Roger H Unger
Aug 1, 1995; 44:863-870
Perspectives in Diabetes

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

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

JW Baynes
Jan 1, 1999; 48:1-9
Articles

Norikazu Maeda
Sep 1, 2001; 50:2094-2099
Pathophysiology

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

Patrice D. Cani
Jun 1, 2008; 57:1470-1481
Metabolism

Patrice D. Cani
Jul 1, 2007; 56:1761-1772
Obesity Studies

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...

Many taxi and bus operators in sections of Kingston and St Andrew are seemingly adhering to social-distancing guidelines outlined by the Government for the sector, in terms of the number of passengers they are allowed to transport at a time. These...

ROSEAU, Dominica, CMC –A senior education official Thursday said students would sit the Grade Six National Assessment examinations later this year, despite the disruption caused to the education system by the coronavirus (COVID-19). Dominica...

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

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.

Major League Baseball Commissioner Rob Manfred has never been to an Opening Day in Cincinnati. Manfred is excited to experience one for himself, now that he has the honor of being the grand marshal of the 100th Findlay Market Opening Day Parade on March 28.

THE EDITOR, Madam: On Wednesday at 8:30 a.m., while watching TVJ, I saw Get Moving home workout series. Very good, TVJ and the Ministry of Health, for bringing this workout programme into our homes. Minister Tufton was a participant; he truly...

Incretin hormone dysregulation contributes to reduced insulin secretion and hyperglycemia in patients with type 2 diabetes mellitus (T2DM). Resistance to glucose-dependent insulinotropic polypeptide (GIP) action may occur through desensitization or downregulation of β-cell GIP receptors (GIP-R). Studies in rodents and cell lines show GIP-R expression can be regulated through peroxisome proliferator–activated receptor (PPAR) response elements (PPREs). Whether this occurs in humans is unknown. To test this, we conducted a randomized, double-blind, placebo-controlled trial of pioglitazone therapy on GIP-mediated insulin secretion and adipocyte GIP-R expression in subjects with well-controlled T2DM. Insulin sensitivity improved, but the insulinotropic effect of infused GIP was unchanged following 12 weeks of pioglitazone treatment. In parallel, we observed increased GIP-R mRNA expression in subcutaneous abdominal adipocytes from subjects treated with pioglitazone. Treatment of cultured human adipocytes with troglitazone increased PPAR binding to GIP-R PPREs. These results show PPAR agonists regulate GIP-R expression through PPREs in human adipocytes, but suggest this mechanism is not important for regulation of the insulinotropic effect of GIP in subjects with T2DM. Because GIP has antilipolytic and lipogenic effects in adipocytes, the increased GIP-R expression may mediate accretion of fat in patients with T2DM treated with PPAR agonists.

Insulin-mediated microvascular recruitment (IMVR) regulates delivery of insulin and glucose to insulin-sensitive tissues. We have previously proposed that perivascular adipose tissue (PVAT) controls vascular function through outside-to-inside communication and through vessel-to-vessel, or "vasocrine," signaling. However, direct experimental evidence supporting a role of local PVAT in regulating IMVR and insulin sensitivity in vivo is lacking. Here, we studied muscles with and without PVAT in mice using combined contrast-enhanced ultrasonography and intravital microscopy to measure IMVR and gracilis artery diameter at baseline and during the hyperinsulinemic-euglycemic clamp. We show, using microsurgical removal of PVAT from the muscle microcirculation, that local PVAT depots regulate insulin-stimulated muscle perfusion and glucose uptake in vivo. We discovered direct microvascular connections between PVAT and the distal muscle microcirculation, or adipomuscular arterioles, the removal of which abolished IMVR. Local removal of intramuscular PVAT altered protein clusters in the connected muscle, including upregulation of a cluster featuring Hsp90ab1 and Hsp70 and downregulation of a cluster of mitochondrial protein components of complexes III, IV, and V. These data highlight the importance of PVAT in vascular and metabolic physiology and are likely relevant for obesity and diabetes.

Excessive fructose consumption is closely linked to the pathogenesis of metabolic disease. Carbohydrate response element-binding protein (ChREBP) is a transcription factor essential for fructose tolerance in mice. However, the functional significance of liver ChREBP in fructose metabolism remains unclear. Here, we show that liver ChREBP protects mice against fructose-induced hepatotoxicity by regulating liver glycogen metabolism and ATP homeostasis. Liver-specific ablation of ChREBP did not compromise fructose tolerance, but rather caused severe transaminitis and hepatomegaly with massive glycogen overload in mice fed a high-fructose diet, while no obvious inflammation, cell death, or fibrosis was detected in the liver. In addition, liver ATP contents were significantly decreased by ChREBP deficiency in the fed state, which was rendered more pronounced by fructose feeding. Mechanistically, liver contents of glucose-6-phosphate (G6P), an allosteric activator of glycogen synthase, were markedly increased in the absence of liver ChREBP, while fasting-induced glycogen breakdown was not compromised. Furthermore, hepatic overexpression of LPK, a ChREBP target gene in glycolysis, could effectively rescue glycogen overload and ATP reduction, as well as mitigate fructose-induced hepatotoxicity in ChREBP-deficient mice. Taken together, our findings establish a critical role of liver ChREBP in coping with hepatic fructose stress and protecting from hepatotoxicity by regulating LPK.

A single bout of exercise enhances insulin action in the exercised muscle. However, not all human studies find that this translates into increased whole-body insulin action, suggesting that insulin action in rested muscle or other organs may be decreased by exercise. To investigate this, eight healthy men underwent a euglycemic-hyperinsulinemic clamp on 2 separate days: one day with prior one-legged knee-extensor exercise to local exhaustion (~2.5 h) and another day without exercise. Whole-body glucose disposal was ~18% lower on the exercise day as compared with the resting day due to decreased (~37%) insulin-stimulated glucose uptake in the nonexercised muscle. Insulin signaling at the level of Akt2 was impaired in the nonexercised muscle on the exercise day, suggesting that decreased insulin action in nonexercised muscle may reduce GLUT4 translocation in response to insulin. Thus, the effect of a single bout of exercise on whole-body insulin action depends on the balance between local effects increasing and systemic effects decreasing insulin action. Physiologically, this mechanism may serve to direct glucose into the muscles in need of glycogen replenishment. For insulin-treated patients, this complex relationship may explain the difficulties in predicting the adequate insulin dose for maintaining glucose homeostasis following physical activity.

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.

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.

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.

Invitation Only Research Event

Event participants

Paula Hodges QC, Partner; Head, Global Arbitration Practice, Herbert Smith Freehills
Stéphane Brabant, Partner; Chairman, Africa Practice Group, Herbert Smith Freehills

Research Event

Event participants

Tom Butler, Chief Executive Officer, International Council for Mining and Metals (ICMM)
Evelyn Dietsche, Associate Fellow, Energy, Environment and Resources, Chatham House
Chair: Bernice Lee, Executive Director, Hoffman Centre, Chatham House 

Invitation Only Research Event

The Arizona Diamondbacks agreed to terms on a contract extension with manager Torey Lovullo on Tuesday.

Hi Steve, wondering if this is a rebuild year?

With Greg Holland now signed, will he be the closer or is that still going to be Archie Bradley? Beat reporter Steve Gilbert answers this question and more from fans as Spring Training approaches.

As D-backs pitchers and catchers begin their first official workout of the spring on Wednesday morning, one of the biggest questions facing the organization is who will fill the leadership vacuum.

Monday morning, D-backs manager Torey Lovullo will stand in front of his entire team prior to the first full-squad workout of the spring.

Agencies have criticised the lack of action to protect the health needs of sex workers during the pandemic, with the English Collective of Prostitutes (ECP) warning of a “ticking time bomb of health...

Neuroinflammation is important in amyotrophic lateral sclerosis (ALS). The P2X7 receptor (P2X7R) is a promising target for neuroinflammation. The objective of this study was to compare ¹⁸F-DPA714, a second-generation translocator protein tracer, with ¹¹C-JNJ717, a novel P2X7R tracer, in vitro and in vivo in ALS. Methods: For the in vitro portion of the study, autoradiography with ¹⁸F-DPA714 and ¹¹C-JNJ717 was performed on human ALS brain sections in comparison to immunofluorescence with Iba1 and GFAP. For the in vivo portion, 3 male patients with early-stage ALS (59.3 ± 7.2 y old) and 6 healthy volunteers (48.2 ± 16.5 y old, 2 men and 4 women) underwent dynamic PET/MR scanning with ¹⁸F-DPA714 and ¹¹C-JNJ717. Volume-of-distribution images were calculated using Logan plots and analyzed on a volume-of-interest basis. Results: Autoradiography showed no difference in ¹¹C-JNJ717 binding but did show increased ¹⁸F-DPA714 binding in the motor cortex correlating with Iba1 expression (glial cells). Similar findings were observed in vivo, with a 13% increase in ¹⁸F-DPA714 binding in the motor cortex. Conclusion: In symptomatic ALS patients, ¹⁸F-DPA714 showed increased signal whereas ¹¹C-JNJ717 was not elevated.

Fibroblast activation protein (FAP), which promotes tumor growth and progression, is overexpressed in cancer-associated fibroblasts of many human epithelial cancers. Because of its low expression in normal organs, FAP is an excellent target for theranostics. In this study, we used radionuclides with relatively long half-lives, ⁶⁴Cu (half-life, 12.7 h) and ²²⁵Ac (half-life, 10 d), to label FAP inhibitors (FAPIs) in mice with human pancreatic cancer xenografts. Methods: Male nude mice (body weight, 22.5 ± 1.2 g) were subcutaneously injected with human pancreatic cancer cells (PANC-1, n = 12; MIA PaCa-2, n = 8). Tumor xenograft mice were investigated after the intravenous injection of ⁶⁴Cu-FAPI-04 (7.21 ± 0.46 MBq) by dynamic and delayed PET scans (2.5 h after injection). Static scans 1 h after the injection of ⁶⁸Ga-FAPI-04 (3.6 ± 1.4 MBq) were also acquired for comparisons using the same cohort of mice (n = 8). Immunohistochemical staining was performed to confirm FAP expression in tumor xenografts using an FAP-α-antibody. For radioligand therapy, ²²⁵Ac-FAPI-04 (34 kBq) was injected into PANC-1 xenograft mice (n = 6). Tumor size was monitored and compared with that of control mice (n = 6). Results: Dynamic imaging of ⁶⁴Cu-FAPI-04 showed rapid clearance through the kidneys and slow washout from tumors. Delayed PET imaging of ⁶⁴Cu-FAPI-04 showed mild uptake in tumors and relatively high uptake in the liver and intestine. Accumulation levels in the tumor or normal organs were significantly higher for ⁶⁴Cu-FAPI-04 than for ⁶⁸Ga-FAPI-04, except in the heart, and excretion in the urine was higher for ⁶⁸Ga-FAPI-04 than for ⁶⁴Cu-FAPI-04. Immunohistochemical staining revealed abundant FAP expression in the stroma of xenografts. ²²⁵Ac-FAPI-04 injection showed significant tumor growth suppression in the PANC-1 xenograft mice, compared with the control mice, without a significant change in body weight. Conclusion: This proof-of-concept study showed that ⁶⁴Cu-FAPI-04 and ²²⁵Ac-FAPI-04 could be used in theranostics for the treatment of FAP-expressing pancreatic cancer. α-therapy targeting FAP in the cancer stroma is effective and will contribute to the development of a new treatment strategy.

In glioma patients, differentiation between tumor progression (TP) and treatment-related changes (TRCs) remains challenging. Difficulties in classifying imaging alterations may result in a delay or an unnecessary discontinuation of treatment. PET using O-(2-¹⁸F-fluoroethyl)-l-tyrosine (¹⁸F-FET) has been shown to be a useful tool for detecting TP and TRCs. Methods: We retrospectively evaluated 127 consecutive patients with World Health Organization grade II–IV glioma who underwent ¹⁸F-FET PET imaging to distinguish between TP and TRCs. ¹⁸F-FET PET findings were verified by neuropathology (40 patients) or clinicoradiologic follow-up (87 patients). Maximum tumor-to-brain ratios (TBR_max) of ¹⁸F-FET uptake and the slope of the time–activity curves (20–50 min after injection) were determined. The diagnostic accuracy of ¹⁸F-FET PET parameters was evaluated by receiver-operating-characteristic analysis and ² testing. The prognostic value of ¹⁸F-FET PET was estimated using the Kaplan–Meier method. Results: TP was diagnosed in 94 patients (74%) and TRCs in 33 (26%). For differentiating TP from TRCs, receiver-operating-characteristic analysis yielded an optimal ¹⁸F-FET TBR_max cutoff of 1.95 (sensitivity, 70%; specificity, 71%; accuracy, 70%; area under the curve, 0.75 ± 0.05). The highest accuracy was achieved by a combination of TBR_max and slope (sensitivity, 86%; specificity, 67%; accuracy, 81%). However, accuracy was poorer when tumors harbored isocitrate dehydrogenase (IDH) mutations (91% in IDH-wild-type tumors, 67% in IDH-mutant tumors, P < 0.001). ¹⁸F-FET PET results correlated with overall survival (P < 0.001). Conclusion: In our neurooncology department, the diagnostic performance of ¹⁸F-FET PET was convincing but slightly inferior to that of previous reports.

The Jamaica Stock Exchange (JSE) Combined Index regained lost ground on Tuesday with an advance/decline ratio of 28/38 The JSE index advanced marginally 1,154.11 points or 0.32 per cent to close at 360,497.91. The JSE Main Market Index was up...

The Jamaica Stock Exchange (JSE) Combined Index continued its mild rally on Wednesday with an advance/decline ratio of 34/29 The JSE index advanced marginally 1,983.51points or 0.55 per cent to close at 362,481.42. The JSE Main Market Index was up...

FOUR MORE applicants are vying to provide mobile payment services in various formats, including one applicant seeking to use phone credit as a cash equivalent, but successful applicants will fall under a new framework the regulator calls its “...

WITH THE productive sector experiencing a shortage of foreign exchange for the past two months, the Jamaican Manufacturers and Exporters Association, JMEA, says it has appealed to the Bank of Jamaica, BOJ, for direct access to US currency for three...

Invitation Only Research Event

Event participants

Alistair Burt, Conservative Member of Parliament (1983-97 and 2001-19); Minister of State for the Middle East, UK Foreign & Commonwealth Office and Minister of State at the Department for UK International Development (2017-19)

Members Event

Event participants

Helen Thompson, Professor of Political Economy, University of Cambridge; Host, Talking Politics
Chairs: Hans Kundnani, Senior Research Fellow, Europe Programme, Chatham House
Laura Cram, Professor of European Politics, University of Edinburgh. Co-Editor, Government and Opposition: An International Journal of Comparative Politics
 

Members Event

Event participants

Anu Bradford, Author, The Brussels Effect: How the European Union Rules the World; Henry L. Moses Professor of Law and International Organization, Columbia Law School

Creon Butler, Research Director, Trade, Investment & New Governance Models; Director, Global Economy and Finance Programme, Chatham House

Chair: Pepijn Bergsen, Research Fellow, Europe Programme, Chatham House

Research Event

Event participants

Gavin Barwell, Downing Street Chief of Staff to Prime Minister Theresa May (2017-19)
Chair: Thomas Raines, Director, Europe Programme, Chatham House

Invitation Only Research Event

Event participants

Tim Yeo, Chairman, The New Nuclear Watch Institute
Chair: Antony Froggatt, Senior Research Fellow, Energy, Environment and Resources, Chatham House 

Invitation Only Research Event