糖尿病大鼠小肠Cajal间质细胞及干细胞因子的变化及半夏泻心汤的干预作用

[目的]观察糖尿病（diabetes mellitus,DM）大鼠小肠Cajal间质细胞（ICC）及干细胞因子（stem cell faetor,SCF）表达的变化及半夏泻心汤的干预作用。[方法]除10只大鼠作为正常组外,其他大鼠采用腹腔注射STZ复制DM模型后随机分为DM组、半夏泻心汤组及西药组。半固体营养糊灌胃测定各组大鼠小肠推进率,免疫组化检测c-Kit及SCF在小肠组织中的表达;Western blot检测小肠组织c-Kit蛋白、SCF蛋白表达。[结果]半夏泻心汤组与西药组大鼠的体质量、小肠推进率、c-Kit及SCF阳性细胞数、c-Kit蛋白及SCF蛋白的表达均较DM组明显增加（均P〈o．05）;半夏泻心汤组与西药组大鼠的血糖值较DM组明显降低（P〈0．05）。半夏泻心汤组与西药组之间差异无统计学意义（均P〉0．05）。[结论]半夏泻心汤可以促进DM大鼠小肠肌间神经丛c-Kit、SCF的表达,提示对受损的DM大鼠小肠ICC、SCF有部分恢复作用,从而对DM大鼠的小肠动力障碍有一定的改善作用。     

糖尿病血管内皮细胞代谢改变的研究进展

血管内皮细胞功能障碍是糖尿病（DM）血管并发症的始动环节。高血糖所致的氧化应激水平升高、异常糖代谢途径激活、晚期糖基化终产物（AGEs）累积和蛋白激酶C（PKC）通路活化等代谢改变均可介导内皮细胞损伤。如何抑制内皮细胞异常代谢并改善内皮细胞功能一直是DM血管并发症的研究重点。本文主要就DM患者血管内皮细胞的代谢改变作一综述。     

血尿酸与2型糖尿病患者周围神经病变的相关性研究

目的：探讨血清尿酸（SUA）水平与2型糖尿病（T2DM）患者糖尿病周围神经并发症（DPN）的关系。方法选取2011年3月至2013年3月在首都医科大学附属复兴医院内分泌科住院及门诊就诊的T2DM患者920例。采集血清进行生化指标[空腹血糖（FBG）,糖化血红蛋白（HbA1c）,总胆固醇（TC）,甘油三酯（TG）,低密度脂蛋白胆固醇（LDL-C）,高密度脂蛋白胆固醇（HDL-C）,SUA]检测,同时对入组患者是否患有DPN进行诊断并记录。SUA水平四分位法分为4个水平,logistic回归分析不同尿酸水平与DPN发病率的关系。结果 logistic回归分析结果显示SUA水平＞3.5mg/dl即第2个四分位后,SUA即为DPN的危险因素,且随着SUA水平的升高,其影响程度增加,OR值分别为2.95（2.02～8.76）,3.06（1.75～6.45）,4.15（0.84～6.74）,均P＜0.05。结论 SUA是DPN的一个危险因素,在DPN的临床治疗中除了降糖、降脂和降压之外,有效地降低SUA水平应该成为治疗中的一个重要环节。     

Effects of Lizhong Tang on cultured mouse small intestine interstitial cells of Cajal

AIM:To investigate the effects of Lizhong Tang,an herbal product used in traditional Chinese medicine,on mouse small intestine interstitial cells of Cajal(ICCs).METHODS:Enzymatic digestions were used to dissociate ICCs from mouse small intestine tissues.The ICCs were morphologically distinct from other cell types in culture and were identified using phase contrast microscopy after verification with anti c-kit antibody.A whole-cell patch-clamp configuration was used to record potentials(current clamp) from cultured ICCs.All of the experiments were performed at 30-32 ℃.RESULTS:ICCs generated pacemaker potentials,and Lizhong Tang produced membrane depolarization in current-clamp mode.The application of flufenamic acid(a nonselective cation channel blocker) abolished the generation of pacemaker potentials by Lizhong Tang.Pretreatment with thapsigargin(a Ca 2+-ATPase inhibi-tor in the endoplasmic reticulum) also abolished the generation of pacemaker potentials by Lizhong Tang.However,pacemaker potentials were completely abolished in the presence of an external Ca 2+-free solution,and under this condition,Lizhong Tang induced membrane depolarizations.Furthermore,When GDPβ-S(1 mmol/L) was in the pipette solution,Lizhong Tang still induced membrane depolarizations.In addition,membrane depolarizations were not inhibited by chelerythrine or calphostin C,which are protein kinase C inhibitors,but were inhibited by U-73122,an active phospholipase C inhibitors.CONCLUSION:These results suggest that Lizhong Tang might affect gastrointestinal motility by modulating pacemaker activity in interstitial cells of Cajal.     

Evolution of cardiac changes in young insulin-dependent (type 1) diabetic patients—one more piece of the puzzle of diabetic cardiopathy

Based on our recent reports that increased myocardial contractility has been found in newly diagnosed diabetic patients, and that diastolic (D) dysfunction precedes systolic (S) dysfunction, we suggested that the development of diabetic cardiopathy passes through the following stages: (I) increased myocardial contractility, (II) intact S and D function, (III) intact S function and D dysfunction, and (IV) S and D dysfunction. The aim of this pilot study was to test this hypothesis. One hundred fifty-seven young (26.2 ± 7.4 years) cardiac-asymptomatic patients with type 1 diabetes and 54 healthy subjects were studied using M-mode echocardiography. The presence of at least one of the variables for systolic function (ejection fraction, mean velocity of circumference, fiber shortening, and stroke index) or diastolic function [left atrium emptying index (LAEI), EFo slope of anterior mitral leaflet, and isovolu-metric relaxation time (IRT)] outside the control mean ± 2 SD was interpreted as an increased or depressed myocardial contractility, and diastolic dysfunction, respectively. The severity of diabetic complications (retinopathy, nephropathy, and cardiac autonomic neuropathy) was evaluated by the diabetic complication index (DCI=0 + 6 scores). Our hypothesis was confirmed significantly (p< 0.001) in 148 (94%) patients with diabetes. Duration of diabetes and DCI progressed significantly (ANOVA: F = 36.6, p<0.001; F=70.8, p<0.001) with hypothetical stages. Diastolic dysfunction was more pronounced in stage IV than in stage HI: IRT (80.5 ± 18.6 ms vs. 62.5 ± 16.4, p<0.001), EFo (63 ± 15 mm/s vs. 72 ± 21, p<0.05), LAEI (0.58 ± 0.13 vs. 0.8 ± 0.15, p < 0.001). End-diastolic volume/LV muscle mass ratio was reduced in stage III (0.73 ±0.16 ml/g) compared with the control value (0.83 ± 0.17, p < 0.01), but was higher than that in stage IV (0.65 ± 0.16, p < 0.05). The left atrium in stage HI (18.2 ± 3.7 mm/m²) was dilated compared with the control value (16.2 ± 3.3, p < 0.01) and more dilated in stage IV (19.6 ± 3.1, p<0.001). The present study demonstrates the following stage development of specific diabetic cardiac changes: (I) increased myocardial contractility; (II) intact S and D function; (III) initial D dysfunction, LV restriction and LA dilation with normal S function; and (IV) progression of the previous changes and appearance of S dysfunction.     

锌原卟啉对糖尿病大鼠结肠动力及Cajal细胞的影响

目的 探讨血红素氧合酶(HO)阻滞剂锌原卟啉(ZnPP)对糖尿病(DM)大鼠结肠动力和Cajal间质细胞(ICC)的影响.方法 雄性SD大鼠腹腔注射链脲佐菌素(STZ),3 d后选取成功造模大鼠24只作为DM组,另取正常大鼠16只作为对照组.饲养6周时,选取DM组大鼠和对照组大鼠各8只,行碳末推进实验,确认有无胃肠动力障碍.剩余DM组大鼠第6周起予以干预,DM未干预组(8只)0.1 mol/L磷酸盐缓冲液腹腔注射,隔日1次,连续3周;DM+ZnPP组(8只),ZnPP 10 μmol/kg腹腔注射,隔日1次,连续3周.对照组(8只)予以膜腔注射0.1 mmol/L磷酸盐缓冲液.Western印迹法检测结肠组织HO-1、HO-2和c-kit表达.免疫组化法测定结肠组织HO-1、HO-2和c-kit阳性细胞面积.结果 DM未干预组胃肠推进指数为(63.0±1.2)%,较对照组显著减低[(71.85:2.0)%,P<0.05];而DM+ZnPP组胃肠推进指数为(72.5±2.6)%,较DM未干预组明显改善(P<0.05),且与对照组差异无统计学意义(P>0.05).DM+ZnPP组近、远端结肠HO-1表达明显下降(P<0.05).DM未干预组和DM+ZnPP组近端结肠HO-2表达均较对照组显著减少(P<0.05).DM未干预组近、远端结肠组织c-kit较对照组显著减少(P<0.05);DM+ZnPP组c-kit的表达较DM未干预组明显改善(P<0.05),且与对照组间差异无统计学意义(P>0.05).结论 ZnPP可能通过阻滞HO-1对DM大鼠结肠Cajal间质细胞有保护作用,并改善其结肠动力障碍.     

The activity of calpains in lymphocytes is glucose-dependent and is decreased in diabetic patients

Calpains are nonlysosomal calcium-dependent cysteine proteases that participate in insulin secretion and action. Polymorphisms in the calpain-10 gene have been shown to increase the risk for type 2 diabetes. Since white blood cells have been used to study glucose homeostasis, the present study was carried to find out if calpains have different activity and/or expression in accessible cells such as lymphocytes of individuals with or without type 2 diabetes. Fasting blood glucose concentration was significantly higher in diabetic subjects, whereas the difference in the activity of calpains evaluated in basal and stimulating extracellular glucose concentration was significantly higher in the lymphocytes from the control group. The mRNA expression of calpain-10 was similar in the lymphocytes of both patients and controls. The protein blots showed four bands that ranged between 75 and 50 kDa; however, no statistical differences were observed in the expression of the calpain-10 isoforms between controls and patients. Data obtained showed that human lymphocytes express calpain-10 mRNA and protein, showing a similar expression between diabetic and control subjects, nevertheless in the diabetic group calpain activity was less glucose-sensitive.     

Lack of both bradykinin B1 and B2 receptors enhances nephropathy,neuropathy, and bone mineral loss in Akita diabetic mice

An insertion polymorphism of the angiotensin-I converting enzyme gene (ACE) is common in humans and the higher expressing allele is associated with an increased risk of diabetic complications. The ACE polymorphism does not significantly affect blood pressure or angiotensin II levels, suggesting that the kallikrein-kinin system partly mediates the effects of the polymorphism. We have therefore explored the influence of lack of both bradykinin receptors (B1R and B2R) on diabetic nephropathy, neuropathy, and osteopathy in male mice heterozygous for the Akita diabetogenic mutation in the insulin 2 gene (Ins2). We find that all of the detrimental phenotypes observed in Akita diabetes are enhanced by lack of both B1R and B2R, including urinary albumin excretion, glomerulosclerosis, glomerular basement membrane thickening, mitochondrial DNA deletions, reduction of nerve conduction velocities and of heat sensation, and bone mineral loss. Absence of the bradykinin receptors also enhances the diabetes-associated increases in plasma thiobarbituric acid-reactive substances, mitochondrial DNA deletions, and renal expression of fibrogenic genes, including transforming growth factor beta1, connective tissue growth factor, and endothelin-1. Thus, lack of B1R and B2R exacerbates diabetic complications. The enhanced renal injury in diabetic mice caused by lack of B1R and B2R may be mediated by a combination of increases in oxidative stress, mitochondrial DNA damage and over expression of fibrogenic genes.     

老年糖尿病足坏疽患者的临床特征及其危险因素分析

目的了解老年人糖尿病足坏疽（ＤＦ）的临床特征及其危险因素。方法对２２１例老年和１６３例老年前期ＤＦ的患病率、各种诱因的百分比、ＤＦ和非ＤＦ患者胫后感觉神经传导速度、双下肢动脉管径和血流量等检测结果进行分析。结果（１）老年和老年前期ＤＦ患者的患病率（４９．５％和２７．４％）明显高于青中年组（１１．０％）；自发性溃疡、水疱破裂、穿鞋不当摩擦伤为ＤＦ的常见诱因；湿性坏疽为ＤＦ的主要类型。（２）老年和老年前期ＤＦ患者因周围神经病变致传导速度检测不能引出波形者分别占９２％和８２％、周围血管病变致动脉狭窄和闭塞者分别占９２％和７８％，显著高于非ＤＦ组。结论老年人糖尿病易合并ＤＦ；周围神经病变和周围血管病变在ＤＦ的发生和发展中起重要作用。     

Diabetic neuropathic cachexia and acute bilateral cataract formation following rapid glycaemic control in a newly diagnosed type 1 diabetic patient.

In patients with Type 1 diabetes mellitus (DM), the development of complications within the first few years of diagnosis is very unusual and the development of complications within weeks of commencement of insulin therapy is exceptional. Diabetic neuropathic cachexia, unlike the other more common neuropathies associated with diabetes, is a rare form of peripheral neuropathy characterized by profound weight loss, painful dysaesthesias over the limbs and trunk with spontaneous resolution usually occurring within a year. The morphologically distinct diabetic or metabolic cataract in patients with newly diagnosed Type 1 DM is also a rare complication. We describe the first case of a young man with newly diagnosed Type 1 DM who developed these two rare complications within 3 months of diagnosis and insulin therapy commencement. Rapid development of complications in this patient raises two possibilities, i.e. a probable link between the pathophysiology of these two complications following rapid glycaemic control, and a subset of patients with unusual susceptibility to complications. We re-emphasize the need for vigilant monitoring of complications in young diabetic patients, even in the first few years of their disease. In particular, young patients with visual impairment should be evaluated carefully for evidence of treatable eye complications.     

糖尿病小鼠缺血诱导的骨髓内皮祖细胞动员障碍

目的 观察糖尿病动物缺血诱导的骨髓内皮祖细胞（EPC）动员是否存在障碍,以及这种障碍是否和缺血诱导的血管内皮生长因子（VEGF）释放降低有关。方法 链脲霉素40mg／kg诱导C5781／6雄鼠糖尿病,非糖尿病组给予等量缓冲液。饲养2个月后,进行左侧股动脉高位结扎离断术造成后肢缺血模型,通过红四氮唑染色法与后肢血管造影确定造模成功。于术前及术后不同时间点采血（1天,3天,n：8;5天,7天及14天,n=5）,三色流式细胞术检测两组动物外周血单个核细胞中c-Ki^＋／Sea-1^＋／flk-1^＋早期EPC比例。ELISA法测定相应时间点血浆VEGF水平。结果 基础状态下,糖尿病组循环EPC数量较非糖尿病组明显减少[（0．60±0．03）％比（0．95±0．09）％,P〈0．001],血浆VEGF水平低于试剂盒检测灵敏度。两组动物缺血诱导的骨髓早期EPC释放曲线相似,即术后1天显著增加,术后3天达峰,动员持续至2周以上。但是在EPC早期快速动员阶段（术后前3天）,糖尿病组外周血早期EPC数量较非糖尿病组明显减少[1天,（1．16±0．29）％比（1．80±0．32）％,P〈0．05;3天,（1．38±0．34）％比（2．37±0．52）％,P〈0．05]。同时组织缺血也伴随着血浆VEGF浓度的显著增高：非糖尿病组血浆VEGF水平在术后一天快速增加并达到峰值,此后渐降至相对较低水平持续两周以上;而糖尿病组术后1天血浆VEGF快速释放明显降低[（73．1±18．6）pg／ml比（128．5±44．2）Pg／ml,P〈0．05]。结论 糖尿病动物基础状态下外周血早期EPC数量减少,组织缺血诱导的骨髓EPC动员障碍,这种障碍可能与缺血诱导的VEGF释放减少有关。     

The annual incidence of diabetic complications in a population of patients with Type 1 and Type 2 diabetes.

AIM: The DARTS diabetes register was used to determine incidence rates of diabetes and related complications in 1997. METHODS: The diabetes register records detailed clinical information for all patients diagnosed with diabetes in Tayside, Scotland. The study population included patients who were alive and registered with a Tayside GP for the duration of 1997 or who died in Tayside during this time. Patients who had diabetes prior to 1997, those who developed diabetes in 1997, and those who developed diabetic complications in 1997, were identified. RESULTS: In the Tayside population of 385 774 at the start of 1997, there were 942 and 6632 patients with Type 1 and Type 2 diabetes, with a further 29 and 744 patients diagnosed in 1997. The incidence rates (with 95% confidence intervals) of diabetic complications per 1000 patients with Type 1 and Type 2 diabetes, respectively, were: angina 8.8 (4.5-17.3) and 38.4 (33.4-44.2); myocardial infarction 8.6 (4.4-16.9) and 21.9 (18.4-25.9); cerebrovascular accident 1.1 (0.3-6.0) and 14.2 (11.6-17.5); lower extremity amputation 3.2 (1.2-9.4) and 3.1 (2.1-4.8); peripheral vascular disease 5.5 (2.4-12.8) and 13.6 (11.0-16.8); registered blindness 1.1 (0.3-5.9) and 1.6 (0.9-2.9); end-stage renal failure 6.4 (3.0-13.8) and 5.0 (3.6-7.0). Mortality was 14.6 per 1000 (9.6-25.7) in Type 1 diabetes and 50.0 per 1000 (45.1-55.3) in Type 2 diabetes. CONCLUSION: This study provides baseline figures for rates of diabetic complications for Type 1 and Type 2 diabetes, and confirms the increased burden of macrovascular disease in Type 2 diabetes.     

Critical review of oral drug treatments for diabetic neuropathic pain-clinical outcomes based on efficacy and safety data from placebo-controlled and direct comparative studies

The present review aims to evaluate the efficacy and safety of a selection of oral treatments for the management of painful diabetic neuropathy. A literature review was conducted retrieving placebo-controlled and direct comparative studies with a selection of oral treatments for painful diabetic neuropathy. All studies were analyzed with regard to efficacy and tolerability. Efficacy was evaluated as the percentage improvement in pain intensity between baseline and endpoint. Tolerability was evaluated by means of study discontinuations due to adverse events and by incidence of drug-related adverse events.The analyzed trials enrolled different patient populations with mostly small numbers of patients. The great variability in dosages and dose titration schemes, cross-over designs with variable wash-out periods, and other design schemes made comparison between the different studies difficult. Gabapentin, lamotrigine, tramadol, oxycodone, mexiletine, and acetyl-L-carnitine were the only treatments studied in large (at least 100 patients), placebo-controlled parallel group trials.It is concluded that standardization in design and reporting for comparison of treatments is needed. Validated questionnaires for evaluation of the efficacy and safety should be further developed. Based on the reviewed randomised controlled trials, gabapentin shows good efficacy, a favourable side-effect profile with lack of drug interactions and therefore it may be a first choice treatment in painful diabetic neuropathy, especially in the elderly. However, head to head trials of current treatments are lacking and therefore randomized controlled trials are required to address this issue.     

糖尿病结肠动力障碍大鼠结肠Cajal间质细胞凋亡和间隙连接蛋白43的表达

目的 探讨糖尿病结肠动力障碍大鼠结肠Cajal间质细胞(ICC)的凋亡及ICC的间隙连接蛋白43(Cx43)表达的变化在结肠动力障碍发生中的意义.方法 雄性Sprague-Dawley(SD)大鼠36只,根据体质量及血糖按随机数字表法分为正常6周组、正常10周组、糖尿病6周组、糖尿病10周组,每组9只.腹腔注射链脲佐菌素建立糖尿病模型,检测体质量、空腹血糖及胃肠推进率;HE染色观察ICC;TUNEL法检测ICC的凋亡指数;免疫组化检测ICC的c-Kit、Cx43蛋白表达.结果 (1)糖尿病组较同时间点正常组体质量下降,空腹血糖升高,胃肠推进率降低,ICC的c-Kit、Cx43蛋白表达降低(F=76.68,1397.24,18.87,137.65,87.73,P均＜0.05).(2)糖尿病10周组较糖尿病6周组空腹血糖升高,胃肠推进率降低,ICC的c-Kit、Cx43蛋白表达降低(F=76.68,1397.24,18.87,137.65,87.73,P均＜0.05).(3)糖尿病组ICC的凋亡指数与同时间点正常组相比,差异无统计学意义;糖尿病10周组与糖尿病6周组ICC的凋亡指数差异也无统计学意义(P均＞0.05).结论 ICC数量减少、Cx43蛋白表达降低可能是糖尿病结肠动力障碍的发生机制之一,且上述改变随病程发展而加重;ICC数量减少可能与ICC凋亡无关.     

Autonomic neuropathy in Type 2 diabetic patients is associated with hyperinsulinaemia and hypertriglyceridaemia.

AIMS: To clarify whether parasympathetic neuropathy in Type 2 diabetic patients is associated with features of the insulin resistance syndrome. METHODS: Blood pressures, glycaemic control (HbA1c), plasma lipids, residual beta-cell function (fasting plasma C-peptide), autonomic nerve function, urinary albumin excretion and glomerular filtration rate (Cr-EDTA clearance) were evaluated in 82 Type 2 diabetic patients (age 63+/-years) 5 years after diagnosis of diabetes. RESULTS: Parasympathetic neuropathy (an abnormal age corrected E/I ratio) was found in 24/82 (29%) patients. After adjustment for body mass index (BMI), patients with parasympathetic neuropathy had elevated fasting plasma C-peptide (P < 0.001) and triglyceride (Tg) (P < 0.05) levels compared with patients without parasympathetic neuropathy. In addition, the age corrected E/I ratio correlated inversely with Tg (r=-0.31; P<0.01) and fasting plasma C-peptide (r=-0.32; P < 0.01) in the Type 2 diabetic patients. CONCLUSION: Autonomic neuropathy 5 years after diagnosis of Type 2 diabetes is associated with an unfavourable metabolic risk profile.     

Recruitment of bone marrow-derived valve interstitial cells is a normal homeostatic process

Advances in understanding of the maintenance of the cardiac valves during normal cardiac function and response to injury have led to several novel findings, including that there is contribution of extra-cardiac cells to the major cellular population of the valve: the valve interstitial cell (VIC). While suggested to occur in human heart studies, we have been able to experimentally demonstrate, using a mouse model, that cells of bone marrow hematopoietic stem cell origin engraft into the valves and synthesize collagen type I. Based on these initial findings, we sought to further characterize this cell population in terms of its similarity to VICs and begin to elucidate its contribution to valve homeostasis. To accomplish this, chimeric mice whose bone marrow was repopulated with enhanced green fluorescent protein (EGFP) expressing total nucleated bone marrow cells were used to establish a profile of EGFP⁺ valve cells in terms of their expression of hematopoietic antigens, progenitor markers, fibroblast- and myofibroblast-related molecules, as well as their distribution within the valves. Using this profile, we show that normal (non-irradiated, non-transplanted) mice have BM-derived cell populations that exhibit identical morphology and phenotype to those observed in transplanted mice. Collectively, our findings establish that the engraftment of bone marrow-derived cells occurs as part of normal valve homeostasis. Further, our efforts demonstrate that the use of myeloablative irradiation, which is commonly employed in studies involving bone marrow transplantation, does not elicit changes in the bone marrow-derived VIC phenotype in recipient mice.     

A deficiency of gastric interstitial cells of Cajal accompanied by decreased expression of neuronal nitric oxide synthase and substance P in patients with type 2 diabetes mellitus

Background Gastrointestinal motility is impaired in patients with diabetes mellitus (DM). Interstitial cells of Cajal (ICC) in the gastrointestinal tract play a central role in gastrointestinal motility. The present study examined whether ICC density, or expression of neuronal nitric oxide synthase (nNOS)- and substance P (SP)-containing nerves in the gastric antrum, were altered in patients with type 2 DM. Methods Paraffin-embedded gastric specimens from 51 controls and 36 male DM patients with gastric cancer were used for immunohistochemistry. Serial sections were stained with Kit and mast cell tryptase-specific antibodies. Fresh-frozen gastric specimens from patients with gastric cancer were used for immunofluorescence. The specimens were stained with antibodies to Kit, nNOS, and SP, and levels of expression of these three markers were compared between controls and DM patients. Results ICC density in the inner circular muscle layer, but not in the myenteric plexus, was lower in patients with severe DM than in controls in paraffin-embedded specimens. In addition, decreased expression of nNOS and SP accompanied by reduced ICC density was observed in frozen specimens from patients with DM. Conclusions These results suggest that lower gastric ICC, nNOS, and SP densities in patients with DM may be associated with the pathogenesis of diabetic gastroparesis.     

Glycaemic variability and complications in patients with diabetes mellitus: evidence from a systematic review of the literature

Aim: The objective of this review was to assess the published evidence for an association between glycaemic variability and the development of chronic micro‐ and macrovascular complications in patients with diabetes mellitus (DM). Methods: A systematic review of English‐language literature published from January 1990 through November 2008 was performed. Interventional and observational studies in patients with type 1 or type 2 DM reporting a measure of glycaemic variability and its impact on the development or progression of micro‐ and macrovascular diabetic complications were assessed. Results: A total of 18 studies ?8 on type 1 DM and 10 on type 2 DM patients–meeting the inclusion criteria were identified. Studies in patients with type 1 DM revealed that glucose variability has little impact on the development of diabetic complications. Only in two of the eight type 1 DM studies did glucose variability have a significant association with microvascular complications, but not with macrovascular complications. Among type 2 DM studies, a significant positive association between glucose variability and the development or progression of diabetic retinopathy, cardiovascular events and mortality was reported in 9 of 10 studies. Only one type 2 DM study reported no association between glucose variability and progression of retinopathy. Conclusions: Based on this overview of the available evidence, there appears to be a signal suggesting that glucose variability, characterized by extreme glucose excursions, could be a predictor of diabetic complications, independent of HbA1c levels, in patients with type 2 DM. Better daily control of blood glucose excursions, especially in the postprandial period, may reduce the risk of these complications. Future prospective trials evaluating and comparing the effect of the control of glycaemic variability on the development of diabetic micro‐ and macrovascular complications are needed to further strengthen the evidence base.