TWEAK/Fn14及NF-κB通路的关键因子mRNA及蛋白表达差异与老年人肥胖的相关性研究?

目的 研究老年人外周血PBMC中TWEAK/Fn14及激活下游NF-κB通路的关键因子mRNA及蛋白表达差异与老年人中心性肥胖的相关性。方法 在新疆农牧区常住居民横断面流行病学调查数据库中随机抽取80例研究对象（对照组40例，肥胖组40例），提取空腹外周血中PBMC，采用qRT-PCR、Western blot方法检测TWEAK、Fn14、IKKα、IKKβ、NF-κBp65的mRNA表达、蛋白表达。结果 肥胖组人外周血PBMC中的Fn14、IKKα、IKKβ的mRNA表达高于对照组(P<0．05)；TWEAK、NF-κBp65的mRNA表达也高于对照组，但差异无统计学意义(P>0．05)。肥胖组的Fn14、IKKα、IKKβ蛋白表达水平高于对照组(P<0．05)，两组间TWEAK、NF-κBp65蛋白表达水平差异无统计学意义(P>0．05)。双变量Pearson相关性分析显示，上述因子的mRNA表达水平，TWEAK与Fn14呈正相关（r=0.472，P<0．01），Fn14与IKKα、IKKβ均呈正相关（r=0.262、0.275，P<0．05）； IKKα、IKKβ与NF-κBp65均呈正相关（r=0.747、0.692，P<0．01）。结论 新疆农牧区常驻老年人中心性肥胖与外周血PBMC中Fn14、IKKα、IKKβ的蛋白、mRNA的高表达相关，TWEAK/Fn14可能通过调节IKK激活NF-κB炎症通路，参与人类肥胖的发生、发展。     

核因子κB通路参与缺氧诱导心肌细胞分泌肿瘤坏死因子α

目的:探讨缺氧刺激能否诱导体外培养心肌细胞分泌肿瘤坏死因子α(TNF-α),核因子κB(NF-κB)通路是否参与其中,并发挥调节作用。方法:1%O2物理缺氧刺激原代SD大鼠乳鼠心肌细胞,在不同时间点Real-time PCR检测TNF-αmRNA水平;ELISA检测培养上清中TNF-α蛋白水平;Western blot检测胞质NF-κB相关通路蛋白IKKα,IKKβ,IKKBα蛋白及磷酸化蛋白水平以及胞核NF-κB p65蛋白表达;电泳迁移率实验检测NF-κB DNA结合能力。缺氧同时给予NF-κB抑制剂四氢化吡咯二硫代氨基甲酸酯(PDTC)刺激心肌细胞,检测细胞核p65蛋白表达,TNF-αmRNA及蛋白水平。结果:缺氧诱导原代心肌细胞表达TNF-α,TNF-αmRNA水平从缺氧1h开始升高,12h及24h达峰值;其蛋白分泌从缺氧6h开始升高,12h和24h达峰值。缺氧激活NF-κB通路:缺氧5min胞质pIKKα/IKKβ表达开始上调,30min达峰值,持续6h;IKKBα表达缺氧5min开始降低,而pIKKBα缺氧30min开始增加;胞核p65蛋白水平缺氧5min上调,1h达峰值,持续6h;NF-κB DNA结合能力缺氧5min后开始增强。PDTC抑制NF-κB活性,有效抑制TNF-αmRNA及其蛋白表达。结论:缺氧通过激活NF-κB通路,诱导心肌细胞自分泌TNF-α,NF-κB在缺氧诱导心肌细胞自分泌TNF-α过程中起正向调节作用。     

核因子κB和缺氧诱导因子1在慢性阻塞性肺疾病患者外周血单个核细胞中的表达

目的 探讨核因子κB (NF-κB)和缺氧诱导因子1(HIF-1)在老年慢性阻塞性肺疾病(COPD)患者外周血单个核细胞(PBMC)中的表达,明确NF-κB和HIF-1在COPD发病机制中的作用.方法 通过Western blotting法、实时荧光定量PCR法分别测定稳定期COPD患者(中度以上,30例)、对照组(30例)PBMC的NF-κB、HIF-1蛋白水平和NF-κB、HIF-1 mRNA水平.结果 COPD组PBMC细胞中NF-κB mRNA、HIF-1 mRNA水平均显著高于对照组(0.013±0.010比0.005±0.003,P＜0.01;0.030±0.025比0.008±0.006,P＜0.01).COPD组PBMC细胞核中NF-κB、HIF-1蛋白表达均高于对照组,差异有统计学意义(1.08±0.12比0.87±0.09,P＜0.01;1.12±0.09比0.97±0.17,P=0.002).NF-κB蛋白在各COPD组差异有统计学意义(P＜0.01),与FEV1％ pred呈显著负相关(r=-0.657,P ＜0.01).NF-κB mRNA、HIF-1 mRNA、HIF-1蛋白在各COPD组差异均无统计学意义,与FEV1％pred均无相关性(P值均＞0.05).NF-κB mRNA与HIF-1 mRNA呈正相关(r=0.673,P＜0.01),NF-κB、HIF-1蛋白表达呈正相关(r=0.56,P=0.001).结论 COPD患者PBMC中NF-κB、HIF-1mRNA水平及蛋白水平表达均增加,且HIF-1在各严重程度的COPD中稳定表达,NF-κB蛋白表达与疾病严重程度相关.表明中度以上COPD患者在慢性持续性缺氧的情况下既启动了全身的炎症反应同时也启动了适应性保护机制.     

核因子-κB激酶2抑制剂对小鼠非酒精性脂肪性肝炎的保护作用

非酒精性脂肪性肝炎( nonalcoholic steatohepatitis,NASH)的发病率正逐年升高[1],“二次打击”假说已被广泛接受,胰岛素抵抗始终贯穿其中,炎性反应、脂质过氧化和氧应激发挥重要作用[2-3].核因子-κB(NF-κB)是最早被研究的氧化应激调节靶因子之一,NF-κB激酶(IKK)是一个很大的蛋白复合体,包含2个激酶亚单位[IKKα(IKK1)和IKKβ( IKK2)]以及1个调节亚单位NEMO(NF-κBessential modifier)或IKKγ.IKK经活化磷酸化,可激活NF-κB,进而释放多种炎性反应因子.本研究拟通过建立动物NASH模型,研究IKK2-NF-κB信号途径中各炎性反应因子的表达,探讨IKK2抑制剂对NASH的保护作用.     

血管紧张素（1-7）对糖尿病大鼠胰岛素抵抗的影响及机制研究

目的探讨血管紧张素(1-7)[Ang-(1-7)]对DM大鼠IR的影响及可能机制。方法随机选取Wistar大鼠10只为正常对照组(NC),另取24只予高脂饮食喂养联合STZ注射构建DM模型,造模成功的20只大鼠随机分为糖尿病组(DM)、Ang-(1-7)组[Ang-(1-7)300μg/(kg.d)皮下注射],每组各10只。干预8周后检测FPG、FIns及血管紧张素II(Ang II)水平,计算稳态模型胰岛素抵抗指数(HOMA-IR)及敏感指数(HOMA-ISI),观察肝脏病理改变,检测肝脏炎症通路及Ins信号转导通路相关因子的mRNA及蛋白表达。结果与NC组比较,DM、Ang-(1-7)组体重、FIns、HOMA-ISI、IRS-2 mRNA、磷脂酰肌醇3激酶(PI3K)mRNA和蛋白、丝氨酸/苏氨酸蛋白激酶2(Akt-2)mRNA和蛋白表达降低(P0.05),FPG、Ang II、HOMA-IR、肝脏指数、IκB激酶β(IKKβ)mRNA和蛋白、核因子κB(NF-κB)mRNA和蛋白、TNF-αmRNA、IL-6 mRNA、糖原合成酶激酶3α(GSK-3α)mRNA和蛋白表达升高(P0.05)。与DM组比较,Ang-(1-7)组FPG、Ang II、HOMA-IR、肝脏指数、IKKβmRNA和蛋白、NF-κB mRNA和蛋白、TNF-αmRNA、IL-6 mRNA、GSK-3αmRNA和蛋白表达降低,FIns、HOMA-ISI、IRS-2 mRNA、PI3K m RNA和蛋白、Akt-2 mRNA和蛋白表达升高(P0.05)。结论 Ang-(1-7)可能通过抑制肝脏IKKβ/NF-κB炎症通路及上调IRS-2/PI3K/Akt-2胰岛素信号通路,改善IR。     

异鼠李素对高糖高脂诱导胰岛β细胞损伤保护作用的研究

目的探讨异鼠李素(ISO)对高糖高脂诱导小鼠胰岛β细胞株MIN6细胞损伤的保护作用及机制。方法不同浓度ISO预处理MIN6细胞后高糖高脂培养48 h,CCK8法筛选ISO最佳干预浓度。细胞分为正常对照(Con)组(11. 1 mmol/L葡萄糖)、高糖高脂损伤模型(M)组(33. 3 mmol/L葡萄糖+0. 25 mmol/L棕榈酸)及ISO预处理(ISO+M)组(10μmol/L ISO+33. 3 mmol/L葡萄糖+0. 25 mmol/L棕榈酸)。流式细胞术测定各组细胞凋亡率;硝酸还原酶法检测一氧化氮(NO)含量;RT-PCR测定IL-1β、IL-6、肿瘤坏死因子α(TNF-α)mRNA表达;Western blot法检测磷酸化核因子κB(NF-κB)抑制蛋白(IκB)激酶β(p-IKKβ)、磷酸化NF-κB抑制蛋白α(p-IκBα)、诱导型一氧化氮合酶(iNOS)及NF-κB p65蛋白的表达。结果细胞凋亡及NO含量M组高于Con组,ISO+M组低于M组(P0. 01)。IL-1β、IL-6、TNF-αmRNA,p-IKKβ、p-IκB、iNOS蛋白与NF-κB p65蛋白表达M组高于Con组,ISO+M组低于M组(P0. 05)。结论 ISO可减轻高糖高脂诱导的胰岛β细胞损伤,可能与抑制IκB激酶(IKK)/IκB/NF-κB/iNOS通路活性有关。     

眼针对脑缺血再灌注损伤模型大鼠脑皮层组织IKKβ/NF-κB表达的影响

目的 观察眼针对脑缺血再灌注损伤(CIRI)模型大鼠脑皮层组织中IκB激酶β(IKKβ)及核因子-κB (NF-κB)表达,探讨眼针治疗脑损伤的作用机制.方法 健康雄性SPF级Wistar雄性大鼠60只,随机分为正常组、假手术组、CIRI模型组和眼针组.CIRI模型组和眼针组采用改良的线栓法建立大鼠大脑中动脉缺血(MACO)再灌注动物模型.Western blot检测大鼠缺血侧脑皮层IKKβ、NF-κB蛋白表达的变化.结果 与正常组及假手术组比较,模型组大鼠缺血侧脑皮层组织IKKβ及NF-κB蛋白水平均显示出高表达(P＜0.01),眼针组同模型组相比,IKKβ及NF-κB蛋白表达则下调(P＜0.01).结论 眼针抑制脑皮层组织中IKKβ及NF-κB的表达,可能是眼针治疗CIRI的主要作用机制之一.     

山奈酚延缓自发性肥胖2型糖尿病小鼠肾损伤研究

目的观察山奈酚(KPF)干预自发肥胖2型糖尿病小鼠(db/db鼠)早期糖尿病肾病,并探讨相关机制。方法 24只健康雄性10周龄db/db鼠随机分为四组:不同剂量KPF给药组(50、200mg/kg)、db/db对照组和二甲双胍(0.2g/kg)阳性对照组,并设db/m对照组。连续灌胃给药10周,检测小鼠血清肌酐(SCr)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α),24小时尿白蛋白排泄率(UAER);留取肾组织,作病理形态学检查、实时定量PCR检测肾组织TNF-α、IL-6的m RNA表达、Western blot检测磷酸化核因子κB p65(p-NF-κBp65)、磷酸化核因子κB抑制蛋白α(p-IκBα)、核因子κB抑制蛋白α激酶(IKKα)蛋白的表达水平。结果不同剂量KPF干预10周,都能使db/db小鼠24小时UAER、SCr、IL-6、TNF-α水平下降,肾组织IL-6、TNF-α基因表达水平明显降低(P0.01、0.05),p-NF-κBp65、IKKα和p-IκBα蛋白表达水平下降(P0.01)。结论 KPF可通过抑制核因子κB(NF-κB)介导的炎症反应,对自发2型糖尿病小鼠早期的肾脏损害起到保护作用。     

α3神经型尼古丁乙酰胆碱能受体在阿尔茨海默病中的抗炎作用

目的 探讨α3nAChRs在阿尔茨海默病(AD)中的抗炎作用.方法 应用Western印迹,ELISA及实时定量PCR检测各组细胞核因子(NF-κBp65)和炎性趋化因子单核细胞趋化蛋白1(MCP-1),巨噬细胞炎性蛋白-1α(MIP-1α),肿瘤坏死因子-α(TNF-α)的蛋白及mRNA表达情况.结果 与对照组比较,淀粉样蛋白(Aβ)处理α3nAChRsiRNA SH-SY5Y细胞NF-κBp65、TNF-α蛋白及mRNA表达增加(P＜0.05);MCP-1、MIP-1α表达变化不明显.结论 Aβ引起SH-SY5Y α3nAChR siRNA细胞NF-κBp65、TNF-α蛋白及mRNA表达升高,α3nAChR可能具有一定抗炎作用.     

肿瘤坏死因子-α对单核细胞妊娠相关血浆蛋白A表达的影响及调节机制

目的探讨肿瘤坏死因子-α(TNF-α)对人外周血单核细胞妊娠相关血浆蛋白(PAPP)-A蛋白和mRNA表达的影响及其机制。方法采用密度梯度离心法分离及培养人外周血单核细胞,采用Western印迹法和实时荧光定量PCR法观察TNF-α诱导单核细胞PAPP-A蛋白和mRNA表达的时间及剂量效应。采用TransAMTM技术检测TNF-α对单核细胞NF-κB活性的影响。此外观察给予核转录因子κB(NF-κB)抑制剂BAY11-70682预处理后,TNF-α对单核细胞PAPP-A表达的影响。结果 TNF-α(100 ng/ml)刺激单核细胞后,PAPP-A的蛋白和mRNA表达分别在8 h和2 h达高峰,且呈剂量依赖性诱导单核细胞的PAPP-A表达。TNF-α可显著增加单核细胞的磷酸化NF-κB p65水平,在给与BAY11-70682预处理后,TNF-α诱导PAPP-A表达的作用受到抑制。结论促炎因子TNF-α通过激活NF-κB途径上调单核细胞PAPP-A的蛋白和基因表达,这可能是急性冠脉综合征(ACS)患者血清PAPP-A升高的机制之一。     

Tau protein and beta protein

The main pathological features of Alzheimer's disease are Alzheimer neurofibrillary tangles and senile plaques. Recent biochemical research revealed that tangles are composed of tau protein and ubiquitin and amyloid in senile plaques is composed of beta protein which is a fragment of the membrane receptor protein. Although fraction, other data suggest that whole molecules become abnormal and aggregate into PHF. On the other hand, beta protein is a small cleavage product of the precursor protein. It is not concluded yet whether abnormal precursor proteins exist or not. Recent research in this field is reviewed.     

Evolution of protein structural classes and protein sequence families

In protein structure space, protein structures cluster into four elongated regions when mapped based solely on similarity among the 3D structures. These four regions correspond to the four major classes of present-day proteins defined by the contents of secondary structure types and their topological arrangement. Evolution of and restriction to these four classes suggest that, in most cases, the evolution of genes may have been constrained or selected to those genetic changes that results in structurally stable proteins occupying one of the four "allowed" regions of the protein structure space, "structural selection," an important component of natural selection in gene evolution. Our studies on tracing the "common structural ancestor" for each protein sequence family of known structure suggest that: (i) recently emerged proteins belong mostly to three classes; (ii) the proteins that emerged earlier evolved to gain a new class; and (iii) the proteins that emerged earliest evolved to become the present-day proteins in the four major classes, with the fourth-class proteins becoming the most dominant population. Furthermore, our studies also show that not all present-day proteins evolved from one single set of proteins in the last common ancestral organism, but new common ancestral proteins were "born" at different evolutionary times, not traceable to one or two ancestral proteins: "the multiple birth model" for the evolution of protein sequence families.     

Synaptic regulation of protein synthesis and the fragile X protein

Protein synthesis occurs in neuronal dendrites, often near synapses. Polyribosomal aggregates often appear in dendritic spines, particularly during development. Polyribosomal aggregates in spines increase during experience-dependent synaptogenesis, e.g., in rats in a complex environment. Some protein synthesis appears to be regulated directly by synaptic activity. We use "synaptoneurosomes," a preparation highly enriched in pinched-off, resealed presynaptic processes attached to resealed postsynaptic processes that retain normal functions of neurotransmitter release, receptor activation, and various postsynaptic responses including signaling pathways and protein synthesis. We have found that, when synaptoneurosomes are stimulated with glutamate or group I metabotropic glutamate receptor agonists such as dihydroxyphenylglycine, mRNA is rapidly taken up into polyribosomal aggregates, and labeled methionine is incorporated into protein. One of the proteins synthesized is FMRP, the protein that is reduced or absent in fragile X mental retardation syndrome. FMRP has three RNA-binding domains and reportedly binds to a significant number of mRNAs. We have found that dihydroxyphenylglycine-activated protein synthesis in synaptoneurosomes is dramatically reduced in a knockout mouse model of fragile X syndrome, which cannot produce full-length FMRP, suggesting that FMRP is involved in or required for this process. Studies of autopsy samples from patients with fragile X syndrome have indicated that dendritic spines may fail to assume a normal mature size and shape and that there are more spines per unit dendrite length in the patient samples. Similar findings on spine size and shape have come from studies of the knockout mouse. Study of the development of the somatosensory cortical region containing the barrel-like cell arrangements that process whisker information suggests that normal dendritic regression is impaired in the knockout mouse. This finding suggests that FMRP may be required for the normal processes of maturation and elimination to occur in cerebral cortical development.     

Gene and protein sequences of adenovirus protein VII, a hybrid basic chromosomal protein.

The sequences of both the gene and the corresponding protein of adenovirus major core protein VII have been determined. The precise location of this gene is between 43.37 and 44.90 map coordinates on the viral genome. Protein VII is 173 residues long and has a molecular weight of 19,258. Detailed analysis of its sequence has revealed four basic domains separated by several predicted alpha helices. It is proposed that intrachain folding of protein VII is driven by hydrophobic interactions of the alpha helices, leaving the basic domains of the protein to interact with DNA phosphates. Protein monomers may further associate with each other in the formation of hexameric nucleosome-like particles. The displacement and replacement of protein VII during the viral infectious cycle in the host cell appears to mimic the biology of nucleoprotamine during the processes of spermatogenesis and fertilization. The presence of a protamine-like domain affirms a hybrid histone/protamine molecular structure for protein VII, although it may resemble the protamine in function.     

Pride and protein

Objective

In Jane Austen’s Pride and Prejudice, members of the Bennet family are either sensible or silly, and males are under-represented. This study searches for an underlying medical diagnosis that explains these features.

Design

Very retrospective literature review.

Participants

Mrs Bennet, her five daughters (Jane, Elizabeth, Mary, Kitty and Lydia), her brother (Mr Gardiner) and her sister (Mrs Phillips).

Main outcome measures

Family tree and associated phenotypes

Methods

The author read Pride and Prejudice. A Bennet family tree was constructed. The number of male and female descendants was analysed using a binomial model. For each character, evidence of behaviour was collected, and members of the Bennet family were categorised as either sensible or silly.

Results

Males are under-represented in Mrs Bennet’s family. Assuming an equal probability of male or female offspring, this reaches statistical significance (binomial model, P?=?0.03). Approximately 50 % of females in the family are silly. Silly behaviour is more prevalent during social gatherings.

Conclusions

The family tree suggests an X-linked genetic disorder, fatal in utero or in early life to affected males, explaining the paucity of male offspring. Female carriers survive, but with cognitive difficulties, explaining the approximate 50-50 distribution of sensible and silly females in the family. The exacerbation of silliness during social gatherings may suggest an effect of protein intake, raising suspicions of a disorder of protein metabolism. Ornithine transcarbamylase deficiency is one such condition. Unfortunately, there remain significant challenges in performing genetic testing on fictional characters, so definitive evidence remains elusive. Jane and Elizabeth Bennet do not show signs of the disorder. However, carriers may be asymptomatic; they should be offered genetic counselling before Bingley or Darcy offspring are considered.

     

Associations of protein C and protein S with serum lipid concentrations

Difficulties in the laboratory measurement of protein C and protein S levels cause problems in the diagnosis of deficiency states in individual patients and may complicate estimation of the prevalence of these states in the general population. Some difficulties may be due to unappreciated influences affecting the measured levels of proteins C and S. We measured protein C activity and antigen, total and free protein S antigen, and serum total cholesterol, high-density cholesterol and triglyceride in a community-based study of 150 adults (73 male, 77 female), age range 23–80 years. Participants were identified from the list of a single general practice by stratified random sampling within sex and decade of age. Protein C activity and antigen were strongly associated with serum lipids, mean levels increasing by approximately 0.25 u/ml as total cholesterol and triglyceride concentration each rose from the 5th to 95th centile. Total protein S antigen concentration was associated with total cholesterol, the mean rising by over 0.1 u/ml as total cholesterol increased from the 5th to the 95th centile, whilst a similar rise in triglyceride was associated with an increase in mean free protein S of more than 0.3 u/ml. Overall, physiological variation in total cholesterol and triglyceride concentration was associated with significant variation in protein C and protein S levels, independent of age and sex, suggesting that it is important to take serum lipids into account when investigating patients for protein C or protein S deficiency. Failure to do so may be misleading in some circumstances.