bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of Drp1-Mediated Mitochondrial Fission Protects Diabetic Heart against Ischemia-Reperfusion Injury
Authors: DING MINGGE , FENG JIAHAO , LI ZEYANG , FU FENG
Published: June 2018

Identify the molecular basis linking diabetes with MI/R injury is scientifically important and may provide effective therapeutic approaches. Recent studies indicated that enhanced Dynamin-related protein 1 (Drp1)-mediated mitochondrial fission is involved in both diabetic hearts and ischemic hearts. We hypothesized that inhibition of Drp1-mediated mitochondrial fission may be effective to reduce MI/R injury in diabetic hearts. High-fat diet and streptozotocin-induced diabetic mice were subjected to MI/R or sham operation. Mdivi-1 (1.2 mg/kg), a small molecule inhibitor of Drp1 or vehicle was administrated 15 min before the onset of reperfusion. Outcome measures included mitochondrial morphology, mitochondrial function, myocardial injury, cardiac function and oxidative stress. Mitochondrial fission was significantly increased following MI/R as evidenced by enhanced translocation of Drp1 to mitochondria and decreased mitochondrial size. Delivery of Mdivi-1 into diabetic mice markedly inhibited Drp1 translocation to the mitochondria and reduced mitochondrial fission following MI/R. Inhibition of Drp1-mediated mitochondrial fission increased mitochondrial complex I/II/III/IV activities and ATP content and improved cardiac function following MI/R (n = 8, P < 0.01). Moreover, inhibition of Drp1 reduced myocardial infarct size (28.7 ± 4.2% vs. 45.3 ± 4.7% n = 8, P < 0.01) and serum cardiac troponin and lactate dehydrogenase activities. These cardioprotective effects were associated with decreased cardiomyocyte apoptosis and malondialdehyde production and increased activities of antioxidant enzyme manganese superoxide dismutase (n = 8, P < 0.01). These data suggest that Drp1-mediated mitochondrial fission may be a potential novel therapeutic target for diabetic cardiac complications.

Disclosure

M. Ding: None. J. Feng: None. Z. Li: None. F. Fu: None.
Effects of Glucose and Blood Pressure Variability on Oxidative Stress in Type 2 Diabetes with Hypertension
Authors: OHARA MAKOTO , NAGAIKE HIROE , YAMAMOTO TAKESHI , HAYASHI TOSHIYUKI , FUKUI TOMOYASU , HIRANO TSUTOMU
Published: June 2018

Aims: This study was performed to evaluate the effects of glucose variability (GV) and blood pressure variability (BV) on oxidative stress in type 2 diabetes patients with hypertension.

Methods: Fifty-seven inpatients with type 2 diabetes (studied from May 2015 to august 2017) underwent continuous glucose monitoring (CGM) and ambulatory BP monitoring (ABPM) in a cross-sectional study. The plasma total oxidant capacity against N,N-diethylparaphenylendiamine was measured as a marker of oxidative stress using the d-ROMs test. The GV, mean glucose level (MGL), mean amplitude of glycemic excursions (MAGE), and area under the postprandial plasma glucose curve (AUCPP) were measured by CGM. The BV, mean blood pressure (MBP), max blood pressure (MaxBP), minimum blood pressure (MinBP), and standard deviation of blood pressure (BPSD) during the systole (S) and diastole (D) were measured by ABPM over daytime (day), nighttime (night), and 24-hour (24) periods.

Results: The 57 participants were 65.3±12.9 years old, with a disease duration of 14.7±12.4 years and HbA1c of 8.5±1.2 %. In univariate analysis, MAGE (r=0.446,p<0.001), night DBPSD (r=0.323,p=0.014), and eGFR (r=0.287, p=0.030) were significantly correlated with the d-ROMs. In the stepwise multiple regression analysis, MAGE (β=0.344, t=3.075, p=0.003), night DBPSD (β=0.230, t=2.034, p=0.047), eGFR (β=-0.234, t=-2.137, p=0.037), and smoking (β=0.315, t=2.873, p=0.006) were identified as independent factors contributing to the d-ROMs (multiple R2 = 0.363).

Conclusions: Daily glucose variability and nighttime systolic blood pressure variability are associated with oxidative stress in type 2 diabetes with hypertension.

Disclosure

M. Ohara: None. H. Nagaike: None. T. Yamamoto: None. T. Hayashi: None. T. Fukui: None. T. Hirano: Speaker's Bureau; Self; Novo Nordisk Inc., AstraZeneca.
Relationship between Sleep Disordered Breathing during Rapid Eye Movement Sleep and Coronary Risk Factors in Patients with Type 2 Diabetes Mellitus
Authors: UCHIDA TAKAYASU , NISHIMURA AKIHIRO , KIKUNO SHOTA , NAGASAWA KAORU , OKUBO MINORU , KASAI TAKATOSHI , NARUI KOJI , MORI YASUMICHI
Published: June 2018

Sleep disordered breathing (SDB) is associated with hypertension, poor glycemic control and dyslipidemia. In general, apnea events are more prominent during rapid eye movement (REM) sleep than non-REM (NREM) sleep. Reportedly, only REM-AHI is associated with hypertension and HbA1c. We examined which SDB parameters are associated with BP, HbA1c and lipid profile in type 2 diabetes (T2D) patients.

We analyzed 185 T2D patients who underwent polysomnography after excluding patients with pulmonary diseases, central sleep apnea, treated SDB or REM sleep < 30 minutes. We performed multiple linear regression analyses to predict BP, HbA1c and lipid profiles adjusted for known risk factors.

Patients characteristics (mean±SD/median(IQR)): age 58.0 ± 11.8 yo, BMI 26.0 (24.1-28.9) kg/m2, systolic BP 134 ± 19.1 mmHg, mean BP 97.5 ± 13.8 mmHg, HbA1c 7.4 (6.8-8.4) %, TG 143 (97-195) mg/dL, non-HDL cholesterol 143 (120-163) mg/dL, REM-AHI 35.1 (21.1-53.1) /h. The analyses revealed REM-AHI was independently associated with systolic and mean BP whereas NREM-AHI was not (Fig. 1). No statistically significant association was observed between REM-AHI and HbA1c or lipid profile.

REM-AHI was associated with systolic and mean BP in T2D patients. BP alteration associated with SDB during REM sleep may be an important pathophysiology linking between SDB and cardiovascular diseases.

Disclosure

T. Uchida: None. A. Nishimura: None. S. Kikuno: None. K. Nagasawa: None. M. Okubo: None. T. Kasai: None. K. Narui: None. Y. Mori: None.
Next Generation of Spontaneous Diabetic Model of ZDSD Rats with Intact Leptin Signaling Develop Cardiac Dysfunction and Compromised Cardiac Reserve
Authors: SUN GAO , ZHANG GUODONG , WANG YIXIN
Published: June 2018

Introduction: Cardiomyopathy is the leading cause of morbidity and mortality among all complications of type 2 diabetic (T2D) and obese patients. Diabetic cardiomyopathy (DC) is characterized by an initial cardiac hypertrophy followed by thinning of the cardiac walls with declines in both systolic and diastolic functions, which ultimately leads to heart failure. No rodent models fully captured phenotypes of DC. The ZDSD rat, a new generation of T2D rat model with intact leptin signaling features with slow onset of diabetes and obesity, which closely mimics the development of the disease in patients. Here we sought to evaluate the cardiac function during the development of metabolic syndromes in ZDSD rats.

Methods: 12 male ZDSD rats and age-matched SD controls were monitored for blood pressure, glucose, and cardiac function using echocardiography. Animals were also challenged with 1 mg/kg dobutamine for the assessment of cardiac reserve.

Results: ZDSD rats developed hypertension from age of 18 weeks. Their left ventricular (LV) functions were compromised along with changes in cardiac morphology. At resting state, ZDSD rats showed LV hypertrophy from age of 18 to 22 weeks after which cardiac walls became thinner with larger LV volume. At 34 weeks old, both ejection fraction (EF) and transmitral E/A ratio declined. Upon treatment with dobutamine for 5 minutes, SD rats reached almost 98% EF, while the values of ZDSD were 91% at 30 and 34 weeks old, suggesting the loss of LV contractility the animals.

Conclusion: ZDSD rats which carry multiple dysmetabolic phenotypes are spontaneously hypertensive with reduction in LV function and cardiac reserve which resembles ultrasonic symptoms of diabetic cardiomyopathy patients. Therefore, ZDSD rats may serve as a suitable preclinical model to study potential therapeutic approaches to treat cardiomyopathy with presence of metabolic syndromes.

Disclosure

G. Sun: None. G. Zhang: None. Y. Wang: None.
Skin Autofluorescence, a Marker of Glycaemic Memory in Type 2 Diabetes
Authors: MARINE RIGO , MARIE MONLUN , MOHAMMEDI KAMEL , BLANCO LAURENCE , RIGALLEAU VINCENT
Published: June 2018

Glycaemic memory is defined as the deferred consequences of prior hyperglycaemic exposition on the risk of complications. The accumulation of advanced Glycation End products, assessed by the skin autofluorescence (AF), may explain this phenomenon. We evaluated the associations of AF with HbA1c and vascular complications in patients with type 2 diabetes (T2D). We assessed previous HbA1c from the last 120 months (median [IQR] 14 [4, 30]) and the history of vascular complications in T2D patients. The skin AF was measured using an AGE Reader. Association between prior HbA1c and AF tertiles was tested using a mixed regression model with random effects after multiple adjustments. To test the glycaemic memory, analyses were stratified by rising interval time of HbA1c measurements: recent (3 [2, 4]), medium (14 [12, 18]), and old (36 [30, 60] months). The association between AF tertiles and complications was tested by logistic regression model. We collected 2485 HbA1c (mean±SD 8.9±1.9%) measurements in 9patients: 57% men, age 62±10 years, diabetes duration 14±10 years. AF was 2.67±0.66 AU. The highest main [95% CI] HbA1c was observed in the upper AF tertile: T1 8.8 [8.6-9.0], T2 8.9 [8.7-9.1], T3 9.1 [8.9-9.3], p=0.03. This association was greater in patients with the oldest HbA1c measurements: T1 8.4 [8.0-8.9], T2 8.9 [8.4-9.3], T3 9.3 [8.8-9.8], p=0.002. Micro- and macrovascular diseases were observed in 577 and 316 patients, respectively. AF was higher in participants with microvascular (2.79±0.67 vs. 2.46±0.57, p<0.0001) and macrovascular complications (2.78±0.66 vs. 2.61±0.65, p=0.0004) compared to others. Microvascular (T2 vs. T1, OR [95% CI] 1.39 [0.88-2.18], p=0.16; T3 vs. T1 2.20 [1.38-3.57], p=0.001) and macrovascular disease (1.51 [1.02-2.22], p=0.03; 0.99 [0.66-1.49], p=0.96) were associated with the upper AF tertiles in the adjusted model. A high AF was associated with a high HbA1c during the 5 previous years, and related to vascular complications: 2 criteria for being a glycaemic memory marker in T2D patients.

Disclosure

R. Marine: None. M. Marie: None. K. Mohammedi: Speaker's Bureau; Self; Novo Nordisk Inc.. Other Relationship; Self; Novo Nordisk Inc.. Speaker's Bureau; Self; Sanofi. Other Relationship; Self; Sanofi, Takeda Development Centre Europe Ltd., Boehringer Ingelheim Pharmaceuticals, Inc.. L. Blanco: None. V. Rigalleau: None.
Association between Arterial Stiffness and Cardiovascular Autonomic Neuropathy in Youth with Type 2 Diabetes—SEARCH for Diabetes in Youth Study
Authors: JAISWAL MAMTA , DIVERS JASMIN , DABELEA DANA , LAWRENCE JEAN M. , KIM GRACE , LIESE ANGELA D. , URBINA ELAINE M.
Published: June 2018

Accelerated vascular aging in youth with type 2 diabetes (T2D) makes them vulnerable for a cardiovascular event in early adulthood. We explored the relationship between increased arterial stiffness (AS) and reduced heart rate variability (HRV) in youth with T2D.

193 youth with T2D (age 22 ± 4 years, duration 8 ± 2 years, HbA1c 8.9 ± 4.4%, 40% non-Hispanic black) enrolled in the SEARCH study had PWV (pulse wave velocity carotid-femoral segment) and HRV [standard deviation (SDNN) and root mean square successive difference(RMSSD) of normal RR interval] assessed. AS+ was defined as the PWV > 90th percentile for age and gender-matched healthy controls.

Youth with increased AS were older, had higher blood pressure (BP), BMI, triglycerides and lower HDL-c (P ≤ 0.05) (Table). In linear regression analysis, increased PWV was associated with lower SDNN independent of age, gender, race/ethnicity, BP and BMI (β= -0.03, SE=0.02, P=0.04). However, the association was attenuated and non-significant when controlled for triglyceride suggesting that the relationship between AS and HRV is mediated partly by dyslipidemia.

TABLE 1. Characteristics of the youth with type 2 diabetes stratified by their arterial stiffness (AS) statusVariableAS –AS +P-valueAge, years22 ± 423 ± 40.008Systolic Blood Pressure, mm Hg115 ± 10121 ± 11<0.001BMI z-score1.9 ± 0.42.4 ± 0.37<0.001HDL-cholesterol, mg/dL43 ± 939 ± 90.002Triglycerides, mg/dL104 (73,175)139 (87,248)0.02HbA1c, %8.7 ± 4.49.5 ± 4.10.28SDNN, msec52(36,79)42(29,62)0.003

Early subclinical atherosclerosis was associated with cardiovascular autonomic neuropathy in young people with T2D which could potentially increase the risk of early cardiovascular events. Interventions targeting the risk factors for AS and CAN are needed.

Disclosure

M. Jaiswal: None. J. Divers: None. D. Dabelea: None. J.M. Lawrence: None. G. Kim: None. A.D. Liese: None. E.M. Urbina: None.
Roles of Histone Deacetylases in Arteriovenous Fistula Failure Under Disturbed Flow
Authors: CHIU JENG-JIANN , YANG TUNG-LIN
Published: June 2018

Chronic kidney disease, which affects 11.9% of adults and its prevalence of the end-stage renal disease (ESRD) is highest in Asia, is a major health problem in the world. More than 90% of the ESRD patients receive hemodialysis, with the creation of hemodialysis vascular access (HVA), including arteriovenous fistula (AVF). Although AVF is the preferred form of permanent hemodialysis access, it still remains significant problems, such as thrombosis, stenosis and vascular access infections. AVF operation has been shown to change hemodynamic environments. However, the relationship between hemodynamic factors and AVF failure remains unclear. By using Doppler ultrasound to detect the flow patterns in human patients with AVF and rat AVF models, we found that flow disturbance with high and oscillatory shear stress (HOSS, ∼30±100 dynes/cm2) is generated in the anastomotic site of AVF. Venous endothelial cells (ECs) in regions of anastomosis showed higher expression of class I histone deacetylases (HDAC-1/2/3) and lower expression of thrombomodulin (TM) in both human patients and rat AVF models in comparison to control subjects. We further developed in vitro flow system to generate HOSS at 30±100 dyne/cm2 and laminar shear stress (LSS) at 5 dyne/cm2 to mimic flow patterns in the pathophysiological and physiological flow environments of human AVF, respectively. Application of HOSS to venous ECs induces the association of HDAC-3 with krüppel-like factor 2 (KLF2) to deacetylate KLF2, resulting in the down-regulation of TM. Intraperitoneal administration of valproic acid (VPA), which is a specific inhibitor of class I HDACs, into AVF rats inhibits the increased formation of stenosis at anastomotic sites. Our findings demonstrate that flow disturbance with HOSS can induce HDAC-3 to deacetylate KLF2 and repress TM, and hence contribute to AVF stenosis and failure. Such information may help to generate new approaches for therapeutic interventions against inflammation and thrombosis in AVF in patients.

Disclosure

J. Chiu: None. T. Yang: None.
Insulin Deficiency Is a Major Contributor to Atrial Fibrillation
Authors: MARIA ZAHRA , CAMPOLO ALLISON , SCHERLAG BENJAMIN J. , RITCHEY JERRY W. , LACOMBE VERONIQUE
Published: June 2018

Diabetes has been identified as a major independent risk factor for atrial fibrillation (AF), the most common sustained cardiac arrhythmia. However, it is unknown whether glucose and insulin disturbances observed during diabetes directly affect the function of the atria, leading to AF. Thus, we hypothesized that insulin deficiency and impaired glucose transport provide a metabolic substrate for the development and maintenance of AF during diabetes. Transesophageal atrial pacing was used to induce AF in healthy, streptozotocin-induced type 1 diabetic and insulin-treated (via a subcutaneous pump) diabetic mice (n=4-11/group). Translocation of insulin-sensitive glucose transporters (GLUTs) was measured using a photolabeled biotinylation assay in the perfused heart. Atrial fibrosis and glycogen accumulation were measured using histological analyses. As expected, insulin-deficient diabetic mice displayed hyperglycemia (434 ± 50.9 mg/dl) while insulin-treated diabetic mice remained euglycemic (118.8 ± 3.3 mg/dl, p<0.05). At 8 weeks, diabetic mice displayed increased duration and frequency of AF episodes vs. age-matched controls (e.g., AF duration: 18.7 ± 6.2 s vs. 1.8 ± 1.1 s, respectively, p=0.032), whereas insulin-treated diabetic animals did not. In addition, the frequency of AF episodes was significantly correlated to blood glucose level (p=0.01). GLUT-4 and -8 translocation to the atrial cell surface was significantly downregulated in diabetic mice (by 67% and 79%, respectively; p≤0.001), and rescued by insulin treatment. We did not observe any fibrosis or glycogen accumulation in the atria of (treated and untreated) diabetic mice. We conclude that, in the absence of structural remodeling and atrial fibrosis, insulin and glucose disturbances were sufficient to induce AF during diabetes. Therefore, these data suggest that insulin deficiency during diabetes leads to alterations in glucose transport and energy production in the atria, which enhances its vulnerability to atrial fibrillation.

Disclosure

Z. Maria: None. A. Campolo: None. B.J. Scherlag: None. J.W. Ritchey: None. V. Lacombe: None.
Impact of Type 2 Diabetes Mellitus and Myocardial Perfusion on Long-Term Risk of Heart Failure and All-Cause Mortality following Interventional Treatment of ST-Elevation Myocardial Infarction
Authors: TOMASIK ANDRZEJ , NABRDALIK KATARZYNA , KWIENDACZ HANNA , SAWCZYN TOMASZ , KUKLA MICHAL , RADZIK EDYTA , PIGON KATARZYNA , MłYńCZAK TOMASZ , GUMPRECHT JANUSZ , GRZESZCZAK WLADYSLAW , NOWALANY-KOZIELSKA EWA
Published: June 2018

Patients with type 2 diabetes mellitus (T2DM) who undergo primary percutaneous coronary intervention (pPCI) for ST-elevation myocardial infarction (STEMI) have worse myocardial perfusion than normoglycemic patients. It is not known whether these factors combined influence prognosis in term of heart failure (HF) and/or all-cause mortality. We aimed to evaluate the impact of T2DM and myocardial perfusion on long-term risk of HF and/or all-cause mortality following interventional treatment of STEMI. 4STEMI patients (104 with T2DM) treated with pPCI were enrolled into the study. Myocardial perfusion was reassessed with: myocardial blush grade (MBG), Quantitative myocardial Blush Evaluator (QuBE), resolution of ST-segment elevation (STR). Follow-up data was collected during 6 years. 23.1% patients with T2DM developed HF vs. 16.9% without T2DM (P=NS). 34.6% of patients with T2DM have died vs. 14.9% patients without T2DM (P=0.000). Patients with T2DM and HF have had the highest mortality rate of 75%. Survival of patients with T2DM in relation to QuBe score is presented in the Figure. There was no difference in myocardial perfusion assessed by STR. T2DM and diminished myocardial perfusion increase the risk of HF and/or all cause death in 6 years follow-up.

Disclosure

A. Tomasik: None. K. Nabrdalik: None. H. Kwiendacz: None. T. Sawczyn: None. M. Kukla: None. E. Radzik: None. K. Pigon: None. T. Młyńczak: None. J. Gumprecht: Speaker's Bureau; Self; AstraZeneca. Consultant; Self; Bayer AG. Speaker's Bureau; Self; Bioton, Berlin-Chemie AG, Eli Lilly and Company, Merck Sharp & Dohme Corp., Boehringer Ingelheim GmbH, Novo Nordisk A/S, Polfa Tarchomin S.A., Polpharma. W. Grzeszczak: Speaker's Bureau; Self; Boehringer Ingelheim GmbH, Bioton, Merck & Co., Inc., Novo Nordisk A/S. Stock/Shareholder; Self; Eli Lilly and Company. Speaker's Bureau; Self; Bayer AG. E. Nowalany-Kozielska: None.
Association of Serum Sestrin2 Level with Metabolic Risk Factors in Newly Diagnosed Drug-Naïve Type 2 Diabetes
Authors: CHUNG HYE SOO , ROH EUN , HONG SO-HYEON , KIM JUNG A. , LEE YOU-BIN , BAIK SEI HYUN , CHOI KYUNG MOOK , YOO HYE JIN
Published: June 2018

Objective: Previous in vitro and in vivo experimental studies have shown that Sestrin2 attenuates oxidative stress and the pro-inflammatory pathway, resulting in improving metabolic homeostasis. However, the relationship between circulating Sestrin2 concentration and cardiometabolic risks in humans has not been explored.

Methods: Sestrin2 concentration was measured in 240 subjects (46 nondiabetics and 194 diabetics) using an enzyme-linked immunosorbent assay, and the associations between Sestrin2 level and various cardiometabolic risk factors including body composition, insulin resistance, and atherosclerosis was assessed.

Results: Sestrin2 concentration showed a trend of increasing in subjects with metabolic syndrome. After adjustment for age and gender, Sestrin2 level had a positive relationship with serum triglyceride, alanine aminotransferase (ALT), and creatinine levels, but no association with carotid atherosclerosis. Especially, in subjects with type 2 diabetes Sestrin2 concentration exhibited a significant positive correlation with body mass index (P =0.015), waist circumference (P =0.020), high-sensitivity C-reactive protein (P =0.008), Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) (P =0.041), percentage body fat (P =0.001), and truncal fat mass (P =0.005) after adjusting age and gender. Multiple stepwise regression analysis identified age, serum ALT and creatinine levels, and percentage body fat as independent determining factors for Sestrin2 concentration in patients with type 2 diabetes (R2 = 0.173).

Conclusions: This study is the first to demonstrate a trend for increased Sestrin2 level in subjects with metabolic syndrome. In particular, in subjects with type 2 diabetes, Sestrin2 was significantly related to insulin resistance and percentage body fat, suggesting its potential as a novel modulatory factor for metabolic disorders in humans.

Disclosure

H. Chung: None. E. Roh: None. S. Hong: None. J.A. Kim: None. Y. Lee: None. S. Baik: None. K. Choi: None. H. Yoo: None.
Intermittent Hypoxia Induces Expression of Epiregulin mRNA via Upregulation of Interleukin-6 in Human Coronary Artery Smooth Muscle Cells
Authors: KYOTANI YOJI , ZHAO JING , ITAYA-HIRONAKA ASAKO , YAMAUCHI AKIYO , SAKURAMOTO-TSUCHIDA SUMIYO , MAKINO MAI , TAKASAWA SHIN , YOSHIZUMI MASANORI
Published: June 2018

Sleep apnea syndrome (SAS) is characterized by repetitive episodes of oxygen desaturation and re-saturation, such as intermittent hypoxia (IH), and well known as an independent risk factor for diabetes and atherosclerosis. We previously showed that IH directly induced the proliferation of cultured rat aorta smooth muscle cells through upregulations of epidermal growth factor family, especially epiregulin (EREG), and their erbB2 receptor. However, its underlying mechanism remains unclear. On the other hand, we also reported that IH increased interleukin (IL)-6 mRNA in pancreatic beta cells. In this study, we investigated the influence of IH on IL-6 production, and the impact of IL-6 on the expression of EREG, using human coronary artery smooth muscle cells (hCASMC) and in vitro IH system. Quantitative RT-PCR revealed that EREG mRNA was significantly increased by IH, but not by sustained hypoxia. IH also increased expression of IL-6 mRNA in IH cycle dependent manner (3∼72 cycles in 1∼24 hours). Mature IL-6 increased in IH-exposed cell conditioned medium as similar time-dependent manner as seen in mRNA. We next investigated whether IL-6 increases the expression of EREG mRNA in hCASMCs. The addition of IL-6 (100 ng/mL) induced a significant upregulation of EREG mRNA expression. Taking into account the IH-induced increase of IL-6 and IL-6-induced upregulation of EREG mRNA in hCASMCs, we hypothesized that elevated IL-6 production due to IH was responsible for the IH-induced increase in EREG mRNA. To determine the direct role of IL-6 in IH-induced increases in EREG mRNA expression, we applied siRNAs for IL-6 and the IL-6 receptor and obtained the result that both siRNAs for IL-6 and IL-6 receptor significantly suppressed the IH-induced increase of EREG mRNA. These results indicated that IL-6 plays a pivotal role in EREG upregulation by IH and consequently OSA-related atherosclerosis.

Disclosure

Y. Kyotani: None. J. Zhao: None. A. Itaya-Hironaka: None. A. Yamauchi: None. S. Sakuramoto-Tsuchida: None. M. Makino: None. S. Takasawa: None. M. Yoshizumi: None.
ROCK2 Regulates the Expression of Cell Adhesion Molecules and Cell-to-Cell Adhesion in Vascular Endothelial Cells
Authors: TAKEDA YUSUKE , MATOBA KEIICHIRO , KAWANAMI DAIJI , NAGAI YOSUKE , AKAMINE TOMOYO , ISHIZAWA SHO , KANAZAWA YASUSHI , YOKOTA TAMOTSU , UTSUNOMIYA KAZUNORI
Published: June 2018

A pro-inflammatory lipid mediator, lysophosphatidic acid (LPA), is a potent activator of the RhoA/Rho kinase signaling pathway and has been shown to induce the expression of cell adhesion molecules (CAMs). LPA levels are elevated in the circulation of patients with acute coronary syndrome and has also been described inside human atherosclerotic specimens. However, the involvement of Rho-kinase isoforms (i.e., ROCK1, ROCK2) in LPA-mediated expression of CAMs in endothelial cells is not fully understood. In this study, we investigated isoform-specific roles of Rho-kinase in LPA-mediated E-selectin expression using human aortic endothelial cells (HAEC). Exposure of HAEC to LPA resulted in an increase of E-selectin expression at both mRNA (real-time PCR) and protein (Western blot) levels. We confirmed increased Rho-kinase activity in the LPA-stimulated cells. Y-27632, a specific Rho-kinase inhibitor, completely abolished E-selectin protein expression, indicating that LPA induces E-selectin expression via Rho-kinase activation. LPA-induced E-selectin gene expression was strongly suppressed by a chemical inhibitor of NF-κB, indicating the contribution of NF-κB transactivation in this pathway. Intriguingly, phosphorylation of NF-κB RelA/p65 was decreased by Rho-kinase inhibition in the LPA-stimulated cells. Furthermore, using isoform specific siRNAs, we found that Rho-kinase isoform ROCK2 is the key mediator of LPA-induced E-selectin expression and cell adhesion between HAECs and human monocytic cells (THP-1). In the present study, we demonstrate that ROCK2 mediates LPA-induced expression of E-selectin via NF-κB signaling in endothelial cells. ROCK2 could be an important therapeutic target against atherosclerosis.

Disclosure

Y. Takeda: None. K. Matoba: None. D. Kawanami: None. Y. Nagai: None. T. Akamine: None. S. Ishizawa: None. Y. Kanazawa: None. T. Yokota: None. K. Utsunomiya: None.
Diabetes-Induced Vascular Dysfunction Can Be Attenuated with a Naked G7 Polyamidoamine Dendrimer In Vivo
Authors: AKHTAR SAGHIR , CHANDRASEKHAR BINDU , EL-HASHIM AHMED Z. , BENTER IBRAHIM
Published: June 2018

Upregulation of epidermal growth factor receptor (EGFR) signaling is involved in development of diabetes-induced vascular dysfunction. Polyamidoamine (PAMAM) dendrimers (branch-like polymers) might be novel inhibitors of EGFR for they inhibit EGFR phosphorylation in vitro. Here, we investigated whether chronic administration of a generation (G) 7 PAMAM dendrimer could have beneficial effects on diabetes-induced vascular dysfunction by inhibiting EGFR signaling in a model of type 1 diabetes. Dendrimer administration (daily i.p for up to 4 weeks) to Male Wistar rats bearing streptozotocin-induced diabetes dose- and time-dependently inhibited EGFR-ERK1/2-ROCK signaling- a key pathway in the development of diabetic vascular complications. Dendrimer-induced inhibition of EGFR signaling correlated well with a significant correction in hyper-responsiveness of the diabetic mesenteric vascular bed to norephinephrine- a routinely used experimental measure of vascular dysfunction. The dendrimer also inhibited high glucose-induced EGFR-ERK1/2-ROCK signaling in primary vascular smooth muscle cells grown in high (25mM) glucose. These data show for the first time that a PAMAM dendrimer administered chronically in vivo can lead to inhibition of EGFR-ERK1/2-ROCK signaling and attenuate diabetes-induced vascular dysfunction in an experimental model of diabetes.

Disclosure

S. Akhtar: None. B. Chandrasekhar: None. A.Z. El-Hashim: None. I. Benter: None.
NMR-Based Lipidomic Analysis of Red Blood Cells Membranes in Type 2 Diabetes
Authors: KOSTARA CHRISTINA , BAIRAKTARI ELENI , ELISAF MOSES , TSIMIHODIMOS VASILEIOS
Published: June 2018

Changes in the composition of red blood cells membranes may lead to in an altered blood rheological pattern. Experimental studies suggest that hyperglycemia affects red cell rheology via direct effects on the membrane, including alterations of the lipid membrane bilayer composition and microviscosity and changes in membrane Na+/K+ ATP-ase function.

We aimed to investigatate the 1H NMR-based lipid profile of RBC membranes in type 2 diabetic patients and compare it to that of nondiabetic subjects.

Blood samples from 25 nondiabetic and 15 diabetic individuals were collected after an overnight fast. The groups were matched for age, sex and conventional lipid parameters. RBC were lysed and their lipid content was extracted according to a standard procedure. The lipid profile of membranes was recorded on Bruker DRX-500 NMR Spectrometer and analyzed by multivariate data techniques.

The NMR-based lipidomic analysis showed that diabetic patients presented a significantly different lipid profile in RBC membranes compared to that recorded in nondiabetic individuals. RBC membranes from patients with diabetes were characterized by altered fatty acid pattern e.g., higher saturated and lower unsaturated fatty acid levels and lower concentrations of omega-3 fatty acids, mainly docosahexaenoic acid. In addition, lower levels of phosphatidylcholine and phosphatidylethanolamine, and higher levels of sphingomyelin and cholesterol were observed in diabetic patients compared to nondiabetic individuals.

In conclusion, the lipid composition of RBC membranes in the diabetic state is significantly altered. These disturbances may be involved in the pathogenesis of the microvascular complications of diabetes through the disruption of tissue delivery of oxygen. Additionally, the increased cholesterol content of red cell membranes that reach the lipid core of the atherosclerotic plaques through the vasa vasorum may lead to core expansion, decrease their stability and make them prone to rupture.

Disclosure

C. Kostara: None. E. Bairaktari: None. M. Elisaf: None. V. Tsimihodimos: None.
Association between Glycated Lipoproteins and Vascular Function in African-American Diabetic Patients
Authors: ELUWOLE AYOBAMI , ADEDAYO AJIBOLA M. , TEDLA FASIKA , KREMER ARYE , MASTROGIOVANNI NICOLE , ROSENBERG CARL , DREIZEN PAUL , LAROSA JOHN , SALCICCIOLI LOUIS , BOUTJDIR MOHAMED , BANERJI MARY ANN , BROWN CLINTON , SALIFU MORO , LAZAR JASON , BAKILLAH AHMED
Published: June 2018

Patients with type 2 diabetes mellitus exhibit non-enzymatic glycation of lipoproteins that are considered proatherogenic modification contributing to increased susceptibility of patients with diabetes to atherosclerosis. We postulated that glycated lipoproteins might be associated with vascular outcome. To explore this, we studied the relationship between glycated HDL (gHDL) and glycated LDL (gLDL) with vascular function in African American diabetic patients. Total of 146 diabetic were enrolled over a 6 month period. Levels of plasma gHDL and gLDL were measured by enzyme-linked immunosorbent assay (ELISA). Microvascular function was assessed by vascular reactivity index (VRI). Large artery stiffness was assessed by carotid-femoral pulse wave velocity (PWV). Carotid intima-media thickness (C-IMT) was assessed by B-mode ultrasound image analysis. Mean patient age was 60±8 years, 64% were female. 80% had hypertension, 90% had dyslipidemia and 15% had chronic kidney disease. Mean HbA1c levels were 8.1±2.2%. Pearson correlation analysis showed no significant correlation between gHDL and gLDL. Multi-regression analysis revealed that gHDL was negatively associated with VRI (β= -0.006, p= 0.012; r2 = 0.276 for model) in the entire population and in the group of patients with good glycemic control (HbA1c ≤ 7.0; β= -0.007, p= 0.031; r2 = 0.312 for model); whereas gLDL was positively associated with CIMT (β= 0.045, p= 0.051; r2= 0.568 for model) after adjustment for other independent variables such as age, gender, stroke, smoking, hypertension, dyslipidemia, HbA1c, diabetes duration, HDLc, and LDLc.

In this cohort, data showed that gHDL was associated with microvascular function, whereas gLDL was mainly correlated with carotid intima media thickness. Further large study is needed to clarify mediating factors of these relationships.

Disclosure

A. Eluwole: None. A.M. Adedayo: None. F. Tedla: None. A. Kremer: None. N. Mastrogiovanni: None. C. Rosenberg: None. P. Dreizen: None. J. LaRosa: None. L. Salciccioli: None. M. Boutjdir: None. M. Banerji: Speaker's Bureau; Self; Merck & Co., Inc.. C. Brown: None. M. Salifu: None. J. Lazar: None. A. Bakillah: None.
Real-World Implementation of Hybrid Closed-Loop (HCL) Insulin Delivery
Authors: FAULDS EILEEN R. , DUNGAN KATHLEEN M.
Published: June 2018

Objective: Clinical trials demonstrate improved glycemic control with HCL insulin delivery systems, yet limited real-world data exists substantiating these findings. Data from the inaugural cohort of patients initiating a HCL system (Medtronic 670G) at a university medical center was used to examine real-world utilization, adherence, and glycemic control over the first 6-12 weeks of pump use.

Research Design and Methods: Data from 35 patients with type 1 diabetes (22-72 years of age) were obtained from insulin pump downloads at 4 time points: previous insulin pump, HCL start in manual-mode, 2-weeks after auto-mode transition, and between 6-12 weeks after HCL start. In person training by certified diabetes educators was performed for manual-mode, sensor initiation, and auto-mode with phone and electronic messaging following initiation of auto-mode.

Results: A total of 46 patients received HCL between June 1 and December 31 of 2017. Of these, 7 patients did not have sensors allowing them to initiate HCL, 3 did not have a 6-12 week download, and 1 never transitioned into auto-mode. Mean self-monitoring blood glucose (SMBG) per day increased from 5.15 baseline to 6.49 at 6-12 weeks (p<0.05) with 3.26 sensor calibrations per day. Time in auto-mode was 79.3% at 2 weeks, and 71.7% by 6-12 weeks with 82% of patients spending >50% of time in auto-mode. Over the 14-day final download there were 8.2 auto-mode exits. Time in target was 65.5% in manual-mode, 73.4% at 2-weeks (p=0.09), and 71.7% by 6-12 weeks (p=0.06). HbA1C decreased 0.51% (p=0.02), total daily dose increased (p=0.027), while basal-to-bolus ratio did not change over the study period. Baseline mean SMBG and HbA1C, but not basal:bolus ratio, bolus calculator use, or bolus frequency, were significant predictors of time in auto-mode and time-in-target at 6-12 weeks.

Conclusions: These data illustrate real-world implementation of HCL technology within a major medical center. Patients initiating HCL achieved acceptable time-in-auto mode and time-in-target range.

Disclosure

E.R. Faulds: Other Relationship; Self; A1Contro, LLC. K.M. Dungan: Research Support; Self; Novo Nordisk Inc.. Advisory Panel; Self; Sanofi-Aventis. Research Support; Self; Sanofi-Aventis, GlaxoSmithKline plc.. Consultant; Self; GlaxoSmithKline plc.. Research Support; Self; AstraZeneca. Other Relationship; Self; DKBmed, Horizon, Projects in knowledge, Rockpointe.
Identification of Pancreatic Elastase Inhibitors That Can Stimulate Beta-Cell Proliferation
Authors: BASILE GIORGIO , VETERE AMEDEO , HU JIANG , WAGNER BRIDGET , KULKARNI ROHIT
Published: June 2018

The identification of novel small molecules that can target endogenous factors to regulate β-cell proliferation is a desirable goal to counter all forms of diabetes. Recently, we identified serpinB1 (SB1), an endogenous protease inhibitor, as a protein that promotes human β-cell proliferation by inhibiting elastase activity, and demonstrated that the elastase inhibitor sivelestat also induced β-cell proliferation. Here, we report high-throughput screening to identify novel elastase inhibitors and to evaluate their ability to induce human β-cell proliferation. We screened 16,320 compounds using a fluorescence-based porcine pancreatic elastase (pPE) assay, and confirmed inhibition of human neutrophil (hNE) and pancreatic (hPE) elastases using an absorbance-based assay. We observed that telaprevir and tebipenem each inhibited pPE with greater potency than sivelestat (IC50: telaprevir 33.9 nM, tebipenem 1.1 µM, sivelestat 2.4 µM; n=3). The results were confirmed on hPE (IC50: telaprevir 15.7 nM, tebipenem 3.6, sivelestat 2.3 µM; n=3), while neither telaprevir nor tebipenem blocked hNE activity. Interestingly, telaprevir and SB1 inhibited hPE and pPE at similar concentrations, enforcing the hypothesis of a shared mechanism of action between the protein and the compound. We then assessed the mitogenic properties of the compounds in in vitro cultures of mouse and human islets by immunofluorescence. Telaprevir and tebipenem each increased proliferating β-cells in rodent (∼6-fold and 1.5-fold increase, respectively; n=3) and human islets (∼4-fold and 1.5-fold increase, respectively; n=3) compared to vehicle-treated islets. Taken together, these data confirm the identification of two novel compounds with the ability to inhibit pancreatic elastase and enhance mammalian β-cell proliferation. These results highlight the therapeutic potential of using elastase inhibitors to stimulate β-cell proliferation to treat diabetes.

Disclosure

G. Basile: None. A. Vetere: None. J. Hu: None. B. Wagner: None. R. Kulkarni: None.
Hyposialylated Angiopoietin-4 Induces Podocyte Apoptosis via a3ß1 Integrin/FAK Signaling in Diabetic Nephropathy
Authors: CHEN HAIBING , GUO KAIFENG , PAN PAN
Published: June 2018

Podocyte dysfunction, one of the major causes of proteinuria, leads to glomerulosclerosis and end stage renal disease, but its underlying mechanism remains poorly understood. Angptl4 has been reported to mediate proteinuria in some types of glomerulonephropathy. However, the underlying molecular mechanism remains unclear. This study aimed to investigate the role of Angptl4 in the pathogenesis of DN. In this study, we found that expression of ANGPTL4 in the kidney cortex was significantly increased in the diabetic mouse. Moreover, we demonstrated that ANGPTL4 induced podocytes apoptosis and actin cytoskeleton derangement via integrin pathway under high glucose. High glucose increased integrinα3β1 in podocytes. Our results showed ANGPTL4-induced podocytes apoptosis and actin cytoskeleton damage was effectively attenuated by blocking ANGPTL4 and integrin α3β1 by neutralizing antibody in vitro. Furthermore, we demonstrated that the effect of ANGPTL4 on podocyte damage is due to increased podocyte-secreted hyposialylated ANGPTL4 under high glucose, and these effects were effectively attenuated by conversion of hyposialylated ANGPTL4 to its sialylated form with ManNAc in both vivo and vitro. Taken together, these results indicate that targeting Angptl4 related signaling may represent a novel therapeutic strategy for proteinuric kidney diseases.

Disclosure

H. Chen: None. K. Guo: None. P. Pan: None.
Sweet-Taste Receptors Mediated ROS-NLRP3 Inflammasome Signaling Activation—Implications for Diabetic Nephropathy
Authors: ZHOU LUPING , HUANG WEI , XU YONG , GAO CHENLIN
Published: June 2018

Previous studies demonstrated that ROS-NLRP3 inflammasome signaling activation were involved in the pathogenesis of diabetic nephropathy (DN). But the mechanism by which high glucose prime ROS-NLRP3 inflammasome signaling remains debatable. Recent research has shown that taste receptor type 1, member 2 (T1R2) and member 3 (T1R3), form heterodimers to act as sweet taste receptors (STRs), are widely expressed in the extraoral tissues, and emerging evidence suggests that STRs are important sentinels of innate immunity. As a natural ligand for STRs, whether high glucose prime ROS-NLRP3 inflammasome signaling via STRs is unclear. Therefore, diabetes mellitus (DM) mouse model was induced by streptozotocin (STZ) in vivo, mouse glomerular mesangial cells (GMCs) and human proximal tubular cells were stimulated by elevated concentrations of high glucose (10, 20, and 30 mmol/L) or mannitol as the osmotic pressure (OP) control in vitro, STRs inhibitor lactisole were used as an intervention reagent to evaluated the role and mechanism of the STRs in the pathogenesis of DN. Our results showed that the expression of STRs (T1R2 and T1R3) and associated signalling components (Gα-gustducin, PLCβ2, TRPM5) were obviously down-regulated under the condition of diabetes in vivo and in vitro. Further more, lactisole signifcantly mitigated the production of intracellular ROS and reversed the decrease of Ca2+ and the activation of NLRP3 inflammasome signaling in GMCs stimulated by high glucose (p<0.05). These combined results support the hypothesis that high glucose induced ROS-NLRP3 inflammasome signaling activation in part via STRs, suggesting that STRs may act as new therapeutic targets of DN.

Disclosure

L. Zhou: None. W. Huang: None. Y. Xu: None. C. Gao: None.
Backcross db Gene into CD-1 Background Results in Novel Type 2 Diabetic Mouse Model with Progressive Kidney Fibrosis
Authors: MIZUNUMA YUIKO , NITTA KYOKO , TAKAGI SUSUMU , KANASAKI KEIZO , KOYA DAISUKE
Published: June 2018

Kidney fibrosis is the final common pathway of progressive kidney disease including diabetic kidney disease (DKD). With the rapid increase of type 2 diabetes, DKD in type 2 diabetic patients has become a serious public health threat around the world. To establish novel therapy to combat DKD, human disease relevant animal model is essential. However, a type 2 diabetic mouse model with presenting progressive kidney fibrosis is not established yet. We have previously reported that kidneys of streptozotocin-induced diabetic CD-1 mice exhibited severe fibrosis compared to other backgrounds of mice associated with the suppression of anti-fibrotic peptide N-acetyl-seryl-aspartyl-lysyl-proline, fibroblast growth factor receptor 1, and their downstream target anti-fibrotic microRNAs (miRs) such as miR 29 and miR let-7. As the type 2 diabetic mice model, leptin receptor deficient mice in BKS background (BKSdb/db) are often utilized; the kidney fibrosis in BKSdb/db phenotype is minimum. Here we backcrossed db gene into potential fibrotic CD-1 background and found that male CD-1db/db exhibited severe kidney fibrosis when compared to male BKSdb/db. We have already performed the backcrosses for 11 generations. Body weight of CD-1db/db was comparable but drank up to 3 times more water compared to BKSdb/db. Blood glucose levels in CD-1db/db appeared to be higher when compared to BKSdb/db. When evaluated the per body weight ratio, kidney and heart weighed no significant differences between CD-1db/db and BKSdb/db. CD-1db/db exhibited severe tubulo-interstitial fibrosis, glomerulosclerosis, and tubular epithelial cells damage. Heart in CD-1db/db displayed fibrotic change as well.

In conclusion, here we provide novel fibrotic type 2 DKD mouse model. CD-1db/db could be excellent model to perform experimental therapy for DKD.

Disclosure

Y. Mizunuma: None. K. Nitta: None. S. Takagi: None. K. Kanasaki: Advisory Panel; Self; Boehringer Ingelheim Pharmaceuticals, Inc.. Speaker's Bureau; Self; Eli Lilly and Company, Sanofi, Mitsubishi Tanabe Pharma Corporation. Research Support; Self; Boehringer Ingelheim GmbH. Speaker's Bureau; Self; Boehringer Ingelheim GmbH, Astellas, Astellas. Research Support; Self; Ono Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Corporation. D. Koya: None.
Carbohydrate Response Element Binding Protein (ChREBP) Promotes Inflammation and Apoptosis of Mesangial Cells
Authors: CHEN YAN , ZHAO SHUJIE , WANG YANJUN
Published: June 2018

Objective: Diabetic nephropathy (DN) is one of the most devastating complications of diabetes mellitus. Carbohydrate response element binding protein (ChREBP) is a basic helix-loop-helix leucine zipper transcription factor that primarily mediates glucose homeostasis in the body. The present study investigated the role of ChREBP in the pathogenesis of DN.

Materials and Methods: The expression of ChREBP was detected in patients with type 2 diabetes mellitus (T2DM), diabetic mice and mesangial cells. ELISA was used to measure cytokine production in mesangial cells. Flow cytometry analysis was performed to detect the apoptosis of mesangial cells in the presence of high glucose.

Results: The ChREBP and several cytokines (TNFα, IL-1β, and IL-6) were up-regulated in T2DM patients (P<0.05). The mRNA and protein levels of ChREBP were significantly elevated in the kidneys of diabetic mice. Moreover, glucose treatment promoted mRNA levels of TNF-α, IL-1β and IL-6 in mesangial cells. Glucose stimulation induced significant apoptosis of SV40 MES 13 cells. In addition, transfection with ChREBP siRNA significantly inhibited ChREBP expression. Consequently, the inflammatory responses and apoptosis were inhibited in SV40 MES 13 cells.

Conclusions: These results demonstrated that ChREBP could mediate the inflammatory response and apoptosis of mesangial cells, suggesting that ChREBP may be involved in the pathogenesis of DN.

Disclosure

Y. Chen: None. S. Zhao: None. Y. Wang: None.
Generation of a Novel Mouse Model to Study Pancreatic Beta-Cell Dedifferentiation
Authors: MAK TRACY C.S. , LATREILLE MATHIEU
Published: June 2018

Compromised β-cell identity triggered by metabolic stress has been revealed as a novel mechanism of insulin insufficiency in type 2 diabetes (T2D). Previous work from our group showed increased microRNA-7 (miR-7) expression in islets of mouse models of T2D and human islets exposed to an obesogenic environment. Murine β-cell-specific overexpression of miR-7 is sufficient to causes diabetes and is accompanied with decreased expression of β-cell identity markers, thus revealing miR-7 induction as a novel mechanism impairing β-cell identity. To address if insulin-producing cells can recover their function and identity in T2D, we engineered a novel mouse enabling us to temporally compromise the identity of β-cells through doxycycline-mediated miR-7 overexpression in vivo. We report that mutant mice exposed to doxycycline (Dox) displayed a severe diabetic phenotype characterized by hyperglycemia, glucose intolerance and reduced circulating insulin levels. Strikingly, four weeks after withdrawing Dox from the diet, we observed a complete normalization of glycemia, circulating insulin as well as the number of bihormonal cells in mutant mice. RNA seq analysis revealed that islets from miR-7-overexpressing mice exhibit a striking downregulation of β-cells identity markers and increased levels of α- and δ-cell specific genes. Interestingly, we measured upregulation of several genes involved in EMT, Inflammation and Stemness, pointing to a dedifferentiation of β-cells following induction of miR-7 expression. We provide novel evidence that miR-7 triggers an EMT process by repressing components of ATP-dependent chromatin remodelling complexes, altering nucleosome positioning at β-cell specific loci and ultimately causing dedifferentiation of β-cells. Together, our data reveal the mechanism underlying β-cell dedifferentiation by miR-7 and provide a proof of concept for the therapeutic efficacy of anti-miR-7 molecules in reversing β-cell dedifferentiation and improving β-cell function.

Disclosure

T.C.S. Mak: None. M. Latreille: None.