运动对血清脂联素水平影响的研究现状

脂联素是脂肪细胞分泌的一种细胞因子,具有增强脂肪酸的氧化、提高肌肉葡萄糖摄取、改善胰岛素抵抗、抗动脉粥样硬化、抗炎等作用,通过PPARα和AMPK信号通路发挥作用。脂联素在健康人体血清中含量丰富,在肥胖及2型糖尿病患者中含量降低。运动对脂联素水平影响未取得一致的研究结果,寻找一个有效干预脂联素水平的运动处方是一个值得关注的问题。     

河南蜂胶对血糖的调节作用研究

[目的]研究河南蜂胶调节血糖的功能作用。[方法]将糖尿病造模成功的小鼠随机分为模型组、阳性对照组和高、中、低3个蜂胶剂量组;另取一组为正常对照组,观察河南蜂胶对正常小鼠及糖尿病小鼠空腹血糖的调节作用。[结果]与糖尿病模型组相比,蜂胶能明显降低糖尿病小鼠的空腹血糖水平,对正常小鼠血糖没有影响。[结论]河南蜂胶具有降血糖的功能作用。     

不同剂量STZ与高脂饲料联合诱导糖尿病小鼠模型

探讨不同剂量链脲霉素(streptozotocin,STZ)联合高脂膳食建立2型糖尿病小鼠模型的效果。选择C57BL/6J小鼠,5周龄开始饲喂高脂饲料,持续10周,将膳食诱导的肥胖(dietinduced obesity,DIO)小鼠随机分为对照组及3个试验组[分别为试验组A(腹腔注射STZ 50mg/kg)、B(腹腔注射STZ 70mg/kg)、C(腹腔注射STZ 100mg/kg)],每组均为10只动物。试验组小鼠腹腔注射STZ后与对照组一起继续饲喂高脂2周。分别检测各组小鼠造模前后空腹血糖,胰岛素水平及成模后糖耐量。结果表明试验A、B、C 3组的成模率分别为70%、90%、100%,其血糖含量(分别为229.4±8.72、349.4±6.71、432.5±11.0 mg/dL)显著地高于对照组(168.7±4.18mg/dL);其血浆胰岛素含量(分别为1.83±0.288,0.659±0.058,0.438±0.023ng/mL)明显低于对照组(2.95±0.218ng/mL)。不同STZ剂量可诱导不同程度的糖尿病症状。     

猪成熟脂肪细胞产生的胰岛素抵抗与应激

 猪脂肪细胞内环境的稳定在脂类代谢过程中起着重要作用。在肥胖等疾病发生过程中,成熟脂肪细胞面临由于能量过剩、炎性反应等造成的内质网应激,导致由于脂肪细胞负荷过重而致内环境稳定的破坏,从而产生胰岛素抵抗。本文就近年来关于猪脂肪细胞应激导致胰岛素抵抗的最新研究进展进行综述,为了解成熟脂肪细胞应激与胰岛素抵抗产生的机制提供参考。     

松花苦桑粉对糖尿病小鼠降血糖的作用

[目的]研究松花苦桑粉的降血糖作用,为其作为辅助降血糖的功能食品提供科学依据。[方法]以正常小鼠、四氧嘧啶(ALX)诱导的糖尿病模型小鼠为材料,按体重随机分组,灌胃给药,测定空腹血糖,进行淀粉负荷糖耐量试验(OSTT)。[结果]松花苦桑粉以13.6、6.6、3.3 g/kg 3种剂量灌胃15 d,以13.6 g/kg剂量效果为好,具有统计学意义(P<0.01)。松花苦桑粉以13.6、6.6、3.3 g/kg 3种剂量灌胃35 d,其中13.6 g/kg剂量组ALX性糖尿病小鼠空腹血糖显著降低(P<0.05);高、中和低剂量组均明显降低ALX性糖尿病小鼠血糖水平。[结论]在空腹血糖试验,松花苦桑粉降低正常小鼠空腹血糖试验结果阳性,降低ALX性糖尿病小鼠空腹血糖试验结果阳性。在糖耐量试验,松花苦桑粉对ALX性糖尿病小鼠的糖耐量试验结果阳性。13.6、6.6和3.3 g/kg松花苦桑粉对ALX性糖尿病小鼠的糖耐量试验结果阳性。     

小米糠膳食纤维调节血糖和血脂功能的研究

以小米糠膳食纤维为原料,通过测定空腹血糖、糖耐量、血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)等指标,研究了小米糠膳食纤维对血糖和血脂的调节作用,结果表明,与对照组比较,低、中剂量组空腹血糖值差异极显著(P＜0.01),高剂量组差异显著(P＜0.05);低剂量组在0、0.5、2h时的血糖值和曲线下面积均低于模型对照组,且差异显著(P＜0.05);中剂量组能显著降低血清总胆固醇水平(P＜0.05);各剂量组对甘油三酯和高密度脂蛋白胆固醇的含量影响不大.     

Function of GATA transcription factors in preadipocyte-adipocyte transition

Genes that control the early stages of adipogenesis remain largely unknown. Here, we show that murine GATA-2 and GATA-3 are specifically expressed in white adipocyte precursors and that their down-regulation sets the stage for terminal differentiation. Constitutive GATA-2 and GATA-3 expression suppressed adipocyte differentiation and trapped cells at the preadipocyte stage. This effect is mediated, at least in part, through the direct suppression of peroxisome proliferator-activated receptor gamma. GATA-3-deficient embryonic stem cells exhibit an enhanced capacity to differentiate into adipocytes, and defective GATA-2 and GATA-3 expression is associated with obesity. Thus, GATA-2 and GATA-3 regulate adipocyte differentiation through molecular control of the preadipocyte-adipocyte transition.     

Disulfide-dependent multimeric assembly of resistin family hormones

Resistin, founding member of the resistin-like molecule (RELM) hormone family, is secreted selectively from adipocytes and induces liver-specific antagonism of insulin action, thus providing a potential molecular link between obesity and diabetes. Crystal structures of resistin and RELMbeta reveal an unusual multimeric structure. Each protomer comprises a carboxy-terminal disulfide-rich beta-sandwich "head" domain and an amino-terminal alpha-helical "tail" segment. The alpha-helical segments associate to form three-stranded coiled coils, and surface-exposed interchain disulfide linkages mediate the formation of tail-to-tail hexamers. Analysis of serum samples shows that resistin circulates in two distinct assembly states, likely corresponding to hexamers and trimers. Infusion of a resistin mutant, lacking the intertrimer disulfide bonds, in pancreatic-insulin clamp studies reveals substantially more potent effects on hepatic insulin sensitivity than those observed with wild-type resistin. This result suggests that processing of the intertrimer disulfide bonds may reflect an obligatory step toward activation.     

Diabetes, obesity, and the brain

Recent evidence suggests a key role for the brain in the control of both body fat content and glucose metabolism. Neuronal systems that regulate energy intake, energy expenditure, and endogenous glucose production sense and respond to input from hormonal and nutrient-related signals that convey information regarding both body energy stores and current energy availability. In response to this input, adaptive changes occur that promote energy homeostasis and the maintenance of blood glucose levels in the normal range. Defects in this control system are implicated in the link between obesity and type 2 diabetes.     

蜂胶桑叶复合片对2型糖尿病病人糖脂代谢的调节作用

[目的]研究蜂胶桑叶复合片对2型糖尿病患者血糖及血脂的影响。[方法]采用自身对照及组间对照法,选择符合试验条件的2型糖尿病患者,连续试食蜂胶桑叶复合片35 d后,测定空腹血糖、餐后2 h血糖、尿糖、胆固醇、甘油三酯及高密度脂蛋白胆固醇。[结果]试食35 d后试验组病人口渴多饮、多食易饥、倦怠乏力等糖尿病临床症状明显改善,症状积分极显著降低(P<0.01),试验组病人空腹血糖、餐后2 h血糖、胆固醇、甘油三酯含量较对照组及自身试食前均极显著降低(P<0.01);与试验前比较,试验组病人尿糖含量极显著降低(P<0.01);与对照组比较,高密度脂蛋白胆固醇、尿糖含量无显著变化(P>0.05)。试食期间未见明显不良反应。[结论]蜂胶桑叶复合片具有明显的辅助调节2型糖尿病病人糖脂代谢功能。     

Severely impaired adipsin expression in genetic and acquired obesity

Adipsin, a serine protease homolog, is synthesized and secreted by adipose cells and is found in the bloodstream. The expression of adipsin messenger RNA (mRNA) and protein was analyzed in rodents during metabolic perturbations and in several experimental models of obesity. Adipsin mRNA abundance is increased in adipose tissue during fasting in normal rats and in diabetes due to streptozotocin-induced insulin deficiency. Adipsin mRNA abundance decreased during the continuous infusion of glucose, which induces a hyperglycemic, hyperinsulinemic state that is accompanied by an increased adipose mass; it is suppressed (greater than 100-fold) in two strains of genetically obese mice (db/db and ob/ob), compared to their congenic counterparts, and is also reduced when obesity is induced chemically by injection of monosodium glutamate into newborn mice. Circulating adipsin protein is decreased in these animal models of obesity, as determined by immunoblotting with antisera to adipsin. Little change in adipsin expression is observed in a model of obesity obtained by pure overfeeding of normal rats (cafeteria model). These data suggest a possible role for adipsin in the above-mentioned disordered metabolic states, and raise the possibility that adipsin expression may be used to distinguish obesities that arise from certain genetic or metabolic defects from those that result from pure overfeeding.     

The gut and energy balance: visceral allies in the obesity wars

In addition to digesting and assimilating nutrients, the intestine and associated visceral organs play a key sensing and signaling role in the physiology of energy homeostasis. The gut, the pancreatic islets of Langerhans, elements in the portal vasculature, and even visceral adipose tissue communicate with the controllers of energy balance in the brain by means of neural and endocrine pathways. Signals reflecting energy stores, recent nutritional state, and other parameters are integrated in the central nervous system, particularly in the hypothalamus, to coordinate energy intake and expenditure. Our understanding of regulatory neural circuits and the signaling molecules that influence them has progressed rapidly, particularly after the discovery of the adipocyte hormone leptin. These discoveries have led to exploration of novel routes for obesity control, some of which involve gut-derived pathways.     

脂连素及其相关疾病

脂连素是近年发现的主要由脂肪细胞分泌的一种内源性生物活性多肽或蛋白质, 是脂肪细胞因子家族的重要新成员。作为一种胰岛素超敏化激素,其对调节人和动物胰岛素敏 感组织中葡萄糖和脂类的代谢起重要作用。     

新型降血糖中药方剂对STZ诱导小鼠糖尿病的影响

为获得糖尿病治疗的中药方剂,探讨由葛根、丹参、枳椇子组成的中药方剂对小鼠的抗糖尿病效应及潜在机制。利用链脲佐霉素(STZ)建立糖尿病模型,以空腹血糖大于11mmol/L为建模成功。30只小鼠分为空白组(健康小鼠)、试验组(糖尿病小鼠)和阴性对照组(糖尿病小鼠),每天对试验组进行中药方剂水煎服给药,空白组和阴性对照组每天灌服同等剂量蒸馏水,对小鼠的肝脏和肾脏生理指标变化进行检测。结果表明:STZ诱导的糖尿病小鼠给予葛根、丹参及枳椇子中药方剂灌服7d,试验组与阴性对照组相比,其空腹血糖降低,体重回升,肝脏指标白蛋白(ALB)下降31.58%,碱性磷酸酶(ALP)下降57.43%,谷丙转氨酶(ALT)回升87.80%,谷草转氨酶(AST)下降51.72%,总蛋白(TP)下降31.94%。由葛根、丹参和枳椇子组成的中药方剂在浓度为1g/L时对糖尿病小鼠有显著的治疗效果。     

肥胖对非致死性肺炎小鼠血液生理指标、4种细胞因子和免疫器官指数的影响

为探讨肥胖对非致死性肺炎全身性免疫反应的影响,将高脂诱导的肥胖小鼠分为Ⅰ、Ⅱ组,非肥胖小鼠分为Ⅲ、Ⅳ组,Ⅰ、Ⅲ组滴鼻40 μL含4×10⁹ cfu大肠埃希菌菌液,Ⅱ、Ⅳ组滴鼻40 μL生理盐水,于感染后2、6、12、24、48、72、96 h检测各组小鼠免疫器官指数、血液生理指标、血清细胞因子。结果显示,高脂饲喂8周,Ⅱ组体质量,血液WBC、GRA、MID数量,血清TNF-α、IL-6、IL-10、抵抗素浓度均显著高于Ⅳ组,脾质量及指数、胸腺质量及指数显著低于Ⅳ组(P<0.05)。感染后,Ⅰ组脾指数2~72 h显著高于Ⅱ组,2、6、48、72、96 h显著高于Ⅲ组(P<0.05),胸腺指数6、12 h显著低于Ⅱ组,72、96 h显著低于Ⅲ组(P<0.05)。Ⅰ、Ⅲ组血液WBC、GRA、MID在感染后先升高后降低最后恢复至对照组水平,24 h时显著低于对照组(P<0.05)。试验期间Ⅰ组WBC、GRA、MID均显著高于Ⅲ组(P<0.05)。感染后,Ⅰ、Ⅲ组血清TNF-α、IL-6、IL-10和抵抗素浓度于2 h显著升高(P<0.05),除Ⅲ组抵抗素外,均维持高浓度至48 h,Ⅰ组4种细胞因子2 h和6 h显著高于Ⅲ组,96 h显著低于Ⅲ组(P<0.05)。表明高脂饮食诱导的肥胖对全身性炎症反应的敏感性提高,增强了免疫反应。     

不同工艺提取的蜂胶对2型糖尿病大鼠降血糖作用比较

探讨了采用乙醇提取和超临界萃取的2种蜂胶的降血糖作用,并进行比较研究.将大鼠随机分组后连续9周灌喂蜂胶,每2周测空腹血糖和餐后血糖;于第9周进行糖耐量试验;处死大鼠后,测定其血液中甘油三脂、胆固醇、尿酸、肌酐、尿素氮的含量;解剖大鼠后分别称取其肝、肾重量.结果表明造模后试验组的终重与正常组的差异显著;超临界试验组的糖耐量和胆固醇指标与模型1组的差异显著;其他各项指标的差异均不显著.     

高脂肪饮食诱导糖尿病小鼠模型

[目的]探讨以高脂肪纯化饲料诱导的遗传背景和环境因素共同起作用的C57BL/6J小鼠用于糖尿病药物早期筛选的最短诱导周期.[方法]雄性4周龄C57BL/6J小鼠20只适应性喂养7d后随机分为2组,同时饲喂高脂肪饲料.葡萄糖耐受性试验（OGTT）中1组C57BL/6J小鼠口服生理盐水（对照组）,另1组口服磷酸西他列汀（阳性药组）.喂养期间对禁食后血糖（FBG）和体重（BW）进行连续监测,同时进行OGTT试验并监测血浆胰岛素（PINS）水平.[结果]高脂喂养1周后小鼠体重升高迅速,并表现为中心型肥胖.第4周FBG和PINS较前3周显著性升高,2周OGTT给糖15 min阳性药组血浆胰岛素水平较对照组有显著性升高.[结论]仅饲喂高脂饲料4周的C57BL/6J可用于糖尿病药物药效试验的筛选.该模型方法简单易行,周期短,稳定性好,与人类自然发病过程相似,是较为理想的降血糖药物筛选模型.     

PPAR-γ基因对脂质代谢调控机制的生物信息学分析

过氧化物酶体增殖激活受体γ(PPAR-γ)是具有重要生物学功能的转录因子,可调控脂肪细胞分泌的多种蛋白质因子基因的表达,促进脂肪细胞分化。它与肥胖、Ⅱ型糖尿病、心血管疾病、癌症的发病风险相关联。研究基于TRANSFAC数据库信息,利用MEME/MAST方法对PPAR-γ进行全基因组范围的靶基因生物信息学定位,并对获得的靶基因进行了GO和KEGG分析,探讨PPAR-γ基因对脂质代谢影响的分子机理。结果表明,PPAR-γ靶基因显著富集于36个GO节点(P<0.05),并参与了10个KEGG代谢通路(P<0.05),这其中大部分GO节点和KEGG代谢通路与脂质代谢密切相关。研究有助于理解PPAR-γ基因对脂质代谢影响的分子机理;同时,对于肥胖和糖尿病等复杂疾病的诊断、预防和治疗具有积极意义。     

中医经络按摩对糖尿病前期患者的作用效果

目的 探讨中医经络按摩对糖尿病前期患者代谢指标、人体成分及疾病转归的影响。方法 将36例糖尿病前期患者采用随机数字表法随机分为试验组和对照组各18例,两组均统一接受饮食、运动教育课,试验组实施经络按摩干预3个月,对照组统一授课进行生活方式健康教育,促使行为改变,比较两组3个月前后糖化血红蛋白、空腹血糖、餐后2 h血糖、血脂等代谢指标、人体成分及疾病转归情况。结果 干预3个月后,与对照组相比,试验组空腹血糖、餐后2 h血糖、糖化血红蛋白降低,差异有统计学意义（P<0.05,P<0.01）,与干预前相比,试验组患者BMI、体脂、内脂降低,差异有统计学意义（P<0.05,P<0.01）,对照组与试验前相比,低密度脂蛋白升高,差异有统计学意义（P<0.05）。对照组（18例）3个月后16例处于糖尿病前期、2例糖尿病患者,试验组（16例）3个月后9例处于糖尿病前期、7例处于正常状态、2例脱落,两组比较差异有统计学意义（P=0.001）。结论 中医经络按摩可改善糖尿病前期患者的血糖控制情况,降低其转变为糖尿病的风险,延缓糖尿病的发生、发展。     

广西巴马小型猪PPARγ-2基因多态性与2型糖尿病易感性的相关性

[目的]探讨PPARγ-2基因多态性与广西巴马小型猪2型糖尿病易感性的关系。[方法]利用高糖高脂日粮饲喂24头广西巴马小型猪,利用PCR方法扩增PPARγ-2基因外显子2部分序列,测定其空腹血糖和胰岛素(INS)含量并进行糖耐量试验。[结果]克隆的PPARγ-2基因外显子2部分序列存在1处SNP位点(19813A/G),有AG(7头)和AA(17头)2种基因型。AG型广西巴马小型猪的空腹胰岛素含量和糖耐量试验中60 min血糖值显著高于AA型(P0.05),而AG型广西巴马小型猪2型糖尿病发生率(71.4%)明显高于AA型(5.9%)。[结论]广西巴马小型猪PPARγ-2基因外显子2的19813A/G多态性与2型糖尿病易感性有关。