Journal of Diabetes Research The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Antidiabetic and Renoprotective Effects of Cladophora glomerata Kützing Extract in Experimental Type 2 Diabetic Rats: A Potential Nutraceutical Product for Diabetic Nephropathy Thu, 26 Mar 2015 13:33:26 +0000 Cladophora glomerata extract (CGE) has been shown to exhibit antigastric ulcer, anti-inflammatory, analgesic, hypotensive, and antioxidant activities. The present study investigated antidiabetic and renoprotective effects of CGE in type 2 diabetes mellitus (T2DM) rats. The rats were induced by high-fat diet and streptozotocin and supplemented daily with 1 g/kg BW of CGE for 12 weeks. The renal transport function was assessed by the uptake of para-aminohippurate mediated organic anion transporters 1 (Oat1) and 3 (Oat3), using renal cortical slices. These two transporters were known to be upregulated by insulin and PKCζ while they were downregulated by PKCα activation. Compared to T2DM, CGE supplemented rats had significantly improved hyperglycaemia, hypertriglyceridemia, insulin resistance, and renal morphology. The baseline uptake of para-aminohippurate was not different among experimental groups and was correlated with Oat1 and 3 mRNA expressions. Nevertheless, while insulin-stimulated Oat1 and 3 functions in renal slices were blunted in T2DM rats, they were improved by CGE supplementation. The mechanism of CGE-restored insulin-stimulated Oat1 and 3 functions was clearly shown to be associated with upregulated PKCζ and downregulated PKCα expressions and activations. These findings indicate that CGE has antidiabetic effect and suggest it may prevent diabetic nephropathy through PKCs in a T2DM rat model. Chutima Srimaroeng, Atcharaporn Ontawong, Naruwan Saowakon, Pornpun Vivithanaporn, Anchalee Pongchaidecha, Doungporn Amornlerdpison, Sunhapas Soodvilai, and Varanuj Chatsudthipong Copyright © 2015 Chutima Srimaroeng et al. All rights reserved. Estrogen: An Emerging Regulator of Insulin Action and Mitochondrial Function Thu, 26 Mar 2015 12:35:06 +0000 Clinical trials and animal studies have revealed that loss of circulating estrogen induces rapid changes in whole body metabolism, fat distribution, and insulin action. The metabolic effects of estrogen are mediated primarily by its receptor, estrogen receptor-α; however, the detailed understanding of its mechanisms is incomplete. Recent investigations suggest that estrogen receptor-α elicits the metabolic effects of estrogen by genomic, nongenomic, and mitochondrial mechanisms that regulate insulin signaling, substrate oxidation, and energetics. This paper reviews clinical and experimental studies on the mechanisms of estrogen and the current state of knowledge regarding physiological and pathobiological influences of estrogen on metabolism. Anisha A. Gupte, Henry J. Pownall, and Dale J. Hamilton Copyright © 2015 Anisha A. Gupte et al. All rights reserved. Diabetic Foot Syndrome as a Possible Cardiovascular Marker in Diabetic Patients Thu, 26 Mar 2015 08:00:30 +0000 Diabetic foot ulcerations have been extensively reported as vascular complications of diabetes mellitus associated with a high degree of morbidity and mortality; in fact, some authors showed a higher prevalence of major, previous and new-onset, cardiovascular, and cerebrovascular events in diabetic patients with foot ulcers than in those without these complications. This is consistent with the fact that in diabetes there is a complex interplay of several variables with inflammatory metabolic disorders and their effect on the cardiovascular system that could explain previous reports of high morbidity and mortality rates in diabetic patients with amputations. Involvement of inflammatory markers such as IL-6 plasma levels and resistin in diabetic subjects confirmed the pathogenetic issue of the “adipovascular” axis that may contribute to cardiovascular risk in patients with type 2 diabetes. In patients with diabetic foot, this “adipovascular axis” expression in lower plasma levels of adiponectin and higher plasma levels of IL-6 could be linked to foot ulcers pathogenesis by microvascular and inflammatory mechanisms. The purpose of this review is to focus on the immune inflammatory features of DFS and its possible role as a marker of cardiovascular risk in diabetes patients. Antonino Tuttolomondo, Carlo Maida, and Antonio Pinto Copyright © 2015 Antonino Tuttolomondo et al. All rights reserved. Circulating Malondialdehyde-Modified LDL-Related Variables and Coronary Artery Stenosis in Asymptomatic Patients with Type 2 Diabetes Thu, 26 Mar 2015 07:30:40 +0000 Aims. To elucidate the levels of malondialdehyde-modified LDL (MDA-LDL)-related variables for predicting coronary artery stenosis (CAS) by coronary CT angiography (CCTA) in asymptomatic patients with type 2 diabetes (T2DM). Methods. Enrolled were 36 Japanese patients with T2DM who underwent CCTA and in whom MDA-LDL levels were measured. Definition of CAS was luminal narrowing of ≥50%. Trends through tertiles of each MDA-LDL-related variable were analyzed with a general linear model. The ability of each MDA-LDL-related variable to predict CAS was compared to areas under the curve (AUCs) in receiver operating characteristic curve (ROC) analysis. Results. Seventeen patients had CAS. Each MDA-LDL-related variable was an independent predictor of CAS ( for MDALDL, for MDA-LDL/LDL-C, for MDA-LDL/HDL-C, and for (MDA-LDL/LDL-C)/HDL-C). AUCs of MDA-LDL, MDA-LDL/LDL-C, MDA-LDL/HDL-C, and (MDA-LDL/LDL-C)/HDL-C were 0.675 (95% CI 0.496–0.854), 0.765 (0.602–0.927), 0.752 (0.592–0.913), and 0.799 (0.643–0.955), respectively, for predicting CAS. Trends throughout the tertiles showed significant associations between MDA-LDL/LDL-C, MDA-LDL/HDL-C, or (MDALDL/LDL-C)/HDL-C and CAS ( for MDA-LDL/LDL-C, for MDA-LDL/HDL-C, and for (MDA-LDL/LDL-C)/HDL-C). Conclusions. Data suggest that measurements of MDA-LDL/LDL-C, MDA-LDL/HDLC, and (MDA-LDL/LDL-C)/HDL-C are useful for predicting CAS. Kazuya Fujihara, Hiroaki Suzuki, Akira Sato, Satoru Kodama, Yoriko Heianza, Kazumi Saito, Hitoshi Iwasaki, Kazuto Kobayashi, Shigeru Yatoh, Akimitsu Takahashi, Naoya Yahagi, Hiroaki Yagyu, Hirohito Sone, and Hitoshi Shimano Copyright © 2015 Kazuya Fujihara et al. All rights reserved. Exposure to Common Food Additive Carrageenan Alone Leads to Fasting Hyperglycemia and in Combination with High Fat Diet Exacerbates Glucose Intolerance and Hyperlipidemia without Effect on Weight Wed, 25 Mar 2015 13:56:50 +0000 Aims. Major aims were to determine whether exposure to the commonly used food additive carrageenan could induce fasting hyperglycemia and could increase the effects of a high fat diet on glucose intolerance and dyslipidemia. Methods. C57BL/6J mice were exposed to either carrageenan, high fat diet, or the combination of high fat diet and carrageenan, or untreated, for one year. Effects on fasting blood glucose, glucose tolerance, lipid parameters, weight, glycogen stores, and inflammation were compared. Results. Exposure to carrageenan led to glucose intolerance by six days and produced elevated fasting blood glucose by 23 weeks. Effects of carrageenan on glucose tolerance were more severe than from high fat alone. Carrageenan in combination with high fat produced earlier onset of fasting hyperglycemia and higher glucose levels in glucose tolerance tests and exacerbated dyslipidemia. In contrast to high fat, carrageenan did not lead to weight gain. In hyperinsulinemic, euglycemic clamp studies, the carrageenan-exposed mice had higher early glucose levels and lower glucose infusion rate and longer interval to achieve the steady-state. Conclusions. Carrageenan in the Western diet may contribute to the development of diabetes and the effects of high fat consumption. Carrageenan may be useful as a nonobese model of diabetes in the mouse. Sumit Bhattacharyya, Leo Feferman, Terry Unterman, and Joanne K. Tobacman Copyright © 2015 Sumit Bhattacharyya et al. All rights reserved. Serum Potassium and Glucose Regulation in the ADDITION-Leicester Screening Study Wed, 25 Mar 2015 13:44:12 +0000 Introduction. Previous observational studies have shown conflicting results between plasma K+ concentrations and risk of type 2 diabetes. To help clarify the evidence we aimed to determine whether an association existed between serum K+ and glucose regulation within a UK multiethnic population. Methods. Participants were recruited as part of the ADDITION Leicester study, a population based screening study. Individuals from primary care between the age of 40 and 75 years if White European or 25 and 75 years if South Asian or Afro Caribbean were recruited. Tests for associations between baseline characteristics and K+ quartiles were conducted using linear regression models. Results. Data showed individuals in the lowest K+ quartile had significantly greater 2-hour glucose levels (0.53 mmol/L, 95% CI: 0.36 to 0.70, ) than those in the highest K+ quartile. This estimation did not change with adjustment for potential confounders. Conversely, participants in the lowest K+ quartile had a 0.14% lower HbA1c (95% CI −0.19 to −0.10: ) compared to those in the highest K+ quartile. Conclusion. This cross-sectional analysis demonstrated that lower K+ was associated with greater 2 hr glucose. The data supports the possibility that K+ may influence glucose regulation and further research is warranted. Patrice Carter, Danielle H. Bodicoat, Lauren M. Quinn, Francesco Zaccardi, David R. Webb, Kamlesh Khunti, and Melanie J. Davies Copyright © 2015 Patrice Carter et al. All rights reserved. Influence of Cardiorespiratory Fitness on PPARG mRNA Expression Using Monozygotic Twin Case Control Tue, 24 Mar 2015 11:38:59 +0000 The influence of cardiorespiratory fitness (VO2max) on anthropometric variables and PPARG mRNA expression was investigated. Monozygotic twin pairs aged 11–18 years were grouped into discordant (D) and concordant (C) high and low VO2max groups. VO2max was determined by progressive maximal exercise test on treadmill with gas exchange analysis. Body mass (BM), BMI, waist circumference (WC), triceps (TR), and subscapular (SB) skinfold thicknesses were measured. Twins from the discordant group had differences in VO2max values (D-high = versus D-low =  mL·kg−1·min−1, ), while no differences were found in the concordant group (C-high = versus C-low =  mL·kg−1·min−1, ). In discordant group, VO2max was negatively correlated with TR + SB (, ) and positively correlated with PPARG expression in leukocytes (, ). Moreover, PPARG expression was directly correlated with BM (, ) and height (, ). In concordant twins, VO2max was inversely correlated with BM (, ), BMI (, ), WC (, ), and TR + SB (, ). Twins D-high had 1.78-fold greater PPARG expression when compared with twins D-low (). In conclusion, the cardiorespiratory fitness may modulate PPARG expression in childhood and adolescence, independently of the genetic background. Marcos Roberto Queiroga, Ricardo Augusto Barbieri, Sandra Aires Ferreira, André Ducati Luchessi, Rosario Dominguez Crespo Hirata, Mario Hiroyuki Hirata, and Eduardo Kokubun Copyright © 2015 Marcos Roberto Queiroga et al. All rights reserved. Metformin Treatment in Type 2 Diabetes in Pregnancy: An Active Controlled, Parallel-Group, Randomized, Open Label Study in Patients with Type 2 Diabetes in Pregnancy Sun, 22 Mar 2015 14:13:04 +0000 Aims. To assess the effect of metformin and to compare it with insulin treatment in patients with type 2 diabetes in pregnancy in terms of perinatal outcome, maternal complications, additional insulin requirement, and treatment acceptability. Methods. In this randomized, open label study, 206 patients with type 2 diabetes in pregnancy who met the eligibility criteria were selected from the antenatal clinics. Insulin was added to metformin treatment when required, to maintain the target glycemic control. The patients were followed up till delivery. Maternal, and perinatal outcomes and pharmacotherapeutic characteristics were recorded on a proforma. Results. Maternal characteristics were comparable in metformin and insulin treated group. 84.9% patients in metformin group required add-on insulin therapy at mean gestational age of 26.58 ± 3.85 weeks. Less maternal weight gain and pregnancy induced hypertension were observed in metformin treated group. Small for date babies were more in metformin group . Neonatal hypoglycemia was significantly less and so was NICU stay of >24 hours in metformin group . Significant reduction in cost of treatment was found in metformin group. Conclusion. Metformin alone or with add-on insulin is an effective and cheap treatment option for patients with type 2 diabetes in pregnancy. This trial is registered with clinical trial registration number: Clinical NCT01855763. Jahan Ara Ainuddin, Nasim Karim, Sidra Zaheer, Syed Sanwer Ali, and Anjum Ara Hasan Copyright © 2015 Jahan Ara Ainuddin et al. All rights reserved. Changes in Plasma Levels of N-Arachidonoyl Ethanolamine and N-Palmitoylethanolamine following Bariatric Surgery in Morbidly Obese Females with Impaired Glucose Homeostasis Sun, 22 Mar 2015 11:06:18 +0000 Aim. We examined endocannabinoids (ECs) in relation to bariatric surgery and the association between plasma ECs and markers of insulin resistance. Methods. A study of 20 participants undergoing bariatric surgery. Fasting and 2-hour plasma glucose, lipids, insulin, and C-peptide were recorded preoperatively and 6 months postoperatively with plasma ECs (AEA, 2-AG) and endocannabinoid-related lipids (PEA, OEA). Results. Gender-specific analysis showed differences in AEA, OEA, and PEA preoperatively with reductions in AEA and PEA in females postoperatively. Preoperatively, AEA was correlated with 2-hour glucose (, ), HOMA-IR (, ), and HOMA %S (, ). OEA was correlated with weight (, ), waist circumference (, ), fasting insulin (, ), and HOMA-IR (, ). PEA was correlated with fasting insulin (, ). 2-AG had a negative correlation with fasting glucose (, ). Conclusion. Gender differences exist in circulating ECs in obese subjects. Females show changes in AEA and PEA after bariatric surgery. Specific correlations exist between different ECs and markers of obesity and insulin and glucose homeostasis. Akhila Mallipedhi, Sarah L. Prior, Gareth Dunseath, Richard M. Bracken, Jonathan Barry, Scott Caplin, Nia Eyre, James Morgan, John N. Baxter, Saoirse E. O’Sullivan, Sarir Sarmad, David A. Barrett, Stephen C. Bain, Steve D. Luzio, and Jeffrey W. Stephens Copyright © 2015 Akhila Mallipedhi et al. All rights reserved. Proteases and Protease Inhibitors of Urinary Extracellular Vesicles in Diabetic Nephropathy Thu, 19 Mar 2015 09:13:48 +0000 Diabetic nephropathy (DN) is one of the major complications of diabetes mellitus (DM), leads to chronic kidney disease (CKD), and, ultimately, is the main cause for end-stage kidney disease (ESKD). Beyond urinary albumin, no reliable biomarkers are available for accurate early diagnostics. Urinary extracellular vesicles (UEVs) have recently emerged as an interesting source of diagnostic and prognostic disease biomarkers. Here we used a protease and respective protease inhibitor array to profile urines of type 1 diabetes patients at different stages of kidney involvement. Urine samples were divided into groups based on the level of albuminuria and UEVs isolated by hydrostatic dialysis and screened for relative changes of 34 different proteases and 32 protease inhibitors, respectively. Interestingly, myeloblastin and its natural inhibitor elafin showed an increase in the normo- and microalbuminuric groups. Similarly, a characteristic pattern was observed in the array of protease inhibitors, with a marked increase of cystatin B, natural inhibitor of cathepsins L, H, and B as well as of neutrophil gelatinase-associated Lipocalin (NGAL) in the normoalbuminuric group. This study shows for the first time the distinctive alterations in comprehensive protease profiles of UEVs in diabetic nephropathy and uncovers intriguing mechanistic, prognostic, and diagnostic features of kidney damage in diabetes. Luca Musante, Dorota Tataruch, Dongfeng Gu, Xinyu Liu, Carol Forsblom, Per-Henrik Groop, and Harry Holthofer Copyright © 2015 Luca Musante et al. All rights reserved. Evaluating the Effect of Sarconesiopsis magellanica (Diptera: Calliphoridae) Larvae-Derived Haemolymph and Fat Body Extracts on Chronic Wounds in Diabetic Rabbits Wed, 18 Mar 2015 11:24:41 +0000 We evaluated extracts taken from S. magellanica third instar larvae fat body and haemolymph using a diabetic rabbit model and compared this to the effect obtained with the same substances taken from Lucilia sericata larvae. Alloxan (a toxic glucose analogue) was used to induce experimental diabetes in twelve rabbits. Dorsal wounds were made in each animal and they were infected with Staphylococcus aureus and Pseudomonas aeruginosa. They were then treated with haemolymph and lyophilized extracts taken from the selected blowflies’ larvae fat bodies. Each wound was then evaluated by using rating scales and histological analysis. More favourable scores were recorded on the PUSH and WBS scales for the wounds treated with fat body derived from the larvae of both species compared to that obtained with haemolymph; however, wounds treated with the substances taken from S. magellanica had better evolution. Histological analysis revealed that treatment led to tissue proliferation and more effective neovascularisation in less time with both species’ fat body extracts compared to treatment with just haemolymph. The results suggest the effectiveness of the substances evaluated and validate them in the animal model being used here as topical agents in treating chronic wounds. Jennifher Góngora, Andrea Díaz-Roa, Alejandro Ramírez-Hernández, Jesús A. Cortés-Vecino, María A. Gaona, Manuel A. Patarroyo, and Felio Bello Copyright © 2015 Jennifher Góngora et al. All rights reserved. NADPH Oxidase 4-Derived H2O2 Promotes Aberrant Retinal Neovascularization via Activation of VEGF Receptor 2 Pathway in Oxygen-Induced Retinopathy Wed, 18 Mar 2015 07:47:49 +0000 NADPH oxidase 4 (Nox4) is a major isoform of NADPH oxidase in retinal endothelial cells. Our previous study suggests that upregulation of Nox4 in retinal endothelial cells contributes to retinal vascular leakage in diabetes. In the current study, we investigated the role and mechanism of Nox4 in regulation of retinal neovascularization (NV), a hallmark of proliferative diabetic retinopathy (PDR), using a mouse model of oxygen-induced retinopathy (OIR). Our results confirmed that Nox4 was expressed predominantly in retinal vasculature of mouse retina. Retinal expression of Nox4 was markedly increased in OIR, in parallel with enhanced phosphorylation of ERK. In human retinal microvascular endothelial cells (HRECs), overexpression of Nox4 by adenovirus significantly increased extracellular H2O2 generation, resulting in intensified VEGFR2 activation and exacerbated angiogenesis upon VEGF stimulation. In contrast, silencing Nox4 expression or scavenging H2O2 by polyethylene glycol- (PEG-) conjugated catalase inhibited endothelial migration, tube formation, and VEGF-induced activation of VEGFR2 signaling. Importantly, knockdown of retinal Nox4 by adenovirus-delivered siRNA significantly reduced ERK activation and attenuated retinal NV formation in OIR. Taken together, our data indicate that Nox4 promotes retinal NV formation through H2O2/VEGFR2/ERK signaling pathway. Reducing retinal Nox4 expression may represent a promising therapeutic approach for neovascular retinal diseases such as PDR. Jingming Li, Joshua J. Wang, and Sarah X. Zhang Copyright © 2015 Jingming Li et al. All rights reserved. Towards Patient-Oriented Diabetes Care: Results from Two KORA Surveys in Southern Germany Tue, 17 Mar 2015 14:04:16 +0000 Objective. This study aims to examine the relationship of diabetes care processes and patient outcomes with an expanded set of indicators regarding patient-oriented care delivery, such as treatment satisfaction, the quality of patient-physician relationship, and a wider range of patient outcomes such as self-management, health behaviour, disease-related burden, and health-related quality of life (HRQL). Methods. The study population consisted of 486 participants with type 2 diabetes in two population-based follow-up surveys, conducted in 2003 to 2005 and 2006 to 2008 in Southern Germany. Data were self-reported and questionnaire-based, including the SF-12 for HRQL. Multiple regression models were used to identify associations between care processes and outcomes with adjustment for confounders. Results. Frequent medical examinations increased the likelihood of self-monitoring activities, such as foot care. A positive patient experienced relationship with their physician is associated with higher adherence to medical recommendations, such as medication intake, and the score of the SF-12 mental component. Participants with diabetes-related complications reported higher levels of medical examinations and multiprofessional care. Conclusions. Indicators of patient-oriented care should become an indispensable part of diabetes clinical practice guidelines with the aim of striving for more effective support of patients. Michaela Schunk, Renée Stark, Peter Reitmeir, Christa Meisinger, and Rolf Holle Copyright © 2015 Michaela Schunk et al. All rights reserved. Protective Effects of Scutellarin on Type II Diabetes Mellitus-Induced Testicular Damages Related to Reactive Oxygen Species/Bcl-2/Bax and Reactive Oxygen Species/Microcirculation/Staving Pathway in Diabetic Rat Thu, 12 Mar 2015 10:47:04 +0000 The goal of our study is to evaluate the effect of Scutellarin on type II diabetes-induced testicular disorder and show the mechanism of Scutellarin’s action. We used streptozotocin and high-fat diet to establish type II diabetic rat model. TUNEL and haematoxylin and eosin staining were used to evaluate the testicular apoptotic cells and morphologic changes. Immunohistochemical staining was used to measure the expression level of vascular endothelial growth factor and blood vessel density in testes. Oxidative stress in testes and epididymis was tested by fluorescence spectrophotometer and ELISA. The expression of Bcl-2/Bax and blood flow rate in testicular vessels were measured by western blot and Doppler. Our results for the first time showed that hyperglycemia induced apoptotic cells and morphologic impairments in testes of rats, while administration of Scutellarin can significantly inhibit these damages. This effect of Scutellarin is controlled by two apoptotic triggers: ROS/Bcl-2/Bax and ROS/microcirculation/starving pathway. Lingli Long, Jingnan Wang, Xiaofang Lu, Yuxia Xu, Shuhui Zheng, Canqiao Luo, and Yubin Li Copyright © 2015 Lingli Long et al. All rights reserved. NADPH Oxidase-Induced NALP3 Inflammasome Activation Is Driven by Thioredoxin-Interacting Protein Which Contributes to Podocyte Injury in Hyperglycemia Thu, 05 Mar 2015 06:53:56 +0000 Diabetic nephropathy (DN) is one of the major causes of end-stage renal disease, and previously we demonstrated that NALP3 inflammasome was involved in the pathogenesis of DN. Here we investigated the mechanisms of NALP3 inflammasome activation in podocyte injury during DN. We found that, besides the activation of NALP3 inflammasome and upregulated thioredoxin-interacting protein (TXNIP), the glomerular expression of , a subunit of NADPH oxidase, was enhanced in DN mice simultaneously. Inhibiting NADPH oxidase abrogated NALP3 inflammasome activation, and IL-1β production and eventually protected podocytes from high glucose- (HG-) induced injury. TXNIP, an inhibitor of thioredoxin, acts as a suppressor for antioxidant defense system. Our observation indicated that in HG-exposed podocytes genetic deletion of TXNIP by shRNA reversed overexpression and alleviated the injury of podocyte. Collectively, our findings proposed that HG-induced NADPH oxidase activation was driven by TXNIP which subsequently triggered NALP3 inflammasome activation in podocytes and ultimately led to podocyte injury, and blocking TXNIP/NADPH oxidase signaling may be a promising treatment for DN. Pan Gao, Fang-Fang He, Hui Tang, Chun-Tao Lei, Shan Chen, Xian-Fang Meng, Hua Su, and Chun Zhang Copyright © 2015 Pan Gao et al. All rights reserved. Regulation of Hyaluronan Synthesis in Vascular Diseases and Diabetes Thu, 05 Mar 2015 06:08:33 +0000 Cell microenvironment has a critical role determining cell fate and modulating cell responses to injuries. Hyaluronan (HA) is a ubiquitous extracellular matrix glycosaminoglycan that can be considered a signaling molecule. In fact, interacting with several cell surface receptors can deeply shape cell behavior. In vascular biology, HA triggers smooth muscle cells (SMCs) dedifferentiation which contributes to vessel wall thickening. Furthermore, HA is able to modulate inflammation by altering the adhesive properties of endothelial cells. In hyperglycemic conditions, HA accumulates in vessels and can contribute to the diabetic complications at micro- and macrovasculature. Due to the pivotal role in favoring atherogenesis and neointima formation after injuries, HA could be a new target for cardiovascular pathologies. This review will focus on the recent findings regarding the regulation of HA synthesis in human vascular SMCs. In particular, the effects of the intracellular HA substrates availability, adenosine monophosphate-activated protein kinase (AMPK), and protein O-GlcNAcylation on the main HA synthetic enzyme (i.e., HAS2) will be discussed. Paola Moretto, Evgenia Karousou, Manuela Viola, Ilaria Caon, Maria Luisa D’Angelo, Giancarlo De Luca, Alberto Passi, and Davide Vigetti Copyright © 2015 Paola Moretto et al. All rights reserved. Use of Drosophila as an Evaluation Method Reveals imp as a Candidate Gene for Type 2 Diabetes in Rat Locus Niddm22 Mon, 02 Mar 2015 09:59:15 +0000 Type 2 diabetes (T2D) is one of the most common human diseases. QTL analysis of the diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats has identified numerous hyperglycemic loci. However, molecular characterization and/or gene identification largely remains to be elucidated due mostly to the weak genetic variances contributed by each locus. Here we utilized Drosophila melanogaster as a secondary model organism for functional evaluation of the candidate gene. We demonstrate that the tissue specific knockdown of a homologue of igf2bp2 RNA binding protein leads to increased sugar levels similar to that found in the OLETF rat. In the mutant, the expression of two of the insulin-like peptides encoded in the fly genome, dilp2 and dilp3, were found to be downregulated. Consistent with previous reports of dilp mutants, the imp mutant flies exhibited an extension of life span; in contrast, starvation tolerance was reduced. These results further reinforce the possibility that imp is involved in sugar metabolism by modulating insulin expression. Kurenai Kawasaki, Sawaka Yamada, Koki Ogata, Yumiko Saito, Aiko Takahama, Takahisa Yamada, Kozo Matsumoto, and Hiroyuki Kose Copyright © 2015 Kurenai Kawasaki et al. All rights reserved. Pituitary Adenylate Cyclase-Activating Polypeptide Protects Glomerular Podocytes from Inflammatory Injuries Mon, 02 Mar 2015 06:40:31 +0000 Diabetic nephropathy (DN) is a leading cause of end-stage kidney disease; however, there are few treatment options. Inflammation plays a crucial role in the initiation and/or progression of DN. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide, which was originally isolated from the ovine hypothalamus and reportedly has diverse biological functions. It has been reported that PACAP has renoprotective effects in different models of kidney pathology. However, the specific cell types within the kidney that are protected by PACAP have not yet been reported. In this study, we localized VPAC1, one of the PACAP receptors, to glomerular podocytes, which also reportedly has crucial roles not only in glomerular physiology but also in pathology. PACAP was effective in the downregulation of proinflammatory cytokines, such as monocyte chemoattractant protein-1 (MCP-1) and interleukin-6, which had been induced by the activation of toll-like receptor (TLR) with lipopolysaccharide. PACAP also had downregulated the expression of MCP-1 through the protein kinase A signaling pathway; this led to the attenuation of the activation of extracellular signal-regulated kinase and nuclear factor-kappa B signaling. Our results suggested that PACAP could be a possible treatment option for DN through the use of anti-inflammation effects on glomerular podocytes. Kenichi Sakamoto, Kyoko Kuno, Minoru Takemoto, Peng He, Takahiro Ishikawa, Shunichiro Onishi, Ryoichi Ishibashi, Emiko Okabe, Mayumi Shoji, Akiko Hattori, Masaya Yamaga, Kazuki Kobayashi, Harukiyo Kawamura, Hirotake Tokuyama, Yoshiro Maezawa, and Koutaro Yokote Copyright © 2015 Kenichi Sakamoto et al. All rights reserved. Cholesterol-Induced Hepatic Inflammation Does Not Underlie the Predisposition to Insulin Resistance in Dyslipidemic Female LDL Receptor Knockout Mice Sat, 28 Feb 2015 08:03:13 +0000 Chronic inflammation is considered a causal risk factor predisposing to insulin resistance. However, evidence is accumulating that inflammation confined to the liver may not be causal to metabolic dysfunction. To investigate this, we assessed if hepatic inflammation explains the predisposition towards insulin resistance in low-density lipoprotein receptor knock-out (Ldlr−/−) mice. For this, wild type (WT) and Ldlr−/− mice were fed a chow diet, a high fat (HF) diet, or a high fat, high cholesterol (HFC) diet for 2 weeks. Plasma lipid levels were elevated in chow-fed Ldlr−/− mice compared to WT mice. Although short-term HF or HFC feeding did not result in body weight gain and adipose tissue inflammation, dyslipidemia was worsened in Ldlr−/− mice compared to WT mice. In addition, dyslipidemic HF-fed Ldlr−/− mice had a higher hepatic glucose production rate than HF-fed WT mice, while peripheral insulin resistance was unaffected. This suggests that HF-fed Ldlr−/− mice suffered from hepatic insulin resistance. While HFC-fed Ldlr−/− mice displayed the anticipated increased hepatic inflammation, this did neither exacerbate systemic nor hepatic insulin resistance. Therefore, our results show that hepatic insulin resistance is unrelated to cholesterol-induced hepatic inflammation in Ldlr−/− mice, indicating that hepatic inflammation may not contribute to metabolic dysfunction per se. Nanda Gruben, Anouk Funke, Niels J. Kloosterhuis, Marijke Schreurs, Fareeba Sheedfar, Rick Havinga, Sander M. Houten, Ronit Shiri-Sverdlov, Bart van de Sluis, Jan Albert Kuivenhoven, Debby P. Y. Koonen, and Marten H. Hofker Copyright © 2015 Nanda Gruben et al. All rights reserved. Alloxan-Induced Diabetes Causes Morphological and Ultrastructural Changes in Rat Liver that Resemble the Natural History of Chronic Fatty Liver Disease in Humans Thu, 19 Feb 2015 17:48:50 +0000 Purpose. This study evaluated the long-term effects of alloxan-induced diabetes in rat liver. Methods. Thirty nondiabetic control rats (NC) and 30 untreated diabetic (UD) rats were divided into three subgroups sacrificed after 6, 14, or 26 weeks. Clinical and laboratory parameters were assessed. Fresh liver weight and its relationship with body weight were obtained, and liver tissue was analyzed. Results. UD rats showed sustained hyperglycemia, high glycosylated hemoglobin, and low plasma insulin. High serum levels of AST and ALT were observed in UD rats after 2 weeks, but only ALT remained elevated throughout the experiment. Fresh liver weight was equal between NC and UD rats, but the fresh liver weight/body weight ratio was significantly higher in UD rats after 14 and 26 weeks. UD rats showed liver morphological changes characterized by hepatic sinusoidal enlargement and micro- and macrovesicular hepatocyte fatty degeneration with progressive liver structure loss, steatohepatitis, and periportal fibrosis. Ultrastructural changes of hepatocytes, such as a decrease in the number of intracytoplasmic organelles and degeneration of mitochondria, rough endoplasmic reticulum, and nuclei, were also observed. Conclusion. Alloxan-induced diabetes triggered liver morphological and ultrastructural changes that closely resembled human disease, ranging from steatosis to steatohepatitis and liver fibrosis. Amanda Natália Lucchesi, Lucas Langoni Cassettari, and César Tadeu Spadella Copyright © 2015 Amanda Natália Lucchesi et al. All rights reserved. The Role of Some Chemokines from the CXC Subfamily in a Mouse Model of Diabetic Neuropathy Thu, 19 Feb 2015 11:51:33 +0000 The mechanism involved in the development of diabetic neuropathy is complex. Currently, it is thought that chemokines play an important role in this process. The aim of this study was to determine how the level of some chemokines from the CXC subfamily varies in diabetic neuropathy and how the chemokines affect nociceptive transmission. A single intraperitoneal (i.p.) injection of streptozotocin (STZ; 200 mg/kg) resulted in an increased plasma glucose. The development of allodynia and hyperalgesia was measured at day 7 after STZ administration. Using Antibody Array techniques, the increases in CXCL1 (KC), CXCL5 (LIX), CXCL9 (MIG), and CXCL12 (SDF-1) protein levels were detected in STZ-injected mice. No changes in CXCL11 (I-TAC) or CXCL13 (BLC) protein levels were observed. The single intrathecal (i.t.) administration of CXCL1, CXCL5, CXCL9, and CXCL12 (each in doses of 10, 100, and 500 ng/5 μL) shows their pronociceptive properties as measured 1, 4, and 24 hours after injection using the tail-flick, von Frey, and cold plate tests. These findings indicate that the chemokines CXCL1, CXCL5, CXCL9, and CXCL12 are important in nociceptive transmission and may play a role in the development of diabetic neuropathy. Magdalena Zychowska, Ewelina Rojewska, Dominika Pilat, and Joanna Mika Copyright © 2015 Magdalena Zychowska et al. All rights reserved. Combination Therapy with Oleanolic Acid and Metformin as a Synergistic Treatment for Diabetes Thu, 19 Feb 2015 06:08:29 +0000 Aims and Background. Type 2 diabetes is a chronic disease that cannot be treated adequately using the known monotherapies, especially when the disease progresses to an advanced stage. In this study, we explore the possibility of treating the disease with a novel combination approach of oleanolic acid (OA), a glycogen phosphorylase (GP) inhibitor, and metformin. Methods. Db/db mice were randomly divided into four groups: a db/db control group, db/db mice treated with OA (250 mg/kg), db/db mice treated with metformin (100 mg/kg), and db/db mice treated with a combination of OA and metformin. All mice were treated for four weeks. The effects of the treatments on glucose homeostasis were measured using an OGTT, an assessment of insulin sensitivity and signaling in the liver, and the hepatic glucose production. Results. Combination therapy with OA and metformin significantly reduced the blood glucose and insulin levels and improved the liver pathology compared with that for the monotherapy in the db/db diabetic mouse model. We also found that the combination therapy significantly increased the mRNA expression of glycogen synthesis and decreased the GP, PGC-1α, PEPCK1, and G-6-Pase levels. In addition, the combination therapy with OA and metformin significantly increased the phosphorylation of AKT, PI3K, AMPK, and ACC and decreased the protein expression levels of G-6-Pase, PEPCK1, and TORC compared with those for either monotherapy. The combination therapy also reduced the phosphorylation of mTOR and CREB. Conclusions. Our results suggest that the combination therapy with OA and metformin has synergistic effects on the symptoms of db/db diabetic mice by improving glucose and insulin homeostasis. Xue Wang, Yupeng Chen, Daoud Abdelkader, Waseem Hassan, Hongbin Sun, and Jun Liu Copyright © 2015 Xue Wang et al. All rights reserved. Topically Applied Connective Tissue Growth Factor/CCN2 Improves Diabetic Preclinical Cutaneous Wound Healing: Potential Role for CTGF in Human Diabetic Foot Ulcer Healing Wed, 18 Feb 2015 08:14:34 +0000 Aims/Hypothesis. Topical application of CTGF/CCN2 to rodent diabetic and control wounds was examined. In parallel research, correlation of CTGF wound fluid levels with healing rate in human diabetic foot ulcers was undertaken. Methods. Full thickness cutaneous wounds in diabetic and nondiabetic control rats were treated topically with 1 μg rhCTGF or vehicle alone, on 2 consecutive days. Wound healing rate was observed on day 14 and wound sites were examined for breaking strength and granulation tissue. In the human study across 32 subjects, serial CTGF regulation was analyzed longitudinally in postdebridement diabetic wound fluid. Results. CTGF treated diabetic wounds had an accelerated closure rate compared with vehicle treated diabetic wounds. Healed skin withstood more strain before breaking in CTGF treated rat wounds. Granulation tissue from CTGF treatment in diabetic wounds showed collagen IV accumulation compared with nondiabetic animals. Wound α-smooth muscle actin was increased in CTGF treated diabetic wounds compared with untreated diabetic wounds, as was macrophage infiltration. Endogenous wound fluid CTGF protein rate of increase in human diabetic foot ulcers correlated positively with foot ulcer healing rate (; ). Conclusions/Interpretation. These data collectively increasingly substantiate a functional role for CTGF in human diabetic foot ulcers. F. R. Henshaw, P. Boughton, L. Lo, S. V. McLennan, and S. M. Twigg Copyright © 2015 F. R. Henshaw et al. All rights reserved. Women’s Views on Their Diagnosis and Management for Borderline Gestational Diabetes Mellitus Mon, 16 Feb 2015 13:15:33 +0000 Introduction. Little is known about women’s views relating to a diagnosis of borderline gestational diabetes mellitus (GDM) and the subsequent management. This study aimed to explore women’s experiences after being diagnosed with borderline GDM, their attitudes about treatment, and factors important to them for achieving any lifestyle changes. Methods. We conducted face-to-face, semistructured interviews with women diagnosed with borderline GDM. Results. A total of 22 women were interviewed. After a diagnosis of borderline GDM, 14 (64%) women reported not being concerned or worried. Management of borderline GDM was thought by 21 (95%) women to be very important or important. Eighteen (82%) women planned to improve their diet and/or exercise to manage their borderline GDM. The most frequently mentioned enabler for achieving intended lifestyle change was being more motivated to improve the health of their baby and/or themselves (15 women). The most frequent barrier was tiredness and/or being physically unwell (11 women). Conclusions. A diagnosis of borderline GDM caused some concern to one-third of women interviewed. The majority of women believed managing their borderline GDM was important and they planned to improve their lifestyle. Women’s own and their babies’ future health were powerful motivators for lifestyle change. Shanshan Han, Philippa F. Middleton, Tanya K. Bubner, and Caroline A. Crowther Copyright © 2015 Shanshan Han et al. All rights reserved. Ameliorative Effect of Allopurinol on Vascular Complications of Insulin Resistance Sun, 15 Feb 2015 14:38:31 +0000 The aim of the current study was to evaluate the possible protective effect of allopurinol (Allo) on experimentally induced insulin resistance (IR) and vascular complications. Rats were divided into four groups: control, IR, allopurinol-treated IR (IR-Allo), and allopurinol-treated control (Allo). IR was induced by adding fructose and high fat, high salt diet for 12 weeks. The results showed that Allo has alleviated the increased level of TNF-α and the systolic, diastolic, mean, and notch pressure observed in IR with no change in pulse pressure. In addition, Allo decreased the heart rate in the treated group compared to IR rats. On the other hand, it has no effect on increased levels of insulin, glucose, fructosamine, or body weight gain compared to IR group, while it increased significantly the insulin level and body weight without hyperglycemia in the control group. Moreover, Allo treatment ameliorated increased level of 4HNE, Ang II, and Ang R1. In conclusion, the results of the current study show that Allo has a protective effect on vascular complications of IR which may be attributed to the effect of Allo on decreasing the TNF-α, 4HNE, Ang II, and Ang R1 as well as increasing the level of insulin secretion. Hany M. El-Bassossy, Ahmed A. Elberry, Ahmad Azhar, Salah A. Ghareib, and Abdulrahman M. Alahdal Copyright © 2015 Hany M. El-Bassossy et al. All rights reserved. Polymorphisms of GLP-1 Receptor Gene and Response to GLP-1 Analogue in Patients with Poorly Controlled Type 2 Diabetes Sun, 15 Feb 2015 13:13:38 +0000 Aim. The relationship between genetic polymorphisms of the glucagon-like peptide-1 (GLP-1) receptor (GLP1R) gene and unresponsiveness to GLP-1 analogue treatment in patients with poorly controlled type 2 diabetes mellitus (DM) is unclear. Methods. Thirty-six patients with poorly controlled type 2 DM were enrolled and they received six days of continuous subcutaneous insulin infusion for this study. After the normalization of blood glucose in the first 3 days, the patients then received a combination therapy with injections of the GLP-1 analogue, exenatide, for another 3 days. All 13 exons and intron-exon boundaries of the GLP1R gene were amplified to investigate the association. Results. The short tandem repeat at 8GA/7GA (rs5875654) had complete linkage disequilibrium (LD, with ) with single nucleotide polymorphism (SNP) rs761386. Quantitative trait loci analysis of GLP1R gene variation with clinical response of GLP1 analogue showed the missense rs3765467 and rs761386 significantly associated with changes in the standard deviation of plasma glucose () ( and 0.019, resp.). The reported values became insignificant after multiple testing adjustments. Conclusion. The variable response to the GLP-1 analogue was not statistically correlated with polymorphisms of the GLP1R gene in patients with poorly controlled type 2 DM. Chia-Hung Lin, Yun-Shien Lee, Yu-Yao Huang, Sheng-Hwu Hsieh, Zih-Syuan Chen, and Chi-Neu Tsai Copyright © 2015 Chia-Hung Lin et al. All rights reserved. Animal Models of Diabetic Macrovascular Complications: Key Players in the Development of New Therapeutic Approaches Sun, 15 Feb 2015 10:55:09 +0000 Diabetes mellitus is a lifelong, incapacitating metabolic disease associated with chronic macrovascular complications (coronary heart disease, stroke, and peripheral vascular disease) and microvascular disorders leading to damage of the kidneys (nephropathy) and eyes (retinopathy). Based on the current trends, the rising prevalence of diabetes worldwide will lead to increased cardiovascular morbidity and mortality. Therefore, novel means to prevent and treat these complications are needed. Under the auspices of the IMI (Innovative Medicines Initiative), the SUMMIT (SUrrogate markers for Micro- and Macrovascular hard end points for Innovative diabetes Tools) consortium is working on the development of novel animal models that better replicate vascular complications of diabetes and on the characterization of the available models. In the past years, with the high level of genomic information available and more advanced molecular tools, a very large number of models has been created. Selecting the right model for a specific study is not a trivial task and will have an impact on the study results and their interpretation. This review gathers information on the available experimental animal models of diabetic macrovascular complications and evaluates their pros and cons for research purposes as well as for drug development. Suvi E. Heinonen, Guillem Genové, Eva Bengtsson, Thomas Hübschle, Lina Åkesson, Katrin Hiss, Agnes Benardeau, Seppo Ylä-Herttuala, Ann-Cathrine Jönsson-Rylander, and Maria F. Gomez Copyright © 2015 Suvi E. Heinonen et al. All rights reserved. Inflammatory Cytokines in Diabetic Nephropathy Sun, 15 Feb 2015 08:59:21 +0000 Probably, the most paradigmatic example of diabetic complication is diabetic nephropathy, which is the largest single cause of end-stage renal disease and a medical catastrophe of worldwide dimensions. Metabolic and hemodynamic alterations have been considered as the classical factors involved in the development of renal injury in patients with diabetes mellitus. However, the exact pathogenic mechanisms and the molecular events of diabetic nephropathy remain incompletely understood. Nowadays, there are convincing data that relate the diabetes inflammatory component with the development of renal disease. This review is focused on the inflammatory processes that develop diabetic nephropathy and on the new therapeutic approaches with anti-inflammatory effects for the treatment of chronic kidney disease in the setting of diabetic nephropathy. Javier Donate-Correa, Ernesto Martín-Núñez, Mercedes Muros-de-Fuentes, Carmen Mora-Fernández, and Juan F. Navarro-González Copyright © 2015 Javier Donate-Correa et al. All rights reserved. Synergistic Activations of REG Iα and REG Iβ Promoters by IL-6 and Glucocorticoids through JAK/STAT Pathway in Human Pancreatic β Cells Thu, 12 Feb 2015 13:32:22 +0000 Reg (Regenerating gene) gene was originally isolated from rat regenerating islets and its encoding protein was revealed as an autocrine/paracrine growth factor for β cells. Rat Reg gene is activated in inflammatory conditions for β cell regeneration. In human, although five functional REG family genes (REG Iα, REG Iβ, REG III, HIP/PAP, and REG IV) were isolated, their expressions in β cells under inflammatory conditions remained unclear. In this study, we found that combined addition of IL-6 and dexamethasone (Dx) induced REG Iα and REG Iβ expression in human 1.1B4 β cells. Promoter assay revealed that a signal transducer and activator of transcription- (STAT-) binding site in each promoter of REG Iα (TGCCGGGAA) and REG Iβ (TGCCAGGAA) was essential for the IL-6+Dx-induced promoter activation. A Janus kinase 2 (JAK2) inhibitor significantly inhibited the IL-6+Dx-induced REG Iα and REG Iβ transcription. Electrophoretic mobility shift assay and chromatin immunoprecipitation revealed that IL-6+Dx stimulation increased STAT3 binding to the REG Iα promoter. Furthermore, small interfering RNA-mediated targeting of STAT3 blocked the IL-6+Dx-induced expression of REG Iα and REG Iβ. These results indicate that the expression of REG Iα and REG Iβ should be upregulated in human β cells under inflammatory conditions through the JAK/STAT pathway. Akiyo Yamauchi, Asako Itaya-Hironaka, Sumiyo Sakuramoto-Tsuchida, Maiko Takeda, Kiyomi Yoshimoto, Tomoko Miyaoka, Takanori Fujimura, Hiroki Tsujinaka, Chikatsugu Tsuchida, Hiroyo Ota, and Shin Takasawa Copyright © 2015 Akiyo Yamauchi et al. All rights reserved. Characterisation of Pain Responses in the High Fat Diet/Streptozotocin Model of Diabetes and the Analgesic Effects of Antidiabetic Treatments Tue, 10 Feb 2015 05:59:46 +0000 Chronic pain is a common complication of diabetes. The aim of the present study was to characterise pain behaviour in a high fat diet/streptozotocin (HFD/STZ) model of diabetes in the rat, investigate spinal mechanisms, and determine the effects of antidiabetic interventions. Three-week consumption of a high fat diet followed by single injection of STZ (45 mgkg−1) produced sustained changes in plasma insulin and glucose until day 120. Hindpaw mechanical withdrawal thresholds were significantly lowered in the model, but mechanically evoked responses of spinal neurones were unaltered, compared to HFD/vehicle rats. HFD/STZ rats had significantly lower numbers of spinal Iba-1 positive cells (morphologically identified as activated microglia) and spinal GFAP immunofluorescence (a marker of astrogliosis) in the spinal cord at day 50, compared to time-matched controls. The PPARγ ligand pioglitazone (10 mgkg−1) did not alter HFD/STZ induced metabolic changes or hindpaw withdrawal thresholds of HFD/STZ rats. Daily linagliptin (3 mgkg−1) and metformin (200 mgkg−1) from day 4 after model induction did not alter plasma glucose or insulin in HFD/STZ rats but significantly prevented changes in the mechanical withdrawal thresholds. The demonstration that currently prescribed antidiabetic drugs prevent aberrant pain behaviour supports the use of this model to investigate pain mechanisms associated with diabetes. Frederika Maria Byrne, Sharon Cheetham, Steven Vickers, and Victoria Chapman Copyright © 2015 Frederika Maria Byrne et al. All rights reserved.