Toward a unified theory of caloric restriction and longevity regulation

The diet known as calorie restriction (CR) is the most reproducible way to extend the lifespan of mammals. Many of the early hypotheses to explain this effect were based on it being a passive alteration in metabolism. Yet, recent data from yeast, worms, flies, and mammals support the idea that CR is not simply a passive effect but an active, highly conserved stress response that evolved early in life's history to increase an organism's chance of surviving adversity. This perspective updates the evidence for and against the various hypotheses of CR, and concludes that many of them can be synthesized into a single, unifying hypothesis. This has important implications for how we might develop novel medicines that can harness these newly discovered innate mechanisms of disease resistance and survival.     

内脏脂肪素（Visfatin）的特性及与妊娠的关系

成人病胎儿起源学说是目前在国内外被普遍关注的话题，新发现的脂肪细胞因子Visfatin与IUGR密切相关，导致IUGR的病理状况引起母体循环血中Visfatin水平升高，高水平的Visfatin有可能是后来发展成为胰岛素抵抗和Ⅱ型糖尿病的早期的标记。     

针刺八髎穴联合荷芪散治疗多囊卵巢综合征患者的临床效果

目的 观察针刺八髎穴联合荷芪散在多囊卵巢综合征患者中的应用效果.方法 选取2018年6月至2019年11月达州市中西医结合医院收治的200例多囊卵巢综合征患者作为研究对象.根据随机数字表法将其分为观察组和对照组,每组100例.对照组在常规治疗基础上采用针灸疗法直刺八髎穴,观察组在对照组基础上联合荷芪散治疗.观察并比较两...     

脂肪因子与妊娠期糖尿病胰岛素抵抗的相关性研究

目的了解妊娠期糖尿病（GDM）孕妇血清脂肪细胞因子内脂素、脂联素、肿瘤坏死因子-α表达水平的变化,探讨其与妊娠期糖尿病胰岛素抵抗的相关性。方法选择2008年12月-2009年3月在复旦大学附属妇产科医院产科门诊行常规产前检查并足月入院待产的孕妇。其中正常对照组22例,GDM组20例。检测人体测量参数和生化指标。采用ELISA方法检测两组血清内脂素、脂联素、肿瘤坏死因子-α（TNF-α）水平。用最小稳态模型计算胰岛素抵抗指数（HOMA—IR）：空腹血糖（FPG）×空腹胰岛素（FINS）／22．5。结果（1）GDM组血清内脂素（[7．9±2．0]vs[6．2±1．4]ng／ml,P〈0．01）与TNF-α（90．0±30．0）vs[53．7±48．0]pg／ml,P〈0．01）水平显著高于正常对照组。而GDM组血清脂联素水平较正常对照组明显下降（[309．0±210．4]vs[584．9±419．4]Pg／ml,P〈0．05）。（2）研究对象总体中内脂素与餐后1h血糖（1hPG）呈显著正相关（r=0．432,P=0．004）,而与脂联素呈明显负相关（r=-0．374,P=0．015）。脂联素与1hPG及内脂素呈显著负相关（r=-0．442,P=0．003;r=-0．374,P=0．015）。TNF—α与FINS、HOMA-IR呈显著正相关（r=0．376,P=0．014;r=0．320,P：0．039）（3）多因素Logistic逐步回归分析结果显示排除1hPG影响后GDM与脂联素（B=-0．030,P=0．041,OR=0．997,95％CI0．993—1．000）呈显著负相关,与FINS（B=0．620,P=0．029,OR=1．859,95％CI1．067—3．239）呈显著正相关。进一步校正FINS后内脂素（B=0．527,P=0．042,OR=1．694,95％CI1．020～2．815）、TNF-α（B=0．036,P=0．008,OR=1．037,95％CI1．010—1．065）成为GDM的独立影响因子。结论妊娠糖尿病孕妇血清内脂素、脂联素和TNF-α水平的改变与妊娠期胰岛素抵抗有关并可能通过不同的作用途径参与妊娠期糖尿病的发生和发展。     

Serum visfatin is associated with type 2 diabetes mellitus independent of insulin resistance and obesity

Objective

The aim of this study was to evaluate the association of serum visfatin, adiponectin and leptin with 2 diabetes mellitus (T2DM) in the context of the role of obesity or insulin resistance, which is not well understood.

Methods

A total of 76 newly-diagnosed T2DM patients and 76 healthy control subjects, matched for age, body mass index (BMI) and sex ratio, were enrolled. Anthropometric parameters, glycemic and lipid profile, insulin resistance (measured by homeostasis model assessment of insulin resistance index [HOMA-IR]), leptin, adiponectin, and visfatin were assessed.

Results

On the contrary to adiponectin, serum leptin and visfatin levels were higher in T2DM patients compared with controls (10.07 ± 4.5, 15.87 ± 16.4, and 5.49 ± 2.4 vs. 12.22 ± 4.9 μg/ml, 8.5 ± 7.8 ng/ml and 3.58 ± 2.2 ng/ml, respectively, P < 0.01). Waist circumference and BMI were correlated with leptin and adiponectin but not with visfatin. Leptin, adiponectin and visfatin all were associated with T2DM following adjusting for obesity measures. After controlling for HOMA-IR, visfatin remained as an independent predictor of T2DM (odds ratio = 1.32, P < 0.05). In a multiple regression analysis to determine visfatin only triglycerides and fasting glucose remained in the model (P < 0.05).

Conclusion

Elevation of visfatin in T2DM is independent of obesity and insulin resistance and is mainly determined by fasting glucose and triglycerides.     

Elevated serum levels of visfatin in gestational diabetes: a comparative study across various degrees of glucose tolerance

Aims/hypothesis Concentrations of visfatin are increased in insulin-resistant conditions, but the relationship between visfatin and insulin and/or insulin resistance indices in pregnancy remains unclear. Insulin resistance in pregnancy is further accentuated in women with gestational diabetes mellitus (GDM). Thus we assessed serum levels of visfatin in pregnant women with varying degrees of glucose tolerance. Materials and methods Fasting visfatin levels were measured at 28 weeks of gestation in 51 women divided according to their response to a 50-g glucose challenge test (GCT) and a 75-g OGTT: control subjects (n = 20) had normal responses to both a GCT and an OGTT; the intermediate group (IG; n = 15) had a false-positive GCT, but a normal OGTT; the GDM group (n = 16) had abnormal GCTs and OGTTs. Results There were no age or BMI differences between analysed groups. Across the subgroups there was a progressive increase in glucose and insulin at 120 min of the OGTT (p < 0.01). This was accompanied by an increase in visfatin, from 76.8 ± 14.1 ng/ml in the control subjects, to 84.0 ± 14.7 ng/ml in the IG group and 93.1 ± 12.3 ng/ml in the GDM group (p < 0.01 for GDM vs control subjects). There was a positive correlation between visfatin and fasting insulin (r = 0.38, p = 0.007) and insulin at 120 min of the OGTT (r = 0.39, p = 0.006). Conclusions/interpretation An increase in fasting visfatin, the levels of which correlate with both fasting and post-glucose-load insulin concentrations, accompanies worsening glucose tolerance in the third trimester of pregnancy. However, the significance of these findings, and in particular the role of visfatin in the regulation of insulin sensitivity during pregnancy, remains to be elucidated. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorised users. G. M. Prelevic and H. S. Randeva are both senior authors.     

2型糖尿病非糖尿病一级亲属中肥胖患者血浆内脂素水平

检测了2型糖尿病一级亲属、单纯肥胖和健康对照者内脂素（visfatin）、内皮依赖性血管舒张功能、颈总动脉内膜中层厚度，并用MRI评价内脏脂肪和皮下脂肪面积。结果提示2型糖尿病一级亲属中肥胖患者和单纯肥胖患者内脂素水平高于2型糖尿病一级亲属非肥胖者和健康对照组，并且内脂素与空腹血糖呈独立负相关。     

NF-κB介导大鼠肾小球系膜细胞Visfatin对肾素血管紧张素系统mRNA表达的影响

目的观察大鼠肾小球系膜细胞中内脏脂肪素（Visfatin）对肾素血管紧张素系统（RAS）mRNA表达的影响及探讨其机制。方法分别构建Visfatin表达载体质粒及Visfatin RNAi表达载体质粒,将细胞分为8组：正常糖对照组、正常糖＋NF-κB特异性抑制剂吡咯烷二硫基甲酸酯（PDTC）组、过表达Visfatin组、过表达Visfatin＋PDTC组、空白过表达载体组、空白过表达载体＋PDTC组、Visfatin RNAi组及空白沉默载体组,用Realtime-PCR方法检测血管紧张素原（AGT）、血管紧张素转化酶（ACE）、血管紧张素Ⅱ1型受体（AT1R）、血管紧张素Ⅱ2型受体（AT2R）等RAS相关基因表达,使用电泳迁移率变动分析法（EMSA）检测NF-κB活性,比较各组间基因表达及NF-κB活性的差异;以及通过观察PDTC处理对照组、过表达Visfatin组、空白过表达载体组前后上述指标的变化。结果细胞过表达Visfatin后,NF-κB活性、Visfatin、AGT、AT1R mRNA表达量显著升高,分别为正常糖对照组的1.52、11.42、2.85、1.25倍（P均〈0.01）;转染RNAi质粒pSIREN-Visfatin/sh RNA后,NF-κB活性、Visfatin、AGT、AT1R mRNA表达量显著降低,分别为正常糖对照组的10.90%、26.83%、30.00%、73.47%（P均〈0.01）。经PDTC处理的各组NF-κB活性、AGT mRNA表达量与相应的未经PDTC处理组相比显著降低（P〈0.01）,正常糖＋PDTC干预组NF-κB活性、AGT mRNA表达量是正常糖对照组的21.60%、34.59%;过表达Visfatin＋PDTC干预组的NF-κB活性、AGT mRNA表达量是过表达Visfatin组的37.96%、19.72%;空白过表达载体＋PDTC干预组NF-κB活性、AGT mRNA表达量是空白表达载体组的52.53%、33.08%,差异均具有统计学意义（P〈0.01）。结论在大鼠肾小球系膜细胞中,Visfatin可通过NF-κB引起RAS相关基因表达的变化。     

新型脂肪因子与阻塞性睡眠呼吸暂停低通气综合征

阻塞性睡眠呼吸暂停低通气综合征(OSAHS)发病率逐年升高,已成为危害人类健康的主要疾病之一.关于OSAHS的发病机制目前尚未完全明确,但有研究证实与脂肪因子有关.脂肪因子促进脂肪细胞的分化、脂解,影响糖脂代谢,参与炎症反应、免疫应答,与OSAHS、肥胖的发生有密切的联系.本文将对三种新型脂肪因子 Chemerin、Visfatin、Obestatin研究进展作一综述.