Objective To explore the impact of high-fat diet on bone marrow-originated endothelial progenitor cells(EPCs),oxidative stress and glutathione peroxidase-1 (GPx-1) expression in rats.Methods 23 male Wistar rats were randomly divided into normal control group (NC goup,n=13) and high-fat fed group (HF group,n=10).Rats in NC group were fed with a standard lab diet,and rats in HF group were fed with a high-fat diet (502 kcal/100 g).Lee's index,body weight were measured to evaluate whether the obese rat model was established at 16 weeks after feeding.Blood samples were collected via carotid arterial cannula.Serum insulin,lipids and oxidative stress index were measured.Perirenal and epididymis adipose tissues were obtained and weighed.EPCs were detached,cultivated and evaluated by multi-wave laser confocal microscopy.Protein and gene expressions of GPx-1 were determined by Western blot and reverse transcription real time polymerase chain reaction(RT real-time PCR).Results After 16 weeks of high-fat diet,the body weight,Lee's index and visceral adipose tissue were increased in HF group as compared with NC group [(465.11 ±27.69) gvs.(404.38±17.01) g,(312.08±9.82) vs.(297.74±8.75),(20.07±1.94) g vs.(5.31±1.11) g,all P＜0.001].The levels of fasting blood glucose,cholesterol,triglyceride were increased in HE group as compared with NC group[(5.85±0.77) mmol/L vs.(4.285±0.74)mmol/L,(1.35±0.21) mmol/L vs.(0.95±0.14) mmol/L,(1.02±0.21) mmol/L vs.(0.65±0.19)mmol/L,all P＜0.01].The levels of fasting insulin(FIns)and HOMA-IR were higher in HF group than in NCgroup [(3.46±0.77) mmol/L vs.(2.04±0.51) mmol/L,(0.90±0.24) vs.(0.40±0.19),both P＜0.001].Levels of serum glutathion peroxidase(GSH-Px)and erythrocuprein SOD,and total anti-oxidative capacity were decreased in HF group as compared with NC group [(759.13 ±60.71) mU/L vs.(826.26±65.83) mU/L,(72.76±5.41)mU/L vs.(80.44±7.91) mU/L,(5.18±0.35) mU/L vs.(6.01±0.93) mU/L,all P＜0.05].Malonaldehyde (MDA) level was increased,EPCs count and protein and mRNA expressions of GPx-1 were decreased in HF group as compared withNC group [(6.09±0.96) mol/L vs.(5.14±0.89) μmol/L,(62.55 ± 4.85) vs.(71.19±5.95),(0.50±0.13) vs.(1.29±0.42),(0.50±0.13) vs.(1.29±0.42),all P＜0.05 or 0.01].Multiple linear regression analysis showed that MDA was an influential factor for EPCs,Lee's index was an influential factor for GSH-Px,total cholesterol (TC) was an influential factor for TAO-C and SOD,and FINs was an influential factor for MDA.Conclusions High-fat diet can induce obesity and insulin resistance,increase the visceral adiposity,decrease the quantity of EPCs and protein and mRNA expressions of GPx-1 in rats.Oxidative stress is one of influential factors for the decrease of EPCs quantity in high fat diet induced obese rats.%目的 探讨高脂饮食对大鼠骨髓源内皮祖细胞(EPCs)数量、氧化应激水平的影响及EPCs谷胱甘肽过氧化物酶-1(GPx-1)的表达,分析高脂饮食是否通过诱导氧化应激影响EPCs的数量及功能. 方法 清洁级健康雄性Wistar大鼠23只,随机分为正常对照组13只,高脂饮食组(高脂组)10只.对照组给予基础饲料,总热量为348 kcal/100 g;高脂组喂以高脂饲料,总热量为502kca1/100 g.16周后测定Lee's指数、体质量,判断造模是否成功.造模成功后空腹颈动脉插管抽血,分离血清,测定胰岛素、血脂、氧化应激等指标.留取肾周、附睾周围脂肪,称质量.分离并培养EPCs,10d后多波长激光共聚焦显微镜鉴定EPCs,并测定EPCs GPx-1的mRNA表达及蛋白表达.结果 16周后,高脂组与对照组比较,体质量分别为(465.1±27.7)g比(404.4±17.0)g,Lee's指数312.1±9.8比297.7±8.8,腹腔内脂肪含量(20.1±1.9)g比(15.3±1.1)g,均增加(均P＜0.001);空腹血糖(5.85±0.77) mmol/L比(4.29±0.74) mmol/L,胆固醇(1.35±0.21) mmol/L比(0.95±0.14)mmol/L,三酰甘油(1.02±0.21) mmol/L比(0.65±0.19) mmol/L,均升高(均P＜0.01);空腹胰岛素(3.46±0.77)mmol/L比(2.04±0.51) mmol/L与胰岛素抵抗指数0.90±0.24比0.40±0.19,升高(P＜0.001);超氧化物歧化酶(SOD) (72.8±5.4) mU/L比(80.4±7.9) mU/L,谷胱甘肽过氧化物酶(GSH-Px) (759.1±60.7) mU/L比(826.3±65.8) mU/L,总抗氧化能力(TAO-C)(5.18±0.35) mU/L比(6.01±0.93) mU/L,均降低(均P＜0.05);丙二醛水平升高[(6.09±o.96) μmol/L比(5.14±0.89)μmol/L] (P＜0.05);EPCs数量减少(62.55±4.85比71.19±5.95,P＜0.001),GPx-1 mRNA表达(0.50±0.13比1.29±0.42)及GPx-1蛋白表达(0.50±0.13比1.29±0.42)均下降(P＜0.05和P＜0.01).多元直线回归分析显示,丙二醛是EPCs的影响因素;Lee's指数是GSH-Px的影响因素;总胆固醇是TAO-C及SOD的影响因素;空腹胰岛素是丙二醛的影响因素. 结论 高脂喂养可导致大鼠肥胖,内脏脂肪增加,胰岛素抵抗和EPCs数量减少,EPCs GPx-1 mRNA表达及蛋白表达均下降,氧化应激是肥胖大鼠EPCs数量减少影响因素之一.
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