空腹血清C肽水平与伴或不伴糖尿病慢性心力衰竭患者心功能的关系

目的探讨伴或不伴糖尿病的慢性心力衰竭(chronic heart failure,CHF)患者入院时空腹血清C肽水平与心功能的关系。方法分析2017年7月至2018年12月于上海市浦东医院心内科住院的262例伴或不伴糖尿病的CHF患者,心功能为纽约心脏病学会(New York Heart Association,NYHA)分级Ⅱ~Ⅳ级,分为糖尿病组(80例)和非糖尿病组(182例)。同时随机选取62例在体检中心体检的无糖尿病和心脏疾病的研究对象作为对照组。分析糖尿病和非糖尿病的CHF患者空腹血清C肽水平与心功能的关系。结果(1)糖尿病组患者空腹血糖为(8.70±2.90)mmol/L、血清C肽为(0.78±0.67)nmol/L,非糖尿病组分别为(5.80±1.67)mmol/L、(0.56±0.61)nmol/L,对照组分别为(5.10±0.69)mmol/L、(0.16±0.12)nmol/L,3组比较差异均有统计学意义(P均<0.001),糖尿病组患者空腹血糖和血清C肽水平显著高于非糖尿病组和对照组(P均<0.01),非糖尿病组患者空腹血糖和血清C肽水平显著高于对照组(P<0.05或P<0.01);糖尿病组患者左心室射血分数(left ventricular ejection fraction,LVEF)为(44.1±8.3)%,非糖尿病组和对照组分别为(46.7±7.2)%、(64.8±3.8)%,3组比较差异有统计学意义(P<0.001),糖尿病组LVEF显著低于非糖尿病组和对照组(P均<0.01),非糖尿病组显著低于对照组(P<0.01);糖尿病组患者C反应蛋白(C reactive protein,CRP)为(1.39±0.91)mg/L、N末端B型利钠肽原(n-terminal pro-b-type natriuretic peptide,NT-pro BNP)为(1771.3±23.1)ng/L、血红蛋白为(125.6±16.7)g/L,非糖尿病组分别为(1.22±0.73)mg/L、(1659.2±19.3)ng/L、(126.1±16.5)g/L,对照组分别为(0.85±0.72)mg/L、(87.2±17.2)ng/L、(136.4±15.2)g/L,3组比较差异均有统计学意义(P均<0.001),糖尿病组和非糖尿病组患者CRP、PRO-BNP显著高于对照组(P均<0.01),血红蛋白水平均显著低于对照组(P均<0.01),糖尿病组和非糖尿病组间CRP、PRO-BNP和血红蛋白比较差异均无统计学意义(P均>0.05)。(2)在全部心力衰竭患者、糖尿病和非糖尿病心力衰竭患者,血清C肽水平在NYHAⅣ级组分别为(1.05±0.85)、(1.17±0.82)、(0.99±0.86)nmol/L,在NYHAⅢ级分别为(0.53±0.22)、(0.52±0.20)、(0.54±0.23)nmol/L,在NYHAⅡ级分别为(0.32±0.09)、(0.32±0.11)、(0.31±0.09)nmol/L。用协方差分析校正年龄、性别、吸烟、促胰岛素分泌降糖药物、体质量指数、血压、血清总胆红素(total bilirubin,TBIL)、丙氨酸氨基转移酶(alanine aminotransferase,ALT)、肌酐、血糖、血脂、白细胞计数(white blood cell count,WBC)和血红蛋白水平等因素后,在全部心力衰竭患者、糖尿病和非糖尿病心力衰竭患者血清C肽水平在NYHAⅣ级患者显著高于Ⅲ级和Ⅱ级患者(P均<0.01),在全部心力衰竭患者和非糖尿病心力衰竭患者,NYHAⅢ级组显著高于Ⅱ级者(P均<0.05)。同一NYHA分级的全部心力衰竭患者、糖尿病和非糖尿病心力衰竭患者间血清C肽比较差异均无统计学意义(P均>0.05)。(3)采用多元线性回归分析,调整因素包括年龄、性别、吸烟、体质量指数、血压、TBIL、ALT、肌酐、血糖、血脂、WBC和血红蛋白水平,结果表明:在全部心力衰竭患者、糖尿病和非糖尿病心力衰竭患者血清C肽水平与PRO-BNP正相关[偏回归系数:0.006,95%CI-0.016~0.028,P=0.007;偏回归系数:0.117,95%CI-0.042~0.277,P=0.006;偏回归系数:0.411,95%CI-0.149~0.971,P=0.023],与LVEF负相关[偏回归系数:-0.122,95%CI-0.285~0.041,P=0.004;偏回归系数:-0.008,95%CI-0.032~0.016,P=0.010;偏回归系数:-0.065,95%CI-0.139~0.011,P=0.036]。结论糖尿病和非糖尿病CHF患者空腹血清C肽水平显著升高,并且与心力衰竭严重程度相关。     

胰岛β细胞瘤12例临床分析

目的:探讨胰岛β细胞瘤的临床特点,避免误诊误治.方法:外科手术治疗并经病理确诊的12例胰岛β细胞瘤患者,分析其影像学检查资料、空腹血糖、胰岛素、C肽水平、胰岛素/血糖比值及治疗结果.结果:病理确诊为单发肿瘤11例,多发1例;术前B超检查10例,阳性4例(40％),CT检查10例,阳性9例(90％),核磁共振成像(MRI)检查4例,阳性3例(75％);所有患者空腹血糖范围为0.25～2.90 mmol/L,12例均＜ 3.0 mmol/L;胰岛素水平为4.63～82.09 mIU/L,12例＞3.0 mIU/L;C肽0.26 ～1 100.71 pmol/L,＞200 pmol/L者4例;低血糖发作时胰岛素释放指数＞0.4者7例(58％),5例胰岛素释放指数小于0.4,占总例数的42％;本组患者均为良性肿瘤,手术后均治愈.结论:当患者反复出现低血糖反应或不明原因神经精神症状时,应监测血糖,及时发现低血糖症并追究低血糖发生的原因,避免漏诊及误诊胰岛素β细胞瘤.     

Sustained insulin-induced remissions of juvenile diabetes by means of an external artificial pancreas

Summary Remission of diabetes was attempted in 12 recent acute onset ketosis-prone juvenile diabetes after short term (5±1 days) but excellent blood glucose control by the external artificial beta-cell. The comparison group comprised patients undergoing traditional treatment (n=28). Nine (75%) persistent (over 3–14 months of duration) although partial (oral drugs required) remissions were obtained in the former group as compared to 3 (11%) in the latter group (p<0.05). Cases which showed remissions after insulin infusion had a plasma insulin response to IV glucagon still present before insulin infusion, and a daily urinary C-peptide excretion significantly enhanced after (p<0.01). Urinary C-peptide /blood glucose remained improved during the remission period. Thus, early effective treatment by means of the artificial pancreas may break the vicious circle hyperglycaemia-insulin depletion-hyperglycaemia and lead to frequent and sustained remissions of juvenile diabetes.     

C肽在糖尿病慢性并发症发生和发展中的作用及其机制

近年来的研究显示,C肽能够特异性地结合到细胞表而,通过多种机制在糖尿病慢性并发症的发生发展中起着重要作用,如C肽可以减轻肾脏的高滤过状态,减少高渗性利尿和白蛋白渗出,改善糖尿病患者的微循环,增加患者的心功能,预防和逆转神经病变.本文综述了 C肽在糖尿病并发症发生和发展中的作用及其机制.     

B-cell function and blood glucose control in insulin dependent diabetics within the first month of insulin treatment

Summary Seventeen insulin dependent diabetics were studied after two to four weeks of insulin treatment in a situation approximating to their normal daily life. Some endogenous insulin secretion, assessed by plasma C-peptide determinations, was present in all. Plasma C-peptide concentration was positively correlated with the blood glucose concentration and increased after breakfast, lunch and dinner (p<0.01); both peak values and relative increases were lower than those observed in normal subjects (p<0.01). The highest insulin secretory capacity was found in subjects with the least unstable blood glucose concentration (r=0.57, p <0.03), and these patients required the smallest insulin doses (r=0.54, P<0.04). These findings demonstrate the metabolic importance of a preserved B-cell function.     

The rise and fall of insulin secretion in type 1 diabetes mellitus

An understanding of the natural history of beta cell responses is an essential prerequisite for interventional studies designed to prevent or treat type 1 diabetes. Here we review published data on changes in insulin responses in humans with type 1 diabetes. We also describe a new analysis of C-peptide responses in subjects who are at risk of type 1 diabetes and enrolled in the Diabetes Prevention Trial-1 (DPT-1). C-peptide responses to a mixed meal increase during childhood and through adolescence, but show no significant change during adult life; responses are lower in adults who progress to diabetes than in those who do not. The age-related increase in C-peptide responses may account for the higher levels of C-peptide observed in adults with newly diagnosed type 1 diabetes compared withhose in children and adolescents. Based on these findings, we propose a revised model of the natural history of the disease, in which an age-related increase in functional beta cell responses before the onset of autoimmune beta cell damage is an important determinant of the clinical features of the disease. Electronic Supplementary Material Supplementary material is available for this article at     

The role of ranitidine infusion on glucose,insulin and C-peptide serum levels induced by oral glucose tolerance test in healthy subjects

Summary In 9 healthy subjects we evaluated the effect of a constant ranitidine infusion (100 mg) on glucose (mg/dl), insulin (μU/ml) and C-peptide (ng/ml) serum levels promoted by oral glucose tolerance test (75 g). Ranitidine significantly increased the area under concentration/time curves for glucose and insulin but not that of C-peptide. Our data indicate that ranitidine does not affect pancreatic insulin release nor peripheral glucose utilization and are consistent with the hypothesis that ranitidine influences the hepatic clearance of glucose and insulin both of which undergo high first-pass liver extraction.     

Evaluation of B-cell secretion and peripheral insulin resistance during pregnancy and after delivery in gestational diabetes mellitus with obesity

Summary Nine pregnant women with gestational diabetes mellitus (GDM) were studied. Six normal pregnant women and six normal nonpregnant women were evaluated as control groups. All the women underwent oral glucose tolerance test and glucose clamp during the third trimester of pregnancy and two months after delivery. During OGTT, glucose, C-peptide and insulin plasma levels were determined. C-peptide and insulin values in the late phase of OGTT were higher during pregancy than after delivery in both groups. In gestational diabetic women, the M-value in the second steady-state during glucose clamp was lower than in controls, both during pregnancy and after delivery. Nevertheless, in both groups the M-value during pregnancy was lower than after delivery. Moreover, in gestational diabetic women there was an inverse correlation between M-value in the second steady-state and ponderal excess index after delivery. In conclusion, the impaired peripheral glucose utilization and the pancreatic pattern of gestational diabetic women compared to normals suggested altered B-cell secretion response, increased peripheral resistance and overweight to be the main changes in GDM.     

Serum C-peptide as a key contributor to lipid-related residual cardiovascular risk in the elderly

ObjectivesThe serum levels of C-peptide, an important risk factor for cardiovascular disease (CVD), increase with age. This study aimed to investigate the association between serum C-peptide and increased risk for CVD with altered lipid metabolism in the elderly.MethodsThis was a population-based cross-sectional study that included 3091 elderly participants aged ≥65 years. Serum C-peptide and lipid levels were measured according to standard protocols. Sampling weights were used to estimate the characteristics of study participants. Stratified analysis of covariance was used to evaluate the changes in the serum lipid levels according to quartiles of serum C-peptide levels, and the linear trend was assessed using a linear model. The logistic regression model was carried out to determine the association between the serum C-peptide levels and serum lipid levels.ResultsThe results of the analysis of covariance stratified by sex and serum insulin level showed that the serum triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels were significantly associated with changes in the serum C-peptide levels, independent of the serum insulin level. The logistic regression analyses indicated that the serum C-peptide levels were positively associated with the serum TG levels, and negatively associated with the serum HDL-C levels. A significant dose-response association was obtained in both men and women.ConclusionsSerum C-peptide levels were strongly associated with increased serum TG and reduced HDL-C levels in the elderly. Our results suggest that serum C-peptide increases the risk of CVD via a pathway that increases TG or decreases HDL-C levels.