms produced by clock genes and lifestyle factors are ultimately controlled by the human brain and drive homeostatic and hedonic feeding and daily activity.     

Berberine Improves Cognitive Deficiency and Muscular Dysfunction via Activation of the AMPK/SIRT1/PGC-1a Pathway in Skeletal Muscle from Naturally Aging Rats

Objective

The manifestations of aging include cognitive deficits and muscular dysfunction, which are closely linked to impairment of mitochondrial biogenesis. Berberine, an isoquinoline alkaloid, presents multiple anti-diabetic pharmacological effects. Evidence has indicated that insulin resistance and cognitive impairment share the same pathogenesis, and berberine could reverse glucose metabolism abnormalities and muscle mitochondrial dysfunction induced by a high-fat diet. This study was used to investigate whether berberine could be used as an anti-aging drug to prevent cognitive deficits and muscular dysfunction in natural aging.

Methods

Biochemical indicators and an intraperitoneal glucose tolerance test were tested in 5-monthold rats (5 mo group), 24-month-old rats (24 mo group) and 24-month-old rats that had undergone 6 months of berberine treatment (BBR group). A Morris water maze test was conducted to assess the cognitive ability of the rats. Insulin resistance in whole-body was evaluated by intraperitoneal glucose tolerance test (IPGTT). The morphology of the skeletal muscle tissue was observed by hematoxylin-eosin (HE) staining. The levels of total cholesterol, triglyceride, ATP and reactive oxygen species (ROS) were assessed with corresponding reagent kits. The protein expressions of GLUT4, AMPK, SIRT1 and PGC-1α in skeletal muscle were examined by Western blot.

Results

The results showed that administration of berberine for 6 months significantly improved cognitive deficits and insulin resistance in naturally aging rats (p<0.01). Furthermore, berberine treatment helped normalize the disordered alignment and the decreased number of muscle fibers (p<0.01) in the skeletal muscle of 24 mo rats. Berberine decreased the levels of ROS in both the serum and the skeletal muscle of 24 mo rats (p<0.01). Berberine increased the protein expression of p-AMPK, SIRT1 and PGC-1α and increased the production of ATP in the skeletal muscle of aging rats (p<0.01).

Conclusions

Berberine markedly ameliorates aging-related reductions in cognitive ability and muscular function, and the activation of the AMPK/SIRT1/PGC-1α pathway in skeletal muscle may be the underlying protective mechanism of berberine on muscular function.

     

Purple sweet potato anthocyanins attenuate hepatic lipid accumulation through activating adenosine monophosphate–activated protein kinase in human HepG2 cells and obese mice

Purple sweet potato is a functional food rich in anthocyanins that possess disease-preventive properties. Anthocyanins are known to possess potent antidiabetic properties. However, the effect of the anthocyanin fraction (AF) from purple sweet potato on hepatic lipid metabolism remains unclear. Our hypothesis is that AF inhibits hepatic lipid accumulation through the activation of adenosine monophosphate–activated protein kinase (AMPK) signaling pathways in vitro and in vivo. In this study, we evaluated body weight, liver histology, and hepatic lipid content in high-fat diet (HFD)–fed ICR mice treated with AF. In addition, we characterized the underlying mechanism of AF's effects in HepG2 hepatocytes through Western blot analysis. Anthocyanin fraction (200 mg/kg per day) reduced weight gain and hepatic triglyceride accumulation and improved serum lipid parameters in mice fed an HFD for 4 weeks. Anthocyanin fraction significantly increased the phosphorylation of AMPK and acetyl-coenzyme A carboxylase (ACC) in the liver and HepG2 hepatocytes. In addition, AF down-regulated the levels of sterol regulatory element-binding protein 1 and its target genes including ACC and fatty acid synthase (FAS). The specific AMPK inhibitor compound C attenuated the effects of AF on the expression of lipid metabolism–related proteins such as SREBP-1 and FAS in HepG2 hepatocytes. The beneficial effects of AF on HFD-induced hepatic lipid accumulation are thus mediated through AMPK signaling pathways, suggesting a potential target for the prevention of obesity.     

辛伐他汀和非诺贝特对小鼠肝脏载脂蛋白M表达的影响及调控机制

目的 探讨辛伐他汀和非诺贝特及两者联合对小鼠肝脏载脂蛋白M（apoM）表达的影响及其机制,为防治动脉粥样硬化提供依据.方法 32只C57BL/6N小鼠按数字表法分为四组,对照组：普通饮食喂养;他汀组：辛伐他汀[10 mg/（kg·d）]干预;贝特组：非诺贝特[100 mg/（kg·d）]干预;联合组：辛伐他汀[10 mg/（kg·d）]和非诺贝特[100 mg/（kg·d）]干预,4周后分别检测小鼠肝脏apoM mRNA和蛋白、肝细胞核因子-1α（HNF-1α）mRNA、肝X受体-α（LXRα）mRNA的表达.结果 辛伐他汀和非诺贝特均上调apoM mRNA（1.97±0.04;2.02±0.02）和蛋白、HNF-1α mRNA（1.74±0.05;1.71±0.04）的表达,联合组（3.07±0.03;2.57±0.03）升高程度高于他汀组（1.97±0.04;1.74±0.05）和贝特组（2.02±0.02;1.71±0.04）（P＜0.05）.辛伐他汀下调LXRα mRNA（1.00±0.02）表达（P＜0.05）,非诺贝特上调LXRα mRNA（2.80±0.04）表达（P＜0.05）,联合组LXRα mRNA表达（1.56±0.03）与对照组（1.53±0.03）比较差异无统计学意义（P＞0.05）.结论 辛伐他汀和非诺贝特可上调apoM表达,两者联合疗效更显著;其机制可能与两者调控HNF-1α和LXRα有关.     

利用寡核苷酸微阵列芯片分析ERRα过度表达对子宫内膜癌HEC-1A细胞转录因子活性的影响

目的:讨论过度表达雌激素受体相关受体(ERRα)对子宫内膜癌细胞HEC-1A中不同转录因子转录活性的影响。方法:构建带有绿色荧光蛋白和G418耐药基因筛选标记的真核表达质粒pEGFP-N1-3FLAG-ERRα,将质粒转染子宫内膜癌细胞株HEC-1A,荧光显微镜下检测并通过G418高浓度筛选、低浓度维持建立ERRα稳定高表达的子宫内膜癌细胞株HEC-1A/ERRα。分别抽提子宫内膜癌细胞HEC-1A、转染质粒空载体的HEC-1A/空载体细胞,ERRα过度表达的HEC-1A/ERRα细胞的核蛋白。将核蛋白与CY3、CY5双色标记的326检测信号通道的转录因子芯片(寡核苷酸微阵列芯片)杂交并通过双色共聚焦激光扫描仪分析。结果:转染ERRα真核表达质粒后,与HEC-1A细胞和转染载体的HEC-1A/空载体细胞对比,子宫内膜癌细胞HEC-1A/ERRα中ERRα的mRNA和蛋白表达明显增加。HEC-1A-ERRα细胞株与HEC-1A/空载体细胞株转录因子活性比较显示7个转录位点的活性发生显著改变,其中调控SREBP,AP-1,c-Myc,Usf-1/2转录因子的结合位点活性下调,而调控RFX-1,PPAR-α,PPAR-γ的转录因子的结合位点活性上调。而在HEC-1A/空载体细胞株和HEC-1A细胞株中未检出上述7种转录因子的差异表达。结论:①寡核苷酸微阵列芯片是一种有效的筛选转录因子的工具;②ERRα过度表达下调子宫内膜癌细胞HEC-1A中转录因子SREBP,AP-1,c-Myc,Usf-1/2的转录活性,上调RFX,PPARα,PPARγ的转录活性。     

High-fat diet inhibits PGC-1α suppressive effect on NFκB signaling in hepatocytes

Purpose

The peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) regulates the expression of genes implicated in fatty acid oxidation and oxidative phosphorylation. Its role in liver steatosis is well established, since mice with liver-specific deletion of PGC-1α exhibit lipid accumulation and high-fat diet reduces hepatic PGC-1α expression in mice. In this study, we investigated the role of PGC-1α in the inflammatory changes observed in steatohepatitis induced by high-fat diet.

Methods

C57black/6 mice were fed a high-fat diet containing 30% fat for 10 weeks. After euthanasia, liver morphology was examined by HE staining and inflammation was determined by IL-6, TNF-α, and IL-1β quantification. Liver gene expression of PGC-1 isoforms was evaluated by real-time PCR and p65 NFκB nuclear translocation by Western blotting. HepG2 cells were treated with linoleic acid overload for 72 h to create an in vitro model of steatohepatitis. RNA interference (RNAi) was used to evaluate the involvement of PGC-1α on inflammatory mediators’ production by hepatocytes.

Results

The high-fat diet led to a state of nonalcoholic steatohepatitis, associated with increased deposits of intra-abdominal fat, hyperglycemia and hyperlipidemia. Mice liver also exhibited increased proinflammatory cytokines’ levels, decreased PGC-1α expression, and marked increase in p65 NFκB nuclear translocation. Linoleic acid treated cells also presented increased expression of proinflammatory cytokines and decreased PGC-1α expression. The knockdown of PGC-1α content caused an increase in IL-6 expression and release via enhanced IκBα phosphorylation and subsequent increase of p65 NFκB nuclear translocation.

Conclusion

High-fat diet induces liver inflammation by inhibiting PGC-1α expression and its suppressive effect in NFκB pathway.

     

胆固醇影响大鼠脂肪代谢的机制研究

目的:研究胆固醇影响大鼠脂肪代谢的机制。方法:以添加1%胆固醇的AIN76合成饲料喂食Wistar大鼠4w,对照组不添加胆固醇。分别测血清甘油三酯(TG)、总胆固醇(TC)、磷脂(PL)、高密度脂蛋白(HDL-C)、血糖、游离脂肪酸(NEFA)浓度;测肝脏TG、TC、PL浓度以及苹果酸酶(ME)、葡萄糖6磷酸脱氢酶(G6PDH)、脂肪酸合成酶(FAS)、磷脂酸磷酸酶(PAP)和肉毒碱棕榈酰转移酶(CPT)活性、酰基辅酶A-胆固醇酰基转移酶(ACAT)、胆固醇7a-羟化酶(CYP7A)和羟甲基戊二酸单酰辅酶A还原酶(HMG-CoA reductase)mRNA。结果:胆固醇显著增加大鼠血液TC和非HDL-C浓度、降低HDL-C和TG浓度,使肝脏TC和TG浓度分别提高了20和4倍。胆固醇组大鼠肝脏ME活性降低40%、G6PDH活性降低70%、FAS活性降低50%,PAP活性降低15%,CPT的活性降低25%,肝脏FAS的mRNA量降低35%,CPT1和CPT2的mRNA量分别降低30%和50%。HMG-CoA还原酶mRNA量降低25%,而CYP7A和ACAT mRNA量分别增加了6.5和1.6倍。结论:高胆固醇饮食引起肝脏TG蓄积,但并不增加肝脏TG合成相关酶的活性和基因表达。     

The role of dietary protein in hepatic lipogenesis in the young rat

1. The effect of varying dietary levels of casein (40-140 g/kg) on hepatic lipogenesis and the levels of hepatic fatty acid synthetase (FAS), glucose-6-phosphate dehydrogenase (EC 1.1.1.49; G6PD), malic enzyme (EC 1.1.1.40; ME), citrate cleavage enzyme (EC 4.1.3.8; CCE), acetyl CoA carboxylase (EC 6.4.1.2; AcCx), glucokinase (EC 2.7.1.2; GK), and pyruvate dehydrogenase (PDH) was examined in young, growing rats. 2. The activities of AcCx, FAS, G6PD and in vivo fatty acid synthesis were generally found to increase with increased dietary protein. 3. The levels of GK and PDH were not related to dietary protein. 4. ME decreased with increasing dietary protein. 5. The results demonstrate a dissociation between hepatic fatty acid synthesis and ME and suggest that when rats consume low-protein diets the NADPH needed for fatty acid synthesis is generated primarily by ME but that as the level of dietary protein is increased the contribution of ME is reduced while that of the phosphogluconate pathway becomes more important.     

Pan-PPAR agonist beneficial effects in overweight mice fed a high-fat high-sucrose diet

ObjectiveWe analyzed the effect of peroxisome proliferator-activated receptor (PPAR) agonists on adipose tissue morphology, adiponectin expression, and its relation to glucose and insulin levels in C57BL/6 mice fed a high-fat high-sucrose (HFHS) diet.MethodsMale C57BL/6 mice received one of five diets: standard chow, HFHS chow, or HFHS plus rosiglitazone (PPAR-γ agonist), fenofibrate (PPAR-α agonist), or bezafibrate (pan-PPAR agonist). Diets were administered for 11 wk and medications from week 6 to week 11. Glucose intolerance (GI) and insulin resistance were evaluated by oral glucose tolerance testing and homeostasis model assessment for insulin resistance, respectively. Adipocyte diameter was analyzed in epididymal, inguinal, and retroperitoneal fat pads and by adiponectin immunostain.ResultsMice fed the HFHS chow had hyperglycemia, GI, insulin resistance, increased fat pad weight, adipocyte hypertrophy, and decreased adiponectin immunostaining. Rosiglitazone improved GI, insulin sensitiveness, and adiponectin immunostaining, but it resulted in body weight gain, hyperphagia, and adipocyte and heart hypertrophy. Fenofibrate improved all parameters except for fasting glucose and GI. Bezafibrate was the most efficient in decreasing body weight and glucose intolerance.ConclusionActivation of PPAR-α, -δ, and -γ together is better than the activation of PPAR-α or -γ alone, because bezafibrate showed a wider range of action on metabolic, morphologic, and biometric alterations due to an HFHS diet in mice.