Yes / Introduction Type 2 diabetes mellitus (T2DM) promotes adverse myocardial remodeling and increased risk of heart failure; effects that can occur independently of hypertension or coronary artery disease. As cardiac fibroblasts (CFs) are key effectors of myocardial remodeling, we investigated whether inherent phenotypic differences exist in CF derived from T2DM donors compared with cells from nondiabetic (ND) donors. Methods Cell morphology (cell area), proliferation (cell counting over 7-day period), insulin signaling [phospho-Akt and phospho-extracellular signal-regulated kinase (ERK) Western blotting], and mRNA expression of key remodeling genes [real-time reverse transcription-polymerase chain reaction (RT-PCR)] were compared in CF cultured from atrial tissue from 14 ND and 12 T2DM donors undergoing elective coronary artery bypass surgery. Results The major finding was that Type I collagen (COL1A1) mRNA levels were significantly elevated by twofold in cells derived from T2DM donors compared with those from ND donors; changes reflected at the protein level. T2DM cells had similar proliferation rates but a greater variation in cell size and a trend towards increased cell area compared with ND cells. Insulin-induced Akt and ERK phosphorylation were similar in the two cohorts of cells. Conclusion CF from T2DM individuals possess an inherent profibrotic phenotype that may help to explain the augmented cardiac fibrosis observed in diabetic patients.

Yes / Type 2 diabetes mellitus (T2DM) is increasing worldwide, and it is associated with increased risk of coronary artery disease (CAD). For T2DM patients, the main surgical intervention for CAD is autologous saphenous vein grafting. However, T2DM patients have increased risk of saphenous vein graft failure (SVGF). While the mechanisms underlying increased risk of vascular disease in T2DM are not fully understood, hyperglycaemia, insulin resistance, and hyperinsulinaemia have been shown to contribute to microvascular damage, whereas clinical trials have reported limited effects of intensive glycaemic control in the management of macrovascular complications. This suggests that factors other than glucose exposure may be responsible for the macrovascular complications observed in T2DM. SVGF is characterised by neointimal hyperplasia (NIH) arising from endothelial cell (EC) dysfunction and uncontrolled migration and proliferation of vascular smooth muscle cells (SMCs). This is driven in part by proinflammatory cytokines released from the activated ECs and SMCs, particularly interleukin 6 (IL-6). IL-6 stimulation of the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT) pathway is a key mechanism through which EC inflammation, SMC migration, and proliferation are controlled and whose activation might therefore be enhanced in patients with T2DM. In this review, we investigate how proinflammatory cytokines, particularly IL-6, contribute to vascular damage resulting in SVGF and how suppression of proinflammatory cytokine responses via targeting the JAK/STAT pathway could be exploited as a potential therapeutic strategy. These include the targeting of suppressor of cytokine signalling (SOCS3), which appears to play a key role in suppressing unwanted vascular inflammation, SMC migration, and proliferation. / FTM is supported by a University of Botswana PhD scholarship.

No / The global prevalence Type 2 diabetes mellitus (T2DM) is escalating at a rapid rate. Patients with T2DM suffer from a multitude of complications and one of these is impaired wound healing. This can lead to the development of non-healing sores or foot ulcers and ultimately to amputation. In healthy individuals, wound healing follows a controlled and overlapping sequence of events encompassing inflammation, proliferation, and remodelling. In T2DM, one or more of these steps becomes dysfunctional. Current models to study impaired wound healing in T2DM include in vitro scratch wound assays, skin equivalents, or animal models to examine molecular mechanisms underpinning wound healing and/or potential therapeutic options. However, these do not fully recapitulate the complex wound healing process in T2DM patients, and ex vivo human skin tests are problematic due to the ethics of taking punch biopsies from patients where it is known they will heal poorly. Here, a technique is described whereby expression profiles of the specific cells involved in the (dys)functional wound healing response in T2DM patients can be examined using surplus tissue discarded following amputation or elective cosmetic surgery. In this protocol samples of donated skin are collected, wounded, cultured ex vivo in the air liquid interface, fixed at different time points and sectioned. Specific cell types involved in wound healing (e.g., epidermal keratinocytes, dermal fibroblasts (papillary and reticular), the vasculature) are isolated using laser capture microdissection and differences in gene expression analyzed by sequencing or microarray, with genes of interest further validated by qPCR. This protocol can be used to identify inherent differences in gene expression between both poorly healing and intact skin, in patients with or without diabetes, using tissue ordinarily discarded following surgery. It will yield greater understanding of the molecular mechanisms contributing to T2DM chronic wounds and lower limb loss. / European Commission 7th Framework Programme for Research and Technical Development - Marie Curie Innovative Training Networks (ITN), Grant agreement no 607886. Aveda, Hair Innovation & Technology, USA

Hyperglycaemia stimulates a variety of biochemical abnormalities. The area of particular interest in this study is the influence of non-enzymatic glycation of proteins on iron homeostasis, and particularly on non-transferrin-bound iron (NTBI) and its possible relation to atherogenesis in both Type 2 diabetic and obese non diabetic subjects. The link between non-enzymatic glycation of proteins and iron homeostasis, and development of macrovascular disease may be mechanistically different in Type 2 diabetic and obese non diabetic subjects due to a difference in the protein glycation pattern. Because the following in vivo study required storage of samples for up to two years to complete the processing of all the samples, a storage study was carried out using different anticoagulants and addition of reduced glutathione (GSH) to samples to study the effects of storage, thawing and freezing of the samples on the level of malondialdehyde (MDA), a biomarker of lipid peroxidation. This storage study showed that EDTA attenuated the action of lipid oxidation compared with lithium heparin (LiH). A combination of GSH with either EDTA or LiH added more protection from lipid peroxidation in the first week of storage, but due to the thawing and freezing of the sample the action of GSH diminished through its autooxidation, meaning that addition of GSH to samples in the following in vivo study would be useless. An in vivo study was carried out on iron-related parameters in three subject groups: control (non-diabetic, non-obese), Type 2 diabetic and obese non diabetic. Glycated haemoglobin (HbA1C) was strongly correlated with NTBI in the diabetic group. Also the level of NTBI was significantly increased in Type 2 diabetic subjects compared with other groups while the level of total iron was significantly decreased. The study showed a strong positive correlation between NTBI and a biomarker of endothelium dysfunction (E-selectin) in all groups studied. Although it is not possible from the current data to know if there is a causal relationship between these two parameters, it remains a possibility that iron released from its binding sites could initiate oxidative damage to the endothelial cells and begin the process of atherogenesis. Positive correlation at the 90% confidence level between NTBI and a biomarker of inflammation, high sensitivity C-reactive protein, is another indicator in this study of a link between increases in NTBI, inflammation, endothelium dysfunction and atherosclerosis. This study also showed for first time that NTBI is present in higher levels in the plasma of obese subjects compared to controls despite the obese subjects having significantly lower total iron. An in vitro study found that glycation of transferrin half saturated with iron increased with increasing glucose concentration, leading to decreased capacity of transferrin to hold iron and increased release of free iron. Also co-incubation of transferrin half saturated with iron with low density lipoprotein (LDL) and glucose showed oxidation of LDL (measured as MDA). This may be explained by the effect of glycation, leading to release of free iron, which catalyses oxidation of LDL. In addition, glycation of LDL may enhance the oxidation of LDL catalysed by iron. Both studies indicate that the glycation of proteins has a major impact on iron homeostasis leading to release of non-enzymatic glycation and contributing to one of the most common complications of Type 2 diabetes, atherosclerosis.

Type 2 Diabetes (T2D) disproportionally affects ethnic minorities in the United States. The development of T2D involves complex interaction between environmental factors and genetic predisposition. The genetic associations of six single nucleotide polymorphisms (SNPs) in TCF7L2 gene with the risk of T2D were evaluated in three high risk minority populations: Cuban Americans, Haitian Americans, and African Americans. For Cuban Americans, four SNPs (rs7901695, rs4506565, rs7903146 and rs11225537) were significantly associated with the risk of T2D after multivariable adjustment (p=0.018, p=0.016, p=0.014, and p=0.0008, respectively). Among controls, risk allele carriers of SNPs rs7901695, rs4506565 and rs7903146 had significantly higher fasting glucose level, compared to non-risk allele carriers. Additionally, a significant interaction between dietary fiber intake and SNP rs7903146 for the risk of T2D (p= 0.044) was found in Cuban Americans. Similarly, for SNP rs7901695, significant interaction was also found for fiber intake (p=0.014) as well as glycemic load (p=0.040). Subgroup analysis revealed that significant associations were only found within higher intake groups of dietary factors for both SNPs. For Haitian Americans, SNPs rs11196205 (p=0.059) and rs7895340 (p=0.069) showed marginal significance for the risk of T2D. After stratification by gender, SNPs with marginal significance from the gender-combined analysis became statistically significant with the same trend for the risk of T2D when analysis were done in males: rs11196205 (p=0.034) and rs7895340 (p=0.024). For African Americans, SNP rs7903146 (p=0.065) showed a marginal significance with the risk of T2D in gender-combined analysis and a statistical significance (p=0.013) in males. Two additional SNPs rs7901695 and rs4506565 were found to be significantly associated with the risk of T2D in males. Risk allele carriers of these two SNPs had significantly higher mean level of the fasting glucose level, compared to non-risk allele carriers in controls. T2D related quantitative trait analysis also demonstrated that in controls, compared to non-minor allele carriers of SNP rs12255372, minor allele carriers had significantly higher means of BMI, diastolic blood pressure, numbers of components of Metabolic Syndrome, significantly lower mean values of HDL-cholesterol and adiponectin. Taken together, our studies demonstrated ethno-specific genetic associations between TCF7L2 gene and the risk of T2D and related phenotypes.

No description available.

Type 2 diabetes (T2D) is a health problem throughout the world. In 2010, there were nearly 230 million individuals with diabetes worldwide and it is estimated that in the economically advanced countries the cases will increase about 50% in the next twenty years. Insulin resistance is one of major features in T2D, which is also a risk factor for metabolic and cardiovascular complications. Epidemiological and animal studies have shown that the consumption of vegetables and fruits can delay or prevent the development of the disease, although the underlying mechanisms of these effects are still unclear. Brassica species such as broccoli (Brassica oleracea var. italica) and nasturtium (Tropaeolum majus) possess high content of bioactive phytochemicals, e.g. nitrogen sulfur compounds (glucosinolates and isothiocyanates) and polyphenols largely associated with the prevention of cancer. Isothiocyanates (ITCs) display their anti-carcinogenic potential by inducing detoxicating phase II enzymes and increasing glutathione (GSH) levels in tissues. In T2D diabetes an increase in gluconeogenesis and triglyceride synthesis, and a reduction in fatty acid oxidation accompanied by the presence of reactive oxygen species (ROS) are observed; altogether is the result of an inappropriate response to insulin. Forkhead box O (FOXO) transcription factors play a crucial role in the regulation of insulin effects on gene expression and metabolism, and alterations in FOXO function could contribute to metabolic disorders in diabetes. In this study using stably transfected human osteosarcoma cells (U-2 OS) with constitutive expression of FOXO1 protein labeled with GFP (green fluorescent protein) and human hepatoma cells HepG2 cell cultures, the ability of benzylisothiocyanate (BITC) deriving from benzylglucosinolate, extracted from nasturtium to modulate, i) the insulin-signaling pathway, ii) the intracellular localization of FOXO1 and iii) the expression of proteins involved in glucose metabolism, ROS detoxification, cell cycle arrest and DNA repair was evaluated. BITC promoted oxidative stress and in response to that induced FOXO1 translocation from cytoplasm into the nucleus antagonizing the insulin effect. BITC stimulus was able to down-regulate gluconeogenic enzymes, which can be considered as an anti-diabetic effect; to promote antioxidant resistance expressed by the up-regulation in manganese superoxide dismutase (MnSOD) and detoxification enzymes; to modulate autophagy by induction of BECLIN1 and down-regulation of the mammalian target of rapamycin complex 1 (mTORC1) pathway; and to promote cell cycle arrest and DNA damage repair by up-regulation of the cyclin-dependent kinase inhibitor (p21CIP) and Growth Arrest / DNA Damage Repair (GADD45). Except for the nuclear factor (erythroid derived)-like2 (NRF2) and its influence in the detoxification enzymes gene expression, all the observed effects were independent from FOXO1, protein kinase B (AKT/PKB) and NAD-dependent deacetylase sirtuin-1 (SIRT1). The current study provides evidence that besides of the anticarcinogenic potential, isothiocyanates might have a role in T2D prevention. BITC stimulus mimics the fasting state, in which insulin signaling is not triggered and FOXO proteins remain in the nucleus modulating gene expression of their target genes, with the advantage of a down-regulation of gluconeogenesis instead of its increase. These effects suggest that BITC might be considered as a promising substance in the prevention or treatment of T2D, therefore the factors behind of its modulatory effects need further investigation. / Diabetes mellitus Typ 2 stellt auf der ganzen Welt ein Gesundheitsproblem dar. Im Jahr 2010 waren annähernd 230 Millionen Personen weltweit an Diabetes erkrankt und innerhalb der nächsten 20 Jahre wird in industrialisierten Ländern eine Steigerung der Fälle um 50% erwartet. Eines der Hauptmerkmale des Typ 2 Diabetes ist die Insulinresistenz, die auch als Risikofaktor für metabolische und kardio-vaskuläre Komplikationen gilt. Epidemiologische Studien und Tierversuche haben ergeben, dass durch Verzehr von Gemüse und Obst eine Prävention oder Verzögerung der Entwicklung dieser Krankheit erreicht werden kann, jedoch sind die zugrunde liegenden Mechanismen dieser Effekte noch nicht aufgeklärt. Brassica Spezies wie Broccoli (Brassica oleracea var. italica) und Nasturtium (Tropaeolum majus) enthalten einen hohen Anteil an bioaktiven Pflanzen-inhaltsstoffen, wie z. B. stickstoff- und schwefelhaltige Verbindungen (Glukosinolate und Isothiocyanate) und Polyphenole, die bisher hauptsächlich mit der Prävention von Krebs assoziiert wurden. Isothiocyanate (ITCs) erreichen ihr antikanzerogenes Potential durch die Induktion von entgiftenden Phase II Enzymen und eine Anhebung der Glutathion (GSH)-Spiegel im Gewebe. Diabetes Typ2 geht einher mit einem Anstieg der Glukoneogenese und Triglycerid-Synthese, sowie einer Reduktion der Fettsäure-Oxidation in Verbindung mit erhöhten Spiegeln an reaktiven Sauerstoffspezies (ROS) insgesamt als Resultat einer unangemessenen Insulinantwort. Forkhead box O (FOXO) Transkriptionsfaktoren spielen eine wesentliche Rolle in der Regulation der Insulineffekte in Bezug auf die vermittelte Genexpression und den Metabolismus, wobei Veränderungen in der Funktion von FOXO zu metabolischen Entgleisungen im Diabetes beitragen können. In dieser Studie wurde unter Verwendung von stabil transfizierten humanen Osteosarkoma-Zellen (U-2 OS) mit konstitutiver Expression von GFP (grün fluoreszierendes Protein)-markiertem FOXO1 und humanen Hepatoma-Zellen (HepG2) die Wirkung von Benzylisothiocyanat (BITC), dessen Vorstufe Benzylglukosinolat aus Nasturtium isoliert wurde, in Zellkulturen evaluiert wie Modulationen der i) Insulin-Signal-Kaskade, ii) intrazellulären Lokalisation von FOXO1 und iii) Expression beteiligter Proteine am Glucose Metabolismus, der ROS Detoxifikation, Zellzyklus-Fixierung und DNA-Reparatur. BITC erzeugte oxidativen Stress und induzierte als Antwort darauf eine Translokation von FOXO1 aus dem Zytoplasma in den Zellkern antagonisierend zum Insulin-Effekt. Eine Stimultion mit BITC war in der Lage, die Expression von Enzymen der Gluconeogenese herunter zu regulieren, was als antidiabetogener Effekt betrachtet werden kann, eine antioxidative Resistenz durch Induktion der Mangan-Superoxid-Dismutase (MnSOD) und entgiftender Enzyme zu erzeugen, Autophagie zu modulieren durch Induktion von BECLIN1 und Herunterregulation des „mammalian target of rapamycin complex1 (mTORC1)-Stoffwechselwegs, den Zellzyklus zu fixieren und DNA-Reparatur zu induzieren durch Hochregulation des Cyclin- abhängigen Kinase- Inhibitors p21CIP und GADD45 (growth arrest and DNA damage repair). Mit Ausnahme des nuklearen Faktors (erythroid derived)-like2 (NRF2) und dessen Einfluss auf die Genexpression von Entgiftungsenzymen waren alle beobachteten Effekte unabhängig von FOXO1, Proteinkinase B (PKB/AKT) und der NAD-abhängigen Deacetylase Sirtuin-1 (SIRT1). Die gegenwärtige Studie liefert Anhaltspunkte dafür, dass Isothiocayanate neben dem antikanzerogenen Potential eine Rolle bei der Prävention von Typ 2 Diabetes spielen könnten. BITC-Stimulationen ahmen einen Fastenzustand nach, in dem kein Insulin-Signal ausgelöst wird, FOXO Proteine im Zellkern verbleiben und die Expression von Target-Genen modulieren, mit dem Vorteil einer Herunterregulation der Glukoneogenese anstelle seiner Zunahme. Diese Effekte legen nahe, dass BITC als vielversprechende Substanz zur Prävention und Behandlung von Typ 2 Diabetes angesehen werden könnte. Deshalb benötigen die Faktoren, die dessen modulatorische Effekte hervorrufen, weitere Untersuchungen.

The overall purpose of this thesis was to identify determinants of quality of life in adults with diabetes mellitus. This thesis consists of two studies. The first study tested a comprehensive model which comprised of personal, medical and lifestyle factors to explain quality of life in adults with type 2 diabetes. The model was tested with two concepts of quality of life: health-related quality of life and life satisfaction. The second study (1) tested the comprehensive model in adults with type 1 diabetes; and, (2) examined the interaction effects of diabetes type (i.e., type 1 diabetes /type 2 diabetes) on significant determinants of quality of life in the combined type 1 and type 2 diabetes group. The findings of this study identified subgroups that may be at risk for impaired quality of life and topics that require further investigation.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.

Type 2 diabetes mellitus (T2DM) is one of the leading causes of death from worldwide non-communicable diseases. The prevalence of diabetes in the Mexico (MX)-United States border states exceeds the national rate in both countries. The economic burden of diabetes, due to decreased productivity, disability, and medical costs, is staggering and increases significantly when T2DM-related complications occur. The purpose of this study was to use a modified behavioral risk factor surveillance system (BRFSS) to describe the T2DM self-management behaviors, diabetes care, and health perception of a convenience sample of adults with T2DM in Monterrey, MX. This cross-sectional study design, with convenience sampling, was conducted with a convenience sample (n = 351) of adults in the metropolitan area of Monterrey, MX who self-reported a diagnosis of T2DM. Potential participants were recruited from local supermarkets. Twenty-six diabetes and health-related items were selected from the BRFSS and administered in face-to-face interviews by trained data collectors. Data analysis was conducted using descriptive statistics. The mean age was 47 years, and the mean length of time with T2DM was 12 years. The majority was taking oral medication and 34% required insulin. Daily self-monitoring of feet was performed by 56% of the participants; however, only 8.8% engaged in blood glucose self-monitoring. The mean number of health-care provider visits was 9.09 per year, and glycated hemoglobin level (HbA1c) was assessed 2.6 times per year. Finally, only 40.5% of the participants recalled having a dilated eye exam. We conclude the modified BRFSS survey administered in a face-to-face interview format is an appropriate tool for assessing engagement in T2DM self-management behaviors, diabetes care, and health perception. Extension of the use of this survey in a more rigorous design with a larger scale survey is encouraged.