Christophe Bonny
Jan 1, 2001; 50:77-82
Islet Studies

Joachim Spranger
Mar 1, 2003; 52:812-817
Pathophysiology

G Perseghin
Aug 1, 1999; 48:1600-1606
Articles

Miriam Cnop
Dec 1, 2005; 54:S97-S107
Section III: Inflammation and beta-Cell Death

T Inoguchi
Nov 1, 2000; 49:1939-1945
Articles

Eve Van Cauter
Mar 1, 1992; 41:368-377
Original Article

Ralph A. DeFronzo
Apr 1, 2009; 58:773-795
Banting Lecture

D A Pan
Jun 1, 1997; 46:983-988
Original Article

D Koya
Jun 1, 1998; 47:859-866
Articles

G Xu
Dec 1, 1999; 48:2270-2276
Articles

Andreas Festa
Apr 1, 2002; 51:1131-1137
Complications

The Diabetes Control and Complications Trial Research Group
Aug 1, 1995; 44:968-983
Original Article

David E. Cummings
Aug 1, 2001; 50:1714-1719
Rapid Publications

Thomas A. Buchanan
Sep 1, 2002; 51:2796-2803
Pathophysiology

John W Baynes
Apr 1, 1991; 40:405-412
Perspectives in Diabetes

Ralph A DeFronzo
Jun 1, 1988; 37:667-687
Lilly Lecture 1987

Steven E Kahn
Nov 1, 1993; 42:1663-1672
Original Article

David E. Kelley
Oct 1, 2002; 51:2944-2950
Metabolism and Signal Transduction

HE Hohmeier
Mar 1, 2000; 49:424-430
Articles

National Diabetes Data Group
Dec 1, 1979; 28:1039-1057
Articles

Alexandra E. Butler
Jan 1, 2003; 52:102-110
Islet Studies

This study aims to model genetic, immunologic, metabolomics, and proteomic biomarkers for development of islet autoimmunity (IA) and progression to type 1 diabetes in a prospective high-risk cohort. We studied 67 children: 42 who developed IA (20 of 42 progressed to diabetes) and 25 control subjects matched for sex and age. Biomarkers were assessed at four time points: earliest available sample, just prior to IA, just after IA, and just prior to diabetes onset. Predictors of IA and progression to diabetes were identified across disparate sources using an integrative machine learning algorithm and optimization-based feature selection. Our integrative approach was predictive of IA (area under the receiver operating characteristic curve [AUC] 0.91) and progression to diabetes (AUC 0.92) based on standard cross-validation (CV). Among the strongest predictors of IA were change in serum ascorbate, 3-methyl-oxobutyrate, and the PTPN22 (rs2476601) polymorphism. Serum glucose, ADP fibrinogen, and mannose were among the strongest predictors of progression to diabetes. This proof-of-principle analysis is the first study to integrate large, diverse biomarker data sets into a limited number of features, highlighting differences in pathways leading to IA from those predicting progression to diabetes. Integrated models, if validated in independent populations, could provide novel clues concerning the pathways leading to IA and type 1 diabetes.

Western Bureau: Some displaced Iberostar employees in Rose Hall, St James, are angry with their employer, charging that they have been unable to benefit from the Government’s COVID-19 relief programme because of the hotel’s failure to pay over...

Days after The Gleaner reported a clarion call from Port Maria Mayor Richard Creary for the quarantine of St Mary communities owing to growing concerns about the spread of COVID-19 in the parish, the Government responded with the lockdown of three...

The wet weather last Saturday (May 2) could not dampen the spirits of award-winning gospel artiste and ordained evangelist Kevin Downswell as he ventured into the St Catherine community of Central Village, where he spent some of his formative years...

Director of the Pan American Health Organization (PAHO), Dr Carissa F. Etienne, today called for accelerated and expanded testing for COVID-19 in countries of the Americas. “We need a clearer view of where the virus is circulating and how...

PORT OF SPAIN, Trinidad, CMC – Prime Minister Dr Keith Rowley Saturday dismissed as a “dishonest last gasp and gamble of a dangerously delusional woman” a statement by Opposition Leader Kamla Persad Bissessar calling for him...

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Glucagon-like peptide 1 (GLP-1) mimetics are effective drugs for treatment of type 2 diabetes, and there is consequently extensive interest in increasing endogenous GLP-1 secretion and L-cell abundance. Here we identify G-protein–coupled bile acid receptor 1 (GPBAR1) as a selective regulator of intestinal L-cell differentiation. Lithocholic acid and the synthetic GPBAR1 agonist, L3740, selectively increased L-cell density in mouse and human intestinal organoids and elevated GLP-1 secretory capacity. L3740 induced expression of Gcg and transcription factors Ngn3 and NeuroD1. L3740 also increased the L-cell number and GLP-1 levels and improved glucose tolerance in vivo. Further mechanistic examination revealed that the effect of L3740 on L cells required intact GLP-1 receptor and serotonin 5-hydroxytryptamine receptor 4 (5-HT4) signaling. Importantly, serotonin signaling through 5-HT4 mimicked the effects of L3740, acting downstream of GLP-1. Thus, GPBAR1 agonists and other powerful GLP-1 secretagogues facilitate L-cell differentiation through a paracrine GLP-1–dependent and serotonin-mediated mechanism.

Beat reporter Mark Sheldon answers questions about David Bell's managing style, free agents and who will play center field.

It wasn't just that there were new faces when Reds camp opened Tuesday with the reporting of pitchers and catchers for physicals, there was a different vibe that could be felt in the hallways and clubhouse.

As Reds Spring Training opened with pitchers and catchers reporting for physicals on Tuesday, new manager David Bell was already be tasked with many responsibilities. But there will be one that looms largest. Following five years out of the postseason, including the past four with more than 90 losses, Bell must restore a culture of winning.

Wednesday marked the first time that manager David Bell got to address Reds players as a group when he spoke to pitchers and catchers ahead of their first workout of Spring Training. Bell put a lot of thought into what he wanted to tell them.

Unlike recent Reds Spring Trainings, much of the drama about who would comprise the rotation was already removed on the first day of camp. That's when manager David Bell revealed the starting five would likely be -- in no particular order -- Sonny Gray, Tanner Roark, Alex Wood, Luis Castillo and Anthony DeSclafani.

As the Reds consider their regular center-fielder options, they are not just humoring career infielder Nick Senzel by letting him compete for the spot. Senzel believes he can do it. Perhaps more importantly, so does new manager David Bell.

Reds manager David Bell has great corner outfield depth, but he doesn't have a regular center fielder. Determining who will get to play where and sorting out the log jam should be a challenge for Bell in his first season as a skipper in the big leagues.

Since Jesse Winker suffered a season-ending shoulder injury on July 23, he's gained a lot of company in the corner-outfield spots.

THE EDITOR, Madam: “WHY CAN’T vehicle registration be renewed online?” That’s the question asked by Dr Rory Dixon, senior medical officer, Sir John Golding Rehabilitation Centre, in his letter to The Gleaner on Tuesday, May 5. The first paragraph...

At the outset, author Ivy Slater shares the existential crisis that spurred her to change careers. Slater’s psychosocial experience after the passing of her father and the stagnation she experienced at her printing business proved exhaustively...

She’s what you’d term the consummate creative – through the sensory ‘dry land tourist’ tales of her ‘Right Roun Di Corna’ blog to the pieces in her JadeLauren eyewear brand, Lauren Campbell is colouring the world with beauty, life, and bomb...

Fasting hyperinsulinemia precedes the development of type 2 diabetes. However, it is unclear whether fasting insulin hypersecretion is a primary driver of insulin resistance or a consequence of the progressive increase in fasting glycemia induced by insulin resistance in the prediabetic state. Herein, we have discovered a mechanism that specifically regulates non–glucose-stimulated insulin secretion (NGSIS) in pancreatic islets that is activated by nonesterified free fatty acids, the major fuel used by β-cells during fasting. We show that the mitochondrial permeability transition pore regulator cyclophilin D (CypD) promotes NGSIS, but not glucose-stimulated insulin secretion, by increasing mitochondrial proton leak. Islets from prediabetic obese mice show significantly higher CypD-dependent proton leak and NGSIS compared with lean mice. Proton leak–mediated NGSIS is conserved in human islets and is stimulated by exposure to nonesterified free fatty acids at concentrations observed in obese subjects. Mechanistically, proton leak activates islet NGSIS independently of mitochondrial ATP synthesis but ultimately requires closure of the K_ATP channel. In summary, we have described a novel nonesterified free fatty acid–stimulated pathway that selectively drives pancreatic islet NGSIS, which may be therapeutically exploited as an alternative way to halt fasting hyperinsulinemia and the progression of type 2 diabetes.

The BMP2/4 antagonist and novel adipokine Gremlin 1 is highly expressed in human adipose cells and increased in hypertrophic obesity. As a secreted antagonist, it inhibits the effect of BMP2/4 on adipose precursor cell commitment/differentiation. We examined mRNA levels of Gremlin 1 in key target tissues for insulin and also measured tissue and serum levels in several carefully phenotyped human cohorts. Gremlin 1 expression was high in adipose tissue, higher in visceral than in subcutaneous tissue, increased in obesity, and further increased in type 2 diabetes (T2D). A similar high expression was seen in liver biopsies, but expression was considerably lower in skeletal muscles. Serum levels were increased in obesity but most prominently in T2D. Transcriptional activation in both adipose tissue and liver as well as serum levels were strongly associated with markers of insulin resistance in vivo (euglycemic clamps and HOMA of insulin resistance), and the presence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). We also found Gremlin 1 to antagonize insulin signaling and action in human primary adipocytes, skeletal muscle, and liver cells. Thus, Gremlin 1 is a novel secreted insulin antagonist and biomarker as well as a potential therapeutic target in obesity and its complications T2D and NAFLD/NASH.

Obesity-associated type 2 diabetes mellitus (T2DM) entails insulin resistance and loss of β-cell mass. Adipose tissue mitochondrial dysfunction is emerging as a key component in the etiology of T2DM. Identifying approaches to preserve mitochondrial function, adipose tissue integrity, and β-cell mass during obesity is a major challenge. Mitochondrial ferritin (FtMT) is a mitochondrial matrix protein that chelates iron. We sought to determine whether perturbation of adipocyte mitochondria influences energy metabolism during obesity. We used an adipocyte-specific doxycycline-inducible mouse model of FtMT overexpression (FtMT-Adip mice). During a dietary challenge, FtMT-Adip mice are leaner but exhibit glucose intolerance, low adiponectin levels, increased reactive oxygen species damage, and elevated GDF15 and FGF21 levels, indicating metabolically dysfunctional fat. Paradoxically, despite harboring highly dysfunctional fat, transgenic mice display massive β-cell hyperplasia, reflecting a beneficial mitochondria-induced fat-to-pancreas interorgan signaling axis. This identifies the unique and critical impact that adipocyte mitochondrial dysfunction has on increasing β-cell mass during obesity-related insulin resistance.

Schwann cell–derived exosomes communicate with dorsal root ganglia (DRG) neurons. The current study investigated the therapeutic effect of exosomes derived from healthy Schwann cells (SC-Exos) on diabetic peripheral neuropathy (DPN). We found that intravenous administration of SC-Exos to type 2 diabetic db/db mice with peripheral neuropathy remarkably ameliorated DPN by improving sciatic nerve conduction velocity and increasing thermal and mechanical sensitivity. These functional improvements were associated with the augmentation of epidermal nerve fibers and remyelination of sciatic nerves. Quantitative RT-PCR and Western blot analysis of sciatic nerve tissues showed that SC-Exo treatment reversed diabetes-reduced mature form of miRNA (miR)-21, -27a, and -146a and diabetes-increased semaphorin 6A (SEMA6A); Ras homolog gene family, member A (RhoA); phosphatase and tensin homolog (PTEN); and nuclear factor-B (NF-B). In vitro data showed that SC-Exos promoted neurite outgrowth of diabetic DRG neurons and migration of Schwann cells challenged by high glucose. Collectively, these novel data provide evidence that SC-Exos have a therapeutic effect on DPN in mice and suggest that SC-Exo modulation of miRs contributes to this therapy.

Diabetic retinopathy is the most common microvascular complication of diabetes, and in the advanced diabetic retinopathy appear vitreal fibrovascular membranes that consist of a variety of cells, including vascular endothelial cells (ECs). New therapeutic approaches for this diabetic complication are urgently needed. Here, we report that in cultured human retinal microvascular ECs, high glucose induced expression of p110, which was also expressed in ECs of fibrovascular membranes from patients with diabetes. This catalytic subunit of a receptor-regulated PI3K isoform is known to be highly enriched in leukocytes. Using genetic and pharmacological approaches, we show that p110 activity in cultured ECs controls Akt activation, cell proliferation, migration, and tube formation induced by vascular endothelial growth factor, basic fibroblast growth factor, and epidermal growth factor. Using a mouse model of oxygen-induced retinopathy, p110 inactivation was found to attenuate pathological retinal angiogenesis. p110 inhibitors have been approved for use in human B-cell malignancies. Our data suggest that antagonizing p110 constitutes a previously unappreciated therapeutic opportunity for diabetic retinopathy.

Insulin-induced hypoglycemia leads to far-ranging negative consequences in patients with diabetes. Components of the counterregulatory response (CRR) system that help minimize and reverse hypoglycemia and coordination between those components are well studied but not yet fully characterized. Here, we tested the hypothesis that acyl-ghrelin, a hormone that defends against hypoglycemia in a preclinical starvation model, is permissive for the normal CRR to insulin-induced hypoglycemia. Ghrelin knockout (KO) mice and wild-type (WT) littermates underwent an insulin bolus-induced hypoglycemia test and a low-dose hyperinsulinemic-hypoglycemic clamp procedure. Clamps also were performed in ghrelin-KO mice and C57BL/6N mice administered the growth hormone secretagogue receptor agonist HM01 or vehicle. Results show that hypoglycemia, as induced by an insulin bolus, was more pronounced and prolonged in ghrelin-KO mice, supporting previous studies suggesting increased insulin sensitivity upon ghrelin deletion. Furthermore, during hyperinsulinemic-hypoglycemic clamps, ghrelin-KO mice required a 10-fold higher glucose infusion rate (GIR) and exhibited less robust corticosterone and growth hormone responses. Conversely, HM01 administration, which reduced the GIR required by ghrelin-KO mice during the clamps, increased plasma corticosterone and growth hormone. Thus, our data suggest that endogenously produced acyl-ghrelin not only influences insulin sensitivity but also is permissive for the normal CRR to insulin-induced hypoglycemia.

Diabetes triggers peripheral nerve alterations at a structural and functional level, collectively referred to as diabetic peripheral neuropathy (DPN). This work highlights the role of the liver X receptor (LXR) signaling pathway and the cross talk with the reactive oxygen species (ROS)–producing enzyme NADPH oxidase-4 (Nox4) in the pathogenesis of DPN. Using type 1 diabetic (T1DM) mouse models together with cultured Schwann cells (SCs) and skin biopsies from patients with type 2 diabetes (T2DM), we revealed the implication of LXR and Nox4 in the pathophysiology of DPN. T1DM animals exhibit neurophysiological defects and sensorimotor abnormalities paralleled by defective peripheral myelin gene expression. These alterations were concomitant with a significant reduction in LXR expression and increase in Nox4 expression and activity in SCs and peripheral nerves, which were further verified in skin biopsies of patients with T2DM. Moreover, targeted activation of LXR or specific inhibition of Nox4 in vivo and in vitro to attenuate diabetes-induced ROS production in SCs and peripheral nerves reverses functional alteration of the peripheral nerves and restores the homeostatic profiles of MPZ and PMP22. Taken together, our findings are the first to identify novel, key mediators in the pathogenesis of DPN and suggest that targeting LXR/Nox4 axis is a promising therapeutic approach.

Central to the development of diabetic macro- and microvascular disease is endothelial dysfunction, which appears well before any clinical sign but, importantly, is potentially reversible. We previously demonstrated that hyperglycemia activates nuclear factor of activated T cells (NFAT) in conduit and medium-sized resistance arteries and that NFAT blockade abolishes diabetes-driven aggravation of atherosclerosis. In this study, we test whether NFAT plays a role in the development of endothelial dysfunction in diabetes. NFAT-dependent transcriptional activity was elevated in skin microvessels of diabetic Akita (Ins2^+/–) mice when compared with nondiabetic littermates. Treatment of diabetic mice with the NFAT blocker A-285222 reduced NFATc3 nuclear accumulation and NFAT-luciferase transcriptional activity in skin microvessels, resulting in improved microvascular function, as assessed by laser Doppler imaging and iontophoresis of acetylcholine and localized heating. This improvement was abolished by pretreatment with the nitric oxide (NO) synthase inhibitor l-N^G-nitro-l-arginine methyl ester, while iontophoresis of the NO donor sodium nitroprusside eliminated the observed differences. A-285222 treatment enhanced dermis endothelial NO synthase expression and plasma NO levels of diabetic mice. It also prevented induction of inflammatory cytokines interleukin-6 and osteopontin, lowered plasma endothelin-1 and blood pressure, and improved mouse survival without affecting blood glucose. In vivo inhibition of NFAT may represent a novel therapeutic modality to preserve endothelial function in diabetes.

Diabetic retinopathy (DR) is a widespread vision-threatening disease, and neuroretinal abnormality should be considered as an important problem. Brain-derived neurotrophic factor (BDNF) has recently been considered as a possible treatment to prevent DR-induced neuroretinal damage, but how BDNF is upregulated in DR remains unclear. We found an increase in hydrogen peroxide (H₂O₂) in the vitreous of patients with DR. We confirmed that human retinal endothelial cells secreted H₂O₂ by high glucose, and H₂O₂ reduced cell viability of MIO-M1, Müller glia cell line, PC12D, and the neuronal cell line and lowered BDNF expression in MIO-M1, whereas BDNF administration recovered PC12D cell viability. Streptozocin-induced diabetic rats showed reduced BDNF, which is mainly expressed in the Müller glia cell. Oral intake of eicosapentaenoic acid ethyl ester (EPA-E) ameliorated BDNF reduction and oscillatory potentials (OPs) in electroretinography (ERG) in DR. Mass spectrometry revealed an increase in several EPA metabolites in the eyes of EPA-E–fed rats. In particular, an EPA metabolite, 18-hydroxyeicosapentaenoic acid (18-HEPE), induced BDNF upregulation in Müller glia cells and recovery of OPs in ERG. Our results indicated diabetes-induced oxidative stress attenuates neuroretinal function, but oral EPA-E intake prevents retinal neurodegeneration via BDNF in Müller glia cells by increasing 18-HEPE in the early stages of DR.