Circulating endothelial cells are elevated in patients with type 2 diabetes mellitus independently of HbA1c

Aims/hypothesis Patients with diabetes mellitus are well known to be at high risk for vascular disease. Circulating endothelial cells (CECs) have been reported to be an ex vivo indicator of vascular injury. We investigated the presence of CECs in the peripheral blood of 25 patients with diabetes mellitus and in nine non-diabetic control donors.Methods Endothelial cells were isolated from peripheral blood with anti-CD-146–coated immunomagnetic Dynabeads, and were stained with acridine orange dye and counted by fluorescence microscopy. The cells were also stained for von Willebrand factor and Ulex europaeus lectin 1.Results Patients with diabetes mellitus had an elevated number of CECs (mean 69±30 cells/ml, range 35–126) compared with healthy controls (mean 10±5 cells/ml, range 3–18) (p<0.001). The increase in CECs did not correlate with the levels of HbA₁c. Circulating endothelial cell numbers were elevated regardless of glucose levels, suggesting that, even with control of glucose levels, there is increased endothelial cell sloughing.Conclusions Our study suggests that the higher number of CECs in patients with type 2 diabetes may reflect ongoing vascular injury that is not directly dependent on glucose control.     

Endothelial progenitor cells and peripheral neuropathy in subjects with type 2 diabetes mellitus

AimsTo examine for differences in circulating progenitor cells (CPCs) and endothelial progenitor cells (EPCs) in patients with and without diabetic peripheral neuropathy (DPN).MethodsA total of 105 participants were included: 50 patients with type 2 diabetes (T2DM) and DPN, 30 patients with T2DM without DPN and 25 healthy individuals. CPCs and 6 different EPCs phenotypes were assessed with flow cytometry. We also measured plasma levels of vascular endothelial growth factor (VEGF), stromal cell-derived factor 1 (SDF-1), vascular cell adhesion protein-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM) and tumor necrosis factor a (TNFa).ResultsNo difference was observed in the number of CPCs among the 3 groups. Patients with DPN had higher numbers of all 6 EPCs phenotypes when compared with patients without DPN and higher number of 5 EPCs phenotypes when compared with healthy individuals. Plasma VEFG, VCAM-1, ICAM-1 and TNFa levels did not differ among the 3 groups. Patients with DPN had lower SDF-1 levels in comparison with healthy individuals.ConclusionCirculating EPCs are increased while SDF-1 levels are decreased in the presence of DPN. Our findings suggest that DPN may be associated with impaired trafficking of EPCs and impaired EPCs homing to the injured endothelium.     

Circulating osteogenic precursor cells in type 2 diabetes mellitus

Context: Type 2 diabetes mellitus (T2D) is associated with an increased risk of fractures and low bone formation. However, the mechanism for the low bone formation is not well understood. Recently, circulating osteogenic precursor (COP) cells, which contribute to bone formation, have been characterized in the peripheral circulation. Objective: Our objective was to characterize the number and maturity of COP cells in T2D. Patients, Design, and Setting: Eighteen postmenopausal women with T2D and 27 controls participated in this cross-sectional study at a clinical research center. Main Outcome Measures: COP cells were characterized using flow cytometry and antibodies against osteocalcin (OCN) and early stem cell markers. Histomorphometric (n = 9) and molecular (n=14) indices of bone turnover and oxidative stress were also measured. Results: The percentage of OCN(+) cells in peripheral blood mononuclear cells was lower in T2D (0.8 ± 0.2 vs. 1.6 ± 0.4%; P < 0.0001), whereas the percentage of OCN(+) cells coexpressing the early marker CD146 was increased (OCN(+)/CD146(+): 33.3 ± 7 vs. 12.0 ± 4%; P < 0.0001). Reduced histomorphometric indices of bone formation were observed in T2D subjects, including mineralizing surface (2.65 ± 1.9 vs. 7.58 ± 2.4%, P = 0.02), bone formation rate (0.01 ± 0.1 vs. 0.05 ±0.2 μm(3)/um(2) · d, P = 0.02), and osteoblast surface (1.23 ±0.9 vs. 4.60 ± 2.5%, P = 0.03). T2D subjects also had reduced molecular expression of the osteoblast regulator gene Runx2 but increased expression of the oxidative stress markers p66(Shc) and SOD2. Conclusions: Circulating OCN(+) cells were decreased in T2D, whereas OCN(+)/CD146(+) cells were increased. Histomorphometric indices of bone formation were decreased in T2D, as was molecular expression of osteoblastic activity. Stimulation of bone formation may have beneficial therapeutic skeletal consequences in T2D.     

Circulating endothelial progenitor cells are reduced in SLE in the absence of coronary artery calcification

Circulating endothelial progenitor cells (EPCs) are reduced in patients with systemic lupus erythematosus (SLE). A reduced number of EPCs are associated with the presence of atherosclerosis in other populations. We sought to determine whether the reduction in EPC numbers in SLE is dependent on the presence of advanced coronary artery calcification (CAC). Patients with SLE had previous coronary calcium scores which placed them in either the >75th percentile or <25th percentile for their age. Seventeen patients with SLE and 13 healthy controls (HC) were included in the study. White blood cells were stained for EPC and progenitor cell markers including CD34, CD133, and VEGFR and analyzed by flow cytometry. SLE patients had repeated coronary imaging as well as carotid ultrasound. There was no difference in age between groups. SLE patients with advanced CAC were more likely to be hypertensive, to be smokers, and to have longer disease duration than SLE patients without CAC. SLE patients without evidence of CAC had a significantly lower number of EPCs (CD34+/CD133+/VEGFR+) compared to HC (median (IQR)) 0 (0, 6.7) vs. 10.2 (5.8, 12.3) (P = 0.02). Total numbers of PCs (CD133+/CD34+) were not significantly decreased in patients with SLE ((mean ± SEM) 1,007 ± 154 vs. 824 ± 170 (P = 0.20)). No significant difference was seen in EPC number between SLE patients without CAC and those with advanced CAC. Increased carotid intima-media thickness did not correlate with CAC or EPC number in SLE patients. Reduced numbers of EPCs in SLE patients may be observed compared to HC even in the absence of CAC. Differences in measured risk factor profiles and depletion of total circulating PCs do not fully explain this finding.     

Circulating endothelial progenitor cell levels are not reduced in HIV-infected men

Reduced levels of endothelial progenitor cells (EPCs) have been associated with increased cardiovascular (CV) risk, but limited data are available on EPC levels in the human immunodeficiency virus (HIV)-infected population. EPCs (CD45(dim)/CD34(+)/kinase domain receptor(+)) from 36 HIV-uninfected and 30 antiretroviral therapy-naive HIV-infected men without known CV risk factors were enumerated using flow cytometry. The mean EPC levels (± standard error of the mean) were 1.4 ± 0.5 cells/μL in the HIV-infected group and 3.7 ± 2.2 cells/μL in the control group (P = .92). EPC levels were not associated with disease parameters, such as CD4 cell count or viral load. Reductions in EPC levels do not seem to explain the increased risk of CV disease among HIV-infected men.     

糖尿病周围血管病血管内皮祖细胞数量和功能的改变及其机制探讨

糖尿病合并周围血管病患者内皮祖细胞数目减少,并与糖化血红蛋白水平呈负相关;增殖与黏附功能减低。糖尿病周围血管病变的发生可能与内皮祖细胞表达CXCR4减弱有关。     

男性糖尿病患者外周血内皮祖细胞与血管病变关系的研究

目的探讨男性糖尿病（DM）患者血管病变与外周血内皮祖细胞（EPCs）数量及功能的关系。方法对15名健康者（NC组）、20例DM未合并血管病变者（DM组）、18例DM合并血管病变者（DVP组）及10例非糖尿病冠心病者（NDCHD组）采集空腹静脉血,分离并培养EPCs。应用流式细胞技术、M1vr法、Boyden小室法、黏附法对EPCs进行鉴定、计数,以及细胞增殖、迁移及黏附功能测定。结果（1）EPCs与HbA1c呈负相关（r=0.54,p=0．02）。（2）EPCs数量和增殖功能在NDCHD组〈DVP组〈DM组〈NC组（P〈0.05）。（3）EPCs迁移功能NDCHD组与DVP组间无差异,且两组均低于DM组,DM组又低于NC组（P〈0．05）;黏附功能四组间无差异。结论男性DM患者尤其是合并血管病变者,存在EPCs数量减少以及增殖、迁移功能下降,其与血管病变的发生发展相关。     

Circulating vascular endothelial growth factor in the normo- and/or microalbuminuric patients with type 2 diabetes mellitus

Relationship between serum vascular endothelial growth factor (VEGF) level and parameters of endothelial injury and/or dysfunction in patients with diabetes mellitus type 2 with or without microalbuminuria was investigated. Eighty-four diabetic patients were divided in two subgroups (42 each): normoalbuminuric (NAU) and microalbuminuric (MAU). Forty-two blood donors were in control group. Serum VEGF and plasma von Willebrand factor, soluble thrombomodulin, plasminogen activator inhibitor 1, thrombin-activatable fibrinolysis inhibitor (TAFI) and tissue plasminogen activator (t-PA) were measured using enzyme-linked immunosorbent assay in all subjects. VEGF was significantly higher in NAU compared to controls. The difference between MAU and controls was not statistically significant, but there was a trend toward significance. Only TAFI correlated with VEGF in MAU. An observed significant increase of serum VEGF level already in NAU suggests that serum VEGF could be a sensitive predictor of endothelial dysfunction in type 2 diabetes.     

Circulating plasma vascular endothelial growth factor and microvascular complications of type 1 diabetes mellitus: the influence of ACE inhibition.

AIMS: To determine whether circulating plasma vascular endothelial growth factor (VEGF) is elevated in the presence of diabetic microvascular complications, and whether the impact of angiotensin-converting enzyme (ACE) inhibitors on these complications can be accounted for by changes in circulating VEGF. METHODS: Samples (299/354 of those with retinal photographs) from the EUCLID placebo-controlled clinical trial of the ACE inhibitor lisinopril in mainly normoalbuminuric non-hypertensive Type 1 diabetic patients were used. Albumin excretion rate (AER) was measured 6 monthly. Geometric mean VEGF levels by baseline retinopathy status, change in retinopathy over 2 years, and by treatment with lisinopril were calculated. RESULTS: No significant correlation was observed between VEGF at baseline and age, diabetes duration, glycaemic control, blood pressure, smoking, fibrinogen and von Willebrand factor. Mean VEGF concentration at baseline was 11.5 (95% confidence interval 6.0--27.9) pg/ml in those without retinopathy, 12.9 (6.0--38.9) pg/ml in those with non-proliferative retinopathy, and 16.1 (8.1--33.5) pg/ml in those with proliferative retinopathy (P = 0.06 for trend). Baseline VEGF was 15.2 pg/ml in those who progressed by at least one level of retinopathy by 2 years compared to 11.8 pg/ml in those who did not (P = 0.3). VEGF levels were not altered by lisinopril treatment. Results were similar for AER. CONCLUSIONS: Circulating plasma VEGF concentration is not strongly correlated with risk factor status or microvascular disease in Type 1 diabetes, nor is it affected by ACE inhibition. Changes in circulating VEGF cannot account for the beneficial effect of ACE inhibition on retinopathy.     

Metabolic rate and vascular function are reduced in women with a family history of type 2 diabetes mellitus

Metabolic and vascular abnormalities have been found in individuals with type 2 diabetes mellitus (T2D). Family history is often associated with increased risk of the development of T2D. We sought to determine if young, sedentary, insulin-sensitive individuals with a family history of T2D (FH+) have a reduced resting energy expenditure (REE) and vascular endothelial function compared with individuals who have no family history of T2D (FH-). The REE was determined in 18 FH+ individuals and 15 FH- individuals using indirect open-circuit calorimetry. Vascular endothelial function was measured via flow-mediated dilation (FMD) of the brachial artery. C-reactive protein and interleukin-6 were also measured to look at vascular inflammation. Body composition was measured via bioelectrical impedance analysis to determine fat-free mass and fat mass for each individual. Insulin resistance was calculated using the homeostasis model assessment equation and fasting insulin and glucose concentrations. Subjects (n = 42) were approximately 26 years old and had normal fasting serum insulin or glucose concentrations. The REE normalized for body weight (kilocalories per day per kilogram body weight) was significantly reduced in the FH+ women compared with FH- women (P < .001) but not in the men. The FMD was significantly reduced (34.3%) in the FH+ group compared with the FH- in women (P = .002). However, no between-group difference in FMD was present in male subjects (P = .376). Young, healthy, insulin-sensitive women with a family history of T2D have reduced whole-body metabolic rate and vascular endothelial function compared with those with no family history of disease. These differences in whole-body metabolic rate and vascular endothelial function were not present in male subjects.     

Circulating haemopoietic and endothelial progenitor cells are decreased in COPD.

Circulating CD34+ cells are haemopoietic progenitors that may play a role in tissue repair. No data are available on circulating progenitors in chronic obstructive pulmonary disease (COPD). Circulating CD34+ cells were studied in 18 patients with moderate-to-severe COPD (age: mean+/-sd 68+/-8 yrs; forced expiratory volume in one second: 48+/-12% predicted) and 12 controls, at rest and after endurance exercise. Plasma concentrations of haematopoietic growth factors (FMS-like tyrosine kinase 3 (Flt3) ligand, kit ligand), markers of hypoxia (vascular endothelial growth factor (VEGF)) and stimulators of angiogenesis (VEGF, hepatocyte growth factor (HGF)) and markers of systemic inflammation (tumour necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8) were measured. Compared with the controls, the COPD patients showed a three-fold reduction in CD34+ cell counts (3.3+/-2.5 versus 10.3+/-4.2 cells.microL-1), and a 50% decrease in AC133+ cells. In the COPD patients, progenitor-derived haemopoietic and endothelial cell colonies were reduced by 30-50%. However, four COPD patients showed progenitor counts in the normal range associated with lower TNF-alpha levels. In the entire sample, CD34+ cell counts correlated with exercise capacity and severity of airflow obstruction. After endurance exercise, progenitor counts were unchanged, while plasma Flt3 ligand and VEGF only increased in the COPD patients. Plasma HGF levels were higher in the COPD patients compared with the controls and correlated inversely with the number of progenitor-derived colonies. In conclusion, circulating CD34+ cells and endothelial progenitors were decreased in chronic obstructive pulmonary disease patients and could be correlated with disease severity.     

白脂素与2型糖尿病及其血管并发症的研究进展

白脂素(asprosin)是一种新型葡萄糖调控蛋白激素,其主要由白色脂肪细胞合成分泌。Asprosin可通过增强胰岛素抵抗、调节胰岛素分泌、影响食欲参与糖脂代谢,从而调节血糖稳态。此外,研究发现Asprosin与糖尿病大血管并发症及糖尿病微血管并发症存在较多联系,但具体机制尚不清楚。深入探讨Asprosin与糖尿病及其...     

Multifactorial treatment increases endothelial progenitor cells in patients with type 2 diabetes

Aims/hypothesis  

Endothelial progenitor cells (EPC) augment vascular repair and neovascularisation. Patients with type 2 diabetes have reduced EPC and increased risk of cardiovascular disease (CVD), which is reduced by multifactorial intervention. Our aim, therefore, was to evaluate in type 2 diabetic patients whether the numbers of EPC derived from peripheral blood mononuclear cells is influenced by a multifactorial treatment strategy.     

Potential manipulation of endothelial progenitor cells in diabetes and its complications

Diabetes mellitus increases cardiovascular risk through its negative impact on vascular endothelium. Although glucotoxicity and lipotoxicity account for endothelial cell damage, endothelial repair is also affected by diabetes. Endothelial progenitor cells (EPCs) are involved in the maintenance of endothelial homoeostasis and in the process of new vessel formation. For these reasons, EPCs are thought to have a protective impact within the cardiovascular system. In addition, EPCs appear to modulate the functioning of other organs, providing neurotropic signals and promoting repair of the glomerular endothelium. The exact mechanisms by which EPCs provide cardiovascular protection are unknown and the definition of EPCs is not standardized. Notwithstanding these limitations, the literature consistently indicates that EPCs are altered in type 1 and type 2 diabetes and in virtually all diabetic complications. Moreover, experimental models suggest that EPC‐based therapies might help prevent or reverse the features of end‐organ complications. This identifies EPCs as having a novel pathogenic role in diabetes and being a potential therapeutic target. Several ways of favourably modulating EPCs have been identified, including lifestyle intervention, commonly used medications and cell‐based approaches. Herein, we provide a comprehensive overview of EPC pathophysiology and the potential for EPC modulation in diabetes.     

Circulating vascular endothelial growth factor is unaffected by acute hyperglycemia and hyperinsulinemia in type 1 diabetes mellitus

BACKGROUND: Circulating levels of vascular endothelial growth factor (VEGF) may predict microvascular complications in type 1 diabetes mellitus and are elevated when metabolic control is poor. We tested whether serum VEGF is influenced by prevailing glucose and insulin levels. METHODS: In 15 type 1 diabetic patients, serum VEGF, plasma von Willebrand factor antigen (vWF-Ag), and serum soluble intercellular adhesion molecule-1 (s-ICAM) levels were measured after 210 min of hyperglycemia (blood glucose target 12.0 mmol/l) and hyperinsulinemia (insulin infused at 120 mU/kg/h), alone and in combination. These were then compared with the levels obtained at the end of a 210-min normoglycemic (blood glucose target 5.0 mmol/l) standard insulin clamp (insulin infused at 30 mU/kg/h). RESULTS: VEGF (p>0.60) as well as vWF-AG (p>0.80) and s-ICAM (p>0.20) remained unchanged at the end of the three intervention periods. CONCLUSION: These findings suggest that no special precautions, in terms of concurrent measurement of glucose or timing of insulin administration, are necessary when interpreting circulating VEGF in this patient category.     

An association of serum vistafin level and number of circulating endothelial progenitor cells in type 2 diabetes mellitus patients

BackgroundThe decreased number and impaired functions of endothelial progenitor cells (EPCs) may associate with cardiovascular disease (CV) including atherosclerosis. However, the role of vistafin in regulation of angiogenic EPC subset maturation in T2DM patients without known atherosclerosis is still not fully understood.The aim of the studyTo investigate an association of serum vistafin level and number of circulating EPCs in T2DM patients beyond known CV disease.MethodsThis case–control observational investigation was evolved 54 subjects with T2DM and 35 healthy volunteers. The flow cytometry was used for predictably distinguishing cell subsets, which depend on expression of CD45, CD34, CD14, Tie-2, and VEGFR2. Biomarkers were measured at baseline of the study.ResultsAll T2DM patients were divided depending median of vistafin level (5.88 ng/mL) in to two cohorts with low vistafin level (<5.88 ng/mL; n = 29) and high vistafin level (≥5.88 ng/mL; n = 25) respectively. Logistic regression analysis has shown that visfatin, hs-CRP, age and BMI were the best variables in the prediction of EPC number labeled as CD14⁺CD309⁺ and CD14⁺CD309⁺Tie²⁺ cells. After adjustment of the model to age and BMI elevated visfatin level remained the best predictor for both CD14⁺CD309⁺ and CD14⁺CD309⁺Tie²⁺ EPCs (OR 0.92, 95% CI: 0.88–0.95; P = 0.001 and OR 0.90, 95% CI: 0.87–0.96; P = 0.001 respectively).ConclusionWe found that elevated level of vistafin was an independent predictor for declined numerous of non-classical EPCs labeled as CD14⁺CD309⁺ and CD14⁺CD309⁺Tie²⁺, whereas CD34⁺ subsets of EPCs did not associate with vistafin level in T2DM individuals.     

可溶性血管细胞黏附分子-1与2型糖尿病及其并发症的相关性研究

目的探讨血清可溶性血管细胞黏附分子-1(sVCAM-1)与2型糖尿病及其并发症的关系.方法采用酶联免疫吸附法测定61例合并高血压和微血管并发症的糖尿病患者及36例正常人血清中sVCAM-1水平.结果2型糖尿病患者的sVCAM-1水平[(973.25±73.38)μg/L]明显高于非糖尿病患者[(230.45±12.47)μg/L],P＜0.001.合并高血压患者sVCAM-1[(1263.99±87.00)μg/L]较微血管病变者[(726.57±95.40)μg/L]增高更明显(P＜0.001).结论sVCAM-1参与了糖尿病血管并发症的发生和发展.