Serum CXCL16 as a Novel Marker of Renal Injury in Type 2 Diabetes Mellitus

Background

Soluble C-X-C chemokine ligand 16 (CXCL16), a scavenger receptor for oxidized low density lipoprotein, has been shown to promote atherogenic effects in vivo and to predict long-term mortality in acute coronary syndrome. The aim of this study was to explore the association of circulating CXCL16 levels with diabetic subjects with and without renal disease.

Methodology/Principal Findings

One hundred twenty Chinese subjects, which included patients with type 2 diabetes mellitus (T2DM), diabetic nephropathy (DN), and CKD, as well as healthy controls, were enrolled in this study. Serum CXCL16 levels were examined by immunoassay and other clinical biochemical parameters were tested based on standard methods. Our results indicated that, HDL and LDL cholesterol levels are significantly different in DN but not in T2D patients in comparison with healthy subjects. On the other hand, Serum CXCL16 levels were significantly increased in DN subjects compared with age and gender matched healthy and T2DM subjects (p<0.05 respectively). However, no significant changes in serum CXCL16 levels were found between T2DM and healthy subjects. Furthermore, serum CXCL16 concentration negatively correlated with estimated glomerular filtrate rate, creatinine clearance rate and blood albumin, and positively with 24 h proteinuria, blood urea nitrogen (BUN), creatinine, and uric acid after adjusting for age, gender and BMI in subjects with DN. Multiple stepwise regression analyses indicated that serum CXCL16 levels were independently associated with serum 24 h proteinuria, and BUN (p<0.05 respectively).

Conclusion

Serum CXCL16 may be an indicator of renal injury in subjects with T2DM. Understanding the exact mechanism of elevated CXCL16 in subjects with DN requires further study.     

Inhibition of Renal Glucose Reabsorption: A Novel Strategy for Achieving Glucose Control in Type 2 Diabetes Mellitus

ObjectiveTo review the renal handling of glucose and the role of inhibition of a sodium-glucose transporter (SGLT2) in the treatment of type 2 diabetes mellitus (T2DM).MethodsWe review the published data about (1) the filtration and reabsorption of glucose by the kidneys in normal subjects and patients with diabetes; (2) the deleterious effects of long-term elevation of plasma glucose levels on muscle and hepatic insulin sensitivity and beta cell function (that is, glucotoxicity); (3) the effect of inhibiting the SGLT2 transporter on the induction of glycosuria, glycemic control, insulin resistance, and beta cell dysfunction in animals and humans with diabetes; and (4) the safety of SGLT2 inhibition as a therapeutic modality to treat human T2DM.ResultsStudies in animal models of diabetes document the efficacy of the SGLT2 inhibitors in inducing glycosuria, decreasing both fasting and postprandial glucose levels, augmenting beta cell function, and enhancing hepatic and muscle insulin sensitivity. In human T2DM, short-term studies with dapagliflozin (12 weeks) and sergliflozin (2 weeks) have confirmed the efficacy of these agents in improving glycemic control. Excessive urinary electrolyte or water loss, plasma electrolyte disturbances, and hypoglycemia were not observed.ConclusionSGLT2 inhibitors represent a promising approach to the treatment of T2DM. They have the potential to be used as monotherapy, as well as in combination with all approved antidiabetic agents. Because their mechanism of action is independent of the severity of beta cell dysfunction or insulin resistance, efficacy should not decline with progressive beta cell failure or in the presence of severe insulin resistance. (Endocr Pract. 2008;14:782-790)     

A Panel of Serum Biomarkers Differentiates IgA Nephropathy from Other Renal Diseases

Background and Objectives

There is increasing evidence that galactose-deficient IgA1 (Gd-IgA1) and Gd-IgA1-containing immune complexes are important for the pathogenesis of IgA nephropathy (IgAN). In the present study, we assessed a novel noninvasive multi-biomarker approach in the diagnostic test for IgAN.

Materials and Methods

We compared serum levels of IgA, IgG, Gd-IgA1, Gd-IgA1-specific IgG and Gd-IgA1-specific IgA in 135 IgAN patients, 79 patients with non-IgAN chronic kidney disease (CKD) controls and 106 healthy controls. Serum was collected at the time of kidney biopsy from all IgAN and CKD patients.

Results

Each serum marker was significantly elevated in IgAN patients compared to CKD (P<0.001) and healthy controls (P<0.001). While 41% of IgAN patients had elevated serum Gd-IgA1 levels, 91% of these patients exhibited Gd-IgA1-specific IgG levels above the 90th percentile for healthy controls (sensitivity 89%, specificity 92%). Although up to 25% of CKD controls, particularly those with immune-mediated glomerular diseases including lupus nephritis, also had elevated serum levels of Gd-IgA1-specific IgG, most IgAN patients had elevated levels of Gd-IgA1-specific antibody of both isotypes. Serum levels of Gd-IgA1-specific IgG were associated with renal histological grading. Furthermore, there was a trend toward higher serum levels of Gd-IgA1-specific IgG in IgAN patients with at least moderate proteinuria (≥1.0 g/g), compared to patients with less proteinuria.

Conclusions

Serum levels of Gd-IgA1-specific antibodies are elevated in most IgAN patients, and their assessment, together with serum levels of Gd-IgA1, improves the specificity of the assays. Our observations suggest that a panel of serum biomarkers may be helpful in differentiating IgAN from other glomerular diseases.     

Serum Vascular Adhesion Protein-1 Predicts End-Stage Renal Disease in Patients with Type 2 Diabetes

Background

Diabetes is the leading cause of end-stage renal disease (ESRD) worldwide. Vascular adhesion protein-1 (VAP-1) participates in inflammation and catalyzes the deamination of primary amines into aldehydes, hydrogen peroxide, and ammonia, both of which are involved in the pathogenesis of diabetic complications. We have shown that serum VAP-1 is higher in patients with diabetes and in patients with chronic kidney disease (CKD), and can predict cardiovascular mortality in subjects with diabetes. In this study, we investigated if serum VAP-1 can predict ESRD in diabetic subjects.

Methods

In this prospective cohort study, a total of 604 type 2 diabetic subjects were enrolled between 1996 to 2003 at National Taiwan University Hospital, Taiwan, and were followed for a median of 12.36 years. The development of ESRD was ascertained by linking our database with the nationally comprehensive Taiwan Society Nephrology registry. Serum VAP-1 concentrations at enrollment were measured by time-resolved immunofluorometric assay.

Results

Subjects with serum VAP-1 in the highest tertile had the highest incidence of ESRD (p<0.001). Every 1-SD increase in serum VAP-1 was associated with a hazard ratio of 1.55 (95%CI 1.12–2.14, p<0.01) for the risk of ESRD, adjusted for smoking, history of cardiovascular disease, body mass index, hypertension, HbA1c, duration of diabetes, total cholesterol, use of statins, ankle-brachial index, estimated GFR, and proteinuria. We developed a risk score comprising serum VAP-1, HbA1c, estimated GFR, and proteinuria, which could predict ESRD with good performance (area under the ROC curve = 0.9406, 95%CI 0.8871–0.9941, sensitivity = 77.3%, and specificity = 92.8%). We also developed an algorithm based on the stage of CKD and a risk score including serum VAP-1, which can stratify these subjects into 3 categories with an ESRD risk of 0.101%/year, 0.131%/year, and 2.427%/year, respectively.

Conclusions

In conclusion, serum VAP-1 can predict ESRD and is a useful biomarker to improve risk stratification in type 2 diabetic subjects.     

2 型糖尿病患者凝血功能水平与血管病变发生的相关性

目的:探讨2型糖尿病患者凝血功能及血清肿瘤坏死因子α(TNF-α)及白细胞介素18(IL-18)水平与糖尿病血管病变的关系。方法:选择2014年6月-2015年10月在我院接受治疗的2型糖尿病患者83例作为研究对象,根据患者疾病进展情况将其分为血管病变组(45例)和无血管病变组(38例)。测定两组患者凝血酶时间(TT)、活化部分凝血酶原时间(APTT)、凝血酶原时间(PT)、纤维蛋白原(Fg)、血糖(Glu)、糖化血红蛋白(Hb A1c)、肿瘤坏死因子α(TNF-α)及白细胞介素18(IL-18)水平;采用logistics回归分析2型糖尿病患者发生血管病变的危险因素。结果:血管病变组患者Glu,Hb A1c及Fg水平均显著高于无血管病变组,而APTT及PT水平均显著低于无血管病变组,差异均具有统计学意义(P0.05);两组间TT水平比较,差异无统计学意义(P0.05)。血管病变组患者血清中TNF-α及IL-18水平均高于无血管病变组患者,差异具有统计学意义(P0.05)。Hb A1c,Fg,TNF-α以及IL-18水平异常是2型糖尿病患者发生血管病变的独立危险因素(OR=1.23,1.45,2.632,3.884,P0.05)。结论:凝血功能紊乱及炎症反应是2型糖尿病患者发生血管病变的重要因素,临床应给予重视。     

Preservation of Beta-Cell Function in Type 2 Diabetes

ObjectiveTo review available data on preservation and potential improvement of beta-cell function in patients with type 2 diabetes mellitus (T2DM) with use of currently available strategies and agents.MethodsUsing key words, we performed a MEDLINE search of the relevant literature published through 2009 regarding the effects of available agents on beta-cell function in humans with T2DM.ResultsOn the basis of current clinical data, no uniformly effective treatment for beta-cell preservation has been found. Lifestyle intervention and early intensive insulin therapy appear to have some preservative properties on beta-cell function. Glucagonlike peptide-1 agonists, dipeptidyl-peptidase-4 inhibitors, and thiazolidinediones result in maintenance and often improvement of beta-cell function during their active use; however, data on their ability to preserve beta-cell function when patients are not receiving active treatment are limited.ConclusionThe continuous loss of beta-cell mass and beta-cell function is a critical mechanism underlying the progressive deterioration of glycemic control in T2DM. In light of the projected increase in individuals at risk for developing T2DM, strategies and agents aimed at delaying or preventing the progression and inducing a remission of the disease are needed. Future research on this topic should include comparative efficacy trials with washout periods incorporating currently available and novel medications and strategies for preservation of beta cells. (Endocr Pract. 2010;16:1038-1055)     

2型糖尿病患者肾小管功能测定及其相关因素分析

目的：探讨2型糖尿病（DM）患者的肾小管功能改变,分析其相关因素。方法：将64例2型DM患者根据尿微量白蛋白量分为3组：正常蛋白尿组（〈30mg/24h）21例、微量白蛋白尿组（30~300mg/24h）20例和临床蛋白尿组（〉300mg/24h）23例,测定各组尿β2微球蛋白（U-β2MG）和尿渗透压（U-OSM）。探讨年龄、DM病程、24h尿白蛋白量、糖化血红蛋白、血压、血脂水平与肾小管功能损害的关系。结果：2型DM患者均有不同程度的尿β2MG增高及尿渗透压减低,在正常蛋白尿组即有4例尿β2-MG和7例尿OSM存在异常;方差分析显示,随尿白蛋白量的增高,尿β2MG逐步增高,尿渗透压逐步减低,三组间差异有统计学意义（F=26.123和13.889,P均〈0.01）,任两组比较差异均有统计学意义（P均〈0.05）。线性回归显示,尿β2MG及尿OSM改变与DM病程、尿白蛋白（U-ALB）、收缩压（SBP）、糖化血红蛋白（HbA1c）、总胆固醇（TC）、低密度脂蛋白（LDL-C）独立有关。结论：2型DM肾脏损害并非仅累及肾小球,在尿微量白蛋白出现之前即可出现肾小管功能异常。联合检测24h尿白蛋白量、尿β2-MG、尿OSM有助于全面评估2型糖尿病患者的肾脏损害情况。严格控制血糖,尽早纠正代谢紊乱对肾小管功能有保护作用。     

2 型糖尿病患者肾小管功能测定及其相关因素分析

目的:探讨2型糖尿病(DM)患者的肾小管功能改变,分析其相关因素。方法:将64例2型DM患者根据尿微量白蛋白量分为3组:正常蛋白尿组(<30mg/24h)21例、微量白蛋白尿组(30~300mg/24h)20例和临床蛋白尿组(>300mg/24h)23例,测定各组尿β2微球蛋白(U-β2MG)和尿渗透压(U-OSM)。探讨年龄、DM病程、24h尿白蛋白量、糖化血红蛋白、血压、血脂水平与肾小管功能损害的关系。结果:2型DM患者均有不同程度的尿β2MG增高及尿渗透压减低,在正常蛋白尿组即有4例尿β2-MG和7例尿OSM存在异常;方差分析显示,随尿白蛋白量的增高,尿β2MG逐步增高,尿渗透压逐步减低,三组间差异有统计学意义(F=26.123和13.889,P均<0.01),任两组比较差异均有统计学意义(P均<0.05)。线性回归显示,尿β2MG及尿OSM改变与DM病程、尿白蛋白(U-ALB)、收缩压(SBP)、糖化血红蛋白(HbA1c)、总胆固醇(TC)、低密度脂蛋白(LDL-C)独立有关。结论:2型DM肾脏损害并非仅累及肾小球,在尿微量白蛋白出现之前即可出现肾小管功能异常。联合检测24h尿白蛋白量、尿β2-MG、尿OSM有助于全面评估2型糖尿病患者的肾脏损害情况。严格控制血糖,尽早纠正代谢紊乱对肾小管功能有保护作用。     

Transcriptome Analysis of Proximal Tubular Cells (HK-2) Exposed to Urines of Type 1 Diabetes Patients at Risk of Early Progressive Renal Function Decline

Background

In patients with Type 1 Diabetes (T1D) who develop microalbuminuria, progressive decline in glomerular filtration rate (GFR) may be initiated by leakage into the urine of toxic proteins (txUPs). This study tested this hypothesis.

Methods

After archiving baseline urine, we followed T1D patients with microalbuminuria for 8–12 years to distinguish those in whom GFR declined (Decliners) and those in whom it remained stable (Non-decliners). Human proximal tubular cells (HK-2 cells) were grown in serum-free medium enriched with pooled urines from Decliners or Non-decliners. We determined genome-wide expression profiles in extracted mRNA.

Results

The two pooled urines induced differential expression of 312 genes. In terms of gene ontology, molecular functions of the 119 up-regulated genes were enriched for protein binding and peptidase inhibitor activities. Their biologic processes were enriched for defense response, responses to other organisms, regulation of cellular processes, or response to stress or stimulus, and programmed cell death. The 195 down-regulated genes were disproportionately represented in molecular functions of cation binding, hydrolase activity, and DNA binding. They were disproportionately represented in biological processes for regulation of metabolic processes, nucleic acid metabolic processes, cellular response to stress and macromolecule biosynthesis. The set of up-regulated genes in HK-2 cells overlaps significantly with sets of over-expressed genes in tubular and interstitial compartments of kidney biopsies from patients with advanced DN (33 genes in one study and 25 in the other compared with 10.3 expected by chance, p<10⁻⁹ and p<10⁻⁴, respectively). The overlap included genes encoding chemokines and cytokines. Overlap of down-regulated genes was no more than expected by chance.

Conclusions

Molecular processes in tubules and interstitium seen in advanced diabetic nephropathy can be induced in vitro by exposure to urine from patients with minimal microalbuminuria who subsequently developed progressive renal function decline, presumably due to putative txUPs.     

Deterioration in Motor Function Over Time in Older Adults With Type 2 Diabetes is Associated with Accelerated Cognitive Decline

Objective: Type 2 diabetes (T2D) is associated with motor impairments and a higher dementia risk. The relationships of motor decline with cognitive decline in T2D older adults has rarely been studied. Using data from the Israel Diabetes and Cognitive Decline study (N = 892), we examined associations of decline in motor function with cognitive decline over a 54-month period.Methods: Motor function measures were strength (handgrip) and gait speed (time to walk 3 m). Participants completed a neuropsychologic battery of 13 tests transformed into z-scores, summarized into 4 cognitive domains: episodic memory, attention/working memory, executive functions, and language/semantic categorization. The average of the 4 domains’ z-scores defined global cognition. Motor and cognitive functions were assessed in 18-months intervals. A random coefficients model delineated longitudinal relationships of cognitive decline with baseline and change from baseline in motor function, adjusting for sociodemographic, cardiovascular, and T2D-related covariates.Results: Slower baseline gait speed levels were significantly associated with more rapid decline in global cognition (P = .004), language/semantic categorization (P = .006) and episodic memory (P = .029). Greater decline over time in gait speed was associated with an accelerated rate of decline in global cognition (P = .050), attention/working memory (P = .047) and language/semantic categorization (P<.001). Baseline strength levels were not associated with cognitive decline but the rate of declining strength was associated with an accelerated decline in executive functions (P = .025) and language/semantic categorization (P = .006).Conclusion: In T2D older adults, the rate of decline in motor function, beyond baseline levels, was associated with accelerated cognitive decline, suggesting that cognitive and motor decline share common neuropathologic mechanisms in T2D.     

Liver Function Tests and Risk Prediction of Incident Type 2 Diabetes: Evaluation in Two Independent Cohorts

Background

Liver function tests might predict the risk of type 2 diabetes. An independent study evaluating utility of these markers compared with an existing prediction model is yet lacking.

Methods and Findings

We performed a case-cohort study, including random subcohort (6.5%) from 38,379 participants with 924 incident diabetes cases (the Dutch contribution to the European Prospective Investigation Into Cancer and Nutrition, EPIC-NL, the Netherlands), and another population-based cohort study including 7,952 participants with 503 incident cases (the Prevention of Renal and Vascular End-stage Disease, PREVEND, Groningen, the Netherlands). We examined predictive value of combination of the Liver function tests (gamma-glutamyltransferase, alanine aminotransferase, aspartate aminotransferase and albumin) above validated models for 7.5-year risk of diabetes (the Cooperative Health Research in the Region of Augsburg, the KORA study). Basic model includes age, sex, BMI, smoking, hypertension and parental diabetes. Clinical models additionally include glucose and uric acid (model1) and HbA1c (model2). In both studies, addition of Liver function tests to the basic model improved the prediction (C-statistic by∼0.020; NRI by∼9.0%; P<0.001). In the EPIC-NL case-cohort study, addition to clinical model1 resulted in statistically significant improvement in the overall population (C-statistic = +0.009; P<0.001; NRI = 8.8%; P<0.001), while addition to clinical model 2 yielded marginal improvement limited to men (C-statistic = +0.007; P = 0.06; NRI = 3.3%; P = 0.04). In the PREVEND cohort study, addition to clinical model 1 resulted in significant improvement in the overall population (C-statistic change = 0.008; P = 0.003; NRI = 3.6%; P = 0.03), with largest improvement in men (C-statistic change = 0.013; P = 0.01; NRI = 5.4%; P = 0.04). In PREVEND, improvement compared to clinical model 2 could not be tested because of lack of HbA1c data.

Conclusions

Liver function tests modestly improve prediction for medium-term risk of incident diabetes above basic and extended clinical prediction models, only if no HbA1c is incorporated. If data on HbA1c are available, Liver function tests have little incremental predictive value, although a small benefit may be present in men.     

替米沙坦联合叶酸对老年H型高血压合并2型糖尿病患者凝血功能及肾功的影响

目的:观察替米沙坦联合叶酸治疗对老年H型高血压合并2型糖尿病患者凝血功能及肾功的影响.为老年H型高血压合并2型糖尿病患者的临床治疗以及延缓病程提供理论依据.方法:选择66例符合标准的老年H型高血压合并2型糖尿病患者,测定血压,胰岛素敏感指数,糖化血红蛋白,同型半胱氨酸,凝血指标及尿白蛋白排泄率(UAE)等基线数据.上述患者随机分为对照组及实验组,分别接受替米沙坦80 mg/d及替米沙坦80 mg/d+叶酸片0.8 mg/d治疗后,于24周后复查上述指标,并与用药前进行对比研究.结果:对照组及实验组患者均较治疗前血压下降,糖化血红蛋白、纤维蛋白原、尿白蛋白排泄率明显下降(P＜0.05),胰岛素敏感指数较治疗前升高(P＜0.05).经治疗后,实验组患者较对照组血压、糖化血红蛋白、同型半胱氨酸、纤维蛋白原、尿白蛋白排泄率下降均低于对照组(P＜0.05),胰岛素敏感指数较对照组升高(P＜0.05).结论:对于老年H型高血压合并2型糖尿病患者替米沙坦联合叶酸治疗较单纯替米沙坦治疗具有更良好的降压作用,增加胰岛素敏感性,改善高凝状态,改善肾功.     

Longitudinal Study of the Decline in Renal Function in Healthy Subjects

Background

Chronic kidney disease is an important concern in preventive medicine, but the rate of decline in renal function in healthy population is not well defined. The purpose of this study was to determine reference values for the estimated glomerular filtration rate (eGFR) and rate of decline of eGFR in healthy subjects and to evaluate factors associated with this decline using a large cohort in Japan.

Methods

Retrospective cross-sectional and longitudinal studies were performed with healthy subjects aged ≥18 years old who received a medical checkup. Reference values for eGFR were obtained using a nonparametric method and those for decline of eGFR were calculated by mixed model analysis. Relationships of eGFR decline rate with baseline variables were examined using a linear least-squares method.

Results

In the cross-sectional study, reference values for eGFR were obtained by gender and age in 72,521 healthy subjects. The mean (±SD) eGFR was 83.7±14.7ml/min/1.73m². In the longitudinal study, reference values for eGFR decline rate were obtained by gender, age, and renal stage in 45,586 healthy subjects. In the same renal stage, there was little difference in the rate of decline regardless of age. The decline in eGFR depended on the renal stage and was strongly related to baseline eGFR, with a faster decline with a higher baseline eGFR and a slower decline with a lower baseline eGFR. The mean (±SD) eGFR decline rate was ‒1.07±0.42ml/min/1.73m²/year (‒1.29±0.41%/year) in subjects with a mean eGFR of 81.5±11.6ml/min/1.73m².

Conclusions

The present study clarified for the first time the reference values for the rate of eGFR decline stratified by gender, age, and renal stage in healthy subjects. The rate of eGFR decline depended mainly on baseline eGFR, but not on age, with a slower decline with a lower baseline eGFR.     

2型糖尿病大鼠模型的肾脏和动脉血管并发症

目的制备发病过程类似人类2型糖尿病的动物模型,并观察其肾脏和主动脉的病变特点。方法8周龄SD大鼠高脂、高糖饮食一个月后给予小剂量STZ腹腔注射建立2型糖尿病模型,于成模后4周及8周观察血管功能指标和肾脏功能指标,并对肾脏和血管的病理改变进行观察。结果模型组于成模后4周及8周出现高血糖、高血脂、胰岛素抵抗、肾功能改变和血管功能改变。肾脏光镜下见肾小球内皮及系膜细胞增生;肾小管水肿,管腔内有大量蛋白管型和细胞管型;肾盂区有大量淋巴细胞浸润。动脉血管电镜下见内皮细胞局部损伤严重;内皮细胞与内弹力板连接处空隙增加等。结论用高脂高糖饮食加小剂量STZ腹腔注射可成功制备2型糖尿病大鼠模型,成模后4周及8周后观察肾脏及大血管相继出现病变,是2型糖尿病血管病变研究的理想模型。     

Plasma Protein Biomarkers Correlated with the Development of Diet-Induced Type 2 Diabetes in Mice

Introduction

Early detection, assessment of disease progression, and application of an appropriate therapeutic intervention are all important for the care of patients with type 2 diabetes. Currently, however, there is no simple test for early detection of type 2 diabetes. Established diagnostic tests for the disease including oral glucose tolerance, fasting blood glucose, and hemoglobin A1c are relatively late markers where the disease has already progressed. Since blood is in direct contact with many tissues, we hypothesized that pathological tissue changes are likely to be reflected in proteomic profiles of plasma.

Methods

Mice were reared either on regular chow or a high-fat diet at weaning and several physiological responses (i.e., weight, fasting plasma glucose and insulin, and glucose tolerance) were monitored at regular time intervals. Plasma was collected at regular intervals for proteomic analysis by two-dimensional gel electrophoresis and subsequent mass spectrometry.

Results

Onset of hyperinsulinemia with corresponding glucose intolerance was observed in 2 weeks and fasting blood glucose levels rose significantly after 4 weeks on the high-fat diet. Many proteins were found to exist in multiple forms (isoforms). Levels of some isoforms including plasma retinol binding protein, transthyretin, Apolipoprotein A1, and kininogen showed significant changes as early as 4 weeks which coincided with the very early development of glucose intolerance.

Conclusions

These results show that a proteomic approach to study the development of type 2 diabetes may uncover unknown early post-translationally modified diagnostic and/or therapeutic protein targets.     

Multi-Scale Glycemic Variability: A Link to Gray Matter Atrophy and Cognitive Decline in Type 2 Diabetes

Objective

Type 2 diabetes mellitus (DM) accelerates brain aging and cognitive decline. Complex interactions between hyperglycemia, glycemic variability and brain aging remain unresolved. This study investigated the relationship between glycemic variability at multiple time scales, brain volumes and cognition in type 2 DM.

Research Design and Methods

Forty-three older adults with and 26 without type 2 DM completed 72-hour continuous glucose monitoring, cognitive tests and anatomical MRI. We described a new analysis of continuous glucose monitoring, termed Multi-Scale glycemic variability (Multi-Scale GV), to examine glycemic variability at multiple time scales. Specifically, Ensemble Empirical Mode Decomposition was used to identify five unique ultradian glycemic variability cycles (GVC_1–5) that modulate serum glucose with periods ranging from 0.5–12 hrs.

Results

Type 2 DM subjects demonstrated greater variability in GVC_3–5 (period 2.0–12 hrs) than controls (P<0.0001), during the day as well as during the night. Multi-Scale GV was related to conventional markers of glycemic variability (e.g. standard deviation and mean glycemic excursions), but demonstrated greater sensitivity and specificity to conventional markers, and was associated with worse long-term glycemic control (e.g. fasting glucose and HbA1c). Across all subjects, those with greater glycemic variability within higher frequency cycles (GVC_1–3; 0.5–2.0 hrs) had less gray matter within the limbic system and temporo-parietal lobes (e.g. cingulum, insular, hippocampus), and exhibited worse cognitive performance. Specifically within those with type 2 DM, greater glycemic variability in GVC_2–3 was associated with worse learning and memory scores. Greater variability in GVC₅ was associated with longer DM duration and more depression. These relationships were independent of HbA1c and hypoglycemic episodes.

Conclusions

Type 2 DM is associated with dysregulation of glycemic variability over multiple scales of time. These time-scale-dependent glycemic fluctuations might contribute to brain atrophy and cognitive outcomes within this vulnerable population.     

Assessment of Metabolomic and Proteomic Biomarkers in Detection and Prognosis of Progression of Renal Function in Chronic Kidney Disease

Chronic kidney disease (CKD) is part of a number of systemic and renal diseases and may reach epidemic proportions over the next decade. Efforts have been made to improve diagnosis and management of CKD. We hypothesised that combining metabolomic and proteomic approaches could generate a more systemic and complete view of the disease mechanisms. To test this approach, we examined samples from a cohort of 49 patients representing different stages of CKD. Urine samples were analysed for proteomic changes using capillary electrophoresis-mass spectrometry and urine and plasma samples for metabolomic changes using different mass spectrometry-based techniques. The training set included 20 CKD patients selected according to their estimated glomerular filtration rate (eGFR) at mild (59.9±16.5 mL/min/1.73 m²; n = 10) or advanced (8.9±4.5 mL/min/1.73 m²; n = 10) CKD and the remaining 29 patients left for the test set. We identified a panel of 76 statistically significant metabolites and peptides that correlated with CKD in the training set. We combined these biomarkers in different classifiers and then performed correlation analyses with eGFR at baseline and follow-up after 2.8±0.8 years in the test set. A solely plasma metabolite biomarker-based classifier significantly correlated with the loss of kidney function in the test set at baseline and follow-up (ρ = −0.8031; p<0.0001 and ρ = −0.6009; p = 0.0019, respectively). Similarly, a urinary metabolite biomarker-based classifier did reveal significant association to kidney function (ρ = −0.6557; p = 0.0001 and ρ = −0.6574; p = 0.0005). A classifier utilising 46 identified urinary peptide biomarkers performed statistically equivalent to the urinary and plasma metabolite classifier (ρ = −0.7752; p<0.0001 and ρ = −0.8400; p<0.0001). The combination of both urinary proteomic and urinary and plasma metabolic biomarkers did not improve the correlation with eGFR. In conclusion, we found excellent association of plasma and urinary metabolites and urinary peptides with kidney function, and disease progression, but no added value in combining the different biomarkers data.     

Ultra Rapid-Acting Inhaled Insulin Improves Glucose Control in Patients With Type 2 Diabetes Mellitus

ObjectiveTo determine whether the use of an inhaled insulin would improve HbA1c.MethodsThis study was performed in 20 type 2 diabetes mellitus (T2DM) participants with HbA1c values ≥7.5 (58) to ≤11.5% (102 mmol/mol) on a variety of glucose-lowering regimens. Prandial Technosphere insulin (TI) was rapidly titrated based on a treatment algorithm using postprandial blood glucose to calculate premeal doses. A 2-week baseline period was followed by 12 weeks of active treatment with TI. The primary outcome was change in HbA1c. Secondary outcomes included glucose time in range (time in range: 70-180 mg/dL) obtained by a blinded continuous glucose monitoring during the baseline period and at the end of 12 weeks. Goals were to assess how to rapidly and safely initiate TI intensification, determine dosing requirements, and establish an effective dose range in uncontrolled T2DM.ResultsMean HbA1c decreased by −1.6% (−17 mmol/mol) from 9.0% (75 mmol/mol) at baseline to 7.4% (57 mmol/mol) at 12 weeks (P < .0001). Mean time in range increased from 42.2% to 65.7% (P < .0002). Mean prandial doses of TI were 18 or 19 units for all meals. Time below range was 1.1% baseline and 2.6% post treatment (P = .01).ConclusionTreatment with inhaled TI dosed using a simple algorithm improved glycemic control measured by both HbA1c and time in range, with low rates of hypoglycemia. These data add significantly to understanding TI in the management of T2DM patients for whom prandial insulin is a consideration.