MAPK8基因在小鼠源性3T3-Ll脂肪细胞诱导分化中表达水平的变化

[目的]观察小鼠源性3T3-L1脂肪前体细胞诱导分化过程中MAPK8基因表达水平的变化,探讨MAPK8基因与肥胖发生之间的关系.[方法]体外培养3T3-L1前体脂肪细胞,在诱导3T3-L1脂肪细胞分化成熟的不同时段,采用RT-PCR技术检测脂肪细胞中MAPK8基因的mRNA表达水平.[结果]MAPK8基因高表达于3T3-L1脂肪前体细胞中,随细胞分化成熟该基因表达水平逐渐下调.MAPK8基因表达水平除在诱导分化前至第4 d、第2～5 d、第6～10 d时段内差异无显著性外,其余各时段间差异均有显著性(P＜0.05).[结论]MAPK8基因与肥胖发生有关,在3T3-L1细胞分化过程中表达逐渐下调可能有利于脂肪细胞的分化成熟和脂质积聚.     

芦丁抑制3T3-L1前脂肪细胞分化并促进米色脂肪细胞形成

  目的  探讨芦丁对米色脂肪细胞形成的影响。  方法  用不同浓度芦丁处理3T3-L1前脂肪细胞;细胞计数盒（CCK8）检测不同浓度芦丁对细胞活性影响,油红O染色观察脂滴大小;Western blot检测过氧化物酶增殖物激活受体 – γ（PPAR-γ）、aP2及解偶联蛋白1（UCP1）表达;RT-qPCR检测UCP1、PRDM16、Dio2表达;细胞免疫荧光检测线粒体变化。  结果  芦丁在0～250 μmol/L范围内对细胞活性无明显影响,且以药物依赖性方式减少脂滴生成;与对照组[aP2（1.12 ± 0.03）]、[PPAR-γ（0.87 ± 0.02）]比较,50、100、250 μmol/L芦丁使aP2[分别为（0.87 ± 0.03）、（0.64 ± 0.01）、（0.64 ± 0.05）]、PPAR-γ[分别为（0.73 ± 0.02）、（0.46 ± 0.02）、（0.43 ± 0.05）]蛋白表达降低,使UCP1蛋白表达[分别为（0.58 ± 0.03）、（0.42 ± 0.02）、（0.34 ± 0.01）]增加;与对照组比较,50 μmol/L芦丁可使UCP1、PRDM16、Dio2表达[分别为（7.02 ± 0.24）、（2.09 ± 0.06）、（10.40 ± 0.93）]升高;细胞免疫荧光显示,3T3-L1前脂肪细胞内线粒体含量增加。  结论  芦丁可减少3T3-L1前脂肪细胞脂滴生成,并促进米色脂肪细胞形成。     

血管紧张素Ⅱ对前脂肪细胞分化相关转录因子表达的影响

目的探讨血管紧张素Ⅱ(angiotensin Ⅱ,AngⅡ)对前脂肪细胞分化过程中转录因子PPARγ、C/EBPα、SREBP1-c/ADD-1表达的调节从而研究AngⅡ调节前脂肪细胞分化可能的分子机制。方法 3T3-L1前脂肪细胞体外传代培养及诱导分化,用RT-PCR技术检测诱导分化过程中不同浓度AngⅡ处理6d对前脂肪细胞分化相关转录因子PPARγ、C/EBPα、SREBP1-c/ADD-1 mRNA表达水平的影响。结果 RT-PCR结果显示,100 nmol/L的AngⅡ处理细胞6 d后,PPARγ、C/EBPα、SREBP1-c/ADD-1 mRNA的相对表达量与对照组(AngⅡ添加浓度为0 nmol/L)有显著性差异(P<0.05),比对照组相应的转录因子分别增加了48%、50%、43%。结论前脂肪细胞分化过程中AngII能够上调PPARγ、C/EBPα、SREBP1-c/ADD-1 mRNA的表达量,AngⅡ可能通过影响PPARγ、C/EBPα和SREBP1-c/ADD-1的表达来调节前脂肪细胞的分化过程。     

TSG-6基因在3T3-L1脂肪细胞诱导分化中表达水平的变化

[目的] 探讨TSG-6基因在3T3-L1脂肪细胞诱导分化中表达水平的变化。[方法] 采用细胞培养和RT-PCR技术，检测细胞诱导分化不同时段脂肪细胞中TSG-6基因的表达水平。[结果] ①随着脂肪细胞逐渐分化成熟，TSG-6基因mRNA表达水平逐渐升高；②TSG-6基因表达水平除在细胞分化第0-2d、第3-5d和第7-10d各时段内差异无显著性(P＞0.05)外，其余各时段之间表达水平差异均有显著性(P＜0.05)。[结论] TSG-6基因与细胞分化以及脂原形成可能相关。     

脂肪细胞分化过程中脂联素受体的时序性表达(英文)

目的探讨SW872前脂肪细胞分化过程中脂联素受体基因表达的时序性变化。方法体外培养,0.6mM油酸诱导SW872前脂肪细胞分化24h,48h,72h,油红0染色观察细胞内脂肪的聚积;RT-PCR方法检测不同分化时间点脂联素受体1及脂联素受体2 mRNA水平。结果0.6mM油酸诱导分化72h,能成功地将SW872前脂肪细胞分化为成熟的脂肪细胞。SW872前脂肪细胞表达两种脂联素受体,诱导分化刺激24h,脂联素受体1 mRNA水平是诱导分化前的1.95倍,脂联素受体2 mRNA水平是诱导分化前的1.61倍;诱导分化刺激48h,脂联素受体1 mRNA水平是诱导分化前的2.16倍,脂联素受体2 mRNA水平是诱导分化前的2.34倍;诱导分化72h,脂联素受体1 mRNA水平是诱导分化前的2.54倍,脂联素受体2 mRNA水平是诱导分化前的4.09倍。结论SW872脂肪细胞表达脂联素两种受体增殖,且两种脂联素受体的基因表达呈分化相关性。     

LYRM1基因绿色荧光蛋白融合载体的构建及表达

[目的]构建LYRM1基因绿色荧光蛋白融合载体,进而观察LYRM1基因编码蛋白在细胞内的定位情况.[方法]运用RT-PCR技术从人网膜脂肪组织中分离LYRM1基因的完整编码框,将其亚克隆到绿色荧光蛋白表达载体pEGFP-N2,脂质体转染3T3-L1前体脂肪细胞,激光共聚焦显微镜下观察融合蛋白的表达情况.[结果]PCR、酶切鉴定及测序结果表明重组质粒构建正确.激光共聚焦显微镜下观察到pEGFP-N2转染的细胞中绿色荧光均匀分布于整个细胞,而pEGFP-LYRM1转染的细胞中绿色荧光主要集中在细胞核区域.[结论]成功构建了LYRM1绿色荧光蛋白融合载体,LYRM1编码蛋白在细胞中定位于胞核中.     

体脂和肥胖相关基因多态性与生活行为因素交互作用对学龄儿童肥胖的影响

目的 探讨体脂和肥胖相关基因(FTO)多态性与生活行为因素的交互作用对学龄儿童肥胖的影响.方法 从"北京市儿童青少年代谢综合征(BCAMS)研究"中选取6～18岁学龄儿童3503名,分为肥胖组(1229名)和非肥胖组(2274名).进行问卷调查、静脉采血和基因型检测.结果 采用因子分析方法,共提取蛋白类食物、果蔬、烟酒、静态生活方式和业余体育活动5个公因子.logistic回归分析显示,以FTO基因与蛋白类食物交互作用为例,当两因素共同存在时,其中归因于交互作用的危险度占19.16%.该位点多态性与果蔬、静态生活方式和业余体育活动的交互作用归因百分比则依次为5.97%、19.62%和12.43%;该位点与烟酒可能不存在交互作用.结论 在中国学龄儿童中,蛋白类食物、果蔬、静态生活方式和业余体育活动等生活行为因素可能修饰FTO基因与肥胖的关系.但仍需要大规模、前瞻性的干预性研究,验证FTO基因与环境因素的交互作用对儿童肥胖的真实影响.     

体脂和肥胖相关基因多态性与生活行为因素交互作用对学龄儿童肥胖的影响

目的 探讨体脂和肥胖相关基因(FTO)多态性与生活行为因素的交互作用对学龄儿童肥胖的影响.方法 从"北京市儿童青少年代谢综合征(BCAMS)研究"中选取6～18岁学龄儿童3503名,分为肥胖组(1229名)和非肥胖组(2274名).进行问卷调查、静脉采血和基因型检测.结果 采用因子分析方法,共提取蛋白类食物、果蔬、烟酒、静态生活方式和业余体育活动5个公因子.logistic回归分析显示,以FTO基因与蛋白类食物交互作用为例,当两因素共同存在时,其中归因于交互作用的危险度占19.16%.该位点多态性与果蔬、静态生活方式和业余体育活动的交互作用归因百分比则依次为5.97%、19.62%和12.43%;该位点与烟酒可能不存在交互作用.结论 在中国学龄儿童中,蛋白类食物、果蔬、静态生活方式和业余体育活动等生活行为因素可能修饰FTO基因与肥胖的关系.但仍需要大规模、前瞻性的干预性研究,验证FTO基因与环境因素的交互作用对儿童肥胖的真实影响.     

体脂和肥胖相关基因多态性与生活行为因素交互作用对学龄儿童肥胖的影响

目的 探讨体脂和肥胖相关基因(FTO)多态性与生活行为因素的交互作用对学龄儿童肥胖的影响.方法 从"北京市儿童青少年代谢综合征(BCAMS)研究"中选取6～18岁学龄儿童3503名,分为肥胖组(1229名)和非肥胖组(2274名).进行问卷调查、静脉采血和基因型检测.结果 采用因子分析方法,共提取蛋白类食物、果蔬、烟酒、静态生活方式和业余体育活动5个公因子.logistic回归分析显示,以FTO基因与蛋白类食物交互作用为例,当两因素共同存在时,其中归因于交互作用的危险度占19.16%.该位点多态性与果蔬、静态生活方式和业余体育活动的交互作用归因百分比则依次为5.97%、19.62%和12.43%;该位点与烟酒可能不存在交互作用.结论 在中国学龄儿童中,蛋白类食物、果蔬、静态生活方式和业余体育活动等生活行为因素可能修饰FTO基因与肥胖的关系.但仍需要大规模、前瞻性的干预性研究,验证FTO基因与环境因素的交互作用对儿童肥胖的真实影响.     

Lipin基因：肥胖及脂肪营养不良的新靶标

已知npin基因缺乏造成脂肪营养不良，动物实验研究显示，它可促进肥胖。Lipin表达的轻微变异，可能影响人的肥胖程度。因为Lipin的外周表达，可能成为肥胖或脂肪营养不良的治疗目标。     

Pref-1, a preadipocyte secreted factor that inhibits adipogenesis

Preadipocyte factor 1 (Pref-1) belongs to the Notch/Delta/Serrate family of epidermal growth factor-like repeat-containing proteins. Pref-1 is highly expressed in 3T3-L1 cells but is extinguished during adipocyte differentiation. Pref-1 serves as an excellent marker for preadipocytes. Furthermore, Pref-1 is an inhibitor of adipogenesis. Constitutive expression of Pref-1 inhibits, whereas antisense Pref-1 enhances, 3T3-L1 adipocyte differentiation. We found that Pref-1 is synthesized as a transmembrane protein but processed to generate soluble forms, including a large 50-kDa soluble form and the small soluble forms. Furthermore, only the large soluble form, but not the small soluble or the transmembrane forms of Pref-1, is biologically active to inhibit adipogenesis. We recently elucidated that the 50-kDa soluble form of Pref-1 is released by an ADAM family member, tumor necrosis factor-alpha converting enzyme (ADMA 17). In vivo, mice lacking Pref-1 show accelerated fat deposition; conversely, mice overexpressing soluble Pref-1 in adipose tissue show a decrease in fat mass, reduced expression of adipocyte markers, and lower adipocyte-secreted factors. These findings clearly demonstrate the inhibitory effect of Pref-1 on adipogenesis in vivo.     

人谷胱甘肽硫转移酶M1基因在CHO细胞中的表达

目的　构建人谷胱甘肽硫转移酶M1(GSTM1)的CHO细胞表达体系。方法　重组质粒pcDNA3 1 GSTM1用LipofectamineTM2 0 0 0转染CHO细胞 ,用G418筛选细胞的阳性克隆 ,并用PCR、RT PCR和Westernblot进行鉴定 ,测定GSTM1酶活性。结果　GSTM1基因已转染到CHO细胞的基因组 ,并转录表达 ,生成GSTM1蛋白 ,经测定活性达到2 8mmol/ (min·mgprot)。结论　通过CHO GSTM1细胞表达 ,为基因工程生产具有完整功能GSTM1的进一步纯化提供了材料 ,为研究化学致癌物在真核细胞中的代谢 ,作为遗传药理学、毒理学研究的候选细胞株奠定了基础。     

Decreased thermic effect of a mixed meal during overnutrition in human obesity

Short-term mixed calorie overfeeding increases basal energy expenditure in man but its effects on the thermic effect of a meal (TEM) are unclear. The thermogenic and hormonal responses to an 800-kcal liquid mixed meal were measured in six lean and six obese subjects during weight maintenance, during 18 d of overfeeding 1000 kcal/d, and during 18 d of a 589 kcal/d diet (obese subjects only). There was no change in the TEM in lean subjects between weight maintenance and overfeeding. In the obese group the TEM was lower during both overfeeding (p less than 0.05) and underfeeding (p less than 0.05) compared with weight maintenance. Overfeeding increased rates of net postprandial glucose oxidation and decreased lipid oxidation in the lean subjects only. Alterations in glucose oxidation rates and the insulin response to meals may contribute to an impaired TEM in human obesity during overnutrition.     

ENPP1 gene, insulin resistance and related clinical outcomes

PURPOSE OF REVIEW: Insulin resistance plays a significant role in both morbidity and mortality of the general population. Understanding the molecular mechanisms of insulin resistance would help the identification of at-risk individuals in the presymptomatic stage, and the discovery of novel and more effective treatments. The transmembrane glycoprotein ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1) inhibits insulin receptor signalling and has recently emerged as a key player in the development of insulin resistance. This review will summarize data available on the relationship between ENPP1 and insulin resistance. RECENT FINDINGS: Overexpression of ENPP1 in insulin target tissues is an early, intrinsic defect observed in human insulin resistance. A missense ENPP1 single nucleotide polymorphism, K121Q, has been recently described with the Q121 variant being a stronger inhibitor than K121 of insulin receptor function. In addition, the Q121 variant has been repeatedly associated with insulin resistance and related abnormalities including body weight changes, type 2 diabetes and macrovascular complications, thus suggesting a pleiotropic role of the ENPP1 gene on several metabolic abnormalities. SUMMARY: A deep understanding of ENPP1 mode of action and the mechanisms regulating its expression and function are likely to provide new tools for early identification and treatments of patients at risk for the devastating clinical outcomes related to insulin resistance.     

A novel MYT1L mutation in a boy with syndromic obesity: Case report and literature review

BackgroundPathogenic variants involving the MYT1L gene lead to an autosomal dominant form of syndromic obesity, characterized by polyphagia, intellectual disability/developmental delay, and behavioral problems, and that a characteristic facial phenotype does not seem to be recognizable.MethodsTrio whole exome sequencing was performed in a 10-year-old Brazilian male presenting polyphagia, severe early-onset obesity, intellectual disability, speech delay, macrocephaly, frontal bossing, telecanthus, strabismus, and hypogenitalism. Additionally, we performed a literature review of patients carrying non-copy number MYT1L variants.ResultsA de novo genetic variant not previously reported in MYT1L (NM_015025.4:c.2990C > A) was identified in the proband and classified as pathogenic. From a literature search, 22 further patients carrying non-copy number MYT1L variants were identified, evidencing that although the associated phenotype is quite variable, intellectual disability/developmental and speech delays are always present. Further, most patients have obesity or overweight due to polyphagia. Macrocephaly, strabismus, behavioral problems, and hand/feet malformations are also recurrent features.ConclusionsWe described the first Brazilian case of MYT1L related syndrome and highlighted clinical characteristics based on the literature. Other syndromic forms of obesity such as Prader-Willi, Bardet-Biedl, Börjeson-Forssman-Lehmann, MORM, Cohen, Alstrom, and Kleefstra type 1 syndromes should be considered in the differential diagnosis. Further, although obesity is frequent, it is not an obligatory feature of all carriers of MYT1L mutations.     

The relationship between obesity and health related quality of life of women in a Turkish city with a high prevalence of obesity

The purpose of this study was to demonstrate the relationship between body weight and HRQOL in a representative sample of nonpregnant women in reproductive age period. The data of this cross-sectional study was extracted from a survey: Manisa Demographic and Health Survey (MDHS) conducted in Manisa city in 2000. The study population of MDHS is a representative sample of 1602 reproductive (15-49) age women. World Health Organization Quality of Life Questionnaire abbreviated version (WHOQOL-BREF), which was composed of four domain factors (physical, psychological, social relations and the environment), was used to assess HRQOL. Each of four domains had a possible score ranged between 0 (poor HRQOL) and 20 (excellent HRQOL). The mean age of the women was 35.29+/- 8.19 years. Among them, 35.8 % had normal weight (BMI 18.5 to 24.9), 32.3 % were overweight (BMI 25.0 to 29.9) while 31.9 % were moderate and 3.4% were morbidly obese. After adjusting for age, level of education and co-morbid illnesses, subjects with a BMI higher than normal value, had significantly lower HRQOL scores, compared to normal-weight individuals on each of the domains, except for the environmental domain. Our results suggested that the body weight alone could negatively affect HRQOL. In other words, obesity not only increased the risk of morbidity and mortality, but also affected the perceived health and life quality negatively. In conclusion, in addition to age, socioeconomic status and co-morbid illnesses, body weight should also be controlled in studies examining HRQOL.