Receptor for advanced glycation endproducts signaling cascades are activated in pancreatic fibroblasts,but not in the INS1E insulinoma cell line: Are mesenchymal cells major players in chronic inflammation?

The receptor for advanced glycation endproducts (RAGE) is a pattern recognition receptor that plays an important role in natural immunity. It is suggested that mesenchymal cells are the major players during inflammation. Previously, we reported that advanced glycation end products (AGE), known to be one of the ligands of RAGE, inhibited glucose-induced insulin secretion from ex vivo pancreatic islets, although the mechanism responsible remains largely unknown. In the present study, we examined the cascades operating downstream from RAGE using the insulinoma cell line INS1E and primary-cultured pancreatic fibroblasts as in vitro models for parenchymal (β) cells and mesenchymal cells, respectively. Phosphorylation of c-jun N-terminal kinase, inhibitor of nuclear factor κB kinase, and nuclear factor κB was stimulated by AGE or high mobility group binding 1 (HMGB1) in pancreatic fibroblasts, whereas no such effect was observed in INS1E cells. Expression of the Ccl5, Il-6, and Il-1b genes was increased by AGE/HMGB1 in fibroblasts, but not in INS1E cells. On the other hand, AGE inhibited the secretion of insulin from ex vivo pancreatic islets, and this effect was ameliorated by MK615, a Japanese apricot extract used as an anti-inflammatory agent. Glucose-induced insulin secretion from INS1E cells was not affected by direct administration of AGE/HMGB1, but was inhibited by fibroblast-conditioned medium. These results suggest that AGE suppresses glucose-induced insulin secretion from pancreatic islets through indirect mesenchymal RAGE signaling.     

Controlling the receptor for advanced glycation end‐products to conquer diabetic vascular complications

Diabetic vascular complications, such as cardiovascular disease, stroke and microangiopathy, lead to high rates of morbidity and mortality in patients with long‐term diabetes. Extensive intracellular and extracellular formation of advanced glycation end‐products (AGE) is considered a causative factor in vascular injuries in diabetes. Receptor‐dependent mechanisms are involved in AGE‐induced cellular dysfunction and tissue damage. The receptor for AGE (RAGE), originally an AGE‐binding receptor, is now recognized as a member of pattern‐recognition receptors and a pro‐inflammatory molecular device that mediates danger signals to the body. Previous animal studies have shown RAGE dependent of diabetic vascular injuries. Prophylactic and therapeutic strategies focusing on RAGE and its ligand axis will be of great importance in conquering diabetic vascular complications. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00191.x, 2012)     

Association between serum levels of soluble receptor for advanced glycation end products and circulating advanced glycation end products in type 2 diabetes

Aims/hypothesis Activation of the receptor for advanced glycation end products (RAGE, also known as AGE-specific receptor [AGER]) has been implicated in the development of diabetic vascular complications. Blockade of RAGE using a soluble form of the receptor (sRAGE) suppressed vascular hyperpermeability and atherosclerosis in animal models. Since little is known about the regulation of endogenous sRAGE levels, we determined whether serum sRAGE is influenced by circulating AGEs and the severity of nephropathy in type 2 diabetic patients.Materials and methods We recruited 150 healthy control and 318 diabetic subjects. Diabetic subjects were subdivided into those with proteinuria, microalbuminuria or normoalbuminuria. Serum sRAGE was assayed by ELISA and serum AGEs by competitive ELISA using a polyclonal rabbit antiserum raised against AGE-RNase.Results Diabetic subjects had higher sRAGE (1,029.5 pg/ml [766.1–1,423.0] interquartile range vs 1,002.6 [726.5–1,345.3], p<0.05) and AGEs (4.07±1.13, SD, unit/ml vs 3.39±1.05, p<0.01) than controls. Proteinuric subjects had the highest sRAGE levels and there was a significant trend between the severity of nephropathy and sRAGE (p=0.01). In diabetic subjects, serum log(sRAGE) correlated with AGEs (r=0.27, p<0.001), log(plasma creatinine) (r=0.31, p<0.001), log(urine AER) (r=0.24, p<0.01) and log(triglycerides) (r=0.15, p<0.01). On stepwise linear regression analysis, AGEs and creatinine levels were the main independent determinants of sRAGE concentration.Conclusions/interpretation Serum sRAGE levels and circulating AGEs are associated with the severity of nephropathy in type 2 diabetic patients. Prospective studies are required to determine whether endogenous sRAGE potentially influences the development of diabetic vascular complications.     

Serum soluble receptor for advanced glycation end‐products during acute bronchiolitis in infant: Prospective study in 93 cases

Introduction

Acute bronchiolitis is a major cause of acute respiratory distress in infants. The soluble receptor for advanced glycation end‐products (sRAGE) is a biomarker of pulmonary damage processes, with a diagnostic and a prognostic value in acute respiratory distress syndrome (ARDS). The RAGE pathway is also implicated in the pathogenesis of other respiratory diseases like asthma, but the value of sRAGE levels in acute bronchiolitis remains under‐investigated.

Material and methods

A prospective, observational, and analytical study was conducted at Clermont‐Ferrand University Hospital. The main objective was to evaluate the correlation between serum sRAGE and clinical severity of bronchiolitis in hospitalized infants aged <1 year. We analyzed correlations between serum sRAGE and Wainwright score, short‐term morbidity attributable to bronchiolitis, causal viruses and risk for recurrent wheezing at 1 year.

Results

The study included 93 infants. sRAGE levels were significantly lower in acute bronchiolitis patients (mean 1101 pg/mL) than in controls (2203 pg/mL, P < 0.001) but did not correlate with clinical severity. No correlation was found between serum sRAGE and severity score, respiratory viruses, and recurrent wheezing at 1 year. Serum sRAGE levels were negatively correlated with age (r = −0.45, P < 0.001).

Conclusion

Serum sRAGE levels are decreased in acute bronchiolitis but not correlated with disease severity. sRAGE levels should be age‐adjusted in infants. Serum sRAGE levels measured in the setting of acute bronchiolitis were not predictive of recurrent wheezing.

     

Effects of Icodextrin and Glucose Bicarbonate/Lactate‐Buffered Peritoneal Dialysis Fluids on Effluent Cell Population and Biocompatibility Markers IL‐6 and CA125 in Incident Peritoneal Dialysis Patients

Icodextrin peritoneal dialysis (PD) solution has been shown to increase interleukin‐6 (IL‐6) levels in PD effluent as well as leukocyte and mesothelial cell count. Mesothelial cells release cancer antigen 125 (CA125), which is used as a marker of mesothelial cell mass. This 1‐year prospective study was designed to compare peritoneal effluent cell population, its inflammatory phenotype and biocompatibility biomarkers IL‐6 and CA125 between icodextrin (E) and glucose bicarbonate/lactate (P) based PD solutions. Using baseline peritoneal ultrafiltration capacity, 19 stable incident PD patients were allocated either to P only (N = 8) or to P plus E for the overnight dwell (N = 11). Flow cytometry was used to measure white blood cell count and differential and the expression of inflammatory molecules on peritoneal cells isolated from timed overnight peritoneal effluents. Compared to P, E effluent showed higher leukocyte (10.9 vs. 7.9), macrophages (6.1 vs. 2.5) and mesothelial cells (0.3 vs. 0.1)×10⁶/L count, as well as expression of HLA DR on mesothelial cells and IL‐6 (320.5 vs. 141.2 pg/min) on mesothelial cells and CA125 appearance rate (159.6 vs. 84.3 IU/min), all P < 0.05. In the E group, correlation between IL‐6 and CA125 effluent levels (r = 0.503, P < 0.05) as well as appearance rates (r = 0.774, P < 0.001) was demonstrated. No effect on systemic inflammatory markers or peritoneal permeability was found. Icodextrin PD solution activates local inflammation without systemic consequences so the clinical relevance of this observation remains obscure. Correlation between effluent IL‐6 and CA125 suggests that CA125 might be upregulated due to inflammation and thus is not a reliable marker of mesothelial cell mass and/or biocompatibility.     

Glycation and cardiovascular disease in diabetes: A perspective on the concept of metabolic memory

Epidemiological studies have suggested that cumulative diabetic exposure, namely prolonged exposure to chronic hyperglycemia, contributes to the increased risk of cardiovascular disease (CVD) in diabetes. The formation and accumulation of advanced glycation end‐products (AGEs) have been known to progress under hyperglycemic conditions. Because AGEs‐modified collagens are hardly degraded and remain in diabetic vessels, kidneys and the heart for a long time, even after glycemic control has been achieved, AGEs could become a marker reflecting cumulative diabetic exposure. Furthermore, there is a growing body of evidence that an interaction between AGEs and the receptor for AGEs (RAGE) plays a role in the pathogenesis of CVD. In addition, AGEs induce the expression of RAGE, thus leading to sustained activation of the AGEs–RAGE axis in diabetes. Herein we review the pathological role of the AGEs–RAGE axis in CVD, focusing particularly on the phenomenon of metabolic memory, and discuss the potential clinical usefulness of measuring circulating and tissue levels of AGEs accumulation to evaluate diabetic macrovascular complications.     

Plasma gastric inhibitory polypeptide and glucagon‐like peptide‐1 levels after glucose loading are associated with different factors in Japanese subjects

Aims/Introduction: Gastric inhibitory polypeptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) are major incretins that potentiate insulin secretion from pancreatic β‐cells. The factors responsible for incretin secretion have been reported in Caucasian subjects, but have not been thoroughly evaluated in Japanese subjects. We evaluated the factors associated with incretin secretion during oral glucose tolerance test (OGTT) in Japanese subjects with normal glucose tolerance (NGT). Materials and Methods: We measured plasma GIP and GLP‐1 levels during OGTT in 17 Japanese NGT subjects and evaluated the factors associated with GIP and GLP‐1 secretion using simple and multiple regression analyses. Results: GIP secretion (AUC‐GIP) was positively associated with body mass index (P < 0.05), and area under the curve (AUC) of C‐peptide (P < 0.05) and glucagon (P < 0.01), whereas GLP‐1 secretion (AUC‐GLP‐1) was negatively associated with AUC of plasma glucose (P < 0.05). The insulinogenic index was most strongly associated with GIP secretion (P < 0.05); homeostasis model assessment β‐cell was the most the strongly associated factor in GLP‐1 secretion (P < 0.05) among the four indices of insulin secretion and insulin sensitivity. Conclusions: Several distinct factors might be associated with GIP and GLP‐1 secretion during OGTT in Japanese subjects. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00078.x, 2011)     

Advanced glycation end‐products are a risk for muscle weakness in Japanese patients with type 1 diabetes

Accumulation of advanced glycation end‐products (AGEs) is thought to contribute to muscle weakness in a diabetic animal model. Skin autofluorescence is a proposed marker for accumulation of AGEs in the skin. We aimed to investigate the relationship between AGEs accumulation, sarcopenia and muscle function of Japanese patients with type 1 diabetes. A total of 36 patients with type 1 diabetes participated in the present cross‐sectional study. Sarcopenia parameters (skeletal muscle mass index and knee extension strength) were compared with subcutaneous AGEs accumulation using skin autofluorescence. The prevalence of sarcopenia and impaired knee extension strength was 16.6% (men 0.0%, women 22.2%) and 47.2% (men 22.2%, women 55.6%), respectively. Knee extension strength was negatively correlated with skin autofluorescence (r² = 0.14, P < 0.05), but not with skeletal muscle mass index. In conclusion, the AGEs accumulation might be one of the reasons of impaired lower limb muscle function in Japanese patients with type 1 diabetes.     

Soluble receptor for advanced glycation end products (sRAGE) is present at high concentrations in the lungs of children and varies with age and the pattern of lung inflammation

Background and objective: The soluble receptor for advanced glycation end products (sRAGE) plays an important role in inflammation. Few studies have looked at sRAGE levels in human lungs, and there is no information in children. Therefore, this study aimed to compare bronchoalveolar lavage fluid (BALF) and plasma sRAGE concentrations in children in relation to age and inflammation. Methods: BAL was performed in 76 children, and BALF and plasma sRAGE levels were determined by enzyme‐linked immunosorbent assay. Results: sRAGE levels were fourfold higher in BALF than in plasma (P < 0.001). BALF sRAGE was inversely proportional to age (r = ?0.333, P = 0.008) and serum immunoglobulin A (r = ?0.283, P = 0.028). Plasma sRAGE showed a positive correlation to the percentage of BAL macrophages and negative correlation to the percentage of neutrophils and lymphocytes (P < 0.05). Multivariate linear regression analysis identified that the percentage of BAL lymphocytes and neutrophils were significant independent predictors of plasma sRAGE levels, while age and the percentage of BAL macrophages independently predicted BALF sRAGE levels. Conclusions: In children, sRAGE is present at higher concentrations in the lung compared with blood. It appears that sRAGE varies with age, and hence future studies of sRAGE in paediatric lung disease require age matching. The significant relationship between sRAGE and lung inflammation warrants further research.     

Associations of Peritoneal Glucose Load With Male Sexual Dysfunction and Depression in Peritoneal Dialysis Patients

This cross‐sectional study examined possible associations of peritoneal glucose load with male sexual dysfunction and depression in peritoneal dialysis patients. Compared to patients with peritoneal glucose load ≤3 g/kg per day, those with load >3 g/kg per day had higher Beck Depression Inventory scores, (18.9 ± 5.4 vs. 11.4 ± 5.8, P = 0.002) and lower International Index of Erectile Function scores, serum total testosterone and DHEA [(15.4 ± 6.4 vs. 45.1 ± 20.7, P < 0.001), (8.5 ± 3.0 vs. 13.9 ± 3.2, P < 0.001), (113.9 ± 58.8 vs. 280.2 ± 128.3, P < 0.001); respectively)]. Of participants with peritoneal glucose load >3 g/kg per day, 84.6% had mild to moderate erectile dysfunction and 92.3% had abnormal Beck Depression Inventory scores. Peritoneal glucose load inversely correlated with International Index of Erectile Function scores (P < 0.001), total serum testosterone (P = 0.002) and serum DHEA (P = 0.001); and directly with Beck Depression Inventory scores (P < 0.001) and serum estradiol (P < 0.001). This study demonstrated higher prevalence of sexual dysfunction, depression and sex hormone disturbances in male peritoneal dialysis patients receiving higher peritoneal glucose load.     

The pattern recognition reagents RAGE VC1 and peptide p5 share common binding sites and exhibit specific reactivity with AA amyloid in mice

Abstract

In the US, there remains a need to develop a clinical method for imaging amyloid load in patients with systemic, visceral amyloidosis. The receptor for advanced glycation end products (RAGE), which exists as a transmembrane receptor and soluble variant, is found associated with a number of amyloid deposits in man. It is unclear whether amyloid-associated RAGE is the membrane or soluble form; however, given the affinity of RAGE for amyloid, we have examined the ability of soluble RAGE VC1 to specifically localize with systemic AA amyloid in mice. We further compared the reactivity of RAGE VC1 with that of the synthetic, amyloid-reactive peptide p5.

Methods: Binding of radiolabeled RAGE VC1 and p5 to synthetic amyloid fibrils was evaluated using in vitro “pulldown” assays in the presence or absence of RAGE ligands. Radioiodinated RAGE VC1 and technetium-99?m-labeled p5 were studied in mice with systemic AA amyloidosis using dual-energy SPECT/CT imaging, biodistribution and microautoradiography.

Results: Soluble RAGE VC1 competed with radioiodinated peptide p5 for binding to rVλ6Wil, Aβ (1–40) and IAPP fibrils but not with the higher affinity peptide, p5R. Pre-incubation with AGE-BSA abrogated binding of VC1 and p5 to rVλ6Wil fibrils. Dual-energy SPECT/CT images and quantitative tissue biodistribution data showed that soluble RAGE VC1 specifically bound AA amyloid-laden organs in mice as effectively as peptide p5. Furthermore, microautoradiography confirmed that RAGE VC1 bound specifically to areas of Congo red-positive amyloid in mouse tissues but not in comparable tissues from control WT mice.

Conclusion: Soluble RAGE VC1 and peptide p5 have similar ligand binding properties and specifically localize with visceral AA amyloid deposits in mice.     

Advanced glycation end products depress function of endothelial progenitor cells via p38 and ERK 1/2 mitogen-activated protein kinase pathways

Objective  Advanced glycation end products (AGEs) and endothelial progenitor cells (EPCs) play divergent roles in the process of atherosclerosis. We investigated the effects of AGE-human serum albumin (AGE-HSA) on receptor expression for AGEs (RAGE) and EPCs apoptosis. Methods  The human mononuclear cells were obtained by Ficoll density gradient centrifugation and cultured in M199 medium containing rh-VEGF (30 ng/ml), rh-b-FGF(6 ng/ml) and 20% NBCS for 8 days. The adhesive EPCs were sequentially harvested after 24 h synchronization and challenged with AGE-HSA (concentration range from 0 to 300 μg/ml) for 24 h and 200 μg/ml AGE-HSA (time range from 0 to 36 h). EPCs apoptosis and migration were determined, expressions of RAGE, phosphorylated ERK1/2, JNK and p38 mitogen-activated protein kinase (MAPK) of EPCs were quantified by fluorescent quantitation RT-PCR and Western-blot, effect of AGE-HSA on NF-κB activtiy was determined by EMSA (electrophoretic mobility shift assay) in the presence and absence of special MAPK pathways pathway inhibitors. Results  AGE-HSA upregulated the expression of RAGE, this effect could be significantly inhibited by p38 MAPK and ERK MAPK inhibitor, but not by JNK MAPK inhibitor. AGE-HSA also promoted EPCs apoptosis and inhibited EPCs migration and increased NF-κB activity, these effects could be significantly attenuated by the anti-RAGE neutralizing antibody as well as by p38 and ERK MAPK inhibitors. Conclusion  AGE-HSA could promote atherosclerosis by upregulating EPCs RAGE expressions and promoting EPCs apoptosis via p38, ERK MAPK pathways, activation of NF-κB might also play a role in this process. C. Sun and C. Liang contributed equally to this work. Returned for 1. Revision: 13 December 2007 1. Revision received: 20 February 2008 Returned for 2. Revision: 7 March 2008 2. Revision received: 9 June 2008     

Role of the advanced glycation end products receptor in Crohn’s disease inflammation

AIM:To investigate the level of mucosal expression and the involvement of the receptor for the advanced glycation end products(RAGE)in delayed apoptosis and tumor necrosis factor(TNF)-αproduction in Crohn’s disease(CD).METHODS:Surgical and endoscopic specimens from both inflamed and non-inflamed areas of the ileum and/or colon were collected from 20 and 14 adult CD patients,respectively,and used for the assessment of RAGE expression by means of immunohistochemistry and western blotting analysis.Normal tissues from 21 control subjects were used for comparison.The same polyclonal anti-human RAGE antibody(R and D System)was used in all experimental conditions.RAGE staining was quantized by a score including both the amount of positive cells and intensity of immunoreactivity;cellular pattern was also described.The effects of RAGE blocking on apoptotic rate and TNF-αproduction were investigated on immune cells freshly isolated from CD mucosa and incubated both with and without the muramyl dipeptide used as antigenic stimulus.Statistical analysis was performed via the test for trend,with regression models to account for intra-patient correlations.A 2-sided P<0.05 was considered significant.RESULTS:In inflamed areas,RAGE expression in both the epithelial and lamina propria compartments was higher than control tissues(P=0.001 and 0.021,respectively),and a cluster of positive cells were usually found in proximity of ulcerative lesions.Similar results were obtained in the lamina propria compartment of non-inflamed areas(P=0.025).The pattern of staining was membranous and granular cytosolic at the epithelial level,while in the lamina propria it was diffuse cytosolic.When evaluating the amount of protein expression by immunoblotting,a significant increase of both surface area and band intensity(P<0.0001 for both)was observed in CD inflamed areas compared to control tissue,while in non-inflamed areas a significant increase was found only for band intensity(P<0.005).Moreover,a significantly lower expression in no     

RAGE‐ligands axis: A new ‘driving force’ for cigarette smoke‐induced airway inflammation in COPD?

Receptor for advanced glycation end products (RAGE) was recently shown to contribute to cigarette smoke (CS)‐induced airway inflammation in chronic obstructive pulmonary disease (COPD). In this study, RAGE small interfering ribonucleic acid (RNA) transfection attenuated increased messenger RNA levels of common RAGE ligands HMGB1, S100A8, S100A9 and S100A12, but not S100B following exposure to CS extract. Our findings and those from recent studies suggest a positive feedback involving RAGE and its ligands as a new ‘driving force’ for CS‐induced airway inflammation in COPD.     

晚期糖基化终末产物受体在心血管疾病中的研究进展

晚期糖基化终末产物受体(RAGE)属于细胞表面免疫球蛋白超家族中的一员,广泛表达于人体内皮细胞、平滑肌细胞、系膜细胞、心肌细胞、单核巨噬细胞和神经元细胞等。RAGE不仅参与炎症反应,还与糖尿病慢性并发症的发生、发展,类风湿性关节炎,肿瘤的侵袭和转移,阿尔茨海默病,慢性肾病等有关。现主要论述其在心血管疾病中的作用。     

Association of circulating proinflammatory marker,leucine‐rich‐α2‐glycoprotein (LRG1), following metabolic/bariatric surgery

Background

Obesity confers substantial excess risk for morbidity and mortality, especially for type 2 diabetes (T2D). Leucine‐rich‐α2‐glycoprotein 1 (LRG1), a novel proinflammatory factor, was recently reported to be higher in patients with T2D with complications of peripheral arterial disease. Association of LRG1, obesity, and weight loss is unknown. We examined whether plasma LRG1 is associated with obesity in health screening participants and if it predicts future weight loss in morbidly obese patients after metabolic/bariatric surgery.

Methods

Cohort 1 was a cross‐sectional study from a Health Screening program (n = 616) in a tertiary hospital. Cohort 2 was a prospective study of morbidly obese patients (n = 231) who underwent metabolic/bariatric surgery with follow‐up weight measurements. Anthropometric data, baseline fasting glucose, plasma adiponectin, high sensitivity C‐reactive protein (HsCRP), and LRG1 were measured. Postsurgery blood, after metabolic/bariatric surgery, were available for LRG1and HsCRP measurements in 57 patients.

Results

In the group with highest tertile of LRG1, body mass index (BMI), waist circumference, and HsCRP were significantly higher, while total cholesterol, high‐density lipoprotein, low‐density lipoprotein, and adiponectin were lower than tertiles 1 and 2. Generalized linear model analysis showed that female gender (P < .0001), non‐Chinese ethnicity (P < .019), and higher HsCRP (P < .0001) levels were independent and significant determinants of higher plasma LRG1 levels. After adjustment for age, gender, ethnicity, and baseline BMI, female gender (P = .020), higher presurgery BMI (P = .001), and lower presurgery LRG1 (P = .002) remained statistically significant predictors for greater weight loss. Plasma LRG1 increased significantly [from 28.2 (21.9‐36.8) to 34.9 (22.6‐49.5)] μg/mL (P = .003) within 1.5 months, after metabolic/bariatric surgery.

Conclusions

Our study demonstrates that LRG1 level is positively associated with obesity and a lower level of plasma LRG1 predicts weight loss in metabolic/bariatric surgery. Our novel findings suggest LRG1, itself or in combination with other known factors, is a potential biomarker of inflammation and obesity.     

The different roles for the advanced glycation end products axis in heart failure and acute coronary syndrome settings

AimsThis work aimed to compare the behavior of the advanced glycation end products (AGEs) and their soluble receptor (sRAGE) in two cohorts of patients: those with heart failure (HF) and acute coronary syndrome (ACS).Methods and resultsA unicentric observational clinical study was performed in 102 patients with ACS and 102 patients with chronic HF matched by age and gender. At inclusion, fluorescent AGEs were measured by quantitative fluorescence spectroscopy of plasma, and total sRAGE and endogenous secretory RAGE (esRAGE) levels were determined by enzyme-linked immunosorbent assay kits. A 5-year follow-up period was established for recording cardiac death (primary endpoint) and the incidence of non-fatal myocardial infarction or HF readmission (secondary endpoints). Higher glycation parameters were observed in HF patients, whereas no differences in sRAGE forms were found between HF and ACS cohorts, except for cRAGE, which was higher in HF. Associations between glycation parameters and sRAGE forms were observed in HF, but not in ACS. Differences were also evidenced in the long-term prognosis of each cohort: esRAGE showed an independent prognostic value for cardiac death or non-fatal cardiovascular events in HF, but none of the AGE–RAGE variables were predictors in ACS.ConclusionsA different role for the AGE–RAGE axis was observed in HF and ACS. All the sRAGE forms were directly related with glycation parameters in HF, but not in ACS. The independent value of the sRAGE forms on each cardiovascular disease was supported by esRAGE being an independent predictor of bad long-term prognosis only for HF.     

Inhibition of glucose production and stimulation of bile flow by R (+)‐α‐lipoic acid enantiomer in rat liver

Abstract: Aims/Background: R (+)‐α‐lipoic acid (RLA) has been suggested for the treatment of liver diseases, but has also been shown to improve glucose utilization in diabetic patients. Because detailed information of RLA action on carbohydrate metabolism in intact liver is lacking, we examined concentration‐dependent effects of RLA on hepatic glucose production. Methods: RLA (10^?6?10^?3 mol L^?1) or buffer (control) was infused in isolated livers of fasted rats during recirculating perfusion for 90 min (n = 4–6/group). Hepatic glucose and lactate fluxes and bile secretion were continuously monitored. Results: RLA reduced lactate (10 mmol L^?1)‐dependent glucose production in concentration‐dependent fashion (R = ? 0.780, P < 0.001) by up to 67% compared with control (0.36 ± 0.02 µmol min^?1 g^?1). In parallel, RLA dose dependently decreased lactate uptake (R = ? 0.592, P < 0.001) also by up to 67% (control: 0.58 ± 0.08 µmol min^?1 g^?1). RLA (10^?4 mol L^?1 and 10^?3 mol L^?1) stimulated bile flow by ～ 20 and ～ 50%, respectively (P < 0.02 vs. control). After 10^?3 mol L^?1 RLA infusion, liver glycogen was ～ 3 fold higher (5.2 ± 1.1 vs. control: 1.8 ± 0.2 µmol g^?1, P < 0.002). Also at low lactate concentrations (1 mmol L^?1), 10^?3 mol L^?1 RLA reduced glucose production by ～ 53% and lactate uptake by ～ 60%, but stimulated bile secretion by ～ 50% (P < 0.05). Conclusion: RLA reduces hepatic glucose release by inhibiting lactate‐dependent glucose production in a concentration‐dependent fashion.     

HMGB1/RAGE信号通路参与尼古丁调控支气管上皮细胞TGF-β1和FGF-2的分泌

目的本研究旨在探讨尼古丁是否通过高迁移率族蛋白1(HMGB1)/晚期糖基化终产物受体(RAGE)信号通路调控支气管上皮细胞转化生长因子β1(TGF-β1)和成纤维细胞生长因子2(FGF-2)的分泌。方法尼古丁(6×10^-6 mol/L)刺激支气管上皮细胞株16HBE,采用酶联免疫吸附测定法(ELISA)检测刺激24 h后细胞中HMGB1、TGF-β1和FGF-2分泌,Western blotting方法检测RAGE表达。预先加入HMGB1 siRNA孵育48 h或RAGE中和抗体孵育1 h,再加入尼古丁刺激16HBE 24 h,ELISA法检测HMGB1、TGF-β1和FGF-2的分泌,Western blotting方法检测RAGE的表达。结果尼古丁刺激24 h后HMGB1的分泌和RAGE的表达量较未予尼古丁刺激的正常对照组明显增加,TGF-β1和FGF-2的分泌量也显著增加。加入HMGB1 siRNA后尼古丁刺激24 h组,HMGB1的分泌量较单纯尼古丁刺激组明显减少,RAGE的表达量显著减少,同时TGF-β1和FGF-2的分泌量较单纯尼古丁刺激组显著减少。加入RAGE中和抗体后尼古丁刺激24 h组,TGF-β1和FGF-2的分泌量较单纯尼古丁刺激组显著减少。结论HMGB1/RAGE信号通路参与了尼古丁调控支气管上皮细胞TGF-β1和FGF-2的分泌。     

More patients reach glycaemic control with a fixed‐ratio combination of insulin glargine and lixisenatide (iGlarLixi) than with basal insulin at 12 weeks of treatment: A post hoc time‐to‐control analysis of LixiLan‐O and LixiLan‐L

The present post hoc analysis of two 30‐week clinical trials compared efficacy and hypoglycaemia outcomes at early study visits with iGlarLixi (insulin glargine U100 [iGlar] and lixisenatide) vs iGlar alone in patients with type 2 diabetes (T2D) uncontrolled on oral antidiabetic drugs (OADs; LixiLan‐O trial) or basal insulin (LixiLan‐L trial). Time to control, defined as days to achieve glycated haemoglobin (HbA1c) <53 mmol/mol (<7%) or fasting plasma glucose (FPG) ≤7.2 mmol/L, was estimated using the Kaplan–Meier method. In the LixiLan‐O and LixiLan‐L trials, 60% and 46% of patients, respectively, reached HbA1c <53 mmol/mol (<7%) with iGlarLixi at 12 weeks, vs 45% and 24%, respectively, with iGlar. In the LixiLan‐O trial, the median time to target HbA1c was approximately half with iGlarLixi vs iGlar (85.0 vs 166.0 days; P < .0001). In the LixiLan‐L trial, the median time to target HbA1c was 153.0 days with iGlarLixi, while target HbA1c was never reached by 50% of patients with iGlar (P < .0001). Time‐to‐target FPG and hypoglycaemia outcomes were similar between treatments. In T2D uncontrolled on OADs or basal insulin, iGlarLixi resulted in glycaemic control in more patients than did iGlar at early treatment time points.