Cytochrome P-450 CYP2E1 knockout mice are protected against high-fat diet-induced obesity and insulin resistance.

Conventional (whole body) CYP2E1 knockout mice displayed protection against high-fat diet-induced weight gain, obesity, and hyperlipidemia with increased energy expenditure despite normal food intake and spontaneous locomotor activity. In addition, the CYP2E1 knockout mice displayed a marked improvement in glucose tolerance on both normal chow and high-fat diets. Euglycemic-hyperinsulinemic clamps demonstrated a marked protection against high-fat diet-induced insulin resistance in CYP2E1 knockout mice, with enhanced adipose tissue glucose uptake and insulin suppression of hepatic glucose output. In parallel, adipose tissue was protected against high-fat diet-induced proinflammatory cytokine production. Taken together, these data demonstrate that the CYP2E1 deletion protects mice against high-fat diet-induced insulin resistance with improved glucose homeostasis in vivo.

GLUT4 in murine bone growth: from uptake and translocation to proliferation and differentiation.

Skeletal growth, taking place in the cartilaginous growth plates of long bones, consumes high levels of glucose for both metabolic and anabolic purposes. We previously showed that Glut4 is present in growing bone and is decreased in diabetes. In the present study, we examined the hypothesis that in bone, GLUT4 gene expression and function are regulated via the IGF-I receptor (IGF-IR) and that Glut4 plays an important role in bone growth. Insulin and IGF-I actions on skeletal growth and glucose uptake were determined using mandibular condyle (MC) organ cultures and MC-derived primary cell cultures (MCDC). Chondrogenesis was determined by following proliferation and differentiation activities using immunohistochemical (IHC) analysis of proliferating cell nuclear antigen and type II collagen expression, respectively. Overall condylar growth was assessed morphometrically. GLUT4 mRNA and protein levels were determined using in situ hybridization and IHC, respectively. Glut4 translocation to the cell membrane was assessed using confocal microscopy analysis of GFP-Glut4 fusion-transfected cells and immunogold and electron microscopy on MC sections; glucose uptake was assayed by 2-deoxyglucose (2-DOG) uptake. Both IGF-I and insulin-stimulated glucose uptake in MCDC, with IGF-I being tenfold more potent than insulin. Blockage of IGF-IR abrogated both IGF-I- and insulin-induced chondrogenesis and glucose metabolism. IGF-I, but not insulin, induced Glut4 translocation to the plasma membrane. Additionally, insulin induced both GLUT4 and IGF-IR gene expression and improved condylar growth in insulin receptor knockout mice-derived MC. Moreover, silencing of GLUT4 gene in MCDC culture abolished both IGF-I-induced glucose uptake and chondrocytic proliferation and differentiation. In growing bone, the IGF-IR pathway stimulates Glut4 translocation and enhances glucose uptake. Moreover, intact Glut4 cellular levels and translocation machinery are essential for early skeletal growth.

GLUT4-overexpressing engineered muscle constructs as a therapeutic platform to normalize glycemia in diabetic mice.

Skeletal muscle insulin resistance is a main defect in type 2 diabetes (T2D), which is associated with impaired function and content of glucose transporter type 4 (GLUT4). GLUT4 overexpression in skeletal muscle tissue can improve glucose homeostasis. Therefore, we created an engineered muscle construct (EMC) composed of GLUT4-overexpressing (OEG4) cells. The ability of the engineered implants to reduce fasting glucose levels was tested in diet-induced obesity mice. Decrease and stabilization of basal glucose levels were apparent up to 4 months after implantation. Analysis of the retrieved constructs showed elevated expression of myokines and proteins related to metabolic processes. In addition, we validated the efficiency of OEG4-EMCs in insulin-resistant mice. Following high glucose load administration, mice showed improved glucose tolerance. Our data indicate that OEG4-EMC implant is an efficient mode for restoring insulin sensitivity and improving glucose homeostasis in diabetic mice. Such procedure is a potential innovative modality for T2D therapy.

The metabolic syndrome--from insulin resistance to obesity and diabetes.

In today's society with the escalating levels of obesity, diabetes, and cardiovascular disease, the metabolic syndrome is receiving considerable attention and is the subject of much controversy. Greater insight into the mechanism(s) behind the syndrome may improve our understanding of how to prevent and best manage this complex condition.

Transcriptional regulation of the GLUT4 gene: from PPAR-gamma and FOXO1 to FFA and inflammation.

The insulin-responsive glucose transporter 4 (GLUT4) has a major role in glucose uptake and metabolism in insulin target tissues (i.e. adipose and muscle cells). In these tissues, the peroxisome proliferator-activated receptor (PPAR) family of nuclear receptors and the winged-helix-forkhead box class O (FOXO) family of factors are two key families of transcription factors that regulate glucose homeostasis and insulin responsiveness. Type 2 diabetes mellitus and obesity are associated with impaired regulation of GLUT4 gene expression and elevated levels of free fatty acids and proinflammatory factors. Based on our studies of the interplay between PPAR-gamma, FOXO1 and free fatty acids, and inflammation in regulating GLUT4 transcription in sickness and in health, we suggest a novel paradigm to increase insulin sensitivity in bona fide insulin target cells.

Lessons learned from adapting a generic narrative diabetic-foot guideline to an institutional decision-support system.

Clinical guidelines usually need to be adapted to fit local practice before they can be actually used by clinicians. Reasons for adaptation include variations of institution setting such as type of practice and location, availability of resources, differences in patient populations, local policies, and practice patterns. When a guideline is implemented for clinical decision support and integrated with an institution's clinical information system, the data model of the local electronic medical record (EMR) and the data actually collected and stored in it also influence the guideline's adaptation. The purpose of this work is: (1) to characterize a tool-supported process for guideline encoding that addresses local adaptation and EMR integration, and (2) to identify the types of changes in guideline encoding during the local adaptation process.

Personalized epigenetic management of diabetes.

The novel genome-wide assays of epigenetic marks have resulted in a greater understanding of how genetics and the environment interact in the development and inheritance of diabetes. Chronic hyperglycemia induces epigenetic changes in multiple organs, contributing to diabetic complications. Specific epigenetic-modifying compounds have been developed to erase these modifications, possibly slowing down the onset of diabetes-related complications. The current review is an update of the previously published paper, describing the most recent advances in the epigenetics of diabetes.

The tumor suppressor p53 down-regulates glucose transporters GLUT1 and GLUT4 gene expression.

Tumorigenesis is associated with enhanced cellular glucose uptake and increased metabolism. Because the p53 tumor suppressor is mutated in a large number of cancers, we evaluated whether p53 regulates expression of the GLUT1 and GLUT4 glucose transporter genes. Transient cotransfection of osteosarcoma-derived SaOS-2 cells, rhabdomyosarcoma-derived RD cells, and C2C12 myotubes with GLUT1-P-Luc or GLUT4-P-Luc promoter-reporter constructs and wild-type p53 expression vectors dose dependently decreased both GLUT1 and GLUT4 promoter activity to approximately 50% of their basal levels. PG(13)-Luc activity, which was used as a positive control for functional p53 expression, was increased up to approximately 250-fold by coexpression of wild-type p53. The inhibitory effect of wild-type p53 was greatly reduced or abolished when cells were transfected with p53 with mutations in amino acids 143, 248, or 273. A region spanning -66/+163 bp of the GLUT4 promoter was both necessary and sufficient to mediate the inhibitory effects of p53. Furthermore, in vitro translated p53 protein was found to bind directly to two sequences in that region. p53-DNA binding was completely abolished by excess unlabeled probe but not by nonspecific DNA and was super-shifted by the addition of an anti-p53 antibody. Taken together, our data strongly suggest that wild-type p53 represses GLUT1 and GLUT4 gene transcription in a tissue-specific manner. Mutations within the DNA-binding domain of p53, which are usually associated with malignancy, were found to impair the repressive effect of p53 on transcriptional activity of the GLUT1 and GLUT4 gene promoters, thereby resulting in increased glucose metabolism and cell energy supply. This, in turn, would be predicted to facilitate tumor growth.

Challenges of implementing personalized (precision) medicine: a focus on diabetes.

The concept of personalized (precision) medicine (PM) emphasizes the scientific and technological innovations that enable the physician to tailor disease prediction, diagnosis and treatment to the individual patient, based on a personalized data-driven approach. The major challenge for the medical systems is to translate the molecular and genomic advances into clinical available means. Patients and healthcare providers, the pharmaceutical and diagnostic industries manifest a growing interest in PM. Multiple stakeholders need adaptation and re-engineering for successful clinical implementation of PM. Drawing primarily from the field of 'diabetes', this article will summarize the main challenges to implementation of PM into current medical practice and some of the approaches currently being implemented to overcome these challenges.

Personalized epigenetic management of diabetes.

Epigenetic regulation of gene expression allows the organism to respond/adapt to environmental conditions without changing the gene coding sequence. Epigenetic modifications have also been found to control gene expression in various diseases, including diabetes. Epigenetic changes induced by hyperglycemia in multiple target organs contribute to metabolic memory of diabetic complications. The long-lasting development of diabetic complications even after achieving glucose control has been partly attributed to epigenetic changes in target cells. Specific epigenetic drugs might rescue chromatin conformation associated to hyperglycemia possibly slowing down the onset of diabetes-related complications. The current review will describe the updated epigenetics in diabetes that can be used to personalize a more focused treatment.

Depressive symptoms prior to and following insulin initiation in patients with type 2 diabetes mellitus: Prevalence, risk factors and effect on physician resource utilisation.

AIMS: To study the frequency and intensity of depressive symptoms and associations with physician resource utilisation following insulin initiation in patients with type 2 diabetes mellitus. METHODS: SOLVE was a 24-week observational study. In this sub-analysis of data from Poland, depressive symptoms were evaluated using the Patient Health Questionnaire (PHQ)-9. RESULTS: PHQ-9 was completed by 942 of 1169 patients (80.6%) at baseline, and 751 (64.2%) at both baseline and final (24-week) visit. PHQ-9 scores indicated depressive symptoms in 45.6% (n=430) at baseline, and 27.2% (n=223) at final visit. Mean PHQ-9 change was -2.38 [95% CI -2.73, -2.02], p<0.001. Depressive symptoms at baseline (OR 6.32, p<0.001), microvascular disease (OR 2.45, p=0.016), number of physician contacts (OR 1.16, p=0.009), and change in HbA1c (OR 0.60, p=0.025) were independently associated with moderate/severe depressive symptoms at final visit. Patients with more severe depressive symptoms spent more time training to self-inject (p=0.0016), self-adjust (p=0.0023) and manage other aspects of insulin delivery (p<0.0001). Patients with persistent depressive symptoms had more telephone contacts and dose changes at final visit than those without (both p<0.05). CONCLUSIONS: Depressive symptoms are common with type 2 diabetes and associated with increased healthcare utilisation, reinforcing the need for holistic interdisciplinary management approaches.

PAX3/forkhead homolog in rhabdomyosarcoma oncoprotein activates glucose transporter 4 gene expression in vivo and in vitro.

Increased levels of glucose uptake and increased expression of the glucose transporter (GLUT) genes are characteristic features of tumors. In the muscle-derived tumor alveolar rhabdomyosarcoma (ARMS), a chromosomal translocation t(2:13) generates the PAX3/forkhead homolog in rhabdomyosarcoma (FKHR) oncoprotein. In muscle tissues, glucose transport is primarily mediated by GLUT4. However, the mechanisms that regulate GLUT4 gene expression in tumor tissues are largely unknown. Therefore, we evaluated the role of PAX3/FKHR in the regulation of GLUT4 gene expression in muscle tumorigenesis. GLUT4 mRNA and protein were detected in ARMS-derived human biopsies and in ARMS-derived RH30 myoblasts, which both express the PAX3/FKHR chimeric protein, but not in either C2C12 or embryonal rhabdomyosarcoma-derived myoblasts. GLUT4 was functionally active in RH30 cells, because insulin induced a 1.4-fold stimulation of basal 2-deoxyglucose uptake rates. Coexpression of PAX3/FKHR increased basal transcriptional activity from a GLUT4 promoter reporter (GLUT4-P) in C2C12, SaOS-2, and Chinese hamster ovary-K1 cells in a dose-dependent and tissue-specific manner. PAX3/FKHR mutants with deletions in either the homeodomain (DeltaHD) or the FKHR-derived activation domain (DeltaFKHR), or in which the PAX3-derived paired domain (PD) was point-mutated (PD-R56L), were unable to activate GLUT4-P. Progressive 5'-deletion analysis of GLUT4-P further identified a specific region of the promoter, -66/+163 bp, which retained about 65% of the full transactivation effect. EMSA studies established that the PAX3/FKHR protein directly and specifically binds to this region and to a shorter fragment, -4/+36 bp, that contains potential binding sites for HD and PD, but not to a -4/+36-bp fragment whose HD and PD sites have been mutated. Thus, the functional interaction of PAX3/FKHR with GLUT4-P appears to require all of the functional domains of PAX3/FKHR, as well as a -4/+36-bp region within the GLUT4 promoter. Taken together, the data suggest that the GLUT4 gene is a downstream target of PAX3/FKHR and that GLUT4 is aberrantly transactivated by this oncoprotein both in vivo and in vitro.

A single treatment with IL-4 via retrovirally transduced lymphocytes partially protects against diabetes in BioBreeding (BB) rats.

CONTEXT: Type 1 diabetes mellitus is a T cell mediated autoimmune disease with no known methods of prevention. The BioBreeding rat is used as an animal model for the study of human Type 1 diabetes. In spite of a severe lymphopenia, these animals develop spontaneous diabetes at the age of 10-12 weeks. OBJECTIVE: To examine whether anti-inflammatory gene therapy could be used to prevent autoimmune diabetes in the BioBreeding rat. DESIGN: A retroviral DNA vector, MSCVneo.IL-4, carrying the DNA sequence encoding the rat interleukin-4, was designed to transfer interleukin-4 to BioBreeding rats. Spleen cells of prediabetic animals were activated and transduced in vitro with replication-defective retroviruses expressing the MSCVneo.IL-4 vector. These lymphocytes were subsequently administered intraperitoneally to 3-4 week old prediabetic BioBreeding rats. Control animals were reconstituted with spleen cells transduced with MSCVneo vector. RESULTS: The neo gene marker was detectable by RT-PCR in rat spleen cells of up to 6 to 12 months after treatment. Fifty percent (6 out of 12) of the animals treated were protected from autoimmune disease development. CONCLUSION: Our results suggest that the BioBreeding rat can be used as a useful model to develop gene therapy regimens for diabetes. These studies provide further support for the hypothesis that interleukin-4 based gene therapy may have potential clinical value for preventing autoimmune diabetes in humans.

A model of the willingness to use telemedicine for routine and specialized care.

We examined factors associated with the willingness to use telemedicine for routine and specialized care within a theoretical framework. The conceptual model proposed that willingness to use telemedicine is associated directly with attitudes to telemedicine, attitudes to the patient-physician relationship, and to satisfaction with current health-care. In addition, technology anxiety and past behaviour were both assumed to affect willingness to use telemedicine indirectly. Telephone interviews were conducted with a national sample of 1204 Jewish, non-institutionalized adults in Israel. Structural equation modelling was used to examine the hypothesized relationships. Participants were more willing to use telemedicine for routine than for specialized care. Overall, willingness to use telemedicine was affected by attitudes to telemedicine, attitudes to the patient-physician relationship and by level of technology anxiety. Educational interventions aimed at encouraging the use of telemedicine should target potential users' attitudes, as well as feelings of uneasiness and anxiety regarding technology.

Introduction to personalized medicine in diabetes mellitus.

The world is facing an epidemic rise in diabetes mellitus (DM) incidence, which is challenging health funders, health systems, clinicians, and patients to understand and respond to a flood of research and knowledge. Evidence-based guidelines provide uniform management recommendations for "average" patients that rarely take into account individual variation in susceptibility to DM, to its complications, and responses to pharmacological and lifestyle interventions. Personalized medicine combines bioinformatics with genomic, proteomic, metabolomic, pharmacogenomic ("omics") and other new technologies to explore pathophysiology and to characterize more precisely an individual's risk for disease, as well as response to interventions. In this review we will introduce readers to personalized medicine as applied to DM, in particular the use of clinical, genetic, metabolic, and other markers of risk for DM and its chronic microvascular and macrovascular complications, as well as insights into variations in response to and tolerance of commonly used medications, dietary changes, and exercise. These advances in "omic" information and techniques also provide clues to potential pathophysiological mechanisms underlying DM and its complications.

Preventing type 2 diabetes mellitus: a call for personalized intervention.

In parallel with the rising prevalence of obesity worldwide, especially in younger people, there has been a dramatic increase in recent decades in the incidence and prevalence of metabolic consequences of obesity, in particular prediabetes and type 2 diabetes mellitus (DM2). Although approximately one-third of US adults now meet one or more diagnostic criteria for prediabetes, only a minority of those so identified as being at risk for DM2 actually progress to diabetes, and some may regress to normal status. Given the uncertain prognosis of prediabetes, it is not clear who is most likely to benefit from lifestyle change or medication interventions that are known to reduce DM2 risk. We review the many factors known to influence risk of developing DM2 and summarize treatment trials demonstrating the possibility of preventing DM2. Applying the concepts of personalized medicine and the potential of "big data" approaches to analysis of massive amounts of routinely gathered clinical and laboratory data from large populations, we call for the development of tools to more precisely estimate individual risk of DM2.

Effect of baseline glycosylated hemoglobin A1c on glycemic control and diabetes management following initiation of once-daily insulin detemir in real-life clinical practice.

OBJECTIVE: The SOLVE study investigated the initiation of basal insulin in patients with type 2 diabetes on oral antidiabetic (OAD) treatment and outcomes in patients with varying levels of glycemic control at baseline. METHODS: This was an observational cohort study conducted in 10 countries using insulin detemir. Data were collected at 3 clinic visits (baseline, 12-week interim, and 24-week final visit). RESULTS: A total of 13,526 (77.9%) patients were included in the glycosylated hemoglobin A1c (HbA1c) subset analysis. Patients were grouped according to pre-insulin HbA1c values as follows: HbA1c <7.6% (n = 2,797); HbA1c 7.6-9% (n = 5,366), and HbA1c >9% (n = 5,363). A total of 27 patients experienced serious adverse drug reactions (SADRs) and/or severe hypoglycemia (3, 10, and 11 patients with pre-insulin HbA1c <7.6%, 7.6-9.0%, and >9.0%, respectively). All patient subgroups realized improvements in HbA1c, with the pre-insulin HbA1c >9% subgroup having the largest HbA1c reduction (-2.4% versus -0.9% and -0.2% for HbA1c subgroups 7.6-9% and <7.6%, respectively). In the total cohort (n = 17,374), the incidence of severe hypoglycemia decreased from 4 events per 100 person years to <1 event per 100 person years by final visit; the incidence of minor hypoglycemia increased from 1.6 to 1.8 events per person year. CONCLUSIONS: In this study, insulin initiation was delayed until late in disease course, and overall concordance with internationally recognized guidelines was low. The initiation of once-daily insulin detemir was associated with substantial improvements in glycemic control and was not associated with an increase in severe hypoglycemia or weight gain.

Observational study of once-daily insulin detemir in people with type 2 diabetes aged 75 years or older: a sub-analysis of data from the Study of Once daily LeVEmir (SOLVE).

OBJECTIVES: Older patients are particularly vulnerable to hypoglycaemia. The aim of this study was to evaluate the response to initiation of once-daily insulin detemir in patients aged ≥75 years with type 2 diabetes mellitus (T2DM) treated with one or more oral antidiabetic drugs (OADs). METHODS: A sub-analysis was conducted using data from SOLVE (Study of Once daily LeVEmir), a 24-week observational study involving 3,219 investigators and 2,817 project sites from ten countries. Routine clinical practice was followed; there were no study-prescribed procedures. The total cohort comprised 17,374 participants, of whom 2,398 (14 %) were aged ≥75 years. The physicians collected information from patient recall, the patients' medical records and their self-monitored blood glucose diaries (if kept). RESULTS: Pre-insulin glycated haemoglobin (HbA(1c)) was similar between participants aged ≥75 years and those aged <75 years (HbA(1c) 8.8 ± 1.5 % vs. 8.9 ± 1.6 % [mean ± SD], respectively). After 24 weeks of treatment, similar reductions in HbA(1c) were observed in the two subgroups: 7.6 ± 1.1 % and 7.5 ± 1.2 % in participants aged ≥75 years and those aged <75 years, respectively. The incidence of severe hypoglycaemia (episodes per patient-year) decreased during the study in both age groups (from 0.057 to 0.007 in patients aged ≥75 years; from 0.042 to 0.005 in patients aged <75 years), while minor hypoglycaemia increased from 1.1 to 2.0 and from 1.7 to 1.8 episodes per patient-year in the older and younger age groups, respectively. Average weight reduction was similar in both groups: -0.5 kg (≥75 years) and -0.6 kg (<75 years). CONCLUSION: In both the older and younger age groups, the addition of once-daily insulin detemir to existing OAD regimens was effective and safe. In older patients, an improvement in HbA(1c) of 1.2 % was not associated with an increased risk of severe hypoglycaemia or weight gain.