Identification of Crocin as a New hIAPP Amyloid Inhibitor via a Simple Yet Highly Biospecific Screening System

Amylin (hIAPP) amyloid formation plays an important role in the pathogenesis of type 2 diabetes (T2D), which makes it a promising therapeutic target for T2D. In this study, we established a screening tool for identifying chemicals affecting hIAPP amyloid formation based on a reported genetic tool, which constantly tracks protein aggregates in Saccharomyces cerevisiae. In order to obtain the hIAPP with better aggregation ability, the gene of hIAPP was tandemly ligated to create 1×, 2×, 4× or 6×-hIAPP expressing strains. By measuring the cell density and fluorescence intensity of green fluorescent protein (GFP) regulated by the aggregation status of hIAPP, it was found that four intramolecular ligated hIAPP (4×hIAPP) could form obvious amyloids with mild toxicity. The validity and reliability of the screening tool were verified by testing six reported hIAPP inhibitors, including curcumin, epigallocatechin gallate and so on. Combined with surface plasmon resonance (SPR) and the screening tool, which could be a screening system for hIAPP inhibitors, we found that crocin specifically binds to hIAPP and acts inhibit amyloid formation of hIAPP. The effect of crocin was further confirmed by Thioflavin T (ThT) fluorescence and transmission electron microscopy (TEM) analysis. Thus, a screening system for hIAPP amyloid inhibitors and a new mechanism of crocin on anti-T2D were obtained as a result of this study.     

葛根素对2型糖尿病大鼠的治疗作用*

目的:观察葛根素对2型糖尿病(T2DM)大鼠的治疗作用。方法:采用高糖高脂饲料喂养加一次性腹腔注射60 mg/kg链脲佐菌素的方法建立T2DM 大鼠模型,随机分为正常组,模型组,二甲双胍(40 mg/kg)组,葛根素低、中、高剂量(40,80,160 mg/kg)组,每组10只大鼠;造模成功后,灌胃给药4周,每周测量大鼠体重和空腹血糖(FBG),末次给药24 h后取血,收集血清,检测各组大鼠的血糖、血清甘油三酯(TG)、总胆固醇(TC) 、低密度脂蛋白-胆固醇(LDL-C)水平、高密度脂蛋白-胆固醇(HDL-C),血清天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)活性,血清尿素氮(BUN)、肌酐(SCr)、尿酸(UA)水平。结果:干预4周后,与正常组比较,模型组大鼠体重显著降低(P＜0.01),FBG,TC,TG,LDL-C,ALT,AST,BUN,SCr,UA均显著升高(P＜0.01),而HDL-C 显著降低(P＜0.01);与模型组比较,二甲双胍组和葛根素各剂量组大鼠体重均显著增加(P＜0.01),FBG,TC,TG,LDL-C,ALT,AST,BUN,SCr,UA均显著降低(P＜0.01),而HDL-C显著升高(P＜0.01)。结论:葛根素能够减少T2DM大鼠体重降低幅度,降低血脂、血糖水平,可用于T2DM的治疗。     

SUMO4基因多态性与2型糖尿病的关系

为了探讨北京汉族人群小泛素样修饰蛋白4(Small ubiquitin-like modifier 4,SUMO4)基因多态性与2型糖尿病(Type 2 diabetes mellitus,T2DM)的关系,文章采用病例对照设计,选取404例T2DM患者(T2DM组)以及年龄、性别匹配的500例健康对照者(Control组)作为研究对象,应用聚合酶链反应-高分辨熔解曲线(PCR-HRM)技术结合测序验证法,检测SUMO4基因3个单核苷酸多态性位点(rs237025、rs237024及rs600739)的基因型与等位基因分布情况,比较T2DM组糖化血红蛋白(Hemoglobin A1c,HbA1c)在各基因型间的分布,并进行单倍型分析。结果显示:①rs237025的G等位基因在T2DM组出现的频率更高(0.334 vs.0.282,P=0.017);GA基因型携带者患T2DM的风险是AA基因型携带者的1.563倍(P=0.001;OR,1.563;95%CI,1.189-2.053);在显性模型(GG+GA vs.AA)分析中,G等位基因携带者(GG+GA)患T2DM的风险是AA基因型携带者的1.525倍(P=0.002;OR,1.525;95%CI,1.169-1.989)。而rs237024和rs600739多态性未发现与T2DM的易感性相关(P>0.05)。②在T2DM组,rs237025的G等位基因携带者、rs237024的TT基因型携带者及rs600739的GG基因携带者具有较高的HbA1c水平,但各基因型携带者之间HbA1c水平并无统计学差异(P>0.05)。③单倍型AAC、AGC及GGT与T2DM的易感性正相关(OR>1);而单倍型AAT、GAC与T2DM的易感性负相关(OR<1)。据此得出结论:rs237025多态性与北京汉族人群T2DM的易感性相关,rs237024和rs600739多态性可能与T2DM的易感性不相关。     

SUMO4基因多态性与2型糖尿病的关系

为了探讨北京汉族人群小泛素样修饰蛋白4(Small ubiquitin-like modifier 4, SUMO4)基因多态性与2型糖尿病(Type 2 diabetes mellitus, T2DM)的关系, 文章采用病例对照设计, 选取404例T2DM患者(T2DM组)以及年龄、性别匹配的500例健康对照者(Control组)作为研究对象, 应用聚合酶链反应-高分辨熔解曲线(PCR-HRM)技术结合测序验证法, 检测SUMO4基因3个单核苷酸多态性位点(rs237025、rs237024及rs600739)的基因型与等位基因分布情况, 比较T2DM组糖化血红蛋白(Hemoglobin A_1c, HbA_1c)在各基因型间的分布, 并进行单倍型分析。结果显示：①rs237025的G等位基因在T2DM组出现的频率更高(0.334 vs. 0.282, P =0.017); GA基因型携带者患T2DM的风险是AA基因型携带者的1.563倍(P=0.001; OR, 1.563; 95% CI, 1.189-2.053); 在显性模型(GG+GA vs. AA)分析中, G等位基因携带者(GG+GA)患T2DM的风险是AA基因型携带者的1.525倍(P =0.002; OR, 1.525; 95% CI, 1.169-1.989)。而rs237024和rs600739多态性未发现与T2DM的易感性相关(P >0.05)。②在T2DM组, rs237025的G等位基因携带者、rs237024的TT基因型携带者及rs600739的GG基因携带者具有较高的HbA_1c水平, 但各基因型携带者之间HbA_1c水平并无统计学差异(P >0.05)。③单倍型AAC、AGC及GGT与T2DM的易感性正相关(OR>1); 而单倍型AAT、GAC与T2DM的易感性负相关(OR<1)。据此得出结论：rs237025多态性与北京汉族人群T2DM的易感性相关, rs237024和rs600739多态性可能与T2DM的易感性不相关。     

肠道菌群在2型糖尿病合并骨质疏松中的作用探析

骨质疏松是一种隐匿性骨密度降低的全身骨代谢性疾病,具有较高的致残率及致死率,严重影响患者生活质量。而骨质疏松作为糖尿病在骨骼系统中的常见并发症,在临床治疗中却忽略了二者之间存在的内在联系,采用分开诊治的方案。大量研究表明,肠道菌群与多种代谢性疾病相关,而2型糖尿病患者体内存在着明显的肠道菌群失调。因此考虑肠道菌群失调可能影响糖尿病合并骨质疏松的发生发展。本文通过深入阐明三者之间的关系,积极探索肠道菌群在糖尿病及骨质疏松中的作用,发现2型糖尿病患者肠道菌群失调,可导致胰岛素抵抗、炎症反应和胰岛素样生长因子 1缺少,进一步影响骨代谢过程,进而提出调节肠道菌群是治疗2型糖尿病合并骨质疏松的新方向。     

2型糖尿病鼠类模型的研究进展

小鼠、大鼠糖尿病模型对基础与临床防治研究十分重要,不同的研究目标对应不同的动物模型载体。本文就目前常用的2型糖尿病鼠类模型的构建、主要疾病特征及应用等进行评述,为研究者了解、选择适合的动物模型提供参考。     

Sense of coherence in people with and without type 2 diabetes mellitus: an observational study from Greece

Background Antonovsky''s concept of sense of coherence (SOC) has been suggested to relate to health, especially mental health and preventive health behaviours. Psychological distress has been identified as a risk factor for pre-diabetes and type 2 diabetes mellitus. The study of SOC and diabetes has not received much attention in Greece. This study aims to explore the extent to which type 2 diabetes mellitus can affect the SOC score.Methods An observational design was used to test the study hypothesis that individuals with type 2 diabetes mellitus would have a lower SOC than those without diabetes mellitus. A total of 202 individuals were studied, consisting of 100 people with diabetes mellitus (the study group) and 102 people with non-chronic orthopaedic conditions (the control group). All of the participants were patients of the Diabetic Clinic or the Orthopaedic Clinic of Livadia Hospital in Central Greece. SOC was assessed using a 29-item SOC questionnaire that had been translated into Greek and validated.Results Patients without type 2 diabetes mellitus had 2.4 times higher odds of having a high SOC score than patients with type 2 diabetes mellitus (P = 0.036; odds ratio [OR] = 2.35, 95% confidence interval [CI] = 1.06–5.23). Male patients had 3.9 times higher odds of having a high SOC score (P < 0.001; OR = 3.85, 95% CI = 1.71–8.67) than female patients. With regard to education, patients with a lower level of education had almost three times higher odds of having a high SOC score than patients with a higher level of education (P = 0.024; OR = 2.97, 95% CI = 1.15–7.67).Conclusions This study adds to the existing literature and indicates that SOC is a health asset. A study with an experimental design would clarify the interesting hypothesis of this study.     

Serum sialic acid levels and selected mineral status in patients with type 2 diabetes mellitus

The aim of the present study was to investigate whether altered serum total sialic acid (TSA), lipid-associated sialic acid (LSA), copper (Cu), manganese (Mn), zinc (Zn), chromium (Cr), iron (Fe), and magnesium (Mg) levels had an interactive connection with diabetes and also whether they were correlated with each other in diabetic patients. Two study groups (control and type 2 diabetic subjects) were included. Two hundred patients (108 female and 92 male), diagnosed and treated for type 2 diabetes in the Yuzuncu Yil University Hospital (Van, Turkey), were selected consecutively to represent type 2 diabetic patients. Fifty healthy individuals (29 female and 21 male) served as the control group matched for age, sex, body mass index, and smoking status were selected from hospital staff and other outpatient clinics. All participants had not taken vitamin or mineral supplements for at least 2 wk before sampling. Blood samples were drawn after an overnight fasting in both groups for the determination of serum glucose, TSA, LSA, Cu, Zn, Mn, Cr, Fe, and Mg. It was found that diabetics had higher TSA, LSA, Fe, Mn, Fe/Zn, and Cu/Zn levels, and lower Zn and Mg levels than those of controls. Although, Cu levels were higher, and Cr levels were lower in total and male diabetic patients, they were not different in female diabetic patients than in controls. The Cu/Fe ratio was lower in total and female diabetic patients, but not different in male diabetic patients than controls. The Zn/Cr ratio, on the other hand, was not different in diabetics than in controls. There was only a positive correlation between Fe-Mn levels in male diabetic patients. There was a negative correlation in LSA-Mn, Fe-Cu, Cu-Fe/Zn, and Mn-Cu/Zn levels in total diabetic patients. There was a positive correlation in TSA-Cr, TSA-Mg, LSA-Cu/Fe, LSA-Zn/Cr levels, and a negative correlation in TSA-Cu/Zn, LSA-Mn, Fe-Cu, Mn-Cu, Cu-Fe/Zn, Fe-cholesterol, and Cr-cholesterol in female diabetic patients. Our results showed that TSA, LSA, and selected minerals have interactive connections with diabetes mellitus (DM). There are also many sex-related positive or negative correlations between the altered parameters in diabetic patients. These parameters might be used as diagnostic index in patients with DM.     

脂蛋白脂酶基因多态性与2 型糖尿病的相关性研究

目的：探讨脂蛋白脂酶（lipoprotein lipase,LPL）基因PvuⅡ酶切多态性与2型糖尿病的相关性。方法：采用聚合酶链反应-限制性片段长度多态性（PGR-RFLP）方法,分析了156例样本LPL基因第6内含子PvuⅡ多态性（病例组98人。对照组58。其中40个2型糖尿病同胞对,病例组40人,对照组40人）。结果：病例组与对照组的基因型和基因频率均无显著性差异。结论：湖北汉族人群脂蛋白脂酶基因PvuⅡ酶切多态性与2型糖尿病无明显关联。     

Reactive metabolites and antioxidant gene polymorphisms in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM), by definition is a heterogeneous, multifactorial, polygenic syndrome which results from insulin receptor (IR) dysfunction. It is an outcome of oxidative stress caused by interactions of reactive metabolites (RMs) with lipids, proteins and other molecules of the human body. Production of RMs mainly superoxides (•O₂⁻) has been found in a variety of predominating cellular enzyme systems including nicotinamide adenine dinucleotide phosphate oxidase, xanthine oxidase, cyclooxygenase, endothelial nitric oxide synthase (eNOS) and myeloperoxidase. The four main RM related molecular mechanisms are: increased polyol pathway flux; increased advanced glycation end-product formation; activation of protein kinase C isoforms and increased hexosamine pathway flux which have been implicated in glucose-mediated vascular damage. Superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and NOS are antioxidant enzymes involved in scavenging RMs in normal individuals. Functional polymorphisms of these antioxidant enzymes have been reported to be involved in the pathogenesis of T2DM. The low levels of antioxidant enzymes or their non-functionality results in excessive RMs which initiates stress related pathways thereby leading to IR and T2DM. An attempt has been made to review the role of RMs and antioxidant enzymes in oxidative stress resulting in T2DM.     

2型糖尿病与糖尿病肾病患者微炎症及肠道微生物多样性分析

目的 分析2型糖尿病(T2DM)及糖尿病肾病(DKD)患者微炎症情况和肠道微生物多样性。 方法 将2016年4月至2019年7月在我院进行治疗的68例T2DM患者(T2DM组)和57例DKD患者(DKD组)纳入研究,选择同期于我院进行健康体检的36例志愿者作为对照组。收集3组对象一般资料、血液标本和粪便标本,测定血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDLC)、高密度脂蛋白胆固醇(HDLC)、糖化血红蛋白(HbAlc)、空腹血糖(FBG)、超敏C反应蛋白(hsCRP)、白细胞介素6(IL6)水平,并对肠道细菌进行16S rDNA序列测序。比较3组对象一般资料,血液指标,肠道菌群门水平构成情况,肠道菌群多样性,肠道菌属差异性,并对患者炎性指标与菌群种类进行相关性分析。 结果 DKD组患者糖尿病病程长于T2DM组(P结论 2型糖尿病患者普遍存在微炎症和肠道菌群失衡,微炎症程度与肾脏病变和肠道菌群数量密切相关。T2DM与DKD患者在肠道菌群结构上具有一致性和差异性,肠道菌群检测有可能成为预测T2DM患者发生肾脏病变的风险指标。     

HHEX gene polymorphisms and type 2 diabetes mellitus: A case-control report from Iran

Genome-wide association studies indicated that hematopoietically-expressed homeobox (HHEX) gene is a remarkable candidate for type 2 diabetes (T2D) mellitus susceptibility in spite of the fact that the results are ambiguous in some cases. So, this study aimed to evaluate the possible correlation between HHEX gene polymorphisms and T2D development in a sample of the Iranian population. The rs1111875G/A, rs7923837A/G, and rs5015480C/T HHEX gene polymorphisms were genotyped in 250 cases and 250 matched (age and sex) healthy controls using tetra-amplification-refractory mutation system-polymerase chain reaction method. The finding revealed the all measured inheritance models of rs1111875G/A and of rs5015480C/T variants dramatically increase the risk of T2D while another polymorphism (rs7923837A/G) was not associated with risk/protective role in T2D. The results indicated that rs1111875G/A and rs5015480C/T may contribute to the enhancement of T2D risk in a sample of the southeast Iranian population.     

2型糖尿病模型小鼠造模时间的选择

目的:分析不同时期的2型糖尿病小鼠血生化指标及心肌和肾脏的病理变化情况,为选择2型糖尿病模型小鼠造模时间提供依据。方法:32只健康雄性ICR小鼠高脂饲料喂养6周后,腹腔注射链脲佐菌素(STZ,30mg/kg),连续5d,制备糖尿病模型。9d后测空腹血糖(FBG),高于11.1mmol/L视为糖尿病模型。分别于成模后第4、6、8周处死一组小鼠。另取8只雄性ICR小鼠作为对照组,常规饲料喂养,于糖尿病组小鼠成模后第8周处死。分析小鼠生化及病理情况:①心脏、肾脏脏器系数计算;②血清乳酸脱氢酶(LDH)、肌酸激酶(CK)、肌酐(Cr)和尿素氮(BUN)含量测定;③HE染色观察心肌和肾脏组织病变的整体情况;Masson染色观察心肌组织纤维化情况;PAS染色观察肾脏组织病理变化。结果:与对照组小鼠进行比较,第4、6、8周的糖尿病小鼠心脏器系数升高,血清LDH、CK升高,病理组织学见心肌细胞肥大,纤维化;肾脏脏器系数升高,肾功能肌酐(Cr)、尿素氮(BUN)显著升高,病理组织学见肾小球肥大,肾小管基底膜增厚,管腔萎缩。结论:第6周糖尿病小鼠相关生化病理指标改变相对明显且饲养时间相对较短,故2型糖尿病模型小鼠造模后第6周是进行药物干预和病理、生理、生化等研究的最佳时间。     

肠道菌群对2型糖尿病的调节机制

2型糖尿病(type 2 diabetes mellitus,T2DM)是一种遗传和环境因素共同作用的复杂的代谢性疾病,约占糖尿病患者总数的90％以上.以往,人们一直认为导致T2DM发生的肥胖是外部因素所致,但目前已有证据表明,身体内部因素同样是导致肥胖的诱因之一.人体微生物群的最新研究表明,个体肠道中的特定菌群可能促...     

Morningness–eveningness questionnaire score and metabolic parameters in patients with type 2 diabetes mellitus

“Morningness” and “Eveningness” represent lifestyle patterns including sleep–wake patterns. Although previous studies described a relationship between the morningness–eveningness trait and glycemic control in patients with type 2 diabetes mellitus (T2DM), the mechanism underlying this association remains unknown. The study participants comprised 725 Japanese T2DM outpatients free of history of cardiovascular diseases. Various lifestyles were analyzed using self-reported questionnaires, including morningness–eveningness questionnaire (MEQ). The relationships between morningness–eveningness trait and various biochemical parameters were investigated by linear regression analysis and logistic regression analysis. We classified the study patients into three groups, morning type (n?=?117), neither type (n?=?424) and evening type (n?=?184). Subjects of the evening type had high levels of alanine aminotransferase, triglyceride, fasting blood glucose and HbA1c and low high-density lipoprotein-cholesterol level in a model adjusted for age and gender. Furthermore, multivariate analysis showed that the evening type was associated with high HbA1c and estimated glomerular filtration rate even after adjustment for other lifestyle factors known to affect metabolic control. The results suggest that T2DM patients with eveningness trait are under inadequate metabolic control independent of other lifestyle factors. Thus, the evening trait of T2DM patients represents an important target for intervention to ensure appropriate metabolic function.     

Routine enzymes in the monitoring of type 2 diabetes mellitus

We examined the relationships of glucose and HbA1c levels with the routinely screened serum enzyme activities in type 2 diabetes mellitus, and we designed an in vitro study to evaluate the direct effect of glucose levels on enzyme activities. The study was performed on a consecutive series of outpatients with type 2 diabetes who were followed up at Dicle University Medical Faculty Hospital from May 2009 to May 2010 for the first time. Effects of aspartate transaminase, aminotransferase, gamma‐glutamyl transferase (GGT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) activities, glucose and HbA1c levels and in vitro glucose (492, 287, 184, 131, 82 mg dl⁻¹, respectively) on enzymes were determined. The patients were categorized on the basis of glucose and HbA1c levels and grouped according to a range of values. In patients with high HbA1c levels (>10.1%), ALP, GGT activities and creatine kinase (CK)‐MB/CK (p = 0.008, 0.026, 0.014) ratio were increased significantly when compared with those in the control group. In patients with high glucose levels (>200 mg dl⁻¹), ALP, GGT activities and CK‐MB/CK ratio (p = 0.003, 0.001, 0.001) were increased significantly when compared with those in the control group. Glucose, which was added to serum in different concentrations in vitro, did not directly affect enzyme activities such as ALP, GGT and CK. We concluded that increased glucose levels could damage the liver and the heart muscle cells. Monitoring of blood glucose levels is a more valuable parameter than monitoring HbA1c in the momentary evaluation of diabetes. Copyright © 2011 John Wiley & Sons, Ltd.     

The future of protein biomarker research in type 2 diabetes mellitus

Introduction: The onset of type 2 diabetes mellitus (T2DM) is strongly associated with obesity and subsequent perturbations in immuno-metabolic responses. To understand the complexity of these systemic changes and better monitor the health status of people at risk, validated clinical biomarkers are needed. Omics technologies are increasingly applied to measure the interplay of genes, proteins and metabolites in biological systems, which is imperative in understanding molecular mechanisms of disease and selecting the best possible molecular biomarkers for clinical use.

Areas covered: This review describes the complex onset of T2DM, the contribution of obesity and adipose tissue inflammation to the T2DM disease mechanism, and the output of current biomarker strategies. A new biomarker approach is described that combines published and new self-generated data to merge multiple -omes (i.e. genome, proteome, metabolome etc.) toward understanding of mechanism of disease on the individual level and design multiparameter biomarker panels that drive significant impacts on personalized healthcare.

Expert commentary: We here propose an approach to use cross-omics analyses to contextualize published biomarker data and better understand molecular mechanisms of health and disease. This will improve the current and future innovation gaps in translation of discovered putative biomarkers to clinically applicable biomarker tests.