Rebecca L Hull

Rebecca L Hull
  • Ph.D.
  • University of Washington

About

120
Publications
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11,394
Citations
Current institution
University of Washington

Publications

Publications (120)
Article
Hypercholesterolemia is often observed in individuals with type 2 diabetes. Cholesterol accumulation in subcellular compartments within islet β-cells can result in insulin secretory dysfunction, which is a key pathological feature of diabetes. Previously, we demonstrated that expression of the mitochondrial cholesterol transport protein, steroidoge...
Article
The pancreatic islet vasculature comprises microvascular endothelial cells surrounded by mural cells (pericytes). Both cell types support the islet by providing (1) a conduit for delivery and exchange of nutrients and hormones; (2) paracrine signals and extracellular matrix (ECM) components that support islet development, architecture, and endocrin...
Article
Full-text available
Insulin secretion is impaired in individuals with cystic fibrosis (CF), contributing to high rates of CF-related diabetes (CFRD) and substantially increasing disease burden. To develop improved therapies for CFRD, better knowledge of pancreatic pathology in CF is needed. Glucagon like peptide-1 (GLP-1) from islet α cells potentiates insulin secreti...
Article
Full-text available
Aims/hypothesis Apart from its fibrinolytic activity, the tissue plasminogen activator (tPA)/plasmin system has been reported to cleave the peptide amyloid beta, attenuating brain amyloid deposition in Alzheimer’s disease. As aggregation of human islet amyloid polypeptide (hIAPP) is toxic to beta cells, we sought to determine whether activation of...
Article
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Cystic fibrosis (CF) is a multi-organ disease caused by loss-of-function mutations in CFTR (which encodes the CF transmembrane conductance regulator ion channel). Cystic fibrosis related diabetes (CFRD) occurs in 40-50% of adults with CF and is associated with significantly increased morbidity and mortality. CFRD arises from insufficient insulin re...
Article
Hypercholesterolemia is common in diabetes. We sought to determine whether cholesterol (Chol) can exacerbate impaired insulin secretion in islets from a mouse model of mild β-cell dysfunction. To induce β-cell dysfunction, C57BL/6J male mice were treated with low-dose (30 mg/kg, i.p.) streptozotocin (STZ) or vehicle (VEH) once daily on 3 consecutiv...
Article
Cystic fibrosis (CF) is a recessive disorder arising from mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CFTR is expressed in numerous tissues, with high expression in the airways, small and large intestine, pancreatic and hepatobiliary ducts, and male reproductive tract. CFTR loss in these ti...
Article
Cystic fibrosis (CF) is a recessive disorder arising from mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CFTR is expressed in numerous tissues, with high expression in the airways, small and large intestine, pancreatic and hepatobiliary ducts, and male reproductive tract. CFTR loss in these ti...
Article
The year 2023 marks 100 years since publication of the first report of a hyperglycemic factor in pancreatic extracts which CP Kimball and John R Murlin named glucagon (from GLUCose AGONist). Glucagon has a range of profound effects on metabolism including, but not limited to, stimulation of hepatic glucose production. Dysregulation of glucagon secr...
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The Integrated Physiology of the Exocrine and Endocrine Compartments in Pancreatic Diseases workshop was a 1.5-day scientific conference at the National Institutes of Health (Bethesda, MD) that engaged clinical and basic science investigators interested in diseases of the pancreas. This report provides a summary of the proceedings from the workshop...
Preprint
Full-text available
Pancreatic β-cell dysfunction and death are central to the pathogenesis of type 2 diabetes (T2D). We have identified a novel role for the inflammatory extracellular matrix polymer hyaluronan (HA) in this pathophysiology. Low levels of HA are present in healthy pancreatic islets. However, HA substantially accumulates in cadaveric islets of human T2D...
Article
The "Integrated Physiology of the Exocrine and Endocrine Compartments in Pancreatic Diseases" Workshop was a 1.5-day scientific conference at the National Institutes of Health (Bethesda, MD) that engaged clinical and basic science investigators interested in diseases of the pancreas. This report summarizes the workshop proceedings. The goal of the...
Article
Full-text available
Aims/hypothesis The islet vasculature, including its constituent islet endothelial cells, is a key contributor to the microenvironment necessary for normal beta cell health and function. In type 2 diabetes, islet amyloid polypeptide (IAPP) aggregates, forming amyloid deposits that accumulate between beta cells and islet capillaries. This process is...
Article
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Treatment of heart failure with the angiotensin receptor-neprilysin inhibitor sacubitril/valsartan improved glycemic control in individuals with type 2 diabetes. The relative contribution of neprilysin inhibition versus angiotensin II receptor antagonism to this glycemic benefit remains unknown. Thus, we sought to determine the relative effects of...
Article
Glucose intolerance and insulin deficiency are common features of cystic fibrosis (CF) , with nearly half of adult CF patients developing CF-related diabetes (CFRD) , but the underlying pathophysiology remains poorly understood. Extensive destruction of the exocrine pancreas occurs in most CF patients. However, islets are still readily detectable,...
Article
Peri-islet glial cells (PIGCs) are positioned to control neuronal-endocrine-vascular cell communication within the islet, but their role in islet cell function is not known. Hypothalamic glial cells become reactive in response to high fat diet (HFD) feeding and are implicated in the pathogenesis of obesity and type 2 diabetes. We hypothesize that m...
Article
Diabetes is associated with elevated plasma cholesterol (Chol) , with its intracellular accumulation resulting in β-cell dysfunction. In steroidogenic tissues, StAR facilitates Chol transport from the outer to inner mitochondrial membrane for subsequent metabolism. We have shown that StAR is expressed in β cells and its upregulation increases mitoc...
Article
Type 2 diabetes is associated with upregulation of neprilysin, a peptidase capable of cleaving glucoregulatory peptides such as glucagon-like peptide-1 (GLP-1). In humans, use of the neprilysin inhibitor sacubitril in combination with an angiotensin II receptor blocker was associated with increased plasma GLP-1 levels and improved glycemic control....
Article
Apoptosis repressor with caspase recruitment domain (ARC) is an endogenous inhibitor of cell death signaling that is expressed in insulin-producing β-cells. ARC has been shown to reduce β-cell death in response to diabetogenic stimuli in vitro, but its role in maintaining glucose homeostasis in vivo has not been fully established. Here we examined...
Article
While statin therapy reduces plasma cholesterol, it also impairs β-cell function and increases the risk of developing diabetes. We have shown that the cholesterol transport protein STAR is synthesized in β cells and its upregulation results in increased β-cell mitochondrial cholesterol content, producing β-cell dysfunction. Given statins’ role in c...
Article
Islet endothelial cells produce paracrine factors important for islet beta-cell function and survival. Under conditions of type 2 diabetes, islet endothelial cells exhibit a dysfunctional phenotype including increased expression of genes involved in cellular adhesion and inflammation. We sought to determine whether treatment of hyperglycemia with t...
Article
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Aims/hypothesis: Aggregation of the beta cell secretory product human islet amyloid polypeptide (hIAPP) results in islet amyloid deposition, a pathological feature of type 2 diabetes. Amyloid formation is associated with increased levels of islet IL-1β as well as beta cell dysfunction and death, but the mechanisms that promote amyloid deposition i...
Article
Full-text available
The islets of Langerhans are well embedded within the exocrine pancreas (the latter comprised of ducts and acini), but the nature of interactions between these pancreatic compartments and their role in determining normal islet function and survival are poorly understood. However, these interactions appear to be critical, as when pancreatic exocrine...
Article
Islet amyloid deposition and reduced ß-cell mass are pathologic hallmarks of type 2 diabetes. Amyloid deposits contain the 37 amino acid hIAPP, aggregation of which is toxic to ß cells. The 20-29 amino acid region of the peptide is known to confer its amyloidogenic potential. We previously reported that plasmin, a fibrinolytic protease, cleaves hIA...
Article
Apoptosis repressor with caspase recruitment domain (ARC) is an endogenous inhibitor of apoptosis signaling. We previously showed ARC is expressed in β cells and ameliorates amyloid-induced β-cell death in vitro. More recently, we found that wild type (WT) and whole-body ARC knockout (KO) mice on an FVB background fed a normal chow diet exhibit no...
Article
In type 2 diabetes, HbA1c decreases upon treatment of heart failure with the angiotensin receptor-neprilysin (NEP) inhibitor LCZ696 (LCZ). We sought to determine whether the components of LCZ, the NEP inhibitor sacubitril (SAC) and angiotensin receptor blocker valsartan (VAL), enhance insulin secretion and if so, their effects are additive when com...
Article
In type 2 diabetes (T2D), aggregation of human islet amyloid polypeptide (hIAPP) occurs within the islet extracellular matrix (ECM) and is toxic to β cells. We recently showed that hIAPP aggregation also induces a pro-inflammatory response in islet endothelial cells (ECs). In most tissues, this inflammatory response in ECs is mediated by upregulati...
Article
Star, which we have shown to be produced in beta cells, is responsible for transport of cholesterol into mitochondria for the production of steroids. We previously found that Star is upregulated with islet amyloid deposition and this is associated with mitochondrial dysfunction. In steroidogenic tissues, StAR transcription is acutely regulated by c...
Article
Islet amyloid is a pathologic feature of type 2 diabetes (T2D) that is associated with β-cell loss and dysfunction. These amyloid deposits form via aggregation of the β-cell secretory product islet amyloid polypeptide (IAPP) and contain other molecules including the heparan sulfate proteoglycan perlecan. Perlecan has been shown to bind amyloidogeni...
Article
Type 2 diabetes is characterized by islet amyloid deposition, which is associated with β-cell loss. hIAPP is the unique peptide component of these deposits. We previously found that expression of tPA, the initiator of fibrinolysis, is upregulated in islets by amyloid formation in vitro. As plasmin, the proteolytic product of tPA activity, cleaves A...
Article
StAR is a cholesterol transport protein that transports cholesterol from the cytoplasm into the mitochondrial matrix for further metabolism by CYP enzymes. Depending on the CYP expressed, this results in production of corticosteroids, gonadal steroids, neurosteroids or oxysterols. These products generally exert positive effects on cellular health a...
Article
Islet endothelial cells [ECs] produce numerous factors that support normal β-cell function and survival. Under diabetic conditions, islet ECs develop an activated (pro-inflammatory, pro-adhesive) phenotype which contributes to β-cell failure. In human type 2 diabetes [T2D], aggregation of the β-cell product, islet amyloid polypeptide [IAPP], result...
Article
Aggregation of the β-cell secretory product human islet amyloid polypeptide (hIAPP) results in islet amyloid deposition as observed in type 2 diabetes (T2D). Formation of islet amyloid is associated with increased expression of proinflammatory cytokines and contributes to β-cell dysfunction and death. We previously showed that physiological levels...
Article
In cystic fibrosis (CF), ductal plugging and acinar loss result in rapid decline of exocrine pancreatic function. This destructive process results in remodeled islets, with only a modest reduction in insulin producing β cells. However, β-cell function is profoundly impaired, with decreased insulin release and abnormal glucose tolerance being presen...
Article
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Aims/hypothesis: Islet amyloid deposits contribute to beta cell dysfunction and death in most individuals with type 2 diabetes but non-invasive methods to determine the presence of these pathological protein aggregates are currently not available. Therefore, we examined whether florbetapir, a radiopharmaceutical agent used for detection of amyloid...
Article
Islet amyloid deposition occurs in the majority of individuals with type 2 diabetes (T2D) and contributes to beta-cell death by mechanisms which are not fully understood. Necroptosis is an immunogenic form of cell death dependent on tumor necrosis factor receptor 1 (TNFR1) signaling, receptor interacting protein kinase 3 (RIPK3) oligomerization, an...
Article
Islet amyloid deposition is a pathologic hallmark of type 2 diabetes (T2D) resulting in β-cell loss. tPA, an activator of fibrinolysis, attenuates brain amyloid deposition associated with Alzheimer’s disease. Based on RNAseq analysis to identify genes upregulated by islet amyloid, we found tPA to be specifically increased in islets with amyloid dep...
Article
Islet endothelial dysfunction occurs in diabetic mice and results in impaired insulin release in vitro. Previously, we found that 12-week treatment of db/db mice with the SGLT2 inhibitor empagliflozin (EMPA) improved islet endothelial dysfunction. Here, we determined if this occurs with shorter treatment duration, is associated with increased insul...
Article
Neprilysin (NEP) is an endopeptidase known to modulate nervous, cardiovascular, and immune systems via inactivation of regulatory peptides. In addition, it may also contribute to impaired glucose homeostasis as observed in type 2 diabetes (T2D). Specifically, we and others have shown that NEP is upregulated under conditions associated with T2D, whe...
Article
Objective: Cystic fibrosis-related diabetes (CFRD) is a common complication of cystic fibrosis (CF), increasing patient morbidity and mortality. Poor understanding of CFRD pathogenesis limits the development of targeted therapies to treat and/or prevent the disease. The aim of this study was to evaluate islet pathology, specifically, inflammation,...
Article
Full-text available
Islet amyloid is present in more than 90% of individuals with type 2 diabetes, where it contributes to β-cell apoptosis and insufficient insulin secretion. Apoptosis repressor with caspase recruitment domain (ARC) binds and inactivates components of the intrinsic and extrinsic apoptosis pathways, and was recently found to be expressed in islet β ce...
Article
Full-text available
The pancreatic islet is highly vascularised, with an extensive capillary network. In addition to providing nutrients and oxygen to islet endocrine cells and transporting hormones to the peripheral circulation, islet capillaries (comprised primarily of islet endothelial cells) are an important source of signals that enhance survival and function of...
Article
Mouse models are widely used for elucidating mechanisms underlying type 2 diabetes. Genetic background profoundly affects metabolic phenotype; therefore selecting the appropriate model is critical. While variability in metabolic responses between mouse strains is now well-recognized, it also occurs within C57BL/6 mice, of which several substrains e...
Article
Islet endothelial cells produce paracrine factors that support β-cell function and growth. Endothelial dysfunction underlies diabetic microvascular complications; thus we hypothesized that in diabetes, islet endothelial cells become dysfunctional and this may contribute to β-cell secretory dysfunction. Islets/islet endothelial cells were isolated f...
Article
Full-text available
Aims/hypothesis The S20G human islet amyloid polypeptide (hIAPP) substitution is associated with an earlier onset of type 2 diabetes in humans. Studies of synthetic S20G hIAPP in cell-free systems and immortalised beta cells have suggested that this may be due to increased hIAPP amyloidogenicity and cytotoxicity. Thus, using primary islets from mic...
Article
Full-text available
Islet amyloid deposition in human type 2 diabetes results in β-cell loss. These amyloid deposits contain the unique amyloidogenic peptide human islet amyloid polypeptide (hIAPP), which is also a known substrate of the protease insulin-degrading enzyme (IDE). While IDE inhibition has recently been demonstrated to improve glucose metabolism in mice,...
Article
Full-text available
In humans, the glucagon response to moderate-marked insulin-induced hypoglycemia (IIH) is largely mediated by the autonomic nervous system. Because this glucagon response is impaired early in type 1 diabetes, we sought to determine if these patients, like animal models of autoimmune diabetes, have an early and severe loss of islet sympathetic nerve...
Article
Full-text available
Deposition of human islet amyloid polypeptide (hIAPP, also known as amylin) as islet amyloid is a characteristic feature of the pancreas in type 2 diabetes, contributing to increased β-cell apoptosis and reduced β-cell mass. Matrix metalloproteinase-9 (MMP-9) is active in islets and cleaves hIAPP. We investigated whether hIAPP fragments arising fro...
Article
In the Editorial, Histochemical Insights into Pancreatic Islet Biology, by Rebecca L. Hull and Denis G. Baskin, J Histochem Cytochem, August 2015, 63:541-542, there were several errors in the references section. (DOI: 10.1369/0022155415586442) First, the following references did not include page numbers: Asadi A, Bruin JE, Kieffer TJ (2015). Charac...
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Under fasting conditions, increases in circulating concentrations of glucagon maintain glucose homeostasis via the induction of hepatic gluconeogenesis. Triggering of the cAMP pathway in hepatocytes stimulates the gluconeogenic program via the PKA-mediated phosphorylation of CREB and dephosphorylation of the cAMP regulated CREB coactivators CRTC2 a...
Article
Hyaluronan (HA) is an extracellular matrix (ECM) component that is present in mouse and human islet ECM. HA is localized in peri-islet and intra-islet regions adjacent to microvessels. HA normally exists in a high molecular weight form, which is anti-inflammatory. However, under inflammatory conditions, HA is degraded into fragments that are proinf...
Article
Human and rodent islets differ substantially in several features, including architecture, cell composition, gene expression and some aspects of insulin secretion. Mouse pancreatic islets are highly vascularized with interactions between islet endothelial and endocrine cells being important for islet cell differentiation and function. To determine w...
Chapter
The pancreas comprises exocrine and endocrine compartments, with the latter comprising the pancreatic islet with its endocrine (?, ?, ?, F, and ?) cells along with extensive vascular and neural supply. The morphologic arrangement of cell types within the islet appears to be critical for its normal endocrine function. In both type 1 and type 2 diabe...
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Aims/hypothesis: Amyloid deposition and inflammation are characteristic of islet pathology in type 2 diabetes. The aim of this study was to determine whether islet amyloid formation is required for the development of islet inflammation in vivo. Methods: Human islet amyloid polypeptide transgenic mice and non-transgenic littermates (the latter in...
Article
The DPP-4 inhibitor sitagliptin is an attractive therapy for diabetes as it increases insulin release and may preserve beta-cell mass. However, sitagliptin also increases beta-cell release of human islet amyloid polypeptide (hIAPP), the peptide component of islet amyloid, which is co-secreted with insulin. Thus, sitagliptin treatment may promote is...
Article
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Previous studies on isolated islets have demonstrated tight coupling between calcium (Ca) influx and oxygen consumption rate (OCR) that is correlated with insulin secretion rate (ISR). To explain these observations, we have proposed a mechanism whereby the activation of a highly energetic process (Ca/metabolic coupling process [CMCP]) by Ca mediate...
Article
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Deposition of islet amyloid polypeptide (IAPP) as amyloid is a pathological hallmark of the islet in type 2 diabetes, which is toxic to β-cells. We previously showed that the enzyme neprilysin reduces islet amyloid deposition and thereby reduces β-cell apoptosis, by inhibiting fibril formation. Two other enzymes, matrix metalloproteinase (MMP)-2 an...
Article
Full-text available
Aggregation of human islet amyloid polypeptide (hIAPP) as islet amyloid is associated with increased beta cell apoptosis and reduced beta cell mass in type 2 diabetes. Islet amyloid formation induces oxidative stress, which contributes to beta cell apoptosis. The cJUN N-terminal kinase (JNK) pathway is a critical mediator of beta cell apoptosis in...
Article
In human islet transplantation, insulin independence decreases over time. We previously showed that amyloid deposition following transplantation of islets from human islet amyloid polypeptide (hIAPP) transgenic mice resulted in ß-cell loss and that rosiglitazone treatment decreased islet amyloid deposition and preserved ß-cell area in the endogenou...
Article
Full-text available
Islet amyloid, a pathologic feature of type 2 diabetes, contains the islet β-cell peptide islet amyloid polypeptide (IAPP) as its unique amyloidogenic component. Islet amyloid also contains heparan sulfate proteoglycans (HSPGs) that may contribute to amyloid formation by binding IAPP via their heparan sulfate (HS) chains. We hypothesized that β cel...
Article
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The pancreatic islet comprises endocrine, vascular, and neuronal cells. Signaling among these cell types is critical for islet function. The extracellular matrix (ECM) is a key regulator of cell-cell signals, and while some islet ECM components have been identified, much remains unknown regarding its composition. We investigated whether hyaluronan,...
Article
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Type 1 diabetes (T1D) is a disease that in most individuals results from autoimmune attack of a single tissue type, the pancreatic islet. A fundamental, unanswered question in T1D pathogenesis is how the islet tissue environment influences immune regulation. This crosstalk is likely to be communicated through the extracellular matrix (ECM). Here, w...
Article
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In type 2 diabetes, aggregation of islet amyloid polypeptide (IAPP) into amyloid is associated with beta cell loss. As IAPP is co-secreted with insulin, we hypothesised that IAPP secretion is necessary for amyloid formation and that treatments that increase insulin (and IAPP) secretion would thereby increase amyloid formation and toxicity. We also...
Article
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Amyloid deposition and reduced β-cell mass are pathological hallmarks of the pancreatic islet in type 2 diabetes; however, whether the extent of amyloid deposition is associated with decreased β-cell mass is debated. We investigated the possible relationship and, for the first time, determined whether increased islet amyloid and/or decreased β-cell...
Article
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Interleukin 1β (IL-1β) is an important inflammatory mediator of type 2 diabetes. Here we show that oligomers of islet amyloid polypeptide (IAPP), a protein that forms amyloid deposits in the pancreas during type 2 diabetes, triggered the NLRP3 inflammasome and generated mature IL-1β. One therapy for type 2 diabetes, glyburide, suppressed IAPP-media...
Article
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Deposition of islet amyloid polypeptide (IAPP) as islet amyloid in type 2 diabetes contributes to loss of beta-cell function and mass, yet the mechanism for its occurrence is unclear. Neprilysin is a metallopeptidase known to degrade amyloid in Alzheimer disease. We previously demonstrated neprilysin to be present in pancreatic islets and now sough...
Article
Full-text available
Type 2 diabetes is a progressive disease characterised by islet amyloid deposits in the majority of patients. Amyloid formation is considered a significant factor in deterioration of islet function and reduction in beta cell mass, and involves aggregation of monomers of the normally soluble beta cell peptide, human islet amyloid polypeptide (hIAPP)...
Article
Full-text available
Supraphysiological levels of the amyloidogenic peptide human islet amyloid polypeptide have been associated with beta cell endoplasmic reticulum (ER) stress. However, in human type 2 diabetes, levels of human IAPP are equivalent or decreased relative to matched controls. Thus, we sought to investigate whether ER stress is induced during amyloidogen...
Article
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The critical role of the beta cell in the pathogenesis of type 2 diabetes is now well established. When examined in patients with type 2 diabetes and individuals at increased risk, reductions in beta cell mass and abnormalities of beta cell function can both be demonstrated. The question of whether one alone is sufficient or both are necessary for...
Article
Full-text available
Islet amyloid in type 2 diabetes contributes to loss of beta cell mass and function. Since islets are susceptible to oxidative stress-induced toxicity, we sought to determine whether islet amyloid formation is associated with induction of oxidative stress. Human islet amyloid polypeptide transgenic and non-transgenic mouse islets were cultured for...
Article
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Islet transplantation is a potential cure for diabetes; however, rates of graft failure remain high. The aim of the present study was to determine whether amyloid deposition is associated with reduced beta cell volume in islet grafts and the recurrence of hyperglycaemia following islet transplantation. We transplanted a streptozotocin-induced mouse...
Article
Full-text available
Deposition of islet amyloid polypeptide (IAPP) as amyloid in the pancreatic islet occurs in approximately 90% of individuals with Type 2 diabetes and is associated with decreased islet beta-cell mass and function. Human IAPP (hIAPP), but not rodent IAPP, is amyloidogenic and toxic to islet beta-cells. In addition to IAPP, islet amyloid deposits con...
Article
The Cockcroft-Gault and the Modification of Diet in Renal Disease (MDRD) Study equations have not been validated in Asian Americans with varying degrees of glucose tolerance. We compared both equations to 24-h urinary creatinine clearance, the latter as a standard measurement of glomerular filtration rate (GFR), in 398 Japanese Americans (62.1+/-5....
Article
Islet amyloid contributes to the loss of beta-cell mass in type 2 diabetes. To examine the roles of glucose and time on amyloid formation, we developed a rapid in vitro model using isolated islets from human islet amyloid polypeptide (hIAPP) transgenic mice. Islets from hIAPP transgenic and non-transgenic mice were cultured for up to 7 days with ei...
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The relative roles of insulin resistance and beta-cell dysfunction in the pathogenesis of impaired glucose tolerance (IGT) and type 2 diabetes are debated. First-degree relatives of individuals with type 2 diabetes are at increased risk of developing hyperglycemia. We evaluated the evolution of insulin sensitivity, beta-cell function, glucose effec...
Article
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Islet amyloid contributes to loss of beta-cell mass and function in type 2 diabetes. It is poorly understood how the building block of amyloid, islet amyloid polypeptide (IAPP), misfolds and accumulates within the islet to contribute to cellular dysfunction. We sought to determine whether neprilysin, an amyloid-degrading enzyme, is present in islet...
Article
Objective Pancreatic polypeptide (PP) is a 36-amino acid peptide produced by the F-cells of the pancreas, the plasma concentration of which has been used as a marker of parasympathetic activity. Recent work in rodents suggests that both sympathetic and parasympathetic input to adipose tissue may regulate its endocrine function and play a role in in...
Article
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Obesity is associated with an increased risk of developing insulin resistance and type 2 diabetes. In obese individuals, adipose tissue releases increased amounts of non-esterified fatty acids, glycerol, hormones, pro-inflammatory cytokines and other factors that are involved in the development of insulin resistance. When insulin resistance is acco...
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We sought to determine whether a history of gestational diabetes mellitus (GDM) further increases the risk of cardiovascular disease (CVD) in parous women with first-degree relatives with type 2 diabetes. Women with (n = 332) and without (n = 663) a history of GDM were compared regarding 1) the revised National Cholesterol Education Program Adult T...
Article
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To determine whether the hyperbolic relationship between insulin sensitivity and the acute insulin response to glucose (AIRg) exists in subjects with impaired fasting glucose (IFG) or decreased glucose tolerance. We studied 219 healthy subjects (88 male and 131 female subjects, aged 26-75 years) with fasting plasma glucose (FPG) <6.11 mmol/l. Subje...
Article
Background Central adiposity is known to be associated with decreased glucose tolerance and has been suggested to be associated with reduced glomerular filtration rate (GFR). Methods To determine whether abnormalities of GFR occur in the early stages of glucose intolerance and are related to visceral adiposity, we examined 406 Japanese Americans (...
Article
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The aim of this study was to further elucidate the relationship between resistin and insulin sensitivity, body fat distribution and the metabolic syndrome in humans. We measured plasma resistin levels in 177 non-diabetic subjects (75 male, 102 female; age 32-75 years). BMI, waist circumference, blood pressure, lipids, glucose, plasminogen-activator...
Article
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The increasing production of genetically-modified mouse models has necessitated studies to determine the inherent physiological characteristics of commonly used mouse strains. In this study we examined insulin secretory function in response to an intravenous bolus of glucose or glucose plus arginine in anesthetized C57BL/6, DBA/2 and 129T2 mice fed...
Article
Genetic background is important in determining susceptibility to metabolic abnormalities such as insulin resistance and beta-cell dysfunction. Islet amyloid is associated with reduced beta-cell mass and function and develops in the majority of our C57BL/6J x DBA/2J (F(1)) male human islet amyloid polypeptide (hIAPP) transgenic mice after 1 yr of in...
Article
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Increased dietary fat intake is associated with obesity and insulin resistance, but studies have shown that the subsequent increase in insulin release is not appropriate for this obesity-induced insulin resistance. We therefore sought to determine whether the impaired beta cell adaptation is due to inadequate expansion of the beta cell population o...

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